PMC用户指南

PubMed Central®（PMC）is a free full-text archive of biomedical and life sciences journal literature at the U.S.National Institutes of Health's National Library of Medicine（NIH/NLM）。This guide is meant to help you use PMC to find and read articles of interest to you.Answers to many common questions about PMC are available in thePMC常见问题解答。

标题：If you are a researcher seeking to submit an author manuscript to PMC，visit theNIHMS.（For more information on submissions to PMC，seeFor Authors.）

PMC Journal List

Visit thePMC Journal Listto browse a list of journals added to PMC in the last60 days can be found by clicking on the last60新建tab。

You can also discover PMC’s unique historical collections，open access and text mining collections，funder collections，and more on thePMC Collectionspage。

Coming Soon:Updated PMC Journal List

In March 2024，NCBI announced the availability of a public preview of upcoming updates to the PMC website单击功能区上，including updated functionality and labeling of the PMC journal list and changes to some of the fields in the PMC journals data provided in downloadable format.Preview the updated journal list at:https://pmc.ncbi.nlm.nih.gov/journals/

1. To search for a journal or set of journals enter your search terms into the“Search for Journals”search box。The search only looks for words in a journal's title。
2. Auto-complete options are presented to help you find specific journals。
3. You may clear your search results with the“Reset to Full Journal List”link。
4. Narrow your search results using the filters on the right-hand side of the page.See theJournal List Field descriptionsfor details about the specific fields。
5. On a mobile device，filters are available by clicking on the icon in the upper right corner of your display。
6. Download the full journal list in comma separated value format（csv）using the“Download full journal list”link。
7. Download the results of your search and／or filtering in csv format with the“Download results”link。
8. Didn't find what you were looking for？Theupdated PMC journal list only includes journals withan agreement with NLMto make the final published version of all their articles，or all their NIH-funded articles available in PMC；or are historically-significant journals from theBiomedical Journal Digitization project。PMC also includes individual articles from other journals，either deposited as manuscripts by the authors in support of a funder mandate，orby the publisher through aSelective Deposit arrangement打开；These journals are not searchable in the updated PMC journal list.Try a separate search of theNLM Catalog:Journals referenced in the NCBI Databases用户指南section on从articles from a specific journal。
9. For each journal that matches your search terms and filter options，arecord with basic bibliographic data and information about PMC coverage is displayed。
10. Use the“See all articles in PMC from this journal”link in each record to run a search to retrieve all articles for the journal in PMC。

日记列表字段描述

For each journal record，the following data fields are displayed:

PMC Article Search

To search for full-text articles in PMC，type the term or concept you are looking for into the search box at the top of any PMC page and click the search button or hit enter.Suggestions will display as you type your search terms.This feature is baseed on PubMed query log analysis described in“PubMed为Finding Query Suggestions“

For many searches，it is not necessary to use special tags or syntax，though PMC does support more预成形和成形机to refine your results and help you find the information you are seeking.ThePMC单回路计数器tool is also available to find PMC articles by specific citation information。

标题：Searches are not case sensitive。

Learn to search by：

Author｜Journal｜碰撞，碰撞｜Funder｜许可证，许可证｜发布日期｜PMC Live Date｜Article Property

Other search topics:

Phrase Searching｜中继搜索终端｜“与，或，不”

By Author

In the Search box，enter the author's full name or their last name followed by initials，without punctuation.If you only know the author's last name，use theauthor search field tagas shown in an example below。

Author names are automatically truncated to account for varying initials and designations such as Jr.To turn off the truncation，use double quotes around the author's name with the author search field tag[au]as shown in an example below。

Author Searches	搜索Query Examples
完全名称	Joshua Lederberg joshua lederberg
Last Name and Given Name Initials	Lipman DJ lipman dj
Last Name（with author search field tag[au]）	lipman[au]
最后名称和Given Name Initials（with truncation turned off byusing quotes）	“smith j”[au]

按日记账

In the Search box，enter the journal title，the NLM journal title abbreviation，or theISSN单击功能区上，the8-digit standardized international code used to identify journals。

日记搜索	搜索Query Examples
全封闭式title	日记账资产负债表 车辆用配电装置
全封闭式导槽	“日记库关联”[ta] “日记库关联”[journal of the Medical Library Association“[journal]
Journal title abbreviation	Proc Natl Acad Sci U S A
Journal title abbreviation with journal title abbreviation search field	“Proc Natl Acad Sci U S A”[ta] “Proc Natl Acad Sci U S A”[journal]
ISSN	1948-7193 1948-7193[ta] 1948-7193[journal]

按，按

collections in PMC by entering the appropriate preset PMC search filter（s）：

碰撞，碰撞	搜索队列
Author Manuscripts	“author manuscript”[filter]
NIH Preprints	preprint filter
PMC COVID-19 Collection	“pmc phe collection”[filter]
开放访问子集	“open access”[filter]
Digitized Historical Biomedical Journals	“is scanned”[filter] “historical OCR”[filter]

See，SeePMC Collectionsfor additional information。

By Funder

用户append the preset search filters shown in the Search Query column below to find articles supported by funding organizations that have formally partnered with NLM to use PMC as a repository for their funded research。

Research Funder	搜索队列
National Institutes of Health（NIH）	“nih funded”[filter]
管理公共许可证	“acl funded”[filter]
Agency for Healthcare Research and Quality（AHRQ）	“ahrq funded”[filter]
磁盘控制和准备中心	“cdc funded”[filter]
Food and Drug Administration（FDA）	“fda funded”[filter]
专用安全性和响应	“aspr funded”[filter]
环境保护协议	“epa funded”[filter]
National Aeronautics and Space Administration（NASA）	“nasa funded”[filter]
National Institute of Standards and Technology（NIST）	“nist funded”[filter]
Homeland Security（DHS）	“dhs funded”[filter]
安全措施	“va funded”[filter]

See，SeePMC和Research Funder Policiesfor additional information。

按许可证

限制your search results to articles in thePMC Open Access Subsetwith specific Creative Commons（CC）licenses by appending the preset search filters shown in the Search Query column below。For descriptions of these licenses，please see the Creative Commons site，About the Licenses.Please note that not all articles in the Open Access Subset have a CC license。

许可证类型	搜索队列
Any CC license	“cc license”[filter]
CC BY（Attribution）	“ccby license”[filter]
CC BY-ND（Attribution，no derivatives）	“ccby-nd license”[filter]
CC BY-NC（Attribution，noncommercial）	“ccby-nc license”[filter]
CC BY-NC-ND（Attribution，noncommercial，no derivatives）	“ccby-nc-nd license”[filter]
CC BY-NC-SA（Attribution，noncommercial，share-alike）	“ccby-nc-sa license”[filter]
CC BY-SA（Attribution，share-alike）	“ccby-sa license”[filter]
CC0	“cc0许可证”[filter]

These filters are based on license information，which is provided to PMC by publishers and other content providers.Please note that，in some cases，there are discrepancies between these machine-readable identifiers and the actual text of the license statements.In2013，PMC instituted new rules to help suenre of the列车运行情况单击功能区上，which apply to all content received since then。

按发布日期

Enter dates into the Search box using the format YYYYY/MM/DD[pubdate]，orenter a date range using a colon（：）between each date followed bya date search field tag。

By PMC Live Date

Enter dates into the Search box using the format YYYYY/MM/DD[pmclivedate]，orenter a date range using a colon（：）between each date followed bya date search field tag。

If you are looking for the PMC Live Date for a specific record，

• See the corresponding PubMed record for the PMC release date of embargoed articles。
• See the“available in PMC”date included in the citation on the PMC record。
• See Version 2.0 of eSummary to get the PMC Live Date for any article in the database e.g。，https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esummary.fcgi？db=pmc&version=2.0&id=14900。

Deposit date data are not available。

By Article Property

搜索器append a search with any of the following queries to find articles with these specific properties in PMC:

Article property	搜索队列
Has supplementary material	“has supddata”[filter]
Has a“数据可用性”和/或a“数据可访问性”section	“has data avail”[filter]
Has references tagged with a proper type to be rendered as data citations	“has data citations”“filter”
专用过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境过境	“has associated data”[filter]
Has abstract	“has abstract”[filter]
Has PDF	“has pdf”[filter]
Hasa preprint version also available in PMC	“has preprint”[filter]
Has video	“has video”[filter]
Is a scanned article	“is scanned”[filter]
Is a letter	letter[filter]
Is a reply to a letter	reply[filter]
管道外压环	“外部压力”[filter]
Is an articles that has a published expression of concern	“has expression of concern”[filter]
Is a correction to an article	correction filter
Is an article that has a published correction	“is corrected”[filter]
不规则反射	反射式过滤器
绝缘绝缘板，绝缘板，绝缘板	“is retracted”[filter]
Is cited by other articles in PMC	“cited in pmc”[filter]
I in PMC and under embargo	“pmc embargo”[filter]

Phrase Searching

PMC does not perform adjacency searching.However，many phrases are recognized by theSH翻译表在，在，在自动定时映射feature.For example，if you enter“influenza in birds”，PMC recognizes this phrase asa MeSH concept.If a phrase is not recognized，you can instruct PMC to bypass automatic term mapping and search for a specific phrase using the following formats:

• Enclose the phrase in double quotes：“kidney allograft”.When you enter your search terms as a phrase（using quotation marks），PMC will not perform automatic term mapping，which includes expansion ofSH terms。
• 使用，使用定位销：kidney allograft[tw]
• 使用空间：“first-line”

Phrases may appear in a PMC article but not be in the phrases index.To browse indexed phrases，use the显示索引featureincluded in the Advanced Search Builder:select a search field，enter the beginning of a phrase，and then click Show Index。

中继搜索终端

To search for all terms that begin with a word，enter the word followed by an asterisk（*）。For example，flavor*finds terms that begin with the root term flavor，such as flavored，flavorful，flavoring，etc。

PMC searches for the first600variations of a truncated term.If a truncated term（e.g.，“tox*”）produces more than600variations，PMC displays a warning message to lengthen the root word to search for all endings。

车辆关闭自动定时映射and the automatic expansion of aSH term。

Truncating a word in a multi-word query may result in an unexpected phrase search.For example，the search fetus infection*maternal will treat fetus infection*as a phrase。

Truncation stops at the end of a term，that is，it does not process beyond a space。

“与，或，不”

企业Boolean operator in uppercase characters to combine or exclude search terms：

• AND retrieves results that include all of the search terms。
• OR retrieves results that include at least one of the search terms。
• NOT excludes the retrieval of terms from your search。

Use parentheses to group terms as desired。

查看搜索结果

PMC search results are displayed by default in order of relevance with20results per page.The default sort order for search results is based on an algorithm thatalyzes the full text of every PMC article that contains any of your search terms.For a given search query，“weight”is calculated for each article depending on how many search terms are found，which fields they are found in，and the size of the article.Although recently-published articles are given more weight，this is is not a major sorting factor。

Learn to：

搜索结果页｜自定义用户搜索结果显示｜查看和编辑搜索详细资料｜保存和故障搜索结果和故障

搜索结果页

From the search results page you can

1. Click on the record title to access an article
2. 双导流板进气口，双导流板进气口进气口进气口HTML Article View或PDF-More about formats can be found atViewan Article）。
3. Limit results by article attribute，publication date，or funder using the sidebar filters.Additional filter help can be found here:防滑性能单击功能区上，发布日期单击功能区上，funder单击功能区上，许可证，许可证单击功能区上，collection。
4. Expand your results to include articles currently under embargo in PMC alongside the publicly accessible results，by selecting the入口式电炉sidebar filter。
5. Find related data in other NCBI datasets。
6. Send your results to a file，email them，or save them using the Clipboard and Collections tools。
7. Add custom filters。

Each action above is high lighted in the screenshot below with the corresponding number。

自定义用户搜索结果显示

PMC search results initially display in a summary format with20results per page sorted by relevance。

使用，使用显示设置对：

• 变更，变更，变更
• 变更，变更，变更
• your search results

用户电话号码簿显示设置pull-down menu to select a different sort by setting:

• 默认定位器
• 发布日期
• Journal
• PMC Live Date

查看和编辑搜索详细资料

The PMC search program may modify your search terms to enhance your retrieval.Sometimes these changes may not match what you have in mind.For example，if you search for cystic fibrosis by its abbreviation cf，thecf searchretrieves some articles that do not discuss cystic fibrosis.To see why PMC retrieved these articles，review the搜索详细信息box to see how PMC translated cf to search forarticles about cerebrospinal fluid or cf.（For additional information，see自动定时映射and，andsearch rules.）

• 编辑，编辑搜索详细信息box by adding or deleting terms and then click the Search button just below the box。
• Click on“See more…”to see more detailed information about the query used to run the search as shown in the screenshot below。

从搜索详细信息：

• 编辑，编辑快速翻译box by adding or deleting terms and then click the搜索，搜索button。
• Get a URL to bookmark this search for future use by clicking the网址button.Searches created by combiningHistory search numbersshould not be saved using the URL feature，because the search numbers are not persistent。
• Get a list of anyStopwordsthat were ignored.（arow not pictured in the screenshot below labeled Stopword（s）ignored will display if stopwords are found.）
• 查看，查看，查看结果，结果link；click on it to run the search。
• Learn how each term was translated using PMC's search rules and syntax by viewing the翻译，翻译area。
• 查看，查看，查看，查看用户queryarea and see whether there were any syntax errors。

保存和故障结果和故障

PMC offers a wide variety of methods to save search results.Use the Send to dropdown in order to：

• 保存到文件（may take several minutes for a large retrieval）。The default for the Send to File feature is to save the entire retrieval unless you select specific results。
• Send results by e-mail。You may email up to 200items at a time to a single email address.Your PMC results will be sent from the NCBI automatic mail server，sent byEntrez单击功能区上nobody@ncbi.nlm.nih.gov]。Do not reply to this message.This is not a functioning customer service email address。
• Save results to a RSS feed。PMC does not currently support RSS feeds directly through the PMC search page.However，in PubMed you can create an RSS feed by using a search that restrieval to the PMC subset if you include AND pubmed pmc[sb]in the query。Documentation is also available for在泵内加热.Note:Some PMC article types按不允许的泵门and so will not be included in the RSS feed。
• Save results temporarily in your Clipboard。TheClipboardgives you a place to collect selected results from one or several searches.The Clipboard will be lost after8hours of inactivity on PMC or on any of the otherEntrezdatabases。
• 我的NCBI Collections（you must be signed in to My NCBI to use this feature）。There is no limit to the number of collections you may store in My NCBI.In addition，collections can be made public to share with others.（See我的NCBI帮助Collectionsfor more information.）

使用高级搜索

Tools included on the Advanced Search page help users to：search for terms in a specific field，combine searches and build large，complex search strings，and compare the number of results for different queries.A link to the Advanced Search page is available by the search box。

Learn to：搜索特定字段｜Browse the Index of Terms｜查看用户搜索历史记录

搜索特定字段

1. “All Fields”drop-down menu，select the field you would like to search。
2. Add terms from the builder to the query box to construct your search.The default Boolean operator is AND；if desired，choose OR or NOT from the pull-down menu。
3. Once you have finished adding terms to the query box，click Search（or Add to History）to run the search。

You may also search a specific field-andbypass automatic term mapping-by adding a search tag to a term（see:搜索指令和标记）。The search tag must be enclosed in square brackets。

Browse the Index of Terms

The Advanced Search Builder includes the Show Index List feature，which provides an alphabetical display of terms appearing in selected PMC search fields.You can browse by all fields or within specific fields such as MeSH Terms.The显示索引list will only display for fields that are compatible with this feature。

1. Enter a term in the search box，then click显示索引。
2. Scroll until you find a term you want to include in your search，and then high light it to add it to the search box.The index displays an alphabetical list of search terms and the approximate number of citations for each term（the actual citation count is returned when the search is executed）。
3. Add terms from the builder to the query box to construct your search.The builder will automatically OR（and add parentheses）for multiple terms selected from the index。

查看用户搜索历史记录

Your past searches appear on the高级搜索总成数，总成数历史，历史.This feature requires your web browser to accept cookies。

设计column in the History table appear below:

搜索。Searches are numbered in chronological order。搜索numbersmay be used in place of the search string itself when combining queries（e.g.，#1OR#2）。

A repeated query will move to the top of历史，历史but will retain its original numbering。

标题：Click the“Search number”to display additional options，including Boolean operators OR or NOT.Other menu options include:

• 删除，删除
• 显示比例比例
• 显示search details
• 保存，保存我的NCBI

Add to Builder。Adding queries from History places the search string into the Query box to be used in the next search。

Query。This column shows previous search strings you entered。

Items Found。This is the total number of citations retrieved for that query.Click the number to run the search and see the results in PMC。

标题：Use the“Add to history”link in Advanced search to display the items found before displaying the search results。To display the results，click the history“Items found”link。

Time。Timestamp of when the search was conducted。

To generate a CSV file of current History items，click“Download history”.Please note，微软Excel is typically unable to display or print more than a maximum of 1024 characters in a cell；therefore，you may want to open the CSV file with a text editor to display your complete searches。

Click“Clear History”to remove all queries from History；otherwise，History expires after8hours of inactivity。

Viewan Article

This section high lights some of the key functionality available in PMC's article display。

If you want to

1. 在搜索中搜索：The search bar supports search across the articles in the PMC archive.To search other NCBI databases，use the search bar on theNCBI homepageor onPMC search resultspages。

2. View the article in other formats： See the“Other Formats”section at the top of the right-hand column to access the article as a PDF。

3. View the corresponding PubMed record： Click on the PMID link。

4. Get a formatted citation of the article:Click on the blue“Cite”button in the“Actions”section in the right-hand column to getformatted citation information。

5. 保存到我的NCBI collection:Click the blue“Collections”button in the“Actions”section in the right-hand column to add an article to any of your collections in My NCBI.When an article has been added to a collection，the icon in the button turns white.You can also use this button to create a new collection before adding an article to it。

6. 共享：Click on a social media button or the link button in the“Share”section in the right-hand column。

7. View articles similar to the article you are viewing：Click“Similar articles”to open the section and see a list of articles from PubMed that aresimilar to the one you are reading.Click an article title to view the record in PubMed，or click the“See all in PubMed”link to see the full list of similar articles available from PubMed。

8. View articles that cite the article you are viewing：Click“Cited by other articles”to open the section and see a list of articles from PubMed that循环，循环.Click an article title to view the record in PubMed，or click the“See all in PubMed”link to see a full list of articles available from PubMed。

9. 访问链接到已恢复的连接程序NCBI数据库：Click“Links to NCBI Databases”to open the section and see available links to related records in other NCBI databases。Click on the name of the NCBI database to navigate to that resource。

10. Find data related to the article:The Associated Data box will display in articles that include data citations，data availability statements，or supplementary materials。

11. View references within the article: Hover over or click on any linked reference in the article to view the complete reference list entry。

12. 查看your recent activity on the PMC site：You can find details on previous searches from your session by clicking on“高级分类”next to the search bar。You may also visit your 我的NCBI dashboard to view recent activity。

13. 访问similar features on mobile and smaller screens：Click the“three dot”menu in the upper left-hand corner of an article page to see a list of these features on mobile devices and when you use a narrow browser window on a desktop。

You can also click on an author's name to search for other publications by that author in PubMed。

摘要/页面浏览显示器

从我身边反向诊断项目在使用中，PMC2483210）。The full text of these articles is also available in PDF format（as scanned copy of the original print version）。Some of these articles include a选定References section offering links to citation records in PubMed or to other PMC articles。

Cite an Article

The Citation Exporter makes it easy to retrieve either styled citations that you can copy/paste into your manuscripts or download into a format compatible with your bibliographic reference manager software.You can access the citation by

• clicking the“Cite”button an article record

When，clicked，this opens a pop-up window that you canuse to copy and paste citations formatted in AMA（American Medical Association），MLA（Modern Language Association），APA（American Psychological Association），and NLM（National Library of Medicine）。In addition，the box has links at the bottom that can be used to download the citation information in NBIB format。

搜索现场描述和标记

Search field descriptions and their corresponding tags are listed in the table below.Please note，however，that the following search tags apply only to articles that have been indexed by PubMed/MEDLINE:MeSH Major Topic[MAJ]，MeSH Subheadings[SH]，MeSH Terms[MH]，GrantNumber/RNEC]]，and Supplementary Concept[NM]。Use of these tags will restrict the retrieval of search results to the MEDLINE-indexed subset of PMC。

Abstract[ab]	过滤器，过滤器filter	支付，支付[pg]
访问，访问[accn]	全Author Name[fau]	PMC Live日期[pmclivedate]
Acknowledgements[ack]	Grant Number[gr]	发布，发布日期，日期
空气净化装入	Issue[ip]	PubMed ID[pmid]
全金属板，全金属板[all]	Journal Title[ta]	参考，参考refr
Author[au]	SH Major Topic[majr]	参考检验器refa
Article Body-全部世界	SH Subheadings[sh]	分段title秒数
Article Body-关键点Terms[kwd]	SH Terms[mh]	概要，概要Concept[nm]
DOI[doi]	方法关键点Terms[meth]	文本世界[tw]
EC/RN Number[rn]	Organism标记	Title[ti]
电子，电发布日期	OrganismUnsynonymized[orgn_nosyn]	体积，体积[视图]
火焰/表Caption[capt]

标题：See an alphabetical list of all the search terms for a particular search field by the index in高级搜索生成器。

Abstract[ab]

Includes all words and numbers in the abstract of an article.English language abstracts are taken directly from the published article.If an article does not have a published abstract，PMC does not create one。

访问，访问

Includes accession numbers from the GenBank sequence database that are cited in PMC articles。

Acknowledgements[ack]

Includes all words in the acknowledgement section of an article（e.g.，“National Institutes of Health[ack]”）。

辅助功能[ad]

Includes the institutional affiliation and address（including email address，when available）of the authors of the article as it appears in the journal.This field can be used to search forwork done at specific institutions（e.g.，“mayo[ad]AND clinic[ad]”）。

所有场或所有场

Includes all searchable PMC fields.However，only terms where there is no match found in one of the翻译标签或，或Indexesvia the自动定时映射process will be searched in All Fields。

Author[au]

To search for an author，enter the last name followed by a space and up to the first two initials followed by a space and，if applicable，a suffix abbreviation.Do not include a period or comma after the last name（e.g.，“fauci as oro'brien jc jr”）。Initials and suffixes may be omitted when searching。

PMC automatically truncates on an author's name to account for varying initials，e.g.，o'brien j[au]will retrieve o'brien ja，o'brien jc jr，as well as o'brien j.To turn offthis automatic truncation，enclose the author's name in double quotes and alithy g.，“o'brien j”[au]to retrieve just o'brien j。

See，See全Author Name[fau]below for more information on author searching。

Article Body-All Words[article]

Includes all words and numbers in the body of an article except for the Abstract and References。

Article Body-Key Terms[kwd]

Includes all key terms in the body of an article except for the Abstract and References。

数字对象标识符[doi]

aunique string that identifies a piece of intellectual property in an online environment.Many publishers assign DOIs to their online full text articles。

EC/RN Number[rn]

EC/RN numbers are assigned by：

• The Food and Drug Administration（FDA）Substance Registration System for Unique Ingredient Identifiers（UNIIS），e.g.，Y92 OUS2H9B
• The Enzyme Commission（EC）to designate a particular enzyme，e.g.，EC1.1.1.57
• The Chemical Abstracts Service（CAS）for Registry Numbers，e.g.，2751-14-6

EC/RN number search field includes both the Registry Number and the Related Registry Number（available in theNLM MeSH Browser）。

电子发布日期

The date of the electronic publication.Dates or date ranges must be entered using the format YYYY/MM/DD[epubdate]（e.g.，2021/04/06[epubdate]）。The month and day are optional（e.g.，2021[epubdate]or2021/03[epubdate]）。To enter a date range，insert a colon（：）between the dates（e.g.，2020:2021[epubdate]or2021/01:2021/04[epubdate]）。

Entrez Date[edat]

The date the article was added to the PMC database.Search results are displayed in Entrez Date order，i.e.，last in，first out。

Figure/Table Caption[capt]

Includes all words and numbers in the figure and table captions of an article。

过滤器过滤器

Technical tags used by PMC to qualify results.See the搜索PMCsections for examples of tagged search filters。

全Author Name[fau]

The full author names from all articles for which full names are provided to PMC from the publisher.Full author searching can be entered in natural or inverted order，e.g。，“julia s wong”or“wong julia s”。See，SeeAuthor[au]for more information on author searching。

Grant Number[gr]

公共健康服务，公共健康服务，公共健康服务，公共健康服务，公共健康服务，公共健康服务，and other national or international funding sources.The four parts of the grant data are:

1. number，e.g.，LM05545
2. PHS2-character grant abbreviation，e.g.，LM
3. institute acronym，e.g.，NLM NIH HHS
4. country，e.g.，United States

Each individual grant part can be searched using[gr]，e.g.，NIH[gr]

模具定位接头：

NIH grant numbers，e.g.，5R01CA101211-03，typically have three main parts:

1. A prefix that indicates the type of grant，e.g.，5R01。
2. An8-character serial number consisting of a2-letter NIH institute/center code and a6-digit number，e.g.，CA101211。
3. A suffix that includes additional data such as grant year。

To search foran individual NIH grant number，use the 8-character serial number and the[gr]tag（e.g.，ca101211[gr]）。

标题：For a broader search，use the 2-letter grant code assigned to an agency and the[gr]tag（e.g.，ca[gr]）。For the broadest search，use the agency abbreviation and the[gr]tag（e.g.，nci[gr]）。See，SeeGrant codes and agency abbreviationsused in grant numbers for help determining the agency abbreviation using the grant code。

See alsoFunding Supportand，andAcknowledgementsfor additional information。

Issue[ip]

The number of the journal issue in which the article is published。

Journal Title[ta]或[journal Title]

The journal title abbreviation，full journal of Biological Chemistry，0021-9258）.Ifajournal title contains parentheses or brackets，enter the name without the parentheses or brackets，e.g.，Proc（Bayl Univ Med Cent）as“Proc”。

ThePMC Journal Listis available to browse journal titles，holdings and embargo information.Or use the日记账数据库look up the full name，abbreviation，and ISSN number of a journal。

SH Major Topic[majr]

A MeSH term that is one of the main topics discussed in the article.SeeSH Termsbelow。

SH Subheadings[sh]or[subHeading]

MeSH Subheadings are used with MeSH terms to help describe more completely a particular aspect of a subject.For example，the drug therapy of asthma is displayed asthma/drug therapy.See MeSH/Subheading Combinations。

The MeSH Subheading field allows users to“free float”Subheadings，e.g.，“hypertension[mh]AND toxicity[sh]”。

-SH Subheadings automatically include the more specific Subheading terms under the term in a search.To turn off this automatic feature，use the search syntax[sh:noexp]，e.g.，“therapy[sh:noexp]”。

In addition，you can enter the MEDLINE two-letter MeSH Subheading abbreviations rather than spelling out the Subheading（e.g.，dh[sh]=diet therapy[sh]）。See，SeePubMed Help:MeSH Subheadingsfor a full list of abbreviations。

SH Terms[mh]or[MeSH Terms]

NLM's中间项目标题controlled vocabulary of biomedical terms that is used to describe the subject of each journal article in MEDLINE.MeSH contains more than23，000terms and is updated annually to reflect changes in medicine and medical terminology。SH terms are arranged hierarchically by subject categories with more specific terms arranged beneath broader terms.Entrez allows you to view this hierararrchy and select terms for searching in theSH database。

Skilled subject analysts examine journal articles and assign to each the most specific MeSH terms applicable，typically 10to12.Applying the MeSH vocabulary ensures that articles are uniformly indexed by subject，whatever the author's words。

Notes on MeSH Terms and Major MeSH Topic Search Fields：

To search the term only as a MeSH term，it must be tagged using the search field，e.g。，[mh]for MeSH Terms or[majr]for MeSH Major Topic。A tagged term is checked against thePMC MeSH translation tableand mapped to the appropriate MeSH term.Some concepts may map to two or more MeSH terms.To turn off this mapping，enclose the MeSH term in double quotes and tag with[mh]，e.g.，“cold”[mh]。

MeSH terms are arranged hierarchically by subject categories with more specific terms arranged beneath broader terms.MeSH terms in PMC automatically include the more specific MeSH terms in a search.For more detailed information about MeSH vocabulary including the hierarc structure，please the ase see theSH home page。

ESH/Subheading Combinations：

To directly attach MeSH subheadings，use the format MeSH Term/Subheading，e.g。，“neoplasms/diet therapy”。You may also use the MEDLINE two-letter MeSH subheading abbreviations，e.g.，neoplasms/dh.The[mh]tag is not required，however[majr]may be used，e.g.，“plants/genetics[majr]”。Only one subheading may be directly attached to a MeSH term。

For a MeSH/Subheading combination，PMC always includes the more specific terms arranged beneath broader terms for the MeSH term and also includes the more specific terms arranged beneath broader subheadings.The broader subheading，or one of its subheadings，will be directly attached to the MeSHading of for ple，“hypertension/therapy”also retrieves“hypertension/diet therapy”；“hypertension/drug therapy”；“hypertension，malignant/therapy”；“hypertension，malignant/drug therapy”，and so on，as well as“hypertension/therapy”。

To turn off the automatic inclusion of the more specific terms，use the syntax[field:noexp]，e.g.，hypertension[mh:noexp]，orhypertension[majr:noexp]，orhypertension/therapy[mh:noexp]。The latter example turns off the more specific terms in both parts，searching for only the one Subheading therapy attached directly to only the one MeSH term hypertension。

SH terms can be selected for searching in the drop-down menu in the高级搜索生成器。

Methods-Key Terms[meth]

Key terms from the methods section of the article abstract。

Organism[orgn]

Contains the scientific and common names for the organisms in the NCBI taxonomy database that are found in PMC articles.The NCBI taxonomy database only includes species that are represented in the public sequence databases，so many of the organismmentioned in PMC articles will not be found in thin to in in in in in in decut in in downs， matches to scientific names are required to add PMC articles to this index-common names in this field will only retrieve articles thatmention the corresponding scientific name。

By default，the PMC organism search is“unexpanded”and does not include more specific terms.The query mammalia[orgn]will only retrieve articles that explicitly mention mammalia.The query mammalia[orgn:exp]will retrieve articles thatmention any of the specof mammals。

Organism Unsynonymized[orgn_nosyn]

Organism names that are identified as synonyms in the NCBI taxonomy database will retrieve the same set of articles in the PMC Organism index（e.g.，“Danio rerio[orgn]”=“Brachydanio rerio[orgn]”）。The Organism unsynonymized index will only retrieve articles that use the exact name as given。

支付，支付

Enter only the first page number on which the article appears.The result will display the full pagination of the article，but this field is searchable using only the first page number。

PMC Live Date[pmclivedate]

Date the article was first available in PMC.Dates or date ranges must be entered using the format YYYY/MM/DD，e.g.“2021/04/06[pmclivedate]”.The month and day are optional（e.g.，“2021[pmclivedate]”or“2021/03[pmclivedate]”）.Toenter a date range，insert a colon（：）between each date（e.g.，“2020:2021[pmclivedate]”or“2021/01:2021/04[pmclivedate]”）。

发布日期

The date that the article was published.Dates or date ranges must be searched using the format YYYY/MM/DD，e.g.“1998/03/06[pubdate]”.The month and day are optional（e.g.，“2021[pubdate]”或“2021/03[pubdate]”）。

To enter a date range，insert a colon（：）between each date（e.g.，“2019:2021[pubdate]”or“2021/01:2021/04[pubdate]”）。

使用的following format to search X days，months，or years immediately preceding today's date where X=numeric value:

• “last X days”[pubdate]
• “last X months”[pubdate]
• “last X year”[pubdate]

标题：The display of the publication date depends on the publication format of the journal（e.g.，electronic，print）.Some journals include just the year，whereas others include the year plus month plus day.Some journals use the year and season（e.g。，Winter2021）.The publication date in the citation is recorded as it is provided to PMC from the publisher.It is recommended that you search only by year（e.g.，“2021[pubdate]”or“2019:2021[pubdate]”）。

PubMed ID[pmid]

Unique identifier for the PubMed record for a PMC article。

参考，参考

Includes words and numbers in the titles in an article references section。

参考审计者

Includes authors cited in an article references section。PMC references do not list the full author name.The format to search for a reference author is the same as articleAuthorsearching。

分段标题

Includes words and numbers in an article section title。

Supplementary Concept[nm]

Includes chemical，protocol or disease terms.Synonyms to the supplementary concepts will automatically map when tagged with[nm]。This field was implemented in mid-1980；however，many chemical name s are searchable as MeSH terms before that date。

文本世界或文本世界

Includes all words and numbers in the title，abstract and article body，as well as in table and figure captions and in the article reference section。

标题，标题

Words and numbers included in the title of an article。

体积，体积

The number of the journal volume in which an article is published。

Appendices

自动Term映射｜Stopwords｜翻译表｜Author Index｜Cookies｜Character Conversions｜PMC URL格式

自动Term映射

Terms not followed bya搜索表在搜索box are matched（in this order）against thePMC MeSH（Medical Subject Headings）translation table，the焦散反射表，the全自动平衡表，and theAuthor index。

列车停车场，列车停车场可伸缩性the mapping process is complete and does not continue to the next translation table。

报告程序自动测试映射：

If you want to report a translation that does not seem accurate for your search topic，please write to thePMC Help Deskwith the information。

Stopwords

PMC searches use the same stopwords that are used in PubMed.Stopwords are common，but uninformative words such as“a”or“about”that are eliminated from searches.SeePubMed Stopwordsfor the list。

翻译表

列车自动跟踪横向阻力测量装置MeSH（Medical Subject Headings）translation table，a焦散反射表，the全自动平衡表。

PMC MeSH翻译表

The PMC MeSH translation table contains：

• ESHterms
• The See-Reference mappings for MeSH terms
• SH Subheadings
• Terms derived from the统一度量语言系统（UMLS）在进气阀系统中，进气阀或进气阀
• Supplementary concept（substance）names and their synonyms

If a match is found in this translation table，the term will be searched as MeSH（which includes the MeSH term and any specific terms indented under that term in theSH hierarchy），and in all fields.For example，if you enter“vitamin c”（without quotes）in the query box，PMC will translate this search to：“ascorbic acid”[MeSH Terms]OR vitaminc[Text Word]

日记账翻译表

“日记账translation table contains”：

• 全封闭式title
• title abbreviation
• ISSN number

These will automatically map to the journal abbreviation that is used to search journals in PMC.For example，if you enter the journal title“annals of botany”

完全审计/翻译表

The Full Author translation table contains full author names from all articles for which full names are provided to PMC from the publisher。

Author Index

在…前，在…前PMC MeSH translation tableor the，or the焦散反射表and is not a single term，PMC checks the author index for a match.When combining multiple authors，to avoid a match with full author names，include initials or use the[au]search tag，e.g.，ryan[au]AND james[au]。

Cookies

A“cookie”is information stored by a web server on your computer.See theNLM专用策略for additional information。

In the case of PMC，cookies are used to store information about your interactions that may be needed later to perform a particular function。

To use interactive features，you need to enable cookies on your computer.Please consult your browser's Help for information on enabling cookies。

If you have problems using cookie-dependent features of PMC even after enabling cookies，possible reasons may include:

• Cookies are blocked by your provider or institution.Check with your Internet provider and/or the system administrator at your institution to see if cookies can be accepted。
• Your computer's date and time settings are incorrect.Check your computer's time settings to ensure that they are correct。

Character Conversions

When running a search that includes special characters（e.g.，pound sign，dollar sign），PMC uses certain characters to have specific meaning，whereas others are converted to spaces.（SeePubMed Character Conversions家庭，in the abstracts and full text of PMC articles，all characters are represented as accurately as possible

PMC URL格式

PMC's URL format is consistent with most other NCBI sites。

In general，the first URL path segment will identify the resource type.Subsequent path segments identify the specific resource，and sometimes sub-resources.Query string parameters are used to filter or refine results，and to specify the response format。

In many cases，there are multiple URLs that will access the same resource.In these cases，we identify one as the canonical URL（shown底部，底部in the table below），and use of the ancillary URLs will cause a redirect to the canonical one。

资源类型	URL（s）
List of journals	/journals/
列出的故障补偿search	/journals/？term=respiratory
A specific journal archive	/journals/2/ /journals/domain/pnas/ /journals/jrid/32141/ /journals/issn/1091-6490/ /ivip/1091-6490/
Latest issue	/journals/2/latest/
Issue	/issues/157490/ /ivip/0021-9738/117/8/
Article full text HTML	/articles/PMC 2814059/ /articles/PMC 2814059 /articles/2814059/ /articles/2814059.3/ /articles/pmid/20126278/ /articles/doi/10.1371/currents。RRN1147 /ivip/0021-9738/117/9/2380/ Note：Unlike the other formats，the DOI format above does not allow an optional slash at the end because DOIs can contain slashes.A trailing slash would be interpreted as being part of the DOI。
Article full text PDF	/articles/PMC 2150930/pdf/
火焰，火焰	/articles/PMC 2278217/figure/F5/
Table	/articles/PMC 2278217/table/T1/
Article manuscript	/articles/mid/NiHMS20955/
Cited-by list	/articles/PMC 369838/citedby/
URLs are relative to www.ncbi.nlm.nih.gov/pmc。 The URL formats shown in底部，底部identify the canonical URLs；use of the ancillary URLs will cause a redirect to the canonical URL.Note that the trailing slash is optional（except for the DOI format as noted above，where a trailing slash would be interpreted as being part of the DOI.The canonical URL format will almost always end in a trailing slash。