Pearl

The round bead refers to the round pearl, which can be divided into three types according to the roundness, namely regular bead, round bead and near bead.

Elliptical pearl refers to the pearl with elliptical shape, and the length diameter ratio is more than 10%.

Flat bead refers to the shape of a flat surface, with one or two similar flat surfaces, such as oblate circle, oblate ellipse, cake, diamond, square, etc.

External cause

The outer mantle of the clam is stimulated by the invasion of foreign bodies (sand grains and parasites). The epidermal cells of the stimulated area take the foreign body as the nucleus and sink into the connective tissue of the outer mantle. Some of the trapped epidermal cells of the outer mantle split themselves to form pearl sacs. The pearl sacs cells secrete nacreous substance and wrap the nucleus layer by layer to form pearls. Taking foreign matter as the core is called "nucleated pearl".

Internal cause

After the outer epidermis of the mantle is stimulated by pathology, some cells divide and then separate, and then they are coated with organic substances secreted by themselves. At the same time, they gradually sink into the connective tissue of the mantle, forming pearl sacs and then pearls. Since there is no foreign matter, it is called "coreless pearl".

According to the above principle, the cultured pearls now use artificial methods to cut live epithelial cell fragments (cell fragments for short) from the mantle of pearl raising clams, and implant them into the mantle connective tissue of the clam together with the artificial nucleus prepared from the clam shell. The implanted cell fragments, depending on the nutrition provided by the connective tissue, rapidly proliferate around the artificial nucleus to form pearl sacs, It secretes nacreous substance to produce artificial nucleated pearls. The artificial nuclearless pearl is a kind of pearl that is produced by implanting only small pieces of cells, proliferating cells to form pearl sacs, and secreting nacre into the sacs.

1. Inhibition of lipofuscin and scavenging free radicals: intraperitoneal injection of pearl powder suspension 200mg/(kg. day) × 25 days in mice can significantly reduce the content of lipofuscin in cardiac muscle and brain tissue, but has no significant effect on liver tissue. The effect of PFC extracted from pearl powder of freshwater clam and its separated product on O free radical was determined by chemiluminescence method. The results showed that both of them could inhibit the luminescence, and the monomer PCM-1 after PFC purification had a strong effect, which could inhibit the free radical reaction in vivo.

2. Anti body scrub effect: intraperitoneal injection of PFC40mg/(kg. day) × 9 days in mice had significant inhibitory effect on mice subcutaneously inoculated with 8.0 × 105 sarcoma cells/ml (P<0.01), with an inhibitory rate of 34.8%; The same dose of drug can inhibit the mice inoculated with Lewis lung cancer homogenate 5.0 × 10/ml subcutaneously, and the inhibition rate is 13.89%, but there is no statistical difference. The survival time of P388/J lymphoblastic leukemia mice inoculated with the same dose of drug could be prolonged by 14.75% (P<0.05), and the spleen weight of the mice was significantly reduced by 24.12% (P<0.01). For P388/J cells cultured in vitro, the killing rates of PFC at 50 μ g/ml and 100 μ g/ml in the two dose groups after 72 hours of administration were 25.0% and 24.8% respectively (P<0.01).

3. Other effects: Pearl extract has inhibitory effect on isolated rabbit intestines.

Pearls grow in pearl mussels in the sea water. There are many essence substances and many turbid things in the growth environment of pearl mussels, but the mussels can exclude the turbid things and turn the essence into beads. The ingenuity of nature is that when we apply pearl powder on our face, it also has the effect of removing turbidity.

It is recorded in Compendium of Materia Medica that pearls can lighten freckles and chloasma. Modern medical research has also found that pearls contain a large number of trace elements, which can enhance skin activity, heat clearing and detoxification, and also have whitening, muscle growth, acne elimination, oil control, and fade spots. At the same time, it can also clean the deep skin.

Take the annoying black head for example. Because pearl powder has a very strong adsorption capacity, the dirt in the deep pores can be cleaned by the adsorption of pearl powder. In a word, pearl powder is like a strict beautician, and cannot tolerate anything that is opposite to beauty.

Traditional Chinese medicine believes that pearl powder has the results of calming the liver and suppressing yang, clearing the liver and improving eyesight, calming the heart and mind, and beautifying the face. I once read a report that a medical university in China once observed more than 100 elderly people taking pearl powder, and found that pearl powder has certain effects on relieving insomnia, upset, memory decline, etc. Of course, what is more important is its beauty retention effect.