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Biomedical subjects

R S Li

Publications and source records attributed to R S Li.

36 records · Page 2Linked to original sources
PubMed1989

[Effect of oxymatrine on beating of cultured myocardial cells in vitro].

Oxymatrine (OM), extracted from Sophora alopecuroides L, increased the contractility of the left heart atrium and decreased the spontaneous beating rate of right atrium of rabbit as described in our previous paper. The effect of OM on the beating rate of cultured rat myocardial cells was observed in the present study by a method of recording photoelectric energy transformation. OM 50 mumol/L decreased the beating rate of the myocytes by 50 +/- 27% 15 min after administration and also antagonized the positive chronotropic effect of isoproterenol 1.5 mumol/L, while the negative chronotropic effect of OM was completely abolished by prazosin. However, OM 250 mumol/L accelerated the beating rate of myocytes, which was cancelled by propranolol. These results suggest that OM has biphasic effects on cultured rat myocytes: slowing rate by alpha-adrenoceptor stimulation with 50 mumol/L concentration and accelerating rate by beta-adrenoceptor stimulation with 250 mumol/L concentration.

Alkaloids↗
PubMed1989

Nutritional status in Linxian, China: effects of season and supplementation.

The ability of a supplement to counteract seasonal alterations in nutritional status for certain vitamins was studied in Linxian, an area in northern China with high rates of esophageal cancer. 150 subjects took one daily pill from April to August (16 weeks), whereas 50 subjects did not take any supplement. Deficiencies of ascorbic acid, riboflavin, folic acid, retinol and tocopherol were prevalent at the outset of the study. The changes in diet occurring between the end of the winter (April) and the start of the autumn vegetable harvest (August) were reflected in greatly improved ascorbic acid status and slightly improved riboflavin status. Plasma retinol, tocopherol, alpha-carotene and beta-carotene were little affected by season, whereas erythrocyte folate levels declined. The ascorbic acid, riboflavin, folate, retinol and tocopherol status of the supplemented subjects was significantly improved. After 16 weeks of supplementation, erythrocyte folate levels of subjects with esophageal dysplasia were improved but remained significantly lower than those of normal supplemented subjects, targeting folic acid as a nutrient of particular interest in this precancerous condition.

Anthropometry↗
PubMedDate not supplied

Characteristics of a cell line established from a Chinese patient with a squamous carcinoma of the uterine cervix.

A new cell line, CC3/CUHK3, was established from a squamous carcinoma of the uterine cervix from a Chinese patient. Light microscopy of the cell line revealed keratin and electron microscopy demonstrated tonofilaments and desmosomes, thereby confirming its epithelial nature. The population doubling time of CC3/CUHK3, estimated from the exponential growth phase of the growth curve established from the cell line was 42 hours. When the tumour cells were inoculated into athymic mouse, a tumour, microscopically diagnosed as a well-differentiated carcinoma, developed. These cells are highly invasive in vitro.

Animals↗