Objectives: To establish an effective method to isolate germinal vesicle frommammalian oocyte and make the isolated germinal vesicle undergo meiotic resumptionin vitro. Methods: The germinal vesicles were isolated from oocytes directly througha physical method by drawing oocyte in and out of fine-bore pipette.The isolatedgerminal vesicles were cultured in cell-free system which was prepared from the celllysate of synchronized HeLa cells.DNA fluorescence dye Hoechest 33342 was used tomonitor the condensation of chromatin during germinal vesicle breakdown. Results:The cell lysate of metaphase HeLa cell induced chromatin condensation while the cellextract of early G2 phase could not. Conclusions: The germinal vesicle can beisolated successfully in such a physical method and it can undergo chromatincondensation in vitro just as the oocyte does in vivo. Natl J Androl,2001,7(2):79～83

Blood pressure is an important index to measure the function of human cardiovascular system. In order to solve the problem of non-invasive continuous measurement of blood pressure in electronic sphygmomanometer, a non-invasive blood pressure measurement method based on EEMD (ensemble empirical mode decomposition) and ANN (artificial neural networks) were proposed. In the experiment, a total of 19500 pulse wave signals from THE MIMIC DATABASE were analyzed and subsequently the pulse wave was decomposed by EEMD. Furthermore, 10 characteristic parameters of the 4th layer decomposition signal were extracted as the input of ANN. The blood pressure corresponding to the pulse wave was taken as the output of ANN to train the BP (blood pressure) model. The error analysis of the model was carried out. The results indicated that the error of the model meets the standards of the American Association for the advancement of medical instrumentation (AAMI). Therefore, this method can be employed in noninvasive continuous measurement of blood pressure.

Background The safety of drinking water is closely related to people's health. In recent years, relevant studies have identified some health related problems with drinking water in Inner Mongolia Autonomous Region. The complex and diverse natural environment embraced by the vast jurisdiction of the region may lead to uneven drinking water quality across the region. Objective To evaluate eight chemicals including arsenic, cadmium, chromium (hexavalent), lead, mercury, fluoride, trichloromethane, and carbon tetrachloride in urban drinking water in Inner Mongolia Autonomous Region in 2021, and to provide reference for optimizing urban water supply system and ideas for further developing strategies to promote population health. Methods A total of 1228 monitoring sites were set up in urban areas of Inner Mongolia, and water samples were collected once in dry season (May) and once in wet season (August−September). Eight chemicals of interest in drinking water were detected according to the Standard examination methods for drinking water, and assessed for health risks using the health risk assessment model recommended by the United States Environmental Protection Agency (USEPA) and following the Technical guide for environmental health risk assessment of chemical exposure. Mann-Whitney U test was used to compare the concentrations of eight chemicals in urban drinking water by water seasons and water sample types. Results In 2021, a total of 2381 samples of urban drinking water were tested in the Inner Mongolia Autonomous Region, including 1195 samples in wet season and 1186 samples in dry season; 389 samples of finished water and 1992 samples of tap water. The positive rates of arsenic and fluoride were 26.25% and 96.77%, respectively. The positive rates of cadmium, chromium (hexavalent), lead, mercury, trichloromethane, and carbon tetrachloride were 6.22%, 16.63%, 6.09%, 16.67%, 18.98%, and 8.36%, respectively. The exceeding standard rate of fluoride was 4.87%. Trichloromethane and carbon tetrachloride were qualified in all samples. There were statistical differences in the concentrations of arsenic, cadmium, chromium (hexavalent), lead, and carbon tetrachloride in urban drinking water between water seasons (Z=−3.847, P<0.05; Z=2.464, P=0.014; Z=−3.129, P=0.002; Z=4.341, P<0.05; Z=4.342, P<0.05). Only fluoride concentration was found statistically different among different water sample types (Z=−2.287, P=0.022). The non-carcinogenic risks of ingestion and dermal exposure to each chemical in drinking water by water seasons and water sample types were all less than 1, but the P₉₅ total non-carcinogenic risks of oral exposure were greater than 1. The P₉₅ carcinogenic risks of oral exposure to some chemicals in drinking water by water seasons and water sample types were>10⁻⁴, which suggested carcinogenic risks, while the carcinogenic risks of dermal explore to chemicals were all less than 10⁻⁶. Conclusion In 2021, urban drinking water in Inner Mongolia Autonomous Region is generally safe, but arsenic, cadmium, chromium (hexavalent), lead, mercury, and fluoride still exceed the national limits, posing certain health risks.