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21.
Virus Genes - Rotavirus A is a dynamically evolving pathogen causing acute gastroenteritis in children during the first years of life. In the present study, we conducted a phylodynamic analysis...  相似文献   
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Benzophenone-3 is a putative endocrine disrupting chemical and common ingredient in sunscreens. The potential of endocrine disrupting chemicals to act as agonists or antagonists in critical hormonally regulated processes, such as mammary gland development and mammary tumorigenesis, demands evaluation of its potential in promoting breast cancer. This study identifies the effects of BP-3 on mammary tumorigenesis with high-fat diet during puberty versus adulthood in Trp53-null transplant BALB/c mice. Benzophenone-3 exposure yielded levels in urine similar to humans subjected to heavy topical sunscreen exposure. Benzophenone-3 was protective for epithelial tumorigenesis in mice fed lifelong low-fat diet, while promotional for epithelial tumorigenesis in mice fed adult high-fat diet. Benzophenone-3 increased tumor cell proliferation, decreased tumor cell apoptosis, and increased tumor vascularity dependent on specific dietary regimen and tumor histopathology. Even in instances of an ostensibly protective effect, other parameters suggest greater risk. Although benzophenone-3 seemed protective on low-fat diet, spindle cell tumors arising in these mice showed increased proliferation and decreased apoptosis. This points to a need for further studies of benzophenone-3 in both animal models and humans as a potential breast cancer risk factor, as well as a more general need to evaluate endocrine disrupting chemicals in varying dietary contexts.  相似文献   
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Vertical transmission of tick-borne encephalitis virus (TBEV) between generations of the small rodents—red voles Myodes rutilus Pallas (previously known as Clethrionomys rutilus Pallas) was shown for naturally infected reservoir hosts and after experimental infection with different sublethal doses of the viral strains. For wild red voles and for their progeny born in 240–280 days after experimental infection of their parents the TBEV was detected in up to 90% of samples by RT-PCR, ELISA and bioassays. Small amounts of the TBEV RNA found in embryos, placenta and blood cells could serve as evidence of prenatal transmission. Postnatal transfer of the virus might occur through the rodent milk. Analysis of the TBEV E gene nucleotide sequences of RT-PCR products revealed missense mutations resulting in amino acid substitution K280Q in newborn red vole in comparison with its parent female.Taken together, the data confirmed the TBEV vertical transmission among generations of its adapted mammal reservoir hosts. The virus transfer might occur before, during and/or after birth of the small rodents with high frequencies. In the wild it could provide the TBEV long-term persistence in mammal hosts without an (any) involvement of arthropod vectors thus selecting dangerous mammal-adapted variants.  相似文献   
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The paper deals with the studies of the levels of lead in the biological media in women in labour and their neonatal infants who live in poor environmental areas. A comparison was made of the levels of lead in the biological media of the women in labour and neonates from the experimental and control groups. There was a relationship between the levels of lead in the biological media of the newborn and the mother. A total of 7 different biosubstrates from the women in labour and neonatal babies were examined. The studies were made by atomic absorption spectrophotometry on a Perkin Elmer 3110 device.  相似文献   
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Two transplantable differentiated mouse hepatocarcinomas were obtained in B6 D2 F1 mice from primary tumors induced by initiation (NDEA)-promotion (phenobarbital) protocol. Both HC were slowly growing with time from passage to passage of 5-7 months (s-HC). A fast-growing variant with time between passages of 2-3 weeks appeared in one mouse on the third passage (f-HC). The three HC strains constantly retained their phenotype. The s-HCs were characterized by prominent cell polarity according to organization of the cytoskeleton and distribution of domain-specific membrane-associated markers. Cell polarity was completely destroyed in the fast-growing variant. Cell adhesion in the latter tumor was very low. An in vitro growing strain of f-HC was easily obtained enabling experimental study of regulation of progression in HCs.  相似文献   
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The results of bicycle ergometry testing were studied in 20 patients with diabetes mellitus of type II without clinical signs of circulatory insufficiency, 21 patients with postinfarction cardiosclerosis with undisturbed carbohydrate tolerance, and in 18 healthy persons. The blood level of glucose in patients with diabetes mellitus was investigated on an empty stomach and 30, 60 and 120 min. after physical exercising. Similar changes of bicycle ergometry results were found in diabetic and CHD patients. In compensation of diabetes in response to graded physical exercise glycemic changes were absent, in decompensation glycemia increased in 30 and 60 min. and returned to the basal level 120 min. after testing. Since the results of bicycle exercises in diabetic (compensated) and CHD patients were the same, the principles of their physical rehabilitation must be identical. In patients with decompensated diabetes mellitus a hyperglycemic reaction to graded physical exercise serves the basis for reduction of motor activity in patients with decompensated diabetes mellitus.  相似文献   
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