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991.
Combined exposure of mice to a mixture of chemicals in small quantities and gamma-radiation at a total dose of 30 sGy cause partial summation of biological effects assessed by cytogenetic disorders in nuclear cells of the bone marrow and changes in erythrocyte metabolism. The level of cytogenetic damages in bone marrow cells remained increased till day 14 of recovery, whereas following exposure to chemicals or radiation alone the number of chromosomal aberrations (ChA) was nearly same as in control at this point of recovery The anaphase method showed prevalence of ChA in the form of fragments over bridges in marrow karyocites. The combination of factors suppressed energy-producing processes in erythrocytes (reliable reductions in lactate dehydrogenase and lactate) and activated oxidation processes (reliable decrease in reduced glutathione). Functional shifts in erythrocyte metabolism persisted till day 30 of recovery Based on results of the investigation, functional status of organism following low-intensity exposures can be assessed, along with cytogenetic, also by indices of erythrocyte metabolism.  相似文献   
992.
The paper presents the results of experimental and clinical testing of 3-hydroxypyridine derivatives (emoxipin, mexidol and new compounds) various extreme conditions (hypoxia, hyper- and hypothermia, vibration, hypokinesia, ionizing and nonionizing radiation and others). Analysis of the results led to the conclusion that 3-hydroxipiridine derivatives are a group of compounds worthy of further in-depth investigations in a broad range of extreme conditions in order to assess their potential use in development of new medical protectors of humans and animals facing extreme factors of various nature.  相似文献   
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The aim of the study was to assess both p27 and p53 expression in the stromal and epithelial component of carcinosarcoma and to assess if their expression in the latter is different than in endometrial carcinoma. Immunohistochemical staining for p27 and p53 was performed on paraffin-embedded tissue blocks of 18 uterine specimens with carcinosarcoma and their expression assessed. Their expression in the epithelial element was also compared to that in 35 paraffin-embedded tissue blocks of endometrial endometrioid carcinoma. Reduced p27 expression was observed in a similarly high proportion of the stromal (77.8%) as well as of the epithelial component (66.7%) of carcinosarcoma. Although statistically not significant, the proportion of reduced p27 expression in endometrial carcinoma (85.7%) was higher than in the epithelial element of carcinosarcoma. The percentage of p53 overexpression in both elements of carcinosarcomas and in endometrial carcinomas was low and also similar (27.8 and 20.0%, respectively). Our results indicate that reduced p27 expression is common and p53 overexpression is infrequent in carcinosarcoma. Their similar rates of expression in the stromal and epithelial elements of the tumor support the contention of a monoclonal origin of carcinosarcoma. Unexpectedly, reduced p27 expression is more common in endometrial carcinoma than in the epithelial element of carcinosarcoma, in spite of the less favorable prognosticators and outcome in the latter. Further studies of p27 expression in carcinosarcoma are indicated to establish its clinical value in this aggressive malignancy.  相似文献   
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The worldwide shortage of organs for transplantation makes it important to understand why some oppose donation. Attitudes vary with religion and ethnicity. Accordingly, we undertook a qualitative study of the attitudes of 141 U.K. Muslim Indo-Asians to organ donation. Participants were observed, focus group discussions held and in-depth individual interviews conducted. We identified a high level of alienation from the health care system in general. With respect to organ donation in particular, its importance was generally discounted, often in deference to authority figures within the community who appeared negatively disposed. The culture-specific issues arguing against donation included a sense of the sacredness of the body, a fatalistic approach to illness, a belief that organs took on an independent role as 'witnesses' to an individual's life on Judgement Day and an anxiety that the donor would have no control of the probity of the recipient of an organ. We believe these data suggest a need to improve in a culturally sensitive fashion the provision of health information provided to this community.  相似文献   
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