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Dynamic banding (RBG-GBG) using pulse 5-bromodeoxyuridine (5-BrdU) incorporation during part of the last S-phase before harvesting has been used in prenatal investigations. This method has already been routinely applied in 1344 cytogenetic investigations. GBG and RBG bandings produced almost identical patterns to classical G- and R-banding methods except for heterochromatic portions and some euchromatic segments. Nevertheless, these discordances may be somewhat helpful for cytogenetic diagnosis (i.e., X numerical abnormalities). The results showed particularly good contrast and staining; 5-BrdU incorporation did not prevent additional staining. Likewise, previous RBG or GBG disclosure allowed further chromosomal identification with C-banding or nucleolar organizer staining. Simplicity and reproducibility were very helpful in cases with a low mitotic index. 5-BrdU had no significant effect on in-vitro damage because only 0.31 per cent of cells were affected; so, we believe that dynamic banding should be used more extensively in cytogenetic investigations. Moreover, the staining and contrast qualities were very suitable for automatic methods of analysis now in use: i.e., metaphase finding and computer-assisted karyogram creation. 相似文献
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龙岩市部分自来水厂在2018年开始将二氧化氯消毒工艺和液氯消毒工艺改为次氯酸钠发生器系统消毒工艺.本文分析对比了两个水厂改造前后一年的实际运行情况.结果表明使用次氯酸钠发生器系统不会降低消毒效果,水中微生物指标可达到《生活饮用水卫生标准》要求;较智能化,节省人工,管理简便;投加次氯酸钠溶液能提升出厂水pH值,减少NaO... 相似文献
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Although researchers have often found positive relationships between organizational citizenship behavior (OCB) and performance rating, very few studies have scrutinized the team contexts in which such relationships exist. This study examines how OCB influences job performance ratings within different team cultures, as measured by team collectivism and individualism. On the basis of multilevel data collected from 81 teams working at a multinational bank in Hong Kong, team collectivism and individualism were found to moderate the OCB–performance rating relationship such that OCB targeting individuals improved rated performance in highly collectivistic teams only, whereas only organizational OCB produced a significant improvement in highly individualistic teams. The implications of these findings and directions for future research directions are discussed here. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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The endocrine and reproductive function of the female Yucheng adolescents prenatally exposed to PCBs/PCDFs 总被引:1,自引:0,他引:1
BACKGROUND: Polychlorinated biphenyls (PCBs) and related compounds such as polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-dioxins (PCDDs) alter sexual maturation and endocrine function in animals. In 1978-1979, a mass poisoning occurred in central Taiwan from cooking oil contaminated by heat-degraded PCBs and oxidated compounds PCDFs. We tested the hypothesis that in utero exposed to PCBs/PCDFs alter sexual maturation, endocrine, and reproductive function in the human pubescent females. METHODS: In 1997-1999, girls aged 13-19 years, born to mothers exposed to PCBs/PCDFs, was invited to participate in the study. Menstruation characteristic was recorded daily for 84 days and serum levels of estradiol, LH, FSH, and testosterone were measured on the 3rd day of menstruation. RESULTS: A total of 17 exposed girls and controls participated, the exposed girls reported shorter mean duration of bleeding per cycle than 16 unexposed (5.5 vs 6.5 days, P=0.0055). There was a higher rate of irregular menstrual cycle in the exposed girls (40% vs 0%, P=0.018). Serum levels of estradiol (P=0.016) and FSH (P=0.061) were higher in exposed girls as compared to controls. CONCLUSIONS: We conclude that prenatal exposure to PCBs/PCDFs resulted in abnormal menstruation and higher estradiol and FSH levels in follicular phase of menstrual cycle in adolescent girls. 相似文献
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通过观察活性污泥的色、嗅、数量、质量和微生物生长等情况,判断活性污泥性状的优劣以控制污水处理系统的运行状况,并查明出现异常的原因,达到污水处理的最佳效果。 相似文献
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