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排序方式: 共有689条查询结果,搜索用时 31 毫秒
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目的:为进一步降低孕产妇死亡率提供科学依据,总结大理市孕产妇系统管理工作的经验教训.方法:回顾性分析大理市15a孕产妇死亡病例.结果:大理市15a孕产妇死亡率逐年下降,从1986年的127.4/10万降至2000年的49.4/10万.死亡原因前五位依次为产科出血、妊高症、产褥感染、羊水栓塞、妊娠合并心脏病.结论:本市的孕产妇死亡原因主要与医疗保健人员知识技能水平相关、家庭个人知识水平及经济状况相关. 相似文献
3.
为了实现医学可视化的网络应用,提出一种基于小波描述子的表面渲染数据渐进传输方法.首先针对用于表面重建的序列平面轮廓为周期序列的特点,提出数字轮廓小波描述子的概念.基于小波描述子进行渐进传输的基本思想是,在发送端将轮廓采用小波描述子表示,然后对这些小波描述子系数序列渐进发送.在接收端,利用陆续收到的描述子系数序列重构轮廓,进行表面重建与渲染,重建精度和渲染效果随着不断收到‘细节'部分数据而得到改善并最终达到发送端的效果.该方法可以在数据无损传输的情况下,降低对传输网络带宽的要求,文中实验研究表明了方法的可行性. 相似文献
4.
目的:介绍心肌细胞培养方法和研究比色分析法测定活心肌细胞.方法:接种不同数量细胞培养后行噻唑兰(MTT)比色分析;正常培养、含不同浓度维拉帕米培养的细胞行MTT代谢比色分析,并测乳酸脱氢酶(LDH)活性.结果:比色值与接种细胞数量、细胞释放的LDH活性呈高度相关(r=0.996、-0.986,P<0.01).结论:MTT比色分析法可用于测定活心肌细胞. 相似文献
5.
Christian P West KP Khatry SK Kimbrough-Pradhan E LeClerq SC Katz J Shrestha SR Dali SM Sommer A 《American journal of epidemiology》2000,152(6):542-547
Night blindness due to vitamin A deficiency is common during pregnancy among women in Nepal. The authors assessed the risk of maternal death during and after a pregnancy with night blindness among women participating in a cluster-randomized, placebo-controlled vitamin A and beta-carotene supplementation trial in Nepal from July 1994 to September 1997. Subjects were 877 women with night blindness and 9,545 women without night blindness during pregnancy. Women were followed from the time they declared that they were pregnant through the end of the study, representing a median follow-up of 90 weeks (interquartile range: 64-121 weeks). Mortality of night-blind women in the placebo group was 3,601 per 100,000 pregnancies. In comparison, the relative risk of dying among nonnight-blind women in the placebo group was 0.26 (95% confidence interval (CI): 0.13, 0.55), and the relative risk among women with or without night blindness in the vitamin A/beta-carotene group was 0.32 (95% CI: 0.10, 0.91) and 0.18 (95% CI: 0.09, 0.36), respectively. Night-blind women were five times (95% CI: 2.20, 10.58) more likely to die from infections than were women who were not night blind. These findings show that night blindness during pregnancy is a risk factor of both short- and long-term mortality among women. Vitamin A/beta-carotene supplementation ameliorates this risk to a large extent. 相似文献
6.
Christian P West KP Khatry SK Katz J LeClerq SC Kimbrough-Pradhan E Dali SM Shrestha SR 《The Journal of nutrition》2000,130(11):2675-2682
The contribution of nutritional interventions to the reduction in maternal morbidity rates in developing countries is not well known. We assessed the impact of weekly vitamin A and beta-carotene supplementation on the prevalence of pregnancy and postpartum illness symptoms among 15,832 Nepali women in a placebo-controlled, double-masked, cluster-randomized trial. There was no impact of either supplement on morbidity rates reported up to 28 wk of gestation, inclusive. However, in late pregnancy (>28 wk), symptoms of nausea, faintness and night blindness were reduced with vitamin A, but not beta-carotene, supplementation. Vitamin A supplementation shortened the length of labor by 1.5 h 50 min among nulliparous and multiparous women, respectively. Both interventions reduced the postpartum prevalence of at least four loose stools and night blindness. beta-Carotene supplementation also reduced symptoms of high fever postpartum. The mean number of days of any reported illness symptoms was 3-4 per wk throughout pregnancy. Among women receiving vitamin A, the total number of days of illness symptoms accrued over the last 12 wk of pregnancy was lower by 5 d compared with the placebo recipients. We found the burden of pregnancy-related illness symptoms to be high in this rural area of Nepal where antenatal care is poor and most deliveries occur at home. Maternal vitamin A or beta-carotene supplementation resulted in a reduction in the prevalence of selected illness symptoms during late pregnancy, at the time of birth and during 6 mo postpartum, suggesting that a diet adequate in vitamin A may be important for improving women's reproductive health. 相似文献
7.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献
8.
目的 调查云南省大理小型哺乳动物的种类。方法 2 0 0 0~ 2 0 0 3年对云南省大理小型哺乳动物种类和分布进行了调查。结果 捕获小型哺乳动物 2 2 68只 ,初步查明的种类有 2 4种 ,隶属 3目 6科 13属 ,以啮齿动物为主。结论 大理小型哺乳动物种类丰富 ,至少 17种小兽与多种动物源性疾病的传播有关 相似文献
9.
吉林口岸2001~2004年出入境人员梅毒检测结果分析 总被引:3,自引:0,他引:3
目的探讨吉林出入境人员梅毒感染的流行病学变化。方法用RPR方法对出入境人员进行初步筛选,然后用TPHA方法来确认;对65例梅毒感染者进行流行特征的分析。结果 2001、 2002、2003和2004年梅检出率分别为0.014%,0.053%,0.152%,0.221%,出入境人员的梅毒感染率呈着年上升趋势。不同职业的人群感染情况不同,其中劳务人员和商务人员分别占感染组的 49.23%和12.31%。结论梅毒的感染率呈逐年上升的趋势;劳务人员和商务人员比其他职业人员的感染情况严重。 相似文献
10.
目的:观察降糖明目汤对背景期糖尿病视网膜病变(BDR)模型兔的sICAM-1、NF-κB的影响。方法:BDR模型兔随机分为模型组、降糖明目汤治疗组和西药导升明对照组,检测血清sICAM-1、视网膜NF-κBp65表达,并与正常组比较。结果:模型组实验兔血清sICAM-1浓度明显高于中药治疗组、西药对照组和正常组(P<0.01);西药对照组与中药治疗组、正常组比较有极显著性差异(P<0.01);但中药治疗组与正常组比较无显著性差异(P>0.05)。模型组实验兔视网膜出现少量新生血管,且视网膜NF-κBp65强表达,与正常组、中药治疗组比较,有极显著差异(P<0.01),与西药对照组比较无显著性差异(P>0.05);中药治疗组与西药对照组比较有显著性差异(P<0.05)。中药治疗组与正常组比较无显著性差异(P>0.05)。结论:中药降糖明目汤具有一定的抑制NF-κBp65的表达,降低血清sICAM-1浓度的作用。 相似文献