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61.
Knowledge,attitude and practice among Health Visitors in the United Kingdom toward children's oral health
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金石穿胶囊对致石豚鼠胆汁主要成分的影响 总被引:5,自引:0,他引:5
目的 :研究金石穿对致石豚鼠胆汁中几种主要化学成分的影响 ,以确定其防治胆石症的疗效。方法 :随机将 6 0只实验豚鼠分为正常组、模型对照组、胆石通组、金石穿组 ,用致石饲料诱发豚鼠胆囊结石模型 ,喂养一段时间后处死豚鼠 ,取胆汁 ,测定其胆汁中胆红素 (Bi L)、胆固醇 (Cho)、钙离子 (Ca2 )的含量。结果 :金石穿组胆汁中Cho、Bi L、Ca2 浓度均降低。结论 :金石穿能有效降低致石豚鼠成石率 ,具有明显的防治胆石症的作用 相似文献
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Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
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人芽囊原虫在不同培养基中生长状况的观察 总被引:2,自引:1,他引:2
目的筛选培养人芽囊原虫的最适培养基。方法将同一株人芽囊原虫阳性粪便标本以2×105细胞/管接种至RPMI1640、199和LES培养基中,加入20%小牛血清及青、链霉素,pH值为7.5,放置厌氧罐中于37℃恒温培养,每24h计数,每6d转种1次。观察人芽囊原虫在3种培养基中的存活时间、虫体密度和虫体形态。结果人芽囊原虫在RPMI1640培养基中存活时间最长、虫体密度最高,虫体以空泡型多见;在LES培养基中存活时间最短、虫体密度最低,但虫体形态清晰、规则;在199培养基中存活时间和虫体密度均介于前两者之间。结论RPMI1640培养基适宜人芽囊原虫的生长繁殖,为人芽囊原虫体外培养的首选培养基;LES培养基中虫体形态清晰、规则,可用于人芽囊原虫的形态学研究;199培养基也可用于人芽囊原虫的体外培养,但不作为首选。 相似文献
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The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep. 相似文献