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101.
Perforation of the large bowel during colonoscopy in Singapore 总被引:1,自引:0,他引:1
The management of seven patients with colonoscopy-related perforations is described. This study demonstrates the need for an early laparotomy. A high index of suspicion is required to reach an early diagnosis. Patients with no preexisting medical problems who underwent early surgery recovered with little morbidity. In elderly patients (greater than 75 years), colonoscopic perforation can be fatal. Endoscopy should be performed with special care in such patients. 相似文献
102.
HBV DNA及HBxDNA亚片段在肝癌细胞内的整合及作用 总被引:13,自引:0,他引:13
为探讨HBVDNA及其亚基因片段HBxDN在肝细胞肝癌(HCC)中整合特点用机制,制备了地高辛标记的3.2kbHBVDNA全基因及0.59kbHBVDNA/BamHI,BglⅡBHxDNA亚基因探针。点杂交、原位杂交及Southern杂交检测HBVDNA的存在情况,筛选HBVDNA纯整合标本,以HBxDNA探针检测HBxDNA在HCC染色体的整合。结果显示HBVDNA在肝细胞内以核型为主(70%) 相似文献
103.
Intravenously injected polystyrene microspheres with functional amino groups (AP-MSs, 0.2,1.0, and 4.0 urn in diameter) were cleared from the blood very rapidly. The calculated half-lives for 0.2-, 1.0-, and 4.0-μm AP-MSs were about 55,60, and 50s; no significant differences were found with 106,107, and 108 microspheres/rat. Loading experiments showed that the liver, spleen, lung, kidney, and heart had a very high capacity to take up AP-MSs. The AP-MSs were distributed mainly to the liver, lung, and spleen, whereas other organs contained less than 1 % of injected AP-MSs. In terms of numbers of AP-MSs per gram of tissue, the highest contents were found in spleen, liver, and lung for 0.2-, 1.0-, and 4.0-um AP-MSs, respectively. There was indication of redistribution of particles from one organ to another during the first 6 h after injection. Chondroitin sulfate A (Chon) and hyaluronic acid (Hya) adsorbed or covalently linked to AP-MSs increased uptake in the liver, with Chon AP-MSs (adsorbed or linked) showing the best effect: about 25% increase compared with unadsorbed 1-μm AP-MSs. Experiments with separated cells in vitro demonstrated that 1 um AP-MSs, intravenously injected, associated only with Kupffer cells. When the microspheres were adsorbed with Chon, there was also association with liver endothelial cells. This finding indicates that conjugation of microspheres with ligands for endothelial receptors may be a useful method for directing microspheres to specific organs, even if the receptors are not by themselves phagocytic 相似文献
104.
内蒙古赤峰地区鼠疫现状和流行趋势预测及控制措施的研究 总被引:36,自引:0,他引:36
赤峰地区于1948 ̄1996年发现了16632.2km^2鼠疫自然疫源地,分布于11个旗(县、区)。目前达到控制鼠疫面积13917.8km^2,占疫源地总面积的83.68%。选取与疫源地相关的12种量经因子进行聚类分析,结果可分为:1.疫源性长存区;2.动物鼠疫间断流行区;3.鼠疫动物病控制区;4.疫源性基本消除区。同时对措施进行了探讨。 相似文献
105.
以人胚肺二倍体细胞分离出的甲型肝炎病毒作抗原,以马抗人IgM经纯化后的抗体为捕捉抗体,以纯化甲型肝炎恢复血清为特异性抗体,过碘酸钠法标记酶,以OPD为底物制成抗-HAV IgM诊断试剂盒,建立了ELISA捕捉法检测抗-HAV IgM,结果:甲型肝炎暴发点84例均为阳性,流行性出血热及健康成人各30例均为阴性。322例急性黄疸型肝炎住院患者中192例阳性(占59.6%)。12例第一病日患者11例阳性(占91.6%),证明该方法对甲型肝炎早期诊断有重要价值。 相似文献
106.
Lung cancer and prior tuberculosis infection in Shanghai 总被引:1,自引:0,他引:1
W Zheng W J Blot M L Liao Z X Wang L I Levin J J Zhao J F Fraumeni Y T Gao 《British journal of cancer》1987,56(4):501-504
In a population-based case-control study of lung cancer in Shanghai involving interviews during 1984-86 with 1,405 cancer patients and 1,495 controls, a significant 50% elevation in the risk of lung cancer, adjusted for cigarette smoking, was observed among persons who had a history of tuberculosis. Among those diagnosed with tuberculosis within the past 20 years, the risk exceeded 2.5-fold. In males the lung cancers tended to occur on the same side as the previous tuberculosis infection. For both sexes, the effect of recent tuberculosis was most apparent for adenocarcinoma and peripheral tumours. No relationship was found between lung cancer risk and the type of tuberculosis therapy, including use of isoniazid. The findings suggest that tuberculosis may predispose to lung cancer, with the association most apparent among recent survivors of the infection. 相似文献
107.
西辽河平原西北侧低山丘陵黄鼠疫源地的发现与研究 总被引:30,自引:28,他引:2
1985年首次从西辽河平原西北侧低山丘陵草原的达乌尔黄鼠及寄生蚤方形黄鼠蚤松江亚种检出4株鼠疫杆菌,到1989年共检出鼠疫菌57株,判定疫点47个。1985~1991年共检出达乌尔黄鼠鼠疫阳性血清271份,阳性率3.44%,几何平均滴度为1:99.17。疫点和血凝阳性点的空间分布约3000km~2。疫源地的主要宿主为达乌尔黄鼠,主要媒介为方形黄鼠蚤松江亚种。动物鼠疫的流行呈单峰型,流行高峰时点在5月17日,1987年为流行高峰年,坡麓为该鼠疫疫源地的频发生境。 相似文献
108.
109.
Six cases of Dp+/Gp+, 10 cases of D/G translocation, 1 case of supernumerary marker chromosome, and 1 case of Yqs were studied using molecular and cytogenetic techniques. The Ag-NOR frequencies of the Dp+ and Gp+ groups were found to be higher than those of normal controls, while their satellite association frequencies were lower. Autoradiographic silver grains were not significantly distributed along the p+ part of the marker chromosome as revealed by chromosomal in situ hybridization using an rRNA probe. This result differs from our previous report. It is suggested that there might be different mechanisms for the formation of p+ on acrocentric chromosomes. D/G translocation cases were found to have lost their NOR. A study of supernumerary marker chromosomes and Yqs cases suggested that the marker chromosome and Yqs exerted no phenotypic effect. The mechanism of their formation is discussed. 相似文献
110.
用9周-39周引产胎儿标本72例,取右耳廓石蜡切片,HE和Weitert弹性纤维染色,光镜观察其弹性软骨、弹性纤维、耳廓肌和结缔组织的发生。 相似文献