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31.
我国α—淀粉酶(EC3.2.1.1)生产是用枯草杆菌BF—7658菌株,它产生的酶是个复杂酶系。其中混杂的蛋白酶未见酸性蛋白酶。发酵液经热处理后,测蛋白酶活力。结果,碱性蛋白酶耐热性比中性蛋白酶强。发酵液经55℃,30分钟热处理后,碱性蛋白蛋残存活力与室温(20~25℃)下碱性蛋白酶活力相差不显著(P>0.05),而中性蛋白酶则相差显著(P<0.05)。用电泳法观察发酵液蛋白酶电泳谱型,显示两条蛋白酶区带。  相似文献   
32.
宫颈癌的治疗进展   总被引:1,自引:0,他引:1  
官颈癌是最常见的妇科恶性肿瘤之一,其发病率及死亡率仅次于乳腺癌。对官颈癌的治疗,除应力求根除疾病,提高生存率外,还应尽可能争取保留患者的生殖内分泌功能,特别是对年轻的患者。为提高宫颈癌患者的治疗效果,化疗已成为中、晚期的重要治疗手段。  相似文献   
33.
以尿嘧啶核苷和HIV-逆转录酶抑制剂扎西他宾为先导化合物,对其5-羟基进行磷酸化修饰,然后以磷原子为桥,引入各种氨基酸酯及取代苯环,从而试图克服这类药物对核苷激酶的依赖性,提高药物的生物活性,降低药物对细胞的毒性,以此为设计思路合成了7个新的核苷类衍生物,其结构经IR,1HNMR,13CNMR,MS分析确定.  相似文献   
34.
458例尿路结石成分分析   总被引:4,自引:1,他引:3  
目的 探讨西安地区尿路结石的成分状况,为临床防治提供帮助。方法对458例尿路结石标本进行化学成分测定,并结合临床资料进行比较。结果尿路结石男性发病多于女性,男、女比为2.1:1,20一50岁为高发年龄,上尿路结石明显多于下尿路结石,上、下尿路结石之比为10.5:1。结石成分以混合结石占多数,为325例(71%),其中以草酸钙,磷酸钙与尿酸的混合结石为主。对比混合性结石及单纯性结石发现,各种成分所占比例基本一致。结论结石成分分析对于了解结石成因、预防结石形成和复发具有重要的意义。  相似文献   
35.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a kind of primary myocardial disease characterized by the regional or global replacement of right ventricular myocardium by fatty and fibrolipomatous tissues. The ARVC, usually presenting with different clinical manifestations and pathological changes, were mainly seen in young men and is one of the main causes of sudden death in the young. Here two autopsied cases of Chinese men aged 30 and 23 years old who appeared healthy but died suddenly while at work are reported respectively. One of the victims had extensive and severe pathological changes in his heart involving the left ventricular wall as well as the ventricular septum and the right atrium. Not only was there a global fatty and fibrolipomatous tissue replacement of the right ventricular myocardia, but also mild sarcoplasmic coagulation in the myocardium and focal lymphocytic infiltration in the myocardial interstitium of the right ventricular wall. In addition, slight atherosclerosis of the coronary artery and intimal thickening of the sino-atrial node were observed. It is believed that there are no marked differences in the pathological changes of ARVC between Chinese patients and patients from western countries. The etiology and pathogenesis of ARVC could not be explained by a single cause or factor and they are probably related to various congenital and acquired causes or factors.  相似文献   
36.
37.
河北磁县食管癌胃癌高发人群口腔真菌分布的调查   总被引:1,自引:0,他引:1  
应用常规方法随机研究食管癌、胃癌高发的磁县人群547例的口腔真菌。结果:1.口腔真菌阳性率为68.4%,食管真菌阳性率为47.3%,前者显著高于后者(P<0.001)。2.口腔真菌以念珠菌、曲霉菌和青霉菌为主,食管真菌以曲霉菌、青霉菌和念珠菌占多数。3.口腔与食管内的产毒真菌差异无显著性意义(P>0.05)。本结果为进一步研究口腔真菌与上消化道癌及肿瘤的一级预防提供了依据。  相似文献   
38.
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   
39.
Lung cancer and prior tuberculosis infection in Shanghai   总被引:1,自引:0,他引:1  
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   
40.
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   
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