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71.
乙醇对人绒毛孕酮分泌的影响   总被引:1,自引:0,他引:1  
本工作利用灌流技术观察了四种不同浓度的乙醇(0.5%、1%、2.5%、5%)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。  相似文献   
72.
The hormonally responsive prolactin-inducible protein (PIP), gene is expressed in benign and malignant breast tumor tissues and in such normal exocrine organs as sweat, salivary, and lacrimal glands. In this communication we report the regional chromosome localization of the PIPgene locus to chromosome 7 by Southern hybridization to DNA from human-hamster somatic cell hybrids, and to 7q32–36 by in situ hybridization.  相似文献   
73.
目的 探讨肝脏血管瘤的手术指征和手术方法。方法 回顾性分析采用手术治疗46例肝脏血管瘤病人资料,判断其手术指征,评价不同手术方法的治疗效果厦其手术并发症发生情况。结果 46例病人中,19例采用肝叶或肝段切除术,17例出现并发症,以胸腔积液和膈下积液多见,采用血管瘤摘除术的27例病人无并发症。结论 对肝脏血管瘤直径大于5cm并有明显临床症状,或不能除外恶性肿瘤的病人可以采用手术治疗。血管瘤摘除术是安全有效、并发症少的手术方法。  相似文献   
74.
Monoclonal antibodies to the major Plasmodium falciparum merozoite surface coat and rhoptry antigens were produced. A combination of the affinity-purified polypeptides with Freund complete adjuvant which was given three times completely protected an Aotus lemurinus azure (karotype VI) monkey against homologous challenge; however, immunization with the same polypeptides with a muramyl dipeptide derivative [MDP-Lys(L18)] did not protect a second Aotus monkey, even though comparable high antibody titers were induced.  相似文献   
75.
Anticocaine catalytic antibodies   总被引:5,自引:0,他引:5  
Cocaine mediates its reinforcing and toxic actions through a "loss of function" effect at multiple receptors. The difficulties inherent in blocking a pleiotropic blocker pose a great obstacle for the classical receptor-antagonist approach and have contributed to the failure (to date) to devise specific treatments for cocaine overdose and addiction. As an alternative, we have embarked on an investigation of catalytic antibodies, a programmable class of artificial enzyme, as "peripheral blockers" -- agents designed to bind and degrade cocaine in the circulation before it partitions into the central nervous system to exert reinforcing or toxic effects. We synthesized transition-state analogs of cocaine's hydrolysis at its benzoyl ester, immunized mice, prepared hybridomas and developed the first anticocaine catalytic antibodies with the capacity to degrade cocaine to nonreinforcing, nontoxic products. We subsequently identified several families of anticocaine catalytic antibodies and found that the most potent antibody possessed sufficient activity to block cocaine-induced reinforcement, organ dysfunction and sudden death in rodent models of addiction, toxicity and overdose, respectively. With the potential to promote cessation of use, prolong abstinence and provide a treatment for acute overdose, the artificial enzyme approach comprehensively responds to the problem of cocaine.  相似文献   
76.
作者对抗体包被的红为性进行研究,发现抗体包被改变了红细胞的变形性,在我们研究的抗体量范围内,抗体量越多,红细胞的变形性越小,作者从血液流变学的角度对上述结果作了讨论,并提出了通过测定其对红细胞变形性的影响来比较准确地标定抗体效价的可能性。  相似文献   
77.
Nasopharyngeal carcinoma (NPC) provides a unique opportunity to evaluate distinctive epidemiologic features and a possible etiologic relationship with Epstein-Barr virus (EBV) in human malignancy. The lack of a uniformly accepted pathologic classification for NPC has limited the application of this data, although the World Health Organization (WHO) developed a classification that may solve this problem. Monoclonal keratin antibodies were used for staining of NPC for evaluation of its assistance in diagnosis and classification. In the present immunohistochemical study, monoclonal keratin antibodies, designated AE1, AE2, and AE3, and a polyclonal keratin antibody (RAK) were used for study of the presence of keratin in 121 cases of NPC obtained from China and the United States. AE1 monoclonal antibody, which recognizes keratin protein classes 56.5K, 50K, and 40K, was shown to be the most sensitive and specific for NPC tumor cells among the keratin antibodies studied. In addition, some different keratin expression patterns could be identified between different kinds of epithelium and different tumor groups, with possible relevance to the histogenesis of the histologic subtypes of NPC.  相似文献   
78.
We present a microtest for cell-mediated immunity, based on the use of the Tarasaki tray and calcein AM vital dye. The number of target cells needed has been reduced to 500 per test with a corresponding tenfold reduction in the number of effector cells needed. Results were read at the rate of 1 second per test using a fluorimeter attached to a microscope. Each reaction was also confirmed visually with the use of ethidium bromide as a counterstain for dead cells. The calcein AM dye used to stain the living cells was shown to have a low spontaneous leakage rate—less than 15% in 4 hours at 37°C. Dilutions of targets stained by calcein AM had a linear relationship with measured fluorescence values. NK cells, LAKs, and CTLs were readily detectable by this microtest. Quantitation of killing and kinetic analysis was readily performed with this test system. A significant positive correlation to 51Cr-release results was found. We conclude that the microtest should find wide application in studies of cell-mediated immunity.  相似文献   
79.
80.
The Microbact 24E (MB24E) system is a commercial microsystem for the identification of common clinical isolates of Enterobacteriaceae and non-fermenting Gram negative bacilli, and consists of dehydrated substrates distributed in the wells of microtitre trays. This system was compared with the API20E for the identification of 386 bacterial isolates, which included 284 clinical and 102 environmental organisms. There was 97% and 91% agreement for the identification of clinical isolates of Enterobacteriaceae and other Gram negative bacilli, respectively. The identification of environmental isolates by both systems was less satisfactory. The API20E has a more extensive database than the MB24E and is thus more reliable for the identification of rare or unusual organisms, but the MB24E is cheaper, is easy and convenient to use, and is suitable for a routine microbiology laboratory.  相似文献   
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