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991.
J L Li J L Chen M H Ouyang S Chao Y B Peng L X Lin W S Chang Y J Li 《Journal of immunological methods》1991,142(1):15-20
Anti-idiotypic antibodies are powerful reagents for the study of immunoregulation, and have potential interest as vaccines against tumors and infectious diseases. Three immunization strategies for the production of rat monoclonal anti-idiotope antibodies have been compared in this paper. Male Wistar rats were immunized i.p. and at multiple subcutaneous sites with 750 micrograms of purified monoclonal antibody against Plasmodium falciparum for three times and subsequently boosted by (1) intraperitoneal injection with 750 micrograms of the immunogen, (2) intravenous inoculation with 400 micrograms of the IgG, and (3) intrasplenic immunization with 200 micrograms of the idiotype. With the intraperitoneal boost method, the frequency of hybrids with anti-idiotope activity was 0.3-0.9% with 62.8-85.2% of the seeded wells containing hybrids. In the intravenous boost group, the percentage of hybrids demonstrating anti-idiotope activity increased to 11.0-13.3% with 80.2-97.9% of the hybrid efficiency. When immunized by the intrasplenic boost route, the frequency of anti-idiotope hybrids generated rose to 12.9-16.4% with 82.3-96.6% of the hybrid efficiency. There was no obvious effect of the boost immunizing methods on the generation of rat monoclonal anti-mouse IgG antibodies. These results indicated that the multiple-site immunization followed by intravenous or intrasplenic boost injection was an appropriate immunizing method for the production of monoclonal anti-idiotope antibodies. 相似文献
992.
人抗HBsAg噬菌体抗体Fab段基因的序列分析及表达 总被引:3,自引:0,他引:3
对已建的噬菌体抗体库分离出来的人抗-HBs克隆进行了序列分析和表达研究,发现4个克隆中3个克隆的重链和轻链完全相同,DNA序列分析表明VH分别属于VH1亚群和Ⅱ亚群,其轻链VL分别属于VλⅡ亚群和VλⅠ亚群。构建了可溶性Fab段表达载体,显示出在细菌中表达的Fab段抗体与HBsAg特异性结合,这说明所筛选出来的噬菌体抗体具有HBdisplay status 相似文献
993.
用微量马桑内酯注入Wistar大鼠左侧前肢运动皮质,造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第V层结构的改变。结果显示:癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少;灶区神经毡中突触性终末数,显著减少;突触性终末的面积分数明显减少,而树突的面积分数无变化;神经胶质突起的面积分数增加。 相似文献
994.
Marc G Weisskopf Honglei Chen Michael A Schwarzschild Ichiro Kawachi Alberto Ascherio 《Movement disorders》2003,18(6):646-651
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question. 相似文献
995.
Ying Qian Pedram Hamrah Florence Boisgerault Satoru Yamagami Sudhir Vora Gilles Benichou M Reza Dana 《Journal of interferon & cytokine research》2002,22(12):1217-1225
This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts. 相似文献
996.
肘部尺神经半脱位的解剖学和流行病学研究 总被引:6,自引:0,他引:6
目的:研究肘部尺神经半脱位的发生原因及其临床意义。方法:对100侧成人尸体肘部的尺神经位置进行解剖观察;在人群中随机调查了854位正常人肘部尺神经的位置。结果:肘管深度为7.1±0.14mm(χ±sχ)。解剖观察发现,6侧肢体的尺神经在屈肘时发生半脱位,肘管深度平均为4.8mm。854位正常人肘部尺神经半脱位发生率为8.9%(76/854)。结论:绝大多数的肘部尺神经半脱位是先天性的。肘部尺神经半脱位不一定是肘部尺神经卡压的发病原因。 相似文献
997.
牙周组织工程研究进展 总被引:10,自引:0,他引:10
牙周骨移植、引导组织再生 ( guidedtissueregeneration ,GTR)为牙周病治疗和牙周缺损修复带来新的希望 ,但在恢复牙周组织的生理结构和功能上还远未达到所期望的目标。组织工程学是近年来发展起来的一门新兴边缘学科 ,其基本方法是将体外培养的高浓度、功能相关的活细胞种植于具有良好生物相容性和生物降解性的细胞外基质材料上 ,经过一段时间的培养 ,将这种细胞与生物材料复合体植入机体病损部位以形成新的具有其原来特殊功能和形态的相应组织和器官 ,达到修复创伤和重建功能的目的。将组织工程技术引入牙周组织再生治疗 ,为牙周病的治… 相似文献
998.
我国医院药学的形成与发展 总被引:1,自引:0,他引:1
本文通过对医院药学的形成与发展的讨论,旨在确立该学科(也可说领域)的学术技术内容,尽快形成一个完善的学科,以利推进临床药物治疗学的发展,推进医药科学的进步。 相似文献
999.
研究了小麦淀粉与丙烯酰胺的接枝共聚物的物理特性和结构特征,实验结果表明:该接枝共聚物在热性质上与原淀粉有明显的区别,其糊化温度比原淀粉略低,粘度热稳定性及溶解度较原淀粉均有提高。接枝共聚反应不仅发生在淀粉颗粒的表面上,而且也发生在颗粒结构的内部,但反应仅发生在淀粉的无定型区。 相似文献
1000.
目的 研究巢湖水有机提取物致突变性。方法 单细胞凝胶电泳技术测定鱼红细胞DNA损伤效应。结果 巢湖源水引起慧星细胞的百分率最高 (5 7.2 5 % ) ,滤前水最低 (2 7.6 3% ) ,出厂水经过二次加氯后慧星细胞的百分率有所上升 (4 4 .0 0 % )。结论 巢湖源水具有潜在致突变性 ,经混凝、活性炭吸附及沉淀处理后其DNA损伤作用有所下降 ,但氯化消毒可增加水中有机提取物的DNA损伤作用。 相似文献