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61.
SIDNEY SHULMAN THOMAS KEANE 《American journal of reproductive immunology (New York, N.Y. : 1989)》1981,1(2):69-72
ABSTRACT: Efforts were made to disrupt and solubilize human sperm cells and to evaluate the product for its content of infertility antibody-related antigens. In the procedure that was developed, a well-washed sperm sample is treated with 0.1 M dithiothreitol for 60 min, followed by trypsin at 0.1 mg/ml for 30 min, and then by soybean trypsin inhibitor. A mixture of DNAses I and II are added. After centrifuging, the resuspended pellet (RP) and the final supernatant (FS) show several degrees of cellular breakdown. Immunological evaluation was done with a strongly positive human serum containing sperm-head antibody. From the inhibition of sperm agglutination, we could conclude that the desired soluble antigen was obtained in the FS fraction. 相似文献
62.
嗜酸性粒细胞在小鼠体内的抗原呈递过程 总被引:8,自引:1,他引:7
目的探讨嗜酸性粒细胞(EOS)在体内能否将抗原呈递给T淋巴细胞,了解EOS在体内呈递抗原的过程和特征.方法以鸡卵清蛋白致敏和雾化吸入刺激BALB/c小鼠以诱发EOS在气道聚集.收集并纯化气道EOS以荧光素标记后注入小鼠气道,应用荧光显微镜观察EOS的移行过程.将接受气管EOS注入小鼠的气管旁淋巴结取出后制备单细胞悬液,以流式细胞仪检测其中T细胞的增殖反应并鉴定增殖T细胞的亚群.结果荧光标记的EOS注入正常鼠气道后8h即可出现于气管旁淋巴结(19.0个/mm2±1.8个/mm2),24h达高峰(59.2个/mm2±7.2个/mm2),并至少可以维持120h(29.6个/mm2±2.8个/mm2).致敏小鼠气管内注入5×105个接触过抗原的EOS1d后气管旁淋巴结增殖的T细胞百分数(6.9%±0.5%)即明显高于基础对照值(3.2%±0.3%,P<0.01),3d后达到峰值(10.8%±0.8%,P<0.01),7d以后下降(6.1%±0.6%,P<0.05).此外,EOS呈递抗原所引起的T细胞增殖反应具抗原特异性,出现增殖反应的T细胞仅限于CD4+细胞.结论气道EOS在体内可成为抗原呈递细胞,从而促使CD4细胞出现显著的增殖反应. 相似文献
63.
目的 :比较γIL - 2及抗 CD3m c Ab γIL - 2对脐血单个核细胞 (MNC)的免疫表型及细胞因子的影响。方法 :采用间接玫瑰花结法实验测定 2 3例脐血 MNC表面的分化抗原 ,EL ISA双抗夹心法测定肿瘤坏死因子 -α(TNF-α)、白介素 - 6 (IL - 6 )、白介素 - 8(IL - 8)。结果 :经γIL - 2及抗 CD3mc Ab γIL - 2激活的脐血 MNC其分化抗原发生明显变化。 1、两组与未活化相比 :CD3 、CD8 、CD16 、CD5 6 、CD19 、CD2 3 、HL A- DR↑ ,其表达 CD2 5亦均增加 ,但抗 CD3mc Ab γIL- 2激活组 >γIL- 2组 (P<0 .0 1) ,CD45 RA 均明显下降 ,但两组差异无显著性 (P>0 .0 5 ) ,CD34 无明显改变。 2、经抗 CD3m c Ab γIL- 2激活的 MNC,细胞集落增加 ,但 γIL- 2组无此作用。 3、细胞因子的改变 ,无论经 γIL- 2还是抗 CD3m c Ab γIL- 2激活的脐血 MNC上清液 ,其 IL- 6增高 ,但差异无显著性 (P>0 .0 5 ) ,TNF- α,IL- 8亦明显增高 ,但抗 CD3m c Ab组 >γIL- 2组 (P<0 .0 1)。结论 :脐血抗 CD3激活的杀伤细胞 (CD3AK)比 γIL- 2激活的L AK毒性作用更强 ,更有利于杀伤肿瘤细胞。 相似文献
64.
目的 探讨臀位新生儿窒息、围产儿死亡的相关因素。方法 回顾分析477例单胎初产臀位新生儿Apgar评分与孕周、体重、先露类型、分娩方式的关系。结果 臀位早产儿、过期儿、体重〈2kg及阴道分娩的臀位新生儿容易发生窒息(P〈0.005,P〈0.01)。体重≥2000g4组间Apgar评分较无显著性差异(P〉0.05)。结论 臀位选择 在37~41^+6孕周,估计新生儿体重≥2000g时分娩较合适;及早发现足先露、 相似文献
65.
Vineet Relhan Rima R. Sahay Anita M. Shete Pragya D. Yadav Bijaylaxmi Sahoo Deepak Y. Patil Suresh Kumar Kannan Sabarinath Premachandran Syamaladevi Lalit Dar Sreelekshmy Mohandas Priya Abraham 《Journal of medical virology》2023,95(1):e28249
We describe the clinical and demographic characteristics, virological follow-up, and management of five confirmed monkeypox cases from New Delhi, India without any international travel history. The viral load kinetics and viral clearance were estimated in oropharyngeal swabs (OPS), nasopharyngeal swabs (NPS), EDTA blood, serum, urine, and various lesion specimens on every fourth day of follow-up ranging from 5 to 24 post onset day (POD) of illness. All five cases presented with mild to moderate-grade intermittent fever, myalgia, and lesions on the genitals, groins, lower limb, trunk, and upper limb. Four cases had non-tender firm lymphadenopathy. No secondary complications or sexually transmitted infections were recorded in these cases except for the presence of viral hepatitis B infection marker hepatitis B virus surface antigen (HBsAg) in one case. All the cases were mild and had a good recovery. A higher viral load was detected in lesion fluid (POD 9), followed by lesion roof (POD 9), urine (POD 5), lesion base (POD 5), and OPS/NPS (POD 5). The monkeypox virus (MPXV) DNA was detected in clinical samples from 5th to 24th POD. These monkeypox cases without international travel history suggest the underdiagnosed monkeypox infection in the community. This emphasizes the need for active surveillance of MPXV in the high-risk population such as men having sex with men and female sex workers. 相似文献
66.
67.
Stachowski J.; Pollok M.; Barth C.; Maciejewski J.; Baldamus C. A. 《Nephrology, dialysis, transplantation》1994,9(2):144-152
The study was undertaken to evaluate the relationship betweennon-responsiveness to hepatitis B (HBV) vaccination in haemodialysedpatients and HBs antigen (Ag) presentation and recognition dependingon TCR/CD3 receptors expression. We have found that the causeof the blunted response to HBV vaccination is multifactorialand seems to be associated with the following: (1) A reducednumber of TCR/CD3 antigen receptor complexes on freshly isolateduraemic CD4 T cells, especially in non-responders. (2) The bluntedproliferative response of uraemic CD4 T cells isolated fromnon-responders and stimulated for 6 days by autologous monocytespresenting HBsAg was associated with the decreased density ofthe TCR/CD3 receptors. (3) Moreover, in uraemic non-respondersthe expression of adhesion and accessory molecules on monocytes(intercellular adhesion molecule-1/ ICAM-1, HLA-DR/Ia/) wassignificantly decreased following the culture with autologousmonocytes serving as HBsAg-presenting cells. CD4 molecules andlymphocyte function antigen-1ß /LFA-1ß/on helper-inducer T cells were increased before and after theculture. (4) These findings were also associated with a diminishedbinding capacity of IL-1ß and IL-6 to their receptorson helper-inducer T cells. (5) IL-2, IFN- and IL-4 productionwas decreased in uraemic non-responders, especially after 72h of the culture. (6) Inhibited proliferation of helper-inducerT cells in uraemic non-responders was only partially reversiblein the presence of exogenous IL-1ß, IL-6, IL-2 andIFN-. (7) HLA typing of uraemic non-responders was associatedwith extended haplotype: HLA A1, B8, DR3, DR7, DQ2. 相似文献
68.
用绵羊红细胞(SRBC)免疫小鼠,取其脾脏分离树突状细胞(dendriticcellsDCs)将这些带有抗原信息的DCs经尾静脉注射给小鼠.以观察DCs过继转移抗原的作用。结果表明,各试验组小鼠抗体形成细胞(AFC)及血清中SRBC处价明显高于对照组,P<0.01,再次免疫DC组抗SRBC放价高于初次免疫DC组P<0.05,提示:DCs具有过继转移抗原的作用。 相似文献
69.
腭裂术后语音的实验研究 总被引:2,自引:0,他引:2
王瑛 《天津医科大学学报》1999,5(2):63-66
提供一种易被患者接受、无害、科学客观的腭裂术后语音缺陷的诊断方法。方法:随机选择各种腭裂类型的腭裂术后患者47例,将其语音输入KAY7800语图仪,分析其语音特点和语图表现。结果:腭裂术后语音有3大语音特点和8类语图表现。3大语音特点是残缺、代偿和干扰;8类语图表现是辅音残缺、共振峰残缺、送气代偿、浊化代偿、喉塞代偿、鼻音干扰元音、鼻音干扰辅音和噪音干扰。结论:腭裂术后患者口腔内的能量不足是造成以上语音缺陷的主要原因。 相似文献
70.
Grech V 《European journal of epidemiology》1999,15(10):881-887
Differing pathological haemodynamics in cardiac malformations lead to varying modes and timings of presentation. This study identifies historical trends in presentation of congenital heart disease in a population-based study. All patients diagnosed as having congenital heart disease in Malta between 1960–1994 were included (n = 868). Analysis was carried out on trends in referral sources, modes of presentation and birth prevalence. The number of patients diagnosed with congenital heart disease increased over the period under study. For both patients not requiring intervention (n = 283) and those requiring intervention (n=585), the proportion diagnosed prior to hospital discharge increased (p 0.005). There was a decreasing trend for general practitioners to refer cases (p < 0.0001), and an increasing trend for paediatricians to refer such patients (p 0.0003). The commonest presentation to the general practitioner was an incidental finding (92%), while paediatricians referred more patients for cyanosis or heart failure (p 0.005). For lesions not requiring intervention, the commonest lesion referred was ventricular septal defect from all sources. For lesions requiring intervention, the commonest lesion detected prior to hospital discharge was tetralogy of Fallot. Atrial septal defects were the commonest lesions detected after discharge by both paediatricians and general practitioners. An increase in the proportion of hospital diagnoses is attributed to increasing rate of hospital delivery, and greater training and experience in doctors performing neonatal examinations prior to discharge. Patients diagnosed after discharge are increasingly diagnosed by paediatricians due to an increasing pool of paediatricians and better parent awareness and education. 相似文献