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941.
大鼠肝抑素纯化及其生物活性的检测   总被引:3,自引:1,他引:3  
孙亚平  刘银坤 《解剖学报》1994,25(3):308-312,T015
用SephadecG-5凝胶过滤层析法,进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品,以分离的大鼠再生肝的肝细胞为靶细胞,体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明,E峰浓缩物的抑制作用最强,其活性比为粗提品的20倍,SDS聚丙烯酰胺电泳图及蛋白质迁移率测定表明,该浓缩物的主要成分为分子量13.5kD的多肽。本研究对大鼠肝抑素做了初步纯化,验证了该物质在肝再生中起重要调控作用的生物效应。  相似文献   
942.
本文报道了一种实体组织用于DesoxyribonucleicAcid(DNA)分析的Flowcy tometry(FCM) )样品保存新方法 ,即新鲜组织块乙醇直接固定法。所用样品为头颈部肿瘤手术切除的新鲜标本 3 0例 ,每例标本重约 0 5~ 1 g ,均等分为两份 ,1份置 70 %乙醇直接固定 ,室温放置 ,待两年后FCM检测。另一份置生理盐水中立即行流式细胞术DNA分析。两组样品经机械法制成单细胞悬液 ,PI染色后上机检测。结果显示 :从两组样品的DNA直方图分析 ,CV(coefficiencyofvariation)值、GO/G1、S及G2 /M各期比率无显著差异 (P >0 0 5)。我们认为在样品收集短期内难以完成 ,需积累保存 ,或需保存半年以上者 ,且不具备低温冷冻设备的条件下 ,新鲜组织块乙醇直接固定法是优于将组织块先制备成单细胞悬液再行乙醇固定的流式细胞术DNA样品保存方法  相似文献   
943.
目的观察心理健康对精神分裂症患者认知功能的影响。方法采用入院顺序分层随机法,将120例慢性精神分裂症患者分为研究组(心理健康+奋乃静)和对照组(单用奋乃静)治疗。在治疗前,治疗后4、8、12周末分别以阳性症状和阴性症状量表(PNASS?评定疗效,用韦氏成人智力量表(WAIS—R)、韦氏记忆量表(WMS)和威斯康星卡片分类测验(wCST)评定治疗前后患者认知功能的改变。结果治疗12周后,研究组的言语量表、操作量表、全量表和记忆量表分分别为84.97±3.73、80.41±5.93、83.37±5.81、77.26±13.31;对照组分别为75.41±3.95、72.43±5.56、75.87±5.34、72.15±13.19,两组有显著差异(P〈0.01)。PANSS总分、阴性因子分比治疗前明显降低。结论心理健康治疗对精神分裂症患者认知功能有明显改善。  相似文献   
944.
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer.  相似文献   
945.
淋巴细胞经TCR-CD3活化增殖作用的分析   总被引:1,自引:0,他引:1  
本文探讨了抗CD3单抗诱导的淋巴细胞活化增殖及有关影响因素。实验结果表明:①淋巴细胞内钙升高是淋巴细胞活化增殖的重要条件,CD3McAb引起的早期胞浆游离钙迅速升高主要由内质网释放钙离子所致,而淋巴细胞增殖不仅需要细胞内钙释放,还需要细胞外钙内流;②GTP结合蛋白是淋巴细胞激活过程的一重要环节,经G蛋白作用物霍乱毒素作用后,淋巴细胞DNA合成显著降低;③新霉素和PSS可抑制PLC和PkC的活性,对淋巴细胞NDA合成造成剂量依赖性抑制作用。此外,抗CD3McAb诱导的淋巴细胞DNA合成需要辅佐细胞的存在,高度纯化的T细胞对CD3McAb的刺激不发生增殖反应。  相似文献   
946.
Heme is a non-protein autoantigen which is ubiquitous in vivo, primarily complexed in various hemoproteins or bound to specialized carrier molecules. Nevertheless, heme is able to stimulate a high frequency of CD4+, class II-restricted T cells, freshly explanted from unprimed mice, to proliferate in vitro. In this study, we show that heme incorporated into various species of mammalian cytochrome c (cyt c), including murine cyt c, represents a facultative cryptic determinant, able to be recalled only at high doses of native cyt c. By contrast, avian cyt c is of comparable antigenicity to free heme. Artificially denatured carboxymethylated (CM) mammalian cyt c exhibited greatly increased antigenicity, comparable to that of heme and avian cyt c, indicating that the crypticity of heme in native mammalian cyt c is due to the resistance of the native conformation of this molecule to antigen processing within murine antigen-presenting cells. Thus, tolerance to the heme group of at least some hemoproteins, may be maintained by the crypticity of the heme, rather than by deletion of hemereactive T cells. Given the high frequency of heme-reactive T cells in unprimed mice, these findings suggest that heme may become an important modulator during an inflammatory response.  相似文献   
947.
本文报告了应用三种不同类型杀虫剂DDVP,残杀成和溴江菊酯点滴处理敏感株德国小蠊(Blattellagermanica)不同虫期后的药物敏感性以及带荚虫脱荚及其孵化情况。试验得出了不同虫期不同时间的LD50植和72h不同虫期对这3种药物敏感性的显著性测定(P值)的结果。发现不同虫期对这3种药物的敏感性之间关系的共同特点是:1.幼虫与雄虫敏感性差别显著(在DDVP和残杀威中)或者非常显著(在溴氰菊酯);2.雌虫与雄虫间差别在3种药物处理中均显著;3.雌虫与带荚虫在DDVP和溴氰菊酯处理中差别也非常显著。试验同时显示,3种药物不同浓度处理对德国小蠊脱荚及其孵化有十分显著的影响。其总的趋势是随着药物浓度的增高脱荚率明显地增加;相反,脱荚的孵化率则随着浓度的增加明显的下降。实验并得出脱荚的孵化与否和卵荚长度无明显关系。  相似文献   
948.
This is a cohort study of pediatric outpatients receiving total parenteral nutrition (TPN) and follow-up care in a Tennessee hospital between January and June 1999. The study was conducted following an increase in the incidence of candidemia. Of 13 children receiving home TPN, five had candidemia; three were due to Candida parapsilosis. Case patients were more likely to have an underlying hematologic disease (P = 0.02) as well as previous history of fungemia (P = 0.02). Two case patients had successive candidemia episodes 3 months apart; karyotypes and RAPD profiles of each patient's successive C. parapsilosis isolates were similar. Candida spp. were frequently detected in hand cultures from cohort members (four of 10) and family member caregivers (nine of 11); C parapsilosis was isolated from five caregivers. Our findings underscore the challenges of maintaining stringent infection control practices in the home health care setting and suggest the need for more intensive follow-up and coordination of home TPN therapy among pediatric patients.  相似文献   
949.
蛋白转导域介导BCR/ABL抗原对CML患者T细胞的活化作用   总被引:2,自引:0,他引:2  
目的:研究蛋白转导域(PTD)介导的BCR/ABL抗原对慢性髓细胞白血病(CML)患者T细胞的特异性活化作用。方法:利用基因工程技术,将PTD基因与CML b3a2 bcr/abl基因融合并原核表达。将纯化的PTD—BCR/ABL融合蛋白与CML患者外周血单个核细胞(PBMC)体外共孵育,用流式细胞仪分别检测CD4^ 、CD8^ T细胞上活化抗原CD25的表达。结果:终浓度为100mg/L的PTD—BCR/ABL抗原体外刺激4d后,10例CML患者中,5例表现为CD8^ T细胞活化,2例表现为CD4^ T细胞活化,其中有1例CD8^ 和CD4^ T细胞同时活化;而作为对照的BCR/ABL抗原刺激组无一例表现为CD8^ 或CD4^ T细胞活化。结论:PTD能将外源性BCR/ABL抗原转导入抗原呈递细胞内,加工呈递后激活抗原特异性CD8^ 及CD4^ T细胞,为CML特异性CD8^ 、CD4^ T细胞的体外活化及细胞免疫治疗开辟一条新的途径。  相似文献   
950.
BACKGROUND: Laparoscopic bipolar coagulation of uterine vessels (LBCUV) has been employed for women with symptomatic uterine myomas, but its effect on subsequent pregnancy has not been characterized. METHODS: Four-hundred and twenty-three women entered the study between March 1999 and December 2001. Of these, 142 women (33.6%) were under the age of 40 years at the time of LBCUV, 36 of whom (36/142, 25.3%) were sexually active without contraception. In a prospective study of 142 patients (<40 years old) undergoing LBCUV for symptomatic myomas, 15 women became pregnant (17 total pregnancies) and were evaluated by physical and ultrasound examinations. RESULTS: The volume of the dominant myoma was 117.4 +/- 118.4 and 36.8 +/- 56.8 cm(3) before and after LBCUV respectively. Volume of the dominant myoma after pregnancy was 46.2 +/- 76.7 cm(3) (mean +/- SD). There was a significant difference in myoma volume before and after LBCUV (P = 0.002), but no significant difference in myoma volume when comparing post-partum size with post-LBCUV size (P = 0.269). Pregnancy outcomes included seven miscarriages in the first trimester and one premature rupture of membrane (PPROM). Although the other pregnancies were regarded as uncomplicated, only two women were delivered of normal neonates as the other seven pregnancies were terminated secondary to patient request. CONCLUSIONS: The pregnancy and term pregnancy rates in sexually active women without contraception were 41.6% (15/36) and 5.6% (2/36) respectively. Because a relatively high rate (7/17, 41.2%) of early miscarriages was observed, we recommend that this procedure be employed only for women who do not desire additional children.  相似文献   
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