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51.
 目的 构建携带 eap 基因的原核表达载体,诱导表达具有活性的重组 EAP 融合蛋白。 方法 PCR 法扩增金黄色葡萄球菌基因组 DNA,回收、 纯化的扩增产物与 pMD18-T 载体相连接得重组质粒 pMD18-T-EAP,转化 E.coli BL21(DE3)感受态细胞,酶切鉴定;未酶切组作为对照组重组质粒 pMD18-T-EAP 和 pET28a(+)表达载体分别用 Nde I 和 Xho I 限制性内切酶双酶切、连接,转化 E.coli BL21(DE3)感受态细胞,酶切鉴定;空载体作为对照组。用不同浓度(终浓度 1、2、4、8 mmol/L)和不同诱导时间(1、2、3、4、5、6 h)的异丙基-β-D-硫代半乳糖苷(IPTG)对阳性重组菌进行表达优化,分别取 E.coli上清液和沉淀做电泳分析。应用 MagneHisTM 蛋白纯化系统纯化重组 EAP 融合蛋白,并通过薄层扫描测定蛋白质的浓度。 结果 所获 eap 基因与 GeneBank 的基因序列同源性 > 99%;氨基酸同源性达 100%。重组质粒经 IPTG 诱导,阳性重组菌转化子均有表达;当吸光度(A )值等于 0.6 ~ 0.8 时,相对分子质量约 70 000 处出现目的蛋白条带。破碎的重组菌 pET28a-EAP上清液中目的蛋白条带较清楚,沉淀中几乎看不到。终浓度 1 mmol/L 为最佳蛋白表达工作浓度。IPTG 诱导 1 h 重组 EAP 融合蛋白有一定量的表达,随着时间的延长,表达量增加不明显,3 h 时的表达量达最高,之后,蛋白表达量变化不明显。表达的重组 EAP 融合蛋白含量占全菌体蛋白的 29.6%。 结论 成功地克隆和表达了金黄色葡萄球菌重组 EAP 融合蛋白,为进一步研究以 EAP 蛋白作为免疫原预防和治疗由金黄色葡萄球菌引起的疾病奠定基础。  相似文献   
52.
输精管结扎家兔自身免疫反应的实验研究   总被引:3,自引:0,他引:3  
33只成年雄兔行双侧输精管结扎手术后,进行连续12个月的免疫学观察。7只同龄雄兔作为空白对照。结果表明,间接血凝试验69.7%结扎组家兔检测出抗精子抗体,滴度范围为1:5~1:1280;间接免疫荧光测定有90.9%的实验组家兔测出抗精子抗体。白细胞粘附抑制实验呈阳性反应者占实验组家兔的43.5%,与对照组比较差异显著。应用PEG光密度和抗补体法测定CIC均里阴性。输精管结扎后第3个月附睾肿胀者占45%,第5—7个月达70%,之后逐渐消退。而与此同时抗精子抗体阳性检出率明显增高,故可推断精子抗原主要经附睾入血,作用于免疫系统导致体液与细胞免疫反应。结扎组家兔胸腺、脾、淋巴结呈明显的增生现象支持这一结论。  相似文献   
53.
Perepletchikova and Kazdin's (this issue) analysis of the treatment integrity literature should guide future research and practice on this vital issue facing clinical research and practice. This commentary considers the construct of treatment integrity and those factors that moderate the relationship between treatment integrity and treatment outcome. Specifically, this paper examines the three components of treatment integrity specified by Perepletchikova and Kazdin (treatment adherence, therapist competence, treatment differentiation), the relationship between treatment integrity and treatment outcome, and measurement and validation issues involving treatment integrity.  相似文献   
54.
Enterotoxigenic Escherichia coli strains expressing F17 fimbriae bind to the intestinal mucosa of young calves. F17 fimbriae recognize receptors present in the mucus layer and the brush-border membranes from duodenum, jejunum and ileum. The adhesion of E. coli F17 can be inhibited by several glycoproteins. Adhesion is also inhibited by pretreatment of mucus and brush-border membranes with sodium metaperiodate. The use of glycoconjugates as potential adhesion-blockers is further discussed.  相似文献   
55.
Investigated the behaviors of pediatric rheumatology healthcare providers that were expected to be related to patient orparent adherence. Medical charts of 108 patients ages 1 to 20years diagnosed with Juvenile Rheumatoid Arthritis were examined.The 473 outpatient visits over 15 months yielded a total of2,578 treatment recommendations, but only 1,390 adherence-facilitatingbehaviors by medical staff were documented. Providing informationabout how often to perform the recommendation was the most commonstaff behavior. In contrast, care providers rarely indicatedthat they addressed their patients' concerns and barriers toimplementing the recommendations, or employed behavior modificationstrategies to increase adherence. Implications of these findingsfor development of programs designed to increase treatment adherencein children with chronic diseases requiring time-consuming,intrusive medical regimens are discussed.  相似文献   
56.
本文报道了30例食管癌、20例胃癌、15例乳腺癌、8例肝癌、10例淋巴瘤等患者红细胞免疫粘附功能的初步结果,并与67例献血员值进行了比较。几种肿瘤病人的RBC C_(3b)RR低下,RBC-ICR较高,两者与献血员值比较都有明显差别(P<0.01),几种肿瘤患者CIC阳性率在60~83.4%之间。对食管癌患者部分病例进行跟踪检测,并对其临床意义进行了初步探讨。  相似文献   
57.
精神专科医院门诊抑郁症患者服药依从性影响因素分析   总被引:5,自引:0,他引:5  
目的:探讨影响抑郁症患者服药依从性的影响因素.方法:选取2007年5月至10月于北京大学第六医院及北京回龙观医院门诊就诊的123例抑郁症患者,采用自编抑郁症患者就诊状况及服药依从性调查问卷进行调查,内容包括患者一般情况、患病及就诊情况调查、抑郁症发病次数、巩固治疗期坚持服药时间知晓情况及实际服药情况等.分别采用卡方检验及多元Logistic回归分析,探讨上述各因素与服药依从性的相关性.结果:完全依从组(完全按照医嘱时间和剂量服药的患者)和部分依从组(部分按照医嘱时间和剂量服药的患者)在医疗费用支付形式、病程、家属态度、抑郁症阳性家族史、对疾病性质的认识、就诊模式、第一主诉、患病次数、坚持服药时间知晓情况、家庭平均月收入等方面的差异有统计学意义(P<0.05),将患者服药依从情况作为因变量,将以上项目作为自变量进行Logistic回归,结果显示月收入、对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程进入回归方程,各变量比值比分别为:10.932、9.604、7.246、6.019、2.611、0.209.结论:抑郁症患者服药依从性与多方面因素相关,对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程、家庭平均月收入等是影响抑郁症患者服药依从性的重要因素.  相似文献   
58.
Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts to diminish biomaterial-related infections.  相似文献   
59.
ABSTRACT: Leukocyte adherence inhibition (LAI) assay was used to evaluate cell-mediated immunity in patients with invasive squamous cell carcinoma of the cervix. The reactivity of the peripheral blood leukocytes of these patients was evaluated after incubation with pooled extracts of allogeneic squamous cell carcinoma of the cervix. One hundred sixty-seven sets of LAI assays were performed on 54 individuals, including 23 patients with Stage I squamous cell carcinoma of the cervix, 9 patients with other stages of this tumor, 9 patients with unrelated tumors and 13 normal healthy volunteers. A protein concentration of one milligram per milliliter in the tumor extract and 10% fetal bovine serum in the feeding media gave the best results. Eighty-seven percent (28/32) of patients with squamous cell carcinoma of the cervix showed marked specific reactivity. No difference was found in the LAI indices of different stages of the disease.  相似文献   
60.
This cross‐sectional study identified variables associated with protease inhibitor (PI) non‐adherence in 179 patients taking anti‐retroviral therapy. Univariate analyses identified 11 variables associated with PI non‐adherence. Multiple logistic regression modelling identified three predictors of PI non‐adherence: low adherence self‐efficacy and seriousness of non‐adherence and HIV (p < .001), perceived absence of HIV associated illness (p < .01), and use of more than one type of recreational drug (p = .001). The model correctly classified 83.9% of the sample, offers psychologists insight into psychological barriers to treatment adherence to guide interventions for improving adherence, and supports a modified version of the reformulated health belief model.  相似文献   
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