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The relative contributions of T-lymphocyte subsets to host defense in cattle infected with Mycobacterium avium subsp. paratuberculosis is reported. The subsets were purified with appropriate monoclonal antibodies and a magnetic bead column separation system, and their purity was verified by flow cytometry. Biological activity of each subset, expressed as lymphoproliferation and gamma interferon (IFN-gamma) production, was measured in response to phytohemagglutinin (PHA) and an M. avium antigen preparation (A-PPD). IFN-gamma was measured by antibody capture enzyme-linked immunosorbent assay. The results showed a correlation between proliferation and IFN-gamma production in response to A-PPD but not to PHA. In response to PHA, CD4+ lymphocytes were the most prolific producers of IFN-gamma. CD8+ lymphocytes produced IFN-gamma to a lesser extent, whereas gammadelta+ T lymphocytes produced little or no IFN-gamma. Differences observed between the amount of IFN-gamma produced by CD4+ versus CD8+ cells and CD4+ versus gammadelta+ cells were significant (P < 0.01), but those between peripheral blood mononuclear cells (PBMC) and CD4+ T cells were not. Similar responses to A-PPD were observed except that PBMC produced higher levels of IFN-gamma than did CD4+ T cells. These data for cattle are similar to observations made for other animal species, where CD4+ cells are the major type of T lymphocytes producing IFN-gamma. They further suggest that whatever the role gammadelta+ T cells may play in paratuberculosis, it is not likely to be mediated by IFN-gamma production.  相似文献   
3.
目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础.  相似文献   
4.
BACKGROUND: Reduced levels of physical activity have been found to be associated with an increased risk of osteoporotic fracture in a number of epidemiological studies, and intervention studies have shown beneficial effects of exercise regimes on bone mineral density. It is not yet established, however, which specific forms of customary physical activity are most strongly associated with bone mineral density in postmenopausal women. METHODS: A cross-sectional study was conducted in 580 postmenopausal women, aged 45-61 years, resident in Nottingham, England. The participants completed a detailed interviewer-administered activity questionnaire. Physical activity was assessed as total hours of participation per week in activities including housework, walking, gardening and sports. Stair-climbing and self-reported walking pace were also reported. Bone mineral density measurements were made using dual energy x-ray absorptiometry, measurements at five sites were used in analysis. RESULTS: The strongest associations between the activity measures and bone mineral density were for stair-climbing and walking pace, which both gave statistically significant positive associations at the trochanter hip site and the whole body. In women reporting a fairly brisk or fast walking pace, bone mineral density at the proximal femur was also significantly and positively associated with the frequency of walking at least a mile. There were no significant associations with aggregate measures of total customary physical activity. CONCLUSIONS: This study has identified two forms of physical activity, namely stair-climbing and brisk walking which are associated with increased bone mineral density at the hip and whole body in postmenopausal women. Both are feasible forms of activity for promoting to middle-aged women.  相似文献   
5.
Hendrix  SL  Cochrane  BB  Nygaard  IE  沈平虎 《英国医学杂志》2006,9(1):48-49
问题:在绝经后健康妇女中,激素治疗(hormone therapy,HT)对尿失禁(urinary incontinence,UI)的效果如何?  相似文献   
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7.

Background

The containment of poliovirus infectious/potentially infectious materials in all biomedical facilities in Nigeria remain crucial to maintaining gains recorded towards polio eradication. Activities involved in the Nigerian Poliovirus type 2-laboratory containment survey in line with the 3rd Global Action Plan III (GAP III) for poliovirus containment are documented in this study. Through these activities, the overall preparedness for poliovirus eradication in Nigeria is assessed.

Method

A cross-sectional survey was conducted from 19th September-31st October 2016 using structured Laboratory survey and inventory (LSI) questionnaires uploaded onto the SPSS software package in 560 biomedical facilities classified either as high risk or medium risk facilities across the 6 zones in Nigeria.

Results

In total, 560 biomedical facilities were surveyed in Nigeria in conformity with the GAP III. In total, 86% of the facilities surveyed were with laboratories while 14% were without laboratories.Twelve laboratories with poliovirus potentially infectious materials were identified in this exercise. In total, 50% of the 12 laboratories were under the ministry of education for research purposes. While 33% were among those laboratories surveyed in the phase 1a exercise without any recorded inventory, but have acquired some since the phase 1a survey.A total of 13,484 poliovirus infectious materials were found in the 12 laboratories. Only 8% of the materials were immediately destroyed while the remaining materials (62%) were found in Oyo and Borno states scheduled for destruction within 3–4 months according to WHO protocol for destruction of poliovirus infectious materials.

Conclusion

This study has revealed the successful containment of all poliovirus infectious materials in the laboratories surveyed. It has also revealed some surveillance gaps. We recommend that the surveillance system be improved to maintain the gains from the containment exercise and avoid reintroduction of infectious materials into biomedical facilities. This reduces the chances of viral reintroduction to the population in general.
  相似文献   
8.
 目的:探讨上皮样血管瘤(EH)的临床及组织病理学特征。 方法:回顾性分析16例已确诊患者的临床及病理资料,并对相关文献进行综述。 结果:16例患者中女8例,男8例;平均年龄(45.44±12.52)岁;病程3个月~20年;皮损主要表现为红色至暗红色丘疹、结节,可伴瘙痒和糜烂,好发于头皮、耳部,其中发生在头部10例、耳部5例、外阴1例;皮损单发者5例,多发者11例。皮损组织病理学检查均具有典型的血管增生,管壁增厚,内皮细胞呈上皮样突向管腔,管周大量淋巴细胞及嗜酸性粒细胞浸润。结论:上皮样血管瘤少见,诊断需要临床与病理密切结合。加强对该病的认识,可避免误诊误治。  相似文献   
9.
ObjectiveBody mass index (BMI), uric acid, diabetes mellitus, and hypertension are risk factors for reduced kidney function and are associated with fetuin-A levels, but their causal pathways remain unclear. The objective of this study was to investigate this knowledge gap.MethodsA repeated cross-sectional design was used to assess causal pathway effects of fetuin-A on the estimated glomerular filtration rate (eGFR), which is mediated through BMI, uric acid, diabetes mellitus, and hypertension.ResultsAmong 2305 participants, the mean eGFR at baseline decreased from 98.7 ± 23.6 mL/minute/1.73 m2 in 2009 to 92.4 ± 22.9 mL/minute/1.73 m2 in 2014. Fetuin-A was significantly associated with eGFR , suggesting that increasing fetuin-A levels predict a decrease in eGFR. Additionally, the indirect effect of fetuin-A on eGFR, as assessed through BMI, was also significant. The effects of fetuin-A on eGFR through other mediation pathways showed variable results.ConclusionsOur study revealed a possible role of fetuin-A in the etiology of declining renal function through mediating body mass index, uric acid, diabetes mellitus, and hypertension via complex causal pathways. Further studies to clarify these mediated effects are recommended.  相似文献   
10.
We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs.  相似文献   
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