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Interferon-, interferon-, and interferon- differ in their antiproliferative effects for several cell lines. Interferons were thus assessed for their activity in inhibiting proliferation of three renal cell carcinoma cell lines. The malignant epithelial phenotype of each of these cell lines was confirmed by electron microscopy, histology, karyotype and tumorigenicity. When compared on an anti-viral unit basis, naturally produced interferon- was more effective than natural interferon- for all cell lines and clones. Proliferation of each of the cell lines was inhibited by interferon-. In all cases, removal of interferons from culture media resulted in resumption of the rate of cell growth after a variable delay of 6–10 days. If the antiproliferative effects of interferons predominate in mediating tumor regression, clinical response may depend upon the type of interferon to which the tumor is exposed.  相似文献   
3.
A monoclonal antibody has been prepared against rat angiotensin-converting enzyme (ACE). By selection for antibody binding to endothelial cells of bovine rather than rat origin we have obtained a reagent that has broad cross-species binding properties and that can at the same time serve as a useful marker for the surface of endothelial cells. The IgM-producing clone that we have established, alpha-ACE 3.1.1, has been grown in ascites form to yield ascites fluid that binds selectively to immobilized ACE at a greater than 1:10,000 dilution. By use of enzyme-linked immunosorbent assays, immunofluorescence histology, and flow cytometry, we have demonstrated the presence of ACE on endothelial cells of murine, bovine, and human origin. By means of a fluorescence-activated cell sorter (FACS-IV) we have been able to selectively isolate viable endothelial cells from a mixture of endothelial cells and fibroblasts. We believe the antibody will be useful not only for the selection and in vitro cultivation of endothelial cells but also as a tool for the identification and pharmacological study of ACE.  相似文献   
4.
Infection by the intestinal nematode parasite Nematospiroides dubius was studied in seven different inbred mouse strains. Although there was some minor variation in the susceptibility of the different strains to a primary infection there were marked differences in their ability to develop resistance to infection following repeated exposure to infective larvae. The strains of mice which developed the best resistance also expelled adult worms arising from the previous infections. The adult worms resulting from a primary infection were slowly eliminated in two inbred strains studied whereas no loss occurred from outbred LACA mice. Although males and females of two strains, C3H/HeJ and CBA/H were equally susceptible to a primary infection, the females developed better resistance than the male mice following two oral administrations of third stage larvae. Infected mice of every strain and both sexes contained high levels of IgG1 in the serum.  相似文献   
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Background  

Common vaginal infections that manifest in women are usually easily diagnosed. However, Chlamydia infection is often asymptomatic, leading to infertility before it is detected. If it occurs in pregnancy, it could lead to significant neonatal morbidity. It may also play a role with other viral infections for e.g. Human Papilloma Virus in the development of cervical cancer. The objective of this study was to determine the prevalence of Chlamydia infection in women undergoing screening for cervical abnormalities as a part of a research project in primary and secondary care institutions in the United Arab Emirates.  相似文献   
7.
骨骼肌缺血再灌注损伤及发病机制初探   总被引:4,自引:1,他引:3  
张俐  Seaber AV  Urbaniak JR 《中国骨伤》2001,14(11):667-670
目的:探讨骨骼肌缺血再灌注损伤过程的微循环变化。组织学改变以及多肽含量变化和意义。方法:42只雄性大鼠随机分为留伴行神经组和去伴行神经组,建立标准骨骼肌缺血再灌注模型,采用激光多谱勒及显微放大分析系统,组织学方法以及凝胶电泳方法等观察缺血再灌注损伤变化。结果:缺血再灌注损伤后的骨骼肌微血管管径在20分钟时恢复率基本达到高峰约60%,此后为平台期:90分钟最高峰,为75%,主干血管流速率亦在20分钟基本达到上限,病理检查显示:缺血的骨骼肌纤维呈空泡状,核形态增大,染色加深,红细胞严重聚集,凝胶蛋白电泳提示:缺血骨骼肌中分子量20KD左右的多肽显著增加。结论:骨骼肌缺血再灌注损伤发生后,骨骼肌的微循环发生不同程度的破坏,及因之导致骨骼结构损伤和异常的20KD多肽含量明显增加,以及红细胞凝聚,白细胞的改变,这些共同构成了缺血再灌注损伤机制。  相似文献   
8.

Background

Tibial fractures are the most common long bone fracture. The standard of care for the treatment of diaphyseal tibial fractures is an intramedullary nail (IMN). Implant removal is one of the most common procedures in bone and joint surgery, and criteria for implant removal are typically left to the treating surgeon. Currently, no clear criteria exist to guide a surgeon''s decision to remove implanted tibial IMNs after healing.

Methods

We undertook a retrospective chart review of a single surgeon''s practice from January 1996 to February 2005. We identified patients aged 16–70 years with a tibial fracture treated with an IMN. Patients were followed until fracture union and/or request for IMN removal. The following parameters were recorded: reason for implant removal, age, sex, mechanism of fracture, location of fracture, diameter of IMN, Workers'' Compensation Board (WCB) status, activity level, litigation status, insurance involvement, height, weight and body mass index (BMI).

Results

Factors influencing the likelihood of removal were sex and litigation. Factors not influencing the likelihood of removal were age, weight, height, BMI, diameter of IMN, patients'' level of activity, insurance claim involvement and WCB involvement. Overall, 72.2% of patients had an improvement in their symptoms after IMN removal.

Conclusion

Sex and litigation are positive predictive factors for patient requests to have tibial IMNs removed after healing.  相似文献   
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10.
Chlamydia trachomatis infections of the female and male genital tracts are often asymptomatic and, thus, tend to become persistent. In the persistent state the typical Chlamydia life cycle is arrested and standard antibiotic regimens do not always eradicate this infection. We sought to relate treatment failures in men and women with persistent chlamydial genital tract infections to electron microscopic evidence of chlamydial persistence and with atypical morphological forms of the organism. Of 16 patients with chlamydial persistence following azithromycin treatment, morphological variants of this organism were observed by electron microscopy from one endocervical sample and one male urethral sample. We document the presence of intracellular inclusions containing only reticulate bodies, extracellular monomembrane and polymembrane phagosomes containing elementary bodies and reticulate bodies with abnormal outer membranes in the process of dividing extracellularly. These observations parallel previous in vitro studies of chlamydial persistence under adverse conditions. This capacity of C. trachomatis to undergo atypical morphological alterations in vivo may contribute to its persistence and relative resistance to antibiotics.  相似文献   
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