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991.
At embryo implantation we are confronted with the fact that uterine and trophoblast epithelium make contact via their apical cell membranes. This epithelium-epithelium adhesion leading to definitive attachment of the embryo to the uterine wall, however, is far from being trivial and has been called a cell biological paradox. It has been proposed that some of the molecular events involved in epithelium-to-mesenchyme transformation might play a role in the interaction between uterine cells and trophoblast. As a mechanism to achieve uterine epithelium adhesiveness for trophoblast it is postulated that uterine cells partially modulate their epithelial phenotype. Data from recent in vitro experiments give support to this hypothesis and suggest that loss of apical-basal cell polarity might prepare the apical cell pole of uterine epithelium for cell-to-cell contact with trophoblast in vivo. 相似文献
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RS Veazey DW Horohov JL Krahenbuhl HW Taylor JL Oliver TG Snider 《Canadian Metallurgical Quarterly》1996,19(4):289-304
The accumulation of various T cell subsets in Bcg-susceptible (C57BL/6) and- resistant (C3H/HeN) strains of mice were compared following an intraperitoneal infection with Mycobacterium paratuberculosis. Groups of mice from both strains were killed at 3, 5, 10, 15, 30, and 150 days after infection and lymphocytes were harvested from the peritoneal exudate cells (PEC), spleen, intestinal epithelial lymphocytes (IEL), lamina propria lymphocytes (LPL), Peyer's patches, and mesenteric lymph node (MLN) and labelled with monoclonal antibodies to CD3, CD4, CD8, gamma delta TCR, CD25, and CD44 for flow cytometric analysis. Uninfected C3H/HeN mice had higher proportions of CD4+ cells in the spleen, MLN, LPL, IEL, and Peyer's patches, while uninfected C57BL/6 mice had higher proportions of CD8+ and/or gamma delta T cells. Significant increases in accumulation of CD8+ and gamma delta T cells were detected in the peritoneum and other tissues in both strains of mice after infection. Higher CD4/CD8 ratios were observed in most lymphoid tissues of C3H/HeN mice, while increased proportions of CD8+ and/or gamma delta T cells were present in C57BL/6 mice. These results indicate that significant differences in T cell profiles exist between these two strains of mice, both inherently and in response to infection with M. paratuberculosis. Innately lower levels of CD4+ cells and/or higher percentages of CD8+ and gamma delta T cells may play a role in the increased suspectibility of C57BL/6 mice to infection with M. paratuberculosis. 相似文献
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We studied physical fitness and physical activity in relation to all-cause and cancer mortality in a cohort of 7080 women and 25,341 men examined at the Cooper Clinic in Dallas, Texas, during 1970 to 1989. Physical fitness was assessed at baseline by a maximal treadmill exercise test, while physical activity was self-reported on the attendant health habits questionnaire. Both men and women averaged about 43 years of age at baseline (range, 20 to 88 years), and they were followed for approximately 8 years on average. Through the end of 1989, the women contributed 52,982 person-years of observation and incurred 89 deaths, including 44 deaths due to cancer. The men contributed 211,996 person-years and incurred 601 deaths, with 179 due to cancer. After adjustment for baseline differences in age, examination year, cigarette habit, chronic illnesses, and electrocardiogram abnormalities, we found a strong inverse association between risk of all-cause mortality and level of physical fitness in both men and women (P for trend < 0.001). Physically active men also were at lower risk of all-cause mortality than were sedentary ones (P for trend = 0.01). Among women, however, self-reported physical activity was not significantly related to risk of death from all causes. The risk of mortality from cancer declined sharply across increasing levels of fitness among men (P for trend < 0.001), whereas among women the gradient was suggestive but not significant (P for trend = 0.07). Physically active men also were at lower risk of death from cancer than were sedentary men (P for trend = 0.002), but among women physical activity was unrelated to cancer mortality. 相似文献
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We present the Graph Layout module of the ILOG J Views Component Suite, which is a set of pure Java components for building sophisticated interactive commercial graph-based user interfaces. 相似文献
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OBJECTIVE: To describe the clinical characteristics and risk of progression of asymptomatic rhegmatogenous retinal detachments. METHODS: We retrospectively reviewed the clinical records of 28 patients (31 eyes) with asymptomatic rhegmatogenous retinal detachments followed up without surgery for 0.5 to 12.1 years (mean, 3.4 years). Tractional tears were present in six eyes and atrophic holes in 25 eyes. In five patients, the asymptomatic retinal detachment was noted when the patient presented with a symptomatic retinal detachment in the fellow eye. RESULTS: Twenty-nine of the 31 eyes remained asymptomatic without progression of the retinal detachment. Two eyes progressed to a symptomatic retinal detachment 2.25 and 3.3 years after the initial examination, underwent a successful scleral buckling procedure, and maintained 20/20 visual acuity. CONCLUSIONS: Observation can be considered a reasonable option in the treatment of patients with asymptomatic retinal detachments. Chart documentation of the risks and benefits of observation and instruction of the patient on self-monitoring of the peripheral visual field are necessary in such patients. 相似文献
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Since 1969, we have used 2 different types of knee prostheses to reconstruct arthritic knees. The surface replacement prosthesis (sledge) is indicated where ligamentous stability is present and angular deformity is not severe. In addition, the sledge prosthesis may be implanted with good results in selected acute comminuted tibial plateau fractures. The total hinged prosthesis of metal design is recommended in knees which are severely deformed, and unstable, and therefore not suitable for the sledge prosthesis. Marked relief of pain was the most significant result in our patients. Residual knee pain was most frequently due to patello-femoral pain and, when severe, this was satisfactorily controlled by performing a patellectomy. Motion was usually maintained at the preoperative range or improved, mainly by reducing or eliminating the knee flexion contracture. In a high percentage, the unicompartmental sledge prosthesis has given excellent results. However, we tend to insert a bi-compartmental sledge prosthesis because experience has shown that even slight damage of the articular surfaces of the opposite side is likely to further deteriorate rapidly. Although a significant number of complications occurred, these have been minimized by further conservative and operative treatment. We anticipate a further reduction in complications based on our initial experience, and prosthetic revisions. 相似文献