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排序方式: 共有289条查询结果,搜索用时 15 毫秒
1.
自1980年4月至1995年4月,应用碳—钛组合式人工股骨头治疗髋关节疾患319例。随访最短1年,最长15年。随访结果:股骨颈骨折组优良率93%,股骨头无菌性坏死组优良率89.8%。余者2例失败,4例髋关节周围钙化,2例碳质头略大,3例假体下沉,1例类风湿性髋关节强直,术后关节再强直。1例髋臼硬化,4例6髋关节明显疼痛。4例死于心血管疾病。我们体会到碳质材料具有良好的物理、化学性能和生物相容性,是一种优良的人工关节材料。碳—钛组合式人工股骨头是目前优良的人工假体之一。  相似文献   
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ProbCons: Probabilistic consistency-based multiple sequence alignment   总被引:23,自引:4,他引:23  
To study gene evolution across a wide range of organisms, biologists need accurate tools for multiple sequence alignment of protein families. Obtaining accurate alignments, however, is a difficult computational problem because of not only the high computational cost but also the lack of proper objective functions for measuring alignment quality. In this paper, we introduce probabilistic consistency, a novel scoring function for multiple sequence comparisons. We present ProbCons, a practical tool for progressive protein multiple sequence alignment based on probabilistic consistency, and evaluate its performance on several standard alignment benchmark data sets. On the BAliBASE, SABmark, and PREFAB benchmark alignment databases, ProbCons achieves statistically significant improvement over other leading methods while maintaining practical speed. ProbCons is publicly available as a Web resource.  相似文献   
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Duodenal ulcer     
In 1958 the Yale freshman class gave blood samples as part of a study intended to determine the predictive value of plasma pepsinogen (PP) for the subsequent development of duodenal ulcer (DU). We report a long-term follow-up of this cohort. A selfadministered questionnaire designed to ascertain information about the development of peptic ulcers, and the presence of risk factors was mailed to 861 subjects with active addresses. A second questionnaire was mailed to each respondent's physician(s) to verify the diagnosis of DU. Completed questionnaires were returned, after three mailings, by 604 (70%) of the subjects. They reported 18 documented DUs, 15 since 1958, for an incidence of 1.1/1000 person years. Only smoking (P<0.05) and undergraduate physical inactivity (P<0.01) were identified as risk factors for DU. Family history; blood type; blood antigen secretor status; ingestion of coffee, alcohol, milk, salicylates, soda, or tea; and COPD were not identified as risk factors for DU. Patients with DU had higher mean PP values than those who did not (391.6±99.6 vs 346.6±106.7, mean ±sd) but this was not statistically significant (P>0.05). The predictive value of an elevated PP(>450) for the development of DU was 7.9%, but a low or normal PP predicted the absence of a DU in 97.5% of subjects over a 22-year span. We conclude that in a selected population followed for 22 years there is a low incidence of DU, supporting the general belief that duodenal ulcer is declining, that smoking and undergraduate physical inactivity are risk factors for duodenal ulcer, and that a low or normal PP may be useful as a predictor for a low susceptibility to duodenal ulcer disease.Dr. J. Chuong acknowledges the support of the Robert Wood Johnson Clinical Scholar Program, and the Daland Fellowship in Clinical Medicine of the American Philosophical Society.  相似文献   
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This study was designed to investigate the menstrual, psychosexual, psychological and somatic sequelae in a group of women who may be more prone to express regret following sterilisation. They were at a younger age, and all underwent postpartum sterilisation. The follow-up was conducted by a questionnaire between 6 months and 5 years following the procedure. Data were available from 242 patients with 76.8% before age 30, and 23.2% age 30 or older. Of all the patients, 21.9% regretted their choice of sterilisation. About one-third had various menstrual cycle disturbances. In general, patients rated their sex life more enjoyable in many aspects. The two most common psychological symptoms were irritability, nervousness and depression. The common somatic symptoms were pelvic/ abdominal pain, backache and tiredness. A complete assessment of the patient's postoperative condition, including menstrual cycle history, sexual history, psychological and somatic complaints if any, is warranted during presterilisation counselling in addition to a routine informed consent. This is especially important for those patients who are known to be more prone to express regret following the procedure.  相似文献   
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Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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