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151.
生物活性陶瓷与细胞外基质骨形成对Ca、P、ALP影响   总被引:2,自引:0,他引:2  
目的:通过钙(Ca)、磷(P)及碱性磷酸酶(ALP)评价,探讨生物活性陶瓷及细胞外基质与骨细胞相互作用机理,为骨替代材料成骨效应提供依据。方法:选用多种材料进行蒸馏水及血浆接触,体外成骨细胞培养及体内骨诱导试验。采用原子吸收,钼蓝比色及速率法分析化学性能,血浆、细胞冻溶液及组织匀浆中Ca、P、ALP的变化规律。结果:材料组体内、外接触Ca、P、ALP值高于对照组。细胞外基质复合材料组高于相应的非复合材料组。TGF-β1加材料高于BMP复合材料组,而不同材料有所不同,TCP材料高于其它材料。结论:生物活性陶瓷材料均有不同程度的Ca、P离子释放,细胞外基质及Ca、P离子可提高成骨细胞活性,异位骨形成及ALP活性。  相似文献   
152.
左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价   总被引:21,自引:3,他引:18  
目的 探讨左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价。方法 回顾性分析我院1994年2月期间至2003年2月采用一期切除吻合术治疗左半结肠癌并发急性肠梗阻64例的l临床资料。结果 全组患者无死亡及腹腔感染。7例(10.9%)发生切口感染,3例(4.7%)发生吻合口漏,均治愈。住院时间10~36d,平均16d。结论 部分经选择的病例中开展一期切除吻合术是安全、可行的,选择性应用一期切除吻合术是治疗左半结肠癌并发急性肠梗阻的理想术式。  相似文献   
153.
Using a prospective hospital-based registry, 146 patients with transient ischaemic attack (TIA) were compared with 376 patients with minor first-ever ischaemic stroke with respect to the 3-month risk of subsequent vascular events, in order to clarify the distinctions between the disease entities. All patients were enrolled within 48 h of onset. The risk factor distribution for the two groups was comparable, except that the TIA patients had more previous TIAs. Large artery atherosclerosis (34%) and small vessel occlusion (32%) were the main aetiologies in the TIA group, whereas small vessel occlusion (49%) was the major cause in the stroke group. The 3-month risk of combined endpoints of stroke, myocardial infarction, and vascular death for TIA patients was higher than that for the minor stroke group (15.1% vs. 3.2%; hazard ratio 4.6, 95% confidence interval 2.3-9.3 in multivariate analysis). Large artery atherosclerosis and male sex were the other significant predictors. TIA may demand more urgent management than minor stroke. The fact that aetiology is a predictor, highlights the need for rapid diagnostic tests to establish pathogenesis.  相似文献   
154.
155.
以含有次级孔的沸石的晶内扩散为研究对象,对来源于同一NaY母体的一组改性Y型沸石,进行了孔结构分析和正戊烷的扩散系数的测定。得到了具不同次级孔量的Y型沸石晶内扩散性能变化的规律。并采用随机游动方法对实际的Y型沸石晶内扩散进行模拟,得到了与实验测定一致的结果,从而可以对有次级孔的Y型沸石的晶内扩散做定量的估计。  相似文献   
156.
157.
人工全髋关节术后脱位的预防及治疗   总被引:4,自引:3,他引:1  
孔畅  林定坤  邓晋丰  黄刚  赵帅 《中国骨伤》2003,16(11):677-678
术后髋关节脱位是人工全髋置换术(THR)后严重的并发症,如处理不善,常会引起严重的下肢功能障碍,导致关节手术失败.1994-2001年,我院共行THR手术436例,其中术后发生脱位有11例,加上外院转入5例,共16例,现报告如下.……  相似文献   
158.
 To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July 1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition, the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination. These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae. Received: 2 September 1996/Accepted: 29 November 1996  相似文献   
159.
The purpose of this study is to develop an evaluation instrument with high feasibility and acceptability, and to quantify the outcome of evaluation, in order to set up an efficient evaluation system. Teaching evaluation with questionnaire by students has been carried out in National Yang-Ming Medical College for two years. With the support of both teachers and students, the system has been established and conducted on a regular basis. The most important purpose of evaluation is to improve the quality of teaching. During the two academic years (Sep. 1986-June 1988) of the program, the overall response rate was 44.5%, the Department of Nursing had the highest response rate, followed by Dentistry, Medicine-Post Graduate, Medical Technology, and Medicine. Taking into consideration of the year and the class size, the regression analysis found that higher year or smaller size of the class had better response rate. The response rates dropped significantly after the first academic year regardless of department or year. A total of 23 classes were included in the evaluation program and 99 courses were evaluated. All questions in the questionnaire used a 0 to 4 ordinal scale, in which 0 (improvement needed) was the low end and 4 (excellent) the high end. The mean score of the seven questions of teaching evaluation was 2.47. As a whole, the students were satisfied with the teaching. As to the categories of courses, clinical courses had better mean score than basic medical courses, and basic medical courses had better mean score than common required courses. To evaluate the effectiveness of the teaching, students' achievement was used as the outcome variable. The most important predictive variable was the method of instruction, followed by the content of lecture such as degree of difficulty of the lecture and cognitiveness of the contents. The above 3 variables explained 76% of the variation of the students' achievement. However, the significant of teachers' speech, performance and attitude were not so influential. Analysis based on the characteristics of the teachers (sex, age, position, and teaching experience), the characteristics of students (department and year), teaching environments (time and place), and the 3 categories of courses (clinical, basic medical and common required courses) showed that all the above variables only explained less then 10% of the variation of the students' achievement.  相似文献   
160.
Non-tuberculous mycobacterial keratitis: a study of 22 cases.   总被引:11,自引:0,他引:11       下载免费PDF全文
AIM: To investigate causes and clinical findings of non-tuberculous mycobacterial keratitis, and to study its response to topical antibiotic therapy and surgical extirpative keratectomy. METHOD: A single centre, retrospective review of 22 patients with non-tuberculous mycobacterial keratitis seen in a 3 year period. Laboratory diagnoses were established with Ziehl-Nielsen acid fast staining and Löwenstein-Jensen cultures. RESULTS: In 20 patients (91%), there was an antecedent history of foreign body eye trauma (18 patients) or elective surgery (two patients). There were 19 cases of Mycobacterium chelonei, and three of M fortuitum. Clinical signs included epithelial defects, satellite or ring stromal infiltrates, crystalline keratopathy, and hypopyon. For topical antibiotic therapy, 20 patients received amikacin, while one patient received rifampin and another received ciprofloxacin, each in accordance with the results of the in vitro drug sensitivities. An extirpative keratectomy was performed in 15 cases; four of these cases additionally required a temporary conjunctival flap in order to finally eradicate the infection. At the end of the follow up period (median 18 months; range 3 months to 3 years) all eyes were stable and free of infection, with 19 (86%) having final visual acuities of 20/200 or better. CONCLUSION: Early clinical recognition and prompt laboratory diagnosis, together with aggressive topical antibiotic therapy and early keratectomy, may shorten morbidity and improve the clinical outcome of non-tuberculous mycobacterial keratitis.  相似文献   
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