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P Ia Filiptsev Ia G Mo?siuk Iu V Luk'ianov 《Vestnik khirurgii imeni I. I. Grekova》1989,143(11):36-38
The work presents an experience with 84 operations of making nonstandard arteriovenous fistulas in 75 patients using autovenous transplants, polytetrafluorethylene prosthesis and home bioprostheses from human umbilical veins made at plant "Sever". Results of the operations were followed-up during 3 years. It was shown that arteriovenous fistulas made of plastic materials generally have a higher level of complications and shorter terms of functioning as compared with ordinary fistulas. Nevertheless, using nonstandard fistulas is justified in a certain category of patients. 相似文献
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Electrospun P(LLA-CL) nanofiber: a biomimetic extracellular matrix for smooth muscle cell and endothelial cell proliferation 总被引:26,自引:0,他引:26
Poly(L-lactide-co-epsilon-caprolactone) [P(LLA-CL)] with L-lactide to epsilon-caprolactone ratio of 75 to 25 has been electrospun into nanofibers. The relationship between electrospinning parameters and fiber diameter has been investigated. The fiber diameter decreased with decreasing polymer concentration and with increasing electrospinning voltage. The X-ray diffractometer and differential scanning colorimeter results suggested that the electrospun nanofibers developed highly oriented structure in CL-unit sequences during the electrospinning process. The biocompatibility of the nanofiber scaffold has been investigated by culturing cells on the nanofiber scaffold. Both smooth muscle cell and endothelial cell adhered and proliferated well on the P(LLA-CL) nanofiber scaffolds. 相似文献
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大学生性行为及性道德观发展研究 总被引:6,自引:0,他引:6
目的 了解当代大学生性行为及性道德观念的发展变化。方法 自制问卷,对全国9所高校的2000余名大学生进行调查,并用SPSS10.0对结果进行统计处理。结果 大学生性交行为发生率呈逐年上升趋势,且随年级上升而增加;大学生认可性交行为道德观的5个雏度,但各年级之间有差异;大学生边缘性行为和独自性行为发生率随年级显著上升,认可度也随年级增加而上升;大学生对同性性接触基本持排斥态度,但排斥态度则趋于下降。结论 大学生性行为和性道德随年级上升而明显变化,应加强学校教育和引导。 相似文献
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Rapid, accurate genotyping of the common -alpha(4.2) thalassaemia deletion based on the use of denaturing HPLC 下载免费PDF全文
AIMS: To develop an alternative assay for specific genotyping of the -alpha(4.2) thalassaemia deletion based on the DNA sequence features surrounding the breakpoint. METHODS: The 5' and 3' ends of the breakpoint regions of the -alpha(4.2) allele and the normal homologous segments were sequenced in Chinese individuals. A sequence haplotype composed of four single nucleotide variations within the X2/X1 box of the -alpha(4.2) breakpoint region was found in all of the 10 Chinese -alpha(4.2) thalassaemia alleles studied. Based on these findings, a novel polymerase chain reaction (PCR)/denaturing high performance liquid chromatography (DHPLC) assay was developed for rapid genotyping of the -alpha(4.2) allele instead of traditional Southern blotting or Gap-PCR. This method involves amplification of the alpha globin target sequence encompassing these four polymorphic sites, followed by a partially denaturing HPLC analysis using the transgenomic WAVE DNA fragment analysis system. RESULTS: The three major genotypes (-alpha4.2/alphaalpha, -alpha(4.2)/--SEA, and alphaalpha/alphaalpha) could be distinguished through the characteristic chromatograms generated by the WAVE system. The accuracy of this technique was evaluated blindly, and the results were 100% (40 of 40) concordant with the genotypes previously characterised by Southern blotting or Gap-PCR. CONCLUSIONS: This study validates the PCR/DHPLC approach as a simple, rapid, highly accurate, and cost effective method, potentially adaptable for use in epidemiological surveys, genetic screening, and diagnosis of silent alpha+ thalassaemia and Hb H disease. 相似文献
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We report a case of papillary carcinoma arising in a thyroglossal duct cyst, presenting with an anterior neck mass of a 31-year-old woman. The tumor was judged to be a primary lesion on the basis of intraoperative examination of the thyroid and pathologic findings of the mass. One year later, a small nodular mass in the left thyroid gland and lymph node enlargement of the right cervical lymph node were noted by follow-up imaging studies. Total thyroidectomy, right modified radical neck dissection and central neck dissection were performed. The thyroid gland revealed nodular hyperplasia without evidence of malignancy. On the other hand, the dissected neck lymph nodes revealed metastatic papillary carcinoma. Taken together, these findings suggested the tumor was a primary papillary carcinoma arising in the thyroglossal duct cyst. 相似文献
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吗氯贝胺与米帕明治疗抑郁症多中心双盲对照试验 总被引:3,自引:0,他引:3
目的 :以经典抗抑郁药物米帕明为阳性对照药采用随机双盲双模拟方法对吗氯贝胺和米帕明治疗抑郁症的疗效和安全性进行研究。方法 :共纳入病人 2 0 0例 ,分别口服吗氯贝胺 3 0 0 -60 0mg d或米帕明75 -2 5 0mg d。结果 :两组病人Hamilton抑郁量表 (HAMD)以及Hamilton焦虑量表 (HAMA)总分在治疗结束时均显著下降 (P <0 0 0 1)。两组之间疗效无显著差异 (p >0 0 5 )。治疗结束时HAMD减分率分别为吗氯贝胺组 0 74± 0 2 4,米帕明组 0 74± 0 2 4(P >0 0 5 ) ;有效率吗氯贝胺组 79 4% ,米帕明组 85 4% (P >0 0 5 )。吗氯贝胺组有 10种不良反应发生频率显著低于米帕明组 ,主要是抗胆碱能、中枢神经系统及心血管系统不良反应。吗氯贝胺的疗效指数也显著高于米帕明组。结论 :吗氯贝胺是一种安全有效的抗抑郁药物 相似文献
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Missing data such as appropriateness ratings in clinical research are a common problem and this often yields a biased result. This paper aims to introduce the multiple imputation method to handle missing data in clinical research and to suggest that the multiple imputation technique can give more accurate estimates than those of a complete-case analysis. The idea of multiple imputation is that each missing value is replaced with more than one plausible value. The appropriateness method was developed as a pragmatic solution to problem of trying to assess "appropriate" surgical and medical procedures for patients. Cataract surgery was selected as one of four procedures that were evaluated as a part of the Clinical Appropriateness Initiative. We created mild to high missing rates of 10%, 30% and 50% and compared the performance of logistic regression in cataract surgery. We treated the coefficients in the original data as true parameters and compared them with the other results. In the mild missing rate (10%), the deviation from the true coefficients was quite small and ignorable. After removing the missing data, the complete-case analysis did not reveal any serious bias. However, as the missing rate increased, the bias was not ignorable and it distorted the result. This simulation study suggests that a multiple imputation technique can give more accurate estimates than those of a complete-case analysis, especially for moderate to high missing rates (30 - 50%). In addition, the multiple imputation technique yields better accuracy than a single imputation technique. Therefore, multiple imputation is useful and efficient for a situation in clinical research where there is large amounts of missing data. 相似文献