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1.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure. 相似文献
2.
目的 建立一种可靠、简便的非同位素PCR方法检测脆性X综合征的突变基因。方法 采用生物素标记的CGG寡核苷酸探针,检测通过PCR扩增的FMR-1基因中CGG三核苷酸重复序列数目。从而判断所检样品中FMR—1基因是否正常。结果 该法可检测出正常人及携带者的CGG重复拷贝数。结论 该方法可以简便、安全、可靠地检测FMR—1基因中(CGG)n重复拷贝数,从而确定为正常人或携带者,可作为临床上筛查脆性X综合征的首选方法。 相似文献
3.
Helena Malmgren Karl-Henrik Gustavson Jan Wahlstrm Ingrid Arpi-Henriksson Jurgen Bensch Ulf Pettersson Niklas Dahl 《American journal of medical genetics. Part A》1992,44(6):830-833
Twenty-two members of 18 families with autism have been examined for the presence of mutations and abnormal methylation in the FMR-1 region at Xq27.3. All patients fulfilled diagnostic criteria of infantile autism. A characteristic pattern of insertion and methylation were detected after Southern blot analysis in 7 autistic individuals expressing the fragile site at Xq27.3. Normal DNA patterns were observed in 15 autistic boys cytogenetically negative for the fragile site. The results indicate a lack of involvement of the FMR-1 region in infantile autists negative for fragile X expression. © 1992 Wiley-Liss, Inc. 相似文献
4.
肘关节后脱位伴桡骨头和尺骨冠突骨折 (恐怖三联征)5例初步报告 总被引:12,自引:0,他引:12
[目的]介绍"肘关节恐怖三联征"的概念(肘关节后脱位同时伴有桡骨头和尺骨冠突骨折),并报告5例患者的临床治疗体会。[方法]自2004年4月~2007年3月,作者共收治肘关节三联征损伤5例。桡骨头骨折按Mason法分类:Ⅱ型4例,Ⅲ型1例;按Schatzker法分类:Ⅰ型1例,Ⅱ型3例,Ⅲ型1例。尺骨冠突骨折按Regan-Morrey法分类:Ⅰ型1例,Ⅱ型4例;按O′Driscoll法分类:5例均为Ⅰ型。4例采取了手术内固定治疗,以3 mm钛空心拉力螺钉或1 mm K针分别固定冠突和桡骨头,并缝合修复肘内外侧副韧带。术后屈肘90°前臂旋转中立位石膏外固定3周,开始屈伸和旋转康复训练。[结果]4例手术治疗的患者经3个月~3年随访,骨折愈合,肘关节稳定,无疼痛。肘关节屈伸幅度平均120°,前臂旋转幅度平均110°。3例随访1年以上,Mayo肘关节功能评分:优2例,良1例。未手术治疗的1例功能评定为差,有肘关节不稳定和疼痛。[结论]肘关节恐怖三联征的骨折片虽然很小,但伴有肘内外侧副韧带撕裂,肘关节严重不稳定。只有在重建了骨关节和软组织结构稳定的基础上,及早(3周内)进行康复锻炼,才能获得较好的功能恢复。 相似文献
5.
Li Shihong Schöneich Christian Wilson George S. Borchardt Ronald T. 《Pharmaceutical research》1993,10(11):1572-1579
The effect of primary structure and external conditions on the oxidation of methionine to methionine sulfoxide by the ascorbate/Fe3+ system was studied in small model peptides. Degradation kinetics and yield of sulfoxide formation were dependent on the concentration of ascorbate and H+, with a maximum rate observed at pH 6–7. Phosphate buffer significantly accelerated the peptide degradation compared to Tris, HEPES, and MOPS buffers; however, the formation of sulfoxide was low. The oxidation could not be inhibited by the addition of EDTA. Other side products besides sulfoxide were observed, indicating the existence of various other pathways. The influence of methionine location at the C terminus, at the N terminus, and in the middle of the sequence was investigated. The presence of histidine in the sequence markedly increased the degradation rate as well as the sulfoxide production. The histidine catalysis of methionine oxidation occurred intramolecularly with a maximum enhancement of the oxidation rate and sulfoxide production when one residue was placed between the histidine and the methionine residue. 相似文献
6.
Klinefelter syndrome is a common cause for mental retardation of unknown etiology among prepubertal males 总被引:1,自引:0,他引:1
Klinefelter syndrome (KS) has not typically been associated with mental retardation (MR), however, in recent years a growing body of evidence suggested that KS boys often experience language deficits and academic difficulties. In this study, we screened DNA samples from 1205 patients originally referred for fragile X syndrome (FRAX) testing, because of MR of unknown etiology and detected 8 KS patients. A similar number of males in the same age group were found to have FRAX; 3 of them had a family history of FRAX. Based on these findings, KS might be the most common cause of MR of unknown etiology among prepubertal males. Because of the significant benefits of early recognition and treatment of KS, we emphasize the importance of cytogenetic testing of all prepubertal males with cognitive impairment even without dysmorphic features. 相似文献
7.
Grant R. Sutherland Elizabeth Baker Antonio Fratini John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1985,22(2):433-443
Folate sensitive fragile sites on human chromosomes have been found to be inducible in cultured lymphocytes by high levels of thymidine but not by high levels of BrdU. The biochemical interpretation of events leading to fragile site expression has been revised since it is now clear that low levels of either thymidylate or deoxycytidine triphosphate will result in this phenomenon. A model for the DNA at a fragile site, composed of alternating repeating polypurine/polypyrimidine sequences is proposed. 相似文献
8.
Summary The fragile X syndrome is a common familial form of mental retardation and is associated with a rare fragile site at Xq27.3 (FRAXA). This disorder has recently been reported to correlate with length variations of restriction genomic DNA fragments which may due to the amplification of (CCG)n trinucleotide repeats located at the FRAXA locus. We described here a rapid preparation method of diagnostic DNA probes for the fragile X syndrome by direct enzymatic amplification of human chromosomal DNA. ThePstI-assay, which is Southern blot analysis of DNA samples probed by PCR products, was shown to be sensitive method for diagnostic purposes to detect the size variations specific in the fragile X syndrome. 相似文献
9.
Mianserin (5-20 mg/kg), like chlordiazepoxide (2.5-10 mg/kg), inhibits the shock-induced suppression of drinking (SSD) in rats. However, in contrast to chlordiazepoxide, the effect of mianserin is not blocked by the benzodiazepine antagonist, Ro 15-1788 (10 mg/kg). Although mianserin does not inhibit [3H]diazepam binding in vitro it has now been found to enhance [3H]flunitrazepam binding to mouse whole brain in vivo at 10-100 mg/kg p.o. These results suggest that mianserin does influence central benzodiazepine receptors, but the mechanism by which it does so differs from that of chlordiazepoxide. 相似文献
10.
Robin M. Winter Martin D'A. Crawfurd Hylton B. Meire Nan Mitchell 《Clinical genetics》1980,18(6):462-474
Cranial sclerosis with osteopathia striata was diagnosed in four members of a family in three generations. The expression of the gene varied from mild cranial enlargement to cranial abnormality associated with severe Pierre-Robin triad. The disorder was diagnosed prenatally in the most severely affected member of the family from the finding of an increased biparietal diameter of the fetal head on ultrasound examination. 相似文献