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101.
Success of meniscal repair with early or immediate motion depends on the ability of the suture fixation to withstand the loads applied. Vertical and horizontal mattress suture techniques were tested using 2-0 Ethibond, and 0-PDS and 1-PDS sutures (Ethicon, Somerville, NJ). Mulberry knot technique was tested with 0-PDS and 1-PDS sutures. Twenty menisci (60 sutures) were tested for each suture material. Sutures were placed 3 to 4 mm from the peripheral edge of the meniscus with double barreled cannulas for vertical and horizontal mattress techniques or a spinal needle for the mulberry knot technique, reproducing clinical techniques of meniscal repair. Mechanical testing of suture fixation was performed to failure at a rate of 10 mm/min on a MTS material testing system (MTS Systems Corp. Minneapolis, MN). Suture pullouts were reported as the load displacement to failure from the inner fragment only, because clinical failure would ensue should a suture pull through the inner fragment of a tear. Vertical mattress technique with 1-PDS suture had significantly greater load to failure than any other combination (P < .05). Analysis of variance showed that the vertical mattress technique had statistically superior pullout strength (P < .0001) compared with the horizontal mattress and mulberry knot techniques, which were statistically similar. There were significant differences (P < .0001) between suture types, with 1-PDS proving best compared with 0-PDS, which was stronger than 2-0 Ethibond. Selection of suture material had the greatest impact on vertical mattress load to failure and was not important to the strength of the other techniques. 相似文献
102.
先天性心脏病患儿肺动脉,上腔静脉血一氧化氮含量检测及意义 总被引:1,自引:1,他引:0
目的:探讨一氧化氮(NO)与先天性心脏病(CHD)引起的肺动脉高压(PH)发病间的关系。方法:应用NO试剂盒检测了CHD患儿肺动脉及上腔静脉血浆中NO含量。结果;(1)伴PH组肺动脉血浆NO含量明显高于不伴肺动脉高压组(37.58±9.99μmol/L:19.03±15.25μmol/L,P<0.01);(2)在PH组中,肺动脉血浆NO含量明显高于上腔静脉血(P<0.01);而不伴PH组,肺动脉和上腔静脉血浆NO含量无显著性差异(P>0.05)。结论:(1)伴PH的先心患儿肺动脉血浆NO含量升高;(2)NO可能介入了CHD引起的PH发病过程。 相似文献
103.
104.
M. F. Gagnadoux J. L. Bacri M. Broyer R. Habib 《Pediatric nephrology (Berlin, Germany)》1989,3(1):50-55
Over a 15-year period we observed seven children (four girls, three boys) who presented within the first months of life with severe renal failure and acidosis, associated with hypertension in five patients and polyuria in four. In addition, one patient had a severe cholestatic liver disease. In two families, a similarly affected sibling had died previously. Four patients were referred with the clinical diagnosis of polycystic kidney disease because of moderate enlargement of kidneys, but renal imaging (intravenous pyelography and ultrasonography) did not confirm this diagnosis. A renal biopsy, performed in all patients, showed similar features characterized by a diffuse chronic tubulo-interstitial nephritis (TIN) and particularly by the presence of microcystic dilatation of proximal tubules and Bowman's space. Liver pathology was normal in two patients, including one with hepatomegaly. However, in the patient with cholestasis there was inflammatory portal fibrosis with mild duct proliferation. Progression of the renal disease was extremely rapid and all patients reached end-stage renal failure (ESRF) before the age of 2 years (11–22 months). Two children had successful renal transplants. Although this chronic TIN shares some features with nephronophthisis, we suggest that it represents a distinct entity both on clinical and morphological grounds. The specific clinical features of this disease are its early onset and rapid progression to ESRF. Pathologically, it differs from nephronophthisis by the absence of medullary cysts and thickened tubular basement membranes and by the presence of cortical microcysts. 相似文献
105.
利福平引起的急性肾功能衰竭及其机制研究(3例报告及文献复习) 总被引:2,自引:0,他引:2
目的:探讨利福平致急性肾功能衰竭的临床病理特点及其发病机制。方法:对3例因利福平所致的急性肾衰竭患者的临床、肾脏病理进行分析,并采用抗人球蛋白试验方法检测患者的抗利福平抗体。结果:3例患者均有前驱感染史,临床主要表现为发热、胃肠道症状,随即出现无尿,伴随肾功能损害、血小板减低及溶血性贫血,部分伴有肝功能损害。肾活检3例均为急性肾小管坏死。3例的血清抗利福平抗体检测均为阳性。结论:利福平可引起急性肾衰竭,对应用利福平的患者应加强对肾功能的监测,肾脏病理及血清抗利福平抗体的检测有助于确诊。 相似文献
106.
目的 探讨黄芪注射液对心力衰竭 (HF)的治疗效果。方法 选择 92例住院HF患者随机分为治疗组和对照组 ,对照组给予常规治疗 ,治疗组在常规治疗的基础上给予黄芪注射液 30ml加 5 %葡萄糖液 2 5 0ml,静滴 ,每日一次 ,共 2周。疗程结束后 ,观察心功能改善情况。结果 治疗组有效率 93.4 8% ,对照组有效率 71.74 % ,两组对比 ,差异显著 (P <0 .0 1)。结论 黄芪注射液对HF的治疗效果佳 ,副作用少 ,值得推广。 相似文献
107.
目的:探讨冠心病心力衰竭对各种室性心律失常的影响。方法:选择381例冠心病住院患者,根据心功能分级标准(NYHA)分为4组,检测24h动态心电图(Holter),分析室性心律失常类型及发生率,进行统计分析。结果:各级心功能组其室性心律失常发生率经x^2检验示,室性心律失常的发生率除联律和持续性或非持续性室性心动过速外各组间差异无显著性(P>0.05)。结论:非心肌梗死冠心病患者室性心律失常发作频率与心力衰竭的程度无关,但联律和持续或非持续性室性心动过速在重度心力衰竭患者发生率增加。 相似文献
108.
ANDREW SHERWOOD SUSAN S. GIRDLER EDITH E. BRAGDON SHEILA G. WEST KIMBERLY A. BROWNLEY ALAN L. HINDERLITER KATHLEEN C. LIGHT 《Psychophysiology》1997,34(2):185-191
In this study we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates. 19 years of age at initial testing, and 29 years of age at follow-up testing Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression. 相似文献
109.
110.
The chest x-ray has become a standard clinical test to aid in the evaluation of patients with chronic severe heart failure. To evaluate just how useful this tool is in the routine assessment of pulmonary venous hypertension secondary to heart failure, we compared the radiologist's interpretation of the chest x-ray with hemodynamic data obtained from right heart catheterization in a group of patients undergoing protocol evaluation of an experimental treatment for heart failure. Of 23 patients with pulmonary venous hypertension (pulmonary capillary wedge pressure greater than 20 mmHg) and a complete data base, only 11 had chest x-rays showing evidence of pulmonary venous congestion or interstitial or alveolar edema. The sensitivity of the chest x-ray in selecting patients with a pulmonary capillary wedge pressure over 20 mmHg in this setting was only 48%. In other studies, where the radiologist was aware that his or her reading was being compared to hemodynamic assessments, the sensitivity of the chest film has approached 85%. We feel our analysis more closely parallels routine clinical practice. Clinicians should be aware that the chest x-ray may not be a very sensitive tool for the assessment of pulmonary hemodynamics in patients with severe heart failure. 相似文献