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991.
正常角膜基质细胞密度和角膜厚度的研究 总被引:4,自引:2,他引:4
目的观察Confoscan 2.0共焦显微镜下正常活体角膜影像表现,测量基质细胞密度与各层厚度.方法检查34例(48眼)正常人.记录图像,并计算基质细胞密度和各层厚度.结果基质细胞密度从前到后逐渐降低,前基质比后基质细胞密度明显增高(t=-9.016,P=0.000),Bowman膜下密度最高,为(1113.2±227)个/mm2.全基质细胞密度为(806.5±57)个/mm2.角膜中央厚度为(568.3±53.8)μm,基质层为(465.5±60.2)μm,上皮层为(58.5±20.4)μm.各层厚度均与全基质细胞密度无显著相关性(P>0.05).结论Confoscan 2.0共焦显微镜能检测角膜基质细胞密度和各层厚度. 相似文献
992.
目的回顾分析近10年PVR B级的裂孔性视网膜脱离术后复发与玻璃体病变的关系.方法对429例(435只眼)PVR B级的裂孔性视网膜脱离施行巩膜扣带术治疗,其中41只眼术后复发(9.43%),分析术后复发与玻璃体病变的关系.结果术前玻璃体正常组与浓缩组的复发率(3.19%与12.33%)之间差异有显著性(P<0.05);正常组与条索牵引组间的复发率(3.19%与14.29%)之间差异有极显著性(P<0.01);正常组与总体组的复发率(3.19%与9.43%)之间差异有显著性(P<0.05);术前无玻璃体后脱离组与玻璃体后脱离组间的复发率(5.56%与12.90%)之间差异有显著性(P<0.05).视网膜脱离术前各种玻璃体的情况在视网膜脱离复发时均有不同程度地加重.结论PVR B级的裂孔性视网膜脱离术前玻璃体病变和玻璃体后脱离对术后复发影响明显.重视玻璃体-视网膜界面动态变化,可进一步提高手术治愈率. 相似文献
993.
Tynan MC Fornalski S McMahon PJ Utkan A Green SA Lee TQ 《The Journal of bone and joint surgery. American volume》2000,(12):1726-1731
BACKGROUND: Forearm fractures are common injuries in both adults and children. Despite efforts to obtain anatomical alignment, axial rotational malunions occur, resulting in a decreased range of motion and a poor appearance. The objective of this study was to quantify loss of forearm rotation after simulation of ulnar malunions in supination and pronation. METHODS: Six fresh-frozen cadaveric upper extremities (mean age at the time of death, 79.4+/-2.8 years) were used to quantify loss of forearm rotation after simulation of axial rotational malunions of the ulna. First, maximum forearm rotation in supination and pronation was measured at torques of 6.8, 13.6, and 20.4 kilograms-centimeter applied with use of a custom jig. Following a midshaft ulnar osteotomy, a custom adjustable internal fixation plate was used to simulate axial rotational malunions of the ulna of 0, 15, 30, and 45 degrees in both directions. Measurements in supination and pronation were then repeated at the prespecified torques. Analysis of variance, with a p value of 0.05, was used for statistical analysis. RESULTS: In all instances, a decrease in forearm rotation after simulation of the ulnar rotational malunion was accompanied by an increase in rotation in the opposite direction. Supination and pronation were significantly influenced, whereas the total arc of rotation was not affected by ulnar rotational malunion. At a torque of 20.4 kilograms-centimeter, pronation malunions of 15, 30, and 45 degrees resulted in a mean loss of supination (and standard error of the mean) of 5+/-1, 11+/-1, and 20+/-1 degrees, respectively, and supination malunions of 15, 30, and 45 degrees resulted in a mean loss of pronation of 4+/-1, 10+/-2, and 18+/-4 degrees, respectively. The ratio of the simulated rotational malunion to the loss of motion was larger than one. CONCLUSIONS: Ulnar rotational malunions do not lead to a significant change in the total arc of forearm rotation. Instead, loss of motion in one direction is accompanied by increased motion in the opposite direction. Even with a 45-degree ulnar rotational malunion, forearm rotation decreases no more than 20 degrees. 相似文献
994.
BACKGROUND: Two of the important predictors of mortality for trauma patients are the Glasgow Coma Scale and the respiratory rate. However, for intubated patients, the verbal response component of the Glasgow Coma Scale and the respiratory rate cannot be accurately obtained. This study extends previous work that attempts to predict mortality accurately for intubated patients without using verbal response and respiratory rate. METHODS: The New York State Trauma Registry was used to identify 1994 and 1995 victims of motor vehicle crashes (MVCs). For the subset of patients who were not intubated, we developed two statistical models to predict mortality: one did not contain verbal response or respiratory rate, and the other contained a predicted verbal response. These were compared with a model that did include verbal response and respiratory rate. We also compared the predictive abilities of the first two models for all MVC patients (intubated and nonintubated) and determined the extent to which intubated patients were at increased risk of dying in the hospital after having adjusted for other predictors of mortality. RESULTS: For nonintubated patients, the statistical model without verbal response and the model with predicted verbal response had slightly better discrimination and worse calibration than the model that included verbal response and respiratory rate. Predicted verbal response did not improve the strength of the model without verbal response. For all MVC patients (intubated and nonintubated), predicted verbal response was not a significant predictor of mortality when used in combination with the other predictors. Intubation status was a significant predictor, with intubated patients having a higher probability of dying in the hospital than patients with otherwise identical risk factors. CONCLUSION: Inpatient mortality for intubated MVC patients can be accurately predicted without respiratory rate or verbal response. There appears to be no need for predicted verbal response to be part of the prediction formula, but intubation status is an important independent predictor of mortality and should be used in statistical models that predict mortality for MVC patients. 相似文献
995.
Rajan N Pruden DL Kaznari H Cao Q Anderson BE Duncan JL Schaeffer AJ 《The Journal of urology》2000,163(2):616-622
PURPOSE: Adherence of type 1 piliated Escherichia coli to vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections (UTIs) in women. Progress in understanding the mechanism of adherence to the vaginal surface could be enhanced by the utilization of well-characterized vaginal epithelial cells. The objective of this study was to immortalize vaginal epithelial cells and study their bacterial adherence properties. MATERIALS AND METHODS: Primary vaginal cells were obtained from a normal post-menopausal woman, immortalized by infection with E6/E7 genes from human papillomavirus 16 (HPV 16) and cultured in serum free keratinocyte growth factor medium. RESULTS: Positive immunostaining with a pool of antibodies to cytokeratins 1, 5, 10 and 14 (K1, K5, K10 and K14) and to K13 confirmed the epithelial origin of these cells. The immortalized cells showed binding of type 1 piliated E. coli in a pili specific and mannose sensitive manner. CONCLUSION: This model system should facilitate studies on the interaction of pathogens with vaginal mucosal cells, an essential step in the progression of ascending UTIs in women. 相似文献
996.
997.
儿童塑型性支气管炎的诊断与治疗 总被引:21,自引:0,他引:21
目的 报告 5例儿童塑型性支气管炎病例 ,并复习相关文献 ,总结诊断及治疗方法。方法 2 0 0 1年5月至 2 0 0 3年 10月 ,对 5例年龄 9个月至 10岁 ,主诉为反复咳嗽、气促并出现急性呼吸窘迫的塑型性支气管炎患儿 ,给予支气管镜检及气道内异物取出术 ,配以反复纤维支气管气道内冲洗、呼吸机机械通气、胸部物理治疗、强化护理及吸痰等综合治疗。结果 5例中 ,4例支气管镜检取出异物 ,1例为吸痰时吸出支气管状条形异物 ,经病理检查确诊。双侧支气管病变 1例 ,左侧支气管病变 2例 ,右侧支气管病变 1例 ,另 1例吸痰时可吸出。死亡 2例 ,其余 3例均痊愈出院。病理组织学分型按Seear方法 :Ⅰ型 3例 ,Ⅱ型 2例。结论 塑型性支气管炎是一种高危性疾病 ,确诊需依靠支气管镜检查和病理组织学检查。支气管镜异物取出术是唯一有效的治疗方法。气道护理和胸部物理治疗是重要的辅助治疗手段。 相似文献
998.
不同年龄组儿童阻塞性睡眠呼吸暂停综合征257例临床分析 总被引:5,自引:2,他引:5
目的 探讨儿童不同年龄组阻塞性睡眠呼吸暂停综合征 (OSAS)的主要病因、临床表现、睡眠监测及治疗方法。方法 分析广州市儿童医院耳鼻喉科 1999年 10月至 2 0 0 2年 9月收治的 2 5 7例OSAS患儿 ,分组分析病因 ,对所有患儿应用睡眠呼吸监护仪 ,并进行分度 ,针对不同的病因进行扁桃体摘除术和 (或 )腺样体刮除术。结果 ( 1)儿童OSAS最主要的临床表现依次为鼻鼾 ( 92 2 % ) ,张口呼吸 ( 89 5 % ) ,憋气 ( 6 7 3% ) ,易醒 ( 5 4 9% )等。 ( 2 )发病因素依次为腺样体增生 ( 91 8% ) ,扁桃体肥大 ( 6 9 6 % ) ,鼻窦炎 ( 5 8% ) ,过敏性鼻炎 ( 2 3% )。 ( 3)睡眠多导仪监测 (PSG)监测结果呼吸紊乱指数 (AHI)轻、中、重所占比例分别是 32 3%、4 9 8%、17 9%。氧饱和度下降轻、中、重所占比例分别是 8 5 %、5 6 0 %、35 4 %。 ( 4 )治疗方法主要是扁桃体摘除术 腺样体刮除术 ( 75 1% ) ,其次是腺样体刮除术 ( 15 2 % )和扁桃体摘除术 ( 9 7% )。结论 各年龄组儿童均可发生OSAS ,4~ 7岁是高发组。引起小儿OSAS的主要病因是扁桃体肥大和 (或 )腺样体增生。睡眠时鼻鼾、张口呼吸、憋气是儿童OSAS特征。确诊 分度依靠多导睡眠图 ,手术是治疗儿童OSAS的有效手段 相似文献
999.
Distinctive gene expression profiles by cDNA microarrays in endometrioid and serous carcinomas of the endometrium. 总被引:2,自引:0,他引:2
Q Jackie Cao Thomas Belbin Nicholas Socci Raluca Balan Michael B Prystowsky Geoffrey Childs Joan G Jones 《International journal of gynecological pathology》2004,23(4):321-329
Endometrial carcinomas are classified by their morphology into two major subtypes. Endometrioid carcinomas (type I) are generally estrogen dependent, well-differentiated, superficially invasive, and have a good outcome. Serous carcinomas (type II) are hormone independent, frequently deeply invasive and widely metastatic, and have a poor prognosis. Microarray technology and analysis allows us to determine if the global gene expression profiles of these two subtypes correlate with their morphologic phenotype. Fresh tissue from 18 endometrial carcinomas was studied: 7 well-, 2 moderately, and one poorly differentiated endometrioid, 4 serous carcinomas, and 4 high-grade mixed endometrioid-serous carcinomas. Labeled cDNA probes were synthesized (Cy5 for tumor, Cy3 for reference) and applied to microarrays containing 18,098 cDNA clones or ESTs. A pool of equal amounts of total RNA from each tumor served as the reference RNA. By unsupervised cluster analysis, the endometrioid carcinomas clustered together and were separate from the serous carcinomas. The high-grade mixed carcinomas clustered with the serous carcinomas. Using a statistical algorithm based on gene expression pattern and conducting a supervised analysis of the two defined groups, we have identified 315 genes that statistically differentiate type I from type II endometrial carcinomas. In addition to corroborating the predicted overexpression of known markers (e.g., ras and catenin in endometrioid carcinomas), the cDNA microarray technique has revealed novel alterations in gene expression relevant to cell cycle, cell adhesion, signal transduction, apoptosis, and tumor progression not previously implicated in endometrial carcinomas. For serous carcinomas, these include aldolase, desmoplakin, integrin-linked kinase, PKC, and metallopeptidase. In conclusion, the gene expression profiles of type I and type II endometrial carcinomas are different. Refinement of these profiles will permit more accurate diagnostic tumor classification and the development of prognosis assays. 相似文献
1000.
Construction of a bioengineered cardiac graft 总被引:19,自引:0,他引:19
Li RK Yau TM Weisel RD Mickle DA Sakai T Choi A Jia ZQ 《The Journal of thoracic and cardiovascular surgery》2000,119(2):368-375
OBJECTIVES: Currently available graft materials for repair of congenital heart defects cause significant morbidity and mortality because of their lack of growth potential. An autologous cell-seeded graft may improve patient outcomes. We report our initial experience with the construction of a biodegradable graft seeded with cultured rat or human cells and identify their 3-dimensional growth characteristics. METHODS: Fetal rat ventricular cardiomyocytes, stomach smooth muscle cells, skin fibroblasts, and adult human atrial and ventricular cardiomyocytes were isolated and cultured in vitro. These cells were injected into or laid onto biodegradable gelatin meshes, and their rate of proliferation and spatial location within the mesh was evaluated by using a cell counter and histologic analysis. RESULTS: Rat cardiomyocytes, smooth muscle cells, and fibroblasts demonstrated steady proliferation over 3 to 4 weeks. The gelatin mesh was slowly degraded, but this process was most rapid after seeding with fibroblasts. Human atrial cardiomyocytes proliferated within the gelatin meshes but at a slower rate than that of fetal rat cardiomyocytes. Human ventricular cardiomyocytes survived within the gelatin mesh matrix but did not increase in number during the 2-week duration of evaluation. Grafts seeded with rat ventricular cells exhibited spontaneous rhythmic contractility. All cell types preferentially migrated to the uppermost surface of each graft and formed a 300- to 500-microm thick layer. CONCLUSIONS: Fetal rat ventricular cardiomyocytes, gastric smooth muscle cells, skin fibroblasts, and adult human atrial cardiomyocytes can grow in a 3-dimensional pattern within a biodegradable gelatin mesh. Similar autologous cell-seeded constructs may eventually be applied to repair congenital heart defects. 相似文献