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131.
An unusual, elongated, refractile cell morphology was observed in keratinocytes cultured from three patients with non-lethalis forms of junctional epidermolysis bullosa (JEB). To determine whether these changes might be related to altered cell adhesion, keratinocyte strains established from one patient were examined for adhesive, structural, and functional characteristics. JEB keratinocytes expressed keratin tonofilaments, as determined by staining with AE1 monoclonal antibodies and direct observation of tonofilaments by electron microscopy. JEB keratinocytes showed diminished cell-substratum adhesions, judged by interference reflection microscopy. Areas of diminished cell-substratum adhesion corresponded to F-actin-rich cell adhesions (focal adhesions) and not to cellular areas that abundantly express hemidesmosomal antigens. Analysis of cell-substratum adhesion by electron microscopy revealed extensive areas of cell-substratum separation in JEB keratinocytes that were not present in normal keratinocytes maintained in serum-free medium. Normal keratinocytes displayed numerous regions of focal contact between the ventral plasma membrane and the culture substratum, but these structures were not seen in JEB keratinocytes. Bundled actin filaments (stress fibers) were greatly diminished in expected regions of cell-substratum adhesion in JEB keratinocytes and, instead, displayed disorganized individual filaments. The growth rate of JEB keratinocytes was quite slow in culture, with a population doubling time of 2.7 d versus 1.5 d for normal keratinocytes under identical conditions. JEB keratinocytes also displayed a reduced ability to aggregate into colonies upon exposure to medium with increased extracellular calcium. JEB keratinocytes thus display adhesive, structural, and functional abnormalities that suggest this cell type may be central to the pathogenesis of junctional epidermolysis bullosa. Study of affected keratinocytes could be important to characterize associated molecular pathologies.  相似文献   
132.
Overexpression of wound healing-promoting factors such as transforming growth factor-1 (TGF-beta1) and insulin-like growth factor-1 (IGF-1) during the healing process has been implicated in the development of dermal fibrosis in patients following thermal injury, surgical incision, and deep trauma. However, the mechanism through which the expression of these two fibrogenic factors is slowed down and/or abrogated in the late stages of the healing process is not known. Here, we hypothesize that keratinocyte-releasable factors counteract the fibrogenic role of both IGF-1 and TGF-beta1 in fibroblasts. To test this hypothesis, the levels of collagenase (MMP-1), as an index for extracellular matrix degradation, in dermal fibroblasts in response to either keratinocyte-conditioned medium (KCM) or our recently identified keratinocyte-releasable stratifin in the presence and absence of either IGF-1, TGF-beta1, or both were evaluated. The results of Northern analysis showed a significant increase in collagenase mRNA expression in cells treated with KCM in the presence of both IGF-1 and TGF-beta1. The effect was, at least in part, due to keratinocyte-derived stratifin that was present in KCM. This was ascertained as the levels of MMP-1 mRNA were markedly reduced when cells were treated with stratifin-immuno-depleted KCM. The results of Western blot analysis showed an increase in the level of MMP-1 protein in stratifin-treated fibroblasts and this was consistent with the level of MMP-1 mRNA expression detected by Northern analysis. However, in contrast to KCM, whose efficacy on MMP-1 expression was modestly reduced by either IGF-1 and TGF-beta1, or a combination of both, these factors abrogated the MMP-1 stimulatory effect of stratifin in fibroblasts. In summary, the results of this study revealed that both stratifin and KCM stimulate the expression of MMP-1-in fibroblasts and this effect can be abrogated by either IGF-1, TGF-beta1, or a combination of both.  相似文献   
133.
Teh-Ia Huo  Han-Chieh Lin  Shou-Dong Lee 《Liver transplantation》2007,13(11):1618; author reply 619-1618; author reply 620
  相似文献   
134.
阴茎勃起神经再生模型和机制的研究   总被引:1,自引:0,他引:1  
探明神经性勃起功能障碍(NED)的分子生物学机制以期对该类疾病进行神经调控干预,是男科学研究的当务之急。本文回顾了急性神经损伤、前列腺癌、糖尿病和帕金森病所致的NED的研究进展。通过利用大鼠阴茎勃起神经的盆腔大神经节(MPG),在体外构建一个三维培养体系来研究各种生长因子和细胞信号通路对神经再生的影响。体外结果表明脑源性神经生长因子(BDNF)通过JAK/STAT信号通路可显著促进NED的恢复,并在体内证实了该效应。因此,通过调控JAK/STAT信号通路来达到神经调控干预措施预防治疗神经性勃起功能障碍成为可能。  相似文献   
135.
BACKGROUND AND PURPOSE: Taiwan's National Health Insurance (NHI) program has considered the use of capitation payments to health care providers as a method for control of the rising costs of the system. The establishment of capitation payments usually requires the performance of risk adjustment. The purposes of this study were to develop a diagnosis-based risk adjustment model for the NHI and to evaluate its predictability. METHODS: Using a 2% random sample of 371,620 NHI enrollees, the authors developed a Taiwan version of the Principal Inpatient Diagnosis Cost Groups (TPIPDCGs) from 1996 claim records to predict an individual's expenditure in 1997. Weighted least squares regression models were built in an estimation sample (two-thirds of the study sample), and were cross-validated in a validation sample (the remaining one-third of the study sample). Predictive R2 and predictive ratios were used to evaluate the model's predictability. RESULTS: Only 7.88% of the study sample could be classified into 1 of the 16 TPIPDCGs. Combined with demographic variables, which alone could explain 3.7% of the variation in an individual's future expenditure, the risk adjustment model based on TPIPDCGs could explain 12.2% of expenditure variation. In addition, the finding that the predictive ratios of the TPIPDCG model approximated unity better than those of the demographic model in all subgroups indicates that the capitation payment as predicted by the TPIPDCG model for each subgroup would better correlate to the actual spending. CONCLUSION: Taiwan's risk-adjusted capitation model based on principal inpatient diagnoses has higher predictability on individual's future expenditure than its counterpart in the USA. This finding provides insight into not only the development of Taiwan's diagnosis-based risk adjustment models but also the necessity of modification when applying foreign-developed risk adjustment models to the NHI.  相似文献   
136.
目的对比研究动脉血质子自旋标记(ASL)与动态磁敏感对比(DSC)MRI在急性脑缺血诊断中的应用价值。方法27例发病3d内的急性脑卒中患者,均采用3.0TMR行脉冲式ASL和DSCMR检查。观察2种技术的灌注表现,包括灌注不足、正常灌注、延迟灌注、过度灌注等,采用Mann—Whitney检验做定性分析。在扩散加权成像显示的病变部位及对侧正常半球的镜像区域分别确定3个感兴趣区(ROI),测量信号强度并计算信号强度比(病侧/对照侧),并将结果做配对t检验。结果定性分析显示27例患者中,2l例2种技术检查结果一致(灌注不足14例,正常灌注5例,过度灌注2例)。6例2种技术不一致,其中4例ASL显示灌注不足而DSC显示延迟灌注,2例ASL显示正常灌注而DSC显示延迟灌注,两者间差异无统计学意义(P〉0.05)。定量分析示,2种技术的病侧与对照侧信号强度比值ASL为0.7l±0.46,DSC为0.73±0.42,两者间差异无统计学意义(P〉0.05)。结论无创性ASL技术在检测灌注异常时与DSCMRI有相似的敏感性;ASL可与常规MR检查相结合,为临床诊断急性缺血性卒中提供有价值的信息。  相似文献   
137.
目的探讨小角度弯曲针穿刺法进行腰5-骶1椎间盘或低位腰4~5椎间盘介入治疗的方法和应用效果。方法对50例明显低于髂嵴的腰4-5或腰5-骶1椎间盘突出症患者采取小角度弯曲针法穿刺椎间盘进行介入治疗。透视下旋转血管机的C型臂,使射线方向与椎间隙平行,将皮肤穿刺点位于距离脊柱中线6~8cm处,常规消毒麻醉;将穿刺针的前端2~3cm向一侧弯曲20°后向椎间盘穿刺,侧位观察接近椎间盘后缘时,将穿刺针弯曲端偏向内侧、上方进入椎间盘后外侧部,然后进行椎间盘内臭氧注射或等离子消融治疗。结果椎间盘穿刺顺利,一次穿刺成功者45例,占90%,穿刺针进入椎间隙后多数与椎间隙平行,利于盘内介入操作(40/50,占80%),仅20%穿刺后针尖位置欠理想,但尚可完成臭氧注射溶核。经穿刺针向盘内注射臭氧分布良好,等离子刀头活动范围适合消融需要,手术后近期有效率96%,无明显穿刺并发症。结论小角度弯曲针法可以避免高位髂嵴对低位椎间盘穿刺的限制,提高穿刺针在椎间盘内的位置精度,有利于顺利施行介入处理,减少穿刺损伤,缩短手术时间。  相似文献   
138.
Background: To date, no study has explored the effect of bent length on lightwand intubation. For successful intubation in daily practice, the authors found that bent length should be approximated to the patient's thyroid prominence-to-mandibular angle distance (TMD), but some patients have a TMD much shorter than the suggested bent length range. The purposes of this study were to understand TMD distribution in adults and to test the influence of bent length on lightwand intubation.

Methods: The TMD, airway, and demographic data of 379 patients were collected. To test the bent length influence, patients were enrolled in group A (158 patients, TMD <= 5.5 cm) and group B (131 patients, TMD > 5.5 cm) and were intubated randomly using the lower (6.5 cm) and upper (8.5 cm) limits of the suggested range. Success rate and lightwand search time were compared.

Results: In group A, the success rate was 98.8% with 6.5-cm bent length and 78.2% with 8.5-cm bent length (P < 0.05). Search times were 5.7 +/- 2.90 and 8.9 +/- 5.80 s with 6.5- and 8.5-cm bent length, respectively (P < 0.01). In group B, there was no statistical difference in success rate and search time between 6.5- and 8.5-cm bent length.  相似文献   

139.
林湛雁 《现代医院》2005,5(9):126-128
深圳市第二人民医院在不断完善、加大力度、加强医德医风建设方面制订出一系列纠风长效机制,采取有力措施:认真解决“红包”、回扣问题;进一步推动和规范药品集中招标采购工作;加强对中标药品价格和管理;切实加强医德医风建设,规范医疗服务行为;进一步规范药品生产流通秩序,加大源头治理力度;加强监管,严肃查处医药购销和医疗服务中的违纪违法行为。使医德医风常抓不懈,为医院在医疗服务行业、深化改革竞争中赢得了一席之地,也使医院在社会效益和经济效益能在全社会中取得了较高威信奠定了坚实的基础。  相似文献   
140.
OBJECTIVE: To evaluate the relationship between the left ventricular hypertrophy (LVH) and the ambulatory pulse pressure and aortic root dimension (AOD) in essential hypertensive patients. METHODS: We monitored the 24-hour ambulatory blood pressure and applied echocardiography in 107 essential hypertensive patients. Using the left ventricular mass index (LVMI) as an index in evaluating LVH, the patients were divided into 2 groups: 29 cases in the LVH group and 78 in the non-LVH group. RESULTS: The average levels of 24-hour pulse pressure, daytime pulse pressure, nighttime pulse pressure and AOD were significantly different between patients with LVH and without LVH (P < 0.05). Multiple stepwise regression analysis showed that the changes in nighttime pulse pressure and AOD were closely related to LVMI (P < 0.001). CONCLUSION: The pulse pressure and AOD are important factors leading to LVH in patients with essential hypertension.  相似文献   
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