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41.
带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎 总被引:1,自引:0,他引:1
目的:阐明带血管蒂岛状筋膜瓣移植治疗晚期类风湿性髋关节炎的疗效。材料和方法:对42例48髋晚期类风湿性髋关节炎病人采用以旋股外侧血管降支为蒂的股前外侧筋膜瓣移植行患髋成形术。结果:术后随访4~10.5年,平均4.5年,髋关节活动范围术前平均16.5°,术后228.6°,按照Charnley和吴之康人工髋关节置换术后的疗效评定标准,优良29髋、很好13髋、好6髋,尚可、差、很差无。结论:患者年龄在15~40岁之间为合适的治疗年龄。与人工髋关节置换术相比,本方法对髋关节正常结构破坏小;一旦手术失败仍可选用其它治疗方法弥补;且并发症少、费用低、远期效果好。 相似文献
42.
回顾医学美学与美容医学形成独立的学科系统的十多年来的发展历程,认为这个新兴学科在“整体学科”方面还存在一些学术问题有待人们进一步探讨。并认为,所谓“整体学科研究”是遵循该学科发展的内在规律所进行的各项研究的总和,是该学科发展的灵魂。学者们的任务在于:通过“整体学科研究”寻求其学科内在规律,经一代代同道有志者坚持不懈的努力,达到学科完善的目的。 相似文献
43.
Selection of Streptococcus pneumoniae Mutants Having Reduced Susceptibility to Moxifloxacin and Levofloxacin 下载免费PDF全文
With Streptococcus pneumoniae, moxifloxacin was 4- and 10-fold more effective than levofloxacin at restricting selection of resistant mutants and at killing resistant mutants, respectively. The selection frequency for first-step topoisomerase mutants was 1,000 times lower for moxifloxacin than for levofloxacin; this difference was lost when second-step mutants were selected. 相似文献
44.
目的 探讨在十二指肠乳头括约肌切开 (EST)胆总管取石术前静注咪唑安定的可行性及价值。方法 将 71例拟行 EST胆总管取石患者随机分为咪唑安定组 (试验组 ) 5 1例和对照组 (2 0例 ) ,两组术前均给予 6 5 4 -2 (10 mg)静脉注射 ,试验组同时静脉注射咪唑安定 (3~ 5 mg)。观察两组患者的进镜时间、麻醉程度 ,患者的反应与配合程度、自身感受程度 ,同时监测患者的血压、心率、血氧饱和度。结果 试验组进镜时间缩短、镇静程度适中、患者自身感受好 ,与对照组比较 ,差异有显著性 (P<0 .0 1) ;患者心血管及呼吸参数无明显变化。结论 EST胆总管取石术前静脉注射咪唑安定可提高麻醉效果 ,有利于提高患者配合的依从性 ,对血压、心率、血氧饱和度无明显影响 相似文献
45.
皮肤交界性平滑肌瘤的复发与恶性转化 总被引:3,自引:0,他引:3
目的探讨皮肤交界性平滑肌瘤的复发与恶性转化。方法复习2例皮肤交界性平滑肌瘤及其复发恶性转化的临床病理特征、免疫组化表型及相关文献。结果2例病变位于下肢和额部,肉瘤组织平滑肌标记阳性。结论少数病理诊断为皮肤平滑肌瘤的病例,虽然浅表且组织形态良性,但其生物学恶性潜能尚不能确定,部分病例复发后可转变为典型的平滑肌肉瘤。 相似文献
46.
Introduction There is now increasing evidence that proximal tubular cells (PTCs) contribute to renal interstitial fibrosis by alteration of matrix turnover and by the generation of pro‐fibrotic cytokines such as TGF‐β1. Recent studies suggest that, through a process of transdifferentiation, the PTCs are one source of the interstitial myofibroblasts that directly drive the fibrotic process. The aim of this work was to examine the role and mechanism by which TGF‐β1 may regulate PTC phenotype and function. Methods Experiments were performed using both primary‐cultures of PTC and the human PTC cell line HK2. All experiments were performed on growth‐arrested cells in the absence of serum. Results TGF‐β1 altered cell phenotype, assessed by light microscopy, with cells appearing elongated and spindle‐shaped. This was associated with loss of cell–cell contact and rearrangement of the actin cytoskeleton, increased formation of stress fibres and focal adhesions. Disruption of the actin cytoskeleton with cytochalasin‐D prevented phenotypic alterations following addition of TGF‐β1. Transient transfection with Smad‐2/‐4 or Smad‐3/‐4 expression vectors did not alter cell phenotype. Previously, we have demonstrated β‐catenin translocation to PTC nuclei and its association with Smad proteins following addition of TGF‐β1, suggesting the possibility that TGF‐β1 may modulate Wnt signalling. Wnt‐responsive Xtwn‐reporter construct was, however, silent in response to TGF‐β1. Similarly, a second Wnt‐/LEF‐1‐regulated element Toplflash, which does not contain Smad‐binding sites, was insensitive to TGF‐β1 signalling. In contrast, phenotypic changes in response to TGF‐β1 were abrogated by inhibitors of the RhoA downstream target ROCK, which also prevented loss of cell–cell contact and adherens junction disassembly. Removal of TGF‐β1 and addition of 1% FCS, however, reverted cell phenotype to a typical cobblestone epitheliod appearance, suggesting that TGF‐β1 did not result in terminal PTC transdifferentiation. Cells grown on tissue culture dishes coated with either type‐I or type‐III collagen also acquired an elongated fibroblastic phenotype; this effect was exaggerated by the addition of TGF‐β1. In contrast to the cells stimulated with TGF‐β1 alone, following stimulation by both TGF‐β1 and exposure to interstitial collagens, cell phenotype was stable in that it was not reversed upon removal of TGF‐β1 and addition of FCS. Addition of TGF‐β1 to cells grown on type‐IV collagen had no greater effect than TGF‐β1 alone. Addition of TGF‐β1 alone had little effect on the expression of α‐SMA. In contrast, cells grown on either type‐I or type‐III collagen, following addition of TGF‐β1, demonstrated marked increased expression of α‐SMA, which appeared to be incorporated into the cell cytoskeleton. Similarly, the combination of interstitial collagen (either type‐I or type‐III) and TGF‐β1 had synergistic effect on the relocation and down‐regulation of the epithelial markers E‐cadherin and cytokeratin. Finally, the results demonstrated synergistic effects of coating with interstitial collagen (either type‐I or type‐III), on cell ‘fibroblastic’ cell function as assessed by cell migration and by the synthesis of type‐III and type‐IV collagen. Conclusion The results of these in vitro experiments suggest that terminal transdifferentiation of proximal tubular epithelial cells is the result of a combination of the effects of the pro‐fibrotic cytokine TGF‐β1 and exposure of the cells to components of the interstitial extra‐cellular matrix to which the cells are not exposed in the absence of damage to the tubular basement membrane. 相似文献
47.
心理支持疗法对机械通气患者应激反应的影响 总被引:2,自引:1,他引:1
目的 观察心理支持疗法(PST)对ICU患者机械通气应激反应的影响。方法 将34例连续机械通气时间在20h的清醒患者,随机分为采用标准的PST方法进行治疗的观察组和对照组,观察焦虑抑郁程度和应激反应改变情况。结果 对照组患者的焦虑抑郁程度明显高于观察组,部分应激反应激素水平升高幅度也明显大于观察组。结论 PST可通过缓解机械通气患者的焦虑抑郁等不良情绪状态减轻机械通气带来的各种心身应激反应,有利于提高机械通气治疗的有效性和安全性。 相似文献
48.
Chuan-ling Qiao Kang-zhen Yu Yong-ping Jiang Yong-qing Jia Guo-bin Tian Ming Liu 《Avian pathology》2003,32(1):25-31
Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI. 相似文献
49.
Dong-Hai Xiong Hui Shen Peng Xiao Yan-Fang Guo Ji-Rong Long Lan-Juan Zhao Yao-Zhong Liu Hong-Yi Deng Jin-Long Li Robert R Recker Hong-Wen Deng 《Journal of bone and mineral research》2006,21(3):424-437
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures. 相似文献
50.
背景与目的:功能性消化不良(FD)被认为是一类由不同病理生理原因导致的多种机能紊乱而促发的症状。Rome Ⅱ委员会建议将具有同种病理生理学及临床特征的FD患划分为感觉明显疼痛组和感觉不适组两个亚组。该研究旨在分析显疼痛或感觉不适与病理生理学机制间的关系,评价是否考虑到个体的显性症状将会产生更好的结果。方法:持续性FD患(n=720;489例女性;年龄41.3±0.6岁)填写消化不良调查问卷并确定出最令人烦恼的症状。分析此显症状在人口统计学、临床、病理生理学特点上的相互联系(研究592例患幽门螺杆菌感染、胃排空情况,对332例患行胃敏感性、顺应性试验)。结果:根据Rome Ⅱ标准,22%疼痛明显,78%不适感明显。疼痛明显的患超敏性的发生率较高(44% vs 25%),且在这些病例中观察到的胃排空迟缓较少出现(16% vs 26%),但是有较多的重叠。详细分析表明可能有8种消化不良症状其中之一较为突出。 相似文献