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101.
Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.  相似文献   
102.
The gastric vasculature responsible for intraoperative bleeding in endosocpic submucosal dissection (ESD) is the ramified vascular network occupying the middle of the submucosal layer and large vessels penetrating the muscle layer. Appropriate management for these vessels must be addressed. The trimming of the ramified vascular network can be safely performed with coagulation mode following shallow mucosal cutting. A large penetrating vessel usually requires precoagulation prior to dissection. These procedures are effectively performed with the water jet short needle knife (Flush knife).  相似文献   
103.
OBJECTIVE: To evaluate the effectiveness of a new method of using Independent Component Analysis (ICA) and k-means clustering to increase the signal-to-noise ratio of Event-Related Potential (ERP) measurements while permitting standard statistical comparisons to be made despite the inter-subject variations characteristic of ICA. METHODS: Per-subject ICA results were used to create a channel pool, with unequal weights, that could be applied consistently across subjects. Signals derived from this and other pooling schemes, and from unpooled electrodes, were subjected to identical statistical analysis of the N170 own-face effect in a Joe/No Joe face recognition paradigm wherein participants monitored for a target face (Joe) presented amongst other unfamiliar faces and their own face. Results between the Joe, unfamiliar face and own face conditions were compared using Cohen's d statistic (square root of signal-to-noise ratio) to measure effect size. RESULTS: When the own-face condition was compared to the Joe and unfamiliar-face conditions, the channel map method increased effect size by a factor ranging from 1.2 to 2.2. These results stand in contrast to previous findings, where conventional pooling schemes failed to reveal an N170 effect to the own-face stimulus (Tanaka JW, Curran T, Porterfield A, Collins D. The activation of pre-existing and acquired face representations: the N250 ERP as an index of face familiarity. J Cogn Neurosci 2006;18:1488-97). Consistent with conventional pooling schemes, the channel map approach showed no reliable differences between the Joe and Unfamiliar face conditions, yielding a decrease in effect size ranging from 0.13 to 0.75. CONCLUSIONS: By increasing the signal-to-noise ratio in the measured waveforms, the channel pool method demonstrated an enhanced sensitivity to the neurophysiological response to own-face relative to other faces. SIGNIFICANCE: By overcoming the characteristic inter-subject variations of ICA, this work allows classic ERP analysis methods to exploit the improved signal-to-noise ratio obtainable with ICA.  相似文献   
104.
The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment.  相似文献   
105.
支气管扩张症辨证模式初探   总被引:4,自引:0,他引:4  
目的:探讨支气管扩张症的中医辨证分型规律及证候特点.方法:通过对563例支气管扩张症的临床流行病学调查,采集以症状、体征、舌、脉及相关理化检测为变量的基本信息,以频数分析、聚类分析、方差分析等方法,提炼支气管扩张症的证候分布规律及证候特点.结果:临床上支气管扩张症多见4种证候类型,分别为痰热壅肺证(45.65%)、肝火犯肺证(24.51%)、肺脾气虚证(22.38%)、气阴两虚证(7.46%).结论:较大样本的临床流行病学调查为研究支气管扩张症辨证分型规律提供了科学依据,并可以通过主症判别分析法建立证候识别模式,为临床实践提供依据.  相似文献   
106.
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.  相似文献   
107.
Objective   This randomized control trial examined the effects of a short-term, interaction-focused and attachment-based video-feedback intervention (VIPP: video-feedback intervention to promote positive parenting).
Design   VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n  = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods   Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results   We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d  = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion   We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants.  相似文献   
108.
枕骨大孔区腹侧脑膜瘤的显微手术技术探讨   总被引:1,自引:0,他引:1  
目的探讨远外侧入路在治疗枕骨大孔区腹侧脑膜瘤中的应用。方法对14例脑膜瘤患者采用远外侧入路显微手术治疗,其中枕髁后入路8例,经部分枕髁入路3例,经C1、2关节面侧方联合部分枕髁入路2例,经完整枕髁入路1例。结果肿瘤全切11例,次全切除3例;1例行枕颈融合,无手术死亡病例。所有患者术后均未出现寰枕关节不稳定的症状,手术并发症主要是后组颅神经损伤、椎动脉损伤、脑脊液漏以及脑干缺血。结论远外侧入路是手术治疗下斜坡区和上段颈髓腹侧、腹外侧病变的理想入路,可以理想显露肿瘤及其基底部并减少术中出血,但手术操作比较复杂且具有一定的风险。  相似文献   
109.
Despite the fact that both H-2K and D molecules are up-regulated in the central nervous system (CNS) following Theiler's murine encephalomyelitis virus (TMEV) infection, resistance in this virus model of multiple sclerosis maps exclusively to D. To address this paradox, we examined the ability of the K and D molecules to present viral antigens to cytotoxic T lymphocytes (CTL). Whereas no virus-specific CTL were detected in the CNS of susceptible B10.Q and B10.S mice 7 days post-infection, D-restricted CTL were identified readily in the CNS of resistant B10 animals. There was no evidence of K-restricted CTL in the CNS of B10 mice at day 7 post-infection. The presence of both K- and D-restricted virus-specific CTL in the spleen of immunized B10 mice demonstrates that the exclusive use of D molecules by CTL in the CNS of mice 7 days post-infection is not due to the inability of the K molecules to present viral peptides to lymphocytes. We conclude that the prominent role of the D locus in determining resistance or susceptibility to TMEV-induced demyelination is determined by factors governing the regulation of the immune response, and not by the presence or absence of CTL precursors capable of recognizing viral peptides presented by the K and D antigen-presenting molecules, or by differences in the ability of the K and D molecules to present viral peptides.  相似文献   
110.
Abstract. A single dose of rabbit antithymocyte globulin (ATG) was given as the sole immunosuppressive therapy in a model of strong MHC barrier rat heart allotransplantation. PVG/c hearts transplanted to Wistar/Kyoto (WKy) rats resulted in long-term surviving (LTS) grafts and cell-mediated lympholysis (CML) unresponsiveness in 50% of the animals. The effects of ATG treatment on the peripheral blood lymphocyte subsets were studied by flow cytometry. The absolute T-lymphocyte levels decreased to less than 5% and were normalized after 2 weeks. CD8-positive cells were normalized within 1 week, whereas CD4-and CD5-positive cells remained low. Rats with LTS grafts had low levels of all T-lymphocyte markers, especially the CD4-and CD5-positive cells. Rats rejecting their grafts showed an eightfold increase in levels of CD8-and CD5-positive lymphocytes and a twofold increase in levels of CD4-expressing lymphocytes. It is concluded that ATG treatment causes the immediate elimination of large lymphoid populations as well as long-lasting immunomodulation detectable in peripheral blood.  相似文献   
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