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101.
Renal allograft loss from chronic rejection or cyclosporine toxicity (CsAT) is characterized by progressive interstitial fibrosis, yet the protein composition of these lesions is unknown. The normal tubular basement membrane (TBM) contains laminin (LM), collagen IV (containing collagen IV alpha chain 1 [COL4A1] and COL4A2), thrombospondin (TSP), and fibronectin (FN). Only TSP and FN extend beyond the TBM into the interstitial space. Very scanty amounts of interstitial collagens (I and III) are detected in the interstitium. In a pilot study of human renal allograft biopsy specimens, three patterns of extracellular matrix (ECM) composition were identified. Pattern 1 showed no change in ECM composition; pattern 2 showed generalized accumulation of collagens I and III in the interstitium; and pattern 3 showed new expression of COL4A3 and LM-beta2 in the proximal TBM. Criteria were established for the clinicopathological diagnosis of CsAT and rejection. These diagnoses were correlated with the ECM composition in 22 renal allograft biopsy specimens. Control groups were examined in a similar manner and included native kidney biopsy specimens from patients with other allografts (n = 7), renal biopsy specimens from patients with glomerular disease (n = 9), and renal allograft biopsy specimens from patients without clinicopathological evidence of renal disease. These data show that rejection is associated with pattern 3 and CsAT is associated with pattern 2. Thus, detection of ECM composition may be a useful adjunct to standard microscopy in distinguishing rejection from CsAT in renal allograft biopsy specimens. These data suggest that interstitial fibrosis associated with rejection and CsAT result from different pathogenic mechanisms.  相似文献   
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立位X线胸片可敏感而特异地显示膈下游离气体 ,对开放性结肠直肠切除术后空腔脏器出现破损是一项有效的检查 ,但由于剖腹术后气腹自然吸收所需要的时间未知 ,其作用尚未被确定。本次试验的目的即在于确定这一时间。   3个月内连续 92例接受了连续性结肠直肠切除术的病人 (8例拒绝合作 ,9例采用了腹腔镜技术 )中的 75例参与了这次试验 (平均年龄 6 2 1岁 ,男∶女 =1 3∶1) ,手术指征分别为直肠癌 6例 ,憩室病 2例 ,肠道炎症 2例 ,放疗引起狭窄 3例 ,功能性疾患 (慢性运输性便秘 ,直肠脱垂 ) 2例 ,其它 (家族性腺瘤息肉、乙状结肠扭转、短…  相似文献   
103.
树突状细胞与肝脏疾病   总被引:9,自引:3,他引:6  
免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6].  相似文献   
104.
Computed tomography (CT) is a valuable tool in the workup of patients under investigation for pulmonary hypertension (PH) and may be the first test to suggest the diagnosis. CT parenchymal lung changes can help to differentiate the aetiology of PH. CT can demonstrate interstitial lung disease, emphysema associated with chronic obstructive pulmonary disease, features of left heart failure (including interstitial oedema), and changes secondary to miscellaneous conditions such as sarcoidosis. CT also demonstrates parenchymal changes secondary to chronic thromboembolic disease and venous diseases such as pulmonary venous occlusive disease (PVOD) and pulmonary capillary haemangiomatosis (PCH). It is important for the radiologist to be aware of the various manifestations of PH in the lung, to help facilitate an accurate and timely diagnosis. This pictorial review illustrates the parenchymal lung changes that can be seen in the various conditions causing PH.  相似文献   
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AIM: To evaluate the effectiveness and safety of acupuncture for the treatment of obesity by reviewing currently available randomised controlled trials. METHODS: This review followed the Cochrane Handbook for Systematic Reviews of Interventions. Fifteen English and three Chinese databases were searched from their respective inceptions until July 2014. Key words used in the search consisted of acupuncture, needles, obesity, overweight, randomised trial and their synonyms. The risk of bias of included studies was assessed. The differences in effect size between acupuncture and control (including sham, no treatment, western medicine and dietary therapy/exercise) groups were compared using Cochrane Collaboration’s RevMan 5.3 software. RESULTS: Two thousand six hundred and twenty-one records were identified; after full-text articles assessed for eligibility, 9 of them met inclusion criteria. Majority of included studies had unclear or high risk of bias across all domains. All included studies had high or unclear risk of bias in randomisation, blinding and outcome data. Meta-analysis showed that acupuncture was more effective for reducing body weight and body mass index than no treatment group. Manual acupuncture was also superior to dietary therapy alone for decreasing body weight. With dietary therapy as co-intervention, combined acupuncture group achieved lower body mass index than combined sham acupuncture group or dietary therapy alone group at the end of treatment period. No severe adverse events from acupuncture group were reported from all included studies. CONCLUSION: Due to the poor quality of included studies the effectiveness of acupuncture cannot be concluded. Better-designed, large-scale, randomised, sham-controlled clinical trials with long-term follow-up are needed.  相似文献   
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