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81.
针刺对肾血管性高血压大鼠的降压效应   总被引:8,自引:0,他引:8  
目的 探讨针刺对肾血管性高血压大鼠的降压作用及其神经 -内分泌调节机制。方法 采用二肾一夹法制备高血压大鼠模型 ,测定实验各组大鼠血浆内皮素 (ET)、一氧化氮 (NO)含量和心率变异性 (HRV)的动态变化。结果 与模型组相比 ,针刺组血压 (BL 2 3:19.1± 1.1k Pa,ST36:18.1± 2 .5 k Pa)及 ET水平明显下降 (P<0 .0 1) ,其中针刺肾俞组血浆 ET水平 (91.3± 9.45 pg/ ml)较足三里组 (10 8.48± 13.0 6pg/ ml)下降更明显 (P<0 .0 5 ) ;针刺治疗组血浆 NO水平 (BL 2 3:5 0 .3±12 .7μmol/ ml,ST 36:49.71± 8.49μm ol/ m l)显著升高 (P<0 .0 5 )。足三里组针刺后 L F/ HF比值与模型组无明显差异 ,而肾俞组 L F/ HF值 (0 .5 7± 0 .13)明显低于模型组及足三里组 (0 .86± 0 .2 5 )。结论 针刺能降低肾血管性高血压模型大鼠动脉血压 ,肾俞与足三里两穴无明显差异 ,其作用机制可能与自主神经系统、NO及 ET参与的神经内分泌调节作用相关。  相似文献   
82.
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.  相似文献   
83.
川芎嗪对肾缺血再灌注时c-fos bcl-2 ICAM-1蛋白表达的影响   总被引:1,自引:0,他引:1  
目的 探讨大鼠肾缺血再灌注损伤不同时间c -fos、细胞淋巴瘤 /白血病 - 2、细胞间粘附分子- 1蛋白的表达及川芎嗪对其影响。方法 用免疫组化法检测大鼠急性肾缺血再灌注不同时间内及川芎嗪干预后c -fos、细胞淋巴瘤 /白血病 - 2、细胞间粘附分子 - 1蛋白表达的分布及强度变化。结果 c -fos蛋白分布于近曲小管、远曲小管、集合管上皮细胞的细胞核、细胞浆内 ,再灌注后 1h表达明显增强 ,3h达高峰 ,6h锐减。细胞淋巴瘤 /白血病 - 2蛋白主要分布于近曲小管上皮细胞的细胞浆 ,再灌注后 1h表达明显增强 ,6h达高峰 ,2 4h仍有较强表达。细胞间粘附分子 - 1蛋白分布在肾血管、肾小管等部位 ,其中以肾血管为著 ,其表达增强于再灌注后 1h ,直到 2 4h仍有增高趋势。川芎嗪干预后c -fos、细胞间粘附分子 - 1蛋白表达明显下降 (P <0 0 1 )。细胞淋巴瘤 /白血病 - 2表达明显增高 (P <0 .0 1 )。结论 川芎嗪对肾缺血再灌注损伤有较好的保护作用  相似文献   
84.
肠易激综合征(IBS)是一组持续存在或反复发作的临床症候群,主要症状有腹痛、腹胀、排便习惯改变和大便性状异常、黏液便等,经检查排除可引起这些症状的器质性疾病。临床分为肝木乘脾型腹泻、脾胃虚弱型腹泻、脾肾阳虚型腹泻、肝郁脾虚型便秘四型,根据临床辨证分别施以不同治法,不同方药治疗,有显著疗效。同时,教育患者平时养成良好的饮食卫生习惯,不饮生水,不食生冷瓜果,忌食辛辣、油腻、肥厚之品,保持心情舒畅,怡情悦志,注意保暖,可加强疗效,防止复发。  相似文献   
85.
Tacrolimus has a narrow therapeutic window and is characterized by a large inter-individual variability in bioavailability. The impact of tacrolimus exposure on subclinical evolution of graft histology has not been studied in renal recipients. This analysis included 239 protocol biopsies (obtained at implantation, 3 and 12 months) of 120 consecutive kidney recipients treated with tacrolimus, mycophenolate mofetil (MMF) and corticosteroids. Biopsies were scored according to the Banff 2001 criteria and a chronicity score was calculated. Prospective pharmacokinetic data were included in the analysis (5544 tacrolimus predose blood concentrations and tacrolimus AUC(0-12) at 3 and 12 months). Higher donor age and higher number of human leukocyte antigen-DR (HLA-DR) mismatches were independent predictors of subclinical acute rejection at 3 months, present in 8.7% of patients. The number of HLA-DR mismatches was independently associated with biopsy-proven clinical acute rejection. Biopsy-proven acute rejection episodes and low mean tacrolimus exposure were independently associated with higher increase in chronicity scores between 3 and 12 months after transplantation. This observational study suggests that rejection phenomena and immune-mediated mechanisms remain important in the early progression of chronic allograft pathology. Tacrolimus doses or systemic exposure were not associated with lesions of calcineurin inhibitor nephrotoxicity, suggesting that other factors determine susceptibility to tacrolimus nephrotoxicity.  相似文献   
86.
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration.  相似文献   
87.
BACKGROUND: Microalbuminuria and macroalbuminuria constitute risk factors for ESRD and death in non-transplanted populations. Whether microalbuminuria (especially in non-proteinuric patients) and macroalbuminuria constitute risk factors for graft loss and death is presently unknown in renal transplantation. METHODS: We retrospectively assessed the association between urinary albumin excretion (UAE) and ESRD and death in renal transplantation. RESULTS: UAE was measured in 616 (397 proteinuric; 219 non-proteinuric patients) renal transplant recipients. They were grafted for 62 months (range: 6-192). During the 40 months (3.7-99) thereafter, 31 patients underwent dialysis and 32 died. Microalbuminuria (vs. normoalbuminuria) and macroalbuminuria (vs. microalbuminuria) were powerful risk factors for graft loss [OR: 14.25 (2.88-52.3) and 16.41 (7.46-36.0), respectively, both p < 0.0001], even after adjustments on renal function and diabetes. Among the 219 non-proteinuric patients, microalbuminuria (vs. normoalbuminuria) was a significant risk factor for graft loss [OR: 23.09 (1.93-276.4), p = 0.0132]. Both microalbuminuria (vs. normoalbuminuria) [OR: 5.55 (2.43-12.66), p < 0.0001] and macroalbuminuria (vs. microalbuminuria) [OR: 4.12 (1.65-10.29), p = 0.0024] were predictive of death. CONCLUSIONS: Microalbuminuria and macroalbuminuria are powerful independent predictors of ESRD and death. Microalbuminuria is a risk factor for graft loss even in non-proteinuric patients. UAE provides additional information on renal and patient prognosis as compared to proteinuria and renal function.  相似文献   
88.
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity.  相似文献   
89.
Different immunosuppressant regimens vary in their effects on antibody responses to vaccination. The combination of prednisolone and azathioprine has only a minor effect, whereas the addition of ciclosporin attenuates protective antibody responses to influenza vaccination. The effect of sirolimus, a new immunosuppressant, on vaccine responses has been little studied. Thirty-two hepatic or renal transplant patients randomized to calcineurin inhibitor-based or sirolimus-based immunosuppression were vaccinated against influenza and pneumococcus. Following tri-valent influenza vaccination, a similar rise in antibody titer occurred in sirolimus and calcineurin inhibitor (CNI) treated patients, though sirolimus treated patients developed a 'protective' titer to more influenza antigens. The pneumococcal polysaccharide vaccine was equally effective in both groups. Hence, vaccination guidelines in place for CNI treated patients are likely to be appropriate for transplant recipients maintained on sirolimus.  相似文献   
90.
邻近皮瓣修复面部皮肤缺损   总被引:1,自引:0,他引:1  
目的 探讨邻近皮瓣修复面部皮肤缺损的应用效果。方法 162例面部病变切除后皮肤缺损患者,其中先天性色素痣63例,基底细胞癌28例,鳞状细胞癌6例,其他皮肤病变65例。均采用邻近皮瓣即时修复,其中菱形皮瓣57例、双叶皮瓣8例,A-T皮瓣23例、V-Y皮瓣13例、Z成形术23例、推进皮瓣27例、鼻状皮瓣11例。结果 162例皮瓣存活良好,手术切口1期愈合,存活后皮瓣颜色与邻近部位无明显差异,术后无眼睑、眉毛、鼻梁及口角牵扯歪钭,术后3个月切口不显露。结论 邻近皮瓣是修复面部较大皮肤缺损的良好方法,手术外观效果好。  相似文献   
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