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161.
162.
Abstract:  Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N  = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria.  相似文献   
163.
BACKGROUND: Studies have reported an increase in median Lipoprotein (Lp) (a) in patients with high molecular weight (HMW) apolipoprotein (apo) (a) isoforms and renal impairment. Some studies identify Lp (a) levels as a risk factor for vascular disease in renal failure whilst others have demonstrated an association with apo (a) isoform type and vascular disease. METHODS: A total of 239 patients at end-stage renal failure (ESRF) were studied prior to the initiation of dialysis. Blood was taken for Lp (a) levels and apo (a) isoforms. Clinical vascular disease (CVD) was assessed on the basis of clinical history and Rose questionnaire. The control group for Lp (a) levels consisted of 228 healthy volunteers. RESULTS: Despite a higher median Lp (a) level in those with HMW isoforms, 30% of patients had Lp (a) levels <10 mg/dl. Overall, 49% patients were identified as having CVD. Diabetes, smoking history and Lp (a) levels were significantly associated with CVD in logistic regression analysis, although when patients with low molecular weight (LMW) and HMW isoforms were analysed separately, Lp (a) levels were not significantly associated with CVD in those with LMW isoforms. The rates of CVD in those with HMW isoform and low Lp (a) levels were significantly lower than those with HMW isoforms and elevated Lp (a) levels, 34 vs 57% (P < 0.01). CONCLUSIONS: Although median Lp (a) levels in those patients at ESRF with HMW isoforms are higher than controls, in a third of such patients Lp (a) levels remain relatively low. These patients have lower rates of CVD than those with high levels of Lp (a).  相似文献   
164.
OBJECTIVE: To accurately measure blood loss during childbirth in a developing country. METHOD: The alkaline hematin technique was used to quantify blood lost during delivery and 24 h postpartum in 158 women in Pemba Island, Zanzibar. RESULT: Women were found to lose less blood during childbirth and 24 h postpartum than previously reported. Compared with laboratory values, nurse-midwives approximated blood loss accurately (mean difference, i.e., mean underestimation by nurse-midwives, 4.90 mL); however, their imprecision was greater for higher laboratory values. CONCLUSION: This study may prompt further investigation, as no comparable data exist for developing countries where maternal mortality is high and severe anemia prevalent.  相似文献   
165.
目的 建立两面针原植物中L-芝麻脂素和L-细辛脂素的测定方法,并测定两面针不同部位两者的含量。方法 采用高效液相色谱法(HPLC),色谱柱为HYPERSIL BDS C18,流动相为乙腈:水(50:50),检测波长287nm。结果 L-芝麻脂素和L-细辛脂素的平均回收率和相对标准差分别为100.13%、1.61%和101.24%、1.46%。结论 此法可用于两面针的质量控制。两面针原植物根部的被测成分含量最高。  相似文献   
166.
The cause of Alzheimer's disease is unknown. Several factors have been proposed including head trauma. At present, the link between head injury and a subsequent neurodegenerative process is largely circumstantial, except in the case of dementia pugilistica (punch drunk syndrome) found in boxers. Recent studies have shown that the brains of boxers with this syndrome contain large numbers of 'diffuse' beta-protein immunoreactive plaques. We supposed that this plaque type might be associated with trauma induced Alzheimer-like degeneration. In order to test this hypothesis we have re-investigated a previously reported case of post-traumatic premature Alzheimer's disease. Immunocytochemistry using antibodies to amyloid beta-protein revealed large numbers of 'diffuse' non-Congophilic plaques with little or no neuritic component. A similar preponderance of this plaque type is present in the brains of boxers with dementia pugilistica. Our observations support the idea of a trauma induced Alzheimer-like degenerative process and indicate that such a condition is associated with a marked preponderance of 'diffuse' plaques.  相似文献   
167.
168.
Background A recombinant form of the α2(IV)NC1 domain of type IV collagen has been shown to have potent anti-angiogenic activity although this peptide has not been studied in the context of proliferative retinopathies. In the current investigation we examined the potential for α2(IV)NC1 to regulate retinal microvascular endothelial cell function using a range of in vitro and in vivo assay systems. Materials and methods α2(IV)NC1 at concentrations between 0.1 and 1 μg/ml was added to retinal microvascular endothelial cells (RMECs) followed by assessment of cell attachment, proliferation and survival. This agent was also tested within a novel in vitro three-dimensional retinal angiogenesis assay and the number of angiogenic sprouts quantified. α2(IV)NC1 was also delivered intra-vitreally to mice with oxygen-induced proliferative retinopathy (OIR) and neovascularisation evaluated in comparison with vehicle-treated controls. Results RMECs treated with α2(IV)NC1 (0.1, 0.5 and 1 μg/ml) showed delayed attachment at 3 h post-seeding, although this deficit had been restored at the 6-h time point. BrdU assay of DNA replication revealed that confluent RMECs treated with α2(IV)NC1 showed no measurable response in comparison with vehicle-treated controls. By contrast, proliferation of sub-confluent RMECs was significantly reduced by α2(IV)NC1 at 0.5 μg/ml (P<0.01). α2(IV)NC1 also induced apoptosis in RMECs and inhibited angiogenesis of pre-existing retinal vascular networks in vitro (P<0.001). Intra-vitreal injection of α2(IV)NC1 in the OIR model significantly inhibited pre-retinal neovascularisation compared with vehicle-treated controls (P<0.001). Conclusion α2(IV)NC1 inhibits angiogenesis in the retinal microvasculature. This recombinant protein has potential for the treatment of neovascularisation in proliferative retinopathies. BioStratum Inc. did not sponsor this research in any way. None of the authors are paid consultants with this company.  相似文献   
169.
庆大霉素中毒性耳聋   总被引:1,自引:0,他引:1  
庆大霉素目前仍是主要的致聋抗生素,庆大霉素中毒性耳聋的发病机制包括自由基损伤学说、内耳微循环障碍学说、毛细胞线粒体功能失常学说、细胞凋亡等,并发现一些与耳聋相关的基因。聚DL-天冬氨酸(PAA)、表皮生长因子(EGF)表皮生长因子(EGF)、碱性成纤维细胞生长因子(bFGF)、神经营养凼子3(NT3)、高压氧等对庆大霉素的耳毒性有一定的拈抗作用。中医药丹参、天鼓冲剂、复聪片、耳聋左慈丸等也可减轻庆大霉素的耳毒性。庆大霉素中毒性耳聋基因治疗具有良好的前景。制造一种由病毒DNA序列和非病毒载体结构共同组成的复合型载体,也许是未来基因治疗载体得到完善、基因治疗得到突破性进展的着手点之一。  相似文献   
170.
用20只Wistar大鼠以PHA—L免疫组织化学顺行追踪技术研究了下丘脑室旁核及其邻近区域对脑室系统室管膜的传出联系。在脑室系统某些部位的室管膜层或其下方见有丰富的标记纤维并见许多膨结和终末膨突。这些纤维似乎参与形成室管膜上、下丛,构成脑—脑脊液神经体液回路的重要环节。  相似文献   
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