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排序方式: 共有5063条查询结果,搜索用时 187 毫秒
21.
Iodine-125 interstitial irradiation for cerebral gliomas 总被引:3,自引:0,他引:3
22.
E. Eric Muirhead David H. P. Streeten Bennie Brooks Edward T. Schroeder Lawrence W. Byers 《Blood pressure》1992,1(3):138-148
A new syndrome is described in a patient with advanced renal insufficiency. This consists of severe and persistent hypotension causing weakness but associated with a clear mental status. Also present is evidence for decreased vascular reactivity. The hypotension was not orthostatic. The hypotension was associated with a circulating vasodepressor substance having the characteristics of medullipin I. The medullipin appears to have been derived from the remaining right kidney. Hypotension existed despite the presence of major prohypertensive mechanisms, including an endstage kidney, hyperreninemia and hyperaldosteronemia. It is likely that hypotension due to hypermedullipinemia is an entity occurring in the human being. 相似文献
23.
Sandra Lobo Jaroslav Cervenka Arnold London Mary Ella M. Pierpont 《American journal of medical genetics. Part A》1992,43(4):701-703
We report on a patient with interstitial deletion of 10q and compare her to 8 previously described patients, 2 of whom have chromosomal breakpoints similar to our patient. Minor anomalies including broad forehead, hypertelorism, strabismus, prominent philtrum, and “dysplastic” pinnae are present in our patient. Psychomotor retardation and hypotonia are universal findings in 10q interstitial deletion. Growth retardation, not present in our patient, is seen in some. These clinical findings are sufficiently distinct to suggest early chromosome studies. © 1992 Wiley-Liss, Inc. 相似文献
24.
目的:探讨单侧输尿管梗阻后大鼠肾间质纤维化发生过程中肝细胞生长因子(HGF)的表达及中药参附注射液对其的影响。方法:采用单侧输尿管结扎(UUO)制造梗阻性肾病模型,将56只大鼠随机分为对照组(假手术组)、手术组(UUO组)和治疗组(UUO+参附),术后7d、14d观察肾组织病理改变,应用免疫组织化学方法检测肾组织中HGF的表达。结果:与对照组相比,手术组肾间质出现了明显的纤维化,HGF的表达在术后第7天明显增加,第14天较第7天减弱,与手术组相比,治疗组肾间质纤维化明显减轻,而且HGF的表达在术后第7天明显上调,第14天较第7天上调更明显,有统计学差异(P〈0.05)。结论:参附注射液可以上调肾组织HGF的表达,减轻肾小管一间质纤维化,发挥肾保护作用。 相似文献
25.
26.
转化生长因子-β和碱性成纤维细胞因子在儿童原发性局灶节段性肾小球硬化肾组织中的表达 总被引:1,自引:1,他引:0
目的:通过检测转化生长因子-β(TGF-β)和碱性成纤维细胞生长因子(bFGF)在儿童原发性局灶节段性肾小球硬化(FSGS)肾组织中的表达情况,并分析其与肾小管间质病理变化的关系,以了解TGF-β与bFGF在原发性FSGS发生发展中的作用。方法:选择肾活检明确诊断为原发性FSGS患儿的肾组织共43例,其中不伴有肾小管间质病变的FSGS肾组织共16例,设为实验1组;伴有肾小管间质病变的FSGS肾组织共27例,为实验2组。另将同期因孤立性血尿入院肾活检证实为非FSGS、病理改变较轻的肾组织作为对照组,共17例。采用免疫组化法检测细胞/生长因子TGF-β、bFGF在各组中的表达。通过方差分析(ANOVA)和相关分析法分析细胞/生长因子的表达与FSGS肾组织病理变化的关系以及细胞/生长因子之间的相互作用关系。结果:TGF-β、bFGF在各组肾组织中均有表达,表达量在对照组、实验1组和实验2组中依次升高,各组间的差异均具有统计学意义(P〈0.05);且TGF-β和bFGF的表达与肾小管间质指数呈正相关,相关系数依次为0.763和0.661。此外,TGF-β和bFGF两者的表达量经相关分析也显示呈正相关,相关系数为0.587。结论:TGF-β和bFGF在原发性FSGS患儿肾组织中高表达;随着FSGS的发展,它们在肾组织中表达量不断增加,促使肾小管间质向纤维化发展,而且两者在促进肾脏纤维化具有一定的协同作用。 相似文献
27.
Zhen-yu Wu Laurent P. Rivory Michael S. Roberts 《Journal of pharmacokinetics and pharmacodynamics》1993,21(6):653-688
Distribution of Evans Blue (EB), sucrose, and water into the isolated perfused rat hindlimb was studied under various conditions using the multiple indicator dilution (MID) technique. Statistical moment analyses of the outflow profiles for the EB, sucrose, and water were used to define the vascular, extravascular, and total water spaces, respectively. The varied perfusion conditions included albumin content (2, 4.7, and 7%), temperature (25, 37, and 42 C), perfusate flow rate (2, 4, 8, and 12 ml/min) and the presence/absence of red blood cells. The range of studies undertaken were chosen to represent the variety of conditions used in the preparation of both isolated animal and human limbs, the latter being particularly important in cytotoxic therapy for recurrent malignant melanoma. The distribution volumes of EB, sucrose, and water were dependent on the flow rate and the albumin content of perfusate. The normalized variances (CV
2
) of the markers were of the following order: sucrose (2.18) > water (1.58) > EB (0.68), indicating that some disequilibrium occurs during the capillary exchange of water and sucrose. It is suggested that a Krebs-Henseleit buffer containing 2% BSA is a suitable perfusate for most studies of the isolated rat hindlimb perfusion. The effect of albumin concentration manifests itself only at higher flows.We acknowledge the support of the National Heart Foundation (Queensland) and the Mayne Bequest Foundation. This study was conducted while the investigator (Z.Y. Wu) was in receipt of a WHO Research Training Grant. Professor M. S. Roberts also acknowledges the support of the Queensland and Northern New South Wales Lions Kidney & Medical Research Foundation. 相似文献
28.
Giuseppe D'AMICO 《Nephrology (Carlton, Vic.)》1997,3(1):13-17
Summary: IgAN is the commonest primary glomerulonephritis in all parts of the world; the different incidence reported in different geographical areas is mainly due to different biopsy policies, even though genetic factors, still unclarified, may be acting. Progression to ESRF occurs in IgAN at a variable rate (average renal survival at 10 years is 80–87%), and many studies, reviewed in this paper, have sought to identify clinical and histological features which are predictive of the outcome. A functional impairment at presentation and a severe proteinuria are the most powerful clinical indicators of unfavourable prognosis, while both glomerular and interstitial sclerosis are the most reliable histological indicators. The fact that these prognostic indicators are not always reliable in predicting the outcome for a single patient, probably due to the pathophysiology of the progressive damage in this disease, is stressed. 相似文献
29.
P. MORSING A. STENBERG D. CASELLAS A. MIMRAN C. MÜLLER-SUUR C. THORUP L. HOLM A. E. G. PERSSON 《Acta physiologica (Oxford, England)》1992,146(3):393-398
Atrial natriuretic peptide (ANP), injected at physiological concentrations, is known to induce both natriuresis and diuresis. It has been suggested by some investigators that these changes result from an increasing glomerular filtration rate (GFR), but others have been unable to demonstrate an increased GFR. The tubuloglomerular feedback (TGF) mechanism is an important regulator of GFR, and the sensitivity of TGF is decreased during ANP administration. Furthermore, resetting of TGF is, in most instances, related to changes in renal interstitial hydrostatic and oncotic pressures. It is also known that ANP may increase capillary permeability which may change renal interstitial pressure. The present study was performed to examine renal interstitial pressures and the TGF mechanism during ANP infusion. In accordance with previous studies, TGF sensitivity was found to be decreased. The tubular flow rate which elicited half the maximal drop in stop-flow pressure (Psf) was increased from 18.5 to 25.7 nl min-1. In contrast, ANP infusion resulted in a decreased interstitial hydrostatic pressure and an increased interstitial oncotic pressure. From previous experiments, such changes in interstitial pressures would be expected to increase TGF sensitivity. The changes in interstitial pressure cannot, therefore, directly explain the resetting of the feedback mechanism. In conclusion, the present paper shows a decreased renal net interstial pressure after intravenous administration of ANP. 相似文献
30.
Currently, there is debate in the clinical literature as to whether defects in vertical gaze are a consequence of normal ageing or a component of an underlying neurodegenerative disorder. Although pathological changes have been demonstrated in diseased subjects, no study to date has addressed the question of normal ageing effects. In this retrospective study, we examined 23 neurologically and pathologically normal subjects (age 18-91). Using an unbiased, frame-based sampling method, we quantified neuronal and glial cell densities in 10 young (<50) and 13 aged (>65) subjects in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), the key premotor substrate in the vertical gaze pathway. We found no statistically significant difference in neuronal density, glial cell density, or neuron-to-glial cell ratios between the young and the aged. We conclude, therefore, that neuronal loss, neuronal atrophy, or gliosis in the riMLF are not consequences of normal ageing. 相似文献