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41.
Atubular glomeruli in patients with chronic pyelonephritis   总被引:2,自引:0,他引:2  
In an animal model of chronic nephropathy a large proportion of the apparently normal glomeruli have been shown to be small and without connection to a proximal tubule. The present study examines the degree to which atubular glomeruli are also present in human renal disease. Eleven patients with chronic pyelonephritis (CP) and seven controls were investigated. The number of glomeruli connected to a normal proximal tubule was determined in serial sections and the volumes of individual glomeruli estimated with stereological methods. Only glomeruli with little or no sclerosis were investigated. The volume fractions of proximal tubules and interstitial tissue were estimated using point counting. The results showed that 50% of glomeruli in the CP group were connected to a normal proximal tubule, whereas 35% of the glomeruli were without any recognizable connection to a proximal tubule (atubular glomeruli). The remaining 15% were connected to an atrophic tubule. The mean volume of the glomeruli without a connection to a normal proximal tubule was only half that of glomeruli with a normal proximal tubule. No significant difference was found between the mean glomerular volume in the two groups, but the intraindividual variation of glomerular volumes was larger in the CP group. A significant negative correlation was found in the CP group between the percentage of glomeruli without connection to a normal proximal tubule and the volume fraction of proximal tubules. A significant positive correlation was found between the percentage of glomeruli that were not connected to a normal proximal tubule and the volume fraction of the interstitial tissue. This study shows that atubular glomeruli, which only can be identified in serial sections, constitute a large proportion of glomeruli in chronic pyelonephritis. Their existence could be a major reason for the irreversibility of nonglomerular chronic renal diseases.  相似文献   
42.
Regional cerebral blood flow after occlusion of the middle cerebral artery   总被引:3,自引:0,他引:3  
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs  相似文献   
48.
In this paper a doctor acts as a perfect agent for a group of patients in an environment where the health service is funded by a group of contributors. The contributor group donates resources to the health sector in accordance with its split preferences about the health care services which they would like for themselves and those which they would like for others. We show that the size of the health budget is endogenous and depends on the choices made by the doctor. The focus is on the division of the budget between health enhancing and non-health enhancing health care.  相似文献   
49.
Rapid slide culture method using human blood medium was utilized for the primary culture of Mycobacterium tuberculosis and the results obtained were compared with results of smear examination of sputum specimens from fresh cases of pulmonary tuberculosis. Smear and rapid slide culture results of a total of 320 patients were analyzed. Slide culture was positive in 104 cases whereas smears were positive in 90 cases. Early culture confirmation in 7 days coupled with positivity better than smear examination, makes rapid slide culture a better method for diagnosis.KEY WORDS: Mycobacterium tuberculosis, Rapid slide culture, Bacteriological techniques, Colony count microbial  相似文献   
50.
Identification of sentinel lymph nodes (SLNs) using lymphoscintigraphy, the blue dye technique and intraoperative lymphatic mapping with a gamma-detecting probe has become the standard of care in diagnosing and treating melanoma. Numerous clinical studies have proven the reliability of predicting the histology of remaining lymph nodes in the lymphatic basin from the histologic evaluation of the SLNs. Technical and clinical factors presented in this paper have been shown to increase the accuracy of localization of SLNs. The nuclear medicine technologist shares a vital role in the radiopharmaceutical preparation and administration for preoperative lymphoscintigraphy and intraoperative lymphatic mapping in patients with melanoma.  相似文献   
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