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1.
Advanced diabetic glomerulopathy. Quantitative structural characterization of nonoccluded glomeruli 总被引:4,自引:0,他引:4
Quantitative ultrastructural data were obtained from kidney biopsy material of 12 long-term insulin-dependent diabetics. All patients had overt diabetic nephropathy with increased urinary albumin excretion and reduced glomerular filtration rate. Renal clearance of 51Cr-EDTA was in the range of 16-50 ml X min-1 X 1.73 m-2. All patients received antihypertensive treatment. A combined light- and electron-microscope study was performed. A significant proportion of the glomeruli was totally occluded (mean 36%, range 24-67%). Structural data presented relate only to the open, still-functioning glomeruli. Comparison with data previously obtained showed that the thickness of the peripheral basement membrane [647 nm, coefficient of variation (C.V.) 0.22] was more than twice the normal value (310 nm, C.V. 0.08); the width of epithelial foot processes (352 nm, C.V. 0.07) was significantly greater than in normal biopsies (224 nm, C.V. 0.06); and the mean volume of the open glomeruli was markedly increased compared with normal and clearly exceeded that in the early diabetic hypertrophy. Total mesangial volume and total basement membrane material per open glomerulus were increased by 277 and 614%, respectively. However, capillary length and surface per open glomerulus were similar to those observed in early diabetic hypertrophy. These findings suggest that a late glomerular hypertrophy with preservation of capillary surface occurs as a compensatory phenomenon, prolonging renal survival for diabetic nephropathy patients. 相似文献
2.
J. Åberg B. Abrahamsson M. Grind G. Nyberg B. Olofsson 《European journal of clinical pharmacology》1997,52(6):471-477
Objective: The primary aim of this study was to investigate whether bioequivalence is achieved for a new fixed combination of extended-release
(ER) felodipine and controlled-release (CR/ZOK) metoprolol␣compared with the free combination of felodipine ER metoprolol
CR/ZOK. The second aim was to study whether there was an interaction in pharmacokinetics and pharmacodynamics between felodipine
and metoprolol when administered as ER formulation.
Methods: Two four-way cross-over studies were performed in 36 young subjects and 24 elderly subjects with frequent measurement of
drug plasma concentrations, blood pressures and heart rate. The pharmacokinetic analysis included enantioselective analysis
in six subjects.
Results: Bioequivalence between the fixed combination and the free combination was observed for the two drugs (mean difference 27%)
except for a minor deviation regarding Cmax of metoprolol in the elderly. No significant interaction was shown except for a small increase (6%) of metoprolol AUC in
the younger subjects. Mean plasma S-/R-enantiomer ratios were almost identical for the different treatments. Blood pressure and heart rate was significantly reduced
for the fixed combination compared with felodipine ER in the younger and the elderly subjects. No significant difference regarding
pharmacodynamics was detected between the fixed combination and the corresponding free combination.
Conclusion: The fixed combination consistently provides fairly constant and effective felodipine and metoprolol concentrations after
once-daily administration of one tablet. It is clinically interchangeable with the free combination of metoprolol CR/ZOK tablets
and felodipine ER tablets. Finally, felodipine and metoprolol do not interact on a pharmacokinetic level when administered
as the fixed combination.
Received: 29 October 1996 / Accepted in revised form: 21 March 1997 相似文献
3.
The antiviral agent foscarnet has long been used in our unit to treat cytomegalovirus (CMV) infections in renal transplant
patients. The clinical effect has been convincing and, apart from changes in serum calcium levels, very few side effects have
been noted. We have, however, observed a nephrotoxic reaction in a series of patients with initially good renal function who
therefore received high doses of foscarnet. Transplant biopsies performed in five of those patients revealed degenerative
changes in the tubular epithelial cells as well as tubular calcium deposits and an infiltration of the interstitium by mixed
mononuclear and polymorphonuclear leucocytes. Renal insufficiency was accompanied by high fever. After withdrawal of the drug,
the temperature rapidly normalized, whereas serum creatinine continued to rise for about 3 days and then fell back towards
previous levels. We conclude that transplant biopsies are of great value in distinguishing between a foscarnet nephrotoxic
effect and CMV nephritis, various forms of rejection, and other causes of impaired renal function. 相似文献
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To compare the normal extrahepatic portion of the fetal intra-abdominal umbilical vein (FIUV) with varix of the FIUX, we prospectively measured the diameter of the FIUV in 150 uncomplicated second and third trimester pregnancies and compared these results with retrospective review of nine fetuses with varix of the FIUV as an isolated prenatal sonographic finding. The diameter of the normal FIUV increases linearly from approximately 3 mm at 15 menstrual weeks to approximately 8 mm at term (R = 0.92). The nine fetuses with FIUV varix had a FIUV diameter 6 to 12 standard deviations above the mean for age. Four (44%) of the nine fetuses with FIUV varix subsequently died, including one with trisomy 21. One of the remaining fetuses developed severe hydrops 2 weeks after the initial detection of the FIUV varix. FIUV varix appears to carry an increased risk of adverse fetal outcome, including fetal demise. 相似文献
7.
Scott L. Nyberg Arthur J. Matas Walter K. Kremers Jeffrey D. Thostenson Timothy S. Larson Mikel Prieto Michael B. Ishitani Sylvester Sterioff Mark D. Stegall 《American journal of transplantation》2003,3(6):715-721
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation. 相似文献
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The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献