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61.
HIV-associated nephropathy (HIV-N) is considered a distinctive disease, the pathogenesis of which is still undefined. Direct virus-induced renal cell damage has been postulated. The numerous cytolytic ultrastructural changes and a few studies by immunoperoxidase support this hypothesis, but there has been no demonstration of virus by electron-microscopy (EM) or by tissue culture. In seven out of 12 cases with histological characteristics of HIV nephropathy, with proteinuria (five cases) or with nephrotic syndrome (two cases), we tested renal tissue for HIV antigens: core p18 and p25; envelope gp45 and gp110, by means of immunoperoxidase avidin-biotin complex monoclonal antibodies (MoAbs). Light-microscopy (LM) showed in five patients a focal and segmental glomerular sclerosis, and in two a mesangial hyperplasia with vacuolisation of visceral epithelium and protein inclusions. Electron-microscopy, performed in five of seven patients, showed several protein inclusions in podocyte cytoplasm, tubuloreticular inclusions in endothelial cell cytoplasm in all cases, nuclear degranulation of tubular cells in four cases and nuclear bodies in two. HIV antigens by MoAbs on renal tissue were negative in all cases, in both glomeruli and tubules. These results do not confirm the presence of HIV proteins in renal tissue of patients with HIV nephropathy. A possible explanation, apart from no direct HIV in the disease, may be the low viral load in tissues, because of the early phases of renal damage in most cases.  相似文献   
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The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited.  相似文献   
66.
A retrospective study of 232 bladder tumours with minimum follow-up 5 years is presented. The carcinoma was superficial in 66%, muscle-invasive in 31% and could not be staged in 3%. Primary treatment was mainly transurethral resection for superficial tumour, but was cystectomy or radiotherapy in 22 of 29 T1 G3. Of the superficial tumours, 71% recurred. Progression to higher T stage occurred in 15% of Ta and 29% of T1 tumours, and half of these patients died of bladder cancer. The corrected 5-year survival rates in grades 1, 2A, 2B and 3-4 were 96, 84, 64 and 43%, and in stages Ta, T1, T2 and T3 they were 94, 69, 40 and 31%. All patients with T4 tumour died within 4 years. Among the 45 patients with 40 Gy irradiation + cystectomy, the corrected 5-year survival rate was 83% in superficial and 64% in muscle-invasive tumours, and among the 38 with radical radiotherapy the rates in T1-3 were 46, 36 and 13%. Transurethral resection was successful in most Ta cases. Most T1 tumours were, like T2-4, of higher grade than Ta. Prognosis was worse in T1 than in Ta. After progression to muscle-invasive disease, even during close follow-up the outlook was poor, as poor as for patients with primary muscle-invasive disease.  相似文献   
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Traumatic infarction of the spinal cord in children   总被引:2,自引:0,他引:2  
Infarction of the spinal cord in childhood is rarely due to trauma. During a 15-year period (1971 to 1985), eight children were admitted to The Hospital for Sick Children, Toronto, with a diagnosis of traumatic infarction of the spinal cord. All of these patients had delayed onset of neurological signs varying between 2 hours and 4 days after their initial trauma. No bone abnormalities were seen on plain spine x-ray films. Myelography was carried out in seven of these children and found to be normal in all seven. Six patients who were paraplegic at the time of admission remained permanently paraplegic, but two with incomplete cord signs did show some improvement.  相似文献   
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The effects of nonprotein energy source (ie, glucose only vs glucose and lipid) on nitrogen retention and total-body protein turnover were studied in 20 parenterally fed newborn infants. All infants received approximately 3 g amino acids and 80-90 kcal.kg body wt.d. Total-body protein synthesis was estimated by using three constant-infusion, end-product methods: enrichment of urinary urea and ammonia in response to a [15N]glycine label and exhaled carbon dioxide enrichment in response to a [1-13C]leucine label. No differences were seen in nitrogen retention between the two energy sources. The estimate of total-body protein turnover obtained from the 13C label was similar to that obtained with the [15N]urea label. No differences in turnover rates were observed between the two diet groups. Use of the glucose-plus-lipid fuel system enhanced energy storage and the reutilization of amino acid for protein synthesis.  相似文献   
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