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991.
Nucleolar organizer regions in meningioma   总被引:1,自引:0,他引:1  
Seventy-eight cases of meningioma and related tumors were examined independently using a simple and reproducible argyrophilic method for the demonstration of nucleolar organizer regions (AgNORs) and staining with bromodeoxyuridine monoclonal antibody. The mean number of AgNORs per cell and the bromodeoxyuridine labeling index were shown to be linearly related (r = 0.84, P less than 0.001). The mean AgNOR number was 2.99 for meningeal sarcoma, 2.29 for anaplastic meningioma, 2.08 for hemangiopericytic meningioma. 1.72 for recurrent meningioma without atypical histological findings, and 1.52 for nonrecurrent meningioma. We noted that the mean number of AgNORs reflected the cellular kinetics of a tumor and was related to histological grade and clinical behavior.  相似文献   
992.
The coexistence of otosclerosis and endolymphatic hydrops in the temporal bone have been described; however, the mechanism for the development of endolymphatic hydrops in otosclerosis remains unknown. Among 128 temporal bones with otosclerosis, involvement of the vestibular aqueduct by otosclerosis was observed in four temporal bones from two patients. In all four, the vestibular aqueduct was filled with active otosclerotic foci; the lumen of the endolymphatic duct and sac was narrowed as a result of fibrosis, and endolymphatic hydrops, more severe in the pars inferior than the pars superior, was observed. Collapse of the ductus reuniens and dilated saccule was seen in three temporal bones. Our study indicates that otosclerotic obstruction of the vestibular aqueduct may create a disturbance of the outflow and/or absorption of endolymph, leading to the development of endolymphatic hydrops and Meniere's disease, thus supporting the theory of longitudinal flow of endolymph.  相似文献   
993.
Intraluminal fluid movement rate was measured in four regions of the rat epididymis. The fastest flow occurred in the proximal caput epididymis (18.5 +/- 3.7 mm/hour) and the slowest in the distal cauda (2.5 +/- 0.5 mm/hour). Vasectomy significantly reduced caput fluid flow rates unless a sperm granuloma was present at the vasectomy site. Thirty days after vasovasostomy, caput fluid movement remained reduced in animals unless a granuloma was present. Failures of this or other aspects of epididymal biology to return to normal after vasovasostomy could play a role in the frequent infertility which persists after the operation.  相似文献   
994.
Ketogenic capacity of mitochondria from the remnant liver of 70% hepatectomized rats was studied in relation to mitochondrial phosphorylative activity. Ketogenic capacity increased to a maximum of 6.04 +/- 0.39 from 3.84 +/- 0.13 of control, with an enhancement of mitochondrial phosphorylative activity 6 hr after hepatectomy, and then decreased to normal levels within 24 hr. Adenylate energy charge, (ATP + 1/2ADP)/(ATP + ADP + AMP), of the remnant liver decreased to 0.825 +/- 0.006 as compared to 0.849 +/- 0.002 of control 6 hr after operation. At 12 hr, total ketone body concentrations of the arterial blood increased concomitant with a fall in ketone body ratio (acetoacetate/3-hydroxybutyrate) which reflects the decreased liver mitochondrial redox (NAD+/NADH) state. These findings suggest that an enhancement of mitochondrial fatty acid oxidation and ketogenesis occurs concomitant with an enhancement of mitochondrial phosphorylative activity in the remnant liver in response to a decreased energy charge after 70% hepatectomy.  相似文献   
995.
Two different regimens of cephalosporin antibiotic prophylaxis were compared with antiseptic lubricating jelly to try to prevent infection and complications in 196 men after prostatic surgery. Pre-operative urine was cultured and prostatic chips (170 cases) were also cultured to define the source of any infection. The use of antibiotics was associated with a reduced risk of postoperative bacteriuria. No serious complications occurred, although 1 patient in the antiseptic treated group developed rigors; 79 of 170 patients (46%) had positive prostatic chip cultures, of whom 74 had sterile pre-operative urine. There was no association between the result of chip culture and the presence of a pre-operative catheter. Culture positive patients had an increased risk of post-operative urine infection, although the same organism was found in the prostate and urine in only 36% of cases of post-operative bacteriuria and in 43 (54%) the organism cultured from the prostate was Staphylococcus albus. This study provides further evidence of the benefit of true prophylactic antibiotic therapy for transurethral prostatic surgery and the prostatic chip data suggest that some of the risk is due to pre-operative contamination of the prostate in the absence of per-operative urinary infection or catheterisation.  相似文献   
996.
12 giant intracranial aneurysms were studied by MRI. Intraluminal thrombosis was observed in 9 aneurysms. Thrombosis was found more frequently in larger aneurysms. Thrombi were formed posteriorly or inferiorly in the lumen of 4 among 5 IC-cavernous aneurysms. Location of the neck of the aneurysms and stagnation of blood flow influenced by gravity may be causative factors determining the location of thrombi. In 6 aneurysms intraluminal thrombi were inhomogeneous on MRI, suggesting that the thrombi had been formed at different times. New thrombi were formed between the aneurysmal wall and the old thrombus in 3 cases. Dissection of the aneurysmal wall by residual blood flow in the lumen or hemorrhage in the aneurysmal wall may be one of the growth mechanisms of giant intracranial aneurysms.  相似文献   
997.
The hepatic circulation of patients with hilar carcinoma and icterus was studied by isotope technique. A marked alternation in blood flow was observed, that is that the ratio of the circulation of the hepatic artery and the portal vein became balanced. By elimination of the icterus, the hepatic circulation normalized. This allowed the conclusion that the change in blood flow must have rather been due to the mechanical icterus and the increased pressure of the bile duct than to the tumorous infiltration and therefore the earliest possible elimination of the icterus is urgently indicated.  相似文献   
998.
The pathomorphological and clinical findings were investigated in 10 cases of drug-induced hypersensitivity nephritis. Hypersensitivity due to drugs was strongly suggested by the lymphocyte stimulation test in all patients. The offending drugs included penicillin, cephem derivatives, nonsteroidal anti-inflammatory drugs, and minocycline. All patients developed acute renal failure shortly after administration of regular doses of the drugs. Allergic symptoms plus a raised level of serum IgE or eosinophilia were seen in 7 patients. The remaining 3 patients receiving nonsteroidal anti-inflammatory drugs had no allergic symptoms, but developed severe proteinuria. Eight patients without severe glomerular damage recovered after withdrawal of the offending drugs and temporal dialysis and/or steroid therapy. Renal biopsies revealed tubulitis and tubular epithelial degeneration with interstitial edema as the common characteristic findings. Granulomatous lesions were occasionally observed. Multinucleated giant cells found in the granulomas were positive for LN-3 which is compatible with HLA-DR antigen. The glomeruli appeared normal, except in 2 cases in whom crescentic glomerulonephritis and thrombotic microangiopathy were seen. Our study suggests that the lymphocyte stimulation test and renal biopsy are the most useful means to confirm the diagnosis and provides further evidence for the participation of cell-mediated immunity in the pathogenesis of drug-induced hypersensitivity nephritis.  相似文献   
999.
The renal and hemodynamic effects of dopamine were measured during the immediate postoperative period in six infants following repair of congenital cardiac defects. Dopamine was infused at rates of 5, 10, and 15 micrograms/kg/min. Cardiac index (CI) increased significantly at a dopamine infusion rate of 15 micrograms/kg/min. The glomerular filtration rate (GFR) and urine output increased at dopamine infusion rates of 5 and 10 micrograms/kg/min and returned to baseline at 15 micrograms/kg/min. No significant changes occurred in right atrial pressure (RAP), left atrial pressure (LAP), systemic artery pressure, systemic vascular resistance (SVR), or pulmonary vascular resistance (PVR). Heart rate (HR) increased slightly at a dopamine infusion rate of 15 micrograms/kg/min. Pulmonary artery pressure (PAP) increased significantly in only one patient. These data demonstrate that infants require high doses of dopamine to produce the hemodynamic effects seen in adults and that these higher doses may be used without adverse renal effects.  相似文献   
1000.
Estramustine phosphate disodium (Estracyt) was used in the treatment of 38 patients with prostatic carcinoma for at least 1 year. Of these patients 37 patients were treated with Estracyt as primary treatment and 1 patient had been treated with another antiandrogenic therapy before the Estracyt treatment. Estracyt was given orally in a dose of 560 mg/day in divided oral doses. The clinical evaluation was done for the change of PAP, the relapse rate, the survival rate and the side effect. Among 22 cases which had shown abnormally high PAP values before the treatment started, the values decreased or normalized in 21 cases (95.5%) in the first year of administration of Estracyt. In 6 cases, however, the values increased again in the second year or later. Relapse was observed in 10 (26.3%) out of 38 cases. Relapse rate was 2.6%, 51.7%, and 51.7%, at the first, third, and fifth year, respectively. Survival rate was 97.4% at the first year, 88.5% at the third year, and 68.8% at the fifth year for the follow-up study. Side effects were observed in 14 (36.8%) out of 38 cases. The main side effect was gynecomastia. Gastro-intestinal disturbance and edema were also observed. However, there were only 2 cases (5.2%) in which administration of Estracyt had to be discontinued.  相似文献   
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