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31.
The effect of tetrachloroethylene on Phase I and II drug-metabolizing enzymes in rat liver was examined. Rats were treated orally with tetrachloroethylene daily for five days, at doses of 125, 250, 500, 1,000 and 2,000 mg/kg. The higher doses (>500 mg/kg) of tetrachloroethylene induced the hepatic microsomal 7-pentoxyresorufin O-depentylase and 7-benzyloxyresorufin O-debenzylase activities associated with the CYP2B subfamily. 7-ethoxyresorufin O-deethylase activity was also induced about 2-fold compared with that of control rats at 500, 1,000, and 2,000 mg/kg dose levels of tetrachloroethylene. However, 7-ethoxycoumarin O-deethylase and 7-methoxyresorufin O-demethylase activities were increased significantly at only the 1,000 mg/kg dose level of tetrachloroethylene (1.4- and 1.5-fold). Although other cytochrome P450-mediated monooxygenase activities such as nitrosodimethylamine N-demethylase, aminopyrine N-demethylase and erythromycin N-demethylase were also induced by tetrachloroethylene, the relative induction to control activity was lower than those of 7-pentoxyresorufin O-depentylase and 7-benzyloxyresorufin O-debenzylase. Western immunoblotting showed that the levels of CYP2B1 and CYP2B2 proteins in liver microsomes were increased at doses of 1,000 and 2,000 mg/kg of tetrachloroethylene. In addition to cytochrome P450-mediated monooxygenases, there was significant induction of the Phase II drug-metabolizing enzymes, DT-diaphorase, glutathione S-transferase activities towards 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene, and UDP-glucuronyltransferase activities towards 4-nitrophenol and 7-hydroxycoumarin. The results indicate that tetrachloroethylene induces both Phase I (CYP2B-mediated monooxygenase) and Phase II drug-metabolizing enzymes (DT-diaphorase, glutathione S-transferase and UDP-glucuronyltransferase) in the rat liver.  相似文献   
32.
Balloon plasty with a Meditec balloon dilatation catheter was performed in thirteen patients who had choledochal cysts with intrahepatic biliary strictures. The age of the patients ranged from one to 28 years. Eleven were female, and two were male. The site of the biliary stricture was both the right and left hepatic duct in eight patients, the left hepatic duct in four, and the right hepatic duct in one. Balloon plasty was performed postoperatively through the fistula of the percutaneous transhepatic drainage tube in seven patients and during the operation in six. Dilatation was adequate in ten patients but insufficient in three. The preoperative imaging character of the biliary strictures in the successful cases was membranous stenosis of less than 2mm in length. In contrast, the strictures of the patients with insufficient dilatation were long stenoses of more than 5mm in length.  相似文献   
33.
Infective endocarditis of the mitral area accompanied by anorexia nervosa is extremely rare. A 34-year-old Japanese woman presented with high fever and a heart murmur that had developed over the previous 2-month period. Echocardiography revealed mitral regurgitation and vegetation attached to the anterior mitral leaflet, which had markedly prolapsed to the left atrium. We removed the vegetation with a small part of the anterior mitral leaflet and successfully repaired the mitral valve. The patient showed good recovery, and the mitral regurgitation and left ventricular chamber size had satisfactorily decreased at 2 months after the operation.  相似文献   
34.
Liver transplantation, which serves as treatment of familial amyloidotic polyneuropathy (FAP), and domino liver transplantation, which utilizes resected livers from patients with FAP for treatment of liver diseases, may induce changes in transthyretin (TTR), a pathogenic FAP-related protein. To evaluate this possibility, we performed a 70% hepatectomy or administered tacrolimus to Dark Agouti (DA) rats for 7 days and then measured changes in liver TTR mRNA levels and changes in serum TTR concentrations. After hepatectomy, TTR mRNA levels decreased by 77%; at day 3, they returned to preoperative levels. Except for slightly elevated serum TTR concentrations 12 h after operation, serum TTR levels remained unchanged. Thus, partial hepatectomy did not influence serum TTR concentrations. After tacrolimus administration, TTR mRNA declined by 56% 12 h after the experiment started; however, after day 3, a rebound phenomenon occurred until day 7. Tacrolimus may facilitate serum TTR degradation, although production of TTR in the liver also increased. This finding -- that TTR, the source of FAP-inducing amyloid, did not increase after transplantation -- may help post-transplantation treatment of patients who have FAP and other liver diseases.  相似文献   
35.
This study examined the acid base disturbances in 18 adults with acute renal failure (ARF) from one of new aspects, which is lactate metabolism and pathophysiology. 10 patients (55%) of them were accompanied by lactic acidosis and 9 patients (90%) of those with lactic acidosis also had severe hepatic failure. Mortality of patients with lactic acidosis was 80%, and much higher than that of ARF (66.7%). Lactate, pyruvate, lactate-to-pyruvate ratio (L/P) were 76.7 +/- 15.66 mg/dl, 3.30 +/- 0.74 mg/dl and 19.9 +/- 1.41, respectively. All of them significantly raised, compared to values of healthy adults, patients with liver cirrhosis, chronic renal failure and diabetes mellitus. Arterial pH and HCO3- levels were 7.20 +/- 0.04 and 10.6 +/- 1.20 mEq/l. Anion gap (AG) was 30.0 +/- 3.66 mEq/l. Significant correlations of lactate with pH, HCO3-, AG and L/P were demonstrated, while correlations of lactate with BUN, CR and prothrombin time were not significantly observed. Lactic acidosis results from two mechanisms. One is lactate overproduction (e.g tissue hypoxia) and the other is lactate underutilization (e.g severe liver and/or renal failure). Whenever lactic acidosis occurred, both mechanisms were present simultaneously and continuously. Especially, the latter mechanism had a very important role on it, and seemed to decide the prognosis of the patients with lactic acidosis. Therapy of lactic acidosis was very difficult. First of all, we tried to improve the circulatory failure and severe acidemia (pH less than 7.20) not to fall into vicious cycle. Then, CAVH, if combined with alkali infusion, seemed to be the most useful technique in managing lactic acidosis with ARF.  相似文献   
36.
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent hydrocephalus development. Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with (group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal shunt (VPS) placement. Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth required VPS placement (p=0.0001). Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine the necessity for VPS placement.  相似文献   
37.
Abnormal DNA content has been considered as an additional criterion for determining the biological behavior of a tumor. Flowcytometric DNA analysis was done on 121 patients with thyroid carcinoma encountered during the period between 1975 and 1987. Tumor tissues were sampled from paraffin-embedded blocks and the histology of thyroid carcinoma found to consist of 91 papillary, 23 follicular, 2 medullary, 1 squamous cell and 4 anaplastic carcinomas. The incidence of aneuploidy in thyroid carcinoma was 7.4 per cent (9 patients) while that of diploidy was 92.6 per cent (112 patients). The aneuploid specimens consisted of 6 papillary, 1 follicular, 1 medullary and 1 anaplastic carcinomas and, of 4 anaplastic carcinoma patients with subsequent death within 6 months, only 1 was aneuploid. As an indicator of proliferative potential, S-phase fraction (SPF) was also determined by flow cytometry, but this could not be used as an independent prognostic factor. The aneuploid patients showed a significantly decreased survival rate (p less than 0.01). Thus, although DNA measurement proved useful for predicting the survival of aneuploid patients, there is some discrepancy between DNA content and the biological behavior of the tumor.  相似文献   
38.
39.
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction.  相似文献   
40.
We studied mechanism to induce scoliosis in Duchenne muscular dystrophy (DMD) by use of X-ray computed tomography (CT) of paraspinal muscles. CT examination of paraspinal muscles was performed on 15 DMD patients at the following six levels; 1. Th3 vertebrae (upper thoracic spine level) 2. Th6 vertebrate (middle thoracic spine level) 3. Th10 vertebrae (lower thoracic spine level) 4. L1 vertebrae (upper lumbar spine level) 5. L3 vertebrae (middle lumbar spine level) 6. L5 vertebrae (lower lumbar spine level). We evaluated the degeneration of paraspinal muscle by a decrease in radio-density of the muscle which indicates infiltration of fatty tissue. The degeneration of the lateral portion of paraspinal muscle was more marked than that of the medial portion. The muscle was most severely affected at the middle lumbar spine level, showing a tendency to increase degeneration at the lower level of the spine. In cases showing laterality of the degeneration of paraspinal muscle, the less affected muscle on CT was located at the convex site of scoliosis. We speculate that the scoliosis occurs when DMD patients have asymmetrical paraspinal muscle degeneration, leading them to take compensatory posture.  相似文献   
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