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761.
762.
A total of 508 patients had an non-decompression surgery for esophago-gastric varices in our department, from September 1979 to December 1991. These patients consisted of 387 cases of transthoracic esophageal transection with para-esophagogastric devascularization, 40 cases of transabdominal esophageal transection, and 81 cases of Hassab procedure. The original diseases were cirrhosis in 432 patients, IPH in 35, extrahepatic-portal occlusion in 24, primary biliary cirrhosis in 6, Budd-Chiari syndrome in 4, and others in 7. Operative mortality rate was 5.3%. By thoracic approach, esophageal varices completely disappeared. Postoperative cumulative variceal recurrence and bleeding rates at 10 years were 12% and 7%, although recurrence occurred more often than not in cases with hepatocellular carcinoma (HCC). Cumulative survival rates at 5, 10 years were 69%, 46% in liver cirrhosis without HCC. Present study confirmed that our non-decompression surgery is effective in controlling esophagogastric varices in long term of periods.  相似文献   
763.
764.
The pharmacokinetics of chenodeoxycholic acid (CDCA) in hepatic dysfunction were evaluated by analyzing the plasma disappearance curves after simultaneous administration of [3H]- and [14C]-CDCA through the femoral and portal veins, respectively, in dogs chronically intoxicated with dimethylnitrosamine (DMN). The plasma concentration-time curve of intravenously administered [3H]-CDCA was best fitted to a three-exponential equation, while that of intraportally administered [14C]-CDCA was fitted to either a two- or a three-exponential equation. In the DMN-intoxicated dogs, significant decreases were observed in total body plasma clearance (CLp), hepatic extraction ratio (EH) and apparent intrinsic clearance (CLint) compared to those of the untreated (control) dogs. The hepatic blood flow (QH), calculated from CLp, CLint and blood-to-plasma concentration ratio (RB) according to the equation reported by Wilkinson and Shand [Clin. Pharmac. Ther. 18, 377 (1975)], was reduced to approximately 70% in the DMN-intoxicated dogs compared to the control dogs. The bindings of CDCA to plasma and liver cytosol fraction were determined by equilibrium dialysis; no significant difference was observed in the unbound fraction between the DMN-treated and control dogs. By comparing both pharmacokinetic parameters obtained from intravenous and intraportal administration, the usefulness of the oral bile acid tolerance test was examined. From these findings, it was suggested that the decrease in the CLp of the DMN-intoxicated dogs was due to both the decrease in QH and that in CLint, and that the decrease in CLint may be due not to an alteration of plasma or cytosol binding but to that of a carrier-mediated transport system. It is also suggested that the measurement of fasting plasma bile acid concentration or the oral bile acid tolerance test is more sensitive for the detection of hepatic dysfunction than the intravenous bile acid tolerance test.  相似文献   
765.
766.
The occipital transtentorial approach (OTT) is showed to be effective not only for pineal body tumors, but also for superomedial cerebellar tumors. We satisfactorily removed a superomedial cerebellar astrocytoma in a 3-year-old infant using OTT. The magnetic resonance images showed a tumor located in the left superomedial cerebellum, and the distance between the midline and the outer margin of the tumor was 2.5 cm. OTT was performed on the left side, and the tumor was removed completely. Herein, relying on own experiments and some reports, we discussed some helpful techniques and the indications for OTT for superomedial cerebellar tumors. In brief, an arch shift of the superior sagittal sinus to the contralateral side by tracting the dura, a long incision of tentorium, and aspiration of CSF were very useful measures for avoiding occipital lobe injury. We emphasized that a preoperative estimation of possibilities for these techniques is very important.  相似文献   
767.
768.
Despite the rarity of desmoplastic cerebral astrocytoma of infancy (DCAI), it has distinct clinical and pathological features. The present case is a typical DCAI except for its detection and operational age and intermingling with pleomorphic glial cells. In this case, although a cystic lesion of the right temporal lobe was noticed when the patient was 6 months old, it was not regarded as a tumor and wasn't removed until he was 9 years old. It is quite unusual that a DCAI was able to exist in the cerebrum for 9 years. However, no metastasis occurred and distinct macroscopic and microscopic features of the tumor were not different from typical DCAI except for an intermingling with pleomorphic glial cells. Furthermore, even in the pleomorphic areas, the absence of necrosis and an MIB-1 index of 2.9% indicated non-aggressive growth. These features of the present case may provide additional information as to the character of DCAI, which generally has a favorable prognosis.  相似文献   
769.
Carboxymethylated chitin, gellan gum, and curdlan gels were soaked in a simulated body fluid (SBF) having ion concentrations nearly equal to those of human blood plasma. Some of the gels had been soaked in a saturated Ca(OH)(2) solution, while others had not. The carboxymethylated chitin and gellan gum gels have carboxyl groups, while the curdlan gel has hydroxyl groups. None of the gels formed apatite on their surfaces in the SBF when they had not been subjected to the Ca(OH)(2) treatment, whereas the carboxymethylated chitin and gellan gum gels formed apatite on their surfaces when they had been subjected to the Ca(OH)(2) treatment. The curdlan gel did not form an apatite deposit even after the Ca(OH)(2) treatment. Apatite formation on the carboxymethylated chitin and gellan gum gels was attributed to the catalytic effect of their carboxyl groups for apatite nucleation, and acceleration of apatite nucleation from released Ca(2+) ions. This result provides a guiding principle for obtaining apatite-organic polymer fiber composites. This composite is expected to have an analogous structure to that of natural bone.  相似文献   
770.
We reviewed five cases of sclerosing perineurial tumor of the hand. Four patients were male and one was female with ages ranging from 11 years to 49 years (mean 26 years). The predominant reason for consultation at the outpatient clinic was a slowly growing painless mass. The sites of involvement were the thumb in two cases, and the ring finger, middle finger and palm in one case each. The lesions were hard and firm, well-circumscribed white masses with a fibrous consistency ranging from 1.2 cm to 4.0 cm (mean 2.5 cm) in maximum dimension. Microscopically, all the tumors were composed of thick collagen and variable numbers of small, epithelioid cells exhibiting corded, trabecular and whorled growth patterns. Electron microscopy showed long cytoplasmic processes with a discontinuous basal lamina and occasional pinocytotic vesicles in the tumor cells. Immunohistochemically, most of the tumor cells were positive for epithelial membrane antigen, vimentin, collagen type IV and CD10, but not for S-100 protein, CD34, desmin and cytokeratin. We also observed that the tumor cells were positive for the human erythrocyte glucose transporter (GLUT1) antigen, suggesting that GLUT1 may be a useful marker for the identification of sclerosing perineurioma.  相似文献   
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