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991.
992.
Endobronchial leiomyoma is exteemely rare. Most endobronchial leiomyomas reported in the literature have been resected by either lobectomy or pneumonectomy. We herein report a case treated by sleeve bronchoplasty without pulmonary resection. A 42-year-old woman was admitted to our hospital complaining of hemoptysis. Bronchoscopy revealed a lobulated tumor arising from the medial wall of the right main stem bronchus. A sleeve resection of the right main bronchus including the tumor and end-to-end anastomosis was performed. The histological diagnosis of the resected specimen was leiomyoma with no evidence of malignancy. The importance of early diagnosis and appropriate surgical treatment to preserve pulmonary function are emphasized. Similar cases of an endobronchial type of pulmonary leiomyoma reported in the literature are also reviewed.  相似文献   
993.
Abstract: Using the molecular orbital methods, we examined molecular structure, electron density distribution, electrostatic potential field and receptor structure of gamma-aminobutyric acid (GABA), and its analogues. The following findings were obtained: a comparison of the biological activity and the morphology electrostatic potentials of GABA analogues disclosed that the active site is the amino group, and the biological activity correlates closely with the electrostatic potential structure around the amino group. The active sites were compared between the receptor-binding molecules and the GABA uptake inhibitory molecules, and the results suggested that the receptor structure differed between the two groups of molecules and that the GABA A receptors had two subtypes. On these results, the epileptogenicity of new quinolones was studied using this method. These results suggested that the new quinolones blockaded the GABA receptor-binding system and that the important active site of the new quinolones for GABA receptor-binding was the the piperazyl amino group. These results suggested that the concentration of zwitterion type of the new quinolones was very important clinically.  相似文献   
994.
Pulmonary artery pressure (PAP), cardiac output (CO), and urinary nitrate, a stable endproduct of nitric oxide (NO), were measured pre- and postoperatively in eight patients who underwent esophagectomy for squamous cell carcinoma of the thoracic esophagus. A significant elevation of PAP and CO on the day of operation (POD 0) was accompanied by a low concentration of urinary nitrate. A reduction in PAP and CO, and an increase in nitrate to the preoperative levels, were found on PODs 2 and 3, respectively, but urinary nitrate decreased again after POD 3. Consequently, the changes in PAP and CO were closely correlated with the nitrate concentration. These results suggest that operative stress inhibited NO synthesis with a transitory induction of endogenous NO synthesis postoperatively.  相似文献   
995.
We report two cases of carcinoma of the pancreas with anomalous junction of the pancreaticobiliary tracts. A 71-year-old Japanese woman had obstructive jaundice. Ultrasonography showed a hypoechoic mass in the pancreatic head and computed tomography demonstrated a low-density nodule in the pancreatic head. Endoscopic retrograde cholangiopancreatography displayed a double duct sign and an anomalous junction of the pancreaticobiliary tracts. The patient underwent a pancreatoduodenectomy. The histopathologic diagnosis of the resected specimen was adenocarcinoma of the pancreatic head. A 56-year-old Japanese man also developed obstructive jaundice. Ultrasonography and computed tomography showed a huge mass almost replacing the whole pancreas and involving the superior mesenteric artery, splenic artery, splenic vein, and portal vein. Multiple hepatic metastases and peritoneal dissemination were present. Endoscopic retrograde cholangiopancreatography demonstrated an anomalous junction of the pancreaticobiliary tracts. The patient died of hemorrhage from esophageal varices. We discuss the relationship between the anomalous junction of the pancreaticobiliary tracts and pancreatic carcinoma. Received for publication on May 30, 1997; accepted on Dec. 3, 1997  相似文献   
996.
SUMMARY: A 73-year-old man who had been undergoing chronic haemodialysis (CHD) for 3 years developed haemophagocytic syndrome (HPS) that might have been triggered by Epstein-Barr virus (EBV) infection. the patient finally died of miliary tuberculosis (TB) reactivation that promoted the progression of HPS. Immunological abnormalities in patients undergoing CHD may be notable. the early diagnosis of TB reactivation may be important for reducing the mortality in cases of HPS, as a high incidence of TB is encountered in patients undergoing CHD. In contrast, the simultaneous occurrence of an EBER-positive hybridization signal with T cell-specific immunolabelling of CD45RO cells was well detected in the spleen and lymph nodes, and interferon gamma was elevated in the serum. These findings coincide with the reported preferential expansion of T cells rather than B cells in EBV infection, and support the hypothesis that systemic hypercytokinaemia caused by the proliferation of EBV-infected T cells may play a crucial role in the development of HPS.  相似文献   
997.
Beta-hexosaminidases are important enzymes for lipid and saccharide metabolism in the brain. In mice deficient in these enzymes, indigestible metabolic intermediates deposit in neurons. Inclusions such as membranous cytoplasmic bodies (MCB) and zebra bodies were seen in neurons of Tay-Sachs (TS) model mice, Sandhoff's disease (SD) model mice, and double knockout (DKO) mice. However, the cerebral perivascular macrophages discovered by Mato are active in the uptake of waste products and regarded as scavenger cells under steady-state conditions. We observed that indigestible components derived from neurons were taken up by the perivascular macrophages of TS mice by pinocytosis, but those of SD and DKO mice contained only pale inclusions and had marked vacuolations, and pinocytosis was rarely observed. Histochemically, the inclusions in the perivascular macrophages of TS mice were positive for the PAS stain, but those of SD and DKO mice were negative. In addition, the perivascular cells of TS mice expressed clear positive immunoreactivity against BM-8 and F4/80, but those of DKO mice had very weak BM-8 and F4/80 immunoreactivity. These differences between TS, SD, and DKO mice are based on their metabolism of oligosaccharides and glycosaminoglycans (GAG). Thus, hexosaminidase B is more important for keeping normal morphology and function of perivascular macrophages than hexosaminidase A. The foamy cells that appeared along the cerebral microvessels in lipidosis and saccharidosis were identified as perivascular macrophages (Mato's fluorescent granular perithelial cells: FGP cells).  相似文献   
998.
For the evidence-based management of stroke, the first guideline was produced at 1994 from the American Heart Association, and also at 2000 from the United Kingdom. However, there is no such guidelines created in Japan yet. Due to the differences in therapeutic agents, disease subtypes, and races between our and other countries, we must create our own guidelines, taking into consideration of the evidences and situations from/in Japan. In this presentation, we addressed the following issues; 1) Historical overview regarding the evidence-based guidelines for the management of stroke. 2) Details about the Japan Joint Committee on Guidelines for the Management of Stroke (Chairman: Yukito Shinohara, Secretary-General: Masao Nagayama) which was established in October 2000 with the initiative of stroke-related societies in Japan. 3) Analysis of the recommendations and literatures describe-cited in the first draft of the Guidelines and the Evidence tables. 4) Problems and future directions in the therapeutic research of stroke management.  相似文献   
999.
1000.
The effect of green tea polyphenol fraction (GTP) on azoxymethane(AOM)-induced colon carcino-genesis was investigated in male Fischer rate. The rats were given AOM (7.4 mg/kg body weight) s.c. once a week for 10 weeks. A week after the treatment, they were divided into three groups: AOM-control (26 rats), AOM-GTP1 (26 rats) and AOM-GTP2 (25 rats). AOM-GTPl and AOM-GTP2 groups respectively received 0.01 and 0.1% GTP in drinking water from week 11 to 26. AOM-control group received tap water throughout this experiment. Autopsy on week 26 showed that tumor incidence and average numbers of tumors per rat in the AOM-GTPl and AOM-GTP2 groups were significantly lower than those of the AOM-control group: 38.1% and 47.6% versus 77.3%; 0.6 and 0.7 versus 1.5. Thus, it was concluded that GTP inhibited the development of AOM-indnced colon carcinogenesis. The inhibition by GTP did not show significant dose dependence.  相似文献   
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