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91.
92.
Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates.  相似文献   
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Diagnosis of pancreatic carcinoma: role of FDG PET   总被引:1,自引:0,他引:1  
OBJECTIVE: The purpose of this study was to investigate the role of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in differentiating benign from malignant disease in patients with possible pancreatic malignancy. SUBJECTS AND METHODS: All patients with a possible diagnosis of pancreatic carcinoma based on CT or ERCP findings were eligible for inclusion in this prospective study. PET imaging of the abdomen was performed in 37 patients and was interpreted as positive if FDG activity in the pancreas exceeded background activity and as negative if activity was less than or equal to background activity. Semiquantitative analysis was performed by calculating a standardized uptake ratio. Studies were reviewed independently by two radiologists, and results were correlated with biopsy results and with CT and ERCP findings. Sensitivity and specificity of FDG PET for revealing pancreatic malignancy was determined. RESULTS: FDG activity in the pancreas was increased in 24 patients, and adenocarcinoma was diagnosed in 22 of these patients (92%). Two patients (8%) with increased activity had benign disease, including one patient with chronic pancreatitis who showed no evidence of tumor at laparotomy and one patient with a mucinous cystic tumor who showed no malignant features at laparotomy. FDG uptake was low or normal in 13 patients, 10 of whom (77%) had benign disease. FDG uptake was also low in three patients with adenocarcinoma, whose tumor size ranged from 2 to 4 cm in diameter. The mean standardized uptake ratio value for malignant disease was 5.1 (range, 1.0-10.1) and for benign disease was 1.9 (range, 0.0-5.8) (p < .001). The sensitivity of FDG PET for revealing malignant disease in the pancreas was 88% and the specificity was 83%. CONCLUSION: FDG PET is a sensitive and specific noninvasive technique for the diagnosis of pancreatic malignancy.  相似文献   
95.
The authors describe the use of the fiber bronchoscopic method in the respiratory distress syndrome of adults (RDSA). The method permits visual assessment of bronchial status and allows obtaining cell elements and mediators which are regarded not merely as a result of bronchoalveolar involvement, but as markers of the degree of this involvement. Special attention is paid to cellular and chemical components of bronchial secretion and to detection of correlation with the identical values of arterial and venous blood. The authors classify the available data on bronchological methods of examination, define their role in the diagnosis and treatment of RDSA, and analyze correlation between these data and clinical stages in the course of the syndrome.  相似文献   
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An immediate result of surgical treatment of gastric stump cancer in 68 patients is presented. The resectability rate was 23.5%. Lethality after radical operations was 18.7%, after symptomatic operations and exploratory laparotomy-9.6%. Gastric resection was performed, using the method developed in the clinic with wrapping the anastomosis, or gastric stump by a loop of the afferent intestine. In development of gastric stump cancer, local spreading of a tumor is not a reason to discard performance of radical operation.  相似文献   
99.
Experiments on CBA mice with alcohol withdrawal syndrome showed a reduction of abstinence after injection of serotonin antibodies in dose 5 and 10 mg intraperitoneally. One more result was a decrease of horizontal locomotory activity after injection of 5 mg of serotonin antibodies to mice with 24 hour withdrawal syndrome.  相似文献   
100.
Long term cell lines can be readily established at high frequency with PBLs from normal channel catfish. Depending upon the mode of stimulation, morphologically and functionally distinct catfish lymphoid cell lines resembling B cells, T cells and monocytes have been developed. These fish cell lines appear unique from their putative mammalian counterparts in that they are immortalized without the need for exogenous factors or overt attempts at transformation.  相似文献   
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