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61.
We examined the in vivo mechanisms of amylin-induced resistance in concious rats (n = 18). During 180-min euglycemic insulin-clamp (21.5 pmol.kg-1.min-1) studies, amylin (50, 200, or 500 pmol.kg-1.min-1; plasma concentration from 3 x 10(-10) to 9 x 10(-9) M) infusion determined a 19-27% reduction in glucose uptake (117.8 +/- 7.0 vs. 145.8 +/- 11.0, 107.1 +/- 9.2 vs. 145.1 +/- 6.7, and 105.0 +/- 7.2 vs. 144.4 +/- 7.0 mumol.kg-1.min-1 at 50, 200, or 500 pmol.kg-1.min-1, respectively, P less than 0.01) versus insulin alone, whereas 10-pmol.kg-1.min-1 amylin infusion (plasma concn 5 x 10(-11) M) failed to affect insulin-mediated glucose disposal. After amylin infusion, the contribution of whole-body glycolysis to overall glucose disposal increased from 43-48 to 62-79%, whereas muscle glycogen synthesis decreased significantly at all peptide concentrations greater than 3 x 10(-10) M, completely accounting for the decrease in glucose uptake. Skeletal muscle glucose-6-phosphate concentration rose from 0.219 +/- 0.038 mumol/g (insulin alone) to 0.350 +/- 0.018, 0.440 +/- 0.020, and 0.505 +/- 0.035 mumol/g (insulin plus amylin at 50, 200, or 500 pmol.kg-1.min-1, P less than 0.01). Suppression of hepatic glucose production by insulin was unaffected by a 50-pmol.kg-1.min-1 amylin infusion (18.5 +/- 4.3 vs. 21.7 +/- 2.9 mumol.kg-1.min-1), whereas it was slightly but significantly impaired by amylin infusion at 200 pmol.kg-1.min-1 (17.8 +/- 3.9 vs. 24.7 +/- 4.5 mumol.kg-1.min-1, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
62.
B I Choi  J K Han  Y H Park  Y B Yoon  M C Han  C W Kim 《Radiology》1991,178(1):105-108
Extracorporeal shock wave lithotripsy (ESWL) was performed in 11 patients with oriental cholangiohepatitis and intrahepatic stones associated with segmented strictures of intrahepatic ducts. All patients had previously undergone biliary surgery and basket extraction via a T-tube tract at the time of lithotripsy. The indication for ESWL was failure of, or anticipated difficulty with, basket extraction of the stones via a T-tube tract. A piezoelectric lithotriptor was used in all procedures. The average total number of shock waves administered was 29,756 (range, 10,000-61,395). The average number of treatment sessions was 3.1 (range, 1-6); the number of shock waves used in a single session ranged from 10,000 to 15,000 with a frequency of five shots per second and 30%-50% power. In six patients, the stones were successfully fragmented and completely removed; in three of the others of the stones were fragmented and removed. The overall success rate, including complete (54%) and incomplete (27%) success, was 82%. Difficulty in targeting stones, and severe strictures and deformities of intrahepatic ducts, were the factors responsible for failure. No significant complications were observed.  相似文献   
63.
Over twelve alkaloids were delected in the roots ofPanax ginseng C.A. Meyer. Among them three alkaloids were isolated and were identified as N9-formylharman, ethyl β-carboline-1-carboxylate and perlolyrine on the basis of spectroscopic studies.  相似文献   
64.
Simple closure, the conventional operation for perforated acute duodenal ulcers, is associated with symptomatic relapse in a large proportion of patients. In order to assess the role of immediate definitive surgery, 78 fit patients with perforated acute ulcers were prospectively randomized to undergo either closure alone or proximal gastric vagotomy with closure (PGV). Patients taking potentially ulcerogenic drugs or who had severe stress were excluded from the study. Both groups were comparable with respect to age, sex, general medical health, duration of perforation, length of ulcer history, and presence of duodenal scarring. There was no hospital mortality. Minor complications occurred in 7.3% after closure and 10.8% after PGV. At 3 years follow-up, the cumulative recurrence rates were 36.6% and 10.6% after closure and PGV, respectively (p = 0.001). Eighty-five per cent of recurrences after closure were symptomatic, and half of them required reoperation. Duodenal scarring itself did not appear to influence the outcome after closure. PGV was not associated with dumping, diarrhea or other unwanted side effects. Although less than that in chronic ulcers, there is a substantial risk of symptomatic relapse after closure of perforated acute duodenal ulcers. With judicious patient selection, PGV effectively reduces this risk without incurring disabling side effects associated with other ulcer operations.  相似文献   
65.
Forty-seven patients aged more than 75 years with acute pancreatitis were studied. The most common cause of acute pancreatitis was biliary tract stones. The clinical presentation and severity of the disease as judged by the number of poor prognostic factors were not different from the group of patients aged less than 75 years. The mortality rate in the older group was thrice that of the younger group (21.3% versus 7.24%). The higher mortality rate was explained by a higher incidence of deaths related to complications of biliary stones and coincidental diseases. Significantly more aged patients with mild disease died, indicating the limitation of predictive ability of the scoring system in acute pancreatitis of the aged.  相似文献   
66.
Influence of age on the mortality from acute pancreatitis   总被引:6,自引:0,他引:6  
The influence of age on the mortality rate of 268 patients with acute pancreatitis was studied. The hospital mortality rate for patients aged below 50 years was 5.9 per cent. The figure increased to 21.3 per cent in patients aged over 75; the high mortality was accounted for by a higher incidence of deaths related to concomitant medical or surgical diseases in the same hospital admission rather than to complications resulting directly from the pathological process of acute pancreatitis. When only deaths due to complications of acute pancreatitis were analysed, the mortality rate was not significantly different between the young and elderly groups. Moreover, the complication rate and the proportion of patients having severe disease (judged by the number of prognostic signs) were not higher in the elderly. Thus acute pancreatitis was intrinsically not more serious were it not for the presence of concomitant diseases with advanced age.  相似文献   
67.
Sonographic findings in 16 cases of Krukenberg tumor from gastric carcinoma were analyzed. The patients' ages ranged from 25 to 52 years (mean 42 years). The tumor involved both ovaries in 14 patients with asymmetrical masses in 9 of 14 cases. Ascites was noted in 15 cases. Echogenicity of the tumor varied from solid to predominantly cystic: solid in 8, mixed in 6, and predominantly cystic in 2 cases. Solid masses tended to be smaller than mixed or cystic masses. The primary gastric carcinoma had been diagnosed before emergence of the tumors in only 7 cases. The findings suggest that in relatively young patients with ovarian mass, particularly bilateral tumors, careful evaluation for gastrointestinal tract involvement should be done.  相似文献   
68.
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas.  相似文献   
69.
Endoscopic technologies have been developed greatly. As for early gastric cancer, the indications for endoscopic mucosal resection for early colorectal cancer have been widened recently. Technological advances can support wider and deeper resections using endoscopy but the remaining problem for the endoscopic management of cancer is lymph node metastasis. I discuss here the indication for endoscopic mucosal resection for early colorectal cancer to bring into focus the risk factors for metastasis to lymph nodes.  相似文献   
70.
Solid and papillary epithelial neoplasms of the pancreas: CT findings   总被引:1,自引:0,他引:1  
Choi  BI; Kim  KW; Han  MC; Kim  YI; Kim  CW 《Radiology》1988,166(2):413-416
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.  相似文献   
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