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To determine whether therapy with exogenous insulin or sulfonylureas results in a postprandial pattern of carbohydrate metabolism in patients with non-insulin-dependent diabetes mellitus (NIDDM) that resembles that in nondiabetic individuals, we employed a dual-isotope technique combined with forearm catheterization to examine meal disposition in NIDDM patients, before and after 3 mo of therapy with tolazamide and after 3 mo of therapy with exogenous insulin, with a randomized crossover design. Results were compared with those observed in nondiabetic subjects. Although both forms of therapy improved chronic glycemic control (glycosylated hemoglobin concentration went from 9.6 +/- 0.7 to 7.6 +/- 0.5 and 7.1 +/- 0.2%, respectively, P less than .01), exogenous insulin resulted in a lower postprandial glycemic response than tolazamide (P less than .001). Both agents comparably increased (P less than .01) fasting and integrated postprandial insulin concentrations. However, the initial rate of postprandial increase was greater with exogenous insulin (P less than .05). Tolazamide (P less than .05) but not exogenous insulin increased postprandial C-peptide concentrations. However, tolazamide did not improve the deficient early insulin release. Both agents (P less than .05) lowered postabsorptive hepatic glucose release (from 2.8 +/- 0.3 to 2.3 +/- 0.2 mg . kg-1 . min-1), but not to normal rates (1.8 +/- 0.1 mg . kg-1 . min-1).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Fady K. Balaa T. Clark Gamblin Allan Tsung J. Wallis Marsh David A. Geller 《Journal of gastrointestinal surgery》2008,12(2):338-343
Background Application of linear stapling devices for extrahepatic vascular control in liver surgery has been well-established. However,
the technique for use of stapling devices in hepatic parenchymal transection is not well defined.
Purpose To describe the safety and efficacy of our technique for use of vascular stapling devices in hepatic parenchymal transection
during open right hepatic lobectomy is the purpose of this study.
Methodology We reviewed our experience with 101 consecutive open right hepatic lobectomies performed by a single surgeon between January
2003 and July 2006, in which vascular staplers were utilized for the parenchymal transection phase.
Results Of the 101 patients who underwent resection, 53 (52%) were female. The mean age was 58 years. Malignant disease was the indication
for resection in the majority of patients (88%). Of those with cancer, 78% (69 of 89) had metastatic colorectal cancer, 6%
(5 of 89) had metastatic neuroendocrine tumor, 4% (4 of 89) had hepatocellular carcinoma, 4% (4 of 89) had cholangiocarcinoma,
and the remaining 8% were other metastatic cancers. Twelve patients (12%) underwent resection for hepatic adenoma or symptomatic
benign disease (FNH or hemangioma). Forty-eight patients (48%) underwent a major ancillary procedure at the time of hepatic
resection. Thirty-nine patients (39%) had a nonanatomic wedge resection of a left lobe lesion, 27 patients (27%) had one or
more lesions treated with radiofrequency ablation (RFA), and 6 patients (6%) were treated with a synchronous bowel resection.
The median total operative time was 336 min (range 155–620 min). A Pringle maneuver for temporary vascular inflow occlusion
was utilized in all cases, with a median time of 9 min (range 4–17 min). Ten patients (10%) required blood transfusion during
surgery or in the postoperative period. The maximum transfusion was 2 U of packed red blood cells (PRBC) in seven patients
and 1 U of PRBC in three patients. The mean nadir postoperative hematocrit was 28.2. All patients with malignant disease had
tumor-free margins at the completion of the procedure. The average hospital length of stay was 6.0 days. One patient (1%)
developed a clinically significant bile leak requiring a postoperative endoscopic retrograde cholangiography (ERCP). No patient
required reoperation. The 30 and 60-day postoperative survival was 100%.
Conclusion These findings indicate that application of vascular stapling devices for parenchymal transection in major hepatic resection
is a safe technique, with low transfusion requirements and minimal postoperative bile leak. The technique allows for rapid
transection of the entire right hepatic lobe in under 10 min. Short video clips of the technique will be demonstrated.
Presented at the 2007 American Hepato–Pancreato–Biliary Association, Las Vegas, Nevada, April 19–22, 2007 (oral presentation/video
presentation). 相似文献
5.
Cholinoceptor-mediated mechanical and electrical responses of rat oesophageal striated musculature. A comparison of two in vitro methods 总被引:1,自引:0,他引:1
1. Both muscarinic and nicotinic cholinoceptor agonists produce a contractile response of the rat oesophageal tunica muscularis externa (TME) in vitro. 2. The muscarinic receptor-mediated responses were confined to the distal 0.5 cm of the TME, which contains an admixture of smooth muscle. 3. Nicotinic receptor-mediated responses were obtained throughout the length of the TME striated musculature and consisted of a fast and slow component, representing TTX-sensitive contractions, associated with muscle action potentials, and electrically silent contractures, respectively. 4. Contractions were observed only in superfused preparations. 5. Contractures were resistant to changes in extracellular cation concentrations designed to eliminate generation of nerve and muscle action potentials or release of neurotransmitters. 相似文献
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Pattern of postprandial carbohydrate metabolism and effects of portal and peripheral insulin delivery 总被引:4,自引:0,他引:4
E J Kryshak P C Butler C Marsh A Miller D Barr K Polonsky J D Perkins R A Rizza 《Diabetes》1990,39(2):142-148
The importance of portal insulin delivery in the regulation of postprandial carbohydrate metabolism is uncertain. To address this question, three groups of dogs were studied: one group in which pancreatic venous drainage was transected and reanastomosed (portal insulin delivery), one in which the pancreatic drainage was transected and anastomosed to the inferior vena cava (peripheral insulin delivery), and one that received only a sham operation. Plasma insulin was greater (P less than 0.05) during peripheral insulin delivery than in either the portal or sham groups, respectively, before and after meal ingestion. On the other hand, C-peptide concentrations did not differ between groups, resulting in a higher (P less than 0.001) insulin to C-peptide ratio in the peripheral group. This indicated that the hyperinsulinemia in the peripheral group was due to decreased insulin clearance rather than increased insulin secretion. Isotopically determined splanchnic uptake of ingested glucose, postprandial suppression of hepatic glucose release, incorporation of CO2 into glucose (a qualitative measure of gluconeogenesis), and total-body glucose uptake were virtually identical in all groups. Similarly, plasma lipid, beta-hydroxybutyrate, and lactate concentrations did not differ between groups. Our data indicate that, despite differences in systemic insulin concentration, portal and peripheral insulin delivery comparably regulate hepatic and extrahepatic carbohydrate metabolism after meal ingestion. 相似文献
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Testicular microlithiasis: sonographic and clinical features. 总被引:7,自引:0,他引:7
D L Janzen J R Mathieson J I Marsh P L Cooperberg P del Rio R H Golding M D Rifkin 《AJR. American journal of roentgenology》1992,158(5):1057-1060
Eleven cases of bilateral diffuse microlithiasis of the testes were evaluated sonographically. The presence of testicular microlithiasis was coincidental to the presence of testicular neoplasms (n = 2), nontesticular malignant lesion in the abdomen or chest (n = 2), subfertility (n = 2), varicocele (n = 1), epididymitis (n = 1), testicular maldescent (n = 1), scrotal trauma (n = 1), and transient scrotal pain (n = 1). Clinical follow-up suggested that testicular microlithiasis is an asymptomatic nonprogressive condition. Sonographic examination of testicular microlithiasis shows diffuse hyperechoic nonshadowing foci measuring 1-2 mm in diameter throughout both testes. The diagnosis of testicular microlithiasis was pathologically proved in five cases. In six cases, the diagnosis was made on the basis of the sonographic appearance (n = 6), clinical information and follow-up (n = 6), and radiologic demonstration of testicular microcalcifications (n = 3). The sonographic appearance of testicular microlithiasis is specific, and we believe that biopsy or orchiectomy in these cases is unnecessary. 相似文献
10.
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information. 相似文献