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Anastomotic healing is impaired after intestinal surgery because of ischemia and reperfusion injury (IRI), which can result in intestinal leaks leading to increased mortality. The objective of this study was to determine the effects of transplant IRI and immune mechanisms on intestinal graft anastomotic healing. Orthotopic intestinal transplantations (OIT) were performed in rats. The experimental design consisted of six groups A–F (n = 5/group): A, allogeneic OIT treated with tacrolimus (1mg/kg/day); B, syngeneic OIT treated with tacrolimus; C, syngeneic OIT; D, allogeneic OIT; E, proximal and distal anastomoses performed in nontransplanted animals; F, same as in group E but treated with tacrolimus. Anastomotic bursting pressure (ABP), hydroxyproline content (HPC), and mucosal inflammatory infiltrate (MII) were determined at the anastomotic sites (proximal and distal) and compared between groups. ABP was significantly (p < 0.001) reduced in OIT groups A, B, C, and D compared to control groups E and F at both the proximal and distal anastomotic sites. HPC was 1 g/mg of tissue in groups A, B, C, and D, and 5g/mg of tissue in groups E and F. This demonstrates a significant (p < 0.001) reduction in HPC after OIT. MII was significantly (p < 0.001) increased in OIT groups when compared to nontransplanted control groups. MII was also significantly (p < 0.05) increased in allogeneic OIT groups A and D compared to syngeneic OIT groups B and C. Generally, ABP and HPC were inversely proportional to MII in both nontransplanted control and OIT groups. Reduced anastomotic strength was demonstrated in both syngeneic and allogeneic OIT anastomotic sites irrespective of immunosuppressive therapy, and is probably related to IRI. 相似文献
103.
Hepatic insulin resistance precedes the development of diabetes in a model of intrauterine growth retardation 总被引:6,自引:0,他引:6
Intrauterine growth retardation (IUGR) has been linked to the development of type 2 diabetes in adulthood. We developed an IUGR model in rats whereby at age 3-6 months the animals develop a diabetes that is associated with insulin resistance. Hyperinsulinemic-euglycemic clamp studies were performed at age 8 weeks, before the onset of obesity and diabetes. Basal hepatic glucose production (HGP) was significantly higher in IUGR than in control rats (14.6 +/- 0.4 vs. 12.3 +/- 0.3 mg. kg(-1). min(-1); P < 0.05). Insulin suppression of HGP was blunted in IUGR versus control rats (10.4 +/- 0.6 vs. 6.5 +/- 1.0 mg. kg(-1). min(-1); P < 0.01); however, rates of glucose uptake and glycogenolysis were similar between the two groups. Insulin-stimulated insulin receptor substrate 2 and Akt-2 phosphorylation were significantly blunted in IUGR rats. PEPCK and glucose-6-phosphatase mRNA levels were increased at least threefold in liver of IUGR compared with control rats. These studies suggest that an aberrant intrauterine milieu permanently impairs insulin signaling in the liver so that gluconeogenesis is augmented in the IUGR rat. These processes occur early in life, before the onset of hyperglycemia, and indicate that uteroplacental insufficiency causes a primary defect in gene expression and hepatic metabolism that leads to the eventual development of overt hyperglycemia. 相似文献
104.
This paper utilizes the diffusion of innovation framework to discuss factors affecting adoption of telemedicine. Empirical and anecdotal findings are organized across five attributes affecting innovation adoption rates for the following four adopter groups: physicians, patients, hospital administrators, and payers. A discussion of the implications is included. 相似文献
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Nielsen HE Andersen EA Carlsen N Nir M Taaning E 《Acta paediatrica (Oslo, Norway : 1992)》2003,92(10):1208-1210
This study estimated the prevalence of serum antibodies against thrombocyte glycoproteins, at disease onset (54 patients) and later on during the course of the disease (71 patients), in sera from children with idiopathic thrombocytopenic purpura (ITP). Only a minority had serum antibodies at disease onset, with a significantly higher frequency in those who developed the acute form of the disease than in those who developed the chronic form. Serum antibodies may persist after spontaneous cure of acute disease. There was no switch from immunoglobulin M (IgM) to IgG antibodies over time. CONCLUSION: The pathogenesis of the acute and chronic forms of ITP may be different. 相似文献
108.
Gamzu R Achiron R Hegesh J Weiner E Tepper R Nir A Rabinowitz R Auslander R Yagel S Zalel Y Zimmer E 《Prenatal diagnosis》2002,22(11):1044-1047
OBJECTIVE: To evaluate the prenatal parameters that increase the risk of tuberous sclerosis in prenatal management of fetal cardiac tumors suspected as rhabdomyoma. METHODS: The study was a retrospective survey of 18 documented cases in which cardiac rhabdomyoma was suspected during pregnancy. The following parameters were evaluated as possible risk factors associated with tuberous sclerosis: tumor size, isolated or multiple, and family history of tuberous sclerosis. RESULTS: Eighteen documented cases in which cardiac rhabdomyoma was found during pregnancy were evaluated. Of these cases, seven (39%) had proven tuberous sclerosis and 11 were found to be non-associated tuberous sclerosis tumors. When combining the present data with previous series, cases with diagnosis of tuberous sclerosis had equal mean tumor size to those with normal outcome. Family history of tuberous sclerosis in the presence of cardiac rhabdomyoma almost invariably ended with tuberous sclerosis (86%). All other cases with diagnosis of tuberous sclerosis and no family history had all multiple cardiac tumors. CONCLUSION: The present data suggest that 39% of in utero suspected cardiac rhabdomyoma would have tuberous sclerosis. Family history and multifocality remain the strongest predictors of tuberous sclerosis, whereas size of the cardiac tumor can not reliably be used to predict tuberous sclerosis in prenatal counseling. 相似文献
109.
Nussinovitch M Sokolover N Volovitz B Amir J 《Archives of pediatrics & adolescent medicine》2002,156(10):1052-1054
BACKGROUND: Neurologic impairment is not considered a clinical manifestation of diskitis in children and has seldom been associated with it in the medical literature. OBJECTIVE: To describe neurologic findings and their implications in children with diskitis. STUDY DESIGN: Retrospective medical records review of children discharged with a diagnosis of diskitis between January 1992 and December 2000. The study included children in whom the diagnosis was based on the presence of clinical findings, laboratory evidence of an inflammatory process, and findings on imaging studies compatible with diskitis. RESULTS: Neurologic findings of decreased muscle strength or hyporeflexia in the lower extremities were found in 7 (41%) of 17 children who met the diagnostic criteria for diskitis. Five of the 7 underwent magnetic resonance imaging, 2 of whom demonstrated intraspinal inflammatory involvement. CONCLUSIONS: Neurologic impairment does not exclude the diagnosis of diskitis and may be a common manifestation of the disease in children. Nevertheless, when neurologic findings are present, advanced imaging studies are needed to exclude intraspinal involvement. 相似文献
110.