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61.
Abstract An improved method of inducing diabetes in dogs was developed. This method included 90% pancreatectomy, 2 mg/kg streptozotocin (STZ) perfused into pancreaticoduodenal artery, and the fixation suture of the duodenum to the costo-abdominal wall. Vasopressin injection administered to the animals before surgery reduced bleeding. All dogs used in this procedure survived and became diabetic. One month after the procedure the pancreatic islets were reduced in volume and the number compared with pancreas tissue obtained during the surgery. Acinar tissue remained with a normal histology, and exocrine function maintained the physiological parameters, except for a soft faecal consistency. We conclude that this procedure is effective in inducing experimental diabetes in dogs.  相似文献   
62.
OBJECTIVES: a) To determine the rate of H. pylori reinfection after successful eradication in a 4-year follow-up study; and b) To evaluate the contribution of different factors in the infection relapse. PATIENTS AND METHODS: A total of 208 patients (age range 18-81 years; average 50 years; 87 women) who had been successfully treated for H. pylori infection were included. Annually, urea breath test was assessed to determine H. pylori status after eradication. Age, sex, rural/urban environment, smoking habit, treatment regimens against H. pylori and urea breath test values were evaluated. Results: reinfection occurred in 9,6% of patients observed, 6,7% (14/208) in the first year, 1,9% (4/208) in the second year, 1% (2/208) in the third and 0% in the forth. Risk factors for infection recurrence were younger age and higher values of urea breath test in the multivariante analysis. CONCLUSIONS: annual reinfection rate was 2,4 pacients-year. Younger patients and higher values of urea breath test were factors associated with a higher rate of reinfection relapse. Annually, urea breath test should be performed to detect reinfection in order to avoid ulcer complications.  相似文献   
63.
64.
A higher specific binding of GLP-1(7–36)amide is found in skeletal muscle plasma membranes from adult streptozotocin (STZ)-treated rats (insulin-dependent diabetes mellitus model) and from neonatal STZ-treated rats (non insulin-dependent diabetes mellitus model), as compared to that in normal controls; no apparent change in the affinity was observed, that indicating the presence in both diabetic models of an increased number of high affinity binding sites for the peptide. The maximal specific GLP-1(7–16)amide binding in the non insulin-dependent diabetes mellitus model was found to be significantly higher than that in the insulin-dependent diabetes mellitus model. As GLP-1(7–36)amide exerts a glycogenic effect in the rat skeletal muscle, the present data suggest that the action of the peptide in the muscle glucose metabolism may be increased in states of insulin deficiency accompanied or not by insulin resistance.  相似文献   
65.
66.
Concerns have been raised regarding the potential negative effects on human health of water disinfectants used in swimming pools. Among the disinfection options, the approaches using chlorine-based products have been typically preferred. Chlorine readily reacts with natural organic matter that are introduced in the water mainly through the bathers, leading to the formation of potentially harmful chlorination by-products (CBPs). The formation of CBPs is of particular concern since some have been epidemiologically associated with the development of various clinical manifestations. The higher the concentration of volatile CBPs in the water, the higher their concentration in the air above the pool, and different routes of exposure to chemicals in swimming pools (water ingestion, skin absorption, and inhalation) contribute to the individual exposome. Some CBPs may affect the respiratory and skin health of those who stay indoor for long periods, such as swimming instructors, pool staff, and competitive swimmers. Whether those who use chlorinated pools as customers, particularly children, may also be affected has been a matter of debate. In this article, we discuss the current evidence regarding the health effects of both acute and chronic exposures in different populations (work-related exposures, intensive sports, and recreational attendance) and identify the main recommendations and unmet needs for research in this area.  相似文献   
67.

Objective

A retrospective cohort study was preformed aiming to verify the presence of transient dysfunction of gas exchange in the postoperative period of cardiac surgery and determine if this disorder is linked to cardiorespiratory events.

Methods

We included 942 consecutive patients undergoing cardiac surgery and cardiac procedures who were referred to the Intensive Care Unit between June 2007 and November 2011.

Results

Fifteen patients had acute respiratory distress syndrome (2%), 199 (27.75%) had mild transient dysfunction of gas exchange, 402 (56.1%) had moderate transient dysfunction of gas exchange, and 39 (5.4%) had severe transient dysfunction of gas exchange. Hypertension and cardiogenic shock were associated with the emergence of moderate transient dysfunction of gas exchange postoperatively (P=0.02 and P=0.019, respectively) and were risk factors for this dysfunction (P=0.0023 and P=0.0017, respectively). Diabetes mellitus was also a risk factor for transient dysfunction of gas exchange (P=0.03). Pneumonia was present in 8.9% of cases and correlated with the presence of moderate transient dysfunction of gas exchange (P=0.001). Severe transient dysfunction of gas exchange was associated with patients who had renal replacement therapy (P=0.0005), hemotherapy (P=0.0001), enteral nutrition (P=0.0012), or cardiac arrhythmia (P=0.0451).

Conclusion

Preoperative hypertension and cardiogenic shock were associated with the occurrence of postoperative transient dysfunction of gas exchange. The preoperative risk factors included hypertension, cardiogenic shock, and diabetes. Postoperatively, pneumonia, ventilator-associated pneumonia, renal replacement therapy, hemotherapy, and cardiac arrhythmia were associated with the appearance of some degree of transient dysfunction of gas exchange, which was a risk factor for reintubation, pneumonia, ventilator-associated pneumonia, and renal replacement therapy in the postoperative period of cardiac surgery and cardiac procedures.  相似文献   
68.
69.
In vivo D-galactose absorption by the whole intestine between duodenum and rectum was studied in rats 1 month after sham operation, 50% proximal resection, intestinal bypass, or 50% distal resection. The total serosal areas were evaluated by means of an integrative method, obtaining reduced surfaces in resected or bypassed animals as compared with controls. The rate of D-galactose absorption, measured within 10 min, increased after proximal resection and bypass and diminished after distal resection, although the level was similar to that of controls at higher substrate concentrations. When expressed as serosal area, results in proximal and bypassed animals were higher than in controls, without differences (at lower galactose concentrations), and increased (at 25 mM), after distal resection. The total absorptive capacity related to wet and dry weight showed no differences in proximal and bypassed groups and a decrease after distal resection. The above results confirm a good level of recuperation when proximal intestinal surface is excluded. In case of ileal extirpation, a smaller compensatory response was found, which would be compensated for by a high substrate concentration in the intestinal lumen.  相似文献   
70.
Obesity and diets rich in uric acid–raising components appear to account for the increased prevalence of hyperuricemia in Westernized populations. Prevalence rates of hypertension, diabetes mellitus, CKD, and cardiovascular disease are also increasing. We used Mendelian randomization to examine whether uric acid is an independent and causal cardiovascular risk factor. Serum uric acid was measured in 3315 patients of the Ludwigshafen Risk and Cardiovascular Health Study. We calculated a weighted genetic risk score (GRS) for uric acid concentration based on eight uric acid–regulating single nucleotide polymorphisms. Causal odds ratios and causal hazard ratios (HRs) were calculated using a two-stage regression estimate with the GRS as the instrumental variable to examine associations with cardiometabolic phenotypes (cross-sectional) and mortality (prospectively) by logistic regression and Cox regression, respectively. Our GRS was not consistently associated with any biochemical marker except for uric acid, arguing against pleiotropy. Uric acid was associated with a range of prevalent diseases, including coronary artery disease. Uric acid and the GRS were both associated with cardiovascular death and sudden cardiac death. In a multivariate model adjusted for factors including medication, causal HRs corresponding to each 1-mg/dl increase in genetically predicted uric acid concentration were significant for cardiovascular death (HR, 1.77; 95% confidence interval, 1.12 to 2.81) and sudden cardiac death (HR, 2.41; 95% confidence interval, 1.16 to 5.00). These results suggest that high uric acid is causally related to adverse cardiovascular outcomes, especially sudden cardiac death.  相似文献   
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