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OBJECTIVE: To compare myocardial concentrations of fatty acids in dogs with dilated cardiomyopathy (DCM) with concentrations in control dogs. SAMPLE POPULATION: Myocardial tissues from 7 dogs with DCM and 16 control dogs. PROCEDURE: Myocardial tissues were homogenized, and total fatty acids were extracted and converted to methyl esters. Myocardial concentrations of fatty acids were analyzed by use of gas chromatography and reported as corrected percentages. RESULTS: The amount of docosatetraenoic acid (C22:4 n-6) was significantly higher in myocardial samples from dogs with DCM (range, 0.223% to 0.774%; median, 0.451%), compared with the amount in samples obtained from control dogs (range, 0.166% to 0.621%; median, 0.280%). There were no significant differences between DCM and control dogs for concentrations of any other myocardial fatty acids. CONCLUSIONS AND CLINICAL RELEVANCE: Although concentrations of most myocardial fatty acids did not differ significantly between dogs with DCM and control dogs, the concentration of docosatetraenoic acid was significantly higher in dogs with DCM. Additional investigation in a larger population is warranted to determine whether this is a primary or secondary effect of the underlying disease and whether alterations in fatty acids may be a target for intervention in dogs with DCM.  相似文献   
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The reported incidence of clinical hepatitis E cases is rising in some non‐endemic countries, with concurrent concerns regarding potential hepatitis E virus (HEV) contamination of the blood supply. Therefore, the characterization of major potential sources of human HEV exposure is important to inform risk assessment and public health policy. A systematic review was conducted, including a comprehensive search in six electronic bibliographic databases, verified by hand‐searching reference lists of HEV reviews, and a grey literature search, of the broad research question ‘what is the evidence of the association between predictors of human HEV exposure, and HEV IgG seropositivity, in non‐endemic countries?’ Using forms designed a priori, captured studies were appraised at first‐level screening, second‐level characterization, and third‐level data extraction and risk of bias assessment. Meta‐analysis yielded summary estimates of association between potential predictors and odds of HEV seropositivity. Meta‐analysis and meta‐regression of the odds of HEV seroprevalence in specific groups characterized potential sources of HEV exposure. From 4,163 captured citations, 245 relevant studies underwent data extraction, investigating HEV seroprevalence or predictors in both healthy subjects and targeted patient groups. Across these groups, increasing age was a predictor of HEV IgG seropositivity. Both human immunodeficiency virus patients and haemodialysis patients had significantly increased odds of HEV seropositivity relative to the general population. Working with pigs, in forestry, or in hospitals, was significantly associated with increased odds of HEV seropositivity, as were consumption of meat, pork or game meat, or hunting. Chronological time was not associated with HEV seropositivity within our data sets. Further study of the distribution of potential dietary or behavioural predictors between high and lower prevalence areas within non‐endemic countries could improve our understanding of the relative importance of specific HEV transmission pathways.  相似文献   
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Fifty-five dogs received packed red blood cell (PRBC) transfusions for gastrointestinal (GI) hemorrhage during a 26-month period (1999 to 2001), accounting for 11.7% of the PRBC transfusions in that time. Thirty-nine (61%) dogs had an intestinal pathology (primary or secondary) as the cause of GI hemorrhage, including intestinal masses, gastroenteritis, hepatic disease, and renal disease. Nonsteroidal and steroidal anti-inflammatory drug use was found frequently in dogs with GI hemorrhage. Sixteen (39%) dogs were identified as having immune-mediated thrombocytopenia (IMT) and associated GI hemorrhage. Dogs with IMT received more transfusions of PRBC than nonIMT dogs (P<0.03) and received a significantly larger total volume of PRBC (P<0.01) during hospitalization.  相似文献   
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Endoscopy is generally a very safe and effective tool in the diagnosis and therapy of various gastrointestinal (GI) disorders, and must be used in conjunction with other diagnostic modalities. Endoscopy should not be a substitute for a complete work-up. There are many advantages of endoscopy, including minimal morbidity and mortality, and the sensitivity of this modality in the diagnosis of mucosal disorders of the GI tract. However, complications may occur, and there are limitations to endoscopy. This article will provide an overview of when to choose GI endoscopy and when other procedures might provide more information.  相似文献   
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