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We compared the effects of oral administration of high-dose or low-dose glutamine dipeptide (GDP), alanine (ALA), glutamine (GLN), and ALA + GLN on the blood availability of amino acids in rats submitted to insulin-induced hypoglycemia (IIH). Insulin detemir (1 U/kg) was intraperitoneally injected to produce IIH; this was followed by oral administration of GDP, GLN + ALA, GLN, or ALA. We observed higher blood levels of GLN, 30 min after oral administration of high-dose GDP (1000 mg/kg) than after administration of ALA (381 mg/kg) + GLN (619 mg/kg), GLN (619 mg/kg), or ALA (381 mg/kg). However, we did not observe the same differences after oral administration of low-dose GDP (100 mg/kg) compared with ALA (38.1 mg/kg) + GLN (61.9 mg/kg), GLN (61.9 mg/kg), or ALA (38.1 mg/kg). We also observed less liver catabolism of GDP compared to ALA and GLN. In conclusion, high-dose GDP promoted higher blood levels of GLN than oral ALA + GLN, GLN, or ALA. Moreover, the lower levels of liver catabolism of GDP, compared to ALA or GLN, contributed to the superior performance of high-dose GDP in terms of blood availability of GLN.  相似文献   
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A 49-year-old woman was hospitalized for acute left foot arterial ischemia. Arterial Doppler revealed occlusion of the dorsalis pedis and posterior tibial arteries. A computed tomography angiography performed to assess abdominal pain showed hepatic, splenic, renal and pancreatic infarctions. A splenic artery embolism and a small aortic wall thrombus at the celiac trunk were identified. No radiological signs of aortic atherosclerosis were found. No predisposing conditions for secondary aortic thrombosis or intracardiac embolic sources were detected. It was determined that primary aortic thrombosis, a rare though potentially serious condition, was to blame. Isolated aortic mural thrombosis therapy is not well established, although systemic anticoagulation, thrombolysis, thromboaspiration, endovascular stent grafting and surgical thrombectomy have been attempted with varying success. In our patient, systemic anticoagulation therapy was initiated and resulted in aortic thrombus resolution. Close clinical follow-up is crucial, as the aortic thrombus can recur despite anticoagulation and aggressive control of the atherosclerotic risk factors.  相似文献   
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Aldehydes are highly reactive molecules, which can be generated during numerous physiological processes, including the biotransformation of drugs. Several non-P450 enzymes participate in their metabolism albeit alcohol dehydrogenase and aldehyde dehydrogenase are the ones most frequently involved in this process. Endogenous and exogenous aldehydes have been strongly implicated in multiple human pathologies. Their ability to react with biomacromolecules (e.g. proteins) yielding covalent adducts is suggested to be the common primary mechanism underlying the toxicity of these reactive species.  相似文献   
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Paracoccidioidomycosis is an acute - to chronic systemic mycosis caused by fungi of the genus Paracoccidioides. Due to its frequent tegument clinical expression, paracoccidioidomycosis is an important disease for dermatologists, who must be up-to-date about it. This article focuses on recent epidemiological data and discusses the new insights coming from molecular studies, as well as those related to clinical, diagnostic and therapeutic aspects. In the latter section, we give particular attention to the guideline on paracoccidioidomycosis organized by specialists in this subject.  相似文献   
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ObjectiveTo identify the urban phlebotomine sandfly fauna in Ponta Porã, Mato Grosso do Sul State, Brazil.MethodsThe captures were undertaken from April 2009 to March 2010 with CDC light traps in 14 ecotopes (intra and peridomicile) in different areas of the city, Shannon traps being used in areas with abundant vegetation.ResultsA total of 707 specimens were captured with CDC light traps (565 males and 142 females) and 155 specimens (112 males and 43 females) with Shannon traps, a total of 862 phlebotomines. The specimens captured belonged to eight species: Lutzomyia longipalpis (Lutz & Neiva, 1912), Evandromyia cortelezzii (Brethes, 1923), Sciopemyia sordelli (Shannon & Del Ponte, 1927), Pintomyia pessoai (Coutinho & Barretto, 1940); Pintomyia monticola (Costa Lima, 1932); Brumptomyia brumpti (Larousse, 1920); Nyssomyia whitmani (Antunes & Coutinho, 1939) and Psathyromyia shannoni (Dyar, 1929). Lutzomyia longipalpis, the main vector of Leishmania (Leishmania) chagasi, was the species most frequently captured (97.03%) and also the most abundant according to the standardized abundance index (SAI)=0.86.ConclusionsThe highest species richness was captured, with CDC light traps, inside the domiciles and the species diversity and evenness in the peridomicile, clearly indicating a preference for anthropic environments.  相似文献   
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The present paper contrasted categorical and featural hypotheses of semantic memory organisation in relation to the living/nonliving things dissociation phenomenon. In the three experiments reported, normal subjects decided if word pairs representing living, nonliving, or both (mixed pairs) shared a particular perceptual (i.e., four legs, size, and hardness) or functional attribute (i.e., dangerousness, speed, and usefulness). The overall pattern of results is more in accordance with a general featural perspective and also emphasises the role of functional attributes. Both a categorical perspective and an attribute-category connection hypothesis have more difficulties in explaining the observed data. Implications for the study of semantic memory organisation and for the explanation of living/nonliving things dissociation cases are also considered.  相似文献   
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