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1.
The effect of glucose infusion on renal handling of purine bases and oxypurinol was examined in 6 normal subjects. Five hundred milliliters of 1.1 M glucose solution were administered intravenously in 1 h. Fractional clearances of uric acid, xanthine and oxypurinol were significantly increased during glucose infusion, but that of hypoxanthine was not changed, while a 1-hour infusion of 500 ml of 1.1 M mannitol had no effect on the fractional clearances of purine bases and oxypurinol. These data indicate that the effect of glucose infusion on the renal clearances of uric acid, xanthine and oxypurinol was not related to osmotic diuresis but induced by glycosuria and/or hyperglycemia. Accordingly, the glycosuria- and/or hyperglycemia-induced decrease in the biological half-life of oxypurinol must be considered in the administration of allopurinol to gouty patients with uncontrolled diabetes mellitus.  相似文献   

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PURPOSE: To describe the percutaneous treatment of an orbital hydatid cyst as an alternative approach to conventional surgery. METHODS: In a 21-year-old man with diplopia and right proptosis, radiologic studies disclosed a 25 x 25 x 20-mm purely cystic mass in the right retrobulbar area. Based on the presumptive diagnosis of hydatid cyst, the cyst was treated percutaneously under ultrasonographic guidance with aspiration, 15% hypertonic saline injection, and reaspiration without any complication. RESULTS: A substantial decrease in the size of the cyst was observed in the 3 months after treatment. Nine months after treatment, the shrunken cyst had a volume of only 0.5 ml, and the patient was asymptomatic. Twenty-one months after the procedure, the findings were consistent with those at 9 months of follow-up. CONCLUSION: Percutaneous treatment of orbital hydatid cysts, which is more satisfactory to both the patient and the physician, may be a safe and effective alternative to surgical extirpation.  相似文献   

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Two different mitochondrial genes, the cytochrome b and the 16S rDNA, support the same European cyprinid molecular phylogeny: the most basal subfamily is the paraphyletic Rasborinae, the Cyprininae are monophyletic, the Tincinae and Gobioninae are close to the Cyprininae or more basal lineages but not close to Leuciscinae or Alburninae, and the Leuciscinae are paraphyletic but can become monophyletic if we include the biphyletic alburninae and exclude the Phoxinini. The relationship of the Acheilognathinae remains obscure. Natural intergeneric and interspecific hybridizations are clearly demonstrated within the Leuciscinae, both from high bootstrap proportions and intermediate morphological features: Chondrostoma toxostoma and Rutilus rutilus, Scardinius erythrophthalmus and R. rutilus, and Leuciscus multicellus and Leuciscus soufia. Finally, the use of the nonsaturated and clockwise 16S mtDNA sequences have been used to infer from nonintrogressive taxa the time of the first European cyprinid cladogeneses. The estimation confirms the hypothesis of Alma?a and Banarescu that European cyprinid subfamilies started to diversify 35 mya and confirms the hypothesis of Bianco on the diversification of European leuciscines in the Mediterranean area during the late Messinian (6.5 to 5.3 mya).  相似文献   

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Evidence for a clade of nematodes, arthropods and other moulting animals   总被引:2,自引:0,他引:2  
The arthropods constitute the most diverse animal group, but, despite their rich fossil record and a century of study, their phylogenetic relationships remain unclear. Taxa previously proposed to be sister groups to the arthropods include Annelida, Onychophora, Tardigrada and others, but hypotheses of phylogenetic relationships have been conflicting. For example, onychophorans, like arthropods, moult periodically, have an arthropod arrangement of haemocoel, and have been related to arthropods in morphological and mitochondrial DNA sequence analyses. Like annelids, they possess segmental nephridia and muscles that are a combination of smooth and obliquely striated fibres. Our phylogenetic analysis of 18S ribosomal DNA sequences indicates a close relationship between arthropods, nematodes and all other moulting phyla. The results suggest that ecdysis (moulting) arose once and support the idea of a new clade, Ecdysozoa, containing moulting animals: arthropods, tardigrades, onychophorans, nematodes, nematomorphs, kinorhynchs and priapulids. No support is found for a clade of segmented animals, the Articulata, uniting annelids with arthropods. The hypothesis that nematodes are related to arthropods has important implications for developmental genetic studies using as model systems the nematode Caenorhabditis elegans and the arthropod Drosophila melanogaster, which are generally held to be phylogenetically distant from each other.  相似文献   

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IDDM is a polygenic and autoimmune disorder in which subsets of white blood cells (WBCs) are engaged in the destruction of beta-cells of the pancreas. The mechanisms that account for the abnormal behavior of these cells in IDDM are not fully understood. By measuring the mean length of telomeres of WBCs from patients with IDDM, we tested the concept that telomeres might play a role in IDDM. We examined the lengths of the terminal restriction fragments (TRFs) of DNA of WBCs from 234 white men comprising 54 patients with IDDM, 74 patients with NIDDM, and 106 control subjects. When adjusted for age, the TRF length from WBCs of patients with IDDM was significantly shorter than that of nondiabetic control subjects (mean +/- SE: 8.6 +/- 0.1 vs. 9.2 +/- 0.1, P = 0.002). No significant difference was observed between the TRF length from WBCs of patients with NIDDM versus nondiabetic subjects. Neither the duration nor the complications of IDDM (i.e., nephropathy and hypertension) had an effect on the TRF length of WBCs from patients with IDDM. The shortened TRF length of WBCs of patients with IDDM likely reflects a marked reduction in the TRF length of subsets of WBCs that play a role in the pathogenesis of IDDM.  相似文献   

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In this paper it is proposed that it is both meaningful and socially relevant to view ethnic stereotypes as beliefs generally shared in the community about characteristics of various groups. The implications of this traditional approach are discussed. The argument is also made, however, that traditional assessment procedures do not readily permit the measurement of individual differences in the tendency to adopt stereotypes and thus do not allow for the investigation of stereotyping as a process. An alternative measurement procedure is described, and its applications to study a number of aspects of the stereotyping process are summarized. Research bearing on the consequences on ethnic stereotypes viewed as consensual beliefs is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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A new transdiaphragmatic laparoscope technique is proposed which provides a large window for drainage that is rapid, safe and eliminates the need for one lung ventilation, drainage tubes, and painful incisions.  相似文献   

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The phosphatidylinositolphosphate kinases (PIPkins) are a unique family of enzymes that catalyse the production of phosphorylated inositol lipids. Recent advances have revealed that, due to their ability to utilise a number of different lipid substrates (at least in vitro), this family is potentially able to generate several distinct, physiologically important inositol lipids. Despite their importance, however, our understanding of the regulation of the PIPkins and of their physiological role in cellular signalling and regulation is still poor. Here we describe in turn the diverse physiological functions of the known substrates and major products of the PIPkins. We then examine what is known about the members of the PIPkin family themselves, and their characteristics and regulation.  相似文献   

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The problem of finding least-cost reconstructions of past host/parasite associations, given the phylogenetic histories of a set of host taxa and of their associated parasites, is known to be complex. I provide in this article a new method of implicitly listing all the potentially optimal solutions to the problem, by considering each hypothesised past association individually, in a structure I have termed a Jungle. These structures are demonstrated to enable fast acquisition of globally optimal solutions under general weighting schemes, including minimisation of total number of postulated events and maximization of postulated cospeciation events. A simple example is given, and the pocket gopher/chewing louse system investigated by Hafner and Nadler [Hafner and Nadler, Nature 332 (1988) 258] is re-examined.  相似文献   

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The etiology of seizures associated with cocaine use is unclear. Because cocaine seizures are relatively uncommon, they should be diagnosed by exclusion and a neurological workup to rule out central nervous system (CNS) catastrophe should be made. This report describes the clinical findings, treatment, and blood cocaine and metabolite concentrations in a patient who, on two separate occasions, had seizures associated with crack cocaine ingestion. Approximately 1 hour after the ingestion incidents, the patient had multiple, generalized seizures that abated spontaneously. His workup for CNS bleeding, infection, and trauma was negative. Cocaine concentrations on the first incident peaked at 2.48 mg/L and on the second incident peaked at 3.9 mg/L. Other clinical findings included tachycardia, hypertension, diaphoresis, and disorientation. Blood cocaine and metabolite analysis revealed extremely high concentrations. Other than the incident of seizures and transient cardiovascular aberrations, these high concentrations were tolerated by the patient without further sequelae. A review of cocaine-induced seizures and treatment is included.  相似文献   

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The diffuse nature of arterial occlusions in Buerger's disease compromises the effect of revascularization. Nevertheless, the muscle branches are quite often unaffected by the occlusive disease making revascularization of collateral arterial branches a promising alternative to conventional procedures. Revascularization by a short autologous venous graft from the grand anastomotic or gastrocnemius artery can be an alternative technique. Advances in microsurgery have made such revascularizations possible.  相似文献   

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A new procedure is described for thoracic expansion in Jeune's asphyxiating dystrophy. The chest wall is enlarged by division of ribs and underlying tissue in a staggered fashion so that either rib or periosteum covers the lung. New bone formation has been demonstrated so that a viable enlargement has been obtained. The clinical result is excellent to date.  相似文献   

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A new technique for understanding the organization of complex circuits in the vertebrate brain, scanning laser photostimulation, is described. This approach is based on the photolysis of a caged form of the excitatory neurotransmitter glutamate. Computer-controlled photostimulation and whole cell recording in brain slices allow the construction of detailed maps of the position, strength, sign and number of inputs converging on a single postsynaptic neuron. Scanning laser photostimulation offers many advantages over current techniques: spatial resolution is superb, fibers of passage are not activated, and thousands of presynaptic locations can be stimulated. This review describes the technique of photostimulation, outlines the instrumentation, necessary to implement it, and discusses the interpretation of photostimulation-derived data. Several examples of applications, ranging from mapping circuits in the mammalian visual cortex to determining receptor distributions on single neurons are considered. Although still in its early stages, scanning laser photostimulation offers neuroscientists a powerful tool for determining the organization and function of local brain circuits.  相似文献   

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In a prospective study 102 patients with malignant tumors of the tongue, oropharynx, hypopharynx, and larynx were staged by means of MRI. Special attention was directed at those tumour extensions that could influence the treatment strategy. The MR findings were correlated with the results of palpation, endoscopy, ultrasound, computerised tomography and histopathological findings. MRI showed a good delineation of pT2 to pT4 tumours. However, visualisation of small tumours in the soft palate, the tonsils, the pyriform sinuses and vocal cords was difficult. In conclusion our results suggest that in addition to endoscopy MRI is a valuable tool for the examination of tumours of tongue, oropharynx, hypopharynx and larynx.  相似文献   

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