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In April 2004, two patients were admitted to hospital in Berlin, Germany, with clinical signs of acute respiratory infection after returning from a military exercise in their home country of Turkey. They were admitted to a high security infectious disease unit as epidemiological data pointed to an outbreak of unknown etiology. Samples taken at the time of admission proved to be strongly positive for Adenovirus by PCR, but negative for Influenza A/H1N1 virus, Influenza A/H3N2 virus, Influenza B virus, Respiratory syncytial virus, and SARS coronavirus. No evidence for bacterial infection was obtained by serological tests and blood cultures. The adenovirus detected was characterized further by genotyping and was identified as a species B2 virus with the highest similarity to adenovirus type 11a.  相似文献   
945.
Compared with lowland species, fetal life for mammalian species whose mothers live in high altitude is demanding. For instance, fetal llamas have to cope with the low fetal arterial PO2 of all species, but also the likely superimposition of hypoxia as a result of the decreased oxygen environment in which the mother lives in the Andean altiplano. When subjected to acute hypoxia the llama fetus responds with an intense peripheral vasoconstriction mediated by alpha-adrenergic mechanisms plus high plasma concentrations of catecholamines and neuropeptide Y (NPY). Endothelial factors such as NO and endothelin-1 also play a role in the regulation of local blood flows. Unlike fetuses of lowland species such as the sheep, the llama fetus shows a profound cerebral hypometabolic response to hypoxia, decreasing cerebral oxygen consumption, Na–K-ATPase activity and temperature, and resulting in an absence of seizures and apoptosis in neural cells. These strategies may have evolved to prevent hypoxic injury to the brain or other organs in the face of the persistent hypobaric hypoxia of life in the Andean altiplano.  相似文献   
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Neither macroscopic nor microscopic lesions were observed in the gastrointestinal mucosa following the surgical removal of Brunner's glands. This observation leaves some doubt concerning the traditional view that Brunner's glands function primarily in the protection of the proximal duodenal mucosa from acid-pepsin entering from the stomach.  相似文献   
949.
Development of the pituitary in Didelphis follows the general pattern of that described for most mammalian species. The dorsal region of a multichambered pituitary vesicle, which forms from Rathke's pouch, comes to lie adjacent to the presumptive infundibulum by the 10 1/2 d of gestation. The epithelial wall of this vesicle consists of spindle-shaped cells. The dorsal wall of the upper chamber of the pituitary vesicle forms the pars intermedia; the ventral wall of this chamber gives rise to cells of the pars distalis. Corticotropes, somatotropes, and lactotropes are seen in the presumptive adenohypophysis of the 11 1/2 d embryo. Gonadotropes and thyrotropes appear about 1 d later, shortly after birth. By the 2 postnatal week, the adult distribution of all 5 cell types within the pars distalis appears to have been established. The wall bounding the pituitary cleft in the adult represents an epithelial continuum limited by a basal lamina and corresponds to the upper chamber of the original pituitary vesicle. Ultrastructurally, the limiting walls of the pituitary cleft consists of stellate (marginal) cells, large, bulbous cells, and granulated cells. The latter correspond to the various endocrine cell types normally associated with the pars distalis. Non-granular folliculo-stellate cells also are observed within the epithelial cords of the pars distalis.  相似文献   
950.
Summary The aim of the study was to investigate the influence of 40 mg of the beta-blocker penbutolol (BetapressinTM; Hoechst Ltd., Frankfurt/ Main) in comparison to placebo on the insulin consumption on the blood sugar profile in twelve insulin-dependent diabetes (IDDM) patients. The patients were treated with penbutolol and placebo for a period of three days, and then were examined with the help of the glucose-controlled insulin infusion system.The blood sugar profile and insulin consumption over a 24 hour period was not affected by either penbutolol or placebo, nor could any changes be measured in these parameters when measured after food intake.After a submaximal exercise load on the bicycle ergometer (1 watt per kg body weight) following an evening meal, no difference could be observed between penbutolol and placebo in the above-mentioned parameters. The same was also true for hormonal parameters as STH, ACTH, cortisol, and catecholamines.These findings demonstrated that medication of penbutolol over a three-day period has no influence on the baseline blood sugar profile and insulin consumption or on insulin consumption after food intake during rest and physical exercise.Abbreviations IDDM insulin-dependent diabetes - STH somatotropic hormone - GH growth hormone - ACTH adrenocorticotropic hormone - HbA1 glycosylated hemoglobin A1 - mE milli-units - SEM standard error of the mean  相似文献   
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