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31.
Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against -amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthdayPresented in part at the Second International Symposium on the Classification of Pancreatitis, Marseille, 1984, and at the Meeting of the European Pancreatic Club, Manchester, 1985  相似文献   
32.
The trisomy 16 mouse model of Down syndrome has been used to compare calcium (Ca)-homeostasis and Ca-signaling in astrocytes from trisomic mice and from diploid littermates. Ratio calcium-imaging of Fura-2/AM loaded primary astroglial cultures prepared from the hippocampus shows that resting Ca levels are on average significantly higher in trisomic than in the control astrocytes (280 vs. 120 nM). Serotonin (3 μM) and glutamate (30–300 μM) evoked transient Ca-increases from 400 to 600 nM in euploid but from only 20 to 150 nM in trisomic astrocytes. Imaging of ATP-driven Ca-accumulation in cellular organelles revealed a significantly stronger uptake of Ca in trisomic astrocytes that might buffer cytosolic Ca-increases. Our results demonstrate major disturbances in Ca-signaling in trisomic astrocytes that are likely to be of pathophysiological relevance.  相似文献   
33.
Ventromedial hypothalamic lesioned rats maintained at preoperative body weight received an equal number of shocks while emitting significantly fewer responses than controls in a lever-pressing free-operant avoidance paradigm, and performed as well as unoperated animals in lever-pressing and shuttle box (both 1- and 2-way) discriminated avoidance tasks. The failure of VMH lesions to facilitate performance in the 2-way avoidance paradigm was probably the result of a ceiling effect. With the exception of the simple one-way avoidance task, obese lesioned rats were markedly impaired in the acquisition of all active avoidance behavior, but escape behavior was not affected. When tested in a free-operant paradigm, the avoidance performance of well trained lesioned animals varied inversely with body weight. As obese rats displayed lower flinch thresholds to shock than controls and similar levels of activity and responding as lean lesioned animals, it was concluded that their impaired avoidance behavior was not due to changes in sensitivity or mobility. The possible relation to other VMH lesion- and/or obesity-induced deficits is discussed.  相似文献   
34.
Advances in Health Sciences Education - Dyslexia is a Specific Learning Difficulty that impacts on reading and writing abilities. During the COVID-19 pandemic, medical schools have been forced to...  相似文献   
35.
Our aim was to assess the association between a priori defined dietary patterns and incident depressive symptoms. We used data from The Maastricht Study, a population-based cohort study (n = 2646, mean (SD) age 59.9 (8.0) years, 49.5% women; 15,188 person-years of follow-up). Level of adherence to the Dutch Healthy Diet (DHD), Mediterranean Diet, and Dietary Approaches To Stop Hypertension (DASH) were derived from a validated Food Frequency Questionnaire. Depressive symptoms were assessed at baseline and annually over seven-year-follow-up (using the 9-item Patient Health Questionnaire). We used Cox proportional hazards regression analyses to assess the association between dietary patterns and depressive symptoms. One standard deviation (SD) higher adherence in the DHD and DASH was associated with a lower hazard ratio (HR) of depressive symptoms with HRs (95%CI) of 0.78 (0.69–0.89) and 0.87 (0.77–0.98), respectively, after adjustment for sociodemographic and cardiovascular risk factors. After further adjustment for lifestyle factors, the HR per one SD higher DHD was 0.83 (0.73–0.96), whereas adherence to Mediterranean and DASH diets was not associated with incident depressive symptoms. Higher adherence to the DHD lowered risk of incident depressive symptoms. Adherence to healthy diet could be an effective non-pharmacological preventive measure to reduce the incidence of depression.  相似文献   
36.
Changes in intestinal microbiome and barrier function are critical in the development of alcohol-related liver disease (ALD). Here, we determined the effects of a one-week alcohol withdrawal on parameters of intestinal barrier function in heavy drinkers with ALD in comparison to healthy non-drinkers (controls). In serum samples of 17 controls (m = 10/f = 7) and 37 age-matched ALD patients (m = 26/f = 11) undergoing a one-week alcohol withdrawal, markers of liver health and intestinal barrier function were assessed. Liver damage, e.g., fibrosis and hepatic steatosis, were assessed using FibroScan. Before alcohol withdrawal, markers of liver damage, lipopolysaccharide binding protein (LBP) and overall TLR4/TLR2 ligands in serum were significantly higher in ALD patients than in controls, whereas intestinal fatty acid binding protein (I-FABP) and zonulin protein concentrations in serum were lower. All parameters, with the exception of LBP, were significantly improved after alcohol withdrawal; however, not to the level of controls. Our data suggest that one-week of abstinence improves markers of intestinal barrier function and liver health in ALD patients.  相似文献   
37.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss...  相似文献   
38.
The European Journal of Health Economics - The transferability of the EU joint clinical assessment (JCA) reports for pharmaceuticals for the German benefit assessment was evaluated by...  相似文献   
39.
International Urology and Nephrology - To assess the efficacy of prophylaxis for urinary tract infections (UTI) in a two-year follow-up in women with StroVac compared to a therapy with...  相似文献   
40.
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