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Heat stroke is a lifethreatening disease with high mortality, characterized by a body temperature of over 40°C and clinical symptoms of central nervous system dysfunction. However, the pathophysiological mechanisms are not fully understood. A new interesting explanation for the clinical symptoms could be a systemic inflammatory response due to barrier dysfunction in the intestine leading to endothelial damage and a syndrome of multiorgan dysfunction. We describe a 37-year-old male patient who collapsed while working in a vineyard in an environmental temperature of 32°C with a body temperature of 42.5°C. Despite intensive care treatment, he died with symptoms of shock and multiorgan dysfunction. Autopsy was performed followed by the histological evaluation of paraffin-embedded tissue. As correlates for clinical shock symptoms, shock kidneys and shock liver could be demonstrated. Furthermore, multiple microthrombi were found, together with clinically undetectable fibrinogen values. Finally, the patient died due to massive diffuse gastrointestinal bleeding and bleeding in pleural and pericardial cavities. No signs of severe edema of the central nervous system were detectable. This case supports the hypothesis that in heat stroke endothelial damage occurs with consecutive cascade of inflammatory and coagulatory reactions, which may play a critical pathophysiological role.  相似文献   
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Purified rhodopsin was incorporated into phospholipid bilayers of egg phosphatidylcholine to give recombinant membrane vesicles, which were examined by proton and phosphorus nuclear magnetic resonance spectroscopy. Increased rhodopsin content in the membranes appears to progressively inhibit the molecular motions of the methyl, methylene, and phosphate groups of the phospholipid molecules. This indicates that regions of the rhodopsin molecule interact in a manner that affects the phospholipids from the aqueous interface to the bilayer midline. In the dark, the recombinant vesicles were sealed to europium, manganese, or cobalt ions. Light exposure allowed rapid equilibration of Mn2+ and Co2+, and somewhat slower equilibration of Eu3+ across the membrane. Light changed the membrane permeability, and the gradient in chemical potential resulted in a net ion movement across the rhodopsin:phospholipid recombinant membrane. The results suggest rhodopsin is a transmembrane protein.  相似文献   
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The objective of this study was to investigate the prognostic significance of the ambulatory blood pressure (BP) during night and day and of the night-to-day BP ratio (NDR). We studied 7458 participants (mean age 56.8 years; 45.8% women) enrolled in the International Database on Ambulatory BP in relation to Cardiovascular Outcome. Using Cox models, we calculated hazard ratios (HR) adjusted for cohort and cardiovascular risk factors. Over 9.6 years (median), 983 deaths and 943 cardiovascular events occurred. Nighttime BP predicted mortality outcomes (HR, 1.18-1.24; P<0.01) independent of daytime BP. Conversely, daytime systolic (HR, 0.84; P<0.01) and diastolic BP (HR, 0.88; P<0.05) predicted only noncardiovascular mortality after adjustment for nighttime BP. Both daytime BP and nighttime BP consistently predicted all cardiovascular events (HR, 1.11-1.33; P<0.05) and stroke (HR, 1.21-1.47; P<0.01). Daytime BP lost its prognostic significance for cardiovascular events in patients on antihypertensive treatment. Adjusted for the 24-h BP, NDR predicted mortality (P<0.05), but not fatal combined with nonfatal events. Participants with systolic NDR of at least 1 compared with participants with normal NDR (> or = 0.80 to <0.90) were older, at higher risk of death, but died at higher age. The predictive accuracy of the daytime and nighttime BP and the NDR depended on the disease outcome under study. The increased mortality in patients with higher NDR probably indicates reverse causality. Our findings support recording the ambulatory BP during the whole day.  相似文献   
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BACKGROUND: To assess the impact of immediate versus delayed antihypertensive treatment on the outcome of older patients with isolated systolic hypertension, we extended the double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial by an open-label follow-up study lasting 4 years. METHODS: The Syst-Eur trial included 4695 randomized patients with minimum age of 60 years and an untreated blood pressure of 160-219 mmHg systolic and below 95 mmHg diastolic. The double-blind trial ended after a median follow-up of 2.0 years (range 1-97 months). Of 4409 patients still alive, 3517 received open-label treatment consisting of nitrendipine (10-40 mg daily) with the possible addition of enalapril (5-20 mg daily), hydrochlorothiazide (12.5-25 mg daily), or both add-on drugs. Non-participants (n = 892) were also followed up. RESULTS: Median follow-up increased to 6.1 years. Systolic pressure decreased to below 150 mmHg (target level) in 2628 participants (75.0%). During the 4-year open-label follow-up, stroke and cardiovascular complications occurred at similar frequencies in patients formerly randomized to placebo and those continuing active treatment. These rates were similar to those previously observed in the active-treatment group during the double-blind trial. Considering the total follow-up of 4695 randomized patients, immediate compared with delayed antihypertensive treatment reduced the occurrence of stroke and cardiovascular complications by 28% (P = 0.01) and 15% (P = 0.03), respectively, with a similar tendency for total mortality (13%, P = 0.09). In 492 diabetic patients, the corresponding estimates of long-term benefit (P < 0.02) were 60, 51 and 38%, respectively. CONCLUSIONS: Antihypertensive treatment can achieve blood pressure control in most older patients with isolated systolic hypertension. Immediate compared with delayed treatment prevented 17 strokes or 25 major cardiovascular events per 1000 patients followed up for 6 years. These findings underscore the necessity of early treatment of isolated systolic hypertension.  相似文献   
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The aim of this article is to provide an inventory of the use of contrast‐enhanced ultrasound (CEUS) in relation to percutaneous interventional procedures. The article is structured into a systematic literature review followed by a clinical part relating to percutaneous CEUS‐guided procedures. A literature search identified 3109 records. After abstract screening, 55 articles were analyzed and supplemented with pictorial material to explain the techniques. In conclusion, the best‐evidenced indications for CEUS‐guided interventions are biopsy and ablation of inconspicuous or B‐mode–invisible tumors, intraprocedural ablation control and follow‐up, as well as percutaneous transhepatic cholangiography and drainage procedures.  相似文献   
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