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61.
The effect of two oral doses (10 and 20 mg) of nifedipine versus placebo on the fasted gallbladder volume and on the meal-induced gallbladder emptying was assessed according to a double-blind study protocol in 12 healthy volunteers. Eight subjects underwent three studies (with placebo and with both nifedipine doses), whereas in two subjects the effect of a 10-mg nifedipine dose, vs placebo and in two others the effect of a 20-mg nifedipine dose vs placebo was examined. The studies were performed on separate days, and the gallbladder volume was measured by means of real-time ultrasonography. Neither placebo nor 20 mg nifedipine per os elicited any significant change in the fasted gallbladder vlume. With 10 mg nifedipine per os a significant increase in the interdigestive gallbladder volume was observed: 22.9±2.9 cm3 before and 26.2±3.2 cm3 after the drug receipt (P<0.005). A trend towards an inhibition of the postprandial gallbladder emptying was observed with 10 mg nifedipineper os without, however, reaching the level of statistical significance. Following 20 mg nifedipineper os, a marked delay in the meal-stimulated gallbladder emptying occurred as reflected by a decrease in the gallbladder ejection fraction from 48.1±4.5% (placebo) to 26.4±5.0% (nifedipine) (P<0.02) at 30 min and from 54.0±3.6% (placebo) to 33.2±4.6% (nifedipine) (P<0.02) at 40 min after the test meal. We conclude that a therapeutic oral dosage of nifedipine has a significant relaxing effect on the human gallbladder.  相似文献   
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Hemorrhagic stroke is a frequent cause of morbidity and mortality in Poland. It results from disruption of intracranial vessel wall continuity. We report a case of 66-years-old man with prosthetic aortic valve after three ischemic strokes treated with acenocoumarol who was admitted to hospital with vertigo and motoric aphasia. Computed tomography confirmed a hemorrhagic stroke related to anticoagulant treatment. We discussed the principles of management and therapeutic options in patients requiring long-term anticoagulation suffering from severe hemorrhagic complications.  相似文献   
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BACKGROUND: The coexistence of peripheral artery disease (PAD) and multilevel atherosclerosis increases death and stroke rates in patients with coronary artery disease (CAD). Due to many comorbidities these patients are often treated conservatively without revascularisation. AIM: To investigate whether complex percutaneous cardiovascular interventions for CAD and PAD may improve prognosis and long-term outcome in this group of patients. METHODS: We studied consecutive patients treated for symptomatic CAD who also had chronic PAD. The primary cause of hospital admission for all our patients was non-ST elevation acute coronary syndrome (NSTE ACS). All percutaneous peripheral interventions were performed during one hospital stay (index hospitalisation). Major adverse cardio- and cerebrovascular events (MACCE) during follow-up were defined as follows: death (cardiac and non-cardiac), myocardial infarction (MI), urgent revascularisation (surgical or repeat PCI, peripheral percutaneous intervention), stroke/TIA or amputation. RESULTS: We performed 109 interventions in 78 consecutive patients with chronic peripheral artery stenoses and occlusions. The average age was 61.5+/-8.6 years and the majority were males (80%). Preinterventional angiography showed occlusions that involved the common iliac artery in 28 (36%) patients, the external iliac artery in 16 (21%) patients, internal iliac artery in 2 (3%) patients, and superficial femoral artery in 63 (81%) patients. Stenting was performed in half of the patients with a mean stent length of 69.6+/-50.3 mm. An average number of 1.24+/-0.55 stents was used for each lesion. During a mean follow-up of 18 months (range 4 to 42), there were 4 deaths, 3 MIs, 13 repeated percutaneous peripheral interventions due to restenosis in previously treated peripheral lesions, two urgent coronary interventions, two ischaemic strokes, two TIAs and one amputation. The combined follow--up MACCE end-point occurred in 32% of patients. CONCLUSIONS: Patients with concomitant CAD and PAD could safely undergo percutaneous cardiovascular and peripheral interventions. Multilevel intervention is associated with a promising long-term follow-up.  相似文献   
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OBJECTIVES: The purpose of the study was to evaluate the role of insulin resistance (IR) in the development of coronary atherosclerosis in patients with impaired glucose tolerance. METHODS AND RESULTS: The study group consisted of 42 patients with impaired glucose tolerance. Based upon coronary angiography the patients were divided into group A--with prior myocardial infarction and critical coronary stenosis (n=20) and group B--without prior myocardial infarction and without critical coronary stenosis (n=22). In each patient glucose disposal rate (GDR) during metabolic clamp, insulinaemia in the fasting state and during the clamp, glycaemia during oral glucose tolerance test (OGTT), BMI and body mass composition were measured. The groups did not differ in age, BMI, percent fat content and distribution, and blood pressure. Fasting insulinaemia (56.7 microU/ml) was higher in group A than in group B (22.3 microU/ml). GDR in group A (2.96 mg/kg b.m./min) was lower than in group B (5.36 mg/kg b.m./min). There was a negative correlation between the number of critically narrowed coronary vessels and GDR in group A. GDR below 3.97 mg/kg b.m./min was found, based on regression analysis, to be a powerful risk factor for myocardial infarction. CONCLUSIONS: The relationship between IR and severity of coronary atherosclerosis implies its unfavourable role in the development of atherosclerosis. The present findings indicate a negative role of IR in the development of myocardial infarction and suggest that it is an independent risk factor, which identifies high-risk patients requiring treatment that would increase tissue insulin sensitivity.  相似文献   
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The paper presents the results of research concerning three fiber materials—mineral wool, hemp fiber and wood wool—as loose-fill thermal insulation materials. The analysis used the material parameters determined in previous works conducted by the authors, such as thermal conductivity and air permeability in relation to bulk density. These materials exhibit open porosity; thus, convection is an essential phenomenon in the heat transfer process. The paper aimed at conducting thermal simulations of various frame wall variants which were filled with the above-mentioned insulation materials. The simulations were performed with the Control Volume Method using the Delphin 5.8 software. The studies accounted for the effect of wind pressure and the time of its influence on a wall insulated by means of fiber material with a thickness of 150 as well as 250 mm. The simulation enabled us to obtain such data as maximal R-value reduction and time to return to equilibrium after filtration for the analyzed materials. The study proved that heat transfer in these insulations strongly depends on the bulk density, thickness of the insulation and wind pressure. The decrease in R is reduced as the density increases. This results from the decreased air permeability characterizing the material. Wind washing causes lower R reduction than air filtration in all models. The greater the thickness, the longer it takes for the models to return to the equilibrium state following air filtration (and wind washing). This period is comparable for air filtration and wind washing. Hemp fibers were characterized with the strongest susceptibility to air filtration; in the case of wood wool, it was also high, but lower than for hemp fibers, while mineral wool was characterized with the lowest.  相似文献   
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In order to determine the frequency of microtubule-associated protein tau gene (MAPT) mutations and rare variants in CBD, we performed a systematic sequence analysis of MAPT coding and 3′ untranslated region (3′UTR) in a large cohort of autopsy-confirmed CBD patients (N = 109). This identified a novel MAPT mutation in exon 13, p.N410H, in a case that is neuropathologically indistinguishable from sporadic CBD. On immunoblot, the p.N410H mutation carrier had the same insoluble tau profile as seen in CBD. Additionally, tau expression analysis in brain tissue found a significant increase in the 4R/3R tau mRNA ratio (P = 0.04), indicating that p.N410H disrupts tau isoform homeostasis. Biochemically, recombinant tau protein with p.N410H showed a marked increase in tau filament formation compared to wild-type tau (P < 0.001), had a 19.2 % decrease in rate of microtubule assembly (P < 0.05), and a 10.3 % reduction in the extent of total microtubule polymerization (P < 0.01). Sequence analysis of the complete MAPT 3′UTR in autopsy-confirmed CBD cases further identified two rare variants with nominally significant association with CBD. An ATC nucleotide insertion (“MAPTv8”) was found in 4.6 % of CBD patients compared to 1.2 % of controls (P = 0.031, OR = 3.71), and rs186977284 in 4.6 % CBD patients, but only 0.9 % of controls (P = 0.04, OR = 3.58). Rs186977284 was also present in 2.7 % of a large cohort of autopsy-confirmed PSP patients (N = 566) and only 0.9 % of an additional control series (P = 0.034, OR = 3.08), extending the association to PSP. Our findings show that mutations in MAPT can cause CBD and MAPT non-coding variants may increase the risk of complex 4R tauopathies.  相似文献   
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