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The role of selected neuropeptides in pathogenesis of atopic dermatitis   总被引:1,自引:0,他引:1  
Background Atopic dermatitis (AD) is an inflammatory skin disease of a chronic course. The role of neuropeptides in pathogenesis of this disorder is probably not crucial; however, there is evidence that these substances influence the development and course of AD. Objective The aim of this study was to evaluate the plasma level of substance P, neuropeptide Y (NPY) and calcitonin gene related peptide (CGRP) in AD patients during exacerbation and remission of the disease. Material and methods Forty‐nine patients with AD, aged 17 to 56 years, participated in the study. Among this group, there were 25 males (51%) and 24 females (49%). The disease lasted from 1 to 55 years. The severity of the disease was assessed with SCORAD index. The severity of pruritus was evaluated with Visual Analog Scale and a specially designed questionnaire. Neuropeptides plasma level was detected with radioimmunoassay. Results Substance P plasma level in AD patients during exacerbation and remission was significantly higher than in the control group. There was a negative correlation between substance P plasma level and total IgE level. CGRP plasma level during exacerbation of AD was significantly lower than in healthy controls and increased in the remission. Significantly higher CGRP concentration was observed in patients suffering from severe pruritus; however, both in patients with more and less severe pruritus, CGRP plasma level was lower than in controls. Higher CGRP plasma level was also observed in patients with more severe disease. NPY plasma level in patients with AD was significantly increased both during exacerbation and remission. During remission of AD, NPY concentration was higher than during exacerbation.  相似文献   
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Silane treatment effects on glass/resin interfacial shear strengths.   总被引:1,自引:0,他引:1  
OBJECTIVE: Methacrylic resin-based dental composites normally use a bifunctional silane coupling agent with an intermediary carbon connecting segment to provide the interfacial phase that holds together the organic polymer matrix with the reinforcing inorganic phase. In this study, fiber pull-out tests were used to measure the interfacial bond strength at the fiber-matrix interface. METHODS: Glass fibers (approximately 30 microm diameter, 8 x 10 (-2)m length, MoSci) were silanated using various concentrations (1, 5 and 10%) of either 3-methacryloxypropyl-trimethoxysilane (MPS) or glycidoxypropyltrimethoxy-silane (GPS) in acetone (99.8%). Rubber (poly(butadiene/acrylonitrile), amine terminated, M(w) 5500) molecules were also attached to the fiber surface via GPS molecules. The resin was comprised of a 60/40 mixture of Bis-phenol-A bis-(2-hydroxypropyl)-methacrylate (BisGMA) and tri (ethylene glycol) dimethacrylate (TEGDMA). A bead of resin approximately 2-4 x 10(-3)m in embedded length was placed on the treated fibers and light cured. The load required to pull the fiber out of the resin was converted to shear bond strength. RESULTS: Interfacial shear strengths were greater for silanated specimens compared with unsilanated, and for MPS compared with GPS. The same set of samples soaked in 50:50 (v/v) mixtures of ethanol and distilled water for a period of 1 month showed a decrease in properties. SIGNIFICANCE: A positive correlation was found between the amount of silane on the filler surface and the property loss after soaking. Rubber treatment provided improvement in interfacial strength. 5% MPS samples had the highest strength both in soaked as well as unsoaked samples.  相似文献   
145.
Increased hypothalamic neuropeptide-Y (NPY) action and disruption of the melanocortin (MC)-4 receptor both result in hyperphagia and obesity. To determine whether similar hormonal and metabolic mechanisms are involved in these two obesity syndromes, we investigated the time course of effects induced by 6-day intracerebroventricular (ICV) infusion of NPY (3.5 nmol/day) or the MC4 receptor antagonist HS014 (4.8 nmol/day) in rats pair-fed with vehicle-infused controls. The weight of white adipose tissue (WAT) deposits was increased after 6-day NPY and HS014 infusion compared with controls, and the increase was significantly greater in HS014- than in NPY-infused rats (retroperitoneal WAT: NPY 0.57 +/- 0.05; HS014 0.80 +/- 0.05; control 0.43 +/- 0.03% body wt, n = 8-13, P < 0.05). Plasma leptin was also increased in both experimental groups (NPY 10.6 +/- 1.9; HS014 4.4 +/- 0.9; control 2.0 +/- 0.1 ng/ml, n = 8-13, P < 0.05 for all comparisons). Basal plasma corticosterone and insulin levels were increased by ICV NPY infusion, whereas HS014-infused rats showed no significant increase in these parameters on any of 1-6 days of infusion. Both NPY and HS014 infusion potentiated intravenous glucose-induced (300 mg/kg) plasma insulin levels, and there was no difference in glycemia among groups. In NPY-infused rats, the plasma free fatty acid levels were decreased and triglyceridemia was increased compared with controls, but these parameters were unchanged in HS014-infused rats. Hepatic triglyceride content was significantly increased by HS014 but not by NPY infusion. Levels of uncoupling protein-1 mRNA in brown adipose tissue were significantly decreased after 6 days of HS014 infusion, similar to the effect of central NPY. Because ICV HS014 induced at least as great an increase in fat mass as ICV NPY and yet had divergent hormonal and metabolic effects, we conclude that MC4 receptor antagonism does not induce obesity solely by regulation of the endogenous NPY-ergic system.  相似文献   
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We followed 12 patients who had been treated with the Ilizarov method for open proximal humeral fractures for more than 3 years. No wound infection occurred. Avascular necrosis and nonunion were each detected in 1 patient. According to Neer's criteria, the outcome was excellent or satisfactory in 8 patients.  相似文献   
148.
The dichotic rhyme task: results in split-brain patients   总被引:1,自引:0,他引:1  
Monosyllabic rhyme words were dichotically presented to normal and complete split-brain subjects. In the normal adult population, only one of the words in the dichotic condition was identified. Hence, normal performance was about 50%, with a small but significant right-ear advantage. The split-brain patients yielded the expected marked left deficit, as seen on other dichotic speech tests, and demonstrated a right-ear enhancement, producing a large interear difference. This right-ear enhancement on the dichotic rhyme task (DRT) may suggest a release from central auditory competition in the left hemisphere. The dichotic rhyme task's normative data results and sensitivity to lack of callosal transmission make it worthy of further clinical and basic research.  相似文献   
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