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BACKGROUND/AIMS: A link between abuse and irritable bowel syndrome (IBS) has been reported in outpatients but remains controversial. No population-based studies have investigated this issue. The aim of this study was to determine the prevalence of abuse and its association with symptoms in a representative community sample. METHODS: An age- and sex-stratified random sample of residents of Olmsted County, Minnesota ranging in age from 30 to 49 years was mailed a valid self-report symptom questionnaire. Abuse was assessed by standard published criteria. RESULTS: Of the 919 responders (74%), the age-adjusted prevalence of any abuse was 41% in women and 11% in men, resulting in an age- and sex-adjusted prevalence of 26%. Symptoms of IBS, dyspepsia, and frequent heartburn were reported by 14%, 23%, and 12%, respectively. There was a significant association between IBS and sexual abuse, emotional or verbal abuse, and abuse in childhood and adulthood. Similarly, dyspepsia and heartburn were both significantly associated with abuse. In the population, 31% had visited a physician for gastrointestinal symptoms; the odds of visiting a physician were highest in those reporting abuse in adulthood and childhood. CONCLUSIONS: Self-reported abuse is common in middle-aged subjects; those who report abuse are more likely to have symptoms consistent with IBS, dyspepsia, or heartburn and to visit a physician for bowel symptoms.  相似文献   
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The phase diagram of the CaCl2-CaF2-MgCl2-MgF2 reciprocal ternary system was calculated thermodynamically from available data on the common-ion binary subsystems and from available data on the CaCl2-MgF2 join. This join is very nearly quasibinary and divides the system into two quasiternary systems: the CaCl2-MgF2-CaF2 system with a ternary eutectic calculated at 724 +-5 °C and the CaC2-MgF2-MgCl2 system with a ternary eutectic calculated at 561 +-5 °C.  相似文献   
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Previous research has shown that sexual minority (i.e., nonheterosexual) individuals report increased problematic substance use involvement, compared with their sexual majority counterparts. We hypothesize that feelings of an unstable sense of self (i.e., identity disturbance) may potentially drive problematic substance use. The purpose of the current study is to examine identity disturbance among sexual minorities as a potential explanatory mechanism of increased sexual minority lifetime rates of substance dependence. Measures of identity disturbance and three indicators of sexual orientation from lifetime female (n = 16,629) and male (n = 13,553) alcohol/illicit drug users in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were examined. Findings generally showed that the increased prevalence of alcohol dependence, illicit drug dependence, and combined alcohol/illicit drug dependence as well as a younger age of alcohol use initiation among sexual minority women was associated with elevated levels of identity disturbance. The results were consistent with a mediational role for identity disturbance in explaining the association between sexual minority status and substance dependence and were generally replicated among male sexual minority respondents. The current research suggests that identity disturbance, a predictor of substance use, may contribute to heightened risk for substance dependence among certain subgroups of sexual minority individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Social reforms in American education are setting the stage for a paradigm shift in our nation's schools. The convergence of education and health care reform and the movement in the human services arena toward service integration models provide an unprecedented opportunity to redefine psychological services related to schools for the next century. Whereas school psychological services historically have been linked to changes in special education legislation, social reforms in education and health care that emphasize educational achievement and whole-child development offer promise for expanding and enhancing the roles of psychologists whose practices relate to schools and children. This article explores the foundations for change and highlights critical areas in which psychological practice in the schools may develop in the 1990s and beyond. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In order to increase its potential as a food ingredient, an oil fraction derived from a commercial edible beef tallow was substituted for soybean oil in a formulation designed to yield a spray-dried free-flowing powder readily reconstitutable with water to yield a nutritious beverage. If desired, the beverage powder could be fortified with a vitamin-mineral premix containing iron. After 6 months of storage at 37 C, no significant difference in flavor score was observed between samples containing the beef tallow oil fraction and control samples containing soybean oil. There was also no significant difference in flavor scores received by samples containing the beef tallow oil fraction fortified with vitamins and minerals and fortified control samples. However, peroxide values were eight times greater in the unfortified control samples. The beef tallow oil fraction warrants further study as a food ingredient in engineered food systems where enhanced oxidative stability is desirable.  相似文献   
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Dredged sediment from Milwaukee Harbor showed two primary classes of particles in the <2 mm size range: a lighter-density coal- and wood-derived fraction with 62% of total PAHs and a heavier-density sand, silt, and clay fraction containing the remaining 38% of the PAHs. Room-temperature PAH desorption kinetic studies on separated sediment fractions revealed slow desorption rates for the coal-derived particles and fast desorption rates for the clay/silt particles. The effect of temperature on PAH release was measured by thermal program desorption mass spectrometry to investigate the desorption activation energies for PAHs on the different sediment particles. Three activated diffusion-based models and an activated first-order rate model were used to describe the thermal desorption of PAHs for four molecular weight classes. PAH binding with the coal-derived particles was associated with high activation energies, typically in the range of 115-139 kJ/mol. PAHs bound to the clay/silt material had much lower activation energy, i.e., in the range of 37-41 kJ/ mol for molecular weight 202. Among the desorption models tested, a spherical diffusion model with PAHs located like a rind on the outer 1-3 microm region best described the PAH thermal desorption response for coal-derived particles. This internal PAH distribution pattern on coalderived particles is based on prior direct measurement of PAH locations at the subparticle scale. These studies reveal that heterogeneous particle types in sediment exhibit much different amounts and binding of PAHs. PAHs associated with coal-derived particles aged over several decades in the field appear to be far from reaching an equilibrium sorption state due to the extremely slow diffusivities through the polymer-like coal matrix. These results provide an improved mechanistic perspective for the understanding of PAH mobility and bioavailability in sediments.  相似文献   
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The present study develops an interfacial area transport equation applicable to an air-water horizontal bubbly flow, along which two types of horizontal elbows are installed as flow restrictions. Two sets of experiments are performed in a round glass tube of 50.3 mm inner diameter. Along the test section, a 90-degree elbow is installed at L/D = 206.6 from the two-phase mixture inlet and then a 45-degree elbow is installed at L/D = 353.5. In total, 15 different flow conditions in the bubbly flow regime for each of the two flow restriction experiments are studied. Detailed local two-phase flow parameters are acquired by a double-sensor conductivity probe at four different axial locations in the 90-degree experiment and three different axial locations in the 45-degree experiment. The effect of the elbows is found to be evident in the distribution of local parameters as well as in the development of interfacial structures. It is clear that the elbows make an effect on the bubble interactions resulting in significant changes to both the void fraction and interfacial area concentration. In the present analysis, the interfacial area transport equation is developed in one-dimensional form via area averaging. In the averaging process, characteristic non-uniform distributions of the flow parameters in horizontal two-phase flow are treated mathematically through a distribution parameter. The mechanistic models for the major bubble interaction phenomena developed in vertical flow analysis are employed in the present study. Furthermore, the change in pressure due to the minor loss of an elbow is taken into consideration by using a newly developed correlation analogous to Lockhart and Martinelli's. In total, 105 area-averaged data points are employed to benchmark the present model. The present model predicts the data relatively well with an average percent difference of approximately ±20%.  相似文献   
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Catalytic antibodies are introduced as an important new class of biomolecules for molecular recognition in biosensors in which the binding sites are continually regenerated by the catalytic reaction of the substrate. Consequently, molecular recognition by catalytic antibodies can yield reversible immunoblosensors. In this example, a prototype potentiometric biosensor is described in which a micro-pH electrode is modified with a catalytic antibody that catalyzes the hydrolysis of phenyl acetate, producing hydrogen ions that can be monitored by the electrode. The reversible response is linear with the log of substrate concentration over a range of 20-500 microM with a detection limit of 5 microM under the conditions of this study. Alternative applications of catalytic antibodies in other biosensor configurations are discussed.  相似文献   
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