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Twin studies suggest that propensity to smoke and ability to quit smoking are influenced by genetic factors. As a means of investigating the risk of smoking associated with genetic polymorphisms in the dopamine transporter (SLC6A3) and the D? dopamine receptor (DRD2) genes, a case-control study of 289 smokers and 233 nonsmoking controls and a case series analysis of smokers were conducted. A significant effect for SLC6A3 and a significant gene-gene interaction were found in a logistic regression model, indicating that individuals with SLC6A3-9 genotypes were significantly less likely to be smokers, especially if they also had DRD2-A2 genotypes. Smokers with SLC6A3-9 genotypes were also significantly less likely to have started smoking before 16 years of age and had prior smoking histories indicating a longer period of prior smoking cessation. This study provides preliminary evidence that the SLC6A3 gene may influence smoking initiation and nicotine dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Recently, we reported a case of an infant with neonatal severe under-mineralizing skeletal dysplasia caused by mutations within both alleles of the TRPV6 gene. One mutation results in an in frame stop codon (R510stop) that leads to a truncated, nonfunctional TRPV6 channel, and the second in a point mutation (G660R) that, surprisingly, does not affect the Ca2+ permeability of TRPV6. We mimicked the subunit composition of the unaffected heterozygous parent and child by coexpressing the TRPV6 G660R and R510stop mutants and combinations with wild type TRPV6. We show that both the G660R and R510stop mutant subunits are expressed and result in decreased calcium uptake, which is the result of the reduced abundancy of functional TRPV6 channels within the plasma membrane. We compared the proteomic profiles of a healthy placenta with that of the diseased infant and detected, exclusively in the latter two proteases, HTRA1 and cathepsin G. Our results implicate that the combination of the two mutant TRPV6 subunits, which are expressed in the placenta of the diseased child, is responsible for the decreased calcium uptake, which could explain the skeletal dysplasia. In addition, placental calcium deficiency also appears to be associated with an increase in the expression of proteases.  相似文献   
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Male infertility is a common health problem that can be influenced by a host of lifestyle risk factors such as environment, nutrition, smoking, stress, and endocrine disruptors. These effects have been largely demonstrated on sperm parameters (e.g., motility, numeration, vitality, DNA integrity). In addition, several studies showed the deregulation of sperm proteins in relation to some of these factors. This review inventories the literature related to the identification of sperm proteins showing abundance variations in response to the four risk factors for male infertility that are the most investigated in this context: obesity, diabetes, tobacco smoking, and exposure to bisphenol-A (BPA). First, we provide an overview of the techniques used to identify deregulated proteins. Then, we summarise the main results obtained in the different studies and provide a compiled list of deregulated proteins in relation to each risk factor. Gene ontology analysis of these deregulated proteins shows that oxidative stress and immune and inflammatory responses are common mechanisms involved in sperm alterations encountered in relation to the risk factors.  相似文献   
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Objective: Cognitive models of panic disorder suggest that change in catastrophic misinterpretations of bodily sensations will predict symptom reduction. To examine change processes, we used a repeated measures design to evaluate whether the trajectory of change in misinterpretations over the course of 12-week cognitive behavior therapy is related to the trajectory of change in a variety of panic-relevant outcomes. Method: Participants had a primary diagnosis of panic disorder (N = 43; 70% female; mean age = 40.14 years). Race or ethnicity was reported as 91% Caucasian, 5% African American, 2.3% biracial, and 2.3% “other.” Change in catastrophic misinterpretations (assessed with the Brief Body Sensations Interpretation Questionnaire; Clark et al., 1997) was used to predict a variety of treatment outcomes, including overall panic symptom severity (assessed with the Panic Disorder Severity Scale [PDSS]; Shear et al., 1997), panic attack frequency (assessed with the relevant PDSS item), panic-related distress/apprehension (assessed by a latent factor, including peak anxiety in response to a panic-relevant stressor—a straw breathing task), and avoidance (assessed by a latent factor, which included the Fear Questionnaire–Agoraphobic Avoidance subscale; Marks & Mathews, 1979). Results: Bivariate latent difference score modeling indicated that, as expected, change in catastrophic misinterpretations predicted subsequent reductions in overall symptom severity, panic attack frequency, distress/apprehension, and avoidance behavior. However, change in the various symptom domains was not typically a significant predictor of later interpretation change (except for the distress/apprehension factor). Conclusions: These results provide considerable support for the cognitive model of panic and speak to the temporal sequence of change processes during therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
水路和水面     
罗德诺霍夫农舍位于奥地利慕维特尔区的偏僻空地上,一对已婚夫妇周末常来此度假。翻修建筑的时候,为更好利用花园,房主和建筑师把原来倾斜的场地修成了台地。场地北边的清水混凝土墙围成一个狭窄的长形水池。房子后方天井的窗户和坐凳是用裸露的混凝土墙建成的。容易引人注意,水生植物在墙上投射下形状不同的影子。水池还具有过滤的功能。在另一头,水流淌过沙砾池底,然后进入地下泳池。一个太阳能水泵把水抽回到过滤池。泳池的四周种着黑刺李树,一棵老樱桃树为池边的观景木台提供了遮荫功能。可循  相似文献   
47.
As part of the ecological risk assessment associated with radionuclides in freshwater ecosystems, toxicity of waterborne uranium was recently investigated in the microcrustacean Daphnia magna over a three-generation exposure (F0, F1, and F2). Toxic effects on daphnid life history and physiology, increasing over generations, were demonstrated at the organism level under controlled laboratory conditions. These effects were modeled using an approach based on the dynamic energy budget (DEB). For each of the three successive generations, DEBtox (dynamic energy budget applied to toxicity data) models were fitted to experimental data. Lethal and sublethal DEBtox outcomes and their uncertainty were projected to the population level using population matrix techniques. To do so, we compared two modeling approaches in which experimental results from F0, F1, and F2 generations were either considered separately (F0-, F1-, and F2-based simulations) or together in the actual succession of F0, F1, and F2 generations (multi-F-based simulation). The first approach showed that considering results from F0 only (equivalent to a standard toxicity test) would lead to a severe underestimation of uranium toxicity at the population level. Results from the second approach showed that combining effects in successive generations cannot generally be simplified to the worst case among F0-, F1-, and F2-based population dynamics.  相似文献   
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Counterfactual thoughts typically take the form of implied or explicit if–then statements. We propose that the multiplicative combination of “if likelihood” (the degree to which the antecedent condition of the counterfactual is perceived to be likely) and “then likelihood” (the perceived conditional likelihood of the outcome of the counterfactual, given the antecedent condition) determine the strength and impact of counterfactuals. This construct, termed counterfactual potency, is a reliable predictor of the degree of influence of counterfactual thinking upon judgments of regret, causation, and responsibility. Through 4 studies, we demonstrate the predictive power of this construct in a variety of contexts and show that it plays a causal role in determining the strength of the effects of counterfactual thought. Implications of counterfactual potency as a central factor of counterfactual influence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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