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1.
The human obesity gene map: the 1997 update   总被引:1,自引:0,他引:1  
An update of the human obesity gene map incorporating published results up to October 1997 is presented. Evidence from Mendelian disorders exhibiting obesity as a clinical feature; single-gene mutation rodent models; quantitative trait loci uncovered in human genome-wide scans and in crossbreeding experiments with mouse, rat, and pig models; association and case-control studies with candidate genes; and linkage studies with genes and other markers is reviewed. All chromosomal locations of the animal loci are converted into human genome locations based on syntenic relationships between the genomes. A complete listing of all of these loci reveals that all but chromosome Y of the 24 human chromosomes are represented. Some chromosomes show at least three putative loci related to obesity on both arms (1, 2, 6, 8, 11, and 20) and several on one chromosome arm only (3p, 4q, 5q, 7q, 12q, 13q, 15q, 15p, 22q, and Xq). Studies reporting negative association and linkage results are also listed, with the exception of the unlinked markers from genome-wide scans.  相似文献   
2.
Responds to the points made by R. Cropanzano and K. James (see record 1991-00462-001) concerning the article by R. D. Arvey et al (1989). The authors acknowledge that the Arvey et al study is based on a single design, makes use of a small and special sample, and, as such, is vulnerable to threats of internal and external validity. Nevertheless, after providing a more comprehensive conceptual and empirical context for the study, and after reviewing a number of the issues raised by Cropanzano and James, the authors conclude that it is not premature to accept the idea that work attitudes are partially genetically influenced. Indeed, the authors use behavioral genetic theory, together with data gathered in the Arvey et al study, to make specific point predictions regarding the outcomes of an array of studies that easily can be undertaken. Finally, the authors acknowledge that the comments and issues raised by Cropanzano and James, along with the interchange, can offer directions for future research in this important area. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
We administered the Multidimensional Personality Questionnaire (MPQ) to 217 monozygotic and 114 dizygotic reared-together adult twin pairs and 44 monozygotic reared-apart adult twin pairs. A four-parameter biometric model (incorporating genetic, additive versus nonadditive, shared family-environment, and unshared environment components) and five reduced models were fitted through maximum-likelihood techniques to data obtained with the 11 primary MPQ scales and its 3 higher order scales. Solely environmental models did not fit any of the scales. Although the other reduced models, including the simple additive model, did fit many of the scales, only the full model provided a satisfactory fit for all scales. Heritabilities estimated by the full model ranged from .39 to .58. Consistent with previous reports, but contrary to widely held beliefs, the overall contribution of a common family-environment component was small and negligible for all but 2 of the 14 personality measures. Evidence of significant nonadditive genetic effects, possibly emergenic (epistatic) in nature, was obtained for 3 of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Although progesterone and estrogens are essential to maintain human pregnancy after implantation, the localization of their specific receptors in different uterine cell types during pregnancy has not been investigated. We studied uteri (n = 40) obtained during the first 3 months of pregnancy (n = 21) and in late pregnancy (n = 9) as well as from women 5-14 weeks pregnant (n = 10) who had received the antiprogestagen RU 38486 (Roussel-UCLAF) to induce cervical dilation. Frozen tissues were processed for indirect immunocytochemical staining with specific monoclonal antibodies against estrogen receptors (ER; Abbott Laboratories) and progesterone receptors (PR; Li 417). Specific staining for steroid receptors was only detected in the nucleus. In the endometrium, PR staining remained fairly constant throughout pregnancy, whereas ER staining was initially weak and then undetectable. PR was widely expressed in stromal cells and in spiral arterial wall cells, whereas ER was expressed in scattered stromal cells and arterial cells. Both PR and ER were absent from glandular epithelium, contrasting with the secretory activity during the first trimester. Spiral arteries of the endometrium and myometrial smooth muscle cells showed intense PR and moderate ER staining in early pregnancy. The progesterone antagonist RU 38486 (mifepristone), given in early pregnancy at a dose of 200 mg, caused a marked increase in ER staining and a smaller increase in PR staining in stromal cells, whereas the glandular epithelium remained negative for both ER and PR (except for one and two specimens, respectively). We conclude the following. 1) Stromal cells retain PR despite the high progesterone levels during pregnancy, in keeping with the role of progesterone in stromal decidualization. The absence of PR from the secretory glandular epithelium suggests a paracrine link between decidualized stromal cells and epithelial cells. 2) Significant PR down-regulation by progesterone during pregnancy occurs only in epithelial cells of the endometrium. 3) In contrast, the absence or low level of ER staining in the various cell types of the endometrium during gestation concurs with the known effect (down-regulation) of steroid hormones on ER mRNA or protein levels. The increase in ER in human decidua after RU 38486 treatment indicates that the main cause of the low ER levels is progesterone secretion. 4) The intense PR staining in smooth muscle cells of spiral arteries during early pregnancy suggests that progesterone is essential for modulating blood flow during pregnancy.  相似文献   
6.
In this work, nanopowders of perovskite cathode materials (La0.8Sr0.2MnO3−δ, La0.8Sr0.2FeO3−δ, and La0.8Sr0.2CoO3−δ), for use in solid oxide fuel cells (SOFC), were successfully synthesized, using induction plasma techniques. Their compositions, structures, morphology, particle size distributions, and BET specific surface areas were determined for comparison with their counterparts prepared by the Pechini method and by the glycine-nitrate combustion (GNC) technique. The particle sizes of the plasma-synthesized powders are mostly around 63 nm. These plasma-synthesized powders are generally globular, their BET specific surface areas being about 26 m2g−1, approximately twice those of powders prepared by the GNC and Pechini methods. These plasma-synthesized powders are readily reproducible and are not agglomerated. Their individual particle sizes and distributions are very independent of their composition.  相似文献   
7.
Shimming systems are required to provide sufficient field homogeneity for high resolution nuclear magnetic resonance (NMR). In certain specialized applications, such as rotating-field NMR and mobile ex situ NMR, permanent magnet-based shimming systems can provide considerable advantages. We present a simple two-dimensional shimming method based on harmonic corrector rings which can provide arbitrary multipole order shimming corrections. Results demonstrate, for example, that quadrupolar order shimming improves the linewidth by up to an order of magnitude. An additional order of magnitude reduction is in principle achievable by utilizing this shimming method for z-gradient correction and higher order xy gradients.  相似文献   
8.
Life cycle assessment (LCA) allows evaluating the potential environmental impacts of a product or a service in relation to its function and over its life cycle. In past LCAs applied to wastewater treatment plants (WWTPs), the system function definition has received little attention despite its great importance. This has led to some limitations in LCA results interpretation. A new methodology to perform LCA on WWTPs is proposed to avoid those limitations. It is based on net environmental benefit (NEB) evaluation and requires assessing the potential impact of releasing wastewater without and with treatment besides assessing the impact of the WWTP's life cycle. The NEB allows showing the environmental trade-offs between avoided impact due to wastewater treatment and induced impact by the WWTP's life cycle. NEB is compared with a standard LCA through the case study of a small municipal WWTP consisting of facultative aerated lagoons. The NEB and standard LCA show similar results for impact categories solely related to the WWTP's life cycle but differ in categories where wastewater treatment environmental benefit is accounted for as NEB considers influent wastewater quality whereas standard LCA does not.  相似文献   
9.
Abstract:  A study of pressurised cylinders having attached pads was made. The possibility of a fatigue crack developing along one side of the pad was noted. For both defect-free components and components having axial crack-like defects, finite element and limited experimental studies of the local and global deformations were made and results were found to be in close agreement. Both welded and integrally machined pads were studied. It was observed that for defect-free components, the method of pad attachment has little effect on the burst pressure. The presence of a pad was found to increase the burst pressure of cracked components by a small but significant margin. A finite element-based parametric study of pipes with part-penetrating defects and a range of pad geometries has demonstrated that pad size has little influence on the limit load for any of the cracked cases considered. However, pipes with penetrating defects were strengthened by the presence of pads, particularly for thin-walled sections.  相似文献   
10.
Penile plethysmography (PPG) is the gold standard for the assessment of sexual interests, especially among sex offenders of children. Nonetheless, this method faces some ethical limitations inherent to the nature of its stimuli and could benefit from the improvement of its ecological validity. The use of computer-generated characters (CGC) in virtual immersion for PPG assessment might help address these issues. A new application developed to design made-to-measure anatomically correct virtual characters compatible with the Tanner developmental stages is presented. The main purpose of this study was to determine how the virtual reality (VR) modality compares to the standard auditory modality on their capacity to generate sexual arousal profiles and deviance differentials indicative of sexual interests. The erectile responses of 22 sex offenders of children and 42 non-deviant adult males were recorded. While both stimulus modalities generated significantly different genital arousal profiles for sex offenders of children and non-deviant males, deviance differentials calculated from the VR modality allowed for significantly higher classification accuracy. Performing receiver operating characteristic analyses further assessed discriminant potential. Auditory modality yielded an area under the curve (AUC) of 0.79 (SE = 0.059) while CGC in VR yielded an AUC of 0.90 (SE = 0.052). Overall, results suggest that the VR modality allows significantly better group classification accuracy and discriminant validity than audio stimuli, which provide empirical support for the use of this new method for PPG assessment. Additionally, the potential use of VR in interventions pertaining to self-regulation of sexual offending is addressed in conclusion.  相似文献   
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