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81.
New mathematical models from physiologically interpreted parameters capable of evaluating glucose metabolism within the liver and/or the whole body were developed. The group of pigs in a fasting state and the group of pigs with euglycemic supraphysiological hyperinsulinemia were scanned by positron emission tomography after a single dose of [(18)F]FDG tracer. Simultaneously frequent sampling of the dynamic data of [(18)F]FDG plasma concentration in artery, portal vein and hepatic vein was obtained. A system approach to the liver and/or the whole-body system by the tools of linear dynamic sysztem theory was used. Three kinds of structural models, single input and single output or multiple outputs and multiple inputs and single output, were identified. Differences between the group of fasting pigs and the group of pigs in euglycemic supraphysiological hyperinsulinemia were identified by estimated parameters of the structural models. The suitability of the structural mathematical models for the estimation of physiologically interpreted parameters from PET was validated.  相似文献   
82.
We have identified and cloned the cDNAs encoding two odorant-binding proteins (OBPs) from the American palm weevil (APW) Rhynchophorus palmarum (Coleoptera, Curculionidae). Degenerate primers were designed from the N-terminal sequences and were used in polymerase chain reaction (PCR) in order to obtain full-length sequences in both males and females. In both sexes, two different cDNAs were obtained, encoding 123 and 115 amino acid-deduced sequences. Each sequence showed few amino acid differences between the sexes. The proteins were named RpalOBP2 and RpalOBP4 for male, RpalOBP2' and RpalOBP4' for female, with the types 2 and 4 presenting only 34% identities. These proteins shared high identity with previously described coleopteran OBPs. In native gels, RpalOBP2 clearly separated into two bands and RpalOBP4 into three bands, suggesting the presence of several conformational isomers. Thus, OBP diversity in this species may rely on both the presence of OBPs from different classes and the occurrence of isoforms for each OBP.  相似文献   
83.
It was possible to fractionate soy protein into two soy protein isolate fractions (>90% protein) enriched in either glycinin or β-conglycinin by using a new simplified procedure (referred to as the Deak procedure) employing CaCl2 and NaHSO3. The Deak procedure produced fractions with higher yields of solids, protein, and isoflavones, and similar protein purities as well as improved functional properties compared to fractions recovered by established, more complex soy protein fractionation procedures. The Deak glycinin-rich fraction comprised 15.5% of the solids, 24.4% of the protein, and 20.5% of the isoflavones in the starting soy flour, whereas the glycinin-rich fraction of the established procedure (Wu procedure) comprised only 11.6% of the solids, 22.3% of the protein, and 9.6% of the isoflavones. The Deak β-conglycinin-rich fraction comprised 23.1% of the solids, 37.1% of the protein, and 37.5% of the isoflavones in the starting soy flour, whereas the Wu β-conglycinin-rich fraction comprised only 11.5% of the solids, 18.5% of the protein, and 3.3% of the isoflavones. Protein purities were >80% for both fractions when using both procedures. The Wu procedure produced protein fractions with slightly higher solubilities and similar surface hydrophobicities; whereas, the fractions produced by the Deak procedure had superior emulsification and foaming properties and similar dynamic viscosity behaviors.  相似文献   
84.
Laboratory experiments were conducted to investigate the abiotic interactions of soybean oil (SoyOil) and chlorinated ethene (CE) nonaqueous phase liquids (NAPLs). The mixed NAPL density and interfacial tension behaved ideally, as predicted by the volume ratio. The mixed NAPL viscosity increased exponentially from that of the pure CE to that of pure SoyOil as the volume fraction increased. The measured contact angle was highly variable and was unpredictable as a function of the volume composition of the mixed NAPL. The physical property effects indicate that the mobilization of residual CE NAPLs because of SoyOil injection is unlikely. Equilibrium dissolution of CEs from the NAPL mixtures behaved linearly as a function of the mole fraction. Dissolved SoyOil in simulated groundwater enhanced the dissolution of trichloroethene (TCE) during flow tests, increasing the effluent TCE concentration from 141?to?202?mg/L. The ready intermingling of the CE dense nonaqueous phase liquids (DNAPLs) and SoyOil indicate that such interactions may be significant at sites where vegetable oil is injected into DNAPL source areas to enhance in situ anaerobic bioremediation.  相似文献   
85.
The impact of HIV-related parental death on 414 adolescents was examined over a period of 6 years. The adjustment of bereaved adolescents was compared over 4 time periods relative to parental death and was also compared with the adjustment of nonbereaved adolescents. Bereaved adolescents had significantly more emotional distress, negative life events, and contact with the criminal justice system than nonbereaved youths; these behaviors did not remain significantly higher after parental death. Depressive symptoms and passive problem solving increased soon after parental death, as compared with nonbereaved adolescents. One year subsequent to parental death, depression and passive problem solving were similar to the levels of nonbereaved peers. Only sexual risk behaviors increased following parental death. These results suggest the importance of early family intervention soon after parental HIV diagnosis, prior to parental death, and sustained over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
Results from studies using a behavioral high-risk design and approximations to it generally have corroborated the cognitive vulnerability hypothesis of depression, whereas results from remitted depression studies typically have not. Suspecting that design features of previously conducted remitted designs likely precluded them from detecting maladaptive cognitive patterns, the authors conducted a study featuring the remitted design that has been successful in studies of a biological vulnerability for depression. Participants' current depressive symptoms, negative cognitive styles (hopelessness theory), dysfunctional attitudes (Beck's theory), and lifetime prevalence of clinically significant depression were assessed. Participants who had remitted from an episode of clinically significant depression had more negative cognitive styles, but not greater levels of dysfunctional attitudes, than did never depressed individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
The authors tested the acculturation gap-distress hypothesis by examining whether parent-adolescent acculturation gaps were associated with greater conflict and youth conduct problems among 260 high-risk Mexican American families. The authors operationalized acculturation gaps in 2 ways: parent-youth mismatches in acculturation style, and parent-youth discrepancies in acculturation toward both mainstream and heritage cultures. Acculturation gaps were common, but results of hierarchical regression analyses indicated that parent-youth discrepancies in acculturation toward mainstream and heritage cultures were not related to increased conflict or youth conduct problems. Conduct problems were no higher in families in which the adolescent was more aligned with mainstream culture than the parent. Unexpectedly, the authors found more youth conduct problems in families in which the youth was more aligned with traditional culture than the parent. The results call into question the assumption that the more rapid acculturation of adolescents to American culture inevitably leads to distress in minority families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
Depression in adolescent girls may result in negative consequences in young adulthood. The Center for Epidemiologic Studies Depression Scale (CES-D) was administered to 1,727 Black and White girls ages 16 to 18 years who participated in the National Heart, Lung, and Blood Institute's Growth and Health Study. Three years later, women in the depressed groups were more likely to be current smokers, had attained a lower level of education, and reported lower self-worth relative to the nondepressed group. Body dissatisfaction, eating concerns, and loneliness were greater in the depressed groups. Relative to Black women, White women who were moderately depressed during adolescence reported more health care services utilization in young adulthood. Prevention efforts for depressed adolescents should be broadly focused to improve young adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
In a cross-sectional sample of 428 employees, the job demand-control-support and effort-reward imbalance job stress models were amalgamated and expanded to include modifiable risk factors and noncontrollable genetic factors related to cardiovascular disease (CVD) risk. With structural equation modeling, the constructs of lack of job resilience, lack of personal resilience, and job demand were used to examine how employer and employee factors related to psychosomatic strain and risk indicators of CVD. Negative perception of job demand predicted perception of lack of job resilience but not lack of personal resilience. Lack of job and personal resilience predicted strain. Women reported greater strain than men. CVD risk was predicted by strain, age, sex, and family history. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
Working memory mediates the short-term maintenance of information. Virtually all empirical research on working memory involves investigations of working memory for verbal and visual information. Whereas aging is typically associated with a deficit in working memory for these types of information, recent findings suggestive of relatively well-preserved long-term memory for emotional information in older adults raise questions about working memory for emotional material. This study examined age differences in working memory for emotional versus visual information. Findings demonstrate that, despite an age-related deficit for the latter, working memory for emotion was unimpaired. Further, older adults exhibited superior performance on positive relative to negative emotion trials, whereas their younger counterparts exhibited the opposite pattern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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