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991.
992.
At rest position and varied clenching levels at intercuspal position, autoregressive (AR) models of myoelectrical activities of both masseter and anterior temporal muscles of 11 healthy subjects with intact natural dentitions were established. The relationship between the AR model coefficients of surface EMGs and their potentials was analyzed by multiple linear regression. It was found that the fourth order coefficient of AR had the greatest effect on the EMG potential levels and their relationship was positive in all recorded muscles. The results indicate the AR coefficients may become a characteristic parameter to describe myoelectrical activity of jaw closing muscles.  相似文献   
993.
994.
Objective: To explore the relationship between employment status and community access, perceived community discrimination, social support from significant others, depressive symptoms, and gender-related variables for 83 men living with spinal cord injury. Study Design: Correlational research. Setting: Internet-based investigation employing spinal cord injury listservs. Main Outcome Measure: Participant employment status. Results: A forced-entry hierarchical logistic regression indicated that means of injury, community access and perceived community discrimination, social support from significant others, depressive symptoms, and men’s adherence to masculine norms for primacy of work, self-reliance, and emotional control significantly predicted employment status. Conclusions: Psychosocial variables such as community access, perceived discrimination, social support from significant others, depressive symptoms, and gender identity represent important and understudied predictors of employment status among men living with spinal cord injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
996.
The crystal structure of human immunodeficiency virus (HIV) type 2 protease has been determined in complexes with peptidic inhibitors Noa-His-Cha psi [CH(OH)CH(OH)]Val-Ile-Amp (U75875) and Qnc-Asn-Cha psi [CH(OH)CH2]Val-Npt(U92163) (where Noa is naphthyloxyacetyl, Cha is cyclohexylalanine, Amp is 2-aminomethylpyridine, Qnc is quinoline-2-carbonyl, and Npt is neopentylamine), which have dihydroxyethylene and hydroxyethylene moieties, respectively, in place of the normal scissile bond of the natural ligand. The complexes crystallize in space group P2(1)2(1)2(1), with one dimer-inhibitor complex per asymmetric unit and average cell dimensions of a = 33.28 A, b = 45.35 A, c = 135.84 A. Data were collected to approximately 2.5-A resolution. The model structures were refined with resulting R-factors of around 0.19. As expected, the HIV-2 protease structure is approximately C2-symmetric with a gross structure very similar to that of the HIV-1 enzyme. The inhibitors bind in an extended conformation positioned lengthwise in the binding cleft in a manner similar to that found in the HIV-1 protease-inhibitor complexes previously reported. The substitution of the bulkier Ile82 side chain in the HIV-2 protease may help explain the better ability of HIV-2 protease to bind and hydrolyze ligands with small P1 and P1' side groups. It appears that differences in specificity between the proteases of HIV-1 and HIV-2 are not merely a result of simple side chain substitutions, but may be complicated by differences in main chain flexibility as well.  相似文献   
997.
The elevation of intracellular levels of cyclic AMP by forskolin stimulation of adenylate cyclase regulates early and late phase neutrophil responses differentially. Early phase neutrophil responses as measured by shape change in response to chemotactic factors, transmigration across a polycarbonate membrane and priming were unaffected by forskolin-induced elevation of intracellular cAMP. Late phase neutrophil responses such as release of superoxide anions, activation of phospholipase A2 and platelet activating factor (PAF) synthesis were inhibited by increasing intracellular cAMP through the addition of 10 microM forskolin for 10 min prior to stimulation. N-Formyl-methionyl-leucyl-phenylalanine-stimulated arachidonic acid release fell from 9.3% (untreated cells) to 4.6% in forskolin-treated cells. PAF generation was also inhibited from 430 pg/10(6) cells in untreated cells to background levels in forskolin-treated cells (110 pg/10(6) cells). Also, the reduction of cytochrome c by superoxide anions fell from 4.2 nmol/10(6) cells in the absence of forskolin to 2.0 nmol/10(6) cells following forskolin treatment. These results indicate that in neutrophils the elevation of cAMP acts differentially on cellular responses, not affecting early activation events, but markedly inhibiting late events such as the release of inflammatory mediators.  相似文献   
998.
Therapists and clients reported on their own and their perceptions of each other's covert processes in long-term therapy. Therapists had a match rate of .45 for client reactions, with therapists rating match on therapeutic work reactions as helpful. Although 65% of clients left somethimg unsaid (primarily because of avoidance), only 27% of therapists were able to match what clients left unsaid. Of the clients, 46% had secrets (often sexual), primarily because of shame or insecurity. Clients had a match rate of .50 for therapist intentions, with therapists rating match on exploratory and restructuring intentions as helpful and both clients and therapists rating match on assessment intentions as not helpful. Thus, awareness of the other's covert processes had an effect on therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
Multicultural experience is considered to be beneficial, but it remains a difficult construct to measure. We tested the validity of a new assessment tool, the Multicultural Experiences Questionnaire (MEQ), using an undergraduate sample (N = 164), and examined the relation of multicultural experience to moral judgment, closed-mindedness, growth, and fixed mindsets. We expected that greater multicultural experience would be related to lower levels of closed-mindedness and higher levels of moral judgment and growth mindsets. Higher MEQ scores were correlated with decreased closed-mindedness and higher moral judgment scores. In regression analyses, controlling for age and sex, higher MEQ scores positively predicted participant scores on postconventional moral judgment and growth mindsets, but negatively predicted use of less developed moral judgment and fixed mindsets. Overall, these results support the validity of the MEQ and suggest that multicultural experiences are positively linked to measures of moral judgment and growth mindsets. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and two-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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