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111.
Approximately 75% of the PAF present in saliva is recovered on extraction of whole saliva (0.8 vol) with chloroform/methanol/water
(2∶2∶1 v/v/v). PAF levels, determined by our recently developed radioimmunoassay, in saliva extracts ranged from 0.5–21 ng/mL
with 59% between 2–6 ng/mL. These figures, for apparently healthy subjects, are higher than previously reported levels obtained
by platelet assays. The validity of our radioimmunoassay results was checked by isolating and quantitating the PAF fraction
from whole saliva. In addition, when we examined our saliva samples by platelet aggregation, low levels of PAF, comparable
with the values found in the literature, were detected. Investigations revealed the presence of a substance(s) which inhibited
PAF-induced platelet aggregation but which did not affect the radioimmunoassay. 相似文献
112.
Yen Shirley; Pagano Maria E.; Shea M. Tracie; Grilo Carlos M.; Gunderson John G.; Skodol Andrew E.; McGlashan Thomas H.; Sanislow Charles A.; Bender Donna S.; Zanarini Mary C. 《Canadian Metallurgical Quarterly》2005,73(1):99
Few studies have examined the relationship between life events, suicide attempts, and personality disorders (PDs), in spite of the strong associations between PDs and suicidal behavior, and the poor coping strategies often exhibited by these individuals. The authors examined whether participants with PDs who attempted suicide during the first 3 years of a prospective, longitudinal study were more likely to experience specific life events in the month during and preceding the suicide attempt. Of 489 participants with PDs, 61 attempted suicide during the 3-year, follow-up interval. Results indicated that negative life events, particularly those pertaining to love-marriage or crime-legal matters, were significant predictors of suicide attempts, even after controlling for baseline diagnoses of borderline PD, major depressive disorders, substance use disorders, and a history of childhood sexual abuse. Therefore, certain types of negative life events are unique risk factors for imminent suicide attempts among individuals with PDs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Rotheram-Borus Mary Jane; Weiss Robert; Alber Susan; Lester Patricia 《Canadian Metallurgical Quarterly》2005,73(2):221
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
114.
Droll Jason A.; Hayhoe Mary M.; Triesch Jochen; Sullivan Brian T. 《Canadian Metallurgical Quarterly》2005,31(6):1416
Attention and working memory limitations set strict limits on visual representations, yet researchers have little appreciation of how these limits constrain the acquisition of information in ongoing visually guided behavior. Subjects performed a brick sorting task in a virtual environment. A change was made to 1 of the features of the brick being held on about 10% of trials. Rates of change detection for feature changes were generally low and depended on the pick-up and put-down relevance of the feature to the sorting task. Subjects' sorting decision suggests that changes may be missed because of a failure to update the changed feature. The authors also explore how hand and eye behavior are coordinated for strategic acquisition and storage of visual information throughout the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Molybdenum dichalcogenides are semiconductors with layered type structure, which can act as efficient electrodes in the realization of photoelectrochemical solar cells. The main advantage of this molybdenum diselenide (MoSe2) semiconductor is the prevention of electrolyte corrosion because of the phototransitions involving non-bonding d-d orbital of the Mo atoms. Polycrystalline molybdenum diselenide thin films are prepared by pulsed electrodeposition on conducting glass and titanium substrates in galvanostatic mode from an ammoniacal solution of H2MoO4 and SeO2. The growth kinetics of the film was studied and the deposition parameters such as electrolyte bath concentration, bath temperature, time of deposition, deposition current, pH of the electrolyte and duty cycle of the current are optimized. X-ray diffraction analysis of the as deposited and annealed films showed the presence of highly textured MoSe2 films with polycrystalline nature. EDAX spectrum of the surface composition confirms the nearly stoichiometric MoSe2 nature of the film. Surface morphology studies by scanning electron microscope (SEM) shows that the films are pinhole free and of device quality nature. The optical absorption spectra show an indirect band gap value of 1.16 eV. Conductivity measurements were carried out at different temperatures and electrical constants such as activation energy, trapped energy state and barrier height were calculated. 相似文献
116.
It can be argued that the quality of software management has an effect on the degree of success or failure of a software development program. We have developed a metric for measuring the quality of software management along four dimensions: requirements management, estimation/planning management, people management, and risk management. The quality management metric (QMM) for a software development program manager is a composite score obtained using a questionnaire administered to both the program manager and a sample of his or her peers. The QMM is intended to both characterize the quality of software management and serve as a template for improving software management performance. We administered the questionnaire to measure the performance of managers responsible for large software development programs within the US Department of Defense (DOD). Informal verification and validation of the metric compared the QMM score to an overall program-success score for the entire program; this resulted in a positive correlation. 相似文献
117.
Shea M. Tracie; Stout Robert L.; Yen Shirley; Pagano Maria E.; Skodol Andrew E.; Morey Leslie C.; Gunderson John G.; McGlashan Thomas H.; Grilo Carlos M.; Sanislow Charles A.; Bender Donna S.; Zanarini Mary C. 《Canadian Metallurgical Quarterly》2004,113(4):499
In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Grilo Carlos M.; Sanislow Charles A.; Gunderson John G.; Pagano Maria E.; Yen Shirley; Zanarini Mary C.; Shea M. Tracie; Skodol Andrew E.; Stout Robert L.; Morey Leslie C.; McGlashan Thomas H. 《Canadian Metallurgical Quarterly》2004,72(5):767
The authors examined the stability of schizotypal (STPD), borderline (BPD), avoidant (AVPD) and obsessive-compulsive (OCPD) personality disorders (PDs) over 2 years of prospective multiwave follow-up. Six hundred thirty-three participants recruited at 4 collaborating sites who met criteria for 1 or more of the 4 PDs or for major depressive disorder (MOD) without PD were assessed with semistructured interviews at baseline, 6, 12, and 24 months. Lifetable survival analyses revealed that the PD groups had slower time to remission than the MDD group. Categorically, PD remission rates range from 50% (AVPD) to 61% (STPD) for dropping below diagnostic threshold on a blind 24-month reassessment but range from 23% (STPD) to 38% (OCPD) for a more stringent definition of improvement. Dimensionally, these findings suggest that PDs may be characterized by maladaptive trait constellations that are stable in their structure (individual differences) but can change in severity or expression over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
Klaczynski Paul A.; Schuneman Mary J.; Daniel David B. 《Canadian Metallurgical Quarterly》2004,40(4):559
Children and adolescents were presented with problems that contained deontic (i.e., if action p is taken, then precondition q must be met) or causal (i.e., if event p occurs, then event q will transpire) conditionals and that varied in the ease with which alternative antecedents could be activated. Results showed that inferences were linked to the availability of alternative antecedents and the generation of "disabling" conditions (claims that the conditionals were false under specific circumstances). Age-related developments were found only on problems involving indeterminate inferences. Correlations among inferences differed for children and adolescents. The findings provide stronger support for domain-general theories than for domain-specific theories of reasoning and suggest, under some conditions, age-related changes in the roles of implicit and explicit processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
120.
Welkowitz Joan; Welkowitz Lawrence A.; Struening Elmer; Hellman Fred; Guardino Mary 《Canadian Metallurgical Quarterly》2004,41(1):69
Questionnaire data from 2,033 participants in the National Anxiety Disorders Screening Day sample were used to assess the presence of panic and comorbid anxiety problems. These participants were selected from more than 15,000 attendees on the basis of never having received treatment for a psychiatric disorder and meeting screening criteria for panic disorder. With each comorbid anxiety problem (generalized anxiety disorder, posttraumatic stress disorder, social phobia, and obsessive-compulsive disorder), participants had a corresponding increase in interference in daily living as well as readiness to seek treatment. The addition of generalized anxiety or depression with panic symptoms resulted in marked increases in interference scores. Clinical treatment implications for panic disorder are discussed in terms of the effects of comorbid anxiety problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献