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41.
Investigated the effects of alcohol on self-regulation using delay of gratification for viewing time for an erotic film as the primary dependent measure. Other measures included reflection–impulsivity, locus of control, sexual-guilt scores, and continuous recording of Ss' penile tumescence. Using a balanced placebo design with 50 undergraduate men, Ss were led to believe that they had consumed an alcoholic or a nonalcoholic beverage, and half of each of these 2 groups received either alcohol or tonic water. In addition, the effects of 3 doses of alcohol (placebo, low dose, high dose) were investigated. Instructional set, regardless of drink content, resulted in longer delay times and increased thoughts with sexual content. Although there was no significant relation between increasing dose of alcohol and delay time, there was an interaction between scores on Rotter's Internal–External Locus of Control Scale and alcohol dose. Externalizers showed an inverse linear relation between increasing dose of alcohol and delay time. Internalizers showed the opposite trend. Results support other research showing that expectations about drinking can be more potent predictors of behavior than the pharmacological impact of alcohol. Implications for the self-regulation of sexual behavior under the influence of alcohol are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A biochemical analysis of glycoprotein C (gC of herpes simplex virus was undertaken to further characterize the structure of the glycoprotein and to determine its disulfide bond arrangement. We used three recombinant forms of gC, gC1(457t), gC1(delta33-123t), and gC2(426t), each truncated prior to the transmembrane region. The proteins were expressed and secreted by using a baculovirus expression system and have been shown to bind to monoclonal antibodies which recognize discontinuous epitopes and to complement component C3b in a dose-dependent manner. We confirmed the N-terminal residues of each mature protein by Edman degradation and confirmed the internal deletion in gC1(delta33-123t). The molecular weight and extent of glycosylation of gC1 (457t), gC1(delta33-123t), and gC2(426t) were determined by treating each protein with endoglycosidases and then subjecting it to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometric analysis. The data indicate that eight to nine of the predicted N-linked oligosaccharide sites on gC1(457t) are occupied by glycans of approximately 1,000 Da. In addition, O-linked oligosaccharides are present on gC1(457t), primarily localized to the N-terminal region (amino acids [aa] 33 to 123) of the protein. gC2(426t) contains N-linked oligosaccharides, but no O-linked oligosaccharides were detected. To determine the disulfide bond arrangement of the eight cysteines of gC1(457t),the protein was cleaved with cyanogen bromide. SDS-PAGE analysis followed by Edman degradation identified three cysteine-containing fragments which are not connected by disulfide linkages. Chemical modification of cysteines combined with matrix-assisted laser desorption ionization mass spectrometry identified disulfide bonds between cysteine 1 (aa 127) and cysteine 2 (aa 144) and between cysteine 3 (aa 286) and cysteine 4 (aa 347). Further proteolysis of the cyanogen bromide-generated fragment containing cysteine 5 through cysteine 8, combined with mass spectrometry and Edman degradation, showed that disulfide bonds link cysteine 5 (aa 386) to cysteine 8 (aa 442) and cysteine 6 (aa 390) to cysteine 7 (aa 419). A similar disulfide bond arrangement is postulated to exist in gC homologs from other herpesviruses.  相似文献   
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In 3 experiments, the nature of the events that interfere with spatial working memory was examined in order to clarify the roles of imagery, attention. and other processes in the short-term maintenance of location information. Looking and pointing at secondary task stimuli selectively interfered with memory for the locations of primary task stimuli. Secondary tasks that involved either mentally rotating primary task stimuli or making color or shape discriminations about primary or secondary task stimuli interfered with spatial working memory only if the required response was visually guided, but not if the response was verbal. Taken together, these findings support P. S. Goldman-Rakic's (1987) hypothesis regarding multiple representational domains and are consistent with known properties and connections of neurons believed to subserve the perception and maintenance of spatial information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
PURPOSE: To determine the ease of use by clinical staff and reliability of an electronic portal imaging system and evaluate the potential to utilize on-line imaging to assess accuracy of daily patient treatment positioning in radiation therapy. METHODS AND MATERIALS: A computer controlled fluorescent screen-mirror imaging system was used to acquire on-line portal images. A physician panel assessed on-line image quality relative to standard portal film. Clinical use of the imager was implemented through a protocol where images were obtained during the first six monitor units of external beam. The images were visually compared to a reference portal and patient setup was adjusted for errors exceeding 5 mm. Subsequent off-line analysis was utilized to give insight into the magnitude of clinical setup error in the visually accepted images. RESULTS: Physician evaluation of on-line image quality with an initial 211 images found that 70% were comparable or superior to standard film portal images. Eighty percent of treatment fields fit completely within the on-line imaging area. Eight percent of on-line images were rejected due to poor image quality. Twelve percent of the daily treatment setups imaged required adjustment overall, but specific field types predictably required more frequent adjustment (pelvic and mantle fields). Off-line analysis of accepted images demonstrates that 18% of the final images had setup errors exceeding 5 mm. CONCLUSION: On-line imaging facilitated daily portal alignment and verification. Ease of use, almost instantaneous viewing and consistent ability to identify and locate anatomical landmarks imply the potential for on-line imaging to replace film based approaches. Retrospective analysis of daily images reveals that visual assessment of setup is not sufficient for eliminating localization errors. Further improvement is required with respect to detecting localization error and fully encompassing larger field sizes.  相似文献   
45.
The efficacy of hydroxyzine and buspirone, controlled by placebo, was investigated in a double-blind, parallel group, multicentre study conducted in France and the UK. A total of 244 patients with generalised anxiety disorder in primary care was allocated randomly to treatments with hydroxyzine (12.5 mg morning and mid-day, 25 mg evening), buspirone (5 mg morning and mid-day, 10 mg evening) or placebo (three capsules/day) for 4 weeks, preceded by a 1-week single-blind placebo run-in and followed by 1-week single-blind placebo administration. Rating scales were applied on days -7,0,7,14, 12,28 and 35. Seventy percent of the patients were female, the average age was 41 +/- 11 years, and the mean Hamilton Anxiety Score at day 0 was 26.5 +/- 4.2. Only 31 of the 244 patients dropped out, but equally in the three groups. Intention-to-treat LOCF analyses on the primary variable showed a significant difference only between hydroxyzine and placebo with respect to improvement on the Hamilton Anxiety Scale (10.75 versus 7.23 points, respectively). Secondary variables such as CGI and self-ratings (HAD scale) showed both hydroxyzine and buspirone to be more efficacious than placebo. Thus, hydroxyzine is a useful treatment for GAD.  相似文献   
46.
Aging and movement: Variability of force pulses for saccadic eye movements.   总被引:1,自引:0,他引:1  
Age-related differences in the trajectories of saccadic eye movements were examined. Younger and older adult subjects produced saccades to predictable target locations. Detailed features of the movements were examined such as the time of peak acceleration and the variability in the magnitude of the peak velocity. These and other measures reveal important details of the force pulses underlying the eye movements and the mental mechanisms that control them. Although minor differences were apparent between the eye movements of younger and older adults, the general patterns were the same across age groups. These results suggest that fundamental details of the brain mechanisms involved in the control of movement are the same for younger and older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Chitra analyzes a program execution sequence (PES) collected during execution of a program and produces a homogeneous, semi-Markov chain model fitting the PES. The PES represents the evolution of a program state vector in time. Therefore Chitra analyzes the time-dependent behavior of a program. The authors describe a set of transforms that map a PES to a simplified PES. Because the transforms are program-independent. Chitra can be used with any program. Chitra provides a visualization of PESs and transforms, to allow a user to visually guide transform selection in an effort to generate a simple yet accurate semi-Markov chain model. The resultant chain can predict performance at program parameters different than those used in the input PES, and the chain structure can diagnose performance problems  相似文献   
50.
In the past, remote sensing from aircraft and satellite for geologic mapping concentrated on the visible and reflective infrared parts of the spectrum, because of the availability of Landsat and aircraft multispectral scanners operating in this spectral range. With the launch of the Heat Capacity Mapping Mission (HCMM) satellite, regional thermal image data also became available. We have examined the HCMM data for geologic information over two desert areas in southern California, the Trona area and the Pisgah area. Three techniques were used for displaying and combining thermal data and visible and near infrared, including color additive composites, principal components, and calculation of thermal inertia images. Use of the color additive composite image was simplest and allowed for simultaneous display of both thermal and reflectance properties. Thermal data were found to provide additional geologic information, unavailable from Landsat data or from aircraft visible and near-infrared data alone. The addition of these data relating to thermal properties allowed separation of rock types with differing thermal properties but with similar reflectance characteristics.  相似文献   
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