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21.
Normal cerebral perfusion measurements using arterial spin labeling: reproducibility, stability, and age and gender effects. 总被引:4,自引:0,他引:4
Laura M Parkes Waqar Rashid Declan T Chard Paul S Tofts 《Magnetic resonance in medicine》2004,51(4):736-743
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males. 相似文献
22.
Siu Fai Li MD Nashat Latib MD Angela Kwong MD Shreni Zinzuwadia MD Ethan Cowan MD 《Academic emergency medicine》2007,14(12):1194-1196
Background In recent years, the number of women entering the field of emergency medicine (EM) has increased.
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献
23.
中美中学生对由父母原因引起的考试焦虑认知研究 总被引:1,自引:0,他引:1
目的:比较中国和美国的中学生对由父母原因引起的考试焦虑的认知情况。方法:采用“失败结果预期(FOE)”问卷中的由父母原因引起的考试焦虑12项,测量中美两国公立学校14、15岁的1215名中学生对考试焦虑原因的认知。结果:1.相似认知:两国学生在由父母原因引起的考试焦虑方面有类似的认知,包括父母会担心自己能否进入高一级学校、会让父母烦恼等。2.跨文化的差异:表现为中国学生更多是因为父母责备、辜负了父母期望或会让父母生气而导致考试焦虑;而美国学生更多是由于父母认为他们不能面对生活中的挑战而产生焦虑。3.性别差异:表现在美国的女中学生在7个项目上、中国的男中学生在2个项目上分别比本国异性有更大程度的焦虑(P〈0.05)。结论:中美中学生对由父母原因引起的考试焦虑方面有类似的认知,但存在文化差异和性别差异。 相似文献
24.
The current study evaluated psychosocial variables that may contribute to the experience of headache in college adults. One hundred ninety-nine participants, 103 women and 96 men, completed head pain logs for 4 weeks after completing measures assessing psychosocial variables. Multiple regression analyses indicated that level of emotional functioning, perception of stress, and gender were predictive of future headache frequency, intensity, and duration. Family history and health habits did not predict headache activity. These findings are consistent with research investigating psychosocial variables and headache activity. 相似文献
25.
B. K. Suarez C. L. Hampe A. Parsian C. R. Cloninger 《American journal of medical genetics. Part A》1995,60(5):417-423
Thirty-five alcoholic families have been studied to investigate the relationship between DNA markers at the monoamine oxidase (MAO) loci and (1) platelet activity levels and (2) alcoholism. A quantitative linkage analysis failed to reveal any evidence that the variation in activity levels cosegregates with the DNA markers. A sib-pair analysis did not reveal a significant excess of MAO haplotype sharing among alcoholic sibs, although the deviation from random sharing was in the direction consistent with an X-linked component. A reanalysis of platelet MAO activity levels in a subset of these families revealed that the lower levels previously found in alcoholics is more likely due to the differences between males and females. Only among males and only when a “broad” definition of alcoholism is used (and MAO activity levels are transformed to normality) does it appear that alcoholics have depressed activities compared to nonalcoholics. Finally, when the confounding due to gender difference is removed, no differences between type I and type II alcoholics are found in these families. © 1995 Wiley-Liss, Inc. 相似文献
26.
The moderator effect of gender on (i) the relation between adolescents' sexual experience on the one hand; and (ii) their orientations towards the type of relational and emotional commitment that they expect to be present before engaging in a sexual relationship, and (iii) having a steady partner on the other was examined. We hypothesized that the relations between these facets would be stronger for women. We utilized a random sample of 253 British adolescents interviewed twice with a 1-year interval LISREL multigroup analysis with mean structures was used to test the hypotheses, thus offering the opportunity of detecting moderator as well as main effects of gender. Differential effects of emotional and relational commitment and having a steady partner relationship on sexual experience supported the hypotheses. 相似文献
27.
Louisa Sims 《Early child development and care》1994,98(1):79-96
This study examines young children's perceptions of work through a specific example. Reception class children at an inner city school were shown pictures of the same figure washing in four different contexts, ranging from housework to paid employment, in order to examine early classifications and conceptual systems relating to the concept of work and to ascertain whether these were gender related. Individual children varied in the complexity of their ideas, but the majority had not yet began to form hierarchical classifications of work which favour paid employment. There was evidence however that some children were beginning to devalue traditional women's work, suggesting that gender stereotypes are still prevalent amongst this age group, despite efforts by the educational system to counter this. 相似文献
28.
Vern L. Bullough Ph.D. 《Archives of sexual behavior》1987,16(1):81-84
An 1897 clinical case of transsexualism before the diagnostic category was established is described. It was reported by a Baltimore physician trying to introduce concepts of homosexuality to the psychiatric community. 相似文献
29.
C. Pozzilli V. Tomassini F. Marinelli A. Paolillo C. Gasperini S. Bastianello 《European journal of neurology》2003,10(1):95-97
The authors evaluated the gender difference in the magnetic resonance imaging characteristics of the lesions occurring in the brain of 413 multiple sclerosis (MS) patients. Men had fewer contrast-enhancing lesions (P = 0.01), but a higher proportion of lesions evolving into 'black holes' (P = 0.001), when compared with women. Thus, our data indicate that men with MS are prone to develop less inflammatory, but more destructive lesions than women. This study results provides support for a modulation of the MS pathological changes by gender. 相似文献
30.
Debra Siela 《Rehabilitation nursing》2003,28(6):197-204
This correlational and comparative study explored whether self-reports of self-efficacy and dyspnea perceptions predict the perceived level of functional performance in adults who have chronic obstructive pulmonary disease (COPD). The convenience sample included 97 Caucasian men (52) and women (45). Participants had to have a forced expiratory volume in 1 second (FEV1) of less than 70% predicted, and a FEV1/forced vital capacity (FVC) of less than 70%. Participants were recruited from pulmonary function laboratories and from better breather support groups in a Midwestern state. Three standardized, self-report instruments, COPD Self-Efficacy Scale (CSES), the Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ), and Functional Performance Inventory (FPI) were used to measure the participants' self-report of their perceptions of self-efficacy, dyspnea, and functional performance. Dyspnea predicted 38.1% of the variance in functional performance, with self-efficacy contributing an additional 6.5% to the variance in the total sample. Self-efficacy predicted 36.5% of the variance in functional performance in men, with dyspnea contributing an additional 7.2% to the variance. However, in women, only dyspnea was a significant predictor of functional performance, at 48.5% when both dyspnea and self-efficacy were entered as independent variables. To improve patients' perceptions of functional performance, nurses can use methods such as breathing techniques and upper- and lower-body exercises that increase optimal management of dyspnea. Nurses may increase the self-efficacy of managing dyspnea by helping patients master breathing techniques and exercise through coaching and providing vicarious experiences through patient support groups or pulmonary rehabilitation programs. 相似文献