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51.
The cloning of BRCA1, a susceptibility gene for inherited breast cancer, has made genetic screening possible for individuals and families whose medical histories are suggestive of an inherited predisposition to breast cancer. To date, few systematic attempts have been made to determine the level of knowledge about breast cancer genetics among women who are likely to seek BRCA1 screening when it becomes widely available. The present study attempted to assess the general knowledge about BRCA1 mutations in two groups: (1) first-degree relatives (FDRs) of breast cancer patients; and (2) women with a previous diagnosis of breast cancer. A self-administered, thirty-item questionnaire was developed through a pilot study. Ten of the items were objective, factual questions about breast cancer genetics. Responses to these questions were used to generate an overall knowledge score for each respondent. The study population was moderately knowledgeable about breast cancer genetics, with an average score of 5.35 out of 10. Counselors should not underestimate the importance of evaluating each counselee's existing knowledge about breast cancer, which can affect the provision and reception of genetic information. In particular, specific areas of knowledge that may be confusing or misunderstood were identified and these topics are discussed in detail. 相似文献
52.
实验用实字、虚字、与被试自身相关字三类汉字作刺激材料,将直接测量(再认任务)和间接测量(喜好判断任务)进行匹配,考察了被试对不同类别汉字在两种测量方式中的反应。结果发现:实字和虚字间在各种不同的实验处理中均未表现出明显的差异;中性汉字和自我关联汉字都在直接测量的两种注意水平间产生了显著差异,而在间接测量时未产生显著差异;“拥有效应”的作用不是单向的,当自我关联汉字处于注意焦点以外的位置时,直接测量出现了反转的结果。 相似文献
53.
自由回忆和线索回忆测验中的系列位置效应 总被引:3,自引:1,他引:2
本文以96个中国汉字为材料,使用自由回忆和线索回忆测验方法,对20名被试进行6组分测验和最后所有汉字的总测验。发现自由回忆分测验中存在明显的系列位置效应,总测验出现负近因现象;线索回忆分测验也表现出明显的系列位置效应,但最后的总测验没有出现负近因现象。上述结果验证了Bjork和Whitten(1974)提出的顺序或情景理论。 相似文献
54.
小学儿童对习俗时间的周期性特点的认知 总被引:2,自引:0,他引:2
本研究探讨了小学儿童对习俗时间周期性特点的认知发展.实验任务是让被试判断两个给定日期之间的时间距离是正向接近还是反向接近。结果表明:儿童对习俗时间的周期性特点的认知成绩随年龄增长而不断提高;随着两个日期之间距离的增大,反应时不断增加,正确率不断降低,在两个日期相互接近的方向发生改变的边界处,反应时最长,正确率最低,表现出显著的“距离效应”和“边界效应”;儿童可以利用数字系统进行判断,他们的认知加工策略包括计数、数字运算和凭借习俗时间的空间表象进行模拟加工等等。 相似文献
55.
人性观对心理学理论与研究的影响 总被引:5,自引:0,他引:5
心理学的基本理论,尤其是人格理论,通常都蕴含着对人性的假设。人性观的差异常常导致其理论建构的差异。而且人性观影响心理学研究的方式、方法,影响对心理成因的认识、对心理疾病的理解、及对异常矫正策略的选择。 相似文献
56.
57.
The self-injurious escape behavior of a developmentally disabled adult was treated with extinction. Results of a reversal design showed substantial bursts of responding when extinction was introduced and reintroduced: self-injury remained at a variable and elevated rate for some time before stable, low rates were observed. Data on aggression, a nontarget behavior during both baseline and treatment, showed a pattern similar to that seen for self-injury during the extinction conditions. 相似文献
58.
Rats were trained on concurrent schedules under which responses on one lever postponed shock (avoidance) and responses on the other lever produced brief (2-min) periods of signaled timeout from avoidance. For 6 rats, timeout from avoidance was programmed on a variable-interval 45-s schedule that generally resulted in rates that were lower than those on the avoidance lever. For another 6 rats, timeout was arranged on a variable-ratio 15 schedule that produced higher baseline rates. Cocaine (3 to 40 mg/kg) produced large, dose-dependent increases in behavior maintained by timeout in both groups of rats. Avoidance responding was also generally increased by cocaine, but the increases were of lesser magnitude. Increases in response rates were seen across a broad range of doses on behavior maintained by either interval or ratio schedules, an outcome that was unexpected on the basis of most studies of cocaine on food-maintained behavior. These results were similar to those of previous studies of the effects of amphetamine on behavior maintained by timeout from avoidance and suggest that stimulant drugs affect behavior maintained under a shock-postponement schedule differently than they affect behavior maintained by timeout from avoidance. 相似文献
59.
When the process of publication favors studies with smallp-values, and hence large effect estimates, combined estimates from many studies may be biased. This paper describes a model for estimation of effect size when there is selection based on one-tailedp-values. The model employs the method of maximum likelihood in the context of a mixed (fixed and random) effects general linear model for effect sizes. It offers a test for the presence of publication bias, and corrected estimates of the parameters of the linear model for effect magnitude. The model is illustrated using a well-known data set on the benefits of psychotherapy.Authors' note: The contributions of the authors are considered equal, and the order of authorship was chosen to be reverse-alphabetical. 相似文献
60.
Genetic counseling for women of advanced maternal age who are considering prenatal testing continues to be based on a principle of nondirectiveness. We interviewed 11 genetic counseling students and four counselors about how they experience and manage, in practice, the tensions between the ideology of nondirectiveness and the acknowledged reality that one can never be truly nondirective. We found that our respondents creatively resolve this tension—simultaneously resisting and adhering to the values of nondirectiveness and information-giving—in individual and situation-specific ways. This resolution is facilitated by the extent to which information given to counselees is fluid, mobile and context-dependent, but these very features of information also have critical implications for both the norms and the practice of genetic counseling. 相似文献