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231.
Chiari type I malformation has traditionally been defined as a downward herniation of the cerebellar tonsils of 5 mm through the foramen magnum and it is likely associated with a volumetrically reduced posterior fossa. Syringomyelia is commonly associated with Chiari type I malformation. We estimate the prevalence of these two conditions and determine that they are more common than previously expected. We identify the genetic syndromes associated with some cases of Chiari type I malformation, and we provide evidence in favor of a genetic hypothesis for at least a subset of the nonsyndromic cases.  相似文献   
232.
The behavior of male mice from two BALB strains, the BALB/cJ strain and the BALB/cByJ strain, was examined with a social behavior test and a resident-intruder paradigm. Prior to testing, the animals were isolated for 0, 2, 5, or 10 days. In the social behavior test the pairs of BALB/cJ mice spent more time in active social interaction than pairs of BALB/cByJ mice, although the latter strain showed more locomotor activity. BALB/cJ mice isolated for 5–10 days, when tested in a familiar environment were more aggressive than mice from the BALB/cByJ strain. In the resident-intruder paradigm, in which a resident BALB mouse was confronted with an intruder NIH Swiss mouse, the BALB/cByJ mice showed more social investigation in their home cage towards the intruders, but there were no significant differences between the two strains in the amounts of aggressive behavior exhibited. The results of these experiments suggest that there are some differences in the social behavior of the genetically related BALB/cJ and BALB/cByJ mice. However, the differences appear subtle and paradigm-specific.  相似文献   
233.
234.
Challenge studies are often implemented for assessing whether a subject is sensitive to a certain agent or allergen. In particular, researchers test groups of subjects to determine if there really exists a causal relationship between some agent of interest and a response. To answer such a question, we need to detect the presence of the phenomenon in just one individual. Typically, however, there are a large number of unknown risk factors associated with the response and a potentially small population prevalence. Hence, standard statistical techniques, by averaging the treatment effect across the group, may miss a significant response of a single individual and lead to inconclusive results. We develop an alternative approach based on union-intersection testing that will allow a practitioner to correctly examine observations on an individual apart from the other subjects and test the hypothesis of interest: Does the phenomenon exist in the population? More specifically, we show how this technique adjusts for the multiple number of tests encountered when analyzing data for each individual subject separately. Furthermore, we demonstrate power calculations for the determination of sample size prior to performing the study. The performance of the union-intersection approach in comparison to linear models and semiparametric techniques is considered through sample size calculations and simulations. The union-intersection testing methodology out performs the Kolmogorov tests. However, the nested linear model performs as well if not better than the union-intersection tests. To illustrate the ideas presented in the paper, we provide an application in which we analyze psychological data collected by way of a challenge study design.  相似文献   
235.
Breast Cancer Risk Analysis, a service for women with breast cancer and their families, makes use of information drawn from fields such as genetics, epidemiology, and counseling. Its aim is to provide individuals with background information and information regarding the etiology and risks of breast cancer. Based on this information, individuals are helped to make appropriate decisions pertaining to treatment and follow-up. While making use of some of the information and processes used in genetic counseling, Breast Cancer Risk Analysis differs from most types of genetic counseling for reproductive decisions. Some of these differences are discussed here.  相似文献   
236.
In response to 1982 legislation and 1984 changes in the Wisconsin Adoption Records Laws requiring the collection of a medical-genetic history at the time of termination of parental rights, a continuing education program in genetics was conducted for adoption workers in 1984 and 1985. The education program provided 14 workshops in five locations throughout the state and consisted of a variety of formats and levels of training. In all, 164 participants were trained at least at the introductory level with approximately 40 of these individuals taking part in the advanced levels of training. Evaluations of the training by participants and by a sample of the agency supervisors of trainees ranked the program very highly. A review of genetic history forms completed in post-training sessions verified the expectation that training was beneficial. Trained workers completing the medical-genetic history forms scored somewhat higher than untrained workers and much higher than parents who completed the forms without professional guidance. Medical-genetic history forms completed by birth fathers as part of step-parent adoptions contained little to no useful information about the birth father's genetic background.  相似文献   
237.
Genetic factors appear to be of considerable importance in determining normal variation in personality. This is suggested by family, twin, and adoption studies as well as by indirect findings based on animal and psychophysiological studies. In contrast, there is consistent evidence that the contribution of shared family environment is minimal. Despite difficulties in defining personality disorder, it appears that many types of personality disorder, in particular schizotypal personality disorder and antisocial personality disorder/criminality, are also influenced genetically. The genetic transmission of normal personality traits and disorder is most easily explained by the contribution of multiple genes of small effect rather than by single-gene inheritance. Recent advances in molecular genetics have led to the localization of genes of minor effect for some traits. This raises the possibility of detecting a molecular basis of traits and disorders such as personality and personality disorder.Anita Thapar is supported by a Research Training Fellowship from the Medical Research Council.  相似文献   
238.
Lindon Eaves 《Zygon》1991,26(4):495-503
Abstract. Arthur Peacocke's seminal contribution to the dialogue between science and theology is considered along three dimensions: epistemology, anthropology, and the concept of God. It is suggested that his view of a "hierarchy of disciplines" (1) may not completely characterize the way theology interacts with science, and (2) could limit the creative friction between them. His emphasis on humans as "more than" DNA could result in an anthropology that fails to exploit insights that biology could shed on theological puzzles as the impact of genetics is more widely appreciated. His concept of God may also need to be modified more radically to express our understanding of nature in an age of genetics.  相似文献   
239.
庄建程  刘艳芳  张侃 《心理学报》1998,31(2):143-148
该文运用相容性研究中的维度重叠模型以及Fork-Join网络模型,得出群体模板的相容性定义与S-R相容性的元素匹配之间的关系式,详细讨论了汉字编码输入法研究中的学习遍数、反应时与汉字部件-英文字母相容性的关系,理论模拟与实验所显示的趋势符合。  相似文献   
240.
In the self‐worth model, burnout is considered to be a syndrome of performance‐based self‐esteem (PBSE) and experiences of exhaustion. Studies have shown that PBSE and burnout indices such as Pines’ Burnout Measure (BM) are associated. Whether these variables have overlapping etiologies has however not been studied before. Genetic and environmental components of covariation between PBSE and exhaustion measured with Pines’ BM were examined in a bivariate Cholesky model using data from 14,875 monozygotic and dizygotic Swedish twins. Fifty‐two per cent of the phenotypic correlation (r = 0.41) between PBSE and Pines’ BM was explained by genetics and 48% by environmental factors. The findings of the present study strengthen the assumption that PBSE should be considered in the burnout process as proposed by the self‐worth conception of burnout. The present results extend our understanding of the link between this contingent self‐esteem construct and exhaustion and provide additional information about the underlying mechanisms in terms of genetics and environment. This finding corroborates the assumed syndrome view on burnout, while it also suggests an altered view of how the syndrome emerges and how it can be alleviated.  相似文献   
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