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As interpreters for their deaf parents, hearing children are a cultural link between two often separate worlds: the Deaf and the Hearing. Data from a 4 year study of adult hearing children throughout the United States indicate significant differences between hearing daughters and hearing sons. Not only were daughters more likely than sons (regardless of birth order or age differences) to interpret for their parents, but daughters were also far more likely to be bilingual: fluent in both spoken English and American Sign Language. A similar gender bias has been observed among the general hearing public: women are far more likely to attend sign language classes and to work as interpreters for the deaf. This paper explores the social mechanisms and cultural values which determine the gender of the way we communicate with one another. Informants' narratives suggest that sign language and the practice of interpreting often touched upon a larger pattern of socialization and status differences between women and men. The discussion then turns to consider how these differences affect the cultural identity of hearing sons versus hearing daughters.  相似文献   
44.
Widely disseminated brief interventions against excessive drinking, as part of the new public health movement, have a potentially crucial role in reducing alcohol-related harm on a national scale. However, a number of conceptual problems and practical barriers to progress in this area can already be identified. This article focuses on the British experience of research and implementation of community-based brief interventions, which is longer than that of other countries, as a means of discussing these problems. Rather than being pessimistic about the possible impact of brief interventions, the article is based on the assumption that it is only by clearly recognizing and solving such problems that the potential of brief interventions in the alcohol field will be fully realized.  相似文献   
45.
The transient impairments of memory produced by the muscarinic antagonist scopolamine have been adopted as a pharmacological model of Alzheimer-type dementia in normal volunteers. In this study we examined the effects of chronic (72 h) transdermal administration of scopolamine on memory, attention, sedation and visual function. The transdermal patches provided constant plasma levels of scopolamine for the duration of the study. Indices of the peripheral effects of scopolamine (visual near-point and pupil size) showed impairments that were sustained for 3 days. However, measures of sedation and memory revealed impairments that were maximal the day after patch application and which were no longer present 3 days after application. This pattern of results is discussed in relation to pharmacological modelling of Alzheimer's disease.  相似文献   
46.
Two simian Epstein-Barr-like viruses, a rhesus Epstein-Barr virus and Herpesvirus papio, were used to transform B cells from rhesus or cynomolgus macaques. The resulting cell lines exhibited predominantly a B lymphocyte phenotype and expressed Epstein-Barr virus antigens. The majority of B lymphoblastoid cell lines from macaques, which were seropositive for simian foamy virus, developed giant cells in culture. The cytopathic agent was identified as a foamy virus and was transmissible to human embryonal fibroblasts. Treatment of cell cultures with AZT abolished giant cell formation.  相似文献   
47.
With the increasing recognition of attention deficit hyperactivity disorder (ADHD) in adults and psychotic disorders in children and adolescents, the possibility of a relationship between bipolar disorder (BP) and ADHD has attracted growing interest. This paper critically reviews the scientific literature concerning this postulated relationship by examining evidence from clinico-epidemiological, follow up, family and laboratory studies, including neuroimaging, neuropsychology and genetic studies. The evidence suggests that although the diagnostic categories of BP and ADHD appear to be unrelated, there is support for a possible relationship between some ADHD and manic-like symptoms. However, several fundamental methodological issues require rectification in future research in order to further elucidate the relationship between these disorders.  相似文献   
48.
Candidate gene analysis in human neural tube defects   总被引:4,自引:0,他引:4  
Biochemical and developmental pathways, mouse models, and positional evidence have provided numerous candidate genes for the study of human neural tube defects. In a survey of 80 studies on 38 candidate genes, few found significant results in human populations through case-control or family-based association studies. While the folate pathway has been explored extensively, only the MTHFR 677C > T polymorphism was significant, and only in an Irish population. Developmental pathways such as the Wnt signaling pathway and Hox genes have also been explored without positive results. More than 90 mouse candidates have been identified through spontaneous and knockout mutations, but only the T locus (mouse Brachyury gene) showed association in an initial study that was not confirmed on follow-up. Positional candidates have been derived from cytogenetic evidence, but preliminary genomic screens have limited power due to small sample sizes. Future studies would increase their power to detect association by using more samples. In addition a clarification of the phenotype would be beneficial as many studies used different inclusion criteria. Incorporating several types of data could highlight better candidates, as would looking beyond the traditional sources for candidate genes. Recent studies of an energy metabolism gene (UCP2) and vitamin B metabolism (Transcoalbumin) have produced promising results. Utilizing other model organisms may also be beneficial, as in a recent study from a chick model of NTDs in NCAM1. New approaches combined with traditional methods and increased sample sizes will help prioritize human NTD candidate genes and clarify the complex etiology of this condition.  相似文献   
49.
Bipolar women have a marked vulnerability to puerperal psychosis, an episode of mania or psychosis following childbirth. We have conducted a family history study to examine the question of whether a vulnerability to puerperal episodes of illness is a marker for a more familial form of bipolar disorder. A consecutive series of 103 bipolar disorder probands were recruited in a lithium clinic and given a semi-structured interview, including a detailed family history. For the 52 female probands, information was also obtained about the relationship of episodes to childbirth. The morbid risk of affective disorder in first-degree relatives of bipolar women who had suffered an episode of mania, hypomania or schizoaffective mania with onset within 6 weeks of childbirth was significantly higher than that in relatives of parous bipolar women with no episodes in relation to childbirth (P = 0.0077). Despite relatively small numbers, this study provides evidence to support the hypothesis that puerperal episodes identify a more familial subtype of bipolar disorder.  相似文献   
50.
Cholinergic postganglionic neurones of the cardiac vagus in the toad, Bufo marinus, have been shown to contain the peptide somatostatin (SOM), which causes direct negative inotropic and chronotropic effects on the heart. In anaesthetised toads, high frequency stimulation (10 Hz) of cardiac vagus nerves results in prolonged cardiac slowing and potentiation of the cardiac slowing measured in response to a train of vagal stimuli at low frequency. Intravenous administration of the tetradecapeptide form of SOM also results in prolonged cardiac slowing and potentiation of cardiac vagal action. Effects on heart rate of small bolus doses of acetylcholine (ACh) were unaltered by administration of SOM, at the same time as cardiac vagal slowing was enhanced. It is suggested that SOM is released from vagal nerve endings by high frequency stimulation and enhances cardiac vagal action by a presynaptic mechanism.  相似文献   
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