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201.
Although the vagus nerve has traditionally been considered to perform efferent functions, in reality it performs significant afferent functions as well, carrying information from the body, head, and neck to the brain. Preliminary studies examining this afferent activity led to the theory that vagus nerve stimulation (VNS) could successfully control seizure activity in persons who are refractory to antiepileptic medications. Unlike other forms of brain stimulation, VNS is unable to directly stimulate multiple discrete areas of the brain; however, through several pathways, it is able to relay sensory information to higher brain regions. An implantable VNS device known as the VNSTM NeuroCybernetic Prosthesis (NCP) System has been used in approximately 9,000 epilepsy patients in Europe and the United States since 1994. The implant has reduced seizure frequency by an average of 25% to 30%, with minimal side effects. Studies underway are also showing some degree of success in the management of treatment-refractory depression. The future efficacy of the implantable system in other disorders may depend on whether the implant can be more precisely focused to affect different brain regions. Research in this area is underway.  相似文献   
202.
Autistic disorder and catatonia are neuropsychiatric syndromes defined by impairments in social interaction, communication, and restricted, stereotypical motor routines. Assessments of children with these disorders are typically restricted in scope by the patients' limited ability to comprehend directions. The authors performed systematic assessments of dyskinesias on six prepubertal boys with autistic disorder and mental retardation and on one adolescent male with catatonia to determine if this type of information could be routinely obtained. The boys with autistic disorder had more stereotypies and tics, a greater degree of akathisia and hyperactivity, and more compulsions than the adolescent with catatonia. Catatonia was associated with catalepsy and dystonic postures. The authors conclude that the diagnostic accuracy and specificity of neuropsychiatric syndromes may be enhanced by the systematic assessment of the dyskinesias associated with each condition.  相似文献   
203.
The introduction of contraceptive technologies hasresulted in the separation of sex and procreation. Theintroduction of new reproductive technologies (mainlyIVF and embryo transfer) has led not only to theseparation of procreation and sex, but also to there-definition of the terms mother and family.For the purpose of this essay, I will distinguishbetween:1. the genetic mother – the donor of the egg;2. the gestational mother – she who bears and gives birth to the baby;3. the social mother – the woman who raises the child.This essay will deal only with the form of gestationalsurrogacy in which the genetic parents intend to bethe social parents, and the surrogate mother has nogenetic relationship to the child she bears anddelivers. I will raise questions regarding medicalethical aspects of surrogacy and the obligation(s) ofthe physician(s) to the parties involved. I will arguethat the gestational surrogate is “a womb to rent,”that there is great similarity between gestationalcommercial surrogacy and organ transplant marketing.Furthermore, despite claims to freedom of choice andfree marketing, I will claim that gestationalsurrogacy is a form of prostitution and slavery,exploitation of the poor and needy by those who arebetter off. The right to be a parent, although notconstitutional, is intuitive and deeply rooted.However, the issue remains whether this rightoverrules all other rights, and at what price to theparties involved. I will finally raise the followingprovocative question to society: In the interim periodbetween today's limited technology and tomorrow'sextra-corporeal gestation technology (ectogenesis),should utilizing females in PVS (persistent vehetativestate) for gestational surrogacy be sociallyacceptable/permissible – provided they have leftpermission in writing?  相似文献   
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205.
Event-related brain potentials (ERPs) of 21 subjects were recorded in a choice reaction time task with a repeating eight-element long stimulus sequence. The regular event sequence was sometimes interrupted by 'perceptual' or by 'motor deviants' which both replaced an expected stimulus but either preserved or violated the sequence of motor responses. Response times confirmed that all subjects had acquired some knowledge of the sequential dependencies. By means of a post-experimental free recall and recognition test, subjects were classified as having either explicit or implicit knowledge of the event sequence. The ERPs showed different effects for different types of stimuli and the two groups. In the group of explicit learners, a larger N200 component was evoked by both types of deviants and a larger P300 by motor deviants only. In the group of implicit learners these 'perceptual components' remained unaffected. In contrast, in both groups of subjects the lateralized readiness potential (LRP) which accompanied motor deviants revealed a partial activation of the to be expected but incorrect response, i.e. motor learning. These results suggest that explicit learners acquire knowledge about both, stimulus and response dependencies while implicit learners acquire knowledge about response dependencies only.  相似文献   
206.
The 1957 and 1976 Americans View Their Mental Health surveys from the Institute of Social Research were partially replicated in the 1996 General Social Survey (GSS) to examine the policy implications of people's responses to feeling an impending nervous breakdown. Questions about problems in modern living were added to the GSS to provide a profile of the public's view of mental health problems. Results were compared for 1957, 1976, and 1996. In 1957, 19% of respondents had experienced an impending nervous breakdown; in 1996, 26% had had this experience. Between 1957 and 1996, participants increased their use of informal social supports, decreased their use of physicians, and increased their use of nonmedical mental health professionals. These findings support policies that strengthen informal support seeking and access to effective psychosocial treatments rather than current mental health reimbursement practices, which emphasize the role of primary care physicians.  相似文献   
207.
The case history     
Case histories report the basic data of psychoanalysis, and yet they are strikingly infrequent in the psychoanalytic literature. This reflects not only the methodological problems in describing psychoanalytic cases, but also the complex intentions of psychoanalysts who want both to present and to conceal aspects of their work. The history of the case history is discussed, as are the nature and purpose of case reports, the differences between oral and written reports, the relation between case reports and psychoanalyses, and case reports as countertransferential enactments. A plea is made for including authorial intention as an explicit part of the report, rather than concealing it behind a scientific facade.  相似文献   
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209.
Modulation of the startle response was used to examine emotional processing of sexual stimulation across trials within a session. Eyeblink startle was elicited by a probe (burst of intense white noise) presented intermittently while men were viewing an erotic film segment. Repeated display of the film segment resulted in a progressive decrease in sexual arousal. Habituation of sexual arousal was accompanied by a reduction over trials in the extent the men felt absorbed when viewing the erotic stimulus and by an increase over trials in the magnitude of the eyeblink startle response. Replacing the familiar stimulus by a novel erotic stimulus increased in sexual arousal and absorption and reduced startle (novelty effect), while dishabituation was evident for all three response measures when the familiar stimulus was reintroduced. This pattern of results indicates that with repeated presentation an erotic stimulus is experienced not only as less sexually arousing but also as less appetitive and absorbing. The question of whether habituation of sexual arousal is mediated by changes in attentional and affective processing over trials is discussed, as are clinical contexts in which eyeblink startle can be used in studying aspects of sexual functioning.  相似文献   
210.
The psychometric properties of a new, 9-item scale measuring disease-specific perceptions of self-efficacy were investigated in a community-based sample of adults (N = 83) with sickle cell disease (SCD). The Sickle Cell Self-Efficacy Scale (SCSES) was comprised of nine questions relating to participants' perceptions of their ability to function on a day-to-day basis and to manage SCD symptomatology (e.g. episodes of pain). The SCSES demonstrated good internal consistency, discriminant validity, and convergent and predictive validity, both with previously validated measures of related constructs as well as with reported SCD symptomatology. Overall, the instrument appears to be reliable and valid for assessing clients' self-efficacy for engaging successfully in day-to-day activities despite having SCD. Future investigators may wish to examine temporal and causal links between alterations in self-efficacy and changes in adjustment to sickle cell disease; the SCSES provides a psychometrically sound tool with which to investigate these phenomena.  相似文献   
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