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The acute psychological reactions of 101 train drivers to on-the-track accidents were studied by means of clinical interviews and questionnaires (Impact of Event Scale, GHQ-20 and a questionnaire addressing stress symptoms, pre-accident expectancies and worries). More than half of the train drivers reported moderate to high intrusive distress (mean 11.3) within hours to days after the accident but only 1/3 reported symptoms of acute psychophysiological arousal. Intrusive symptoms related to visual impressions were most frequently reported. Avoidance was less prevalent (mean 8.8).

Clinical interviews, relationship between pre-accident worries and severity of the acute responses and positive correlation between GHQ-scores relating to the fortnight preceding the accident and IES-intrusion scores, suggest that premorbid variables may influence the stress response. Involvement in more than two previous accidents invoked a feeling of vulnerability and produced stronger acute responses. Post-accident experiences involving various personal contacts did not correlate with the stress responses in this study and only a few drivers experienced such events in a negative way. Denial of the possibility of being involved in accidents was not associated with increased risk of strong acute responses, indicating that denial does not predict poor outcome in healthy persons exposed to situations where possibility of avoiding the event is outside the control of the person.  相似文献   

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Hypnosis and cognitive-behavioral packages are effective in preparing pediatric oncology patients for bone marrow aspiration and lumbar puncture. However, the relative efficacy of different preparations has not been determined, and potent components of preparation packages have yet to be identified. Further, factors hypothesized to moderate effectiveness of preparation (e.g., cognitive development) have not been investigated. Finally, due to a failure to employ process measures, the extent to which hypothesized mediators of behavior change (e.g., self-efficacy) are modified by preparation is unclear. Following an overview of empirical investigations, we make recommendations for addressing these limitations in future research.  相似文献   
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A 438 basepair intron 1 sequence adjacent to exon 2 in the human major histocompatibility complex DQA1 gene defined 16 allelic variants in 69 individuals from wide ethnic backgrounds. In contrast, the most variable coding region spanned by the 247 basepair exon 2 defined 11 allelic variants. Our phylogenetic human intron 1 tree derived by the Bootstrap algorithm reflects the same relative allelic relationships as the reported DQA1 exon 2 tree [Gyllensten and Erlich, Hum Immunol 36:1–10, 1989]. Thus 3′ DQA1 intron 1 and exon 2 have cosegregated since divergence of the human races. Comparison of human alleles to a Rhesus monkey DQA1 first intron sequence found only 10 nucleotide substitutions unique to Rhesus, with the other 428 positions (98%) found in at least one human allele. This high degree of homology reflects the evolutionary stability of intron sequences since these two species diverged over 20 million years ago. Because more intron 1 alleles exist than exon 2 alleles, these polymorphic introns can be used to improve tissue typing for transplantation, paternity testing, and forensics and to derive more complete phylogenetic trees. These results suggest that introns represent a previously underutilized polymorphic resource. © 1994 Wiley-Liss, Inc.  相似文献   
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Twenty cases of unilateral laryngeal paralysis are reported. Satisfactory follow-up intervals and data (videostroboscopy and glottographic analysis) were available on 12 patients. The excellent to normal phonatory quality achieved in many of these patients indicates that the ansa cervicalis to recurrent laryngeal nerve anastomosis is the procedure of choice in selected patients with unilateral vocal cord paralysis. Excellent medialization of the paralyzed cord, as well as correction of arytenoid malposition and thyroarytenoid muscle atrophy appear to explain the technique's success, since the reinnervated cord neither abducts nor adducts. We feel that this technique is the procedure of choice in younger patients, or those who use their voices professionally, since the phonatory quality achieved is superior to Teflon® injection or Isshiki thyroplasty, and the technique is reversible.  相似文献   
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