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991.
Regine WF Huhn JL Patchell RA St Clair WH Strottmann J Meigooni A Sanders M Young AB 《International journal of radiation oncology, biology, physics》2002,52(2):333-338
PURPOSE: A single-institution experience using primary stereotactic radiosurgery (SRS) alone in the management of newly diagnosed brain metastases was analyzed to identify the risk of symptomatic brain tumor recurrence (BTR) and neurologic deficit associated with such a treatment strategy. METHODS AND MATERIALS: Thirty-six patients were treated for newly diagnosed single/multiple brain metastases using SRS alone followed by planned observation. SRS minimum tumor dose ranged from 8 to 25 Gy (median: 20 Gy). Factors evaluated in analysis of treatment outcome included number of metastases, site of metastasis, primary tumor site, histology, extent of intracranial and extracranial disease, and interval to diagnosis of brain metastasis. RESULTS: Median and 1-year survival for the entire group was 9 months and 36%, respectively. BTR anywhere in the brain occurred in 47% (17/36) of patients. Forty-seven percent of BTR (8/17) recurred at the site of original metastasis; 35% (6/17) recurred at both original [corrected] and distant sites in the brain, and 18% (3/17) recurred at distant only [corrected] brain sites. Seventy-one percent (12/17) of the patients were symptomatic at the time of recurrence, and 59% (10/17) had an associated neurologic deficit. Multivariate analysis found that only the extent of disease was a predictor of BTR. Patients who had disease limited to the brain only had a BTR rate of 80% (8/10) vs. 35% (9/26) who had disease involving the brain, primary site, and/or other extracranial metastatic sites (p = 0.03). CONCLUSIONS: Use of primary SRS alone in this setting is associated with an increasingly significant risk of BTR with increasing survival time. In addition, the majority of such recurrences are symptomatic and associated with a neurologic deficit, a finding not analyzed in recently reported experiences withholding whole brain radiation therapy as part of the primary treatment of brain metastasis. 相似文献
992.
La Russa VF Schwarzenberger P Miller A Agrawal K Kolls J Weiner R 《Cancer investigation》2002,20(1):110-123
993.
Roy A 《Journal of psychiatric research》2002,36(3):173-177
OBJECTIVE: To examine whether childhood trauma may have a relationship to hypothalamic-pituitary-adrenal (HPA) axis function as an adult. METHODS: Forty-six withdrawn cocaine dependent patients participated in 24-h urine collections for determination of urinary-free cortisol (UFC) and completed the Childhood Trauma Questionnaire (CTQ). RESULTS: Patients with a mean UFC output below the median had significantly higher CTQ scores for childhood sexual abuse than patients with UFC outputs above the median. Multiple regression analysis showed that both childhood emotional neglect and sexual abuse were independently associated with UFC outputs. CONCLUSION: These cross sectional data, in a sample of middle-aged cocaine dependent patients, suggest the possibility that childhood trauma may have an effect on HPA axis function and thus predispose to psychiatric disorders. Further studies are needed in different samples. 相似文献
994.
It is claimed that Alzheimer's disease (AD) patients show reduced inhibitory processing and this has been put forward as a reason why AD patients make intrusion errors at recall. However, the evidence to date has been equivocal, because non-inhibitory mechanisms can account for the pattern of findings. Recently, however, a paradigm has been developed that is claimed to give a purer measure of inhibitory processing in episodic memory, the retrieval-induced forgetting (RIF) paradigm [Inhibitory Processes in Attention, Memory and Language, Academic Press, San Diego, 1994, p. 265; J. Exp. Psychol.: Learning, Memory Cognition 20 (1994) 1063; Psychol. Rev. 102 (1995) 68]. Thus, we were interested whether AD patients would show a deficit in inhibitory processing using this procedure. Participants studied lists of category cue-exemplar pairs (e.g. fruit-orange) then practised retrieval for a subset of items from a subset of categories before taking a final memory test for all studied items. As in previous work, inhibition was measured as the difference between final memory performance for unpractised items from practised categories, and unpractised items from unpractised categories. The results show that AD patients showed normal levels of inhibition with both tests of cued recall and category generation (CG). This suggests that a deficit in inhibitory processes during retrieval is not behind the high levels of intrusion errors made in recall in AD. 相似文献
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996.
OBJECTIVE: Depression is currently modelled dimensionally, along severity, duration and recurrency dimensions. An alternative model allows dimensional expressions of temperament and personality to influence risk to onset as well as persistence. Here, we examine the utility of a temperament model. METHOD: A questionnaire assessing temperament dimensions and a number of depression variables was administered to a large routine general practice sample and with the temperament measure also completed by a small clinical sample. RESULTS: 'Anxious worrying' and 'irritable' dimensions were identified as internalizing and externalizing expressions of a trait anxiety dimension, three other 'temperament' dimensions (i.e. 'introversion', 'self-centred' and 'obsessive') were refined, while a 'self-blame' dimension intruded into the factor analytic solution. High scores on the 'anxious worrying' dimension were associated with all depression parameters. The 'irritable', 'introversion' and 'self-blame' dimensions were less clearly linked with depression variables, while higher scores on the 'self-centred' and 'obsessional' dimensions did not appear to increase the chance of depression onset, persistence or recourse to treatment. CONCLUSION: A temperament-based approach appears to have some conceptual utility in modelling depression, and particularly, the non-melancholic disorders. It is likely, however, to require complementing with refined at-risk personality dimensions. 相似文献
997.
Roy A Berman J Williams R Kuhn C Gonzalez B 《The American journal of psychiatry》2002,159(6):1053-1055
OBJECTIVE: The authors examined an index of dopaminergic neurotransmission in recently abstinent cocaine-dependent patients. METHOD: CSF concentrations of the dopamine metabolite homovanillic acid (HVA) were determined in 30 recently abstinent cocaine-dependent patients and 69 healthy comparison subjects. RESULTS: The cocaine-dependent patients had a significantly higher mean concentration of CSF HVA than did the healthy comparison group. CONCLUSIONS: Recently abstinent cocaine-dependent patients may show dysregulation of the central dopaminergic system. 相似文献
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Several recent studies support Katz's hypothesis that vibrotaction plays a role in the perception of tactile textures with elements too small and closely spaced to be processed spatially. For example, eliminating vibration by preventing movement of a stimulus surface across the skin compromises psychophysical scaling and discrimination of fine, but not coarse, textures. Fine-texture discrimination is also impaired when vibrotactile channels are desensitized by adaptation. A role for vibrotaction in texture perception is plausible, given the keenness of this submodality: the sensory qualities produced by a sinusoidal vibration uniquely specify its frequency and amplitude, and subjects can distinguish some complex vibrations that differ in waveform but have the same spectral components. Finally, imposed vibration can modify the perceived texture of a haptically-examined surface. Taken together, these lines of evidence support the view that vibrotaction is both necessary and sufficient for the perception of fine tactile textures. 相似文献