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41.
Exposing individuals to an isolated component (a prime) of a prior event alleviates its forgetting. Two experiments with 120 human infants between 3 and 18 months of age determined the minimum duration of a prime that can reactivate a forgotten memory and how long the reactivated memory persists. Infants learned an operant task, forgot it, were exposed to the prime, and later were tested for renewed retention. In Experiment 1, the minimum duration of an effective prime decreased logarithmically with age, but was always longer than the duration of a mere glance. In Experiment 2, the reactivated memory was forgotten twice as fast after a minimum-duration prime as after a full-length one, irrespective of priming delay and infant age. These data reveal that the minimum effective prime duration psychophysically equates the accessibility of forgotten memories. We conclude that priming is perceptually based with effects that are organized on a ratio (log) scale.  相似文献   
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Younis M  Vivian A  Lee JP 《Strabismus》1995,3(2):85-88
Background: The Fells modification of the Harada-lto procedure is usually performed bilaterally for the correction of excyclotorsion secondary to acquired bilateral superior oblique paresis. Excyclotorsion is not usually a major complaint in true unilateral superior oblique paresis. Occasional cases, however, may find this symptom bothersome and it may interfere with fusion. The purpose of the present study is to determine the effect of the unilateral modified Harada-lto procedure on the correction of symptomatic excyclotorsion in unilateral superior oblique paresis. Method: A retrospective case-note review of patients with unilateral superior oblique paresis undergoing unilateral modified Harada-lto procedures during the five-year period 1988-1993 was performed. Results: Six patients fulfilled the inclusion criteria. Superior oblique paresis was congenital in one case, secondary to trauma in two cases and idiopathic acquired in three cases. There were four males and two females aged from 25 to 63 years and all but one had previous surgery. The mean pre-operative excyclotorsion was approximately 10 degrees (range 8-14 degrees). Mean post-operative excyclotorsion was 3 degrees (range 2 degrees incyclotorsion -10 degrees excyclotorsion). Conclusion: The unilateral modified Harada-lto procedure is an effective surgical treatment of excyclotorsion resulting from superior oblique paresis and may improve sensory and motor fusion.  相似文献   
44.
Weight loss following vertical banded gastroplasty (VBG) is well established. Herein the effect of weight loss on sexuality was examined. Twenty-seven females and seven males (mean age 39 years) underwent VBG and returned completed questionnaires regarding preoperative and postoperative sexuality. There was a mean interval follow-up of 33 months, with a mean weight loss of 48.6 kg. In general, there was an overall increase in frequency, quality, and enjoyment of sex. Similarly, an improvement in body image, an increase in initiating sexual intercourse, and an increase in the number of sexual partners was found. A small number of patients developed psychosocial problems that limited sexual enjoyment. In conclusion, weight loss after VBG improves sexual life, though not uniformly, as new sexual problems can occur. Decreased sexual inhibition, increased sexual enjoyment and frequency, and increased frequency of orgasm characterizes many of the changes occurring after VBG with resultant weight loss. To help provide a holistic approach to the care of morbidly obese patients after VBG, the potential alterations in their sexual lives should be considered.  相似文献   
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PURPOSE: This phase III randomized trial evaluated survival as well as neurologic and neurocognitive function in patients with brain metastases from solid tumors receiving whole-brain radiation therapy (WBRT) with or without motexafin gadolinium (MGd). PATIENTS AND METHODS: Patients were randomly assigned to 30 Gy of WBRT +/- 5 mg/kg/d MGd. Survival and time to neurologic progression determined by a blinded events review committee (ERC) were coprimary end points. Standardized investigator neurologic assessment and neurocognitive testing were evaluated. RESULTS: Four hundred one (251 non-small-cell lung cancer) patients were enrolled. There was no significant difference by treatment arm in survival (median, 5.2 months for MGd v 4.9 months for WBRT; P =.48) or time to neurologic progression (median, 9.5 months for MGd v 8.3 months for WBRT; P =.95). Treatment with MGd improved time to neurologic progression in patients with lung cancer (median, not reached for MGd v 7.4 months for WBRT; P =.048, unadjusted). By investigator, MGd improved time to neurologic progression in all patients (median, 4.3 months for MGd v 3.8 months for WBRT; P =.018) and in lung cancer patients (median, 5.5 months for MGd v 3.7 months for WBRT; P =.025). MGd improved neurocognitive function in lung cancer patients. CONCLUSION: The overall results did not demonstrate significant differences by treatment arm for survival and ERC time to neurologic progression. Investigator neurologic assessments demonstrated an MGd treatment benefit in all patients. In lung cancer patients, ERC- and investigator-determined time to neurologic progression demonstrated an MGd treatment benefit. MGd may improve time to neurologic and neurocognitive progression in lung cancer.  相似文献   
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Purpose: To determine the impact of whole pelvic irradiation on the risk of PSA failure in prostate cancer patients, at high predicted risk for lymph node involvement, receiving definitive radiotherapy.

Materials and Methods: Between October 1987 and December 1995, 506 patients with clinically localized prostate cancer were treated with definitive radiotherapy at UCSF and affiliated institutions. Treatment consisted of 4-field whole pelvic irradiation followed by a prostate-only boost, or prostate-only treatment (median follow-up was 35 months and 30 months, respectively). PSA failure was defined as: 1. a PSA value ≥ 1 ng/ml; or 2. a PSA value that rose ≥ 0.5 ng/ml in ≤ 1 year posttreatment on two consecutive measurements, with the first rise defined as the time of failure. The calculated risk of lymph node positivity (%rLN+) was defined as (iPSA) + 10(GS-6), and high risk was defined as %rLN+ ≥ 15%. Univariate and multivariate analyses were performed.

Results: A total of 201 high-risk patients were identified. High-risk patients who received whole pelvic irradiation had significantly improved freedom from PSA failure compared to those who received prostate-only treatment (median PFS = 34.3 months vs. 21.0 months; p = 0.0001). Potential confounding variables, including initial PSA, Gleason score, T stage, radiation dose, year of treatment, use of three-dimensional (3D) conformal techniques, and use of hormone therapy, did not account for the observed difference in time to PSA failure. Multivariate analysis revealed type of radiation treatment to be the most significant independent predictor of outcome.

Conclusion: Whole pelvic radiotherapy significantly improves the PSA failure-free survival in patients with a high calculated risk of lymph node positivity.  相似文献   

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Neuroimaging probes of brain regions implicated in emotion represent an important research strategy for understanding emotional dysfunction in schizophrenia. Anterior limbic structures, such as the ventral striatum and the amygdala, have been implicated in the pathophysiology of schizophrenia and the generation of emotional responses, although few studies to date have used emotion probes to target these areas in schizophrenia. With this goal in mind, emotionally salient visual images were used in a simple, nondemanding task. In all, 13 medicated, schizophrenic patients, five unmedicated patients, and 10 healthy volunteers viewed complex visual pictures and a nonsalient, blank screen while regional cerebral blood flow was measured with the [O-15] water technique. Pictures consisted of real world scenes with aversive, positive, and nonaversive content. Eye movements were recorded simultaneous with scan acquisition. Positron emission tomography images were analyzed for baseline, tonic activity, in addition to phasic changes ('activation') to salient stimuli. Lateral eye movement measures and on-line ratings showed good behavioral compliance with the task. Patients with schizophrenia showed impaired neural responses to salient stimuli in the right ventral striatum (VS), and they exhibited elevated tonic activity levels in the right VS and bilateral amygdala, inversely correlated with overall symptom severity. The patients also showed reduced modulation of visual cortex by salient stimuli. The results show that patients with schizophrenia exhibit impaired neural responses to emotionally salient stimuli in the VS, supporting a role for this structure in the pathophysiology of the illness. Reduced modulation of visual cortex by emotionally salient stimuli also suggests a failure to organize cerebral activity at a global level.  相似文献   
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