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PURPOSE This study was designed to determine whether oral retinol palmitate (vitamin A) can reduce the symptoms of radiation proctopathy.METHODS A randomized, double-blind trial comparing retinol palmitate (10,000 IU by mouth for 90 days) to placebo was conducted. Eligible patients were more than six months postpelvic radiotherapy and had significant symptoms as measured with the Radiation Proctopathy System Assessments Scale. Nineteen patients were randomized in total: ten to retinol palmitate and nine to placebo. The Radiation Proctopathy System Assessments Scale scores before and every 30 days for 90 days were measured. Five placebo nonresponders were crossed over to the retinol palmitate for another 90 days. Response was defined as a reduction in two or more symptoms by at least two Radiation Proctopathy System Assessments Scale points.RESULTS Seven of ten retinol palmitate patients responded, whereas two of nine responded to placebo (P = 0.057). Mean pre-post-treatment change in Radiation Proctopathy System Assessments Scale ( Radiation Proctopathy System Assessments Scale) in the retinol palmitate group was 11 ± 5, whereas Radiation Proctopathy System Assessments Scale in the placebo group was 2.5 ± 3.6 (P = 0.013, Mann-Whitney U test). Additionally, all five placebo nonresponders who were crossed over to treatment with retinal palmitate responded to treatment.CONCLUSIONS In our trial, retinol palmitate significantly reduced rectal symptoms of radiation proctopathy, perhaps because of wound-healing effects. The current results can serve as the foundation for future trials examining retinol palmitate in the multi-institutional setting.Supported in part by a private grant from Arthur C. Nielsen, Jr.  相似文献   
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INTRODUCTION: Anxiety disorders in adults involve aberrant processing of emotional information that is hypothesized to reflect perturbations in the amygdala. This study examines the relationship between face-emotion recognition and anxiety in a sample of children and adolescents participating in a brain-imaging study of amygdala structure and function. METHODS: This study recruited 15 children and adolescents with ongoing anxiety disorders and 11 psychiatrically healthy comparisons group-matched on age, gender, and IQ. Face-emotion recognition was assessed using the Diagnostic Analysis of Nonverbal Accuracy Scale (DANVA). RESULTS: Children and adolescents with anxiety disorders exhibited significantly poorer performance on the face-emotion recognition task compared to healthy controls (z = 2.2; p < 0.05). This difference was found only for expressions posed by adults but not children. Discussion: Reduced accuracy on a face-emotion recognition test is consistent with perturbed amygdala function in pediatric anxiety disorders. CONCLUSION: As this study was conducted in a sample undergoing a neuroimaging investigation of amygdala integrity, future analyses will examine associations among amygdala function, clinical anxiety, and face-recognition abilities.  相似文献   
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OBJECTIVE: To examine the relation between baseline measurements of thyroid function and response to selective serotonin reuptake inhibitors (SSRIs) and to consider the effect of these antidepressants on thyroid hormone levels. METHODS: Nineteen subjects with major depression, but without a history of thyroid treatment or lithium treatment, were treated openly with either sertraline or fluoxetine in a university- affiliated tertiary care hospital. Hamilton Depression Rating Scale (Ham-D) scores were measured before and after treatment. Clinical Global Impressions (CGI) scores were measured at study end. Thyroid data, consisting of values for thyroid-stimulating hormone (TSH), triiodothyronine (T(3), measured by radioimmunoassay [RIA]), thyroxine (T(4), measured by RIA) and free T(4), were collected before and after treatment. Complete thyroid data were available for 17 subjects. Data were collected during 1997-1999. RESULTS: Baseline TSH correlated strongly with response to treatment as measured by change in Ham-D scores (r = 0.64, p = 0.003). Low TSH values correlated with greater improvement in depressive symptoms. Thyroid hormone levels decreased with treatment, but these decreases did not correlate with clinical improvement. CONCLUSION: Baseline thyroid function, as measured by serum TSH, may predict a patient's response to antidepressant treatment with SSRIs. Optimal thyroid function, beyond simply being within the normal laboratory values, may be necessary for an optimal response to antidepressants.  相似文献   
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Although there has been considerable interest in racial differences in family caregiving for persons with dementia, most research to date has either ignored racial diversity or based conclusions on small numbers of caregivers drawn primarily from single site studies. The current study utilized participants from four sites of the REACH (Resources for Enhancing Alzheimer's Caregiver Health) multi-site study to compare well-being, appraisal, and religious coping by race. African-American (n = 295) and Caucasian (n = 425) dementia caregivers from four cities (Birmingham, Memphis, Boston, and Philadelphia) were compared in their demographics, care recipient characteristics, mental and physical health, and psychosocial coping resources including appraisal and religious coping. African-American caregivers reported lower anxiety, better well-being, less use of psychotropic medications, more benign appraisals of stress and perceived benefits of caregiving, and greater religious coping and participation, than Caucasian caregivers. Self-rated health did not differ by race, but African-American caregivers reported more unhealthy behaviors than Caucasian caregivers. Some results were specific to site, possibly due to differences in recruitment strategies, inclusion/exclusion criteria, and regional differences. Adjustment for covariates, including caregiver relationship to the care recipient, gender, age, socioeconomic status, and care recipient behavioral problems, altered few of these differences. Results are discussed in terms of their relevance to psychosocial intervention programs for ethnically diverse caregivers.  相似文献   
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A 22-month-old boy, who regularly consumed the oral dietary supplement, quercetin, was suspected erroneously of having a catecholamine-producing tumor, based on elevated serum and urine levels of the dopamine metabolite, homovanillic acid (HVA). Subsequent studies of healthy adult volunteers showed that significant elevations in plasma HVA are a consequence of quercetin ingestion.  相似文献   
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Park TW  Winawer J  Wallman J 《Vision research》2003,43(14):1519-1531
Young animals compensate for defocus imposed by positive or negative spectacle lenses by adjusting the elongation rate of their vitreous chambers, thus matching the length of the eye with the focal length of the eye's optics combined with the spectacle lenses. The ability to compensate for either negative or positive lenses could rely on the ability to distinguish between myopic and hyperopic blur, or it could rely on the fact that positive lenses would bring nearby objects into focus, thereby reducing the amount of blur, whereas negative lenses would not. This study asks whether eyes emmetropize using the magnitude of blur or the sign of blur as a directional cue. We fitted chick eyes with positive lenses while imposing a substantial amount of blur, either (a) by having them wear lenses only when restrained in the center of a cylinder, the walls of which were beyond their far-point or (b) by having them wear mild diffusers over positive lenses. We found good refractive compensation in both situations in a large number of birds. Furthermore, we found that mild diffusers worn on top of positive lenses differentially affected the two ocular components of refractive compensation: there was less choroidal thickening, but more inhibition of ocular elongation, compared to wearing positive lenses alone. These findings argue both that the eye can discern the sign of the blur and that choroidal and ocular-elongation components of the refractive compensation do not respond identically to visual inputs.  相似文献   
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