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71.
The authors studied the impact of edge enhancement and gray scale polarity reversal on the detection of subtle lung cancers. Three experienced readers reviewed 46 biopsy-proved subtle lung cancers and 46 normal controls on chest radiographs that had been digitized into a 1,024 X 1,536-pixel matrix 8 bits deep. Receiver-operating characteristics (ROC) analysis of 1,656 pooled observations indicated that performance was best with the unmodified images (ROC area = 0.83), degraded by moderate enhancement of medium frequencies (ROC area = 0.80), and markedly impaired by severe enhancement of low frequencies (ROC area = 0.69). Gray scale polarity reversal further degraded performance (unenhanced ROC area = 0.74; moderately enhanced ROC area = 0.76; severely enhanced ROC area = 0.76). The authors conclude that edge enhancement and gray scale polarity reversal can impair the detectability of subtle lung cancers on digitized radiographs of medium resolution.  相似文献   
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Objective

The purpose of this study is to compare the effectiveness of a combined 12-week home-based exercise (EX)/cognitive behavioral therapy (CBT) program (n=18) with CBT alone (n=19), EX alone (n=20), and with usual care (UC, n=17) in stable New York Heart Association Class II to III heart failure (HF) patients diagnosed with depression.

Methods

Depressive symptom severity [Hamilton Rating Scale for Depression (HAM-D)], physical function [6-min walk test (6MWT)], and health-related quality of life (HRQOL) (Minnesota Living with Heart Failure Questionnaire) were evaluated at baseline (T1), after the 12-week intervention/control (T2), and following a 3-month telephone follow-up (T3). A repeated measures analysis of variance was used to determine group differences. Depression severity was dichotomized as minor (HAM-D, 11-14) and moderate-to-major depression (HAM-D, ≥15), and group intervention and control responses were also evaluated on that basis.

Results

The greatest reduction in HAM-D scores over time occurred in the EX/CBT group (−10.4) followed by CBT (−9.6), EX (−7.3), and UC (−6.2), but none were statistically significant. The combined group showed a significant increase in 6-min walk distance at 24 weeks (F=13.5, P<.001). Among all groups with moderate-to-major depression, only those in CBT/EX had sustained lower HAM-D scores at 12 and 24 weeks, 6MWT distances were significantly greater at 12 (P=.018) and 24 (P=.013) weeks, and the greatest improvement in HRQOL also occurred.

Conclusions

Interventions designed to improve both physical and psychological symptoms may provide the best method for optimizing functioning and enhancing HRQOL in patients with HF.  相似文献   
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OBJECTIVE: To describe psychological reactions among family members of patients receiving an implantable cardioverter/defibrillator (ICD) during the first 9 months after implantation. METHODS: Eighty-two family members (age 56+/-12 years, 74 percent female, 79 percent married, 88 percent Caucasian) of ICD patients completed questionnaires regarding their mood (Profile of Mood State), cognitive illness appraisals (Meaning of Illness Questionnaire) and coping strategies (Jalowiec Coping Scale) prior to ICD implantation, and as well as 1 and 9 months postoperatively. RESULTS: Total mood disturbance score (TMD), threat appraisal, and emotion- and problem-focused coping were highest prior to ICD implantation, and decreased during the first postoperative month showing stable values thereafter. There was no change in challenge appraisal. Multiple regression analysis found that the use of psychotropic drugs (anxiolytics, sedatives; Beta = .25), emotion-focused coping (Beta = .37), and challenge appraisal (Beta =-.21) at 1 month accounted for 26 percent of variance in TMD at 9 mon ths. CONCLUSION: A spouse's ICD implantation is a major stressful event for family members leading to a diminished mood state prior ICD implantation. Reduction in emotion-focused coping and the use of challenge appraisal may improve mood state in family members of ICD patients during early follow-up.  相似文献   
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A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
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