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The effectiveness of an antiarrhythmic drug is judged by the degree of ventricular arrhythmia (VA) suppression. We evaluated the relationship between the degree of VA suppression and survival in a dose-adjusted trial of 110 symptomatic patients treated with amiodarone. Cohorts had left-ventricular ejection fraction (LVEF) of 41 plus minus 18%, ventricular premature contractions (VPCs) of 445 plus minus 571 h, couplets (C) of 733 plus minus 1498 24 h and nonsustained (N) ventricular tachycardia (VT) of 65 plus minus 217 24 h; these conditions were followed for 15 plus minus 11.5 months. Amiodarone was initiated with an oral loading of 670 plus minus 111.7 mg per day for 10 days and continued on maintenance of 274.9 plus minus 102 mg per day. Survival rates of responders and nonresponders with VPCs <70%, 70--89%, greater-than-or-equal90%; C greater-than-or-equal 90%; NVT (100%); and the response to all 3 criteria (suppresion of VPCs greater-than-or-equal70%, C greater-than-or-equal 90% and complete abolition of NVT) were not statistically significant. Survival rates as a function of LVEF <40% (51 patients) or greater-than-or-equal40% (59 patients), as well as responders or nonresponders to all three criteria, were not significant (p = NS). We conclude that, in patients treated with low-dose amiodarone, the degree of VA suppression of PVCs, C and NVT does not predict survival; the survival of patients with LVEF <40% improved irrespective of VA suppression; and criteria for VA suppression should be reassessed at lower levels of suppression for the improvement of the drug risk:benefit ratio. More improvement is not necessarily better.  相似文献   
54.
PURPOSE: To describe a randomized trial of a cognitive behavioral intervention on reducing symptom severity among patients diagnosed with solid tumors and undergoing a first course of chemotherapy and to determine whether the intervention had an additive or interactive effect on symptom severity in the presence of supportive care medications. PATIENTS AND METHODS: Patients (N = 237) were accrued from comprehensive and community cancer centers, interviewed, and randomly assigned to either the experimental intervention (n = 118) or conventional care (n = 119). A symptom severity index, based on summed severity scores across 15 symptoms, was the primary outcome. Each patient's site of cancer, stage at diagnosis, chemotherapy protocols, and use of supportive medications were learned from medical records. RESULTS: Groups were equivalent at baseline, and attrition by characteristics by group was not different. The proportion of patients not receiving chemotherapy at 10 and 20 weeks did not differ by group. At the 10- and 20-week observations, there was a significant interaction between the experimental group and baseline symptom severity. Patients in the experimental group who entered the trial with higher symptom severity reported significantly lower severity at 10 and 20 weeks. Controlling for chemotherapy treatment status at follow-up and supportive care medications did not alter the effect of the experimental intervention. CONCLUSION: Compared with conventional care alone, the experimental intervention was effective among patients who entered the trial with higher levels of symptom severity. Age, sex, site or stage of cancer, and supportive medications did not modify the effect of this cognitive behavioral intervention on symptom severity.  相似文献   
55.
Genomic sequences of the human polyomaviruses, JC virus (JCV) and BK virus (BKV), and simian virus 40 (SV40) have been reported from several types of human brain tumors, but there have been no population-based seroepidemiologic studies to evaluate the association between polyomavirus infection and brain tumors. We conducted a case-control study, nested within a prospective cohort, to investigate the association between antibodies to JCV, BKV, and SV40, as measured in serum collected 1-22 years before diagnosis and incident primary malignant brain tumors. Brain tumor cases (n = 44) and age-, gender-, and race-matched controls (n = 88) were identified from participants of two specimen banks in Washington County, Maryland. IgG antibodies to the capsid proteins of JCV and BKV were assessed using ELISAs. SV40-neutralizing antibodies were measured using plaque neutralization assays. Similar to the general population, the prevalence of JCV and BKV infection was high in our study population (77 and 85%, respectively). Antibodies to SV40 were less prevalent (11%). The odds ratio for subsequent brain tumor development was 1.46 [95% confidence interval (CI), 0.61-3.5] for JCV, 0.66 for BKV (95% CI, 0.22-1.95), and 1.00 for SV40 (95% CI, 0.30-3.32). Given the high prevalence of JCV and BKV infections and the millions who were potentially exposed to SV40 through contaminated polio vaccines, future studies should attempt to replicate these findings.  相似文献   
56.
Experimental and human epidemiologic data suggest a protective rolefor vitamin D in large bowel cancer. To investigate this association, weconducted a nested case-control study within a Finnish clinical trial cohort.Cases (n = 146) were participants diagnosed with primary adenocarcinoma ofthe large bowel. Controls were matched (2:1) to cases on age, date ofbaseline blood draw, and study clinic. Prediagnostic serum levels of thevitamin D metabolites, 25-hydroxyvitamin D (25-OH D), and1,25-dihydroxyvitamin D (1,25-DIOHD) were used as primary exposure measures.The baseline geometric-mean serum level of 25-OH D was 11.6 percent lower incases than in controls (12.2 cf 13.8 ug/l, P = 0.01) while serum levels of1,25-DIOH D did not differ by case-control status. No association was seenbetween serum levels of 1,25-DIOH D and large bowel cancer risk. However, theestimated relative risk (RR) of large bowel cancer decreased with increasinglevel of serum 25-OH D and the associa tion was more pronounced for rectalcancer (55 cases; RR by quartile = 1.00, 0.93, 0.77, 0.37; trend P = 0.06).Neither exclusion of early cases nor multivariate adjustment for potentialconfounders materially altered these estimates. There was no evidence ofeffect modification by level of 1,25-dihydroxyvitamin D or with other knownrisk-factors for large bowel cancer.  相似文献   
57.
Objective: To establish tissue inhibitor of metalloproteinase-1 (TIMP-1) concentrations in peritoneal fluid (PF) and sera of women with endometriosis and compare them to disease-free controls.

Design: Prospective randomized study.

Setting: Academic medical center.

Patient(s): Women with laparoscopically documented endometriosis and disease-free women of reproductive age.

Intervention(s): Peritoneal fluid and sera were collected, and some women received gonadotropin-releasing hormone agonist (GnRH-a) therapy for endometriosis.

Main Outcome Measure(s): Peritoneal fluid and sera TIMP-1 concentrations were measured with a specific RIA.

Result(s): The TIMP-1 concentrations were significantly lower in PF and sera of women with endometriosis compared with disease-free women. The GnRH-a therapy restored serum TIMP-1 concentrations.

Conclusion(s): Aberrant expression and localization of TIMP-1 may derange the proteolytic milieu of the peritoneal cavity and contribute to the etiology and underlying physiologic sequelae associated with endometriosis. Measurement of TIMP-1 in serum may aid in diagnosing endometriosis and assist with monitoring treatment efficacy in women with this disease.  相似文献   

58.
The impact of goal attainment in a dietary change program to increase fruit, 100% juice, and vegetable consumption was assessed among fourth-grade students. At each session, the students were given goals related to increasing fruit, juice, and vegetable consumption. Baseline consumption and postconsumption were assessed with up to 4 days of computerized dietary recalls. Analyses included regression models predicting postconsumption from the numbers of fruit-juice goals, vegetable goals, or total number of general goals attained, respectively. For students with low baseline fruit-juice preferences, attaining more fruit-juice goals resulted in increased post-fruit-juice consumption. Among those with low baseline vegetable consumption, attaining one vegetable goal was related to higher post-vegetable consumption. For boys and those with high baseline fruit, juice, and vegetable consumption, attaining three general goals was related to increased fruit, juice, and vegetable intake. The results show that goal attainment was somewhat effective in promoting dietary change among children.  相似文献   
59.
PURPOSE: Obese women and women who gain weight after a breast cancer diagnosis are at a greater risk for breast cancer recurrence and death compared with lean women and women who do not gain weight after diagnosis. In this population-based study, we assessed weight and body fat changes from during the first year of diagnosis to during the third year after diagnosis, and whether any changes in weight and body fat varied by demographic, prognostic, and lifestyle factors in 514 women with incident Stage 0-IIIA breast cancer. METHODS: Patients were participants in the Health, Eating, Activity, and Lifestyle (HEAL) study. Weight and body fat (via dual-energy x-ray absorptiometry scans) were measured during the baseline visit and 2 years later at a follow-up visit. Analysis of covariance methods were used to obtain mean weight and body fat changes adjusted for potential cofounders. RESULTS: Women increased their weight and percent body fat by 1.7 +/- 4.7 kg and 2.1% +/- 3.9%, respectively, from during their first year of diagnosis to during their third year of diagnosis. A total of 68% and 74% of patients gained weight and body fat, respectively. Greater increases in weight were observed among women diagnosed with a higher disease stage, younger age, being postmenopausal, and women who decreased their physical activity from diagnosis to up to 3 years after diagnosis (P for trend < .05). CONCLUSION: Weight and body fat increased in the postdiagnosis period. Future research should focus on the effect of physical activity on weight and fat loss and breast cancer prognosis.  相似文献   
60.
Simian virus 40 (SV40) genome sequences have been detected in human non-Hodgkin lymphoma (NHL) tissues, and past infection with SV40 may be a risk factor for NHL. We conducted a population-based nested case-control study to investigate the association between serum antibodies to SV40 and incident NHL. Two research serum banks were established in Washington County, MD, with >45,000 volunteers contributing blood samples collected in 1974 and 1989. Incident cases of NHL diagnosed through 2002 (n = 170) were identified among participants by linkage to population-based cancer registries. Two controls were matched to each case (n = 340) on age, sex, and date of blood draw. Circulating immunoglobulin G antibodies to SV40 were measured using virus-like particle (VLP) ELISA. Positive samples were tested for cross-reactivity with JC virus (JCV) and BK virus (BKV) through competitive inhibition assays. Associations between SV40 antibody seropositivity and NHL were estimated using conditional logistic regression. Whereas SV40 antibodies were detected by VLP ELISA in 15% of cases and 10% of controls [matched odds ratio (OR), 1.97; 95% confidence interval (95% CI), 1.03-3.76], the SV40 reactivity of 85% of the SV40 antibody-positive sera was decreased by adsorption with BKV and/or JCV VLPs. Antibodies specific for SV40 (not cross-reactive) were identified in only 1.8% of cases and 1.6% of controls (OR, 1.51; 95% CI, 0.41-5.52). Our findings suggest that past infection with SV40 is not associated with an increased risk of developing NHL.  相似文献   
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