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101.
Three groups of judges representing clinical, political, and laypersons' perspectives were given the task of prioritizing patients for subsidized psychotherapy within the Swedish health care system. The authors documented the judges' decision-making processes in think-aloud protocols and analyzed them qualitatively, focusing on the conflict between the urgency of a case and its suitability for treatment. In an earlier statistical analysis of the same material, clinicians had seemed to pay more attention to suitability criteria, whereas health care officials and laypersons prioritized based on urgency. The qualitative findings confirmed the centrality of this conflict and contributed to a deeper understanding of decision makers' ways of coping with it. Their conceptions of suitability and urgency were also elucidated by analysis of the think-aloud protocols.  相似文献   
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PURPOSE: To investigate the importance of CT-defined total tumor volume (TTV) on overall survival (OS) in patients with unresectable or medically inoperable non-small-cell lung carcinoma (NSCLC). METHODS AND MATERIALS: Between 1991 and 1998, 150 evaluable patients with Stage I-IIIB NSCLC were treated with three-dimensionally planned conformal radiotherapy and curative intent at Duke University Medical Center. On the treatment-planning CT, the primary tumor and nodal volumes were identified and subsequently combined to form the TTV. The TTV was compared with the stage and outcome with respect to OS, local progression-free survival, and distant failure-free survival using the Kruskall-Wallis analysis of variance and Kaplan-Meier actuarial method. To account for the potentially confounding effects of therapeutic and patient-specific covariates on survival, the Cox proportional hazard regression model was used. RESULTS: The TTVs in patients with Stage I disease (median 19 cm3) were smaller than in patients with Stage II (median 80 cm3) or Stage III (median 97 cm3; p <0.001) disease. The Stage II TTVs were not significantly different from those of Stage III (post-hoc test according to Bonferroni). Prolonged OS was independently associated with a small TTV (<80 vs. >80 cm3 [median]; p = 0.01), young age (<60 vs. > or =60 years; p = 0.03), high Karnofsky performance status (< o r =70 vs. >70; p = 0.04), and female gender (p = 0.04). Both stage (p = 0.7) and T stage (p = 0.06) were of less importance for OS than was the TTV, according to multivariate modeling. Increased local progression-free survival (p = 0.001) and distant failure-free survival (p = 0.03) were independently associated with a small TTV (i.e., <80 cm3). The results were unchanged if the TTV was analyzed as a continuous variable. CONCLUSION: A strong independent association between a small CT-defined TTV and prolonged survival in patients with NSCLC selected for curative/definitive RT was found. Future therapeutic studies in NSCLC should consider stratifying/adjusting for differences in TTV to avoid confounding effects on survival from variations in the TTV at baseline.  相似文献   
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BACKGROUND: A majority of patients with pancreatic cancer have obstructive jaundice and diabetes with skeletal muscle insulin resistance. Surgery for these patients is associated with significant morbidity. Uncoupling protein 2 (UCP2) has been proposed to regulate energy expenditure and promote liver vulnerability. The effects of obstructive jaundice on muscle glucose metabolism and expression of UCP2 in liver and muscle are unknown. METHODS: Rats were operated with bile duct ligation (BDL). After 7 days, UCP2 mRNA levels were determined in liver and muscle. Simultaneously, insulin-stimulated glucose transport and glycogen synthesis in skeletal muscle were analyzed in vitro. RESULTS: The jaundiced rats lost more weight than pair-fed controls. UCP2 mRNA levels were increased 5-fold in liver but not in muscle in jaundiced rats compared to pair-fed controls. The jaundiced rats were hypoglycemic and hypoinsulinemic but demonstrated intact or enhanced insulin action on skeletal muscle glucose transport and glycogen synthesis in vitro. Muscle glycogen content was increased in the jaundiced rats. CONCLUSIONS: Experimental obstructive jaundice in the rat is associated with increased liver expression of UCP2, rapid weight loss, and intact insulin action on skeletal muscle glucose metabolism. Obstructive jaundice, by upregulated liver UCP2, may contribute to the cachexia and high surgical morbidity observed in these patients, but not to skeletal muscle insulin resistance in pancreatic cancer patients.  相似文献   
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OBJECTIVE: To compare the diagnostic accuracy of contrast medium enhanced spiral computed tomography of the pulmonary arteries (s-CTPA) and a latex agglutination D-dimer assay in patients with suspected acute pulmonary embolism (PE) by using pulmonary arteriography (PA) and clinical follow-up as reference method. DESIGN: Ninety hemodynamically stable patients with symptoms of acute pulmonary embolism were prospectively evaluated with s-CTPA and pulmonary arteriography (PA) within 24 h from admission. Plasma D-dimer levels on admittance were analyzed using a rapid latex agglutination D-dimer assay. The outcome of D-dimer concentrations in plasma below 0.25 and 0.5 mg/l was studied. RESULTS: All PA and s-CTPA investigations were regarded as of acceptable diagnostic quality in a consensus reading. Thirty-three patients had a positive PA (37%). Three patients had false negative and two patients had false positive s-CTPA findings. s-CTPA had 91% sensitivity, 96% specificity, 94% positive predictive value (PPV) and 95% negative predictive value (NPV). The sensitivity and specificity for D-dimer below 0.5 mg/l were 79 and 88%, respectively. The PPV and NPV were 81 and 87%. If a cut-off level of 0.25 mg/l was used the corresponding figures were 91, 65, 63 and 92%. CONCLUSION: s-CTPA has a higher sensitivity and specificity than latex agglutination D-dimer. A cut-off level of 0.25 mg/l can be used as screening method, but s-CTPA must be performed to exclude false positive cases.  相似文献   
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PURPOSE: The purpose of this study was to evaluate gender differences in the relationship between night driving self-restriction and vision function in an older population. METHODS: Night driving self-restriction patterns (assessed by questionnaire) were examined cross-sectionally in relation to age, gender, health and cognitive status, depression, and vision function in a sample of 900 elders (mean age, 76 years) living in Marin County, California. RESULTS: Of the total sample, 91% of men and 77% of women were current drivers. The mean age of the drivers was 73.3 years (range, 58-96 years). Among current drivers, women had slightly better vision function than men on most measures (low-contrast acuity, contrast sensitivity, low-contrast acuity in glare, low-contrast, low-luminance acuity, and glare recovery) but were twice as likely as men to restrict their driving to daytime. Men showed significant associations with avoidance of night driving on four spatial vision measures (high- and low-contrast acuity, low-contrast, low-luminance acuity, and contrast sensitivity). For women, in addition to these measures, a significant association was seen for low-contrast acuity in glare. Neither men nor women showed significant associations between driving restriction and performance on the other vision measures examined (glare recovery time, attentional field integrity, or stereopsis). The vision measures most predictive of self-restriction were contrast sensitivity for men and low-contrast acuity in glare for women. CONCLUSIONS: Including both cessation and self-restriction, men over age 85 years are 6.6 times more likely than women to be driving at night. For both genders, vision plays a significant role in the self-restriction decision. A higher percentage of men than women continue to drive at night with poor vision. Men's night-driving cessation was associated with contrast sensitivity and depression, whereas women's night-driving cessation was associated with low-contrast acuity in glare as well as age.  相似文献   
109.
Objective: To identify health care issues important to reduce the perinatal mortality rate (PMR) in Ukraine. Study Design: Perinatal deaths in the Donetsk region (Ukraine) in 1997–1998 were compared with those in Denmark in 1996 by using the Nordic–Baltic classification for perinatal deaths. Clinical guidelines, use of technology and rates of interventions in the two regions were described. Results: A two-fold increase in PMR was found in Ukraine compared to Denmark, mainly explained by higher rates of antenatal deaths of growth restricted fetuses, intrapartum deaths, and neonatal deaths due to asphyxia. Vacuum extraction is rarely used in Ukraine. The clinical guidelines for care differ significantly between the two regions. Conclusion: Appropriate use of technology and implementation of evidence-based guidelines should be a matter of high priority in the Donetsk region, Ukraine.  相似文献   
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