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161.
OBJECTIVE: The purpose of this study was to assess the computed tomography (CT) features of the pericardial "sleeve" recess of the right inferior pulmonary vein misinterpreted as adenopathy. METHOD: Six patients with fluid in the pericardial sleeve recess mistaken for adenopathy were retrospectively identified. The following CT features were assessed: location of fluid in relation to the vein, size, shape, attenuation, and mass effect on the inferior pulmonary vein. RESULTS: The most common presentation was fluid inferior and posterior to the vein. The anterior and posterior components are typically spindle shaped, whereas the superior and inferior components are ovoid. The attenuation values of the fluid ranged from 2-32 H (mean = 13 H). None of the fluid collections exerted mass effect on the right inferior pulmonary vein. CONCLUSION: Although fluid in the right pulmonary venous sleeve pericardial recess can mimic adenopathy, this accumulation has a characteristic appearance, and knowledge of this normal variant is useful in preventing misinterpretation.  相似文献   
162.
The clinical significance and prevalence of Mycobacterium avium and Mycobacterium intracellulare were analyzed in a cohort of 7,472 patients who, from 1999 to 2003, sought care at the University of Texas M.D. Anderson Cancer Center, Houston, and had cultures performed for mycobacteria. Patients were stratified for age, sex, and underlying diseases, and bacteria were identified by 16S rRNA gene sequencing. M. avium was isolated in 62 (0.83%) of 7,472 patients and M. intracellulare in 65 (0.87%). Clinically, only 10 of the 62 (16.2%) patients with M. avium had probable to definite evidence of infection, whereas the majority (83.8%) had weak evidence of infection. Sex and age did not affect the isolation or infection of M. avium. Hematological tumors predisposed to M. avium colonization but not infection. In contrast, 41 of the 65 (63.1%) patients with M. intracellulare had probable to definite infection, a level much higher than those with M. avium (P < 0.001). M. intracellulare was more prevalent in women (1.33% of 3,311) than in men (0.50% of 4,161) (P < 0.001), and underlying diseases had no effect in women. Men with lung cancer had a higher prevalence (1.37%) than men without (0.34%) (4.0-fold; P < 0.001), but it was similar to that in women. A marked age trend for the isolation of M. intracellulare among women was noted: 0.27% (1-fold) for ages of <50 years, 0.85% (3.1-fold) for ages 50 to 59 years, 1.50% (5.6-fold) for ages 60 to 69 years, and 3.74% (13.9-fold) for ages >/=70 years (trend, P < 0.001). The combined rate for women >/=50 was 1.86% (95% confidence interval [1.30 to 2.42%]) (6.9-fold). Together, these results suggest that, among non-AIDS patients, M. intracellulare is more pathogenic and tends to infect women increasingly beyond menopause (age >/=50 years) regardless of underlying disease. The prevalence rate of 1.86% in postmenopausal women suggests the need to further investigate the public health significance of M. intracellulare.  相似文献   
163.
164.
The General Health Questionnaire (GHQ-12) detects non severe psychiatric illnesses. Although commonly treated as a general index, the definition of its factorial structure is cause for debate. This study aimed to test this structure comparing three models: two frequently cited in the literature (one- and bi- factorial) and a third, also one-factor, which controls response bias due to the negative wording of items. A total of 1,180 people participated (300 undergraduates, 311 military policemen, 274 elementary school teachers and 295 members of the general population) answering the GHQ-12 and demographic questions. Confirmatory factor analyses showed that the one-factor structure, controlling by the wording effect, gathered the best fit indexes, except among the military. This structure showed greater than 0.80 reliability in all groups. It was concluded that the one-factor model of the GHQ-12 is more appropriate, however, future studies are required with people with different occupations and levels of mental health.  相似文献   
165.
A lack of good quality evidence on the effect of alternative social policies in low- and middle-income countries has been recently underlined and the value of randomized trials increasingly advocated. However, it is also acknowledged that randomization is not always feasible or politically acceptable. Analyses using longitudinal data series before and after an intervention can also deliver robust results and such data are often reasonably easy to access. Using the example of evaluating the impact on utilization of a change in health financing policy, this article explains how studies in the literature have often failed to address the possible biases that can arise in a simple analysis of routine longitudinal data. It then describes two possible statistical approaches to estimate impact in a more reliable manner and illustrates in detail the more simple method. Advantages and limitations of this quasi-experimental approach to evaluating the impact of health policies are discussed.  相似文献   
166.
Recent policy recommendations have called for increased research efforts to inform the design of cost-effective interventions to address the shortage of health workers in rural areas. This paper takes forward the recent use of Discrete Choice Experiments to assess the effects of potential incentives to attract nurses to rural areas. The analysis relies on data collected in South Africa between August and November 2008. Effectiveness measures derived from Discrete Choice Experiments are combined in a Markov model to derive the long-term effects of policies, and costs are evaluated with secondary data. Measures involving the selection of more nursing students who are more likely to accept positions in rural areas are shown to be the most cost-effective interventions. If such policies could not be implemented, the next best options are to offer preferential access to specialist training to nurses willing to work in rural areas.  相似文献   
167.
Despite theoretical associations, there is a lack of empirical studies on the axiological basis of sexual liberalism–conservatism. Two studies demonstrated important associations between these constructs for young adults. In Study 1, participants were 353 undergraduate students with a mean age of 20.13 (SD = 1.84), who completed the Sexual Liberalism–Conservatism Scale and the Basic Values Survey. In Study 2, participants were 269 undergraduate students, with a mean age of 20.3 (SD = 1.82), who completed a social desirability scale in addition to Study 1 instruments. Results showed how values can predict sexual liberalism–conservatism after controlling for social desirability. Attitudes towards one’s own sexual behavior were more conservative whereas attitudes towards other’s sexual behavior were more liberal. Gender was not a significant predictor of sexual attitudes whereas previous sexual experience showed a significant association to this construct. In general, results corroborated previous findings, showing that participants with a tendency to present socially desirable answers also tended to present themselves as sexually conservative.  相似文献   
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