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41.
Human tracheobronchial clearance was studied with a test aerosol of monodisperse particles (approximately 7μ) of fluorinated ethylene propylene (Teflon 120) tagged with radioactive fluorine (18F), a positron emitter with a half-life of 110 minutes. Eight subjects were exposed twice to the test aerosol. The clearance differed appreciably between the individuals but the two determinations in the same individual are highly similar. The test aerosol employed should be suitable for intraindividual studies of tracheobronchial clearance in man and consequently of value for investigating the acute effect of different substances on tracheobronchial clearance.  相似文献   
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Focal nodular hyperplasia occurring after blunt abdominal trauma   总被引:2,自引:0,他引:2  
Focal nodular hyperplasia of the liver is a benign neoplasm. The pathogenesis is unknown, but it was hypothesized that focal nodular hyperplasia may be a response to a vascular abnormality. We report on a case of focal nodular hyperplasia that developed in a young patient 1 year after a blunt hepatic injury.  相似文献   
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Limited data are available on the longitudinal occurrence of syndemic factors among women at risk for HIV infection in the USA and how these factors relate to sexual risk over time. HVTN 906 was a longitudinal study enrolling 799 HIV-uninfected women in three cities. Assessments were done at baseline, 6, 12, and 18 months to assess syndemic factors (low education, low income, unemployment, lack of health insurance, housing instability, substance use, heavy alcohol use, partner violence, incarceration) and sexual risk outcomes. For each sexual risk outcome, a GEE model was fit with syndemic factors or syndemic score (defined as sum of binary syndemics, ranging from 0 to 9), visit, study site, age and race/ethnicity as predictors to examine the multivariable association between syndemic factors and outcomes over time. Odds of unprotected sex while drunk or high were significantly higher when women reported lack of health insurance, substance and heavy alcohol use and partner violence. Housing instability, substance and heavy alcohol use, partner violence and recent incarceration were associated with higher odds of having multiple sexual partners. Odds of sex exchange were significantly higher in the presence of unemployment, housing instability, low education, lack of health insurance, substance and heavy alcohol use, partner violence and incarceration. Housing instability, substance and heavy alcohol use, and partner violence were significantly associated with higher odds of unprotected anal sex. Odds of having a recent STI were significantly higher when women reported housing instability and partner violence. There were significantly higher odds of the reporting of any risk outcomes during follow-up with higher syndemic score. This study highlights a group of women experiencing multiple poor social and health outcomes who need to be the focus of comprehensive interventions.  相似文献   
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Journal of Thrombosis and Thrombolysis - To study whether a diagnosis of cancer affects the clinical presentation and outcomes of patients with pulmonary embolism (PE). A retrospective analysis was...  相似文献   
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BACKGROUND: Corticopontocerebellar and cerebellothalamocortical circuits underlie a wide range of neuropsychological processes compromised by alcoholism. The analyses herein tested whether abnormalities of volumes of brain structures forming nodes of these separate feed-forward and feedback systems are selectively related to each other and whether any of these noncortical regions can account for cognitive and motor deficits occurring as sequelae of chronic alcoholism. METHODS: Regional brain measures originated from our prior neuroimaging studies, showing in alcoholics significant volume deficits in the principal structures of interest: cerebellar hemispheres, vermis, pons, and thalamus as well as prefrontal, frontal, and parietal cortex. Neuropsychological functions targeted for analysis-problem solving, visuospatial ability, and static postural stability-showed 0.6 to 1.6 SD deficits in these alcoholic men. RESULTS: In alcoholics, the patterns of correlations were consistent with dissociation of thalamic and pontine circuitry. Pontine and thalamic volumes were not correlated with each other. Pontine volumes correlated with white matter volumes of anterior superior vermis and gray and white matter volumes of the cerebellar hemispheres but not with cortical regional volumes. Thalamic volumes correlated with gray matter volumes of the cerebellar hemispheres, parietal cortex, and inferior posterior vermian lobule, which itself correlated with parietal, prefrontal, and frontal cortical volumes. Controls did not show these correlational patterns. Brain structure-function relationships in alcoholics examined with multiple regression identified anterior vermian but not prefrontal or parietal volume as a unique predictor of balance scores; vermian and thalamic but not prefrontal cortical volumes as predictors of card sorting scores; and cerebellar hemispheric white matter but not parietal cortical volume as a predictor of visuospatial ability. CONCLUSIONS: Each major node of frontocerebellar circuitry shows volume deficits in alcoholics but can be independently compromised. Disruption of these circuits may underlie alcoholism-related neuropsychological deficits, either by abnormalities present in individual nodes or by disconnection via interruption of selective circuitry.  相似文献   
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