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At the time of hire, 4059 of 6522 healthcare workers required a 2-step tuberculin skin test; 114 workers (2.8%) demonstrated a boosted reaction after the second step. Boosted reactions were significantly associated with male sex and older age. A verbal history of previous tuberculin skin test results was not a reliable indicator of baseline tuberculin skin test status at the time of hire.  相似文献   
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The significance of life stress, coping, and social support was examined in relation to depressive symptomatology in a sample of 160 asymptomatic and mildly symptomatic HIV-antibody-positive (HIV+) men. The participants (mean age = 32 years) were interviewed about the life stress that they had experienced in the previous 6  相似文献   
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The relationships between doppler-sonographic determination of systolic, diastolic flow velocity and pulsation index in the A. cerebri anterior and developmental outcome at 12 month of age were studied by means of multivariate variance and discriminance analysis. The study involves 92 preterm infants, in whom flow measurement were performed in the first 3 days and the second week of life. The influence of additional perinatal risk factors like Apgar score, blood gas values and type of intensive care were taken in consideration: Doppler-sonographic flow parameters were found to be necessary coefficients of statistically significant discriminant functions, which differentiate between infants with normal or delayed psycho-motoric development or cerebral palsy. However, in comparison to the other risk factors their weight for differentiation is low. Parameters of immediate postnatal adaptation like apgar score and blood gas values decide quality of developmental outcome in infants with as well as without ultrasonographically proven neonatal brain damage. In infants with neonatal ventricular hemorrhages only a distinct influence of immaturity was observed additionally.  相似文献   
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Test properties of the Millon Clinical Multiaxial Inventory (MCMI) were examined in a sample of 419 sex offenders and controls in three different settings. The offender group included sexual aggressives, pedophiles, incest perpetrators and miscellaneous cases. Nineteen of the 20 scales of the MCMI had alpha reliability over 0.60 and for 13 scales it was over 0.80. The scales showed satisfactory discriminant validity from age but 9 scales showed a moderate influence of intelligence scores and education. Criminal history did not influence scale results. The scales unfortunately did show significant correlations with MMPI validity scales. Although the scales were not susceptible to naive lying, they were influenced by social desirability especially. Four factors were extracted in principal axes factor analysis that accounted for 91.2% of the total variance. The first factor explained 58.2% of the variance and was labeled general psychopathology. The other three factors suggested psychotic tendencies, extraversion and the bipolar dependency-antisocial tendencies. When the groups were compared, almost all scales significantly differentiated them. When the MMPI F-K Scale was forced to enter a stepwise discriminant analysis first, five scales still were significant; Narcissistic, Schizoid-Asocial, Alcohol Abuse, Paranoid, & Dependent-Submissive scales. The MCMI taps important dimensions in sex offenders but suffers from validity problems.  相似文献   
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BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours.  相似文献   
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The glucose deprivation-induced release of [3H]D-aspartate was studied in bovine and human retinas in a superfusion apparatus. [3H]D-aspartate release was significantly increased upon omitting glucose in the superfusion buffer. This effect was dependent on external Ca2+ because L- and N-type Ca2+-channel blockers, such as diltiazem (1 microM), nitrendipine (1 microM), and omega-conotoxin (100 nM), significantly reduced the effect of glucose-deprivation induced release of [3H]D-aspartate. Furthermore, while glutamate receptor agonists (L-glutamate, N-methyl-D-aspartate, but not kainate) potentiated the effects of glucose deprivation, antagonists (MK-801, MCPG, ifenprodil, and L-AP3) at these receptors blocked the glucose deprivation-induced release process. Taken together, these studies have demonstrated that under conditions of glucose deprivation, as may happen during ischemic events in vivo, the retinal glutamatergic nerve endings and/or glial cells promote the efflux of [3H]D-aspartate into the extracellular environment. This process appears to be receptor-mediated and dependent on extracellular Ca2+ and is similar to previous reports pertaining to brain tissues.  相似文献   
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