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1.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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The aim is to compare the mean values of the in vivo electrical characteristics of bioiogical active points (BAPs) with those of the surrounding human skin. The impedance measurements at BAPs and on the surrounding skin are carried out in vivo on ten young, healthy people. The results of the measurements show that the BAP resistance RP is smaller, and the capacitance CP is higher, than the corresponding values for skin, RS and CS, respectively, these differences are larger at low frequencies (at f=3 Hz, RS/RP=3.19 and CP/CS=3.2). The mean values of the impedance measurements at the BAPs are different from those measured on the skin. The dependence of RP and CP on the pressing force, in the range of about 1–5 N, for the BAPs, has a smaller slope than that observed for the surrounding skin. An equivalent circuit for the BAPs is proposed that describes sufficiently well the experimental results obtained. These results show that the large dispersion in the observed impedance characteristics of the human body measurements in different body regions can be related to the influence of the BAPs present under the electrodes.  相似文献   
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Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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BACKGROUND: Major life transitions (e.g., graduation from high school) are times when many changes occur in a person's social and physical environment. Men and women likely experience aspects of these changes differently. As a result, health-related behaviors likely change at these times with possible differences in these changes by gender. METHODS: Gender differences in the performance of chronic disease risk-related behaviors (fruit, juice, and vegetable intake; physical activity; tobacco and alcohol use; and sexual practices) through the transition out of high school (HS) were assessed in a secondary analysis of a nationally representative sample from the 1992 National Health Interview Survey-Youth Risk Behavior Survey. The survey was completed by 5881 young people aged 14 to 21 years. Regression discontinuity analysis with piecewise regression was performed. RESULTS: Statistically significant gender by transition effects were obtained for exercise/physical activity (decreases at the transition point for males), snuff use (decrease for females in HS), binge drinking and number of days drinking alcohol (increases for males at the transition point), and use of alcohol or drugs before sexual intercourse (decrease for females post HS). Fruit intake decreased for males and females and daily and heavy cigarette smoking increased during the HS years. Effect sizes were small but promising, given that the data set was not designed to test this hypothesis. CONCLUSION: These data offer evidence of differences by gender in chronic disease risk behaviors through the HS transition. Longitudinal studies are needed to assess the true nature of these differences, the tracking of these risk behaviors and their personal, social, and environmental determinants, including gender-specific determinants, that may explain these changes and inform future intervention development.  相似文献   
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The paper deals with the results and efficiency of organizing emergency medical aid to victims in railway accidents, crashes, and other emergencies in the past years. It presents the data of researches, which characterizes the specific features of railway injury, which should be taken into account in planning and organizing a medical aid to suffered passengers and railway workers. The authors have developed and proposed guidelines for improving health care to emergency victims by railway therapeutical and prophylactic and sanitary facilities.  相似文献   
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