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Ethanol is a recognized immunosuppressive agent in the chronic alcoholic. However, the effects of ethanol exposure on the developing immune system have not been extensively investigated. This study evaluated the effects of early postnatal ethanol exposure, via breast milk, on splenic lymphocyte differentiation antigen expression in offspring reared by ethanol-fed mice. Maternal mice were fed a liquid diet containing 20% ethanol-derived calories during pregnancy (E-P), pregnancy and lactation (E-PL), or lactation (E-L). Ad libitumfed (C) and pair-fed (PF) control groups, fed a control liquid diet, were included. Expression of differentiation antigens on splenic lymphocytes from 21-day-old offspring reared by females in 1 of the 3 ethanol exposure conditions was evaluated by flow cytometry. Offspring reared by E-P females had similar numbers of splenic lymphocytes as offspring reared by C and pair-fed during pregnancy (PF-P) females. In contrast, offspring reared by E-PL and E-L females had fewer splenic lymphocytes than both PF-PL and PF-L (respectively), and C offspring. The number of Thy 1.2+, CD4+, CD8+, and IgG+ (B-cell) splenic lymphocytes was reduced in E-PL and E-L offspring compared with PF and C offspring. E-P offspring had fewer CD4+ and IgG+ splenic lymphocytes than C, but not PF-P, offspring. The percentage of Thy 1.2+ splenic lymphocytes was significantly reduced among E-PL and E-L offspring compared with PF-PL and PF-L (respectively), and C offspring. These results suggest that ethanol exposure of female mice during pregnancy, pregnancy and lactation, or lactation alone, alters the phenotypic development of splenic lymphocytes of offspring reared by these females. The greatest effect on differentiation antigen expression occurred when females consumed ethanol during the period of lactation. We speculate that direct exposure of the nursing offspring to ethanol via the breast milk was responsible for the reductions in specific splenic lymphocyte populations. These data demonstrate that mice reared by females fed ethanol during the early postnatal period have a marked depletion of each of the major subpopulations of splenic lymphocytes, and that Thy 1.2+ lymphocytes are differentially sensitive to ethanol.  相似文献   
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The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions.  相似文献   
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PURPOSE: The purpose of this study was to develop and evaluate measures reflecting the onset of tense marking for children between the ages of 2;0 (years;months) and 3;0. METHOD: The validity of 4 cumulative measures of tense marker emergence and productivity was evaluated relative to existing measures of early grammatical development in a sample of 20 children followed longitudinally. Fourteen children were at risk for specific language impairment (AR-SLI group), and 6 children had low average language abilities (LA group). RESULTS: All measures of onset were highly correlated with the traditional measures; however, children's progress toward mastery of grammatical tense marking was best explained by the productivity of their tense marking systems. Finally, the onset measures imposing productivity requirements best differentiated children in the LA group from those in the AR-SLI group. CONCLUSIONS: The clinical implications for using the late onset of tense marking to improve the early identification of SLI are discussed.  相似文献   
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Complementary modalities, used alone or in combination with pharmacologic therapies, play an important role in the prevention and management of postoperative nausea and vomiting (PONV) and post discharge nausea and vomiting (PDNV). This article will review the evidence for the effective use of complementary modalities: acupuncture and related techniques, aromatherapy, and music therapy that may be integrated in the perianesthesia nurse's plan of care to prevent or manage PONV.  相似文献   
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Background: The effects of epidural needle design, angle, and bevel orientation on cerebrospinal fluid leak after puncture have not been reported. The impact of these factors on leak rate was examined using a dural sac model. Dural trauma was examined using scanning electron microscopy.

Methods: Human cadaveric dura, mounted on a cylindrical model, was punctured with epidural needles using a micromanipulator. Tissue was punctured at 15 cm H2O (left lateral decubitus) system pressure, and leak was measured at 25 cm H2O (semisitting) pressure. Leak rates and trauma were compared for the following: (1) six different epidural needles at 90[degrees], bevel parallel to the dural long axis; (2) 18-gauge Tuohy and 18-gauge Special Sprotte(R) epidural needles, 30[degrees]versus 90[degrees]; (3) 18-gauge Tuohy, bevel perpendicular versus parallel to the dural long axis.

Results: With the 90[degrees] puncture, bevel parallel, the greatest leak occurred with a 17-gauge Hustead (516 +/- 319 ml/15 min), and the smallest leak occurred with a 20-gauge Tuohy (100 +/- 112 ml/15 min; P = 0.0018). A 20-gauge Tuohy puncture led to statistically significant reductions in leak (P value range, 0.0001-0.0024) compared with all needles except the Special Sprotte(R). With the 30[degrees]versus 90[degrees] angle, 30[degrees] punctures with an 18-gauge Tuohy produced nonstatistically significant leak reductions compared with the 18-gauge Tuohy at 90[degrees]. The puncture angle made no difference for the Special Sprotte(R). Nonsignificant reductions were found for the Special Sprotte(R) compared with the Tuohy. With the 18-gauge Tuohy bevel orientation, perpendicular orientation produced nonstatistically significant reductions in leak compared with parallel orientation.  相似文献   

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