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Aged and young adults were tested by category cued recall after learning with category cues (CCR) or with item cues (ICR). CCR was about twice ICR for both aged and young adults. The aged recalled less than the young and did not benefit as much from greater encoding specificity and deeper processing in CCR. ICR and CCR were correlated, so that expected CCR can be predicted from ICR. The regression of CCR on ICR was linear for young adults, but was piecewise linear for the aged, showing that the relationship between ICR and CCR was not uniform for the aged adults. Lower than expected CCR by a subset of aged without clinical dementia may be a sign of preclinical dementia.  相似文献   
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Overexpression of HER2 in estrogen receptor (ER)-positive human breast tumors has been associated with resistance to endocrine therapy. Here we investigated the effects of HER2 on expression of apoptotic pathways and modulation of tamoxifen-induced apoptosis in ER-positive MCF-7 breast cancer cells. We report that HER2 overexpression in MCF-7 cells is accompanied by up-regulation of antiapoptotic Bcl-2 and Bcl-XL proteins and suppression of tamoxifen-induced apoptosis. In addition, human tumor cell lines that are both ER positive and overexpress HER2 also express enhanced levels of Bcl-2 compared to cells that are either ER positive or overexpress HER2 alone. Our findings suggest that possible deregulation of antiapoptotic Bcl-2 and Bcl-XL may be associated with the enhanced survival of HER2-overexpressing and ER-positive breast cancer cells treated with antiestrogens.  相似文献   
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We analysed 42 differentiated thyroid tumors including 15 follicular adenomas (FA), 13 papillary thyroid cancers (PTC) and 14 follicular thyroid carcinomas (FTC) with 13 microsatellite markers specific for the long arm of human chromosome 7 within 7q31; this region is deleted frequently in several other tumor types. Overall, 20 of the 42 samples analysed (48%) displayed LOH with one or more of the markers tested. LOH was detected most frequently (78%) in FTC, the most malignant of the thyroid tumors. A smallest common deleted region (SCDR) was defined in this tumor type flanked by markers D7S480 and D7S490. This SCDR is distinct from D7S522, the most commonly deleted locus in many other tumors, which was deleted in only one FTC. D7S522 did show LOH in two of six informative PTCs. None of the PTC and only two of the FAs showed LOH in the FTC SCDR. Since FA is considered a premalignant stage of FTC, our results suggest that inactivation of a putative tumor suppressor at 7q31.2 may be acquired during adenoma to carcinoma progression. The absence of LOH at this locus amongst PTC suggests that inactivation of this tumor suppressor is specific for FTC. In conclusion, LOH at 7q31 is a frequent event in differentiated thyroid cancer, and we have defined a 2 cM SCDR specific for FTC.  相似文献   
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The landmark U.S. Supreme Court case of Daubert v. Merrell Dow Pharmaceuticals , which overturned the venerable Frye test for the admissibility of scientific evidence, has sparked considerable interest among scholars and practitioners, within both the law and the various sciences. The discussion of the impact of Daubert on social science evidence, however, has been largely confined to a narrow range of issues, primarily concerning criminal law and mental health. Indeed, the Daubert case thus far has received relatively scant attention in the published cases involving business litigation, and in most of these instances, the focus has been on evidence from the hard sciences rather than from the social sciences. The author explores the use and acceptance of social science evidence in business litigation within the post- Daubert era. First, the specific Daubert factors are analyzed from the perspective of social science evidence in business litigation. Second, the scope of business litigation which has been impacted-or which is potentially impacted-by Daubert is outlined and discussed. Third, various procedural issues in the post- Daubert era are explored, including motions for summary judgment to dispose of social science issues… (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this study, high-efficiency packed capillary reversed-phase liquid chromatography (RPLC) coupled on-line with high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been investigated for the characterization of complex cellular proteolytic digests. Long capillary columns (80-cm) packed with small (3-micron) C18 bonded particles provided a total peak capacity of approximately 1000 for cellular proteolytic polypeptides when interfaced with an ESI-FTICR mass spectrometer under composition gradient conditions at a pressure of 10,000 psi. Large quantities of cellular proteolytic digests (e.g., 500 micrograms) could be loaded onto packed capillaries of 150-micron inner diameter without a significant loss of separation efficiency. Precolumns with suitable inner diameters were found useful for improving the elution reproducibility without a significant loss of separation quality. Porous particle packed capillaries were found to provide better results than those containing nonporous particles because of their higher sample capacity. Two-dimensional analyses from the combination of packed capillary RPLC with high-resolution FTICR yield a combined capacity for separations of > 1 million polypeptide components and simultaneously provided information for the identification of the separated components based upon the accurate mass tag concept previously described.  相似文献   
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Details of the construction and operation of a lead, liquid argon electromagnetic calorimeter used in Fermilab experiment E515 are presented. The system had an active projected area of 1.2×2.4 m2. Its performance in low intensity electron beams and in exposure to intense, high multiplicity 200 GeV/c π? Be interactions are described.  相似文献   
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