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91.
Discourse changes in early Alzheimer disease,mild cognitive impairment,and normal aging 总被引:3,自引:0,他引:3
Chapman SB Zientz J Weiner M Rosenberg R Frawley W Burns MH 《Alzheimer disease and associated disorders》2002,16(3):177-186
The purpose of this study was to determine the sensitivity of discourse gist measures to the early cognitive-linguistic changes in Alzheimer disease (AD) and in the preclinical stages. Differences in discourse abilities were examined in 25 cognitively normal adults, 24 adults with mild probable AD, and 20 adults with mild cognitive impairment (MCI) at gist and detail levels of discourse processing. The authors found that gist and detail levels of discourse processing were significantly impaired in persons with AD and MCI as compared with normal control subjects. Gist-level discourse processing abilities showed minimal overlap between cognitively normal control subjects and those with mild AD. Moreover, the majority of the persons with MCI performed in the range of AD on gist measures. These findings indicate that discourse gist measures hold promise as a diagnostic complement to enhance early detection of AD. Further studies are needed to determine how early the discourse gist deficits arise in AD. 相似文献
92.
Tractenberg RE Weiner MF Thal LJ 《The Journal of neuropsychiatry and clinical neurosciences》2002,14(1):11-18
To estimate the prevalence of, and develop norms for, significant agitation in community-dwelling persons with Alzheimer's disease (AD), the authors applied three different criteria to persons with AD (n=235) and normal elderly control subjects (NEC; n=64). The criteria were used to identify the minimum total score on the Cohen-Mansfield Agitation Inventory (CMAI) that represents significant or "excessive" agitation and to estimate its prevalence. The "ultraliberal" criterion resulted in 99.1% of persons with AD and 56.6% of NEC being classified as "excessively" disturbed. The "liberal" and "conservative" criteria classified 66.7% and 68.2% of persons with AD, and no NEC, as "excessively" disturbed. The authors conclude that the best estimate of prevalence of excessive agitation in this population is 67.5%, and that individuals with CMAI scores of 0 to 14 probably should not be considered to have excessive agitation. 相似文献
93.
Brain MRI hippocampal volume and prediction of clinical status in a mild cognitive impairment trial 总被引:10,自引:0,他引:10
Grundman M Sencakova D Jack CR Petersen RC Kim HT Schultz A Weiner MF DeCarli C DeKosky ST van Dyck C Thomas RG Thal LJ;Alzheimer's Disease Cooperative Study 《Journal of molecular neuroscience : MN》2002,19(1-2):23-27
Mild Cognitive Impairment (MCI) is considered a transitional stage in the pathogenesis of Alzheimer’s disease; however, not
all MCI patients progress to clinically defined AD or decline at identical rates. Hippocampal atrophy, as measured by Magnetic
Resonance Imaging (MRI), may be a marker for hippocampal pathology in patients with MCI and predict a more rapid deterioration
to clinical AD. In this study, we used MRI data from an ongoing MCI clinical trial to determine whether MRI hippocampal volume
at baseline was associated with cognitive and functional performance in MCI subjects and whether it predicted those individuals
who were more likely to develop AD. We performed correlational analyses between the MRI hippocampal volumes at study entry
and the subjects’ concurrent performance on neuropsychological measures and clinical ratings. Larger hippocampal volume was
associated with better performance on tests of memory, general cognition, and overall clinical ratings. Further analyses suggested
that a smaller baseline hippocampal volume may be associated with a higher risk of developing clinical AD. As the trial is
still ongoing, these results require confirmation once the trial is completed. In summary, these data suggest that MRI hippocampal
volume may be a useful correlate of disease severity in MCI subjects and a prognostic indicator of subsequent AD. 相似文献
94.
Does the level of a leader's spirituality affect his or her effectiveness as a leader? The existence or nonexistence of a link between leadership and spirituality is an emerging issue in the healthcare leadership and management literature. This article defines effective leadership and spirituality and reviews the literature for both healthcare and other organizations in the discussion of this link. It concludes that healthcare leaders who are more developed in terms of their actualized spirituality simultaneously implement the five practices of effective leaders: challenge the process, inspire a shared vision, enable others to act, model the way, and encourage the heart. Moreover, they achieve more positive results for their organizations. 相似文献
95.
96.
Myron F Weiner Rochelle E Tractenberg Shelia Jin Anthony Gamst Ronald G Thomas Elisabeth Koss Leon J Thal 《Journal of psychiatric research》2002,36(1):19-25
We explored the applicability of the standard scoring of the Cohen-Mansfield Agitation Inventory (CMAI), a widely used nursing-home derived instrument, to community-dwelling persons with Alzheimer's disease (AD). Item responses to the CMAI were gathered from participants in two large clinical studies, one of which specifically included patients with behavioral disturbances. Confirmatory factor analysis in these two groups of well-characterized AD patients suggested that conventional CMAI subscoring did not adequately describe the responses of these two groups. Exploratory factor analysis indicated that the four CMAI subscores, based on a verbal-physical and aggressive-non-aggressive conceptualization of behavioral disturbance, did not fit community dwelling persons with AD. Based on cross-sectional and longitudinal analyses, there was suggestive evidence for three behavioral clusters, but these clusters did not achieve statistical significance Overall, the CMAI seemed best suited to describe the overall level rather than the specific subtypes of behavioral dyscontrol in community-dwelling persons with AD. 相似文献
97.
Automated registration of laser Doppler perfusion images by an adaptive correlation approach: application to focal cerebral ischemia in the rat 总被引:3,自引:0,他引:3
Riyamongkol P Zhao W Liu Y Belayev L Busto R Ginsberg MD 《Journal of neuroscience methods》2002,122(1):79-90
Hemodynamic changes are extremely important in analyzing responses from a brain subjected to a stimulus or treatment. The Laser Doppler technique has emerged as an important tool in neuroscience research. This non-invasive method scans a low-power laser beam in a raster pattern over a tissue surface to generate the time course of images in unit of relative flux changes. Laser Doppler imager (LDI) records cerebral perfusion not only in the temporal but also in the spatial domain. The traditional analysis of LD images has been focused on the region-of-interest (ROI) approach, in which the analytical accuracy in an experiment that necessitates a relative repositioning between the LDI and the scanned tissue area will be weakened due to the operator's subjective decision in data collecting. This report describes a robust image registration method designed to obviate this problem, which is based on the adaptive correlation approach. The assumption in mapping corresponding pixels in two images is to correlate the regions in which these pixels are centered. Based on this assumption, correlation coefficients are calculated between two regions by a method in which one region is moved around over the other in all possible combinations. To avoid ambiguity in distinguishing maximum correlation coefficients, an adaptive algorithm is adopted. Correspondences are then used to estimate the transformation by linear regression. We used a pair of phantom LD images to test this algorithm. A reliability test was also performed on each of the 15 sequential LD images derived from an actual experiment by imposing rotation and translation. The result shows that the calculated transformation parameters (rotation: theta =7.7+/-0.5 degrees; translation: Delta x =2.8+/-0.3, Delta?=4.7+/-0.4) are very close to the prior-set parameters (rotation: theta=8 degrees; translation: Delta x=3, Delta y=5). This result indicates that this approach is a valuable adjunct to LD perfusion monitoring. An original sequence of LD images that recorded cerebral perfusion through a cranial window before, during and after middle cerebral artery occlusion (MCAo) is presented, together with the registered image sequence. Cerebral perfusion data acquired in a pixel-based manner from different anatomic locations of the registered LD image sequence are also presented over the whole time-course of the experiment. 相似文献
98.
Effect of ischemic preconditioning on the expression of putative neuroprotective genes in the rat brain 总被引:20,自引:0,他引:20
Truettner J Busto R Zhao W Ginsberg MD Pérez-Pinzón MA 《Brain research. Molecular brain research》2002,103(1-2):106-115
Previous studies have demonstrated that sublethal ischemic insults protect from subsequent ischemia in the intact brain. There are two windows for the induction of tolerance by ischemic preconditioning (IPC). One occurs within 1 h following IPC, and the other one develops from 1 to 3 days after IPC. The goal of this study was to determine whether IPC neuroprotection may be mediated by expression of known neuroprotective genes and to characterize the temporal and spatial expression patterns of these genes. IPC was produced by bilateral carotid artery occlusions and hypotension (50 mmHg) for 2 min. After various survival times, the expression of MAP-2, brain-derived neurotrophic factor (BDNF), c-jun, c-fos, nerve growth factor (NGF) and HSP70 was assessed by in situ hybridization of coronal brain sections with 35S labeled probes. BDNF, NGF, and c-jun were significantly upregulated in the hippocampus. c-fos was detected in the hippocampus, cortex and striatum. HSP70 mRNA was induced in the cortex, hippocampus, striatum, and thalamus. MAP-2 showed no change in expression, confirming previous studies that no cell death occurs following IPC. The increase in expression of these stress-related, neurotrophic and immediate early genes in response to a mild preconditioning insult may help mediate the protection of vulnerable neurons to subsequent lethal ischemic insults. 相似文献
99.
100.
Dickinson BD Genel M Robinowitz CB Turner PL Woods GL 《Medicine and science in sports and exercise》2002,34(10):1539-42; discussion 1543
Gender verification of female athletes has long been criticized by geneticists, endocrinologists, and others in the medical community. Problems include invalid screening tests, failure to understand the problems of intersex, the discriminatory singling out of women based only on laboratory results, and the stigmatization and emotional trauma experienced by individuals screened positive. Genuine sex-impostors have not been uncovered by laboratory-based genetic testing; however, gender verification procedures have resulted in substantial harm to a number of women athletes born with relatively rare genetic abnormalities. Individuals with sex-related genetic abnormalities raised as females have no unfair physical advantage and should not be excluded or stigmatized, including those with 5-alpha-steroid-reductase deficiency, partial or complete androgen insensitivity, and chromosomal mosaicism. In 1990, the International Amateur Athletics Federation (IAAF) called for ending genetic screening of female athletes and in 1992 adopted an approach designed to prevent only male impostors from competing. The IAAF recommended that the "medical delegate" have the ultimate authority in all medical matters, including the authority to arrange for the determination of the gender of the competitor if that approach is judged necessary. The new policy advocated by the IAAF, and conditionally adopted by the International Olympic Committee, protects the rights and privacy of athletes while safeguarding fairness of competition, and the American Medical Association recommends that it become the permanent approach. 相似文献