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1.
The purpose of this study was to determine the prevalence, course, and risk factors for executive impairment in patients hospitalized on a general medicine service. One hundred patients were administered the Executive Interview (EXIT25), the Executive Clock Drawing Task (CLOX), and the Mini-Mental State Examination at admission and discharge. Fifty-two percent of the patients at admission and 56% at discharge had scores indicating impairment on at least one measure of executive function. Median scores on every measure improved during hospitalization. Older patients and those with a cardiac or gastrointestinal disorder were more likely to have executive impairment. The prevalence of executive impairment on general medicine services is high. Although improvement in executive function occurs during hospitalization, many patients remained impaired.  相似文献   
2.
BACKGROUND. Bilateral blindness unrelated to simple refractive error is twice as prevalent among blacks as among whites, although the difference narrows among the elderly. The reasons for this race- and age-related pattern are uncertain. METHODS AND RESULTS. A randomly selected, stratified, multistage cluster sample of 2395 blacks and 2913 whites 40 years of age and older in East Baltimore underwent detailed ophthalmic examinations by a single team. We identified 64 subjects who were blind in both eyes. The leading causes of blindness were unoperated senile cataract (accounting for blindness in 27 of the total of 128 eyes), primary open-angle glaucoma (17 eyes), and age-related macular degeneration (16 eyes). Together, these three disorders accounted for 47 percent of all blindness in this sample. Unoperated cataract accounted for 27 percent of all blindness among blacks, among whom it was four times more common than among whites; whites were almost 50 percent more likely than blacks to have undergone cataract extraction before the age of 80 (P less than 0.002). Primary open-angle glaucoma accounted for 19 percent of all blindness among blacks; it was six times as frequent among blacks as among whites and began 10 years earlier, on average. By contrast, age-related macular degeneration resulting in blindness was limited to whites, among whom it was the leading cause of blindness (prevalence, 2.7 per 1000; 95 percent confidence interval, 1.2 to 5.4); it affected 3 percent of all white subjects 80 years of age or older. CONCLUSIONS. The pattern of blindness in urban Baltimore appears to be different among blacks and whites. Whites are far more likely to have age-related macular degeneration, and blacks to have primary open-angle glaucoma. The high rate of unoperated cataracts among younger blacks and among elderly subjects of both races suggests that health services are underused. Half of all blindness in this urban population is probably preventable or reversible.  相似文献   
3.
Increasing interest in studies of prenatal human brain development, particularly using new single-cell genomics and anatomical technologies to create cell atlases, creates a strong need for accurate and detailed anatomical reference atlases. In this study, we present two cellular-resolution digital anatomical atlases for prenatal human brain at postconceptional weeks (PCW) 15 and 21. Both atlases were annotated on sequential Nissl-stained sections covering brain-wide structures on the basis of combined analysis of cytoarchitecture, acetylcholinesterase staining, and an extensive marker gene expression dataset. This high information content dataset allowed reliable and accurate demarcation of developing cortical and subcortical structures and their subdivisions. Furthermore, using the anatomical atlases as a guide, spatial expression of 37 and 5 genes from the brains, respectively, at PCW 15 and 21 was annotated, illustrating reliable marker genes for many developing brain structures. Finally, the present study uncovered several novel developmental features, such as the lack of an outer subventricular zone in the hippocampal formation and entorhinal cortex, and the apparent extension of both cortical (excitatory) and subcortical (inhibitory) progenitors into the prenatal olfactory bulb. These comprehensive atlases provide useful tools for visualization, segmentation, targeting, imaging, and interpretation of brain structures of prenatal human brain, and for guiding and interpreting the next generation of cell census and connectome studies.  相似文献   
4.

Background

Can an information intervention facilitated by information technology and carried out by an interdisciplinary team comprising medical students, technical experts, and the community itself make a positive contribution in reducing the burden of malaria at the village level?In Mifumi village in Eastern Uganda, MIFUMI Project, Makerere University College of Health Sciences Community Based Education and Service program (COBES), and the U.S. National Library of Medicine carried out a series of activities between 2007 and 2010.

Methods

The team surveyed the community''s knowledge of malaria prevention and treatment; implemented a health information intervention using tutorials in a variety of media; and observed the community''s use of previously distributed insecticide treated nets (ITNs) using a digital pen application.

Results

As a result of concerted education and outreach, the village residents have a good understanding of malaria prevention and treatment seeking behaviors. Leveraging the power of information technology and interdisciplinary teamwork, medical students and the denizens of a rural community were able to engage in an interactive experience of health education and promotion.

Conclusion

Preliminary observations suggest that a health information intervention in concert with a collaborative community effort of education and prevention can build capacity within a community to take control of its own health.  相似文献   
5.
6.
We explored relationships between decline in cognitive processing speed (CPS) and change in frontal lobe MRI/MRS-based indices of cerebral integrity in 38 healthy adults (age 57–90 years). CPS was assessed using a battery of four timed neuropsychological tests: Grooved Pegboard, Coding, Symbol Digit Modalities Test and Category Fluency (Fruits and Furniture). The neuropsychological tests were factor analyzed to extract two components of CPS: psychomotor (PM) and psychophysical (PP). MRI-based indices of cerebral integrity included three cortical measurements per hemisphere (GM thickness, intergyral and sulcal spans) and two subcortical indices (fractional anisotropy (FA), measured using track-based spatial statistics (TBSS), and the volume of hyperintense WM (HWM)). MRS indices included levels of choline-containing compounds (GPC + PC), phosphocreatine plus creatine (PCr + Cr), and N-acetylaspartate (NAA), measured bilaterally in the frontal WM bundles. A substantial fraction of the variance in the PM-CPS (58%) was attributed to atrophic changes in frontal WM, observed as increases in sulcal span, declines in FA values and reductions in concentrations of NAA and choline-containing compounds. A smaller proportion (20%) of variance in the PP-CPS could be explained by bilateral increases in frontal sulcal span and increases in HWM volumes.  相似文献   
7.
This report reviews the state of the literature and opportunities for research related to "executive control function" (ECF). ECF has recently been separated from the specific cognitive domains (memory, language, and praxis) traditionally used to assess patients. ECF impairment has been associated with lesions to the frontal cortex and its basal ganglia-thalamic connections. No single putative ECF measure can yet serve as a "gold standard." This and other obstacles to assessment of ECF are reviewed. ECF impairment and related frontal system lesions and metabolic disturbances have been detected in many psychiatric and medical disorders and are strongly associated with functional outcomes, disability, and specific problem behaviors. The prevalence and severity of ECF deficits in many disorders remain to be determined, and treatment has been attempted in only a few disorders. Much more research in these areas is necessary.  相似文献   
8.
BACKGROUND: Tricyclic antidepressants (TCA) provide less than satisfactory pain relief for postherpetic neuralgia (PHN), and the role of opioids is controversial. OBJECTIVE: To compare the analgesic and cognitive effects of opioids with those of TCA and placebo in the treatment of PHN. METHODS: Seventy-six patients with PHN were randomized in a double-blind, placebo-controlled, crossover trial. Each subject was scheduled to undergo three treatment periods (opioid, TCA, and placebo), approximately 8 weeks' duration each. Doses were titrated to maximal relief or intolerable side effects. The primary outcome measures were pain intensity (0 to 10 scale), pain relief (0 to 100%), and cognitive function. Analyses included patients who provided any pain ratings after having received at least a single dose of a study medication. RESULTS: Fifty patients completed two periods, and 44 patients completed all three. Mean daily maintenance doses were morphine 91 mg or methadone 15 mg and nortriptyline 89 mg or desipramine 63 mg. Opioids and TCA reduced pain (1.9 and 1.4) more than placebo (0.2; p < 0.001), with no appreciable effect on any cognitive measure. The trend favoring opioids over TCA fell short of significance (p = 0.06), and reduction in pain with opioids did not correlate with that following TCA. Treatment with opioids and TCA resulted in greater pain relief (38 and 32%) compared with placebo (11%; p < 0.001). More patients completing all three treatments preferred opioids (54%) than TCA (30%; p = 0.02). CONCLUSIONS: Opioids effectively treat PHN without impairing cognition. Opioids and TCA act via independent mechanisms and with varied individual effect.  相似文献   
9.
BACKGROUND: In contrast to perioperative stroke, much less attention has been paid to those with evidence of diffuse brain encephalopathy, presenting as delirium, confusion, coma, and seizures in the immediate postoperative period. OBJECTIVE: To determine the incidence, consequences, and predictive factors for encephalopathy and stroke following coronary artery bypass grafting. METHODS: In a prospective evaluation of 2711 patients operated on between January 1, 1997, and December 31, 2000, preoperative risk factors were obtained before surgery and postoperative outcomes, encephalopathy and stroke, were determined on a daily basis. All strokes were confirmed by neurologic consultation and, in most instances, by imaging. Logistic regression analyses were performed to determine risk factors for these outcomes. RESULTS: The incidence of encephalopathy was 6.9% and of stroke, 2.7%. For patients without either of these outcomes, the average length of stay in the hospital was 6.6 days and the mortality was 1.4%. In contrast, patients with encephalopathy had a length of stay of 15.2 days and a mortality of 7.5%, and those with stroke, a length of stay of 17.5 days and a mortality of 22.0%. Predictive models were developed for encephalopathy involving 5 preoperative factors (age, past stroke, carotid bruit, hypertension, and diabetes) and 1 perioperative factor (time on cardiopulmonary bypass). The model for stroke involved only 3 preoperative risk factors (past stroke, hypertension, and diabetes). CONCLUSIONS: Encephalopathy or stroke is associated with significant increases in length of stay and mortality after coronary artery bypass grafting. Patients at higher risk for these outcomes can be identified before surgery.  相似文献   
10.
OBJECTIVES: To determine whether or not (1) impaired olfactory function is associated with impaired memory on neuropsychological testing in healthy retirees, and if so then (2) whether memory impairment is most consistent with a mesiotemporal rather than frontal system disorder. METHODS: 173 independent residents of a continuing care retirement community were studied. Subjects completed the University of Pennsylvania Smell Identification Test (UPSIT) and a battery of both general and specific cognitive measures that included the Mini-Mental State Examination (MMSE) and the Executive Interview (EXIT25). Subjects were examined twice over 3 years. RESULTS: UPSIT performance was normal in 21% and in the 'anosmic' range in 25% of subjects. Anosmic UPSIT performance was associated with significantly worse performance on all cognitive tests. However, only short-term verbal memory was independently associated with UPSIT-defined anosmia. This association remained significant after adjusting for the other cognitive and sociodemographic variables. The memory deficits of anosmic subjects were qualitatively consistent with a cortical type (type 1) dementing illness such as Alzheimer's disease (AD). Over time, UPSIT-defined 'anosmic' cases suffered significantly greater declines on both the MMSE and the EXIT25, independently of baseline age, gender and MMSE score. CONCLUSIONS: Impaired odor identification in individuals without overt dementia is associated with an AD-like memory impairment and an increased rate of cognitive decline. The comorbid association of these deficits is consistent with the known hierarchical spread of preclinical AD pathology and may be a specific indicator of future clinical AD dementia.  相似文献   
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