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41.
Long-term potentiation (LTP) in perforant path-granule cell synapses has been shown to be accompanied by an increase in glutamate release. The objective of this study was to examine the possibility that nerve growth factor (NGF), by activating tyrosine kinase, modulates glutamate release and, therefore, contributes to expression of LTP in dentate gyrus. The data indicate that NGF, in the presence of trans-1-aminocyclopentyl-1,3-dicarboxylate (ACPD), enhanced KCI-stimulated release and KCI-stimulated calcium influx in vitro and that these effects were blocked by the tyrosine receptor kinase (trk) inhibitor tyrphostin AG879. The data also indicate that NGF increased phosphorylation of trkA and the mitogen-activated protein kinase extracellular signal-regulated kinase (ERK) in dentate gyrus in vitro. In addition to its effects in vitro, tyrphostin AG879 inhibited the expression of LTP in perforant path-granule cell synapses and the accompanying increase in transmitter release. Analysis of phosphorylation of the two tyrosine kinase substrates trkA and ERK in synaptosomes prepared from untetanized and tetanized dentate gyrus revealed that LTP was associated with increased phosphorylation of both proteins; no evidence of such a change was observed in either tetanized or untetanized tissue prepared from tyrphostin-pretreated rats. These findings are consistent with the hypothesis that NGF, by interacting with trkA, triggers a sequence of tyrosine kinase-dependent phosphorylation steps that modulate glutamate release and calcium influx and impact on expression of LTP in dentate gyrus.  相似文献   
42.
Year 5 of the Massachusetts Behavioral Health Program was a transition to management by a new private managed care organization. Fifty-eight providers interviewed for an ongoing panel survey reported slightly lower levels of quality, access, utilization, and length of stay than a year earlier. Relationships with providers and advocates improved after an initial difficult period, while consumer and family involvement at all levels remained low. The greatest changes in managed care appeared to take place during the initial transition from fee-for-service care, but intractable problems continue, and full participation of stakeholders seems difficult to achieve.  相似文献   
43.
Biliary tract disease is a relatively uncommon, heterogenous disease in pregnancy. Specifically, acute cholecystitis can be especially difficult to recognize in pregnancy. However, once diagnosed, the initial management plan should be conservative and include antibiotic therapy. Subsequent management depends on the gestational age at diagnosis. Surgical therapy, when indicated, should not be delayed and a planned intervention during the second trimester appears to offer a better outcome than surgery performed under emergent conditions.  相似文献   
44.
The present report describes a four-week trial at the Victoria General Hospital, Halifax, to determine the effect of access to a computer system on nutrient intake analyses, the problems in implementation of the system, and the response of the staff dietitians. An on-line system was obtained from the Ohio State University Hospitals and modified to reflect Canadian food and nutrient content, and to include some additional program features. Twelve hundred and eighty-six foods were characterized according to 15 food components, the system was responsive to nine interactive commands, and there were nine possible print-out formats of calculations. The results of the trial reinforced the expectation of greatly increased work efficiency, however, the system was not utilized to its potential. Some technical problems were largely overcome within the first week of operation. However, needs relating to the extensiveness of the food and nutrient data base, and the methodologies and time for obtaining and evaluating individual dietary intake information prevented maximum efficiency. The dietitians liked the comprehensiveness and detail of the system, however, routine dietary intake collections were too time-consuming for their present work schedules.  相似文献   
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This study investigated the effects of visual vs. verbal processing style preferences on immediate recall accuracy for the Rey-Osterrieth and Taylor Complex Figure Tests. Undergraduates were classified as visualizers or verbalizers and asked to copy either the Rey-Osterrieth or Taylor figure and then draw it from memory. A subset of subjects reported the strategy they used to reproduce the figure. Visualizers showed better reproduction accuracy than verbalizers for the Rey-Osterrieth test, and for this test approximately 80% of verbalizers as well as visualizers reported using a visual strategy. For the Taylor, no effect of processing style was obtained, and close to half of the verbalizers (43%) reported using their preferred verbal strategy, while 82% of the visualizers used a visual strategy. These results suggest that a general preference for thinking "in images" is important for predicting visual memory accuracy only on tests such as the Rey-Osterrieth which do not lend themselves easily to a verbal strategy. In contrast, for the Taylor test, deficits to the visual imagery system may be circumvented and obscured by the verbalizers' use of verbal recall strategies. Thus, in test batteries, the Rey-Osterrieth and the Taylor Tests should not be used interchangeably.  相似文献   
48.
A woman with Friedreich's ataxia, a hereditary neurodegenerative disorder affecting primarily the spinal cord and cerebellum, had intractable depression in the context of bipolar disorder. Electroconvulsive therapy resulted in substantial improvement of depressive symptoms while not adversely affecting the patient's neurologic status.  相似文献   
49.
Anti-inflammatory drugs protect against Alzheimer disease at low doses   总被引:6,自引:0,他引:6  
CONTEXT: Anti-inflammatory medications have an inverse association with Alzheimer disease (AD). OBJECTIVES: To examine at what doses this anti-inflammatory drug effect occurs and whether other medications and/or International Classification of Diseases, Ninth Revision, Clinical Modification diagnoses affect the association. DESIGN: Subjects 75 years and older from a random population sample were classified by consensus using International Classification of Diseases, Ninth Revision, Clinical Modification diagnoses. Drug associations with different types of dementia with and without the International Classification of Diseases, Ninth Revision, Clinical Modification diagnoses as well as dosage data were analyzed. SETTING: The Centre for Education and Research on Aging, Concord Hospital, Concord, Australia. PATIENTS: The Sydney Older Persons Study recruited 647 subjects (average age, 81 years). A total of 163 patients were given diagnoses placing them in different dementia categories and were compared with 373 control subjects. Of the patients with dementia, 78 had AD without vascular dementia, 45 had vascular dementia (permissive of other dementia diagnoses), and 40 had other dementia diagnoses (without AD or vascular dementia). MAIN OUTCOME MEASURES: Fifty drugs or drug groups were subjected to a 2 (drug used vs drug not used) x 4 (dementia and control groups) chi(2) analysis. Drugs with inverse associations were identified and potential confounders (logistic regression) and dosage data (exact small sample 1-tailed tests) analyzed. RESULTS: As expected, there was an inverse association between nonsteroidal anti-inflammatory drugs and aspirin (and unexpectedly angiotensin-converting enzyme inhibitors) and AD. This association was not observed with vascular dementia or any other diagnoses. Analysis showed no evidence for a dosage effect, ie, responses were equivalent for low and high doses. CONCLUSIONS: This study does not support a high-dose anti-inflammatory action of nonsteroidal anti-inflammatory drugs or aspirin in AD. Potential mechanisms for the beneficial effects of these medications are discussed.  相似文献   
50.
A 4-week-old female infant presented with congestive heart failure, moderate mitral regurgitation, and an electrocardiographic pattern of anterolateral myocardial infarction. Angiography revealed normal coronary arteries and moderate mitral regurgitation. A single-catheter electrophysiology study confirmed the presence of an accessory atrioventricular conduction pathway.  相似文献   
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