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91.
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   
92.
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   
93.
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   
94.
Abstract: Earlier work in this laboratory showed that amiodarone induces apoptosis in alveolar epithelial cells by a mechanism inhibitable by angiotensin system antagonists. A variety of recent studies suggests a critical role for alveolar epithelial cell apoptosis in the pathogenesis of lung fibrosis. On this basis we hypothesized that amiodarone‐induced alveolar epithelial cell apoptosis and lung fibrosis in vivo might be inhibitable by the angiotensin converting enzyme inhibitor captopril or the angiotensin receptor antagonist losartan. Amiodarone‐induced lung fibrosis was induced in male Wistar rats by oral adminstration over six months. Replicate groups of rats received captopril or losartan in addition to amiodarone. Apoptosis was detected by increased total lung activity of caspase 3 and in situ end labeling (ISEL) of fragmented DNA. Collagen was localized and quantitated by the picrosirius red technique. Alveolar epithelial cell apoptosis was detected in amiodarone‐treated animals as early as three weeks after the start of amiodarone administration; by six months exposure, the incidence of alveolar epithelial cell apoptosis was significantly reduced by coadministration of captopril or losartan. Alveolar wall collagen accumulation also was significantly attenuated by captopril (100%) or losartan (74%), but neither agent blunted the accumulation of alveolar macrophages evoked by amiodarone (5.3‐fold at 6 months). Lung neutrophil content was unchanged by amiodarone treatment for three weeks or six months. These results indicate that amiodarone induces alveolar epithelial cell apoptosis in vivo that is inhibitable by angiotensin antagonists. They also support the hypothesis that blockade of angiotensin formation or function attenuates amiodarone‐induced lung fibrosis irrespective of the severity of alveolitis.  相似文献   
95.
PURPOSE: In recent years, the incidence of cutaneous melanoma has increased more than that of any other cancer. Dacarbazine is considered the gold standard for treatment, having a response rate of 15% to 20%, but most responses are not sustained. Previously, we have shown that short exposure of primary cutaneous melanoma cells to dacarbazine resulted in the upregulation of interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF). The purpose of the present study was to determine how long-term exposure of melanoma cells to dacarbazine would affect their tumorigenic and metastatic potential in vivo. MATERIALS AND METHODS: The primary cutaneous melanoma cell lines SB2 and MeWo were repeatedly exposed in vitro to increasing concentrations of dacarbazine, and dacarbazine-resistant cell lines SB2-D and MeWo-D were selected and examined for their ability to grow and metastasize in nude mice. RESULTS: The dacarbazine-resistant cell lines SB2-D and MeWo-D exhibited increased tumor growth and metastatic behavior in vivo. This increase could be explained by the activation of RAF, MEK, and ERK, which led to the upregulation of IL-8 and VEGF. More IL-8, VEGF, matrix metalloproteinase-2 (MMP-2), and microvessel density (CD-31) were found in tumors produced by SB2-D and MeWo-D in vivo than in those produced by their parental counterparts. No mutations were observed in BRAF. CONCLUSION: Our results have significant clinical implications. Treatment of melanoma patients with dacarbazine could select for a more aggressive melanoma phenotype. We propose that combination treatment with anti-VEGF/IL-8 or MEK inhibitors may potentiate the therapeutic effects of dacarbazine.  相似文献   
96.
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   
97.
OBJECTIVE: To document adverse effects of anabolic-androgenic steroid (AAS) use in community-based users attending a medical clinic. DESIGN AND SETTING: Prospective recruitment, questionnaire-based interview, physical examination and investigations, with follow-up, of people who attended, anonymously, an inner-city hospital clinic established specifically to examine AAS use. PARTICIPANTS: 58 men, comprising 27 past AAS users, 14 present users and 17 potential users (who formed the control group). MAIN OUTCOME MEASURE: Clinical adverse effects and abnormal laboratory findings. RESULTS: Cyclical use of oral and intramuscular, human and veterinary AASs were reported. The most commonly reported source of AASs was friends (59%), gymnasiums (25%) and doctors (14%). The most common reported adverse effects were alterations in libido (61%), changes in mood (48%), reduced testis volume (46%) and acne (43%). Although mean systolic and diastolic blood pressure was not significantly different between groups, five present (29%), 10 past (37%) and one potential user (8%) were hypertensive. Gynaecomastia was found in 10 past users (37%; P<0.01 v. potential users), two present users (12%) and no potential users. Mean testis volume was significantly smaller in present users (18 mL; P<0.02) than in the other groups. Twenty past users (83%), eight present users (62%) and five potential users (71%) had abnormal liver function test results (P=0.5). After discussion of test results, only 11 participants (19%) reported they would not use AASs in the future. CONCLUSIONS: Adverse effects were reported by or detected in most of the AAS users who attended the clinic. Despite awareness of adverse consequences, most participants planned future use of AASs.  相似文献   
98.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective.  相似文献   
99.
The role of surgery in the intensive care unit (ICU) remains unclear. Although previously shown not to increase morbidity for patent ductus arteriosus ligation, Broviac catheter insertion, and recently, general neonatal and paediatric surgery, there remains a reluctance to operate on sick patients in the ICU (in-situ surgery, ISS). A retrospective study of 25 critically ill children and neonates who underwent ISS was performed. Surgery was aided by operating loupes and a high-intensity headlight. ISS was not associated with any morbidity, and although a 36% mortality occurred in this small series, in no case was this due to ISS. ISS avoids the risks of transfer to the operating theatre and the potential delays in theatre access. Our results suggest that ISS in a tertiary-level paediatric surgical hospital is safe and does not impact adversely on clinical outcome. Accepted: 7 January 1998  相似文献   
100.
Radioimmunotherapy (RIT) is currently limited by toxicity to normal tissues as a result of prolonged circulating radioantibody in the blood. In this study, the use of a clearing antibody was investigated (second antibody) in an attempt to reduce blood background levels of [90Y]A5B7 immunoglobulin G (IgG) activity, and, therefore, improve the therapeutic tumour-blood ratio in nude mice bearing human colorectal tumour xenografts. The second antibody was raised against the 12N4 macrocycle group used for chelation of 90Y, and is, thus, applicable to any anti-tumour antibody labelled with this methodology. Second antibody was administered 18, 24 or 48 h after radiolabelled antibody injection and produced up to a tenfold reduction in blood levels and a tenfold improvement in tumour-blood ratios. This has the advantage of reducing the risk of myelotoxicity caused by prolonged retention of activity in the blood. For all normal tissues, there was a similar or slightly lower uptake of [90Y]IgG with second antibody clearance, apart from a transient rise in liver activity due to complexes of primary and secondary antibody clearing via the liver. As a result of clearance of [90Y]IgG from the blood pool, there was an associated fall in the amount of antibody at the tumour site (up to 3.3-fold) at later time points for mice injected with second antibody. However, despite this, tumour-blood ratios remained superior to the control group at these later time points. Estimated dosimetry evaluation revealed that total dose to normal tissues, blood and tumour was lower than for the non-clearance group. Surprisingly, however, there was little improvement in total estimated tumour-blood dose ratio over the time period studied. This was probably because the majority of the dose was delivered to both the blood and tumour within the first 24 h after administration of [90Y]IgG, so that giving the clearing agent after this time did not produce a large difference in total estimated dose. The anti-macrocycle second antibody proved to be a successful clearing agent and could potentially be applied to any anti-tumour antibody coupled with the 12N4 macrocycle. In the light of the estimated dosimetry results described here, it would probably be most useful given at earlier time points (i.e. before 18 h after injection of primary antibody) to produce an improved tumour-blood ratio of total dose. Development of this strategy may allow higher levels of activity to be administered for RIT, and repeated dosing regimens.  相似文献   
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