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Rhesus monkeys with neonatal damage to either the medial temporal lobe or the inferior temporal cortical area TE, and their normal controls, were reassessed in visual habit formation (24-hour intertrial interval task) and visual recognition (delayed nonmatching to sample [DNMS]) at 4–5 years of age and then tested on tactile and spatial DNMS. Results on the two visual tasks were the same as those obtained when the monkeys were under 1 year of age. Specifically, early medial temporal lesions, like late lesions, left habit formation intact but severely impaired recognition memory. Furthermore, the memory deficit extended to the tactile and spatial modalities. By contrast, early damage to TE, unlike late damage to it, yielded only mild deficits on both visual tasks and had no effect on tactile or spatial DNMS. Compensatory mechanisms that promote substantial and permanent recovery thus appear to be available after neonatal TE lesions but not after neonatal medial temporal lesions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The clinical use of anticancer anthracyclines is limited by the development of a distinctive and life-threatening form of cardiomyopathy upon chronic treatment. Commonly accepted mechanistic hypotheses have assigned a pivotal role to iron, which would act as a catalyst for free radical reactions and oxidative stress. Although perhaps involved in acute aspects of anthracycline cardiotoxicity, the role of free radical-based mechanisms in long-term effects has been challenged on both experimental and clinical grounds, and alternative hypotheses independent of iron and free radicals have flourished. More recently, studies of the role of C-13 hydroxy metabolites of anthracyclines have provided new perspectives on the role of iron in the cardiotoxicity of these drugs, showing that such metabolites can impair intracellular iron handling and homeostasis. The present review applies a multisided approach to the critical evaluation of various hypotheses proposed over the last decade for the role of iron in anthracycline-induced cardiotoxicity. The main goal of the authors is to build a unifying pattern that would both account for hitherto unexplained experimental observations and help design novel and more rational strategies toward a much-needed improvement in the therapeutic index of anthracyclines.  相似文献   

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We report that long-term selective immunoglobulin G immunoadsorption by protein A (PAI) improved seizure frequency and neuropsychological deficits in a 16-year-old patient with severe treatment-resistant Rasmussen's encephalitis (RE). Clinical improvement correlated with reduction of antiglutamate receptor 3 antibodies. The efficacy of PAI in our patient supports the autoimmune hypothesis of RE and suggests its application to avoid, or at least delay, functional hemispherectomy in selected cases.  相似文献   

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Only scant information is available on the long-term consequences to respiratory health of treatment with bronchodilators and oral corticosteroids. In the present study, we aimed to gain more information about these consequences. We examined 712 men working in the Paris area, by means of a subjective assessment of whether their respiratory health worsened or improved from 1960 to 1972, the decline in forced expiratory volume in one second (FEV1) over this time-period, and mortality from 1972 to 1992, in relation to respiratory therapy dispensed during a 2 year period in 1970-1971, as recorded in social security reimbursement records. As expected, subjects with respiratory symptoms or airflow limitation were more likely to have been prescribed respiratory therapy. After accounting for the effect of lung function level and smoking, subjects dispensed inhaled beta-agonists were likely to feel their condition had worsened and had a greater decline in FEV1 from 1960 to 1972. Among subjects with airflow limitation who reported asthma or persistent wheeze, having been dispensed oral corticosteroids on an intermittent basis was associated with improved survival (relative risk (RR) 0.32; 95% confidence interval (95% CI): 0.10-0.91) after adjusting for FEV1 level and smoking category. Our results add to the evidence that regular use of beta-agonist bronchodilators may be associated with adverse effects on respiratory health, whilst intermittent use of corticosteroids may be of long-term benefit.  相似文献   

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The resistance to 14 antiseptic-disinfectant and dye compounds of 208 strains of Listeria (132 L. monocytogenes, 63 L. innocua, 8 L. seeligeri, 1 L. ivanovii, 1 L. welshimeri, and 3 Listeria spp.) was tested by the agar-dilution procedure. The Listeria strains were isolated from different varieties of foods, environments of cheese dairies, humans, and wild birds. A total of 14 (6.7%) Listeria strains (12 L. monocytogenes and 2 L. innocua) were resistant to benzalkonium chloride, hexamidine diisethionate, and ethidium bromide. This multiple resistance was observed more frequently from strains of Listeria spp. detected on carcasses of poultry (47%) than strains isolated from human listeriosis cases or carriers (11.5%), red meats (10%), cheeses (5.4%), wild birds (0.9%), and environments of cheese dairies (0%). Among resistant strains, 10 groups of strains (71.5%) were differentiated by serogroup, phage typing, and sensitivity or resistance to cadmium. Extrachromosomal DNA was found in all resistant strains and was transferred at a high frequency among Listeria spp. (8.7 x 10(-6) to 1 x 10(-3) transconjugant CFUs per one donor CFU). These resistances were also transferable between L. monocytogenes and Staphylococcus aureus with similar transfer frequencies (7.8 x 10(-6) to 1 x 10(-4) and between strains of Staphylococcus aureus with similar transfer frequencies from 8 x 10(-7) to 3.3 x 10(-6). These results suggest that emergence of this multiple resistance in Listeria spp. could be due to acquisition of a replicon originating in staphylocci.  相似文献   

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The effects of pinacidil and nimodipine on endothelin-1-induced contractions in isolated cerebral arteries with and without endothelium were compared. The sensitivity to endothelin-1 was increased (0.5 log units) in the rabbit basilar artery after removal of the endothelium. The nitric oxide synthase inhibitor N omega-nitro-L-arginine (0.1 mM) also increased the sensitivity to endothelin-1 (0.6 log units) in basilar arteries with endothelium, whereas N omega-nitro-D-arginine (0.1 mM) and indomethacin (3 microM) had no effect, indicating that withdrawal of endothelium-derived nitric oxide may account for the enhancement of the endothelin-1-induced contraction after endothelial denudation. Pinacidil (1 microM) shifted the concentration-response curve for endothelin-1 to the right without affecting the maximal response in arteries without endothelium, but had no effect on the endothelin-1-induced contraction in vessels with endothelium. Nimodipine (1 microM) reduced the maximal endothelin-1-induced contraction by approximately 50% in both the presence and absence of endothelium, whereas the sensitivity to endothelin-1 was reduced only in vessels without endothelium. Incubation in "calcium-free" medium reduced the maximal endothelin-1-induced contraction by 69% and 80% in vessels with and without endothelium, respectively. In human pial arteries with endothelium, pinacidil did not affect the endothelin-1-induced contraction, whereas nimodipine and exposure to "calcium-free" solution reduced the maximal response by 31% and 74% respectively. The results show that, in the rabbit, pinacidil and to a lesser extent nimodipine preferentially act on cerebral arteries with disrupted endothelium, indicating that vasoactive factors liberated from the endothelium may modify the effect of a vasodilator.  相似文献   

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A total of 317 mandibular fracture patients treated and diagnosed at the Oulu University Hospital and at the Department of Oral and Maxillofacial Surgery, University of Oulu, Finland, between 1981 and 1990 were analyzed from patient files and radiographs. The mean number of mandibular fracture patients per year was 31.7 (range 21 and 45) and the mean age of the patients 31.3 years (range 4-78 years). The female:male ratio was 1:3.1. There seemed to be a tendency for decrease in the proportion of violence and traffic accidents as causes of mandibular fractures toward the end of the period concerned, reflecting partly the influence of mandatory use of safety belts and partly that the hospital in the northernmost part of Finland, where the consumption of alcohol is higher than in the province of Oulu, could treat all mandibular fractures itself during the last year studied thus decreasing the injuries caused by violence at the Oulu University Hospital. It was also noted that fewer fractures were caused at weekends than on weekdays during the latter years of the decade and that the proportion of male victims decreased except for the last year examined, 1990.  相似文献   

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Reviews the literature reporting lasting adverse psychological reactions to LSD, along with other relevant reports where LSD users were followed. Data indicate that the danger of long-lasting psychological damage is low when the drug is used by emotionally stable Ss in secure, controlled settings, but Ss with psychiatric disturbance, unstable personalities, and current crisis situations have experienced pathological behavior temporally related to drug ingestion. Adverse reactions were not reported in well-controlled studies with normal Ss, indicating the drug's relative safety for continued research. (67 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Four experiments were conducted to quantify the effect of performing a foveal discrimination task on sensitivity for a peripheral grating. The observer's primary task was to discriminate either the spatial frequency or orientation of successive foveal Gabor patches. On a third of the trials they also performed a secondary task to detect the presence of a near-threshold grating in the periphery. We find that sensitivity for detection of the peripheral grating depends on the similarity of the spatial frequencies and orientations between the foveal and peripheral stimuli. Importantly, sensitivity is also affected by which feature is being discriminated in the central task. Because the detectability of the peripheral grating is different when different features of the central stimuli are discriminated, we suggest that the effects on sensitivity are due to feature-specific attention and not simply to passive interactions between filters with similar tuning properties.  相似文献   

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241 children (approximately 10 yrs old) of 233 mothers who did or did not smoke during pregnancy were compared on 4 classes of variables: physical, intellectual, affective, and personal and social functioning. No statistically significant differences were found between the offspring of smokers and nonsmokers on these variables. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Objectives: To examine the longer term efficacies of exposure to UV photographs and photoaging information (e.g., wrinkles and age spots) for increasing sun protection intentions and behaviors of young adults. Design: Randomized controlled trial with 4- to 5-month and 12-month follow-ups. Main Outcome Measures: Participants' self-reported sun protection intentions assessed immediately after the interventions, and both self-reported sun protection behaviors and an objective assessment (via spectrophotometry) of skin color change measured at the end of summer (4-5 months following interventions) and 1 year following interventions. Results: Both interventions resulted in immediate positive effects on future sun protection intentions. Both interventions showed objective evidence of less skin darkening at the postsummer follow-up, with those in the photoaging information condition also reporting more sun protective behavior and continuing to show less skin darkening 1 year after intervention. There was also evidence that effects of photoaging information on subsequent skin color change were mediated by the earlier positive effect photoaging information had on participants' intentions to sun protect and their subsequent sun protection behaviors. Conclusions: UV photo and photoaging-information interventions each show promise as a brief and relatively inexpensive approach for motivating sun protection practices that may reduce skin cancer risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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