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As the body of medical literature continues to expand, physicians must develop the necessary skills to keep up with the vast amount of information available. The journal club provides a forum to allow residents to remain current with the literature while also teaching them the methods to evaluate it critically. Those readers wishing to start a journal club or revive an existing one should begin by designating a leader and defining the conference goals. Emphasizing the importance of this conference in the educational process while allowing it to be structured to optimise resident interest and attendance will help to ensure its success. Periodic evaluation of this conference will allow the organisers to assess the concordance of the resident''s goals with those of the faculty. Formal evaluation will also provide an objective assessment of the knowledge gained by the house-staff through participation in journal club.  相似文献   
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OBJECTIVE: We investigated whether newborns respond differently to novel and deviant sounds during quiet sleep. METHODS: Twelve healthy neonates were presented with a three-stimulus oddball paradigm, consisting of frequent standard (76%), infrequent deviant (12%), and infrequent novel stimuli (12%). The standards and deviants were counterbalanced between the newborns and consisted of 500 and 750 Hz tones with two upper harmonics. The novel stimuli contained animal, human, and mechanical sounds. All stimuli had a duration of 300 ms and the stimulus onset asynchrony was 1s. Evoked magnetic responses during quiet sleep were recorded and averaged offline. RESULTS: Two deflections peaking at 345 and 615 ms after stimulus onset were observed in the evoked responses of most of the newborns. The first deflection was larger to novel and deviant stimuli than to the standard and, furthermore, larger to novel than to deviant stimuli. The second deflection was larger to novel and deviant stimuli than to standards, but did not differ between the novels and deviants. CONCLUSIONS: The two deflections found in the present study reflect different mechanisms of auditory change detection and discriminative processes. SIGNIFICANCE: The early brain indicators of novelty detection may be crucial in assessing the normal and abnormal cortical function in newborns. Further, studying evoked magnetic fields to complex auditory stimulation in healthy newborns is needed for studying the newborns at-risk for cognitive or language problems.  相似文献   
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BACKGROUND: Airway inflammation is a characteristic feature of bronchial asthma. Previous studies have shown an increased local inflammatory activity in the airway mucosa of asthma patients. OBJECTIVES: To analyze the association of asthma with three sensitive markers of systemic inflammation, C-reactive protein, serum amyloid-A (SAA), and plasma fibrinogen. METHODS: A cross-sectional, population-based study including 1,513 Finnish men aged 45 to 74 years, who participated in a chronic disease risk factor survey in 1997. Of the participating men, 97 were classified as asthma patients. The odds ratios of asthma were analyzed by quartile of each inflammation marker. RESULTS: In logistic regression models the age-adjusted odds ratios (second, third, and fourth quartile as compared with the first quartile) of asthma increased gradually with increasing quartile of C-reactive protein (1.28, 1.19, 1.96, P for trend = 0.039), SAA (1.20, 3.00, 3.49, P for trend < 0.001), and fibrinogen (1.22, 1.79, 3.16, P for trend < 0.001). The associations were independent of smoking. Further adjustment for waist-to-hip ratio, a marker of central obesity, and symptoms of chronic bronchitis weakened the observed association, but the increasing trend in the association of SAA and fibrinogen with asthma remained highly significant. CONCLUSIONS: Sensitive markers of systemic inflammation, particularly SAA and fibrinogen, were positively and significantly associated with asthma prevalence. These findings support the hypothesis that not only local, but also systemic, inflammation exist in bronchial asthma.  相似文献   
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A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc.  相似文献   
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A 34-years-old floor-layer developed optic neuropathy and motor neuron disease after being accidentally exposed to a solvent mixture containing methanol and other substances. Optic neuropathy is a complication of methanol poisoning, but the onset of a motor neuron disorder resembling amyotrophic lateral sclerosis after the exposure to these substances has not been previously described. The temporal onset of the clinical symptoms, biological plausibility, young age of the patient and absence of neurological disorders in the family history raises suspicion of a possible causative relationship.  相似文献   
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It has been reported that treatment with L-carnitine at a daily dose of 3 g orally may cause a rise in platelet aggregation and serum triglyceride concentration in hemodialyzed patients. The present double-blind cross-over study has been performed to evaluate the influence of L-carnitine when compared with placebo on platelet aggregation and plasma concentrations of various factors involved in platelet activation. In addition, the concentration of triglycerides, cholesterol and HDL-cholesterol has been evaluated. 18 uremic patients on maintenance hemodialysis for at least 1 year were randomly allocated either to a control group receiving placebo or to a group treated with L-carnitine. Statistical analysis performed by means of ANOVA did not show any significant change in the serum concentration of cholesterol, HDL-cholesterol and triglycerides. Furthermore, platelet aggregation tests (performed with adenosine 5'-diphosphate, epinephrine, thrombin and collagen) and plasma beta-thromboglobulin concentration did not show any statistically significant difference. In addition, the plasma concentration of several coagulation markers, such as factor VIIIc, antithrombin III, alpha 2-antiplasmin, and fibrinopeptide A, did not show any significant variation. The results suggest that under our experimental conditions L-carnitine neither increases the risk of thromboembolism nor alters the serum lipid content in uremic patients on chronic hemodialysis.  相似文献   
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The detection of a change in a face stimulus was studied in an oddball paradigm. Event-related potentials (ERPs) and MEG responses to face stimuli were recorded in four conditions: 1) happy standard, neutral deviant; 2) neutral standard, neutral deviant; 3) inverted happy standard, inverted neutral deviant; 4) inverted neutral standard, inverted neutral deviant. In all conditions, the target was a face with glasses. Neutral deviants elicited a negative deflection (with a maximum around 280 ms) in ERP and MEG responses, an effect similar to auditory mismatch negativity. Face inversion diminished deviance-related negativity, implying an important role of face recognition in the observed effect. Emotional content and larger physical differences between stimuli in conditions 1 and 3 compared to conditions 2 and 4 did not show statistically significant effect on the neutral-deviant-related negativity.  相似文献   
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