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Background. Topical anesthetics are widely used to diminish the sensation of pain from various medical cutaneous procedures. Any topical agent that reduces the desired effect has clinical ramifications.
Materials and Methods. Topical 6% benzocaine cream was applied to both inner forearms of five persons and covered with a bandage. One of the arms was additionally treated simultaneously with 5% benzoyl peroxide. The areas were tested with a pinprick examination every 10 minutes for the ensuing hour.
Results. There was an estimated 75% increased perception of pain on the forearm to which benzoyl peroxide was applied in consort with the topical anesthetic at all examination times.
Conclusions. Benzoyl peroxide chemically reacts with topical anesthetics such as tetracaine, procaine, pramoxine, prilocaine, and lidocaine, causing a significant reduction in their numbing effect. Clinically, make sure that the skin area to be topically anesthetized is devoid of any previous treatment with benzoyl peroxide or insist that the skin is thoroughly washed prior to application of the anesthetic.
CRAIG G. BURKHART, MPH, MD, AND CRAIG N. BURKHART, MSBS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS.  相似文献   
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The production of phonological features of African American English (AAE) was examined for 64 typically developing African American children in the 2nd through the 5th grade. Students read aloud passages written in Standard American English. Sixty of the students read the passages using AAE, and 8 different phonological features were represented in their readings. Phonological features were more frequent than morphosyntactic features. The findings as a whole support use of the taxonomy developed for this investigation in characterizing the phonological features of child AAE.  相似文献   
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OBJECTIVE: To characterize dementia-induced changes in visual art production. BACKGROUND: Although case studies show altered visual artistic production in some patients with neurodegenerative disease, no case-controlled studies have quantified this phenomenon across groups of patients. METHOD: Forty-nine subjects [18 Alzheimer disease, 9 frontotemporal dementia (FTD), 9 semantic dementia (SD), 15 healthy older controls (NC)] underwent formal neuropsychologic testing of visuospatial, perceptual, and creative functioning, and produced 4 drawings. Subjective elements of drawings were rated by an expert panel that was blind to diagnosis. RESULTS: Despite equal performance on standard visuospatial tests, dementia groups produced distinct patterns of artistic features that were significantly different from NCs. FTDs used more disordered composition and less active mark-making (P<0.05). Both FTDs and SDs drawings were rated as more bizarre and demonstrated more facial distortion than NCs (P<0.05). Also, SDs drastically failed a standardized test of divergent creativity. Alzheimer disease artwork was more similar to controls than to FTDs or SDs, but showed a more muted color palette (P<0.05) and trends toward including fewer details, less ordered compositions, and occasional facial distortion. CONCLUSIONS: These group differences in artistic style likely resulted from disease-specific focal neurodegeneration, and elucidate the contributions of particular brain regions to the production of visual art.  相似文献   
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Research evidence that corticotropin-releasing factor (CRF) plays a role in the pathophysiology of major depressive disorder (MDD) has accumulated over the past 20 years. The elevation of lumbar cerebrospinal fluid (CSF) concentrations of CRF decreased responsiveness of pituitary CRF receptors to challenge with synthetic CRF, and increased levels of serum cortisol in MDD subjects support the hypothesis that CRF is chronically hypersecreted in at least the endocrine circuits of the hypothalamic-pituitary-adrenal (HPA) axis and may also involve other CRF brain circuits mediating emotional responses and/or arousal. One such circuit includes the excitatory CRF input to the locus coeruleus (LC), the major source of norepinephrine in the brain. Furthermore, there are now reports of decreased levels of CRF in lumbar CSF from MDD patients after symptom relief from chronic treatment with antidepressant drugs or electroconvulsive therapy. Whether this normalization reflects therapeutic effects on both endocrine- and limbic-associated CRF circuits has not yet been effectively addressed. In this brief report, we describe increased concentrations of CRF-like immunoreactivity in micropunches of post-mortem LC from subjects with MDD symptoms as established by retrospective psychiatric diagnosis compared to nondepressed subjects matched for age and sex.  相似文献   
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Abstract. Medical and social problems related to alcohol use are frequently seen in the ED. Often, the tempo of emergency medicine practice seems to preclude assessment beyond that required by the acute complaint. However, detection of ED patients with alcohol problems can occur using brief screening tools. This article was developed by members of the SAEM Substance Abuse Task Force, and describes screening tools that have been used successfully to identify atrisk and dependent drinkers. Their brevity, reproducibility, and accuracy vary somewhat, but screening can be realistically performed in the busy ED setting. The early detection of patients with alcohol problems would provide the opportunity for early intervention, and may reduce subsequent morbidity and mortality in this patient population.  相似文献   
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