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51.
Subsets of nucleus accumbens (NAc) neurons process information about operant responses for drugs as well as natural rewards (food and water) by excitations and inhibitions in firing rate time-locked to the operant response. The degree to which ensembles of neurons exhibit similar firing patterns when encoding cues and operant responses across different reinforcer conditions will provide critical information regarding the functional organization of this nucleus. The present experiment evaluated the relative contribution of subsets of accumbens neurons that encode distinct features of lever press responding for ethanol vs. water. Electrophysiological recordings (n = 153 neurons) were made in the accumbens of rats trained on concurrent reinforcement schedules for ethanol and water throughout a self-administration session. During operant responding, 52% of neurons exhibited patterned discharges characterized by significant increases or decreases in firing rate of +/- 1 s relative to lever presses for ethanol and/or water. Of these phasic cells, 85% discriminated between presses for ethanol and water (i.e. exhibited firing patterns unique to one reinforcer type), while 15% exhibited identical firing patterns relative to lever presses for both reinforcers. Notably, the data revealed that both high ethanol preference and spatially distinct lever positions contributed to the reinforcer specificity. Together, these data demonstrate that subsets of NAc neurons encode conditioned and instrumental aspects of ethanol vs. water reinforcement in well-trained rats, and that reinforcer preference and spatial cues are important components of this differential information processing. 相似文献
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Croft DR Sotir MJ Williams CJ Kazmierczak JJ Wegner MV Rausch D Graham MB Foldy SL Wolters M Damon IK Karem KL Davis JP 《Emerging infectious diseases》2007,13(8):1150-1157
We determined factors associated with occupational transmission in Wisconsin during the 2003 outbreak of prairie dog--associated monkeypox virus infections. Our investigation included active contact surveillance, exposure-related interviews, and a veterinary facility cohort study. We identified 19 confirmed, 5 probable, and 3 suspected cases. Rash, headache, sweats, and fever were reported by > 80% of patients. Occupationally transmitted infections occurred in 12 veterinary staff, 2 pet store employees, and 2 animal distributors. The following were associated with illness: working directly with animal care (p = 0.002), being involved in prairie dog examination, caring for an animal within 6 feet of an ill prairie dog (p = 0.03), feeding an ill prairie dog (p = 0.002), and using an antihistamine (p = 0.04). Having never handled an ill prairie dog (p = 0.004) was protective. Veterinary staff used personal protective equipment sporadically. Our findings underscore the importance of standard veterinary infection-control guidelines. 相似文献
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STUDY OBJECTIVES: To measure the accessibility and quality of currently available asthma education World Wide Web sites using the following criteria: accessibility by readability, language, and download time; information quality based on inclusion of core educational concepts and compliance with Health On the Net (HON) principles; and utilization of innovative technology. DESIGN: Objective evaluation of 145 Web sites. Measurements and results: Four search engines or directories (Yahoo, HON, Alta Vista, and Healthfinder) were searched for "asthma, patient information." A maximum of 50 Web sites from each search engine or directory was evaluated. Only 90 of the 145 Web sites actually contained asthma educational material. The mean (+/- SD) time necessary to open each Web site on a 28.800-bits-per-second modem was 33.6 ( +/- 36.6) s. The mean number of graphics on the Web sites was 24.6 ( +/- 30.2) files per page. The educational material required a mean reading level beyond the 10th grade. Only nine Web sites contained multilingual asthma education material. The mean number of HON principles with which the Web sites conformed was 6.3 ( +/- 1.0) of 8 principles; 14 Web sites conformed to all the HON criteria. The average Web site contained 4.9 (+/- 2.5) of 8 core asthma educational concepts, and only 20 Web sites contained all 8 educational concepts. Very few Web sites utilized innovative educational technology. CONCLUSIONS: While patient asthma education Web sites are common, asthma educational material contains many accessibility barriers, is highly variable in quality and content, and takes little innovative use of technology. Patient educational material currently available on the World Wide Web fails to meet the information needs of patients. 相似文献
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Dhanunjaya Lakkireddy Yeruva Madhu Reddy Luigi Di Biase Ajay Vallakati Moussa C. Mansour Pasquale Santangeli Sandeep Gangireddy Vijay Swarup Fadi Chalhoub Donita Atkins Sudharani Bommana Atul Verma Javier E. Sanchez J. David Burkhardt Conor D. Barrett Salwa Baheiry Jeremy Ruskin Vivek Reddy Andrea Natale 《Journal of the American College of Cardiology》2014
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MaryAnn Tapper Strawhacker Jeri K Gustafson Marilyn J Kinne Donita Little 《The Journal of school nursing》2003,19(2):111-118
In response to data from the initial survey published in October 2001, interventions were developed to increase vision screening knowledge and promote use of the Iowa Vision Screening Program Guidelines. The purpose of this evaluation was to measure differences in practice after interventions, including attendance at a half-day workshop and practice session. Results of the study indicate that participants of the workshop and practice session were more likely to conduct yearly distance and near vision, and depth perception screening. In addition, they were more likely to use the recommended screening instruments for distance and near vision, and depth perception. They were also much more likely to use recommended referral criteria for all types of screening and to have changed some aspect of their vision screening practice in the past year. Results are presented with implications for school nursing practice. 相似文献
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Storbeck KH Swart P Africander D Conradie R Louw R Swart AC 《Molecular and cellular endocrinology》2011,336(1-2):92-101
The metabolism of progesterone (PROG) by cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17A1) results in the formation of both 17α-hydroxyprogesterone (17-OHPROG) and 16α-hydroxyprogesterone (16-OHPROG) in humans. Unlike 17-OHPROG, 16-OHPROG is not metabolised further in steroidogenic tissue. While this metabolite can be readily detected in serum and urine, its physiological role remains unclear. This paper reviews the production of 16-OHPROG by human CYP17A1 by providing insight into the catalysis of PROG by CYP17A1 and highlights the role of Ala105 in the 16α-hydroxylation reaction. As 16-OHPROG has been putatively linked to reproductive function, we investigated the interaction of this steroid metabolite with both isoforms of the human progesterone receptor (hPR). We show for the first time that 16-OHPROG can bind to both hPR-A and hPR-B and act as an agonist for both receptors. 相似文献