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41.
David C. Cone MD Susan M. Nedza MD MBA James J. Augustine MD Steven J. Davidson MD MBA 《Academic emergency medicine》2002,9(11):1085-1090
This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference. 相似文献
42.
Naiquan Zheng Rafael F Escamilla Glenn S Fleisig Kevin E Wilk James R Andrews 《中华骨科杂志》2002,29(1):697-700
结果 髌股关节的压力与应力随膝关节屈曲角度的增加而升高,随膝关节屈曲角度的减小而降低(图3~8).不同膝关节屈曲角度下弓步变化和跨步变化的髌股关节压力见表1. 相似文献
43.
Nicole Lewis James Dollman Michael Dale 《Journal of Science and Medicine in Sport》2007,10(6):418-427
Rising youth obesity is a serious public health concern. There is a widespread view that declining physical activity is contributing to this trend. A total of 929 young South Australians (age = 9–15 years) were surveyed in 1985 and 2004 on usual physical activity in several contexts, including attitudes to physical activity. Eight of 10 South Australian schools participating in the 1985 Schools Health and Fitness Survey were revisited in 2004. Comparisons were made on: organised sport, active transport, physical education (PE), playground activity, vigorous physical activity (VPA), total leisure-time physical activity (LTPA), and attitudes to PE and school sport. The questionnaire and method of administration were identical in both surveys. There were no differences between surveys in club and school sport participation, walking to school, and reported enjoyment of PE and school sport. In 2004 fewer children rode to school, but PE classes were more frequent. The percentage of children who ‘sit and talk’ during school breaks had increased, with a decreased percentage of older girls who ‘run around’ during school breaks. There was a significantly higher LTPA in MET.min in 2004 for boys, which was particularly evident at higher percentiles. There were no changes in mean or distribution of LTPA for the whole sample or girls. The percentage of respondents reporting ≥3 bouts of VPA in the previous week rose from 51% (1985) to 76% (2004). There is no consistent evidence of declining physical activity among South Australian youth. It is apparent that physical activity in some contexts has declined, while in other contexts levels are the same or higher than in 1985. This underscores the complex nature of physical activity and the influences on this behaviour. 相似文献
44.
OBJECTIVE: Cancer Care Ontario has recommended a population-based colorectal cancer (CRC) screening program using fecal occult blood testing. Patients who test positive should undergo further investigation, preferably colonoscopy. So far, no studies have been performed to quantify the costs or demands on the health care system at the community level. The number of consultations, colonoscopies and polypectomies, and the corresponding direct medical costs generated by the CRC screening program, between 2006 and 2015 in London, Ontario, were estimated using a decision analysis model in comparison with the population health model. METHODS: A faxed survey study was conducted to examine the current CRC screening practice among family physicians in London. Data from the survey and randomized studies were applied to a decision analysis model, which simulated the steps involved in population-based biennial and annual CRC screening between 2006 and 2015. The number of consultations, colonoscopies and polypectomies, and their associated costs were calculated. RESULTS: For a cohort population of 140,000, between 50 and 74 years of age, in 2006 to 2015, it is estimated that an average of 412 consultations, 463 colonoscopies and 174 polypectomies will be performed per 100,000 screen eligible population per year in biennial screening, and double in annual screening, reflecting an average of 8.7% or 17.6% increase annually in outpatient colonoscopies, respectively, compared with 2003. A mean of $285,000 or $562,000 per year would be required to support the extra consultation and endoscopic procedures generated by the biennial or annual screening. CONCLUSION: Population-based fecal occult blood testing screening for CRC appears to be a manageable strategy if a modest increase in endoscopic resources is allocated. 相似文献
45.
Characterization of gp 50, a major glycoprotein present in rat brain synaptic membranes, with a monoclonal antibody 总被引:4,自引:0,他引:4
Philip W. Beesley Toni Paladino Claude Gravel Richard A. Hawkes James W. Gurd 《Brain research》1987,408(1-2):65-78
Several cell lines secreting monoclonal antibodies (Mabs) against a major forebrain synaptic membrane (SM) glycoprotein, gp 50, have been raised. Western blots show that the Mabs react with a polypeptide doublet of Mrs 49 and 45 kDa. These polypeptides exist solely in a concanavalin A (Con A) binding form. Removal of the Con A receptors by digestion with endo-beta-N-acetylglucosaminidase H (endo H) lowers the Mrs of the glycoprotein doublet to 36.5 and 34 kDa. Western blots of 2D polyacrylamide gels indicate that gp 50 exists in several isoforms. Solid phase radioimmunoassay (RIA) and Western blots of brain subcellular fractions show the antigenic material to be concentrated in the SM fraction, but to be present in much lower amounts in synaptic junctions and postsynaptic densities. Gp 50 appears to be brain specific. Regional distribution studies show that it is present in all brain regions but is two-fold concentrated in cerebellum, brainstem and midbrain compared to forebrain. Immunocytochemical studies of several brain regions show that gp 50-like immunoreactivity is neuron specific and is concentrated in selected neuronal species, particularly granule cells. In both cerebellar and hippocampal granule cells gp 50-like immunoreactivity is localized in the perikarya and primary dendrites. Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope. The results are discussed in terms of the molecular properties of gp 50 and its subcellular localization in brain tissue. 相似文献
46.
47.
Dnyanesh N Tipre James J Fox Daniel P Holt Gilbert Green Jianhua Yu Martin Pomper Robert F Dannals Frank M Bengel 《Journal of nuclear medicine》2008,49(7):1189-1195
The sympathetic nervous system of the heart plays a key role in the pathophysiology of various cardiac diseases. Small-animal models are valuable for obtaining further insight into mechanisms of cardiac disease and therapy. To determine the translational potential of cardiac neuronal imaging from rodents to humans, we characterized the rat sympathetic nervous system using 3 radiotracers that reflect different subcellular mechanisms: (11)C-meta-hydroxyephedrine (HED), a tracer of neuronal transport showing stable uptake and no washout in healthy humans; (11)C-phenylephrine (PHEN), a tracer of vesicular leakage and intraneuronal metabolic degradation with initial uptake and subsequent washout in humans; and (11)C-epinephrine (EPI), a tracer of vesicular storage with stable uptake and no washout in humans. METHODS: We used a small-animal PET system to study healthy male Wistar rats at baseline, after desipramine (DMI) pretreatment (DMI block), and with DMI injection 15 min after tracer delivery (DMI chase). The rats were kept under general isoflurane anesthesia while dynamic emission scans of the heart were recorded for 60 min after radiotracer injection. A myocardial retention index was determined by normalizing uptake at 40 min to the integral under the arterial input curve. Washout rates were determined by monoexponential fitting of myocardial time-activity curves. RESULTS: At baseline, HED showed high myocardial uptake and sustained retention, EPI showed moderate uptake and significant biphasic washout, and PHEN showed moderate uptake and monoexponential washout. The average (+/- SD) left ventricular retention index for HED, PHEN, and EPI was 7.38% +/- 0.82%/min, 3.43% +/- 0.45%/min, and 4.24% +/- 0.59%/min, respectively; the washout rate for HED, PHEN, and EPI was 0.13% +/- 0.23%/min, 1.13% +/- 0.35%/min, and 0.50% +/- 0.24%/min, respectively. The DMI chase resulted in increased washout only for HED. DMI block decreased myocardial uptake of all tracers by less than 90%. CONCLUSION: Kinetic profiles of HED in the rat myocardium were similar to those of HED in humans, suggesting comparable neuronal transport density. Unlike in humans, however, significant washout of EPI and faster washout of PHEN were encountered, consistent with high intraneuronal metabolic activity, high catecholamine turnover, and reduced vesicular storage. This evidence of increased neuronal activity in rodents has implications for translational studies of cardiac neuronal biology in humans. 相似文献
48.
49.
The Institute of Medicine distinguishes between programs based on who is targeted: the entire population (universal), those
at risk (selective), or persons exhibiting the early stages of use or related problem behavior (indicated). Evaluations suggest
that although universal programs can be effective in reducing and preventing substance use, selective and indicated programs
are both more effective and have greater cost-benefit ratios. This paper tests these assumptions by comparing the impact of
these program types in reducing and preventing substance use at the individual level (i.e., those exposed to intervention
services) and in the population (i.e., those exposed and not exposed to intervention services). A meta-analysis was performed
on 43 studies of 25 programs to examine program comparability across IOM categories. When examining unadjusted effect sizes
at the individual level, universal programs were modestly more successful in reducing tobacco use, but selective and indicated
programs were modestly more successful in reducing alcohol and marijuana use. When adjusted to the population level, the average
effect sizes for selective and indicated programs were reduced by approximately half. At the population level, universal programs
were more successful in reducing tobacco and marijuana use and selective and indicated programs were more successful in reducing
alcohol use. Editors’ Strategic Implications: The authors’ focus on the public health value of a prevention strategy is compelling and provides a model for analyses of
other strategies and content areas. 相似文献
50.
Harold C. Lyon Jr. James C. Healy James R. Bell Joseph F. O'Donnell Edward K. Shultz Robert S. Wigton Frank Hirai J. Robert Beck 《Journal of medical systems》1991,15(2):117-132
Richard E. Clark in his widely published comprehensive studies and meta-analyses of the literature on computer assisted instruction (CAI) has decried the lack of carefully controlled research, challenging almost every study which shows the computer-based intervention to result in significant post-test proficiency gains over a non-computer-based intervention. We report on a randomized study in a medical school setting where the usual confounders found by Clark to plague most research, were carefully controlled. PlanAlyzer is a microcomputer-based, self-paced, case-based, event-driven system for medical education which was developed and used in carefully controlled trials in a second year medical school curriculum to test the hypothesis that students with access to the interactive programs could integrate their didactic knowledge more effectively and/or efficiently than with access only to traditional textual “nonintelligent” materials. PlanAlyzer presents cases, elicits and critiques a student's approach to the diagnosis of two common medical disorders: anemias and chest pain. PlanAlyzer uses text, hypertext, images and critiquing theory. Students were randomized, one half becoming the experimental group who received the interactive PlanAlyzer cases in anemia, the other half becoming the controls who received the exact same content material in a text format. Later in each year there was a crossover, the controls becoming the experimentals for a similar intervention with the cardiology PlanAlyzer cases. Preliminary results at the end of the first two full trials shows that the programs have achieved most of the proposed instructional objectives, plus some significant efficiency and economy gains. 96 faculty hours of classroom time were saved by using PlanAlyzer in their place, while maintaining high student achievement. In terms of student proficiency and efficiency, the 328 students in the trials over two years were able to accomplish the project's instructional objectives, and the experimentals accomplished this in 43% less time than the controls, achieving the same level of mastery. However, in spite of these significant efficiency findings, there have been no significant proficiency differences (as measured by current factual and higher order multiple choice post-tests) between the experimental and control groups. Very careful controls were used to avoid what Clark has found to be the most common confounders of CAI research. Accordingly, this research proved Clark's rival hypothesis, that the computer, in itself, does not appear to contribute to proficiency gains, at least as measured by our limited post-testing. Clark's position is that the computer is primarily a vehicle—as is either a pill or a hypodermic needle for delivering a drug. The hypodermic needle can deliver the drug more efficiently than can the pill, (as can the computer deliver the subject matter content more efficiently, as our research indicates), but the same content is delivered. At the same time, we proved our own hypothesis, as far as efficiency gains resulting from the computer are concerned. However, going beyond Clark's research, we may be teaching processes both more effectively and efficiently with the computer (experience in problem-solving or clinical reasoning and pattern recognition) which our current post-tests do not adequately measure. Our on-going research suggests additional inquiry in several areas: better evaluation instruments to measure the clinical reasoning skills PlanAlyzer was designed to teach; the addition of more advanced cases to determine if this might transform efficiency gains of the computer group into proficiency gains; the addition of enhanced graphic decision support tools and other pedagogical enhancements including cognitive feedback to strengthen PlanAlyzer's power to teach complex concepts of medical decision-making. 相似文献