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101.
A diagnosis of Hirschsprung's disease should be considered in children with constipation. An accurate neonatal history of bowel function and testing of anorectal pressure responses will aid the diagnosis. In the period 1971-75 inclusive, 140 children, aged 6 months to 14 years, were investigated by anorectal manometry. 26 showed a failed inhibition response to rectal dilatation, suggesting Hirschsprung's disease and were treated by anorectal myectomy. In 24 the disease was confirmed histologically. Two specimens were diagnostically unsuitable. 4 required repeat myectomies, and 3 anterior resection. At follow-up all had normal bowel movements without soiling.  相似文献   
102.
BACKGROUND: Studies have provided little evidence that critical appraisal skills improve with focused courses. However, outcome measures in these studies have been questionable. The goal of this study was to develop a feasible, reliable, and valid assessment of critical appraisal skills. METHODS: Forty-four surgery residents read three articles and then responded to short answer questions and provided 7-point ratings regarding various methodological aspects of each article. Reliability and validity of the examination were assessed. RESULTS: The mean score was 52.4% (SD 8.6%). Internal consistency of the 55-question examination was 0.77. Interrater reliability of clinician markers was 0.91. Mean score for residents with more intensive critical appraisal training was significantly higher than for those with little or no training (56.6% versus 49.3%, t(35) = 2.31, P = 0.02), suggesting construct validity. CONCLUSIONS: This examination has promising psychometric properties, and may be useful in evaluating critical appraisal curricula.  相似文献   
103.
BACKGROUND: The effectiveness of interventions for developing critical appraisal skills in practicing physicians has not been studied, despite the documented importance of reading the literature in caring for patients and in continuing professional development. The objective of this study was to evaluate whether an Internet-based intervention would lead to enhanced critical appraisal skills in practicing surgeons. METHODS: General surgeons who agreed to participate were randomized into 2 groups. The intervention was a curriculum in critical appraisal skills that included a clinical and methodologic article, a listserve discussion, and clinical and methodologic critiques. The control group received only the clinical articles. The primary outcome measure was a previously validated 2-hour test of critical appraisal. RESULTS: Of the 55 surgeons who completed the examination, subjects in the intervention group performed better on the test of critical appraisal skills than those in the control group (mean score: intervention group, 58% +/- 8 vs control group, 50% +/- 8), with a large effect size of 1.06 standard deviation units (t+3.92, P <.0001). Training conditions accounted for 22% of the variance in total scores. CONCLUSIONS: A multifaceted, Internet-based intervention resulted in improved critical appraisal skills of practicing general surgeons.  相似文献   
104.
Many small synaptic inputs or one large input are needed to influence principal cell firing, whereas individual quanta exert little influence. However, the role of a quantum may be greater for small interneurons with high input resistances. Using dynamic clamp recordings, we found that individual quanta strongly influence rat cerebellar stellate cell firing. When the frequency of synaptic inputs was low, the timing of recent spikes regulated the influence of excitatory quanta. In contrast, when input frequency was high, spike timing was less important than interactions with other inputs. Inhibitory quanta rapidly terminated firing, whereas small numbers of coincident excitatory quanta reliably and rapidly triggered firing. Our results suggest that stellate cells achieve temporal precision through coincidence detection and disynaptic inhibition, despite their high resistances and long membrane time constants. Thus, we propose that small interneurons can process synaptic inputs in a fundamentally different way from principal cells.  相似文献   
105.
Concern for the recognition, support, and rights of victims within the criminal justice system has grown in recent years, leading to legislative and procedural changes in the administration of justice that have improved the experiences of victims. What is not clear is whether all victims have benefited from changes in the system regardless of race and social class. This study investigates the experiences Aboriginal people who are victims of sexual violence have with the Canadian criminal justice system. The authors seek to explore perspectives about their encounters with the judicial system from the point of first contact with the police through involvement with the court and community service providers, utilizing grounded theory qualitative methodology. They conclude that race is a key determinant in the manner in which a victim will be perceived by the people in the justice system and the manner in which the victim will approach the judicial process.  相似文献   
106.
Bradley  WG  Jr; Kortman  KE; Burgoyne  B 《Radiology》1986,159(3):611-616
The signal intensity of the cerebrospinal fluid (CSF) in the cerebral aqueduct and lateral ventricles on magnetic resonance (MR) images was evaluated in 16 healthy individuals and in 32 patients with various forms of hydrocephalus (20 with chronic normal pressure hydrocephalus [NPH], seven with acute communicating hydrocephalus, and five with hydrocephalus ex vacuo [atrophy]). The low signal intensity frequently observed in the cerebral aqueduct is believed to reflect the pulsatile motion of CSF, which is related to the cardiac cycle. While this "aqueductal flow void phenomenon" can be observed in healthy individuals, it is most pronounced in patients with chronic, communicating NPH; is less evident in patients with acute, communicating hydrocephalus; and is least evident in patients with atrophy. Ventricular compliance is known to be essentially normal in atrophy; mildly decreased in acute, communicating hydrocephalus; and severely decreased in NPH. The degree of aqueductal signal loss is believed to reflect the velocity of the pulsatile CSF motion, which in turn depends on the relative ventricular compliance and surface area.  相似文献   
107.
Fitness testing and career progression in AFL football   总被引:1,自引:0,他引:1  
Relationships between fitness testing and career progression in the Australian Football League (AFL) are under-explored. This study investigated relationships between anthropometric and fitness tests conducted at the annual AFL National Draft Camp and subsequent career progression of players. A total of 283 players was tested over three consecutive camps (1999-2001). The anthropometric and fitness measures were: height, mass, sum of skinfolds, 20-m sprint test, vertical jump (standing and bilateral running), agility run and a multi-stage incremental shuttle run. The five outcome variables were: drafted (yes/no), AFL debut (yes/no), number of AFL games played to the end of 2003, and subjective ratings of career potential and career value (5-point scale). Of 205 players (72%) subsequently drafted, 166 (59%) eventually made their AFL debut. Players drafted to AFL clubs were faster over 5 m, 10 m and 20 m, ran further in the shuttle run and ran marginally faster in the agility test than players not drafted. Multi-regression analysis showed small to moderate correlations (r = 0.27-0.31) between the designated outcome variables and selected fitness tests: 20-m sprint time (faster), agility run test (faster), and running vertical jump (higher absolute height and smaller difference between left and ride sides). Regression analysis for the standing vertical jump relative to standing reach height showed a counterintuitive negative correlation with positive outcomes, possibly reflecting non-compliance with testing procedures by the less successful athletes. We conclude that the 20-m sprint, jump, agility and shuttle run tests have a small but important association with career progression of AFL footballers.  相似文献   
108.
Champlin  RE; Ho  WG; Feig  SA; Winston  DJ; Lenarsky  C; Gale  RP 《Blood》1985,66(1):184-188
We analyzed the effect of antithymocyte globulin (ATG) with or without androgens in 121 patients with aplastic anemia. Fifty-three patients with moderate to severe aplastic anemia were prospectively randomized to receive ATG with or without oral androgens. Eleven of 26 patients (42%) receiving ATG plus androgen responded, including three complete and eight partial responses. Twelve of 27 patients (44%) receiving ATG plus placebo responded, including five complete and seven partial responses. The difference in response rates was not significant (P greater than .9). Survival was also comparable in the two groups; for patients with severe aplastic anemia, actuarial survival at two years was 55% +/- 24% (95% confidence interval) in patients receiving ATG plus androgen compared with 50% +/- 24% in the ATG plus placebo group (P = .65). Furthermore, results in both groups were indistinguishable from those obtained in 68 historical controls receiving ATG without androgens. These data indicate that androgens are not required in order to respond to antithymocyte globulin and the addition of androgens, as used in this trial, did not significantly improve response rates to ATG treatment.  相似文献   
109.
Objectives  The ability to innovate new solutions in response to daily workplace challenges is an important component of adaptive expertise. Exploring how to optimally develop this skill is therefore of paramount importance to education researchers. This is certainly no less true in health care, where optimal patient care is contingent on the continuous efforts of doctors and other health care workers to provide the best care to their patients through the development and incorporation of new knowledge. Medical education programmes must therefore foster the skills and attitudes necessary to engage future doctors in the systematic development of innovative problem solving. The aim of this paper is to describe the perceptions and experiences of medical students in their third and fourth years of training, and to explore their understanding of their development as adaptive experts.
Methods  A sample of 25 medical students participated in individual 45–60-minute semi-structured interviews. Interviews were audiotaped, transcribed and entered into NVivo qualitative data analysis software to facilitate a thematic analysis. The analysis was both inductive, in that themes were generated from the data, and deductive, in that our data were meaningful when interpreted in the context of theories of adaptive expertise.
Results  Participants expressed a general belief that, as learners in the health care system, exerting any effort to be innovative was beyond the scope of their responsibilities. Generally, students suggested that innovative practice was the prerogative of experts and an outcome of expert development centred on the acquisition of knowledge and experience.
Conclusions  Students' perceptions of themselves as having no responsibility to be innovative in their learning process have implications for their learning trajectories as adaptive experts.  相似文献   
110.
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