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51.
OBJECTIVES: To determine whether the increase in the incidence of injury found for the first summer season in which rugby league (RL) was played in the UK was repeated in subsequent summer seasons. DESIGN: A retrospective and prospective cohort study design. SETTING AND PARTICIPANTS: Injuries were recorded from all players who took part in 141 games over 3 summer seasons (1997 to 1999) for 1 professional team. These were compared against rates from previously collected data for 3 earlier winter and 1 summer season. ASSESSMENT OF RISK FACTORS: For each injury it was recorded in which season it occurred; how many games or training sessions, if any, were subsequently missed; the type, site and severity of injury. MAIN OUTCOME MEASURES: Injuries were reported as rate per 1000 hours, also broken down into severity according to the number of games missed and whether subsequent training sessions were missed. RESULTS: A sustained increase in injury incidence has been found comparing summer RL over RL played in the winter. There was an increase in injury rates for all sites and types, but not all reached significance. CONCLUSIONS: Data collected over 6 seasons indicate a higher risk of sustaining an injury playing summer RL, but the cause may be related to a combination of factors. These may include the ground or weather conditions associated with summer rugby, player characteristics or changes in the game itself and future research needs to investigate these further.  相似文献   
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Studies on the effectiveness of pain management have uniformly concluded that health care providers underestimate or undertreat pain. In the emergency department (ED) in which this study was conducted, physicians receive formal didactic and bedside teaching on pain recognition and management in order to heighten the awareness of patient's need for pain control. The purpose of this study was to determine if this outpatient pain management of patients with acute, painful conditions is better than that reported in the medical literature. In this prospective study, 110 adult patients who had an acute, painful diagnosis were telephoned 48 hours after discharge from the ED and asked if they felt their pain at home was well controlled. Patient satisfaction with pain control was higher (91%) than that reported in the medical literature. Also, pain medication was provided more frequently by this study's ED (95%). Education on pain awareness and treatment is a way to improve pain management.  相似文献   
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Congenital cardiac malformations in Adams-Oliver syndrome   总被引:1,自引:0,他引:1  
Whole genomic hprt clones were used in Southern analysis to screen the integrity of the hprt gene in a family that includes a patient with HPRT enzyme deficiency causal to Lesch-Nyhan syndrome. A 5 kb DNA sequence deletion was found to have its endpoints in the first and third introns. The probes identified the carrier status of female family members, aided by an RFLP carried by the mother's normal X-chromosome.  相似文献   
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1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator.  相似文献   
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Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD.  相似文献   
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BACKGROUND: Mixed venous saturation (S & OV0456;o2) is an important measurement that helps guide the care of critically ill patients. Invasive S & OV0456;o2 assessment in infants and children is often avoided because of the inherent risks. A noninvasive tissue saturation (S to 2) monitor has recently been developed that uses near-infrared spectroscopy to measure oxyhemoglobin saturation in muscle. In adult and animal studies, S to 2 correlated with oxygen delivery and S & OV0456;o2. There has been no evaluation in pediatric patients. OBJECTIVE: To evaluate tissue saturation as a noninvasive measure of mixed venous saturation in children. DESIGN: A prospective observational study. SETTING: Catheterization laboratory in a tertiary care children's medical center. PATIENTS: We studied 98 children (49 without intracardiac mixing and 49 with intracardiac mixing) 相似文献   
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Chronic polypoid rhinosinusitis (CRS) is a common disease, affecting approximately 16% of the adult population in the US every year. In addition to many well known predisposing factors, an association with reflux disease is hypothesized. Such an association might explain the recurrence of polyposis in the face of improved surgical techniques and postsurgical treatment of CRS. At present it is unclear whether extraesophageal reflux directly injures the sinus mucosa, whether gastroesophageal reflux leads to vagus-mediated neuroinflammatory changes, or whether both mechanisms occur separately or simultaneously. In patients suffering from recurrent CRS (n=20) and healthy volunteers (n=20), ambulatory 24 h two channel pH testing was performed. The number of reflux events, the fraction of the total time during which pH was below 4, and the reflux area index (RAI) were determined in the esophagus as well as in the hypopharynx. Patients with recurrent CRS had significantly more reflux events in the esophagus and the fraction of pH<4 and the RAI were increased up to 10-fold compared to healthy volunteers. In contrast to the esophagus, these differences were not observed in the hypopharynx. Recurrent CRS is often associated with GERD but not with EER. Recurrent disease or prolonged recovery after surgery should raise the suspicion of reflux disease as a possible triggering factor. Because GERD itself cannot be diagnosed by laryngoscopy, and because of the subjectivity of symptoms such as heartburn, the otolaryngologist should consider double-probe pH testing as the diagnostic procedure of choice.  相似文献   
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