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81.
82.
Cold application is commonly used before strenuous exercise due to its hypalgesic effects. Some have questioned this procedure because of reports that cold may reduce isokinetic torque. However, there have been no investigations of actual physical performance following cold application. The purpose of this study was to determine if a 20-minute ice immersion treatment to the foot and ankle affected the performance of three agility tests: the carioca maneuver, the cocontraction test, and the shuttle run. Twenty-four male athletic subjects were tested during two different treatment sessions following an orientation session. Subjects were tested following a 20-minute 1°C ice immersion treatment to the dominant foot and ankle and 20 minutes of rest. Following each treatment, subjects performed three trials of each agility test, with 30 seconds rest between each trial, and 1 minute between each different agility test. The order in which each subject performed the agility tests was determined by a balanced Latin square. A MANOVA with repeated measures was used to determine if there was an overall significant difference in the agility times recorded between the cold and control treatments and if the order of the treatment sessions affected the scores. Although the mean agility time scores were slightly slower following the cold treatment, cooling the foot and ankle caused no difference in agility times. Also, there was no difference resulting from the treatment orders. We felt that the slightly slower scores may have been a result of tissue stiffness and/or subject's apprehension immediately following the cold treatment. Cold application to the foot and ankle can be used before strenuous exercise without altering agility. 相似文献
83.
84.
In 1989, Trent Regional Health Authority set up a Commission to enquire into the organization of day case surgery and encourage its use. Improved methods for measuring and comparing day surgical activity were developed using routine data sources. These revealed even greater variation between hospitals and specialties in the amount of day surgery performed than did the usual analyses. Arrangements for day surgery differed considerably between specialties. Few theatres, beds, or surgeons' sessions were dedicated to day surgery, but general surgery and gynaecology used dedicated facilities more than other specialties such as ENT and ophthalmology. The Commission visited each hospital and found that day case facilities, organization and resources were poor in many of them. It was able to make specific recommendations for improvements. Day case surgery increased substantially over the period that the Commission operated, most hospitals reported that it had influenced changes in day surgery and that it had been useful, especially for local managers. Schemes to increase day surgery were funded. Highlights two elements for managing change: the need for good information about a problem, and the need to extend ownership of the issue throughout the organization. 相似文献
85.
Thomas BV Knight AW Maier KJ 《Archives of environmental contamination and toxicology》1999,36(3):295-300
The input of selenium from subsurface agricultural drainage into surface water systems can result in the accumulation of
toxic concentrations of selenium in aquatic food chains. Elevated selenium concentrations in aquatic systems is a significant
environmental problem in many areas of the United States. A laboratory investigation was conducted to determine the dominant
route of selenium bioaccumulation by the corixid Trichocorixa reticulata, an important food chain organism. The roles of waterborne and foodborne exposure in selenium bioaccumulation were examined
using 48-h bioassays. Waterborne selenium concentrations ranged from 0 to 1,000 μg Se/L as selenate. A mixture of two species
of blue-green algae cultured in media with selenium concentrations ranging from 0 to 1,000 μg Se/L as selenate was used as
a corixid diet in the foodborne treatments. Corixids exposed to waterborne selenate did not accumulate selenium above control
concentrations. Corixids fed algae exposed to ≥100 μg Se/L as selenate had significantly higher selenium concentrations than
control organisms. These data suggest that corixids may be effectively isolated from the water and selenium accumulation is
solely through dietary exposure.
Received: 8 July 1998/Accepted: 21 October 1998 相似文献
86.
Junkins EP Knight S Lightfoot AC Cazier CF Dean JM Corneli HM 《The Journal of school health》1999,69(10):409-412
87.
Previous research has suggested that a relationship exists between craniofacial morphology and tooth wear. The primary objective of this study was to determine whether an individual's craniofacial morphology during childhood is related to the degree of tooth wear that occurs in that same individual's adult dentition. Pretreatment orthodontic records taken during the mixed dentition (T1) and follow-up records taken an average of 20 years later (T2) were available for 165 orthodontic patients. Incisal/occlusal tooth wear was measured on a tooth-by-tooth basis from T1 and T2 casts using a four-category scoring system. Measures of craniofacial morphology were made from the T1 lateral cephalometric radiograph. Multiple regression analysis indicated that adult wear was associated with the T1 cephalometric measures of ANB (p = 0.017) and the interaction between ramal height and sex (p = 0.039). These results suggest that the craniofacial morphology observed during childhood has a small but significant relationship to adult tooth wear. 相似文献
88.
BACKGROUND: Acute rejection (AR) is an important risk factor for long-term renal graft loss. Furthermore, donor age is also associated with graft outcome. We analyzed the combined effects of cadaver donor age and AR on long-term graft survival. METHODS: A retrospective review was made of 112 cadaver renal transplants at a single center. Only grafts functioning at least 3 months were included in this analysis. RESULTS: The 3-year survival of AR-free grafts was superior to that of grafts with AR (98% vs 67%, P < .001). Within the AR cohort donor age > 50 years (P < .05) had an additional negative impact on graft survival. The 3-year survival of an older donor graft with AR was 33% versus 82% for a younger donor graft with AR. CONCLUSIONS: AR was a significant predictor of long-term graft loss. Older donor kidneys with AR had poorer graft survival than did younger donor kidneys with AR. 相似文献
89.
90.
STUDY DESIGN: An outcomes assessment of 14 elite college athletes who had undergone lumbar disc surgery was performed using the SF-36, a validated questionnaire that assesses quality of life. OBJECTIVES: To determine the outcomes and results of lumbar disc surgery in an elite group of athletes and compare the results with those in the general population and in age-matched control subjects. SUMMARY OF BACKGROUND DATA: Lumbar disc surgery is reported to be a highly successful procedure with excellent results. The outcome in elite athletes has not been assessed and compared with population norms and age-matched control subjects. METHODS: Fourteen athletes from schools in the National Collegiate Athletic Association with a mean age of 20.7, underwent lumbar discectomy for radiculopathy refractory to conservative treatment. Ten had a single-level microdiscectomy, three a two-level microdiscectomy, and one a percutaneous discectomy. Patients were evaluated at a mean follow-up of 3.1 years, underwent a detailed clinical evaluation, and filled out the SF-36 questionnaire. RESULTS: All 14 patients had improvement of pain with elimination of the radicular component, took less medication than before surgery, and returned to recreational sports. Nine patients, all with a single level microdiscectomy, returned to varsity sports. Five athletes prematurely retired from competitive sports because of continued symptoms. Three of the athletes who retired underwent two-level procedures, and one had a percutaneous discectomy. SF-36 scores for bodily pain, physical role, and social and mental health roles were significantly lower in those athletes who retired. Patient scores were also compared with those in a group of noninjured age-and sport-matched college athletes. There were no differences between injured and noninjured athletes, but both groups had scores significantly lower than normal values in an age-matched group for bodily pain, physical role, general health, and social function. CONCLUSIONS: All patients were satisfied with their surgeries, were greatly improved, and were pain free in activities of daily living. For a single-level microdiscectomy, the success rate in elite athletes is excellent, with 90% of athletes able to return to a high level of competition. Two-level disease may be associated with a less favorable outcome. 相似文献