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41.
OBJECTIVE--To determine the rate, type, and severity of injuries to child hockey players as well as assessing coaches', parents', and players' attitudes and knowledge of hockey. DESIGN--A prospective observation of a population's injuries using injury-reporting forms and surveys. SETTING--A community-organized hockey program in Minnesota. PARTICIPANTS: One hundred fifty boys, aged 9 through 15 years, who played ice hockey during the 1990-1991 winter season. MEASUREMENTS AND MAIN RESULTS--Injuries were reported by multiple observers, including coaches, managers, and trained independent observers at the time an injury occurred; coaches, parents, and players were surveyed regarding hockey injuries, knowledge, and attitudes. One in three players experienced an injury during the season. The most common injuries were contusions. Six of 100 players experienced injuries severe enough to require cessation of physical activities for 8 to 25 days or longer. Weight differences of 53 kg and height differences of 55 cm were reported between Bantam-aged players (13 through 15 years), and body contact, including legal checks, accounted for 86% of injuries during games. Illegal checks and violations were associated with 66% of injuries during games, yet only four penalties (14%) were assessed. In addition, one in three games in which an injury resulted was described as hostile and 15% of the injuries were considered intentional. CONCLUSIONS--Eliminating violence and body checking for prepubertal boys while emphasizing rule enforcement and good sportsmanship are recommended.  相似文献   
42.
Abstract: The aim of this study was to determine changes in Sydney general practitioners' (GPs) knowledge about, attitude towards and intention to recommend screening mammography over the two years since a screening mammography program was first implemented in the Central Sydney Health Service (CSHS) area. 123 GPs from the CSHS area were selected from a list maintained by the Breast X-ray Programme, while 127 GPs from the rest of Sydney were selected from the Yellow Pages telephone directory. The overall response rate was 84 per cent. Outcomes were assessed by a self-administered questionnaire covering knowledge, attitudes and beliefs, self-report of recent referral practice, intention to recommend, and sources of information about mammography screening. Demographic data were also collected. Results showed that overall knowledge has increased both inside and outside the CSHS area, but important deficiencies in knowledge remain in both areas. Attitudes to screening mammography have improved in the CSHS area, especially regarding the efficacy of screening mammography and patient compliance. Importantly, positive views of screening mammography have declined outside the CSHS area, especially about whether screening mammography can save women's lives. GPs in both areas remain concerned about costs. The presence and strategies of the Breast X-ray Programme have had some positive effect on the attitudes of GPs towards, but not knowledge of, screening mammography.  相似文献   
43.
The use of laparoscopic surgical techniques is now being applied to a variety of operations traditionally performed in an open fashion. Twenty patients underwent laparoscopic-guided large and small bowel surgery at our institution from March 1991 to April 1992. The indications for surgery included polyps, obstruction, bleeding, and perforation, and pathologic diagnoses included benign polyps, lipomas, inflammatory bowel disease, perforation of a jejunal diverticulum, colonic arteriovenous malformations, and adenocarcinoma. Mobilization of the colon, ligation of the mesentery, and closure of the mesenteric defect were performed using the laparoscopic equipment. One trocar site was enlarged to 3 cm to deliver the bowel through the abdominal wall. All anastomoses were hand-sewn. Postoperative hospitalization ranged from 2 to 31 days (median, five days). No mortality was noted, and morbidity was 20 percent. We conclude that laparoscopic-guided bowel surgery is technically feasible and should translate into shorter hospitalization and less patient discomfort.  相似文献   
44.
Intravenous self-administration of GBR 12909, an indirect dopamine agonist, was examined on a Fixed Ratio (FR 1) and a Progressive Ratio (PR) schedule of reinforcement in rats. Subjects were first trained to self-administer cocaine (1.5 mg/kg/inj) during daily 5 h sessions, after which GBR 12909 (0.187–1.5 mg/kg/inj) was substituted. On the FR 1 schedule, the inter-infusion interval for GBR 12909 self-administration was directly related to dose and was approximately three times longer than that established for equivalent doses of cocaine. Breaking points on the PR schedule were comparable for GBR 12909 and cocaine self-administration. The data indicate that, compared to cocaine, GBR 12909 has a longer duration of action and a similar reinforcing efficacy.  相似文献   
45.
The portrayal of alcohol was examined in a systematic sampleof 50 programmes broadcast on British television. Four out offive programmes contained visual or verbal references to alcohol.On average, there was a reference to alcohol in every 6 minutesof programming. The programmes showed more alcohol being consumedthan soft drinks or beverages, but there were few referencesto the hazards of alcohol consumption. The main recommendationis that television companies should accept a responsibilityfor presenting a more realistic and healthier approach to theuse of alcohol in Britain  相似文献   
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The purpose of this research was to investigate differential manifestation of depressive symptomatology among adolescents from diverse ethnocultural groups. Data from a national survey of persons 12 to 17 years of age (N = 2200) were analyzed, comparing responses of Anglo, African, Mexican, and other Hispanic Americans with a 12-item version of the Center for Epidemiologic Studies Depression Scale. The results indicated minimal differences in terms of item response and internal consistency-reliability among the four adolescent groups. However, there were differences in patterns of item endorsement, as indicated by principal component factor analysis. Anglo- and African Americans exhibited similar factor structure, represented by negative affect, positive affect, and psychosomatic symptoms. The two Hispanic groups also exhibited a three-dimensional pattern, but there was a tendency among Hispanic adolescents for somatic symptoms and negative affect symptoms to cluster together. This pattern may indicate a more prominent role of somatic complaints in the presentation of depression among Mexican Americans and other Hispanics.  相似文献   
49.
A modified labioplasty to improve the cosmetic appearance after feminizing genitoplasty is described. Good results were obtained in all five patients in whom the technique was utilized.  相似文献   
50.
Five studies were conducted to measure changes in the perception and production of selected speech targets, with training, in three prelingually deaf patients. The two adults and one adolescent were implanted with the Cochlear (Nucleus) multiple-electrode prosthesis. The studies were perception and production of nasal consonants; perception of syllable-final consonants; perception and production of alveolar consonants; auditory-visual perception of alveolar consonants; and perception and production of vowels. Perceptual data were collected in the audition (implant)-alone condition, except for the auditory-visual perception of alveolar consonants where the audition-alone, vision-alone, and auditory-visual conditions were used. Speech perception data in the audition-alone condition were also collected from four postlingually deaf adult implant patients, without training, to indicate differences between the two classes of patients. The three prelingually deaf patients generally showed some improvements in speech production. In perception, improvements were recorded only for individual patients in some studies. The performance of the adolescent was better than that of the two adults in all cases. The perceptual performance of the postlingually deaf patients was superior to that of the prelingually deaf patients in all cases.  相似文献   
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