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The acromioclavicular joint is a potential source of pain in the shoulder. There are a variety of disorders that can affect this joint, including distal clavicle osteolysis, posttraumatic arthritis, osteoarthritis, and rheumatoid arthritis. Nonoperative treatment for this condition with nonsteroidal medication and activity modification can alleviate the pain. When conservative treatment is exhausted, surgical resection of the distal clavicle is often necessary. Arthroscopic resection of the distal clavicle preserves the acromioclavicular ligaments to prevent postoperative distal clavicle instability. The procedure is performed in either the beach chair or lateral position and requires the use of a shaver, electrocautery, and a burr for soft tissue and debridement and bone resection.  相似文献   
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STUDY OBJECTIVES: Accurate core temperature measurement in severely hypovolemic patients can be difficult to achieve. We used a dog model to determine both a convenient method of measuring core temperature and the relative accuracy of the multiple sites. DESIGN: Prospective laboratory (animal model) study. SETTING: Operating suites in the Animal Care Department. PARTICIPANTS: Eight adult, anesthetized greyhound dogs. INTERVENTIONS: Continuous temperature monitoring by thermistors placed in the brain, central vein, tympanic membrane, bladder, rectum, esophagus, and subcutaneous tissue. Hemorrhage to 65% initial intravascular volume and autologous transfusion of cooled blood, during which serial temperature measurements were recorded. MEASUREMENTS AND MAIN RESULTS: The readings were analyzed with Pearson's correlation coefficient. Brain temperature correlated very well with tympanic membrane temperature throughout the course (r = .869, P less than .0005). Rectum, bladder, and esophagus also correlated well with brain. Central venous temperature, however, correlated poorly with temperatures at all other sites, reflecting the marked swings in intravascular temperature caused by cold transfusion. These wide variations were damped at the other sites. The best correlation of central venous temperature was with brain and bladder, although tympanic membrane correlation was fair. CONCLUSIONS: Because intravascular hypothermia appears to be the source of the arrhythmias and hemostatic abnormalities often seen during the early resuscitation of hypovolemic patients, our results suggest bladder or tympanic membrane as the initial temperature site. After the initial resuscitation, end organ (eg, brain) temperature is the most important and is most accurately reflected by tympanic membrane temperature.  相似文献   
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The objective of this demonstration project was to determine if school-based harm minimization drug education was potentially acceptable and effective for junior and senior high school students in Nova Scotia. We conducted a four-year quasi-experimental intervention using mixed quantitative and qualitative methodologies. The intervention was a co-operative participatory research project with various activities determined by the participants. The project involved a partnership of four schools, two school boards, two regional addiction services, the provincial department of health, and a university. The outcomes evaluation was based on a sample of 1117 and 849 students in the intervention schools, compared with 3755 and 4247 students in the rest of the province, in 1998 and 2002, respectively. The evaluation of acceptability was based on an analysis of 491 documents generated from 1998 to 2002. The outcomes of effectiveness were specific risks and harmful consequences associated with substance use. We found that harm minimization was an acceptable approach to drug education targeting the senior high school population, and there was also some evidence of effectiveness in that age group in that the prevalence of several risks and negative consequences of substance use decreased significantly in the intervention schools relative to the rest of the province. In junior high school, harm minimization was found to not be an acceptable approach to drug education. This demonstration project provides evidence that school-based harm minimization may be acceptable and effective in senior high schools but may not be acceptable in junior high schools.  相似文献   
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The employment state of men living in the homes of children at the time that child abuse was diagnosed was determined. The series included a wide range of abuse, including non-accidental injury, failure to thrive, neglect, and emotional deprivation. Two cohorts of children seen during 1974-9 and 1980-5 were compared; these periods were chosen because a large increase in unemployment began in Sheffield in 1980. Although the proportion of the men without work was significantly increased during the second period, this increase could not be ascribed to the rise in either long term or short term unemployment among those who had previously been in regular employment. It was accounted for by a rise in the proportions of single parent families and families in which the resident man had never had regular employment. This may reflect an increase in pregnancies among young mothers. There was no evidence to support the belief that the loss of a job in otherwise stable families leads to an increase in child abuse.  相似文献   
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Natural history of the benign breast lump   总被引:2,自引:0,他引:2  
A prospective study of 112 patients with clinically discrete benign breast lumps has shown that 68 per cent of patients experienced resolution of their lumps over a period of up to 2 years. Resolution of both fibro-adenomas and discrete areas of fibro-adenosis was observed. Diagnosis was achieved by clinical examination and fine needle aspiration cytology. Four patients thought clinically to have benign disease were proven by cytology to have a carcinoma, but no patient with a cytopathological diagnosis of benign disease has developed cancer during or subsequent to this study. We recommend that patients under 35 years of age with clinically and cytologically benign breast lumps can be offered the option of non-excision in the reasonable expectation of resolution of their lesion.  相似文献   
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Fifty-six patients with Barrett's oesophagus diagnosed between 1977 and 1986 were prospectively studied by 6-monthly endoscopic surveillance and biopsy. During follow-up to-date, four patients have developed high-grade dysplasia and three have adenocarcinoma of the oesophagus. Two of the adenocarcinomas were preceded by progressively severe dysplastic changes but in the third no dysplasia had been previously detected. The incidence of adenocarcinoma was 1 per 56 patient-years of follow-up. Changes in symptomatology or gross endoscopic appearances were usually absent, even after adenocarcinoma had developed, indicating that biopsy is essential for early diagnosis. The high risk of malignant change makes endoscopic surveillance advisable in all patients with Barrett's oesophagus.  相似文献   
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This population-based study documented beta-blocker use in 59/569 cases with incident fracture and 112/775 controls. OR for fracture associated with beta-blocker use was 0.68 (95%CI, 0.49-0.96). Beta-blockers were associated with higher BMD at the total hip (2.5%) and UD forearm (3.6%) after adjusting for age, anthropometry, and thiazide use. Beta-blocker use is associated with reduced fracture risk and higher BMD. INTRODUCTION: Animal data suggests that bone formation is under beta-adrenergic control and that beta-blockers stimulate bone formation and/or inhibit bone resorption. MATERIALS AND METHODS: We evaluated the association between beta-blocker use, bone mineral density (BMD), and fracture risk in a population-based study in Geelong, a southeastern Australian city with a single teaching hospital and two radiological centers providing complete fracture ascertainment for the region. Beta-blocker use was documented for 569 women with radiologically confirmed incident fractures and 775 controls without incident fracture. Medication use and lifestyle factors were documented by questionnaire. RESULTS: Odds ratio for fracture associated with beta-blocker use was 0.68 (95% CI, 0.49-0.96) for any fracture. Adjusting for age, weight, medications, and lifestyle factors had little effect on the odds ratio. Beta-blocker use was associated with a higher BMD at the total hip (2.5%, p = 0.03) and ultradistal forearm (3.6%, p = 0.04) after adjustment for age, anthropometry, and thiazide use. CONCLUSION: Beta-blockers are associated with a reduction in fracture risk and higher BMD.  相似文献   
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