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91.
The use of a valgus brace can effectively relieve the symptoms of unicompartmental osteoarthritis of the knee. This study provides an objective measurement of function by analysis of gait symmetry. This was measured in 30 patients on four separate occasions: immediately before and after initial fitting and then again at three months with the brace on and off. All patients reported immediate symptomatic improvement with less pain on walking. After fitting the brace, symmetry indices of stance and the swing phase of gait showed a consistent and immediate improvement at 0 and 3 months, respectively, of 3.92% (p = 0.030) and 3.40% (p = 0.025) in the stance phase and 11.78% (p = 0.020) and 9.58% (p = 0.005) in the swing phase. This was confirmed by a significant improvement at three months in the mean Hospital for Special Surgery (HSS) knee score from 69.9 to 82.0 (p < 0.001). Thus, wearing a valgus brace gives a significant and immediate improvement in the function of patients with unicompartmental osteoarthritis of the knee, as measured by analysis of gait symmetry.  相似文献   
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BACKGROUND/AIMS: Many tumor markers have been utilized in the follow-up care of colorectal cancer patients. No marker, however, has proven reliably accurate in detecting recurrent disease. METHODS: The strengths and weaknesses of currently available tumor markers are reviewed, with attention to related cost and efficacy. RESULTS: Tumor antigens, enzymes, and genetic markers have been used as tumor markers. CEA and CA 19.9 are the most widely utilized; however, genetic markers are the most promising for the future. CONCLUSIONS: Currently available markers have significant limitations. Development of genetic markers may greatly enhance our ability to predict prognosis and the need for adjuvant therapy. Marker-guided therapy may play an increasing role in this disease.  相似文献   
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Occupational exposures were investigated in a multicenter case-control study of clinically and histologically diagnosed idiopathic pulmonary fibrosis (IPF), a chronic diffuse interstitial lung disease of unknown etiology. Results are based on 248 cases, aged 20-75 years, diagnosed at 16 referral centers between January 1989 and July 1993. There were 491 controls ascertained by random digit dialing and matched to cases on sex, age, and geographic region. Data were collected using a standard telephone questionnaire. Occupational factors were based on a detailed history of jobs lasting 6 months or more and job activity, hobby, and specific substance checklists. Several occupational factors, adjusted for age and smoking in conditional multivariate logistic regression analyses, were significantly associated with IPF: farming (odds ratio (OR) = 1.6, 95% confidence interval (CI): 1.0, 2.5); livestock (OR = 2.7, 95% CI: 1.3, 5.5); hairdressing (OR = 4.4, 95% CI: 1.2, 16.3); metal dust (OR = 2.0, 95% CI: 1.0, 4.0); raising birds (OR = 4.7, 95% CI: 1.6, 14.1); stone cutting/polishing (OR = 3.9, 95% CI: 1.2, 12.7); and vegetable dust/animal dust (OR = 4.7, 95% CI: 2.1, 10.4). Interaction was detected between smoking and exposure to livestock (p = 0.06) and farming (p = 0.08). Results confirm previous studies showing increased risk associated with dusty environments.  相似文献   
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Analysis of pulmonary fat embolism in blunt force fatalities   总被引:14,自引:0,他引:14  
OBJECTIVE: To investigate the incidence, severity, and origin of pulmonary fat embolism (PFE) in persons dying from blunt force trauma within 24 hours of injury. METHODS: The study population consisted of blunt force fatalities. Controls were subjects dying from natural causes or nonblunt force injury. Tissue was removed from lung lobes and prepared for histologic examination using osmium tetroxide to stain for fat. Lung sections were graded for PFE on a scale of 0 (no emboli) to 4 (five or more emboli in a majority of fields). RESULTS: The blunt force group consisted of 56 decedents. Mortality was 93% within 4 hours. Fractures were present in 54 (96%) of decedents, and soft tissue injury was universal. Thirty eight (68%) of decedents were positive for PFE vs. 3 of 20 (15%) in controls. Mean score for PFE was 2.94 +/- 1.15 and 1.01 +/- 0.94, respectively (p < 0.005). Bone marrow emboli were not observed in any of the sections. Severity of PFE was positively associated with survival time. Analysis of PFE against sex, age, height, weight, number of injuries, and number of fractures showed no significant correlations. CONCLUSIONS: A significant degree of PFE develops rapidly in a majority of persons dying of blunt force trauma. Although the source of fat for embolization has been suggested to be bone marrow, no evidence of myeloid tissue was found in any of the lung sections. Nor was there a correlation of PFE and number of fractures. Soft tissue injury is considered the primary cause of PFE.  相似文献   
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BACKGROUND: Patients with ulcerative colitis (UC) have an increased risk of developing colorectal cancer. The current screening protocol involves an annual colonoscopy and biopsy after the patient has had the disease for 8 years. This, however, does not prevent the development of colorectal cancer. HYPOTHESIS: A microsatellite marker for IBD1 may identify individuals who are at greater risk of developing dysplasia and therefore colorectal cancer. DESIGN: Case-control study. SETTING: Single surgical practice. PATIENTS AND METHODS: DNA was extracted from peripheral leukocytes of 152 patients: 22 with UC and dysplasia; 48 with UC and no dysplasia; 24 with colorectal cancer; and 58 with noninflammatory bowel disease, nonmalignant gastrointestinal tract disease who were used as control patients. A microsatellite marker for IBD1 (D16S541) was amplified by polymerase chain reaction. Genotypes were identified using autoradiography. RESULTS: Six alleles and 15 genotypes were identified for marker D 16S541. Genotype CC was found in 33% (8/24) of cancer patients but only 12% (7/58) of controls (chi2 = 5.5; P = .02). Thirty-two percent (7/22) of patients with dysplastic UC also had this genotype, whereas only 8% (4/ 48) of patients with nondysplastic UC had the genotype (chi2 = 4.6; P = .03; vs controls: chi2 = 3.1; P = .08). CONCLUSIONS: This microsatellite marker for IBD1, when combined with other markers, has the potential to be used as a screening tool for colorectal cancer and dysplasia in patients with UC. Such a marker would be of particular use in improving the sensitivity and specificity of the current screening protocol for dysplasia and colorectal cancer for patients with UC.  相似文献   
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