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91.
Lasser  EC; Lang  JH; Lyon  SG; Hamblin  AE; Howard  MM 《Radiology》1981,140(1):11-15
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%.  相似文献   
92.
Patient dosage in computed tomography   总被引:1,自引:0,他引:1  
McCullough  EC; Payne  JT 《Radiology》1978,129(2):457
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93.
Multirater agreement of arthroscopic grading of knee articular cartilage   总被引:2,自引:0,他引:2  
BACKGROUND: Acute and chronic cartilage injury of the knee has an important impact on prognosis. The validity of the classification of such injuries is critical for prospective multicenter studies. The agreement among multiple surgeons at different institutions for articular cartilage lesions has not been established. HYPOTHESIS: Arthroscopic classification of articular cartilage lesions is reliable and reproducible and can be used for multicenter studies involving multiple surgeons. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 1. METHODS: A total of 6 surgeons from 5 centers reviewed 31 videos of articular cartilage lesions. With grade 2 and grade 3 combined for the analysis, observed agreement ranged from 81% to 94%, and kappa ranged from 0.34 to 0.87. An additional 22 videos comprising grade 2 and grade 3 lesions were analyzed, and the observed agreement was 80%, with an overall kappa of 0.47. CONCLUSION: Arthroscopic grading of articular cartilage lesions is reproducible among surgeons at different centers. CLINICAL RELEVANCE: Articular cartilage lesions can be reliably classified among surgeons at different sites. Such reliability is important for multicenter clinical research studies involving arthroscopic knee surgery.  相似文献   
94.
OBJECTIVE: The aim of the present study is to investigate the effects of psychological factors on plasma lipid levels among rural women of central Wisconsin and to compare the effects of these variables among normal-weight and overweight women. METHODS: Stratified sampling was used to select a random sample (n=1500) of farm and non-farm women aged 25 to 71 years from the Central Marshfield Epidemiologic Study Area. The baseline examination included measurements of blood pressure, skin folds, height, weight, and fasting blood lipids, glucose, and insulin. Framingham study questionnaires were employed to measure anger, anxiety, tension, and marital disagreement. The Spielberger Trait anger-reaction subscale was employed to assess proneness to anger. RESULTS: Among normal-weight women, a positive association was found between anger-reaction scores and cholesterol (b=0.008), ratio (b=0.014), triglycerides (b=0.02), and LDL (b=0.07). The odds of elevated cholesterol were highest among women with high scores on the Speilberger anger-reaction scale (OR=2.0) and anger discussion scale (OR=2.0), while the odds were less among women with high scores on the anger-out scale (OR=0.59). However, among overweight women, we found only scores on the Framingham anger-discussion scale as an important factor to determine the plasma lipid levels. CONCLUSION: Anger management may help to sever the link between psychological factors and CHD risk factors. Intervention intended to prevent cardiac events through the reduction of stress and modification of related psychological risk factors have successfully improved the CHD risk factors profile. Similar studies are needed to determine the efficacy of intervention for the primary prevention of CHD risk factors.  相似文献   
95.
BACKGROUND: The purpose of the current study was to evaluate whether a totally implanted valved subcutaneous port system would have fewer complications as compared to a standard nonvalved port. METHODS: Study subjects requiring port placement were randomized to receive a valved port (PASV; Boston Scientific, Natick, MA) or a nonvalved port (BardPort; Bard Accesss Systems, Salt Lake City, UT). Each port was placed with standard operative technique. Difficulty with blood return, excess time spent accessing the port, and required interventions were reported over the initial 180 days of port usage. RESULTS: Seventy-three patients were randomized to receive either a valved port (n = 37) or a nonvalved port (n = 36). No major complications were identified from port placement, and there were no differences in rates of infection between the 2 ports. A reported inability to withdraw blood was noted in the valved port group on 21 of 364 (5.8%) port accessions and in the nonvalved port group on 37 of 341 (11%) accessions (P = 0.02). Significantly more total time was spent ensuring adequate blood draw from nonvalved ports as opposed to valved ports (750 minutes vs. 1545 minutes, respectively) (P <0.03). CONCLUSIONS: This study revealed that the PASV valved port is associated with significantly fewer instances of poor blood return and less nursing access time, indicating that a port with a PASV valve may be superior to a nonvalved device.  相似文献   
96.
BACKGROUND: Establishing the validity of classification schemes is a crucial preparatory step that should precede multicenter studies. There are no studies investigating the reproducibility of arthroscopic classification of meniscal pathology among multiple surgeons at different institutions. HYPOTHESIS: Arthroscopic classification of meniscal pathology is reliable and reproducible and suitable for multicenter studies that involve multiple surgeons. STUDY DESIGN: Multirater agreement study. METHODS: Seven surgeons reviewed a video of 18 meniscal tears and completed a meniscal classification questionnaire. Multirater agreement was calculated based on the proportion of agreement, the kappa coefficient, and the intraclass correlation coefficient. RESULTS: There was a 46% agreement on the central/peripheral location of tears (kappa = 0.30), an 80% agreement on the depth of tears (kappa = 0.46), a 72% agreement on the presence of a degenerative component (kappa = 0.44), a 71% agreement on whether lateral tears were central to the popliteal hiatus (kappa = 0.42), a 73% agreement on the type of tear (kappa = 0.63), an 87% agreement on the location of the tear (kappa = 0.61), and an 84% agreement on the treatment of tears (kappa = 0.66). There was considerable agreement among surgeons on length, with an intraclass correlation coefficient of 0.78, 95% confidence interval of 0.57 to 0.92, and P < .001. CONCLUSIONS: Arthroscopic grading of meniscal pathology is reliable and reproducible. CLINICAL RELEVANCE: Surgeons can reliably classify meniscal pathology and agree on treatment, which is important for multicenter trials.  相似文献   
97.
OBJECTIVE: The aim of this work was to study the frequency of examining for diabetic eye and foot complications in an Australian population and to study factors associated with regular screening. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity, and Lifestyle Study (AusDiab) was a population-based study of 11,247 people from randomly selected areas of Australia. Participants identified as having previously diagnosed diabetes (n=475) were invited to participate in the complications study. Measures included foot examination, retinopathy photography, and self-report use of health care services. RESULTS: Seventy-seven percent of participants reported having an eye examination within the previous 2 years, and 50% reported having their feet examined by a health professional in the previous year. Type of diabetes treatment (odds ratio 1.46, 95% CI 0.85-2.50 for tablets versus diet alone and 4.17, 1.71-10.17 for insulin or insulin and tablets versus diet alone) and visiting a diabetes nurse educator in the previous 12 months (2.14, 1.18-3.87) were independent predictors of having had an eye examination. Duration of diabetes (1.33, 1.06-1.67 per year) and visiting a diabetes nurse educator in the previous 12 months (1.89, 1.20-2.95) were independent predictors of a foot examination. CONCLUSIONS: This study has shown that retinopathy screening is performed more frequently than foot screening in Australia. This may be due to the implementation of eye screening programs and awareness campaigns. Foot screening appears to be poor, with less than one-half of the population reporting a regular examination for foot complications. In Australia, diabetes nurse educators play a key role in promoting screening for diabetes complications.  相似文献   
98.
99.
Recent in vitro studies have suggested a potential role for antimony as a confounder in human health studies related to arsenic in drinking water. We measured tube-well water concentrations of antimony and arsenic in the Pabna region of Bangladesh, where arsenic concentrations are known to be elevated and the concentrations of antimony have not yet been thoroughly documented. Two hundred forty-five tube-well water samples were collected from various regions in Pabna, Bangladesh, as part of an ongoing case-control study. Water samples were analyzed for arsenic and antimony concentrations by inductively coupled plasma-mass spectrometry using U.S. Environmental Protection Agency method 200.8. The arsenic concentrations in the tube-well water samples ranged from < 1 microg/L to 747 microg/L. All 245 water samples had antimony concentrations < 1 microg/L. Based on consideration of the concentrations used the in vitro studies compared with field-observed concentrations, our results do not support the hypothesis that antimony would be a significant confounder in observed relationships between arsenic exposure through drinking water and potential health outcomes in Pabna, Bangladesh.  相似文献   
100.
OBJECTIVE: Although alcohol has been associated with death from a variety of causes, there are no recent data on the number of deaths in the United States attributable to harmful alcohol use. This study provides updated information on the number of deaths in the United States attributable to harmful drinking. METHOD: We used the etiologic-fraction method to calculate alcohol-related mortality by cause of death, using U.S. mortality data for 2000, the most recent year available. Prevalence of alcohol use was estimated from the Behavioral Risk Factor Survey and from the National Household Survey on Drug Abuse. Medium and high levels of regular drinking or heavy episodic drinking were defined as harmful drinking. RESULTS: An estimated 63,718 deaths were attributable to harmful drinking in the U.S. in 2000. Of these, an estimated 45,988 were in men and 17,730 in women, accounting for 4% of all deaths among men and 1.5% among women. Among men, 47.6% were due to medium and high levels of regular drinking, and 52.4% due to heavy episodic drinking, whereas among women these proportions were 54.2% and 45.8%. CONCLUSIONS: Harmful drinking accounts for a substantial number of deaths each year in the United States. Prevention of this underlying cause of mortality must be a public health priority.  相似文献   
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