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71.
The purpose of this study was to evaluate non-contrast magnetic resonance imaging (MRI) findings of adhesive capsulitis and correlate them with clinical stages of adhesive capsulitis. This will hopefully define a role for shoulder MR imaging in the diagnosis of adhesive capsulitis as well as in potentially directing appropriate treatment. Forty-seven consecutive non-contrast magnetic resonance imaging examinations of 46 patients with a clinical diagnosis of adhesive capsulitis were retrospectively reviewed and correlated with clinical staging. Specific MRI criteria correlated with the clinical stage of adhesive capsulitis, including the thickness and signal intensity of the joint capsule and synovium as well as the presence and severity of scarring in the rotator interval. Routine MRI of the shoulder without intraarticular administration of gadolinium can be used to diagnose all stages of adhesive capsulitis, including stage 1, where findings may be subtle on clinical examination. We believe that future studies assessing the role of MRI in guiding the initiation of appropriate treatment should be undertaken.  相似文献   
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Experimental and epidemiologic studies suggest that vitamin D metabolites (1,25-dihydroxyvitamin D [1,25(OH)(2)D] and its precursor 25-hydroxyvitamin D [25(OH)D]) may reduce breast cancer risk. We examined subsequent breast cancer risk related to serum levels of these metabolites. In a cohort of women ages 55 to 74 years, who donated blood at baseline (1993-2001) in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, we identified 1,005 incident breast cancer cases during follow-up through 2005 (mean time between blood draw and diagnosis, 3.9 years). Noncases (n = 1,005) were frequency matched to the cases based on age and year of entry. Sample weights that accounted for unequal probabilities of selecting cases and noncases were applied to make inferences that reflected the entire Prostate, Lung, Colorectal, and Ovarian cohort. Using Cox proportional hazards modeling, we computed breast cancer relative risks (RR) and 95% confidence intervals (95% CI) by quintile for each metabolite. The RR of breast cancer for the highest quintile of 25(OH)D concentration versus the lowest was 1.04 (95% CI, 0.75-1.45; P(trend) = 0.81). Similarly, the breast cancer RR for the highest quintile of 1,25(OH)(2)D compared with the lowest was 1.23 (95% CI, 0.91-1.68; P(trend) = 0.14). Excluding the first 2 years of follow-up did not materially alter these estimates. There was also no evidence of inverse risk in older women (> or =60 years) versus younger women (<60 years). In this prospective study of postmenopausal women, we did not observe an inverse association between circulating 25(OH)D or 1,25(OH)(2)D and breast cancer risk, although we cannot exclude an association in younger women or with long-term or earlier exposure.  相似文献   
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Serum osteocalcin (Gla) and skeletal alkaline phosphatase (SAP) concentration both reflect osteoblast activity in the dynamic process of bone formation. To assess the relation in premature infants between change in bone mineral content (BMC) and both Gla and SAP serum concentration, we longitudinally measured BMC via photon absorptiometry and serum Gla and SAP concentration from birth to 16 wk in 20 very low birth weight infants. Serum total calcium, phosphorus, parathyroid hormone, and vitamin D metabolite concentrations were also monitored. All serum values were measured in the 20 mothers at delivery. Cord blood Gla concentrations were significantly (p less than 0.03) greater than maternal levels, and by 1 wk had significantly (p less than 0.001) increased from birth values. Total calcium, parathyroid hormone, phosphorus, and vitamin D concentrations remained in the normal range throughout the study. The increase in serum Gla concentrations, birth to 1 wk, were significantly correlated with the simultaneous increase in 1,25-dihydroxyvitamin D concentrations. The correlation between the change in BMC, however, over the first 4 mo of life and both Gla and SAP serum concentrations failed to reach statistical significance. Finally, a significant (p less than 0.003) negative correlation was measured between serum Gla and SAP concentrations at wk 4, and, although not significant, a consistently negative correlation was measured from 1-16 wk of age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
Because the efficiency of vitamin D absorption or hepatic uptake and 25-hydroxylation appears decreased in very premature infants, the routine use of 25-hydroxycholecalciferol (25-OHD3) supplementation has been suggested. Absorption studies of a 3 micrograms/kg orally administered dose of 25-OHD3 showed peak serum 25-hydroxyvitamin D2 and -vitamin D3 (25-OHD) concentrations at 4 to 8 hours similar in timing but of lesser magnitude to those seen in adults. Administration of 1 microgram/kg birth weight/day of 25-OHD3 corrected moderately low, but not very low serum (25-OHD) concentrations, and 2 micrograms/kg BW/day resulted in rapid and sustained increase in serum 25-OHD. Administration of 800 IU ergocalciferol (D2) also produced significantly higher serum 25-OHD concentrations than those in infants given 400 IU vitamin D2, but increases in serum 25-OHD were more gradual than in infants given 25-OHD3. In treatment trials with infants weighing less than 1500 gm, those given 800 IU D2, compared with those given 400 IU D2, had higher serum calcium concentrations and less frequent moderate or severe hypomineralization. Infants given 2 micrograms/kg BW 25-OHD3 had a significant increase in serum phosphorus values, but a decrease in serum calcium and magnesium concentrations, and parathyroid hormone also was suppressed to low normal values. The frequency of moderate to severe hypomineralization remained the same as in infants given 400 IU D2. In a subgroup of infants, serum 1,25-dihydroxyvitamin D was elevated over adult values, both in infants given 25-OHD3 (68.5 +/- 8.4 pg/ml) and in infants given vitamin D2 (60 +/- 6.7 pg/ml). Serum vitamin D concentrations were undetectable in four of six infants receiving 25-OHD3, but were elevated (5 to 31 ng/ml) in four infants receiving vitamin D2. Although 800 to 1000 IU D2 can be recommended as routine vitamin D supplementation in very premature infants fed standard formula, the use of 25-OHD3 requires further study.  相似文献   
78.
BACKGROUND: Recent reports of rickets among African American children drew attention to the vitamin D status of these infants and their mothers. African American women are at higher risk of vitamin D deficiency than are white women, but few studies have examined determinants of hypovitaminosis D in this population. OBJECTIVE: We examined the prevalence and determinants of hypovitaminosis D among African American and white women of reproductive age. DESIGN: We examined 1546 African American women and 1426 white women aged 15-49 y who were not pregnant and who participated in the third National Health and Nutrition Examination Survey (1988-1994). Hypovitaminosis D was defined as a serum 25-hydroxyvitamin D concentration < or =37.5 nmol/L. Multiple logistic regression was used to examine the independent association of dietary, demographic, and behavioral determinants of hypovitaminosis D. RESULTS: The prevalence of hypovitaminosis D was 42.4 +/- 3.1% ( +/- SE) among African Americans and 4.2 +/- 0.7% among whites. Among African Americans, hypovitaminosis D was independently associated with consumption of milk or breakfast cereal <3 times/wk, no use of vitamin D supplements, season, urban residence, low body mass index, and no use of oral contraceptives. Even among 243 African Americans who consumed the adequate intake of vitamin D from supplements (200 IU/d), 28.2 +/- 2.7% had hypovitaminosis D. CONCLUSIONS: The high prevalence of hypovitaminosis D among African American women warrants further examination of vitamin D recommendations for these women. The determinants of hypovitaminosis D among women should be considered when these women are advised on dietary intake and supplement use.  相似文献   
79.
BACKGROUND: Patients have been shown to be at greater risk for deep venous thrombosis, particularly proximal thrombosis, after total hip arthroplasty. Proximal thrombi are more likely to develop into pulmonary emboli than are distal thrombi. The purpose of this randomized, prospective study was to compare the prevalence of pelvic and proximal lower-extremity deep venous thrombosis after primary total hip arthroplasty between patients treated with an impulse mechanical compression device for prophylaxis and those treated with prophylactic stockings. METHODS: One hundred patients were evaluated, with use of magnetic resonance venography, for proximal deep venous thrombosis after total hip arthroplasty. Fifty patients were treated with a mechanical compression device on both lower extremities, and the other fifty patients received only prophylactic stockings. Both groups of patients received hypotensive epidural anesthesia and 325 mg of aspirin twice a day. RESULTS: Overall, proximal deep venous thrombi were found in 15% of the 100 patients. Of the fifty patients treated with mechanical compression, 8% (four) had a positive venogram. Of the fifty control patients, 22% (eleven) had a positive venogram (p < 0.05). However, overall the rate of occlusive thrombi was 6% (six) compared with an overall rate of nonocclusive thrombi of 9% (nine). The rate of occlusive thrombi was 2% (one of fifty) in the study group and 10% (five of fifty) in the control group (p = 0.04). CONCLUSIONS: On the basis of this study, we concluded that patients managed with total hip arthroplasty benefit from a reduction in the rates of femoral and pelvic deep vein thrombosis when they are treated with hypotensive epidural anesthesia, mechanical compression, and aspirin and are subsequently assessed with magnetic resonance venography.  相似文献   
80.
Hollis S 《Statistics in medicine》2002,21(24):3823-3834
Many clinical trials are analysed using an intention-to-treat (ITT) approach. A full application of the ITT approach is only possible when complete outcome data are available for all randomized subjects. In a recent survey of clinical trial reports including an ITT analysis, complete case analysis (excluding all patients with a missing response) was common. This does not comply with the basic principles of ITT since not all randomized subjects are included in the analysis. Analyses of data with missing values are based on untestable assumptions, and so sensitivity analysis presenting a range of estimates under alternative assumptions about the missing-data mechanism is recommended. For binary outcome, extreme case analysis has been suggested as a simple form of sensitivity analysis, but this is rarely conclusive. A graphical sensitivity analysis is proposed which displays the results of all possible allocations of cases with missing binary outcome. Extension to allow binomial variation in outcome is also considered. The display is based on easily interpretable parameters and allows informal examination of the effects of varying prior beliefs.  相似文献   
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