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Pediatric Radiology - Stages of healing for classic metaphyseal lesions (CMLs) are not well established. Follow-up skeletal surveys provide an opportunity to evaluate signs of healing CMLs. To...  相似文献   
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This study's objective was to examine the extent to which individuals exhibit a preference for physicians based upon the race/ethnicity and gender of a physician's name. We conducted an online survey of 915 adults, who viewed a comparative display of four physicians' quality performance. We randomized the name of one physician, whose quality performance was equal to that of one physician and better than two other physicians, to be either typically African American male, African American female, white male, white female, or Middle Eastern (gender ambiguous). In regression models, participants more frequently selected the physician with the randomized name when displayed with a white male name, compared to when presented with an African American male, African American female, or Middle Eastern name (ORs ranging from .59 to .64). White and male study participants exhibited this pattern, while racial/ethnic minority participants did not. If the hypothetical choice bias observed here translates to people's actual selection of physicians, it could be a contributing factor for why women and racial/ethnic minority physicians have lower incomes than white male physicians.  相似文献   
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The objective of this study was to evaluate possible adverse effects of long-term bile acid-binding resin (cholestyramine) treatment on vitamin D, parathyroid hormone, and calcium levels in middle-aged men. A double-blind randomized clinical trial was carried out over a period of 7 to 10 years at the University of Minnesota's Lipid Research Clinic as part of the Lipid Research Clinic's Coronary Primary Prevention Trial. Two hundred and sixty-eight men aged 42 to 68 years who had been previously randomized in the CPPT to cholestyramine or placebo and who had taken at least 75% of the prescribed study medication (6 packets or 24 gm/day) as determined by packet counts for the duration of the Coronary Primary Prevention Trial including the last 4 months of the trial were studied: one group (n = 124) received cholestyramine and the other group (n = 144) received a corresponding dose of placebo. Serum samples were obtained at the time of the final study visit in cholestyramine and placebo groups. (Results are reported as mean +/- SD in SI units). There were no differences in plasma levels of calcium (2.3 +/- 0.1 mmol/L vs 2.3 +/- 0.1 mmol/L), phosphorus (0.99 +/- 0.14 mmol/L vs 0.98 +/- 0.12 mmol/L), albumin (45 +/- 3 gm/L vs 46 +/- 0.6 gm/L), calcifediol (62.6 +/- 29.2 nmol/L vs 63.4 +/- 28.4), 25(OH)D2 (14 +/- 11 nmol/L vs 12 +/- 10 nmol/L) or calcitriol (99 +/- 190 pmol/L vs 91 +/- 56 pmol/L).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Image segmentations based on maximum likelihood or maximum a posteriori analyses of object textures usually assume parametric models (e.g., Gaussian) for distributions of these features. For real images, parameter accuracy and model stationarity may be elusive, so that model-free inference methods ought to have an advantage over those that are model-dependent. Functions of the relative entropy (RE) from information theory can produce minimum error, model-free inferences, and can detect the boundary of an image object by maximizing the RE between the pixel distributions inside and outside a flexible curve contour. A generalization of the RE -- the Jensen-Rényi divergence (JRD) -- computes optimal n-way decisions and can contour multiple objects in an image simultaneously. Seed regions expand naturally and multiple contours tend not to overlap. An edge detector based on the JRD, combined with multivariate pixel segmentation, generally improved the error of the segmentation. We apply these functions to contour patient anatomy in X-ray computed tomography for radiotherapy treatment planning.  相似文献   
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Ten healthy adult men participated in a study to evaluate appropriate dosing schedules of cholestyramine to minimize its effect on the absorption of hydrochlorothiazide (HCTZ). A single 8 gm dose of cholestyramine 2 hours before or after HCTZ, 75 mg po, significantly decreased the amount of HCTZ excreted unchanged in the urine over 24 hours (Ae(0-24)) by 65% (P less than 0.01) and 26% (P less than 0.05), respectively, in four subjects. Six subjects randomly received three different schedules: control, single dose of cholestyramine 4 hours after HCTZ, and multiple doses of cholestyramine (-24, -12, and +4 hours) after HCTZ. There were no significant differences in HCTZ kinetics between the control group and the subjects who received a single dose of cholestyramine. Multiple doses of cholestyramine significantly altered HCTZ kinetics, including reductions in Ae(0-24) by 35% (P less than 0.02), AUC(0-infinity) by 32% (P less than 0.01), and Cmax by 31% (P less than 0.01). We conclude that the best dosing schedule for cholestyramine is 4 hours after HCTZ, but there will still be at least a 30% to 35% decrease in the absorption of HCTZ.  相似文献   
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The cutaneous reaction demonstrates that the culture lysate of Streptococcus scarlatinæ is approximately ten time more potent in its toxic effect than is the culture filtrate since repeated and carefully controlled human skin tests show that 0.1 cc. of a 1:2000 dilution of lysate reacts equally as well as a similar dose of a 1:250 dilution of culture filtrate (Dick''s standard skin unit). Animal tests and the human intradermal reaction clearly reveal that the toxic principle of culture filtrate (Dick''s toxin) and culture lysate (Duval-Hibbard endotoxin) are of the same nature) namely intracellular derivatives of the streptococcal cell. The in vivo prepared lysate affords a more potent antigen for the production of an antiendotoxic serum than the living, killed or culture filtrate of Streptococcus scarlatinæ. The inoculations into dogs of culture filtrate and of the "washed coccal bodies" yield strikingly different results. In those that receive filtrate no toxic effect is produced while in the ones injected with the washed coccal bodies a severe and often fatal toxemia results. The dog is highly susceptible to infection with Streptococcus scarlatinæ and also readily affected by injections of the in vivo prepared lysate. Toxic effects are produced almost immediately following the intravenous injection of lysate and death usually occurs in 24 to 48 hours from an acute hemorrhagic nephritis. Daily urinary examination shows a high percentage of albumin, large numbers of fine granular casts and quantities of macroscopic blood. A study of the kidney sections reveals an extensive glomerulonephritis. The work reported constitutes further evidence in support of our original contention that the poisonous substance of the scarlatinal streptococcus is derived from the bacterial cell set free through the dissolution of the germ plasm. The liberation of the poison in vitro occurs as the natural result of autolysis while in vivo it is produced through specific action of bacteriolysin.  相似文献   
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