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21.
BACKGROUND: Olopatadine, an antihistamine used in allergic conjunctivitis, is under development as a nasal preparation for the treatment of allergic rhinitis. OBJECTIVES: To evaluate the efficacy of olopatadine in suppressing symptoms and biomarkers of the immediate reaction induced by nasal allergen provocation and to compare olopatadine with azelastine in the same model. METHODS: The study was approved by the Johns Hopkins University institutional review board, and all subjects gave written consent. We studied 20 asymptomatic subjects with seasonal allergic rhinitis. The study had 2 randomized, double-blind, placebo-controlled, crossover phases that evaluated 2 concentrations of olopatadine, 0.1% and 0.2%. In a third exploratory phase, olopatadine, 0.1%, was compared with topical azelastine, 0.1%, in a patient-masked design. Efficacy variables were the allergen-induced sneezes, other clinical symptoms, and the levels of histamine, tryptase, albumin, lysozyme, and cysteinyl-leukotrienes (third study only) in nasal lavage fluids. RESULTS: Both concentrations of olopatadine produced significant inhibition of all nasal symptoms, compared with placebo. Olopatadine, 0.1%, inhibited lysozyme levels, but olopatadine, 0.2%, inhibited histamine, albumin, and lysozyme. The effects of olopatadine, 0.1%, were comparable to those of azelastine, 0.1%. CONCLUSIONS: Olopatadine, at 0.1% and 0.2% concentrations, was effective in suppressing allergen-induced nasal symptoms. At 0.2%, olopatadine provided evidence suggestive of inhibition of mast cell degranulation.  相似文献   
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Previous recommendations for the use of thyroid function tests to diagnose patients with possible hypothyroidism have discounted the value of a total thyroxine (T4) test because many clinically hypothyroid patients have T4 levels that fall within the “normal” range. The authors examined the predictive value of a total T4 measurement in the evaluation of ambulatory general medical patients suspected of having hypothyroidism. Pregnant patients and those who were taking medications that interfere with thyroid homeostasis were excluded. Simultaneous T4 and thyrotropin (TSH) tests of 93 consecutive outpatients suspected to have hypothyroidism but found to be euthyroid and 27 patients discovered to be hypothyroid (TSH>10 μU/ml) were examined. A T4 of 7.0 μl/dl or less had a sensitivity of 93% with a false-positive rate of 19%. A T4 greater than 8.0 μg/dl appeared to exclude hypothyroidism (negative posttest probability of 100%). It may be possible to achieve cost savings without loss of diagnostic accuracy by using a single total T4 measurement for the initial evaluation of suspected hypothyroidism in selected outpatients. Received from the Department of Medicine, General Medicine Unit. University of Rochester School of Medicine and Dentistry, Rochester, New York.  相似文献   
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Background

 Under the Affordable Care Act, Medicaid expansion effective 1 January 2014 aimed to increase access to health care. We sought to determine the association of Medicaid expansion with disparities in utilization of breast reconstruction.

Methods

Non-Hispanic Black (NHB) and White (NHW) breast cancer patients undergoing mastectomy +/? reconstruction between 2010 and 2017 were selected from the National Cancer Database. Annual trends for utilization of breast reconstruction by race, income, and education were evaluated by Medicaid expansion status using difference-in-differences regression analyses. Medicaid expansion was categorized by expansion date as early (2010–2013), 2014 (1/2014), late (after 1/2014), or no expansion.

Results

Of 443,607 patients, 36.3% (n = 161,128) underwent reconstruction, 13.1% (n = 58,249) were NHB, 16.8% (n = 74,430) had median income < $40,227, and 17.1% (n = 75,718) were in the lowest education quartile. In non-expansion states, lower proportions of NHB patients underwent reconstruction than NHW patients in all years, with the smallest disparity (NHB% ? NHW%) (? 6.4%) in 2017. Decreases in disparities between NHB and NHW patients were seen with the smallest difference observed in 2014 (? 2.5%) in early-expansion states, in 2017 (? 0.7%) in 1/2014 expansion states, and in 2017 (? 4.5%) in late-expansion states. Similar findings for convergence of reconstruction utilization rates for the lowest two education levels and lowest two income quartiles were found with Medicaid expansion, with no convergence seen in non-expansion states over the study period.

Conclusions

Some improvement in breast reconstruction disparities followed Medicaid expansion. Failure to improve parity without Medicaid expansion should be a consideration with any modifications to Medicaid access.

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Water-suppression MRI: role in the evaluation of osseous lesions   总被引:1,自引:0,他引:1  
The efficacy of chemical shift based water-suppression MRI in the evaluation of bone marrow lesions has not been previously reported. T1-weighted images without and with water suppression were compared in five patients with 16 lesions. There was a significant improvement in the contrast-to-noise ratio (from 4.32 to 5.95, P < 0.01) and contrast ratio (from 1.71 to 5.69, P < 0.004) with water suppression. Water suppression may be useful clinically by increasing the conspicuity of bone marrow lesions.  相似文献   
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PURPOSE OF THE PAPER: The purpose of this paper is to test if the previously identified disparity in mortality rates among full Hawaiians, part Hawaiians, and non­Hawaiians in the state of Hawaii has continued into the 1990s. SUMMARY OF METHODS UTILIZED: Based on Hawaii vital records and population data, standardized age­specific mortality rates by cause and 95% confidence intervals were estimated. PRINCIPAL FINDINGS: The most striking finding was the significant differences in mortality rates in four age strata ­­ 45­54, 55­64, 65­74, and 75­84 ­­ with mortality rates highest for full Hawaiians, lowest for non­Hawaiians, and intermediate for part Hawaiians. CONCLUSIONS: Findings suggest that Native Hawaiians continue to be at greater risk of death compared with non­Hawaiians, with full Hawaiians at greatest risk. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS: Asian and Pacific Islander Americans have been called the model minority. These data provide evidence that Native Hawaiians, especially full Hawaiians, have dramatically higher mortality rates than non­Hawaiians and merit special attention.  相似文献   
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The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2). Measurements of SpO2 were taken at 1, 5, 10 min, and 24 hr after delivery. At one and five minutes, SpO2 recorded from the right hand was higher than that recorded from the lower extremities (71.9% +/- 6.5% vs 63.4% +/- 4.3% and 83.3% +/- 4.2% vs 76% +/- 4.1%, mean +/- SD, respectively). At ten minutes these differences diminished, and had almost completely disappeared after 24 hr. These results can be explained by the presence of R-L shunting at the ductus arteriosus level, producing reduced SaO2 in the lower extremities. Oxygen saturation did not differ between neonates delivered vaginally or by Caesarean section, regardless of the presence or type of anaesthesia. We concluded that neonates remain relatively desaturated in the immediate postpartum period and that the SpO2 obtained from the right hand is a better index of neonatal oxygenation than that obtained from the heel.  相似文献   
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