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101.
Background. The 1999 American Thoracic Society methacholine challenge guidelines stated that the 5-breath dosimeter method of methacholine administration is similar to the 2-minute tidal breath method. Recent data has disputed this assertion. We examined the differences in the diagnosis of asthma using these two methods. Methods. Data were abstracted from a prospectively generated pulmonary function database over 4 years. During the first 2 years the 5-breath dosimeter method was used, and the subsequent 2 years the 2-minute tidal breath method was used. The effect of the delivery technique was assessed by crude and adjusted odds ratios, controlling for known confounders and group differences. Results. A total of 907 subjects underwent methacholine challenge testing during the 4-year study period: 19.3% of the subjects tested with the 5-breath dosimeter method and 31.2% of those tested with the 2-minute tidal breathing method had a PC20 ≤ 8.0 mg/mL (OR 1.90, 95% CI 1.4 to 2.58, p < 0.001). The ability to reliably exclude airway hyper-responsiveness (PC20 > 16.0 mg/mL) was also altered by the differences between the testing techniques. Using the 5-breath dosimeter method, 72.4% of subjects were ruled out for airway hyper-responsiveness, whereas only 59.9% of subjects were ruled out with the 2-minute tidal breathing technique (p < 0.001). Conclusion. The two recommended protocols for the diagnosis of asthma are not equivalent and significantly alter the rate of diagnosis of asthma as well as the severity. The differences were seen across all PC20 levels, from those with strongly positive tests (PC20 ≤ 1.0 mg/mL) as well as those with negative tests for airway hyper-responsiveness (PC20 > 16.0 mg/mL).  相似文献   
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Many different agents are known to cause nonbacterial pneumonias, but the clinical findings may not vary. An understanding of the epidemiology and pathogenesis of these infections—as well as the possible etiologic agents—is important in diagnosis, prevention, and treatment. Although treatment is now mainly symptomatic, new antiviral agents will soon be available for specific therapy.  相似文献   
103.
Prospectus     
To help you save time in identifying those meetings and courses of greatest interest to you, POSTGRADUATE MEDICINE offers this objectively rated listing as a regular reader service. Each event has been rated on the factors that matter most to you: relevance of the subject to primary care, number of credit hours, cost per credit hour (registration fee only), sponsorship, and meeting site. One to four stars are awarded on the basis of the combined score for these factors.

For listing, information is needed well in advance of the event (preferably four months). Address correspondence to: Prospectus Editor, Editorial Department, POSTGRADUATE MEDICINE, 4530 W 77th St, Minneapolis, MN 55435.  相似文献   
104.
Pelvic lesions which require surgical treatment are primarily inflammatory, neo-plastic or mechanical, or a combination of any of these types. Surgery is recommended for conditions such as certain benign ovarian tumors, hydrosalpinx, ectopic pregnancy, large uterine fibroids, etc. Surgery is not advisable in such conditions as corpus luteum cysts and acute salpingitis or postabortal inflammatory disease.  相似文献   
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Background: Optimal methods of preparing students for high-stakes standardized patient (SP) examinations are unknown. Purposes: The purpose is to compare the impact of two formats of a formative SP examination (Web-based vs. in-person) on scores on a subsequent high-stakes SP examination and to compare students' satisfaction with each formative examination format. Methods: Clustered randomized trial comparing a Web-based module versus in-person formative SP examination. We compared scores on a subsequent high-stakes SP examination and satisfaction. Results: Scores on the subsequent high-stakes SP examination did not differ between the two formative formats but were higher after the formative assessment than without (p < .001). Satisfaction was higher with the in-person than Web-based formative assessment format (4.00 vs. 3.62 on a 5-point scale, p = .01). Conclusions: Two formats of a formative SP examination led to equivalent improvement in scores on a subsequent high-stakes examination. Students preferred an in-person formative examination to online but were satisfied with both.  相似文献   
107.
Minorities are underenrolled in clinical research trials, and one‐third of trials are underenrolled overall. The role of payment has not been studied at the national level as an explanation for enrollment patterns. Our objective was to examine the distribution of self‐reported previous research participation across different sociodemographic groups; to assess the public''s perception of fair payment for a low‐risk medicine trial and the association between requested payment and sociodemographic characteristics; to estimate the amount of payment for a medication trial to achieve proportional representation of minorities and different socioeconomic groups. This was a cross‐sectional study with nationally representative data collected in 2011 by the C.S. Mott Children''s Hospital National Poll on Children''s Health. To determine the relationship between perceived fair payment and individual‐level characteristics, we used multivariable linear regression.With 60% participation rate, in a sample of 2,150 respondents 11% (n = 221) of the sample had previously participated in medical research. Requested payment differed significantly by racial/ethnic group with Hispanics requesting more payment than non‐Hispanic whites (0.37 [95%CI 0.02, 0.72]) In contrast to payment at $49, $149, and $249, payment at $349 yielded proportional representation of racial/ethnic minority groups.Hispanics requested higher payment for research participation, suggesting a possible explanation for their underenrollment.  相似文献   
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