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1.
Quinidine gluconate 324 mg sustained release tablets (Quinaglute) was administered as a single dose to 15 healthy male subjects following an overnight fast, immediately following a high fat (HF) breakfast or immediately following a low fat (LF) breakfast. Serum samples were obtained over a 48 h period and analyzed for quinidine content using a high performance liquid chromatographic assay. Under the conditions of the study, both the rate and extent of quinidine bioavailability was significantly affected by food. The extent of bioavailability was statistically significantly greater (p less than 0.05) following both the HF and LF meals as compared to that in the fasted state. Rate of bioavailability was significantly enhanced following the LF meal as compared to that of the other two treatment groups. Although peak concentrations were greater and time to peak concentrations somewhat later following the HF meal versus those under fasting conditions, these differences were not statistically significant. In addition, the characteristics of the serum concentration-time profile (as defined by the number, magnitude, and time of occurrence of the multiple absorption maxima) was unique for each of the three treatment groups. Possible mechanisms underlying these results are explored.  相似文献   
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Chlamydia screening in primary care   总被引:1,自引:0,他引:1  
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BACKGROUND: Children with poorly controlled asthma are at high risk of airway remodeling, sleep disruption, school absenteeism, and limited participation in activities. OBJECTIVE: To determine asthma prevalence and characterize disease severity and burden in school-aged children. METHOD: A case-finding study was conducted via a multiple-choice questionnaire and asthma algorithm. Items used for analysis include physician diagnosis of asthma, symptom severity, and health care utilization. The chi2 test was used to determine the significance of differences among cases. Logistic regression was used to evaluate the association of patient factors and asthma indicators. RESULTS: Of the 5,417 children surveyed, 1,341 (25%) were classified as being at risk of asthma. Of these asthma cases, 55% were positive by diagnosis and algorithm (active), 10% were positive per algorithm alone (suspected), and 35% were positive per diagnosis alone (nonactive). Only 14% of all asthma cases reported experiencing no respiratory symptoms (< 1% active, 2% suspected, and 40% nonactive) compared with 75% of noncases. Also, 75% of noncases reported never missing school compared with 19%, 33%, and 54% of active, suspected, and nonactive asthma cases. African American race, Medicaid enrollment, and male sex were independent predictors of asthma risk. Similarly, African American race, Medicaid enrollment, age, and persistent asthma were independent predictors of emergency department use among asthma cases. DISCUSSION: Prevalence of active symptoms suggestive of poor asthma control was extremely high among urban, minority children enrolled in Arkansas' largest public school district. Poor asthma control greatly affects quality of life, including school attendance and performance. Interventions should raise expectations and emphasize the importance of achieving asthma control.  相似文献   
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Partial k-space sampling is frequently used in single-shot diffusion-weighted echo-planar imaging (DW-EPI) to reduce the TE and thereby improve the SNR. However, it increases the sensitivity of the technique to bulk rotational motion, which introduces a phase gradient across the tissue that shifts the echo in k-space. If the echo is displaced into the high spatial frequencies, conventional homodyne reconstruction fails, causing intensity oscillations across the image. Zero-padding, on the other hand, compromises the image resolution and may cause truncation artifacts. We present an adaptive version of the homodyne algorithm that detects the location of the echo in k-space and adjusts the center and width of the homodyne filters accordingly. The adaptive algorithm produces artifact-free images when the echo is shifted into the high positive k-space range, and reduces to the standard homodyne algorithm in the absence of bulk motion.  相似文献   
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The role of the neuroendocrine environment in the pathogenesis of enteric bacterial infections is increasingly being recognized. Here we report that norepinephrine augments Escherichia coli O157:H7-induced intestinal inflammatory and secretory responses as well as bacterial adherence to intestinal mucosa in a bovine ligated ileal loop model of infection. Norepinephrine modulation of enteritis and adherence was dependent on the ability of E. coli O157:H7 to form attaching and effacing lesions.  相似文献   
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A cross-sectional survey of contraceptive practices was conducted among 180 South Asian women aged 16 to 50 years, attending inner-city general practices. Overall prevalence of contraceptive use was 63% and ranged from 70% in South Asian teenagers, to only 50% in women over 30 who had completed their family. Thirteen per cent of women had had a termination of pregnancy Although contraceptive use in this group is increasing, it has not yet reached national levels.  相似文献   
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