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BACKGROUND: Studies suggest that patients who undergo off-pump coronary artery bypass grafting (OPCABG) have fewer short-term complications and use fewer inpatient resources than do patients who undergo standard coronary artery bypass grafting (CABG) with extracorporeal circulation. However, dissimilarity between groups in risk factors for complications has hindered interpretation of results. OBJECTIVES: To compare the prevalence of selected complications (atrial fibrillation, stroke, reoperation, and bleeding) and inpatient resource utilization (length of stay, discharge disposition, total charges) between subjects undergoing primary isolated CABG or OPCABG who were matched with respect to key risk factors. METHODS: Retrospective, causal-comparative survey conducted in 1 center for 18 months. Patients who underwent primary isolated CABG or OPCABG were matched for sex, age (within 2 years), left ventricular ejection fraction (within 0.05), and graft-patient ratio (exact match) and compared for prevalence of new-onset atrial fibrillation, stroke, reoperation within 24 hours, and bleeding. Statistical analysis included Wilcoxon and t tests for paired comparisons. RESULTS: The sample (107 matched pairs) was 63% male, with a mean age of 66 (SD 9.5) years, a mean left ventricular ejection fraction of 0.51 (SD 0.13), and a mean graft-patient ratio of 3.41 (SD 0.74). The 2 groups did not differ significantly in New York Heart Association class (P = .43), Acute Physiology and Chronic Health Evaluation III score (P = .22), postoperative beta-blocker use (P = .73), or comorbid conditions. None of the complications examined differed significantly between pairs. CONCLUSION: Patients with comparable risk profiles have similar prevalences of selected complications after CABG and OPCABG.  相似文献   
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Objective: To determine the effect of indwelling versus intermittent feeding tube placement on weight gain, apnea, and bradycardia in premature neonates.
Design: Eligible subjects were assigned randomly to either feeding tube method. Each subject was followed for 6 days.
Setting: The study was conducted in a secondary level neonatal intensive-care unit (NICU), a tertiary level NICU in a perinatal center, and a tertiary level NICU in a referral center.
Patients/Participants: Neonates who were 24–34 weeks gestational age, developmentally appropriate for gestational age, medically stable, on full enteral feedings through an orogastric or a nasogastric tube, and not fluid restricted. Ninety-three neonates were enrolled-49 in the indwelling group and 44 in the intermittent group. Nine neonates did not complete the study.
Interventions: Nasogastric indwelling feeding tubes were placed and left in site for up to 3 days. Orogastric intermittent feeding tubes were placed for each feeding and removed at completion of the feeding.
Main outcome measures: Weight gain, apnea, and bradycardia. Results: Members of both groups had similar demographic characteristics, clinical problems, and nutritional intake. No statistical differences were found between the two groups in weight gain or episodes of apnea and bradycardia.
Conclusions: There were no statistically or clinically significant differences between the two groups. The intermittent method of feeding is more expensive. Because no clinical differences were found, the type of tube placement chosen for feeding the premature infant may be based on economics.  相似文献   
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The various causative and mechanistic phenomena associated with aneuploidy induction require considerable investigation to better understand the etiology of chromosome missegregation. We investigated the potential of vinblastine sulfate, pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate to induce numerical and structural chromosome changes in female mouse germ cells. Superovulated ICR mice were administered the compounds either by intraperitoneal injection or oral gavage, and oocytes were collected and processed for cytogenetic analysis 17 hr later. Vinblastine sulfate, administered i.p., induced a significant increase in the frequency of ovulated Ml oocytes and of hyperploid Mll oocytes compared to controls, but did not increase the frequency of structural aberrations. Pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate did not increase the frequency of numerical or structural chromosome changes in female mouse germ cells. © 1993 Wiley-Liss, Inc.  相似文献   
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Etched track detectors are widely used for the detection of radon and its decay products. They have many desirable attributes: they are small, cheap, simple, non-toxic and non-hazardous. Etched track detectors provide adequate accuracy for most radiological protection purposes provided stringent quality assurance is maintained. The UK validation scheme provides an important component of QA but continuous monitoring of conditions and results is also needed. If these conditions are observed, these detectors provide an entirely adequate tool for large-scale use in assessing levels of radon in houses. Accurate estimates of long-term average radon levels require a measurement over several months because of the short-term fluctuations in radon concentrations.  相似文献   
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This paper identifies the need for more specific guidelines in preparing faculty to use and develop computer-based instructional materials. Cory's model for faculty development is described and planning considerations are outlined. Finally, components of this multifaceted approach to faculty development—identifying available resources, emphasizing the current uses of computers, providing computer literacy/faculty awareness sessions, focusing on the instructional use of microcomputers, collaboration, and communication—are discussed.  相似文献   
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