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71.
OBJECTIVES: To estimate how many infants in selected high-risk subgroups would require treatment with respiratory syncytial virus immune globulin (RSV-IG) to avoid 1 hospital admission and to determine whether this is economically justified. DESIGN: Cost-benefit analysis. Data from 3 randomized controlled trials of RSV-IG are used to estimate the number needed to treat to prevent 1 hospital admission for respiratory syncytial virus infection. The threshold number needed to treat is computed according to a formula incorporating costs and benefits of RSV-IG prophylaxis. Estimates of the willingness to pay were obtained from a sample of 39 health care providers (35 physicians and 4 nurses). MAIN OUTCOME MEASURES: The number needed to treat to prevent 1 hospital admission for respiratory syncytial virus infection. The threshold number needed to treat that would balance costs with benefits. RESULTS: More than 16 (95% confidence interval, 12.5-23.8) infants would need to be treated with RSV-IG to avoid 1 hospital admission for respiratory syncytial virus infection, ranging from 63 for premature infants without chronic lung disease to 12 (confidence interval, 6.3-100.0) for infants with bronchopulmonary dysplasia. A sensitivity analysis of the costs and values of hospital admission for respiratory syncytial virus infection and RSV-IG treatment resulted in a weak recommendation against the treatment of infants with bronchopulmonary dysplasia and strong recommendations that the costs and risks of RSV-IG treatment outweigh the benefits for the combined sample of infants and premature infants without lung disease. CONCLUSIONS: The number-needed-to-treat procedures offer a method to assess evidence of treatment effects and decision rules for whether to accept treatment recommendations. Under plausible assumptions, treatment with RSV-IG is not recommended for infants without lung disease. Institutions can examine cost and benefit assumptions that best fit their own practice setting.  相似文献   
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OBJECTIVES AND STUDY DESIGN: The primary objectives of this study were to compare immunologic responses, antibody persistence, safety and varicella breakthrough rates when VARIVAX (varicella vaccine) is given at the same time as M-M-R II (measles, mumps, rubella vaccine) and TETRAMUNE (conjugate Haemophilus influenzae type b, diphtheria, tetanus and whole cell pertussis vaccine) at separate injection sites (Group A) vs. VARIVAX given 6 weeks after M-M-R II and TETRAMUNE (Group B). Six hundred nine healthy children, 12 to 23 months of age, were randomized to one of two treatment (immunization) groups (Group A and Group B). Blood for antibody titers was drawn on the day of immunization, 6 weeks after each injection and 1 year later. Local and systemic adverse reactions were recorded. Exposure and cases of varicella were documented through a 1-year follow-up period. RESULTS: Measles, mumps and rubella seroconversion rates and geometric mean titers (GMTs) were similar for both treatment groups. Varicella seroconversion rates were also similar between groups. However, varicella GMTs and percent with a varicella-protective level [> or =5.0 glycoprotein (gp) enzyme-linked immunosorbent assay (ELISA) units] did not meet the prespecified criteria for similarity were lower for Group A (GMT 10.5; 82.8% > or =5.0 gp ELISA units) than for Group B (GMT 14.5; 91.2% > or =5.0 gp ELISA units). The GMTs between groups for other antibodies were similar. At the 1-year follow-up antibody titers were comparable in both groups and breakthrough varicella cases appeared generally similar. There were fewer local adverse events (AEs) at the VARIVAX injection sites (9.8% and 2.9%, Group A and B, respectively) than at the TETRAMUNE sites (27.9% and 24.0%). Systemic AEs were not statistically different when M-M-R II was administered alone (8.6%) or concomitantly with VARIVAX (8.9%). When VARIVAX was given alone AEs were 1.8%. The rate of fever > or =102 degrees F after M-M-R II and TETRAMUNE administered together was 10.7% on Days 0 to 3 and 23.7% on Days 7 to 21. When VARIVAX was administered alone, the rate of fever was 5.4% on Days 0 to 3 (P = 0.018) and 10.8% on Days 7 to 21 (P<0.001). CONCLUSION: Because the varicella titers were comparable and varicella breakthrough rates generally similar at 1 year in both groups, we expect that the concomitant administration of VARIVAX with M-M-R II and TETRAMUNE has clinical effectiveness similar to that with VARIVAX 6 weeks after the administration of these other two vaccines. VARIVAX appears to be less reactogenic than M-M-R II and TETRAMUNE.  相似文献   
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In zebra finches, gonadal steroids activate male courtship, including singing, and also strongly modulate norepinephrine (NE) levels and turnover in brain areas regulating courtship behavior. In a previous study, systemic administration of DSP-4 caused significant decreases in courtship singing. These behavioral decrements were correlated with the degree of NE depletion in several vocal control nuclei. In the present study, we attempted to further decrease brain NE levels while minimizing systemic effects by infusing DSP-4 directly into the third ventricle. DSP-4 treatment significantly reduced NE levels in three of six vocal control nuclei and both hypothalamic nuclei sampled without significantly altering dopamine or serotonin levels in any areas. DSP-4-treated males took longer to begin singing and performed fewer song bouts and courtship displays. Interestingly, behavioral deficits were limited to courtship song displays, other behavior patterns, including female-directed behaviors like approach and follow, were unaffected by DSP-4 treatment. DSP-4 treatment appeared to affect singing behavior by causing deficits in initial attentiveness to females and initiation of singing rather than by affecting song structure.  相似文献   
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Esophageal disorders in children can result in significant morbidity. The most common esophageal disorder seen in children is gastroesophageal reflux. Other common disorders affecting the esophagus include peptic esophageal strictures, esophageal atresia with or without tracheoesophageal fistula, caustic and foreign body ingestions, achalasia, and cricopharyngeal achalasia. We discuss what is currently known about these common pediatric esophageal disorders with regard to pathophysiology, clinical presentation, and diagnostic and treatment strategies.  相似文献   
79.
A carnivore, the ferret possesses a vomeronasal organ--accessory olfactory bulb (VNO-AOB) projection to the hypothalamus; however, little is known about its function. Pheromones in soiled bedding from estrous female ferrets or an artificial peppermint odor significantly augmented nuclear Fos protein immunoreactivity (Fos-IR), a marker of neural activation, in several main olfactory bulb (MOB) sites but not in the AOB of gonadectomized male and females. Testosterone propionate (TP) significantly augmented the MOB's neuronal Fos responses to estrous females' pheromones, but not to peppermint. Estrous odors, but not peppermint, also augmented neuronal Fos-IR in the medial preoptic area (mPOA) of female, but not male, subjects. Pheromones in soiled bedding from breeding male ferrets significantly augmented neuronal Fos-IR in the MOB and in the medial amygdala of gonadectomized, TP-treated male and female subjects. Again, male pheromones failed to influence neuronal Fos-IR in the AOB of either sex, and only females showed significant increases in neuronal Fos-IR in the lateral aspect of the ventromedial nucleus and mPOA. These results point to an essential role among higher mammals of the main olfactory epithelium-MOB projection to the hypothalamus in detecting and processing pheromones. Gonadectomized ferrets showed significant increases in sniffing behavior when placed on either female or male bedding. This occurred regardless of whether they had received TP or oil vehicle, suggesting that testosterone's facilitation of neuronal Fos responses to estrous females' odors in the MOB of both sexes cannot be attributed to increased scent gathering. Androgen receptor-IR was present in the MOB granule cell layer of male and female ferrets, raising the possibility that testosterone acts directly on these cells to augment their responsiveness to pheromones.  相似文献   
80.
The ontogeny of the noradrenergic receptor subtypes modulating hypoglossal (XII) nerve inspiratory output was characterized. Noradrenergic agents were locally applied over the XII nucleus of rhythmically active medullary slice preparations isolated from mice between zero and 13 days of age (P0-P13) and the effects on XII inspiratory burst amplitude quantified. The alpha1 receptor agonist phenylephrine (PE, 0.1-10 microM) produced a dose-dependent, prazosin-sensitive (0.1-10 microM) increase in XII nerve inspiratory burst amplitude. The magnitude of this potentiation increased steadily from a maximum of 15+/-8% in P0 mice to 134+/-4% in P12-P13 mice. The beta receptor agonist isoproterenol (0.01-1.0 mM) produced a prazosin-insensitive, propranolol-sensitive potentiation of XII nerve burst amplitude. The isoproterenol-mediated potentiation increased with development from 27+/-5% in P0-P1 slices, to 37+/-3% in P3 slices and 45+/-4% in P9-P10 slices. The alpha2 receptor agonist clonidine (1 mM) reduced XII nerve inspiratory burst amplitude in P0-P3 slices by 29+/-5%, but had no effect on output from P12-P13 slices. An alpha2 receptor-mediated inhibition of inspiratory activity in neonates (P0-P3) was further supported by a 19+/-3% reduction in XII nerve burst amplitude when norepinephrine (NE, 100 microM) was applied in the presence of prazosin (10 microM) and propranolol (100 microM). Results indicate that developmental increases in potentiating alpha1 and, to a lesser extent, beta receptor mechanisms combine with a developmentally decreasing inhibitory mechanism, most likely mediated by alpha2 receptors, to determine the ontogenetic time course by which NE modulates XII MN inspiratory activity.  相似文献   
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