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OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
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OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
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OBJECTIVE: This study aims to establish normal values for nucleated red blood cells in term singletons and factors associated with their elevation.STUDY DESIGN: Cord blood was prospectively collected from term singleton gestations from Feb. 1 to July 31, 1995. Umbilical vein white blood cells and nucleated red blood cells were counted and umbilical arterial pH was determined. Medical records provided maternal and neonatal information.RESULTS: Cord blood from 1112 cases was obtained and evaluated for nucleated red blood cells per 100 white blood cells. Nine outliers were censored (nucleated red blood cells per 100 white blood cells = 126 to 830); five cases were excluded because of missing data. The mean value of nucleated red blood cells per 100 white blood cells was 8.55, the SD was 10.27, and the range was 0 to 89. The value did not vary by maternal tobacco or drug use, anemia, fetal presentation, or mode of delivery. Both maternal diabetes and meconium were associated with elevated values, p < 0.01. Apgar scores and cord pHs showed trends toward inverse proportionality to the number of nucleated red blood cells per 100 white blood cells.CONCLUSION: The mean number of nucleated red blood cells per 100 white blood cells was 8.55, with a wide range and SD. Elevated values may be associated with markers of intrauterine hypoxia such as meconium, lower Apgar scores, and lower pH values. (Am J Obstet Gynecol 1997;176:1149-56.)  相似文献   
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Stillbirth occurs in nearly 1% of all births in the USA, and is one of the most common but least studied adverse pregnancy outcomes. The many risk factors for and causes of stillbirth are presented. Over the past several decades, the rate of stillbirth has been substantially reduced, with the reduction most apparent in those stillbirths previously occurring at term and/or in labor. Reductions have occurred because of reductions in risk factors (i.e. prevention of Rh disease and better control of diabetes), better antepartum monitoring of those with risk factors followed by early delivery for those fetuses found to be at risk (i.e. growth restriction, maternal pre-eclampsia), better intrapartum fetal monitoring, increases in Cesarean section for those at risk, and early detection of congenital anomalies followed by termination prior to the time that these early fetal deaths are classified as stillbirths. Finally, the value of using fetal autopsy and placental examination to determine the cause of death accurately, both for research purposes and for patient counseling in future pregnancies, is explored.  相似文献   
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Richards  H.  L.  Ray  D.  W.  Kirby  B.  C.E.M.  Griffiths  刘艳 《世界核心医学期刊文摘》2006,2(3):36-36
背景:应激可能会触发和(或)加重一些银屑病患者的病情。目的:下丘脑-垂体-肾上腺(HPA)轴的激活是有效应激反应的关键,本文以银屑病患者为对象研究此关系。方法:40例慢性斑块型银屑病患者与40例年龄匹配的正常对照者,随机经历3种急性心理应激(认知、情感与社会应激)。在基线时及每次应激后,连续检测血浆皮质激素、脉率和血压。在检测日9:00,收集唾液皮质激素标本。结果:对照者经历社会应激后,脉率与血浆皮质激素水平显著相关(r=0.38;P〈0.05);而银屑病患者则无此联系(r=0.07;无显著性)。  相似文献   
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