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The human immunodeficiency virus is notorious for its ability to evade the immune system. As well as its ability to escape from cell-mediated and humoral immune responses, new insights are detailing its subversive, pernicious interactions with the innate immune system. The molecular mechanisms underlying these processes highlight potential therapeutic and vaccination strategies.  相似文献   
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Tobacco use by university students,Lebanon, 2001   总被引:2,自引:0,他引:2  
Aims The objective was to determine the prevalence of smoking [cigarettes and/or narghile (i.e. water‐pipe)] among university students and to examine multiple correlates. Design Cross‐sectional. Setting Beirut, Lebanon. Participants A proportionate random sample of 1964 students from public and private universities in Beirut, Lebanon. Measurements Participants completed a self‐administered anonymous questionnaire that included demographic and scholastic items and health behavioral aspects, including smoking, alcohol, physical activity, weight control measures and seat belt use. Findings The overall prevalence of smoking was 40% (21.1%, 7.6% and 11.3% of the students were smoking only narghile, only cigarettes and both cigarettes and narghile, respectively). Regression analyses showed that males, those of non‐Lebanese origin, pursuing undergraduate degrees, performing risky weight control measures and drinking excessive amounts of alcohol had increased odds of smoking cigarettes. Also, age, high level of paternal education and field of study were significant predictors. Narghile smoking was significantly higher among males who drank excessive alcohol. Conclusions The authors advocate a collaborative effort to alleviate the consequences of smoking among university students.  相似文献   
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Consanguinity, marriage between relatives, has been associated with perinatal mortality and morbidity. Apnea of prematurity is defined as the cessation of breathing for longer than 20 seconds or that of any duration if accompanied by cyanosis and sinus bradycardia, for infants born before 37 weeks of gestation. The objective of the study was to examine the association between consanguinity and apnea of prematurity in Greater Beirut, an area having a relatively high prevalence rate of consanguineous marriages. The study was cross-sectional. Between September 1, 1998, and March 31, 2001, 21723 newborn infants were admitted to the National Collaborative Perinatal Neonatal Network in Greater Beirut, Lebanon. The inclusion criteria were infants less than 37 weeks of gestation who were admitted to the intensive care unit, with no congenital malformations, sepsis, or neurologic disorders. Analysis was based on 597 infants of whom 66 had apnea of prematurity. With adjustment for weeks and type of gestation, pregnancy complications, and Apgar score, the odds ratio of apnea of prematurity for first-degree consanguineous parents as compared with other marriages was 2.9 (95% confidence interval: 1.3, 6.4). In addition to the recognized etiologic factors for apnea of prematurity, this study suggests a role played by genetic factors.  相似文献   
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ABSTRACT: Background: Obstetric practice has witnessed a worldwide trend of increasing cesarean section rates in recent years. Similar trends have been observed in Lebanon, according to 2 studies conducted in 1996 and 1999. The objective of the present study was to assess the differences in predictors of cesarean delivery among nulliparous women in a “control hospital” with a low cesarean delivery rate (12.5%) and the rest of the National Collaborative Perinatal Neonatal Network (NCPNN) “study hospitals” with a higher cesarean delivery rate (31.4%). Methods: Data were collected by the NCPNN database, which covers deliveries at 9 major hospitals located in the Greater Beirut area. Data analysis was performed on the 6,668 consecutive deliveries occurring between January 1, 2001, and December 31, 2002, at the NCPNN participating centers. The questionnaires included items that cover parental sociodemographic characteristics and maternal and newborn health characteristics. Sources of data included direct interviews with mothers after delivery and before hospital discharge and reviews of obstetric and nursery medical charts. Chi‐square tests and t tests were performed for categorical and continuous clinical predictors of cesarean section. Logistic regression was performed to determine the odds of having a cesarean section for the study hospitals when compared with the control hospital. Odds ratios and 95% confidence intervals are reported. Results: Variables in the study hospitals that correlated with a higher cesarean delivery rate were male obstetricians, day of the week, and mode of payment compared with the control hospital. Conclusions: In a country with a high cesarean section rate, 1 hospital met World Health Organization criteria for acceptable cesarean section rates, with no compromise in neonatal outcome. Further studies are needed to investigate potential policies to decrease the high cesarean section rate. (BIRTH 34:1 March 2007)  相似文献   
78.
BACKGROUND: Obese patients may be sensitive to the respiratory depressant effect of opioid analgesics. Alternative methods for analgesia may be beneficial for management of bariatric surgery. We evaluated the effect of dexmedetomidine on anesthetic requirements during surgery, hemodynamic, recovery profile and morphine use in the postoperative period. METHODS: Eighty adult patients scheduled for elective laparoscopic Roux-en-Y gastric bypass surgery were randomly assigned to one of two study groups; Group D (40 patients) received dexmedetomidine (0.8-microg/kg bolus, 0,4 microg kg(-1) h) and Group P (40 patients) received normal saline (placebo) in the same volume and rate. Intraoperative and postoperative mean blood pressure and heart rate were recorded. The total amount of intraoperative fentanyl and propofol required to maintain anesthesia were measured. Recovery profile, pain score and total amount of morphine used via patient controlled analgesia (PCA) were assessed. RESULTS: During surgery, dexmedetomidine decreased the total amount of intraoperative fentanyl and propofol required for maintenance of anesthesia compared to placebo. Patients who received dexmedetomidine showed significant decrease of intraoperative and postoperative mean blood pressure, heart rate. In the postoperative period, dexmedetomidine decreased pain scores and PCA morphine use significantly and showed better recovery profile as compared to the placebo Group. There was no difference in the incidence of postoperative nausea and vomiting (PONV) between both groups. CONCLUSION: The intraoperative infusion of dexmedetomidine decreased the total amount of propofol and fentanyl required to maintain anesthesia, offered better control of intraoperative and postoperative hemodynamics, decreased postoperative pain level, decreased the total amount of morphine used and showed better recovery profile compared with placebo.  相似文献   
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Objectives:

To evaluate the clinical and biochemical characteristics of children with diabetic ketoacidosis (DKA).

Methods:

In this retrospective study conducted between June 2012 and November 2013 at the King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia, we evaluated pediatric DKA admissions from 1995-2008 (Phase 1). From the case files, we obtained information related to patients’ age, gender, weight, presenting complaints, serum biochemical profile, and management.

Results:

This study included 373 DKA admissions with a median age of 11 years (interquartile range [IQR]:8-13). The patients in the subgroup of age more than 10 years old had the highest proportion of admissions (n=250, 67%, p<0.000). The median duration of diagnosis of diabetes mellitus (DM) was 3 years (IQR:2-6). New-onset DM was 47%. Predominant precipitating cause was acute illness, mostly viral syndrome in 22% of all cases, and non-compliance to insulin regimen was in 79% of the diagnosed diabetic cases. Blood glucose, pH, anion gap, serum osmolality, serum potassium, and serum phosphate showed the highest change during the initial 6 hours of management, while trends of serum bicarbonate and blood urea nitrogen demonstrated a predominant change in the initial 12 hours.

Conclusion:

The notable findings in this study, such as, higher mean age of presentation, high rate of non-compliance to insulin as the cause of precipitation, and a high prevalence of abdominal pain at presentation should be followed up with further comparative studies.Diabetes mellitus (DM) is an endocrine disease affecting millions of children worldwide.1-3 Diabetic ketoacidosis (DKA) is one of the serious complication of diabetes in the pediatric population,4 and its prevalence increases by an annual rate of 3% worldwide.3 It is associated with significant risk of life threatening complications.5-8 The criteria for diagnosis of DKA in children by the International Society for Pediatric and Adolescent Diabetes describes DKA as blood glucose >11 mmol/L, venous pH <7.3, or bicarbonate <15 mmol/L, and ketonemia with ketonuria.9 Previous studies1,2 have reported characteristics of DKA patients based on different geographical areas. Overall, there is a paucity of literature on this particular aspect. The aim of this study was to assess pediatric patients presenting with DKA regarding aspects of demographics, presentation, investigations, and management in the Kingdom of Saudi Arabia (KSA).  相似文献   
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