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In ovariectomized rhesus monkeys, the electrophysiological manifestation of luteinizing hormone-releasing hormone (LHRH) pulse generator activity was arrested by morphine and reinitiated by naloxone. These responses were noted within 1 and 2 min, respectively, after the intravenous injection of the drugs. Naloxone given alone had no effect. These results support the view that opioids modulate pulsatile gonadotropin release by an action on the hypothalamic LHRH pulse generator.  相似文献   
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Purpose  

An open-label Phase 1 study of recombinant prime-boost poxviruses targeting CEA and MUC-1 in patients with advanced pancreatic cancer was conducted to determine safety, tolerability and obtain preliminary data on immune response and survival.  相似文献   
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OBJECTIVES: Very low birth weight (VLBW) infants are vulnerable to nosocomial infections and subsequent morbidity; including infections caused by Staphylococcus aureus: 85% of nosocomial S. aureus infections are caused by capsular polysaccharide (CPS) types 5 and 8. Altastaph is a polyclonal investigational human immunoglobulin G (IgG) with high levels of opsonizing S. aureus CPS types 5 and 8 IgG. METHODS: A Phase 2 clinical trial to assess the safety and kinetics of Altastaph in VLBW infants. Neonates in this multicenter study were randomized to receive two identical 20 ml/kg i.v. infusions of either 0.45% NaCl placebo or 1000 mg Altastaph/kg. Each infant was followed for 28 days after the second infusion or until discharge. Serum S. aureus CPS types 5 and 8 IgG levels were measured preinfusion and at various times after each infusion. RESULTS: Of 206 neonates, 158 received both infusions. Adverse events were similar in the two treatment groups. Six subjects (3% in each group) discontinued owing to an adverse event. Geometric mean anti-type 5 IgG levels were 402 and 642 mcg/ml 1 day following infusion of the first (day 0) and Second (day 14) doses, respectively, in neonates < or =1000 g and slightly higher in neonates 1001 to 1500 g. Trough levels before second infusion were 188 mcg/ml. Type 8 IgG levels were similar. Geometric mean IgG levels among placebo recipients were consistently <2 and <5 mcg/ml for types 5 and 8 in both weight groups. Three episodes of S. aureus bacteremia occurred in each arm. CONCLUSIONS: Infusion of Altastaph in VLBW neonates resulted in high levels of specific S. aureus types 5 and 8 CPS IgG. The administration of this anti-staphylococcal hyperimmune globulin was well tolerated in this population.  相似文献   
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We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed.  相似文献   
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Pyretic action of low doses of gamma-hydroxybutyrate in rats   总被引:1,自引:0,他引:1  
gamma-Hydroxybutyrate (GHB) has been found to have a biphasic effect on body temperature with increased body temperature after low doses (5-10 mg/kg) and decreased body temperature after high doses (300-500 mg/kg). Brain levels of GHB between 30 and 60 min post-injection of GHB were not altered by the low doses (5-10 mg/kg), although a dose of 200 mg/kg produced a large increase in the brain concentration.  相似文献   
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The purpose of this study was to compare the attitudes toward basic sciences of students in a preclinical problem-based curriculum and a conventional lecture-based curriculum at the end of their second year of medical school. The results showed that the PBL class had more positive attitudes toward basic sciences than students in the conventional class. These results may reflect a learning environment where students meet many scientist role models as teachers and where basic science is learnt in the context of clinical problems.  相似文献   
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