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51.
E F Ellerbeck J A Lewis D Nalin K Gershman W J Miller M E Armstrong J P Davide A E Rhoad B McGuire G Calandra 《Vaccine》1992,10(10):668-672
To determine the safety and immunogenicity of an inactivated hepatitis A vaccine, 56 healthy adult volunteers were randomly assigned to receive an intramuscular injection of 6.3, 12.5 or 25 ng of inactivated hepatitis A vaccine or placebo at 0, 2 or 4, and 24 weeks. Adverse reactions occurred with similar frequency in vaccine and placebo recipients and consisted primarily of pain or tenderness at the injection site. By 4 weeks after a single 6.3, 12.5 or 25 ng injection, seven, nine and ten out of ten vaccinees, respectively, had antibody detectable by a HAV AB assay modified to increase its sensitivity tenfold. All vaccinees had antibodies detectable by this assay within 2 weeks of their second inoculation. Geometric mean antibody levels increased with higher doses of vaccine (p = 0.05). Neutralizing antibody was detected within 4 weeks of a single inoculation in all vaccinees. Neutralizing antibody was detected after the third inoculation at dilutions of greater than or equal to 1:2048 in all 12.5 and 25 ng vaccinees. All 19 vaccinees tested at 24 months still had HAV antibodies detectable by a modified HAV AB assay. This inactivated hepatitis A vaccine appears to be well tolerated and immunogenic at doses of 6.3-25 ng. The choice of dose and vaccination schedule may depend on the rapidity with which seroconversion is desired. 相似文献
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Genomic in situ hybridization (GISH) successfully differentiated homoeologous genomes in the interspecific hybrid Allium cepa × fistulosum, thus allowing the detection of reciprocal crossover events as label exchanges in separating anaphase I chromosomes. Three of the eight chromosome pairs were positively identified by fluorescence in situ hybridization (FISH) to rDNA sequences. There was a general similarity of the GISH-based label exchange frequencies and metaphase I chiasma frequencies, but with a 20% deficit of chiasmata. Reasons for this apparent deficit are discussed. The locations of chiasmata and label exchanges are in broad agreement. 相似文献
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Kevin P. Armstrong Brent Kennedy James T. Watson Patricia K. Morley-Forster Irvan Yee Ronald Butler 《Journal canadien d'anesthésie》2002,49(1):72-80
PURPOSE: The use of opioids in labour analgesia has primarily been as an adjuvant to local anesthetics. For early labour, satisfactory analgesia with epidural sufentanil alone is possible. This study evaluates the impact of epinephrine on sedative side effects and analgesia related to the latter technique. METHODS: After Institutional Review Board approval and informed consent this prospective, randomized, double-blind study evaluated 43 nulliparous subjects requesting epidural analgesia. The study site, a tertiary care obstetric unit, accommodates 3500-4500 deliveries annually. Group selection was randomized and blinded by selection of a sealed envelope containing a number which corresponded to a premixed labelled syringe of saline or epinephrine (100 microg/mL). An epidural catheter was placed in a standardized fashion. All subjects received 40 microg of sufentanil and 0.5 mL from the premixed syringe, diluted to 10 mL with NaCl. A blinded observer collected data on maternal sedation, lightheadedness, hemodynamics, oxygenation, and fetal heart rate over a one-hour period following sufentanil injection. RESULTS: The addition of epinephrine significantly (P <0.05) reduced the incidence of sedation and lightheadedness after epidural sufentanil at all data collection points, except two. Analgesic duration was also significantly prolonged by this addition (120 +/- 56 vs 84 +/- 32 min). Maternal satisfaction was high regardless of solution. CONCLUSION: Forty micrograms of epidural sufentanil produces satisfactory analgesia in early labour. The addition of epinephrine improves the side effect profile of this technique while prolonging the duration of analgesia. Epidural sufentanil requires attention to maternal monitoring of oxygenation as maternal desaturation occurred in both groups. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
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Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2