罕用药政策对生物医药产业的影响——基于美国生物科技公司的案例研究

美国罕用药物法案本意是用来鼓励制药产业研发和生产不具有商业价值的罕见药物,但是这项政策却对美国生物制药产业起到了关键性的推动作用。本文首先介绍了美国罕用药物法案颁布的背景及其所提供的优惠政策并回顾了颁布以来所取得的成就,然后以美国最成功的四家生物科技公司的发展为案例分析了罕用药物法案对美国生物医药产业的影响,结果表明通过科技推动和经济拉动罕用药物政策不但鼓励了罕用药的研发和生产还成功地推动了美国生物医药产业发展。     

方向自悟暴露--探寻初中科学高效教学策略

在我们的教育教学工作过程中如何协调好教与学的双边关系,提高课堂教学的效率,这是我们永恒的主题。本文就学习目标如何表述和展示,如何用情景材料教学,帮助学生领悟,如何将学生的学习问题暴露再教学,作了一些探讨。     

运动减肥对肥胖儿童少年红细胞膜磷脂酰丝氨酸外翻及ATPase酶活性的影响

目的:探讨肥胖儿童少年红细胞膜PS外翻水平和ATP酶活性及运动减肥干预对其的影响.方法:对64名肥胖儿童少年(按体脂百分比分为轻、中和重度肥胖组共3组)进行4周有氧运动减肥,采用流式细胞术测定红细胞膜PS外翻,干预前后进行血脂、PS外翻及Na K+ - ATPase和Ca2+ Mg2+- ATPase酶活性的测定.结果:运动干预前轻度肥胖组PS外翻与其他2组肥胖者之间存在显著性差异(P≤0.05),HDL仅在轻度组和重度组之间存在显著性差异;运动干预后Na+ K+ -ATPase活性显著增加(P≤0.05),CE2+ Mg2+- ATPase活性虽有增加,但未呈显著性水平;运动干预后PS外翻虽然有所下降,但无显著性差异.结论:脂代谢紊乱的初期,膜PS外翻可能比血脂指标更能体现肥胖的发展.有氧运动减肥能显著增加红细胞膜Na+ K+ - ATPase活性,改善红细胞膜PS外翻水平,但后者对运动干预的效应滞后于血脂变化.     

模拟海拔4800m急性低氧运动对肌氧饱和度的影响

目的:观察急性低氧运动对肌氧饱和度的影响,探讨肌氧饱和度与脉搏血氧饱和度(Pulse Oxy-gen Saturation,SpO2)相关关系。方法:以42名健康男性大学生为实验对象,采用无损伤的近红外光谱技术(near infrared spectroscopy,NIRS)监测常氧、急性低氧暴露6 h期间肌氧饱和度,同时检测SpO2。结果:肌氧饱和度运动开始后显著下降,急性低氧运动下降幅度加大;肌氧饱和度和SpO2呈正相关(r=0.949,P<0.01)。结论:肌氧饱和度相对有效下降值(Deff)反应运动中组织动员和利用氧气情况,可评定人体运动过程中肌肉氧化代谢能力;低氧运动时肌氧饱和度随血氧饱和度的下降而降低;肌氧饱和度有望成为低氧训练适应能力的简单无创预测指标。     

连锁零售药店的GSP管理实施与研究

药品作为一种关系百姓生命安全的特殊商品,保证药品质量成为医药企业生存、发展的关键。除GSP认证外,连锁零售药店质量管理常规化成为确保销售药品质量的重要环节,本文旨在分析如何确保GSP认证后不出现质量管理滑坡,确保连锁零售药店质量管理常规化。     

不同药物对一次力竭游泳小鼠脑纹状体自由基代谢的影响

以人参为阳性对照,研究北冬虫夏草和辽东B木对一次力竭小鼠纹状体自由基代谢的影响及其机制。方法:雄性昆明种小鼠,随机分为5组:安静组,力竭运动组,虫草加力竭运动组,B木加力竭运动组,人参加力竭运动组,运动模式为一次无负重力竭游泳,之前6周给相应组大鼠服用北冬虫夏草发酵液、辽东B木提取物和人参茎叶提取物,最后一次运动后即刻取样测定各组小鼠纹状体MDA、T-AOC及游泳至力竭的时间。结果:一次力竭游泳后,运动组小鼠纹状体MDA含量显著增高(P<0.01),T-AOC显著下降(P<0.01);虫草组纹状体MDA含量明显低于运动组(P<0.05),T-AOC明显高于运动组(P<0.05);B木组小鼠纹状体MDA含量显著低于运动组(P<0.01),T-AOC明显高于运动组(P<0.05);人参组小鼠纹状体MDA含量显著低于运动组(P<0.01),T-AOC显著高于运动组(P<0.01);各服药组小鼠游泳至力竭的时间明显延长(P<0.05)。结论:小鼠在进行一次力竭运动后,纹状体内脂质过氧化水平升高,总抗氧化能力下降;服用北冬虫夏草、辽东B木及人参能够降低力竭游泳小鼠纹状体脂质过氧化水平,提高总抗氧化能力,并延缓中枢疲劳的发生。     

高原或低氧环境下脱水与补液的研究进展

高原或低氧环境下体液平衡的改变主要表现为脱水和尿钠排泄。这与低氧刺激下交感神经兴奋性提高,外周化学感受器激发肾脏反应及体液调节激素的改变有关。低氧刺激使机体对营养素和液体的要求提高,但摄入降低,因此,机体应当补充足够的营养素和富含碳水化合物及电解质的液体。综述了高原或低氧环境下机体的体液平衡改变及其机制,提出了低氧下补液的主要原则,并指出了亟待研究的主要问题。     

Brain natriuretic peptide and optimal management of heart failure

BRAIN NATRIURETIC PEPTIDE Several studies demonstrated that the heart is an endocrine organ (Henry and Pearce, 1956; Kisch, 1956; de Bold, 1985; de Bold et al., 1981; 1996; 2001). Atrial natriuretic peptide (ANP) was the first cardiac hormone identified in 1984 (Kangawa et al., 1984; de Bold et al., 1981). Later on, a new com- pound from pig brain was found, which had similar natriuretic and diuretic effects as ANP (Sudoh et al., 1988). This peptide was named brain (B-type) natr…     

Study on the neurotoxic effects of low-level lead exposure in rats

Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.