一种具有直接免疫的时滞计算机病毒模型的Hopf分支

以计算机病毒的潜伏期时滞为参数,研究了一类具有直接免疫的时滞SIR计算机病毒动力学模型的Hopf分支。通过分析相应特征方程根的分布,得到计算机病毒模型的局部稳定性和产生局部Hopf分支的充分条件,并利用仿真实例对理论分析结果的正确性进行了验证。     

乙酰水杨酸(阿司匹林)体外对流感病毒H1N1的抑制作用

探讨乙酰水杨酸(Acetylsalicylic Acid)在体外对流感病毒H1N1的抑制作用。采用血球凝集试验、神经氨酸酶活性抑制试验和鸡胚接种法,观察AS对流感病毒H1N1的抑制作用。血球凝集试验可以看出,AS对流感病毒H1N1包膜表面的血凝素活性有一定的抑制作用,且作用较为显著;鸡胚培养法的结果显示,AS明显抑制了流感病毒H1N1在鸡胚内的增值,实验组血凝效价低于1:2,对照组血凝效价为1:512;神经氨酸酶活性抑制试验的结果显示,AS能够明显抑制流感病毒H1N1的神经氨酸酶活性。结果表明AS在体外对流感病毒H1N1有明显的抑制作用,其抑制机理可能与AS对流感病毒血凝素和神经氨酸酶活性抑制有关。     

Fine Motor Control is Related to Cognitive Control in Adolescents with Down Syndrome

The connection between human cognitive development and motor functioning has been systematically examined in many typical and atypical populations; however, only a few studies focus on people with Down syndrome (DS). Twelve adolescents with DS participated and their cognitive control, measured by the Corsi-Block tapping test (e.g., visual working memory), the Auditory Memory span test (e.g., verbal working memory) and the Tower of London test (e.g., cognitive planning), and motor control, measured by the Purdue Pegboard (e.g., fine motor control), were measured in this study. Results indicate that if people with DS have better performance in fine manual dexterity, they will have better performance in cognitive planning and verbal working memory abilities. The co-activation hypothesis of the prefrontal area and the cerebellum may support this positive relationship. Hence, it is suggested people with DS will obtain benefits in cognitive control by participating in further motor intervention.     

Combining fiber dissection,plastination, and tractography for neuroanatomical education: Revealing the cerebellar nuclei and their white matter connections

In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white matter increases, the needs for white matter anatomy education are changing. Because cross‐sectional images and formalin‐fixed brain specimens are often insufficient in visualizing the complexity of three‐dimensional (3D) white matter anatomy, obtaining a comprehensible conception of fiber tract morphology can be difficult. Fiber dissection is a technique that allows isolation of whole fiber pathways, revealing 3D structural and functional relationships of white matter in the human brain. In this study, we describe the use of fiber dissection in combination with plastination to obtain durable and easy to use 3D white matter specimens that do not require special care or conditions. The specimens can be used as a tool in teaching white matter anatomy and structural connectivity. We included four human brains and show a series of white matter specimens of both cerebrum and cerebellum focusing on the cerebellar nuclei and associated white matter tracts, as these are especially difficult to visualize in two‐dimensional specimens and demonstrate preservation of detailed human anatomy. Finally, we describe how the integration of white matter specimens with radiological information of new brain imaging techniques such as diffusion tensor imaging tractography can be used in teaching modern neuroanatomy with emphasis on structural connectivity. Anat Sci Educ. 7: 47–55. © 2013 American Association of Anatomists.     

点电荷在导体球壳内任意位置时电势的分布

详细讨论了点电荷在导体球壳内任意位置时,导体球壳所处空间电势、球壳内壁感应电荷的分布。     

液针刀治疗运动员第三腰椎横突综合征48例疗效观察

目的液针刀疗法治疗运动员第三腰椎横突综合征疗效观察。方法用液针刀疗法治疗本病48例,用传统疗法治疗本病30例,进行疗效观察对比。结果液针刀疗法治疗本病总有效率为100 %,传统疗法治疗本病总有效率为83.3%,有显著差异(P<0.01)。结论液针刀疗法和传统疗法对治疗运动员第三腰椎横突综合征均有疗效,但液针刀疗法显效率明显高于传统疗法,液针刀疗法治疗运动员第三腰椎横突综合征,效果好,无毒副作用,安全可靠,简便易行,患者易于接受。     

肥胖及相关问题的认识(综述)

有关肥胖机制的研究很多,提出了各种假说.对相关的肥胖危害问题也进行了研究,提出了不同的观点,就其相关知识进行总结.