不同物理措施对烟粉虱和番茄TY病毒病的兼控研究

研究了防虫网、玉米屏障、温度等物理措施对烟粉虱和番茄TY病毒病的兼控效果。结果表明100目的防虫网效果最好,大棚内番茄黄化曲叶病毒病病株率为3.1%,防控效果达94.9%。在设置60目防虫网的前提下,在距棚1米处种植玉米能够有效的防止烟粉虱的入侵,防控效果为81.5%。当温度在20~30℃之间时番茄TY病毒病的发病率较高,当温度在30℃以上尤其是超过35℃时,已经发病的番茄植株会出现暂时的隐症现象。因此,同时采取多种物理措施并进行短时高温温棚能够有效的控制烟粉虱和番茄TY病毒病的危害。     

Infection frequency of Epstein-Barr virus in subgingival samples from patients with different periodontal status and its correlation with clinical parameters

Objective： To detect the infection frequencies of different genotypes of Epstein-Barr virus （EBV） in subgingival samples from chronic periodontitis （CP） patients, and to discuss the correlation between infection with EBV and clinical parameters. Methods： Nested-PCR assay was used to detect EBV-1 and EBV-2 in subgingival samples from 65 CP patients, 65 gingivitis patients and 24 periodontally healthy individuals. The amplicons were further identified by restriction fragment length polymorphism analysis （RFLP） with endonucleases Afa I and Stu I. Clinical parameters mainly included bleeding on probing （BOP）, probing depth （PD）, attachment loss （AL） in six sites of the dentition. Results： In CP patients, gingivitis and periodontally healthy individuals, the infection frequencies were 47.7%, 24.6% and 16.7% for EBV-1, and 15.4%, 7.7% and 0% for EBV-2, respectively. In 2 out of the 65 CP patients co-infection of EBV-1 and EBV-2 was found. The positive rate of EBV-1 in chronic periodontitis patients was higher than that in gingivitis patients （P=-0.01） and periodontally healthy individuals （P=-0.01）. But no significant difference was shown in EBV-1 frequency between gingivitis patients and healthy individuals （P〉0.05） or in EBV-2 frequency among the three groups （P〉0.05）. In CP patients, higher mean BOP value was found in EBV-1 or EBV-2 positive patients than that in EBV negative ones （P〈0.01）, but with no statistical difference in the mean PD or AL value between EBV positive and negative patients （P〉0.05）. After initial periodontal treatment, 12 out of the 21 EBV-1 positive CP patients did not show detectable EBV-1 in subgingival samples. Conclusion： nPCR plus RFLP analysis is a sensitive, specific and stable method to detect EBV-1 and EBV-2 in subgingival samples. Subgingival infection with EBV-1 is closely associated with chronic periodontitis. Infection of EBV in subgingival samples was correlated with BOP.     

浅谈校园网网络安全及应对措施

介绍了目前校园网的结构特点及网络安全状况,分析了网络安全存在的隐患及主要威胁,最后从实际情况出发,以＂全面防治,重点监控＂为原则,提出了加强校园网安全管理的几点应对措施。     

计算机病毒中的密码算法应用及防御方法综述

为躲避杀毒软件等安全产品的检测,密码算法通常被用于病毒攻击过程中。从病毒加壳技术、通信加密技术和加密勒索技术3方面对密码算法在计算机病毒的应用方法进行分析,结合典型案例分析病毒常用的加密算法和攻击流程,并从病毒样本脱壳、加密流量识别和数据加密恢复等方面提出相应的病毒防御对策。最后,针对病毒攻击技术的发展趋势,提出下一步研究方向和需重点解决的技术问题。     

一步之遥，八年光阴：丙肝病原体的发现到证明之路

2020年的诺贝尔生理学或医学奖授予了在发现丙肝病毒(HCV)方面作出突出贡献的哈维·阿尔特(Harvey J. Alter)、迈克尔·霍顿(Michael Houghton)和查尔斯·赖斯(Charles M. Rice)。然而,从1989年霍顿捕获HCV到1997年赖斯证明HCV能引发肝炎,间隔了8年时间。这看似一步之遥的距离何以耗时如此之久?文章通过回顾文献,对这一时期的研究脉络进行了梳理,明确了包括赖斯团队在内的不同研究者对于推进HCV相关认识所作的具体贡献。同时,针对研究过程中的两个关键节点——病毒RNA基因组3′末端的准确测序和感染性分子克隆的建立,文章从技术储备、路径依赖和目标定位的角度分析了赖斯团队为何能在科学研究竞争中拔得头筹。     

慢性乙型肝炎病毒感染学生体育锻炼的现状

运用问卷调查法对高校慢性乙肝感染学生的体育锻炼意识、目的、行为和技能进行了调查分析,结果表明,慢性乙肝病毒感染学生担心体育锻炼损伤身体,体育锻炼意识及达标率明显低于正常学生,体育锻炼目的主要是应付考试。有必要对这些学生加强卫生宣传教育,改革教学方法。     

《文献管理集成系统》的管理与维护

《文献管理集成系统》因其具有良好的通用性和开放性而拥有众多的用户。在使用该系统的过程中，必须在软硬件的升级和操作员的培训、数据库的管理和操作、网络病毒的防范等方面进行科学、规范的管理和维护。对该系统因操作不当而在采编、流通、检索、借阅等环节所造成的故障，应及时找出原因并加以排除。文章是笔者对几年来使用该系统的一次比较全面的经验总结。     

计算机病毒及防范

随着计算机技术及计算机网络的发展 ,伴随而来的计算机病毒传播问题越来越引起人们的关注。目前计算机病毒可以渗透到信息社会的各个领域 ,给计算机系统带来了巨大的破坏和潜在的威胁。因此 ,研究计算机病毒的防范措施已迫在眉睫。本文从计算机病毒的特点入手 ,来初步探讨对付计算机病毒的方法和措施。     

从计算机病毒的入侵特点探究反病毒技术

随着计算机病毒和反病毒技术的快速发展,人们越来越重视计算机安全.本文对计算机病毒的概念、入侵方式作了详细解释,介绍了当今流行的计算机病毒,如宏病毒、蠕虫病毒和木马病毒等,并结合反病毒技术的相关知识进行了归纳总结.     

Association between serum vitamin D and severity of liver fibrosis in chronic hepatitis C patients: a systematic meta-analysis

To conduct a systematic review of group studies assessing the association of serum vitamin D status with the severity of liver fibrosis in chronic hepatitis C patients using meta-analysis. The relevant research literatures were identified by searching PubMed and EMBASE databases prior to October 2013 with no restrictions. We included group studies that reported odds ratio (OR) estimates with 95% confidence intervals (CIs) or a mean with standard deviation (SD) for the association between serum vitamin D status and the severity of liver fibrosis in chronic hepatitis C patients. Approximately 8321 participants from several countries were included in this analysis. Six studies on serum vitamin D status and the severity of liver fibrosis were included in this meta-analysis. ORs with 95% CIs were extracted from four studies and the pooled ORs were 0.866 (95% CI, 0.649 to 1.157). The means with SDs were extracted from three studies and the pooled means were −0.487 (95% CI, −0.659 to −0.315). There was statistically significant heterogeneity among the mean data extracted studies (P=0.029; I ²=71.8%) but not among the OR data extracted studies (P=0.061; I ²=55.6%). Finally, results from the mean data extracted studies suggest that lower serum vitamin D is a risk factor for the severity of liver fibrosis in chronic hepatitis C patients. However, there is no conclusive evidence on this association because of inconsistencies between the OR data extracted studies and the mean data extracted studies.