流式细胞术及DNA倍体分析在胃肿瘤研究中的应用

目的了解胃癌的生物学行为.方法采用流式细胞术测定68例胃癌细胞DNA含量、S期及G2/M期细胞比率,并与胃癌生物学特性进行分析.结果二倍体癌浆膜受侵者S期细胞比率明显高于未受侵者(P<0.05),团块生长者G2/M期细胞比率明显高于弥漫状生长者(P<0.05)、淋巴结转移阴性和转移枚数少于5枚者(P<0.05),淋巴结转移至第2站,以远者G2/M期细胞比率明显高于淋巴结转移阴性和转移至第1站者(P<0.05).结论胃癌细胞DNA含量和细胞比率与胃癌生物学行为有一定关系.     

Degradation of 2,4-dichlorophenol catalyzed by the immobilized laccase with the carrier of FeaO4@MSS-NH2

With the Fe304@MSS （magnetic mesoporous silica spheres）-NH2 as the carrier and the glutaraldehyde as crosslinking agent, the immobilized laccase has been pre- pared and characterized by XRD, IR, SEM and BET etc. Under the optimal conditions, the removal efficiency of 2,4-DCP reached 88 % and the removal efficiency still remained 61.5 % after five cycles of operations. In virtue of GC-MS analysis, 2,5-dimethoxyl-l,4-quinone, 2-chlo- rine-l,4-dimethoxyl benzene, 3,3＇-dichlorine-4,4＇-dimeth- oxyl biphenyl, maleic acid phenol ester, and three kinds of maleic acid, alcohol ester, and para-hydroxyl phenol ester compounds have been identified as intermediate and final degradation products of 2,4-DCP, respectively. Besides, the degradation products of 2,4-DCP have been confirmed by performing the 1H-NMR and 13C-NMR experiments, further demonstrating the degradation mechanism of 2,4- DCP by the immobilized laccase.     

Association of cystatin C level and cardiovascular prognosis for patients with preexisting coronary heart disease： a meta-analysis

The association of circulating levels of cystatin C （CysC） and risk of recurrent cardiovascular events in patients with preexisting coronary heart disease are uncertain. To qualitatively and quantitatively address this issue, we performed a random meta-analysis of results from prospective studies on the topic. We searched elec- tronic and printed sources （up to 16 October 2011） using keywords and retrieved articles for seven prospective studies according to the selection criteria. Data were abstracted and meta-analysis was performed using the random-effects model （RevMan 5.0.23 software）. The cohorts involved 4,576 patients with preexisting coronary heart disease （CHD） and normal or mild chronic kidney disease, and follow-up ranged from 5.6 to 40.6 months. Highest versus lowest baseline CysC level was signifi- cantly associated with increased risk of cardiovascular events （OR 2.30, 95 % CI 1.80-2.94）, all-cause mortality （OR 5.69, 95 % CI 3.70-8.74）, but not with recurrent MI （OR 1.75, 95 % CI 0.77-4.00）. In heterogeneity testing for studies reporting cardiovascular events and all-cause mor- tality, no significant heterogeneity was found, and exclu- sion of any single study did not alter the overall finding. For risk of recurrent MI, significant heterogeneity was found among the five trials （Z2= 13.16, P=0.01, 12 = 70 %） and exclusion of the Taglieri et al. [12] study from the analysis resulted in a rise in relative risk （OR 2.36, 95 % CI 1.09-5.15）. In conclusion, for patients with established CHD, high baseline level of CysC is associated with increased risk of cardiovascular events and all-cause death during long-term follow-up.     

MiR-205 inhibits the invasion and migration of esophageal squamous cell carcinoma by modulating SMAD1 expression

Esophageal squamous cell carcinoma （ESCC） is one of the most lethal cancers worldwide. In this study, we aimed to investigate the underlying mechanisms of metastasis inhibition by miR-205 in ESCC. In microRNA （miRNA） array and quantitative RT-PCR analyses, we found that the expression level of miR-205 was significantly lower in patients with lymph node metastasis compared with that in patients without lymph node metastasis. After transfection of miR-205 mimics or inhibitors into ESCC cell lines, a significant negative correlation was observed between the expression level of miR-205 and Smad 1. In luciferase reporter assays, we revealed that miR- 205 inhibited the expression of SMAD1 by targeting the 3＇ untranslated region （3＇-UTR） of SMAD1 mRNA in ESCC cells. Furthermore, our results showed that miR-205 sup- pressed the invasion and migration of ESCC cells, whereas Smadl increased their invasion and migration. Taken together, our study demonstrates that miR-205 functions as a suppressor of tumor metastasis by regulating SMAD1 expression through targeting the 3＇-UTR of SMAD1 mRNAin ESCC. Therefore, miR-205 may be a potential therapeutic target for miRNA-based therapy of ESCC.     

青藏高原少数民族传统体育课程资源分析研究

文章通过实地走访、问卷调查等研究方法对青藏高原学校开发高原少数民族传统体育课程资源现状及优势进行了分析研究.结果表明,长期以来,青藏高原学校体育教学内容受竞技运动体系的影响,有着独特优势的高原少数民族传统体育课程资源并未在学校得到充分挖掘、开发和利用,这不仅导致大量高原少数民族传统体育课程资源的闲置,而且在很大程度上还制约着学校体育教学发展的进程以及高原少数民族传统体育文化的传承与发展.文章同时针对性地对青藏高原少数民族传统体育引入学校体育提出了若干对策建议.     

横向距离平方和最小法的合理性

作者首先通过作图发现样本点到直线的距离与其横向距离同增减,直观地证明了横向距离平方和最小法的合理性.然后证明了横向距离平方和最小法的估计量具有相合性、无偏性、有效性.并发现横向距离平方和最小法的估计量是一致最小方差无偏估计.     

某桁架式桥梁检测车垂直臂刚架结构的拓扑及尺寸优化

以某桁架式桥梁检测车垂直臂为研究对象,利用ANSYS参数化设计语言建立了该垂直臂的三维实体参数化有限元模型,选择了三种典型工况对垂直臂进行了有限元静力结构分析。采用面面接触单元来模拟垂直臂与连接架滑块之间的滑动副,准确计算了垂直臂与滑块间的受力和变形情况。分析了垂直臂主管臂厚、弦杆臂厚以及拓扑结构参数弦杆分布密度对其强度、刚度的影响,为提高垂直臂构件的力学性能提供了理论依据。基于分析结果,选出了垂直臂的最佳几何构型并应用于实际产品。     

重视课堂设计,彰显有机课堂

遵循学生的认知规律,使学生获得真正、灵活、深层的知识,通过知识的学习提高学生的能力素质,使学生能够举一反三灵活运用,从而提高语文课堂成效。在新课程时代背景下,以认知理论为指导的语文课堂设计,不仅要考虑学科本身的特点,更要遵循学生的认知发展规律。从学生的需要出发,确定正确的教学"路标",选择合理的教学"路径"。从而呈现最佳的教学"风貌"。在设计教学这个开放动态的过程中,课堂设计应多角度创设情境,强化学生对重点知识的熟练掌握,在理解的基础上,灵活迁移并达到学以致用的目的。深化学生对知识的理解,切实提高学生的能力。     

非Lipschitz的倒向随机微分方程解的稳定性

考虑一族含参数的倒向随机微分方程,在系数满足在一类非Lipschitz条件下证明了解的稳定性。     

浅析变电站工作中的危险点

电力企业作为我国支柱产业，成为促进国民经济发展的核心动力，电力系统的供电量不断满足人们的用电量需求。然而在整个系统供电运行的过程中，危险点无处不在，危险点既可能由于人为原因，也有可能由于设备原因。本文主要针对变电站工作中的危险点展开系列分析，涉及如何在具体的工作中辨别、分析危险点和如何针对危险点进行相关预防工作。只有意识到危险点的存在，针对危险产生的原因，才能行之有效地进行预防，减少电力工作的危险性，保证供电工作安全高效地完成。