基于PI3K/AKT/mTOR信号通路探讨化瘀通络灸促血管性痴呆大鼠髓鞘再生的作用机制

目的 观察化瘀通络灸对血管性痴呆(vascular dementia, VD)大鼠胼胝体磷脂酰肌醇3激酶(phosphatidylinositol 3 kinase, PI3K)/蛋白激酶B(protein kinase B,AKT)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin, mTOR)信号通路的影响,探讨化瘀通络灸促VD大鼠髓鞘再生的作用机制。方法 经Morris水迷宫筛选后,随机选取12只大鼠纳入假手术组,剩余大鼠复制VD模型成功后,随机分为模型组、艾灸组、艾灸+LY294002组,每组12只。艾灸组予以化瘀通络灸干预,艾灸+LY294002组在化瘀通络灸干预的基础上予以PI3K抑制剂LY294002腹腔注射,采用Longa评分法评价各组大鼠神经功能损伤程度,Morris水迷宫实验检测各组大鼠学习记忆能力,Western blot法检测各组大鼠PI3K/AKT/mTOR信号通路相关蛋白的表达水平,神经髓鞘固蓝染色法观察各组大鼠胼胝体髓鞘的形态,透射电子显微镜观察各组大鼠髓鞘超微结构。结果 与假手术组比较,模型组和艾灸+LY294002组大...     

中国主要城市群的人口模式分类研究

城市群是区域经济和人口的主要空间载体,深入研究其人口集聚、发展状况,有利于促进城市群形成合理的区域发展格局。从构成城市群的主要人口要素出发,选取反映城市群人口特征的若干主要指标,运用聚类分析方法,对我国主要城市群人口特征进行空间分类研究,发现中国19个主要城市群按照其主要人口特征可明显分为五个人口类别,各类别之间存在显著差异:第一类城市群包括珠三角、长三角和京津冀3个城市群,特征是人口规模大、密度高、城市化水平高;第二类城市群包括成渝、长江中游、海峡西岸、山东半岛、北部湾、关中平原6个城市群,特征是人口增长率高、人口空间分布比较合理;第三类城市群包括中原、哈长、山西中部、滇中、辽中南5个城市群,特征是人口增长率低、城市化水平不高;第四类城市群包括兰西、黔中2个城市群,其特征是人口规模小、城市化水平低;第五类城市群包括天山北坡、呼包鄂榆、宁夏沿黄3个城市群,其特征是人口规模小、密度低、空间分布欠合理。在促进城市群发展的政策方面应进行差异化人口政策引导,在优化人口发展的侧重点和具体策略方面应有针对性区别施策。     

公安高等院校英汉双语教学探析

英汉双语教学是一种新的教学方式。公安院校应从英汉双语教学的定位、双语教学的模式、双语教学对教师的要求与培养、双语教材的选用与建设以及双语教学的手段与方法等方面进行改革,提高公安院校大学生的英语听、说、读、写能力。     

刑事照相课程的改革与实践

刑事照相实践教学改革旨在解决教学体系、教学内容、教学方式、教学方法等不适应新形势及系统性、规范性不强等问题。从建立动态、科学的实验教学内容,确定科学合理的实践教学模式,使用多种辅助教学手段等几个方面进行改革与实践,以达到培养高素质、知识型、创新型、实用型公安专业人才的目的。     

肠复康方对急性放射性肠炎大鼠小肠黏膜细胞凋亡基因的影响

目的 探讨肠复康方对急性放射性肠炎大鼠一般情况及小肠黏膜相关细胞凋亡基因的影响。方法 以X线直线加速器给予实验大鼠全腹照射,建立急性放射性肠炎大鼠模型。将实验大鼠随机分成正常对照组,模型对照组,肠复康方低、中、高剂量组。模型复制成功后,肠复康各剂量组给予10 mL/kg灌胃,低、中、高剂量组剂量换算后分别含生药15.75、31.50、63.00 g/kg,模型对照组、正常对照组同时予等量生理盐水,连续30 d灌胃。期间观察大鼠精神状态、摄食进水、排便情况及体质量变化,处死后取相应部位的小肠用免疫组化及Western blot方法检测黏膜上皮细胞中凋亡基因Caspase-3、Bax、Bcl-2的表达。结果 肠复康方干预大鼠的精神状态、饮食进水、排便情况较模型对照组改善;与模型对照组比较,肠复康方干预大鼠体质量显著增加,以中剂量组效优 (P<0.05）。肠复康方低、中、高剂量组小肠黏膜的凋亡基因Caspase-3、Bax和Bax/Bcl-2表达较模型对照组显著下调、Bcl-2显著上调 (P<0.05), 中剂量效优。结论 肠复康方具有改善急性放射性肠炎大鼠一般情况及抑制其细胞凋亡作用,以中剂量效优,其机制可能与下调小肠黏膜上皮凋亡基因Caspase-3、Bax表达及上调Bcl-2的表达,抑制细胞凋亡有关。     

通督调神针灸法对局灶性脑缺血再灌注模型大鼠皮质区CD34、CD133及血清VEGFR-2表达的影响

目的 探究通督调神针灸法对局灶性脑缺血再灌注模型（middle cerebral artery occlusion model/reperfusion model,MCAO/R）大鼠脑保护及血管新生的作用。方法 将150只SD大鼠随机分为假手术组、通督调神针灸组、常规针刺组、通心络药物组和模型对照组,每组30只。通督调神针灸组取百会穴艾灸,大椎穴刺络放血;常规针刺组选取风池、曲池、合谷、足三里、三阴交针刺治疗;通心络药物组予以通心络胶囊,每日每次1.0 g/kg灌胃。假手术组、模型对照组不予治疗;其余各组每日治疗1次,共28 d。治疗第7、14、21、28天处死大鼠立即取脑,脑组织石蜡包埋后切片,免疫组织化学法检测缺血皮质区CD34、CD133阳性表达,采用ELISA法检测VEGFR-2的表达。结果 MCAO/R大鼠缺血皮质区CD34、CD133及血清VEGFR-2表达量在第7天较高,随后逐渐降低;通督调神针灸法、常规针刺及通心络药物均可不同程度促进MCAO/R模型大鼠缺血皮质区CD34、CD133及血清VEGFR-2表达（P<0.05）,且通督调神针灸法促进MCAO/R模型大鼠缺血皮质区CD34、CD133及血清VEGFR-2表达水平高于常规针刺及通心络药物（P<0.05）。结论 通督调神针灸法能有效促进MCAO/R大鼠缺血皮质区CD34、CD133及血清VEGFR-2表达。     

细胞凋亡参与脑心综合征心肌损伤及针刺干预作用

目的 观察心肌细胞凋亡在脑心综合征(cerebral-cardiac syndrome,CCS)发病中的作用机制及针刺的干预作用。方法 从60只健康SD大鼠中随机选择10只作为伪手术组,其余50只用于CCS模型复制,从模型复制成功的大鼠中随机选取30只,分成模型组、针刺组和非经非穴组,每组10只。采用胶原酶加肝素联合注射大鼠尾状核方法复制CCS模型,伪手术组向大鼠尾状核注入等量生理盐水。模型复制后72 h处死动物,分别采用苏木精-伊红（hematoxylin-eosin,HE）染色、脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling,TUNEL)和免疫组织化学法检测心肌组织病理变化、细胞凋亡及半胱氨酸天冬氨酸蛋白酶3(Caspase 3)的表达。结果 HE染色示伪手术组心肌结构正常,模型组心肌细胞变性、坏死,大量平滑肌断裂;TUNEL及免疫组织化学染色提示模型组出现较多凋亡细胞,Caspase 3大量表达,针刺组TUNEL染色阳性细胞和Caspase 3阳性细胞均较模型组和非经非穴组显著减少(P<0.01)。结论 心肌细胞凋亡参与了CCS大鼠心肌损伤,其机制可能与上调凋亡蛋白酶Caspase 3表达有关,而针刺可拮抗CCS大鼠心肌组织细胞凋亡。     

Honeymoon or consolidation,or both?: Time dependence of democratic durability

Much research has been done to identify factors that facilitate or prevent democratic breakdown. Little attention, however, has been paid to the question of whether and how the baseline risk level (after controlling for the impacts of relevant factors) changes over time. Using a flexible parametric survival model, I analyse the duration of 149 democratic periods (1946–2008) and demonstrate that the baseline risk has an inverted-U shape, which provides evidence for the honeymoon effect and democratic consolidation. This finding has an important policy implication for democratic assistance programmes.     

Dyadic Effects,Relevance, and the Empirical Assessment of the Kantian Peace

Dyadic effects to a large extent account for the difficulty of explaining and predicting international conflict. In this study, I derive a statistical model to estimate unobserved dyadic effects in the dyadic analysis of conflict. The proposed model employs a hierarchical modeling approach to estimate dyadic effects, thereby avoiding the problems caused by the use of fixed effects models. Furthermore, it simultaneously addresses the important sample selection issue of identifying relevant dyads. I show that the estimation of dyadic effects significantly improves the model fit and generates several interesting findings. Substantively, this study makes an important contribution to the empirical evaluation of the Kantian peace. It argues that international organizations increase the likelihood of conflict of interest between member states but reduce the probability of militarized conflict. I demonstrate that the positive coefficient of international organizations in Oneal and Russett (1999) is biased in the positive direction. When the proposed statistical model is used, international organizations, together with trade and democracy, reduce the probability of conflict.     

Spatially and Sequentially Heterogeneous Discounts of Distressed Property Values in Cuyahoga County,Ohio

One of the most persistent public policy debates is over the aftermath of the foreclosure crisis and its continuing impact on housing markets. Distressed properties – including foreclosure and real estate-owned properties – tend to be sold at much lower prices than nearby comparable properties, often pulling down both surrounding property values and neighborhood morale. Recent findings show that these discounts for distressed properties are associated with various factors, but three important dimensions of these discounts remain relatively unexplored. First among these is the degree of variation in these discounts, even within the same regional market. Second is how discounts vary through the typical sequence of the distressed property transaction cycle. The final factor is the nature by which discounts vary according to the market participants – are the buyers/sellers individuals or institutions? This study examines these major factors affecting discounts, and estimates the spatially and sequentially heterogeneous discounts for distressed properties in the housing submarkets of Cuyahoga County, Ohio. Findings indicate that the discounts of distressed properties in the strong and weak submarkets substantially vary based on all three of these previously overlooked factors, yielding a more complex and nuanced housing context for practitioners and policymakers to consider.