FSH对仔猪睾丸支持细胞增殖和GDNF表达的调节

以原代培养的仔猪睾丸支持细胞(SC)为试验模型,研究了FSH对SC胶质细胞源性神经营养因子(GDNF)表达及其增殖的影响。结果显示,外源性添加FSH可促进GDNF蛋白表达,而且这种促进作用具有浓度和时间依赖关系,GDNF蛋白水平随着FSH浓度的增加而升高,当FSH浓度为50 ng/mL时,GDNF水平达到最高,然后逐渐降低;FSH(50 ng/mL)作用30 min,可显著促进GDNF蛋白的表达(P<0.05),当FSH作用1 h时,GDNF蛋白水平达到最高,随后逐渐降低。FSH可以时间-剂量依赖性促进SC增殖细胞核抗原(PCNA)的表达,FSH(50 ng/mL)作用30 min时,PCNA的表达显著增加(P<0.05),作用1 h达极显著水平(P<0.01),至2 h时,PCNA蛋白的表达水平达到最高,随后逐渐降低。提示,FSH可在体外条件下通过刺激SC表达GDNF进而促进其增殖。     

DOES CRIME JUST MOVE AROUND THE CORNER? A CONTROLLED STUDY OF SPATIAL DISPLACEMENT AND DIFFUSION OF CRIME CONTROL BENEFITS*

Recent studies point to the potential theoretical and practical benefits of focusing police resources on crime hot spots. However, many scholars have noted that such approaches risk displacing crime or disorder to other places where programs are not in place. Although much attention has been paid to the idea of displacement, methodological problems associated with measuring it have often been overlooked. We try to fill these gaps in measurement and understanding of displacement and the related phenomenon of diffusion of crime control benefits. Our main focus is on immediate spatial displacement or diffusion of crime to areas near the targeted sites of an intervention. Do focused crime prevention efforts at places simply result in a movement of offenders to areas nearby targeted sites—“do they simply move crime around the corner”? Or, conversely, will a crime prevention effort focusing on specific places lead to improvement in areas nearby—what has come to be termed a diffusion of crime control benefits? Our data are drawn from a controlled study of displacement and diffusion in Jersey City, New Jersey. Two sites with substantial street‐level crime and disorder were targeted and carefully monitored during an experimental period. Two neighboring areas were selected as “catchment areas” from which to assess immediate spatial displacement or diffusion. Intensive police interventions were applied to each target site but not to the catchment areas. More than 6,000 20‐minute social observations were conducted in the target and catchment areas. They were supplemented by interviews and ethnographic field observations. Our findings indicate that, at least for crime markets involving drugs and prostitution, crime does not simply move around the corner. Indeed, this study supports the position that the most likely outcome of such focused crime prevention efforts is a diffusion of crime control benefits to nearby areas.     

浅谈公安新闻写作与受众心理

公安新闻写作必须重视和研究受众心理。受众的求新求异心理、求知得益心理、逆反心理、休闲娱乐心理等对公安新闻作品都提出了新的要求。只有重视受众心理 ,才能产生好的公安新闻作品     

欧盟安全模式的体系层次分析

欧盟安全模式在冷战后日益突出,其特点在于通过有效的多边主义来维护安全。在冷战期间西欧国家地处两极对抗的前沿,两极格局的终结也对欧盟国家造成了重大冲击。因此,欧洲安全模式的形成和发展深受体系结构和体系进程的影响和制约。其中,结构因素发挥更为重要的作用,但同时体现为国际制度的进程因素对于巩固和维护欧洲安全也有重大的反作用。国际制度无法独立于体系结构影响国家行为,在欧洲安全模式形成的过程中,体系结构是独立的自变量,国际制度则是干预变量。     

建立交通管理社区警务体制刍议

随着社会经济的发展 ,原有的交通勤务管理方式的局限性越来越突出 ,改革现有的交通勤务管理模式 ,建立社区警务体制 ,是适应城市社区改革 ,推进交通安全社会化 ,提高管理效能 ,发挥民警主观能动性的需要。对此 ,应合理设置警务管理区 ,确定交通管理社区警务职责 ,规范交通管理社区警务运作模式。     

如何有效地开展安全检查

安全检查是安全保卫工作中及时发现、消除安全隐患的一项重要措施 ,但是在实际工作中却存在检查内容不完善 ,操作性不强 ,流于形式的现象。根本上解决这一问题必须在安全检查的内容上、形式上及其检查时机等方面进行更加合理的界定和把握 ;并利用现代先进科学技术拓宽安全检查的范围 ,提高安全检查的准确性。     

论"劳模精神"的内涵和弘扬

"劳模精神"是中国工人阶级在我国社会主义建设各个历史时期不断凝聚传承的宝贵精神财富."劳模精神"与时俱进,不断丰富发展,是激励工人阶级投身社会主义现代化建设的强大精神动力.要以劳动模范为榜样,调动广大职工的劳动热情,充分发挥工人阶级在构建和谐社会中的主力军作用.     

论刑事法律全球化时代的"国民不引渡"原则

在刑事法律全球化日趋成为一种发展趋势的今天,如何有效地进行国际刑事司法合作,消除合作中的羁绊,已经成为国际刑法需要认真探讨和研究的重大课题.从保护本国国民的利益出发,不将在外国犯罪的本国国民交给外国审判,或者不让本国国民在异国他乡的监狱中服刑,一直以来都是很多国家的做法.但是"国民不引渡"给国际刑事司法合作的顺利进行带来了难以克服的障碍.因此,新形势下采取新的立法势在必行.     

Scale, technique and composition effects in the Mexican agricultural sector: the influence of NAFTA and the institutional environment

More than a decade after NAFTA (North American Free Trade Agreement) entered into force, the environmental effects of agricultural trade liberalization in Mexico are still controversial, emerging, and not fully understood. This paper contributes to the literature that aims to explore trends in input use in the agricultural sector in Mexico during the post-NAFTA period among both commercial/industrial and traditional/rainfed farmers, and examines the influence of the national and multilateral institutional framework on these outcomes. We decompose the post-NAFTA agricultural production data into scale, technique and composition effects to estimate the impact that trade liberalization has had on the use of fertilizer and land use, two key agricultural inputs for which reliable aggregate data is available. We conclude that among commercial farmers patterns of crop type specialization and significant technological improvements have led to some declines in fertilizer use but they have been offset by growth in fertilizer use associated with growing agricultural output. Among traditional farmers increased output and specialization in land-intensive grain crops are contributing to an increase in land under cultivation and technological improvements show the potential, but not yet not the strength, to counteract these effects. We analyse the environmental institutional framework and rural development plans, observing that institutional weaknesses have, in several instances, reduced the environmental benefit of technique and composition effects. We conclude with recommendations about how the Mexican agricultural sector might reap the environmental benefits of international agricultural trade.     

关于公司法实施中的若干问题

在公司法实施中暴露的主要问题是发起人虚假出资、控制股东行为不规范、公司人格混同及被滥用现象突出。完善公司立法应立足中国国情,统一公司与企业法,重构公司资本制度,降低公司设立门槛,完善公司治理,细化债权人保护规则以增强法的可诉性;在公司司法方面,宜完善司法解释并由最高人民法院公布公司案例,发挥其引导作用;在揭开公司面纱方面尤其应结合中国的国情和司法实践,而不宜机械地照般国外的理论。