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111.

This study focuses on one often overlooked political communication-based media effect, intramedia mediation, and the indirect effects that stem from relationships that exist among various forms of media use. Data from a 2000 national Annenberg election panel survey are used to assess a series of relationships between television and newspaper public affairs use and how these forms of media consumption affect citizens' knowledge of presidential campaign endorsements. The indirect effects that stem from the relationships that exist among these two forms of media use reflect the cumulative and complementary functions of mass communication consumption across time. An analysis of intramedia mediation in coordination with the study of the direct effects of public affairs media use on this study's outcome variable produces substantially larger overall effects for both forms of news use. Thus, the study of intramedia mediation contributes to a better understanding of the full range of media influences on a given outcome variable over the course of a political campaign. Ramifications of these findings are outlined and future lines of research summarized.  相似文献   
112.
A 27‐year‐old man was found dead in an advanced decomposition stage at home. On external examination, his body showed petechial hemorrhages of the skin. At autopsy, petechial hemorrhages of the epicardium were found, but no sign of meningitis was detected. Toxicological investigations remained negative. Bacteriological conventional analyses showed no significant result. Neisseria meningitidis serogroup B was finally isolated on cerebrospinal fluid by a specific real‐time polymerase chain reaction. To our knowledge, there are no available data about the postmortem diagnosis of an infectious cause of death in a decomposed corpse. In such situations, the polymicrobial overgrowth usually hampers the interpretation of bacteriological conventional methods and questions their diagnostic value. Such molecular bacteriological approaches appear to constitute an important diagnostic tool for forensic scientists and should be widely processed in case of suspected infectious death or sudden death whatever the postmortem interval.  相似文献   
113.
Abstract: The American Academy of Pediatrics’ Committee on Child Abuse and Neglect, Section on Ophthalmology, acknowledges that searching for retinal hemorrhages (RHs) in infants only in cases of suspected of abuse creates selection bias. However, they also recommend that postmortem eye removal might not be indicated “in children who have clearly died from witnessed severe accidental head trauma or otherwise readily diagnosed systemic medical conditions.” Although infrequently described in the child abuse literature, peripapillary intrascleral hemorrhages (bleeding in the sclera at the optic nerve insertion)—putatively from severe repetitive acceleration/deceleration forces with or without blunt head trauma—have been considered essentially pathognomonic for abusive head trauma (shaken baby syndrome). We present two neonates who sustained accidental, severe in utero head injuries and had associated extensive RHs and optic nerve sheath hemorrhages with peripapillary intrascleral hemorrhages detected at autopsy. Neither neonate had a documented clinical fundal examination in the intensive care unit.  相似文献   
114.
International diplomacy, to the extent it is effective, should not only prevent escalation of low‐intensity conflict, but should also facilitate de‐escalation. This article focuses on the short‐term effects of managing low‐intensity civil wars through third‐party mediation. Specifically, we compare the efficacy of third party‐mediated direct (face‐to‐face) and indirect talks in low‐intensity civil wars from 1993 to 2004 using the Managing Intrastate Low‐Intensity Conflict data set. We argue that a focus on short‐term success is valid because of the relationship among mediation, short‐term success, humanitarian aid access, and peacebuilding. We also assess the roles of mediator identity, mediation strategy (behavior focus versus incompatibility focus), peace agreements, war type, per capita gross domestic product, level of democracy, and conflict duration. Our overarching finding is that direct forms of mediation in which all parties meet face to face were the most likely to yield short‐term success in the sample of civil wars that we analyzed.  相似文献   
115.
Abstract: Recommendations for the evaluation of an unexplained death in infancy include a postmortem skeletal survey (PMSS) to exclude skeletal trauma. Objectives of this study were to assess adherence to these recommendations in forensic autopsies in children equal to or less than 36 months of age, and what factors influence the use or nonuse of the PMSS. We surveyed pathologists who were members of the American Academy of Forensic Sciences. The survey included practice characteristics about where, when, and how PMSS were done. Nearly all respondents (99.6%) indicated they performed PMSS at least some of the time; however, almost a third did not use PMSS for all suspected Sudden Infant Death Syndrome (SIDS), abuse, unsafe sleep, or undetermined causes of death. Despite evidence that “babygrams” are inappropriate in a SIDS workup, 30% of pathologists use them preferentially. Despite SIDS being a diagnosis of exclusion that requires a PMSS, almost 10% of pathologists do not order a PMSS. Future research is necessary to reduce barriers to this important component of the pediatric forensic autopsy.  相似文献   
116.
死亡大鼠看家基因mRNA时序性降解的组织差异性研究   总被引:3,自引:2,他引:1  
目的研究死亡大鼠看家基因mRNA时序性降解的组织差异性,评价其用于死亡时间推断的价值。方法SD大鼠20只分为死后0、1、3、5、7d共5组,脊椎脱臼法处死大鼠,提取大鼠心、肝、脾、肺、肾、脑组织,在相应时间段提取RNA,应用一步法RT-PCR技术检测各组织中看家基因GAPDHmRNA和β-actinmRNA的水平,Vilber凝胶图像分析系统测定扩增产物IOD值,SPSS10.0统计软件对数据进行方差分析。结果GAPDHmRNA、β—actinmRNA扩增产物相对灰度与积分光密度值随死后经过时间的延长而逐渐减小,且与死亡时间显著相关,大鼠脾脏和脑组织GAPDHmRNA和β-actinmRNA在死后5d内可检出,心脏和肾脏在死后3d内可检出,而肝脏和肺脏GAPDHmRNA和β-actin mRNA降解较快,仅在死后1d内可检出。结论脑组织和脾脏中mRNA稳定性较好,适用于PMI特别是晚期PMI的推断。除环境温度外,环境湿度也是死亡时间推断中的重要影响因素。  相似文献   
117.
目的探讨大鼠皮肤切创后E-选择素表达规律及法医学意义。方法健康SD大鼠90只,随机分成4组:正常对照组、活体切创组(30min~7d12个时间点)、死后切创组(30min~3h3个时间点)、死后稳定性组(-20%6h-7d9个时间点,25%6h~3d5个时间点)。在大鼠头部建立皮肤切创模型,按设定的时间点取皮肤检材,运用免疫组化和图像分析技术,检测血管内皮E-选择素的表达规律。结果在活体切创组中,伤后1hE-选择素在血管内皮细胞内即呈阳性表达,持续至伤后7d,且随时间变化呈规律性表达。在正常对照及死后切创组未见阳性表达。死后-20%稳定性组各时间点E-选择素表达与死后即刻比较无显著性差异(P〉0.05)。25%各时间点与死后即刻比较有显著性差异(P〈0.01)。结论E-选择素在创伤后血管内皮细胞内特异性的表达具有时序性规律,且低温条件下稳定性较好。  相似文献   
118.
宏观调控是一个动态的过程,既有决策行为,也有执行行为;宏观调控作为国家经济调节的一种基本方式,是国家为克服市场缺陷中的盲目性、被动性和滞后性,实现社会经济的协调、稳定和发展而通过制定和实施社会经济计划、经济政策和具体经济调节手段来影响社会经济的"宏观结构和运行",从而引导和促进其按照国家所希望的方向和途径运行的一种国家经济职能活动.宏观调控对执行主体具有强制性,对被调控主体则不具有强制性.  相似文献   
119.
玻璃体液化学成分规律性改变与死亡时间推断的研究进展   总被引:1,自引:0,他引:1  
死亡时间(postmortem interval.PMI)的准确推断是法医尸体检验工作中的难题之一,PMI推断对刑事案件的侦察和审判具有重要的意义。人死亡后不同时间眼玻璃体液化学成分的规律性变化,如钾、镁、氨、尿素氮、肌酐和尿酸、次黄嘌呤、乳酸的含量逐渐升高,而钙、钠、酶类、葡萄糖、维生素C的含量逐渐降低,有助于比较准确地进行PMI推断。本文对其在法医学领域的研究进展进行综述。  相似文献   
120.
实时RT-PCR检测大鼠死后管家基因mRNA的时序性降解   总被引:1,自引:0,他引:1  
目的研究实时荧光定量RT—PCR方法检测死亡大鼠管家基因mRNA时序性降解的可行性,为死亡时间(Dostmortem interval,PMI)推断寻找新的研究手段。方法应用SYBR Green Ⅰ实时荧光定量RT—PCR技术.检测死后不同时间大鼠脑和脾中管家基因GAPDHmRNA及β—actinmRNA的水平,结果用循环阈值(简称Ct值)表示,分析死后经过时间与Ct值的线性关系,并建立死亡时间推断回归方程。结果GAPDH mRNA和β—actinmRNA的Ct值均与PMI之间存在显著的相关性。结论SYBR GreenⅠ实时荧光定量RT—PCR在定量分析mRNA降解的研究中是一个较理想的技术手段。选用管家基因作为PMI推断的研究对象,可在法医检案中消除其他基因因为个体差异带来的误差,更具实用性。Ct值作为动态监测机体死后不同时间点的客观指标.与死后不同时间点的线性关系良好,推断死后经过时间尤其是晚期死亡时间较为理想。  相似文献   
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