首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   730篇
  免费   44篇
各国政治   6篇
工人农民   3篇
世界政治   14篇
外交国际关系   69篇
法律   346篇
中国共产党   25篇
中国政治   131篇
政治理论   32篇
综合类   148篇
  2023年   12篇
  2022年   4篇
  2021年   12篇
  2020年   30篇
  2019年   20篇
  2018年   21篇
  2017年   23篇
  2016年   26篇
  2015年   15篇
  2014年   40篇
  2013年   73篇
  2012年   38篇
  2011年   46篇
  2010年   33篇
  2009年   38篇
  2008年   58篇
  2007年   53篇
  2006年   44篇
  2005年   35篇
  2004年   35篇
  2003年   36篇
  2002年   23篇
  2001年   24篇
  2000年   23篇
  1999年   2篇
  1997年   2篇
  1996年   1篇
  1995年   1篇
  1992年   2篇
  1990年   1篇
  1988年   1篇
  1985年   1篇
  1984年   1篇
排序方式: 共有774条查询结果,搜索用时 15 毫秒
121.
羊口疮病毒环介导等温扩增快速检测方法的建立及应用   总被引:2,自引:0,他引:2  
参照GenBank中登录的羊口疮病毒(ORFV)序列(Gu320351),针对OrfV的B2L基因保守区域设计了4条引物,通过优化反应条件,建立了检测OrfV的环介导等温扩增技术(LAMP),并进行了特异性试验、敏感性试验及临床样本检测。结果显示,用建立的LAMP方法对OrfV阳性样品扩增产物的电泳呈特征性梯状条带,而绵羊痘病毒、蓝舌病病毒、口蹄疫病毒、丝状支原体山羊亚种、山羊痘病毒及健康山羊皮肤的扩增产物电泳后均无扩增条带。建立的LAMP方法对OrfV的最低检出量为5.3fg,比常规PCR方法高1 000倍。表明建立的LAMP方法特异性强,敏感性高。对6份临床样本的检测结果显示,OrfV阳性检出率为83.33%(5/6),与常规PCR的符合率为100%。本试验为羊口疮病例的临床诊断和OrfV的快速检测提供了新的方法。  相似文献   
122.
Increased use of water search dogs for detecting submerged bodies has created the need for a better understanding of scent emanating from the bodies and how it transits the water to the dog's nose. A review of recent literature identifies likely scent sources, potential scent transport processes, and research needs. Scent sources include gases in bubbles or dissolved in the water, liquids as buoyant plumes and droplets or dissolved in the water, and solids consisting of buoyant particulates with secretions, bacteria, and body fluids. Potential transport processes through the water include buoyancy, entrainment, and turbulence. Transport processes from the water surface into the air include volatilization and evaporation enhanced by bubble bursting, breaking waves, splashing, and wind spray. Implications for the use of water search dogs are examined. Observations of submerged, decomposing bodies are needed to quantify the physical and chemical characteristics of the scent and scent transport processes.  相似文献   
123.
Through a comparison of fingermark sweat corrosion of α phase brass in both the U.K. and Iraq, we show how samples from Iraq have improved fingermark corrosion over U.K. samples that require no additional enhancement prior to visualization. Over 50% of Iraqi samples produced fingermark corrosion with full ridge detail compared with 0% from the U.K. X-ray photoelectron spectroscopy analysis of the fingermark corrosion products showed that Iraqi samples exhibit more dezincification with the Zn:Cu ratio averaging 1:1.82 compared with 1:3.07 for U.K. samples. Auger spectroscopy showed the presence of both zinc oxide and copper (I) oxide. No copper (II) was observed on the surface of the corroded brass. Opportunities to exploit the optical properties of these thin film oxides to enhance the visualization of fingermark corrosion are considered, and the potential to use fingermark corrosion of metal as a means of visualizing fingerprints in war zones is discussed.  相似文献   
124.
论视频监控的犯罪预防功能及犯罪侦查价值   总被引:1,自引:0,他引:1  
各国的犯罪预防理论发展至今,已经形成了比较完善的犯罪预防体系,主要包括司法预防、社会预防和情景预防三种模式。在我国的犯罪预防体系中,向来重视司法预防和社会预防,而对情景预防关注不够,情景预防措施尚不完善。作为一种对犯罪的干预,视频监控是一种对情境犯罪的干预,研究发掘其在犯罪预防中的作用对完善犯罪预防体系具有重要意义。同时,视频监控系统在犯罪侦查方面也具有重要作用。  相似文献   
125.
目的 查找嵌合基因的来源并进行父母和孩子的亲权鉴定.方法 采用Chelex-100法抽提基因组DNA,用复合扩增和荧光检测技术对STR、X-STR和Y-STR基因座进行分型.结果 父亲为XX,XY基因嵌合体,其能够提供给孩子必须的遗传基因.结论 父亲为被检孩子的生物学父亲.  相似文献   
126.
视频侦查是指侦查机关根据案件的需要,通过视频监控资料的调取、观看、分析和应用四个环节,实现对犯罪的动态分析和综合判断,以发现和确定犯罪嫌疑人、寻找破案线索,为案件侦查提供方向的一种侦查措施。视频侦查已成为继刑事技术、行动技术、网侦技术之后侦查破案的技术支撑和新的破案增长点,成为强化社会治安控制的有效手段,对提高侦查机关打击犯罪的效能具有重大意义。  相似文献   
127.
Bond and Uysal (this issue) complain that expert lie detectors identified by O'Sullivan and Ekman (2004) are statistical flukes. They ignore one class of experts we have identified and misrepresent the procedures we use to identify the others. They also question the psychometric validity of the measures and protocol used. Many of their points are addressed in the chapter they criticize. The fruitfulness of the O'Sullivan-Ekman protocol is illustrated with respect to improved identification of expert lie detectors, as well as a replicated pattern of errors made by experts from different professional groups. The statistical arguments offered confuse the theoretical use of the binomial with the empirical use of the normal distribution. Data are provided that may clarify this distinction.  相似文献   
128.
The current study examined psychopathy and nonverbal indicators of deception in an incarcerated sample. Nonverbal behaviors were coded from videotapes of 45 male offenders telling true and fabricated stories about crimes. Interpersonal features of psychopathy were associated with inflated views of lying ability, verbosity, and increases in blinking, illustrator use, and speech hesitations. While lying, the more psychopathic offenders spoke faster and demonstrated increases in blinking and head movements. Indicators of deception in offenders were somewhat different from those typically observed in non-offender populations. These findings indicate that personality factors may have an impact on nonverbal indicators of deception in criminal justice settings where the detection of deception is of utmost concern.  相似文献   
129.
The detection of trace explosives is important for forensic, military, and homeland security applications. Detection of widely used nitroaromatic explosives (trinitrotoluene [TNT], 2,4-dinitrotoluene [DNT], picric acid [PA]) was carried out using photoluminescent metallole-containing polymers. The method of detection is through the quenching of fluorescence of thin films of the polymer, prepared by spray coating organic solutions of the polymer, by the explosive analyte. Visual quenching of luminescence (lambda(em) approximately 400-510 nm) in the presence of the explosive is seen immediately upon illumination with near-UV light (lambda(ex)=360 nm). Detection limits were observed to be as low as 5 ng for TNT, 20 ng for DNT, and 5 ng for PA. In addition, experiments with normal production line explosives and their components show that this technology is also able to detect composition B, Pyrodex, and nitromethane. This method offers a convenient and sensitive method of detection of trace nitroaromatic explosive residue.  相似文献   
130.
Abstract: This article extends the application of 1,2,4‐triazine‐based chromogenic reagents to the detection of nonferrous metal traces left on contact with canvas and human skin. The possibility of detection of iron traces resulting from contact with objects made of stainless steel was investigated as well. Additionally, the ability of triazines to form chromatic complexes with Zn2+, Ni2+, Co2+, Cu2+, Cr3+, and Al3+ ions was studied spectrophotometrically. Molar absorption coefficients, ranging from 8.8 to 29.9 × 103/M/cm, provide high sensitivity of 1,2,4‐triazines toward nonferrous ions, thus, enabling the detection at concentrations as low as a few μM. The method was sensitive enough to detect traces resulting from a 1‐min contact with a stainless steel made object, which is commonly considered as a corrosion‐resistant material. The amounts of metal ions transferred to the skin after a 2‐min contact with objects made of brass, zinc, and copper were sufficient to develop chromatic imprints.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号