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   4705篇
  免费   285篇
  国内免费   1篇
各国政治   355篇
工人农民   12篇
世界政治   640篇
外交国际关系   766篇
法律   1796篇
中国共产党   299篇
中国政治   558篇
政治理论   212篇
综合类   353篇
  2023年   28篇
  2022年   30篇
  2021年   19篇
  2020年   30篇
  2019年   40篇
  2018年   51篇
  2016年   32篇
  2015年   35篇
  2014年   161篇
  2013年   112篇
  2012年   298篇
  2011年   306篇
  2010年   189篇
  2009年   156篇
  2008年   214篇
  2007年   228篇
  2006年   241篇
  2005年   200篇
  2004年   190篇
  2003年   204篇
  2002年   199篇
  2001年   142篇
  2000年   137篇
  1999年   99篇
  1998年   78篇
  1997年   73篇
  1996年   69篇
  1995年   82篇
  1994年   79篇
  1993年   50篇
  1992年   54篇
  1991年   56篇
  1990年   52篇
  1989年   64篇
  1988年   101篇
  1987年   80篇
  1986年   82篇
  1985年   90篇
  1984年   87篇
  1983年   88篇
  1982年   59篇
  1981年   59篇
  1980年   80篇
  1979年   39篇
  1964年   21篇
  1962年   17篇
  1961年   14篇
  1959年   17篇
  1957年   15篇
  1956年   13篇
排序方式: 共有4991条查询结果,搜索用时 31 毫秒
821.
Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films.  相似文献   
822.
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.  相似文献   
823.
The external post-mortem examination, its deficient quality and possible causes have been the subject of numerous political and professional discussions. The external post-mortem examination is the basis for the decision whether further criminal investigations are required to clarify the cause of death. It is thus an essential instrument to ensure legal certainty. Before cremation, a second external post-mortem examination is performed by a public medical officer to make sure that errors of the first post-mortem are corrected. In the present study, cases were retrospectively analyzed in which a forensic autopsy had been ordered on the basis of the results of the post-mortem examination performed before cremation. The entries on the death certificate regarding the manner and cause of death were compared with the autopsy results. Between 1998 and 2007, 387 autopsies were ordered after external examination before cremation. In 55 cases (14.2%), the autopsy revealed a non-natural death, although a natural death had been attested on the death certificate. In descending order, a wrong manner of death was attested by clinicians, general practitioners and emergency physicians. With regard to the place where the first external post-mortem had been performed the lowest error rate was seen in nursing homes. Concerning the cause of death, discrepancies between the first post-mortem and autopsy were found in 59.4% of the cases. In this respect, general practitioners and clinicians were ranking first, whereas in nursing homes the cause of death was wrongly assessed in over 70% of cases. At present, the medical post-mortem does not meet the required quality standards, especially with regard to legal certainty. Determination of the cause of death on the basis of the external post-mortem examination is a challenging task even for the experienced medical examiner. As to the categorization of the manner of death it has to be stated that non-natural deaths are often not recognized or that the possibility to certify a death as unclear is not sufficiently used. As a result, it seems important to demand intensive, qualified, additional training in external post-mortem examinations for physicians.  相似文献   
824.
Re Edwards (2011) 4 ASTLR 392; [2011] NSWSC 478 adds to the small line of cases to have considered whether a woman can not only require medical staff to remove sperm from her dead male partner, but whether she is justified in terms of law and international human rights to use it to create children. In this case a Justice of the New South Wales Supreme Court framed the issue as "what right does a woman have to take sperm from the body of her deceased partner so that she may conceive a child?" He did so, despite the manifest ambiguity and difficulty in characterising the legislative rights in this case, without referring to substantive human rights obligations under international Conventions to which Australia is a ratifying party (particularly Art 10 of the United Nations International Covenant on Economic, Social and Cultural Rights and Art 23 of the United Nations International Covenant on Civil and Political Rights. Technological advances such as those creating the possibility of capturing a dead person's sperm by electro-ejaculation and creating children by subjecting it to intracytoplasmic sperm injection in connection with in vitro fertilisation have altered the balance of individual and social interests in deciding who should be regarded as owning a dead man's sperm and how that relates to basic common law rights of bodily inviolability without free consent. It is to be regretted that in jurisdictions lacking relevant constitutional human rights, or legislation requiring coherence with international human rights, judges do not avail themselves in cases of statutory ambiguity of interpretative insights to be gained from legally binding human rights treaties to which Australia is a party.  相似文献   
825.
Momcilovic v The Queen (2011) 85 ALJR 957; [2011] HCA 34 arose from a prosecution for drug trafficking brought under the Drugs, Poisons and Controlled Substances Act 1981 (Vic). The Australian High Court held that the Charter of Human Rights and Responsibilities Act 2006 (Vic) (the Charter) validly conferred a power on the Victorian Supreme Court and Court of Appeal to interpret legislation in a manner consistent with a defined list of human rights. By a slim majority it also held that the Charter validly created a judicial power to "declare" a law inconsistent with one or more enumerated human rights. In reaching its decision, however, the majority supported a narrow interpretation likely to undermine the intended capacity of the Charter to act as a remedial mechanism to reform laws, regulations and administrative practices which infringe human rights and freedoms. Although Momcilovic involved interpretation of a specific State human rights law, the High Court judgments allude to significant problems should the Federal Government seek to introduce a similar charter-based human rights system. Momcilovic, therefore, represents a risk to future efforts to develop nationally consistent Australian human rights jurisprudence. This has particular relevance to health and medically related areas such as the freedom from torture and degrading and inhuman treatment and, in future, enforceable constitutional health-related human rights such as that to emergency health care.  相似文献   
826.
俄罗斯现有的政治体制是"普京方案",专注于"内部改革",兼顾社会各种利益、问题和挑战,扮演着稳定局面的"保障者"和"危机管理人"的角色,但正在被社会大众所厌倦。因此,普京必须回归"战略管理者"的地位。然而,留给俄罗斯执政精英们用于决定转变的时间越来越少了。因此,当前亟须找到一种政治方略,确保"俄罗斯体系"不再经历新一轮的灾难和破坏性威胁。在此基础上建立社会和国家的"动态平衡"模式,这是俄罗斯历届领导人尚未完成的使命。只有实现国家现代化,重建社会、政治、经济和意识形态模式,使俄罗斯人获得政治民主地位,才是对于当代挑战的回答,其他任何方案都意味着历史悠久的俄罗斯将最终走向衰败和解体。  相似文献   
827.
中亚地区作为当前地缘政治博弈的中心之一,吸引了众多国家的目光,印度也不例外.其巨大的能源储备、战略性的地缘位置、有待开发的广阔商机都令印度在1998年后执行了明显倾向于积极的政策.尽管印度将中亚作为“扩展的邻国”,但印度和中亚并不直接接壤,于是,连接印度和中亚的阿富汗就成了印度“西北向”战略中的关键一环.美国发动阿富汗战争后,印度对阿富汗展现出积极姿态,不仅恢复了外交关系,而且还全面参与到阿富汗的重建工作中.随着美国撤出阿富汗的最后日期逐渐临近,阿富汗及中亚地区的前景也随之蒙上了一层阴影.确保阿富汗的稳定,反对恐怖主义、极端主义成为印度对阿富汗政策的优先战略目标.作为连接印度与中亚的通道,阿富汗的稳定与否直接关系到印度能否实现在中亚的战略利益.印度近年来在地区和全球的影响力逐步提升,希望能够在中亚地区的“新大博弈”中占有一席之地,以确保本国的国内安全、能源安全并拓展在本地区的经济合作空间.分析和理解哪些因素以及在何种程度上促使印度对作为连接印度和中亚的通道的阿富汗采取积极主动的政策,以及印度在中亚地区有哪些经济和地缘政治利益,是很重要的研究项目.  相似文献   
828.
In some circumstances, the presence of adipocere may retard decomposition and complicate postmortem interval estimation. This article explores the correlation between Accumulated Degree Days (ADD) and early stage formation of adipocere. Sixty wild rabbit (Oryctolagus cuniculus) carcasses were used in this experiment; a control group (N = 30) deposited directly on the ground surface and an experimental group (N = 30) completely submersed in water in individual buckets. Data (water and inner body temperature, pH, and total body score) were collected every 100 ADD. Results indicated that early stage adipocere is correlated to ADD and that its formation on submersed remains is more likely to occur after 630 ADD. Skin sloughing promoted the formation of adipocere. No adipocere was formed on any of the control group rabbits. This study also highlights the fact that multiple factors influence adipocere formation and it is suggested that further research needs to be conducted into this area.  相似文献   
829.
Although researchers have examined many aspects of fire modification, the rate and pattern of decomposition in charred remains have not been studied previously. This study utilized 48 domestic pigs, divided into 24 charred (head, neck, and limbs burned to Crow-Glassman level 1 and torso to level 2) and 24 un-charred pig carcasses. Decomposition of control carcasses was scored at 50 accumulated degree days (ADD) intervals, and charred carcasses were also observed and photographed at this time. A Charred Body Scale was subsequently created, and charred carcasses were scored retrospectively for the same ADD intervals. Analysis using a mixed-effect repeated measures model indicated that, while decomposition rate was not statistically different between the two groups (p = 0.2692), the charred remains initially displayed an ostensibly more advanced pattern. Body regions displaying significant charring decomposed at a faster rate (p < 0.001), while areas with very light levels of charring decomposed at a significantly slower rate (p < 0.001).  相似文献   
830.
Adolescence is a relatively short period between childhood and adulthood. It is very difficult to determine adulthood based on biological indicators. The third molar may be considered a potential age marker for the period between the ages of 16–21. Our study evaluated a set of 1700 panoramic radiographs of individuals aged between 5 and 21 years. Results confirmed the statistically significant difference in the course of third molars development. The mean deviation for individuals with one third molar agenesis is ?0.98 years, for individuals with two third molars agenesis ?1.89 years, and with three molars agenesis ?3.28 years. Thus, the extent of the deviation is directly proportional to the number of unformed third molars. The calculation of age according to the mean of stages of all third molars could lead to the underestimation of age. No intergender differences were found. Age determination using third molars could be used for forensic purposes.  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