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   5385篇
  免费   1056篇
世界政治   2篇
外交国际关系   1篇
法律   6368篇
中国政治   25篇
政治理论   8篇
综合类   37篇
  2024年   22篇
  2023年   81篇
  2022年   51篇
  2021年   86篇
  2020年   279篇
  2019年   276篇
  2018年   291篇
  2017年   404篇
  2016年   517篇
  2015年   369篇
  2014年   483篇
  2013年   495篇
  2012年   426篇
  2011年   573篇
  2010年   458篇
  2009年   457篇
  2008年   362篇
  2007年   327篇
  2006年   293篇
  2005年   54篇
  2004年   31篇
  2003年   34篇
  2002年   26篇
  2001年   16篇
  2000年   7篇
  1999年   1篇
  1998年   4篇
  1997年   11篇
  1996年   1篇
  1995年   3篇
  1994年   1篇
  1990年   1篇
  1988年   1篇
排序方式: 共有6441条查询结果,搜索用时 15 毫秒
91.
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain.  相似文献   
92.
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls.  相似文献   
93.
A 55-year-old man complained of sudden onset of severe neck pain. This was followed by prompt loss of consciousness and death. Autopsy revealed rupture of a saccular aneurysm, which was considered to have resulted from enlargement of the remaining ductal tissue, and was located on the medial aspect of the uppermost portion of the descending aorta. Dense blood extravasation was noted in the posterior mediastinum and extending to the strap muscles of the neck and larynx. Histological examination of the rupture site revealed disappearance of the medial elastic fibers and thickened intima covered with dense fibrous tissue. Spontaneous ductus arteriosus aneurysm in adults is a rare finding, but widespread use of imaging technologies has revealed that it develops more frequently than previously recognized. Fatal complications may occur even when the aneurysm is relatively small. Therefore, pathologists should be aware of this aneurysm as a potential cause of sudden death.  相似文献   
94.
In 2007, the Bureau of Justice Statistics reported on 2004 data collected from the Census of Medical Examiner and Coroner Offices (CMEC). The CMEC was one of the first comprehensive reports on the state of the medicolegal death investigation system in the United States and included information on administration, expenditure, workload, specialized death investigations, records and evidence retention, and resources. However, the report did not include responses on questions that were related to toxicology such as specimen retention and type of testing. The purpose of this publication is to provide the community with toxicology laboratory-specific responses from nearly 2000 medical examiner and coroner (MEC) offices. Data obtained from a BJS CMEC public use dataset for any remaining information that was not reported in the 2007 BJS report were evaluated specific to the operation of toxicology laboratories within a MEC office or specific to toxicology testing. The CMEC includes information on average operating budget for MEC offices with internal or external toxicology services, budget for toxicology/microbiology services, respondents’ routine uses of toxicology analysis, toxicology specimen retention time, average turnaround times, use of computerized information management systems, and participation in federal data collections. These historical data begin to address the present state of our nation’s toxicology laboratories within the medicolegal death investigation system and their preparedness for the current drug overdose epidemic.  相似文献   
95.
Methyl nitrite is suggested to cause methemoglobinemia by generating methemoglobin, which may be lethal when the methemoglobin concentration exceeds 70%. However, intoxication with methyl nitrite is seldom reported compared with that with other nitrites. Here, we present an industrial accident involving methyl nitrite inhalation during its synthesis process that resulted in three fatalities and one survivor. The autopsy revealed conspicuous blue-gray discoloration in various parts of the body, including the skin, airway mucosa, vessels, brain, heart, and among other areas. The toxicological tests on the deceased showed methemoglobin concentrations in the blood over the lethal level and increased nitrite ion levels in the blood, gastric contents, liver, and lung tissue compared with those in control samples. The cause of death was determined to be methemoglobinemia-induced hypoxia due to methyl nitrite inhalation. This report provides evidence that in methyl nitrite intoxication, exposure duration has a significant influence on the postmortem changes and likelihood of a fatal outcome may be related to the age of the victim. More attention is required regarding the industrial hazards of this substance.  相似文献   
96.
In the case of suspicious deaths, the technique of 1:1 taping is often used in Belgium. It consists of affixing a large number of adhesive tapes to the body of the victim. It is conventionally aimed at obtaining microtraces (e.g., fibers, hair) and is usually not used for DNA analysis. However, in some cases, DNA analysis of certain areas of interest identified on the 1:1 taping material can offer a last resort solution. The four-step method that is described in this article involves the selection of areas of interest on the body (Step 1), the selection of the corresponding tapes (Step 2), the decontamination of the tapes (Step 3), the selection of areas of interest on the tapes, for DNA sampling (Step 4). The method is illustrated by its successful application in four murder cases. In each case, DNA profiles of good quality could be identified, including profiles of persons different from the victim.  相似文献   
97.
对需要在尸体检验时进行颈椎多层螺旋CT(MSCT)检查的情形进行讨论,研究利用MSCT对疑有颈椎损伤的尸体进行颈椎检查的方法,并对一例疑似颈椎损伤尸体的颈椎提取后进行MSCT检查。发现对疑似有颈椎骨折尸体提取颈椎进行MSCT检查,可以快速精确地显示颈椎的细微骨折及骨折的空间分布,从而推断致伤方式。解决了传统尸检中费时费力,容易漏诊和误诊的问题。  相似文献   
98.
法医精神病鉴定在刑事、民事和行政三大诉讼领域中,以鉴定意见的证据形式发挥着重要作用。然而,与其重要性不相匹配的是,法医精神病鉴定学科发展尚不完善、专业发育尚不成熟,尚不能满足社会和民众的期盼和要求,甚至引发负面评价。为进一步促进法医精神病鉴定规范化、标准化建设。以法医精神病鉴定人的视角,结合法医精神病鉴定的内容架构,重点阐述法医精神病鉴定主要项目及其作用、评定要点,尤其聚焦刑事责任能力评定,阐明当前存在分歧和困难;简要介绍法医精神病鉴定人执业要求、法医精神病鉴定质量控制;以及简述法医精神病鉴定与临床精神医学实践的区别与联系。  相似文献   
99.
法医精神病鉴定是一种经验型或技能型鉴定类型,大多数鉴定项目只能依靠鉴定人的经验进行判断,质量控制更显重要。遗憾的是,目前该专业并未像其他法医类鉴定那样实行认证认可制度,质量控制手段不多。为有效保障鉴定质量,必须围绕鉴定意见形成过程的各个阶段或环节进行过程控制与监督,重点关注“人、机、料、法、环”等要素。为此,建议在该行业内逐步恢复认证认可制度,完善质量体系建设,运用好各种内外部质量控制方法,严格把关鉴定人准入,实行鉴定人执业分类管理、强化鉴定人执业能力考核,以规范行业鉴定活动,维护行业司法鉴定的公信力。  相似文献   
100.
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