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   2900篇
  免费   113篇
各国政治   231篇
工人农民   95篇
世界政治   295篇
外交国际关系   194篇
法律   1125篇
中国政治   13篇
政治理论   984篇
综合类   76篇
  2023年   10篇
  2022年   10篇
  2021年   23篇
  2020年   46篇
  2019年   55篇
  2018年   97篇
  2017年   83篇
  2016年   103篇
  2015年   59篇
  2014年   75篇
  2013年   450篇
  2012年   97篇
  2011年   99篇
  2010年   74篇
  2009年   83篇
  2008年   94篇
  2007年   115篇
  2006年   77篇
  2005年   105篇
  2004年   95篇
  2003年   75篇
  2002年   84篇
  2001年   74篇
  2000年   74篇
  1999年   58篇
  1998年   49篇
  1997年   48篇
  1996年   51篇
  1995年   44篇
  1994年   41篇
  1993年   35篇
  1992年   43篇
  1991年   47篇
  1990年   45篇
  1989年   41篇
  1988年   34篇
  1987年   19篇
  1986年   24篇
  1985年   25篇
  1984年   24篇
  1983年   22篇
  1982年   30篇
  1981年   38篇
  1980年   28篇
  1979年   13篇
  1978年   14篇
  1977年   11篇
  1975年   12篇
  1974年   12篇
  1967年   7篇
排序方式: 共有3013条查询结果,搜索用时 15 毫秒
201.
This ecological study examined the association between seven socioeconomic indicators (GDP, unemployment rate, female labor force participation rate, alcohol expenditure, marriage rate, percentage of births outside of marriage, and indictable crime rate) and total, male, and female rates of suicide and suicide plus undetermined death in Ireland during the period 1968-2000. Analysis of the data expressed as absolute values showed highly significant associations between the socioeconomic indicators and the total, male, and female suicide rates. However, these associations were explained by the strongly trended data. The trended nature of the data was removed by using year-to-year differences. Analysis of the first-differenced data showed that none of the socioeconomic indicators was associated with the total, male, or female suicide rates with the exception of indictable crime, which had a significant independent effect on the female suicide rate (coefficient = 2.0, p < .01) but not on suicide plus undetermined death. This study highlights the need to use econometric methods in time-trend analyses, the lack of age-sex specific exposure data in this area, and the challenge of understanding trends in suicide in their socioeconomic context.  相似文献   
202.
A mobile and fast, semi-automatic ultrasound (US) system was developed for facial soft tissue depth registration. The system consists of an A-Scan ultrasound device connected to a portable PC with interfacing and controlling software. For 52 cephalometric landmarks, the system was tested for repeatability and accuracy by evaluating intra-observer agreement and comparing ultrasound and CT-scan results on 12 subjects planned for craniofacial surgery, respectively. A paired t-test evaluating repeatability of the ultrasound measurements showed 5.7% (n = 3) of the landmarks being significantly different (p < 0.01). US and CT-scan results showed significant differences (p < 0.01) using a Wilcoxon signed rank test analysis for 11.5% (n = 6) of the landmarks. This is attributed to a difference in the volunteer's head position between lying (CT) and sitting (US). Based on these tests, we conclude that the proposed registration system and measurement protocol allows relatively fast (52 landmarks/20 min), non-invasive, repeatable and accurate acquisition of facial soft tissue depth measurements.  相似文献   
203.
Infectious microorganisms are important to multiple communities engaged in biodefense and biosecurity, including the agencies responsible for health, defense, law enforcement, agriculture, and drug and food safety. Many agencies have created lists of high priority infectious microorganisms to prioritize research efforts or to formally control the possession and distribution of specific organisms or toxins. However, the biological classification of infectious microorganisms is often complex and ambiguous, leading to uncertainty and confusion for scientists involved in biosecurity work. To address this problem, we created a database, known as the Microbial Rosetta Stone, which resolves many of these ambiguities and includes links to additional information on the microbes, such as gene sequence data and scientific literature. Here we discuss the efforts to coordinate organism names from pathogen lists from various governmental agencies according to biological relatedness and show the overlap of high-priority organisms from multiple agencies. To our knowledge, this is the first comprehensive coordination of pathogens, synonyms, and correct taxonomic names. The organized tables and visual aids are freely available at http://www.microbialrosettastone.com. This website provides a single location where access to information on a broad range of disease-causing organisms and toxins is available to members of the biosecurity community.  相似文献   
204.
The effects of an intramural cognitive-behavioral treatment for forensic inpatients with personality disorders in a high-security hospital were examined. Treatment was aimed at modifying maladaptive coping and social skills, at enhancing social awareness, at reducing egoistic and oppositional behaviors, and at reducing psychological complaints. The patients, who all had committed serious crimes (violence, arson, sexual offences), participated voluntarily in the study. A total of 39 patients started the study, but during the course of the study, several patients dropped out because of several reasons. Patients as a group showed significant improvements over time on psychopathological symptoms, personality traits, and coping. A significant decrease of oppositional behaviors was reported by the staff. Though the patients improved well at the group level, only a minority of patients showed reliable change over time at the individual level. The meaning of the results in relation to treatment are discussed.  相似文献   
205.
206.
207.
Relationships among Structured Interview of Reported Symptoms (SIRS) scores and Minnesota Multiphasic Personality Inventory--2 (MMPI-2) F(p) and F scores were examined for 63 suspected malingerers evaluated at either of two psychiatric facilities. Despite differences between facilities in terms of seriousness of subjects' offenses, mean scores on the malingering tests were similar. Cutting scores for F(p) and F resulting in substantial correspondence between these scales and the SIRS were derived. Use of the cut score for F(p) proposed by Arbisi and Ben-Porath (1995) resulted in less agreement with the SIRS than did a lower cut score. No substantial difference between F(p) and F in each scale's overall agreement with the SIRS was observed. A principal components analysis of the SIRS primary scales produced two factors, interpreted as Overreporting of Symptoms and Implausible Symptoms. F(p) was observed to correlate significantly with Implausible Symptoms but not with Overreporting of Symptoms; F was significantly correlated with both factors.  相似文献   
208.
Suffocation by inhaled gases has been reported involving a variety of gases. We report a case of suicidal asphyxiation by forced replacement of oxygen with helium by using a complex homemade mask. In this case, a young woman researched suicide on the Internet and found an advocated method of suicide using helium. To our knowledge, there is only 1 previously reported case of suicidal asphyxia by using helium.  相似文献   
209.
There has been an increased focus on child custody evaluations involving domestic violence allegations with much criticism of evaluators' training, practices, and procedures. A national survey of 115 child custody evaluators (doctoral and master's level) was conducted to explore these criticisms. Findings revealed adequate training, multiple sources of data collection, and practices/procedures that closely adhere to child custody guidelines. However, robust, specialized domestic violence instruments, tests, and questionnaires were underutilized. Respondents indicated that findings supporting domestic violence allegations had a substantial impact on their subsequent recommendations. Results are discussed in terms of the importance of assessing domestic violence when conducting custody evaluations and the need for developing practice standards in this domain. Generally, results did not support common criticisms of custody evaluation practice.  相似文献   
210.
This article argues that existing Australian regulations do not adequately cover online pharmacies or Internet advertising of medicines and that existing penalties and sanctions are often ineffective, potentially placing public health and safety at risk. Suggestions are made for future regulatory approaches. It is concluded that as well as an effective program of public education, cautious domestic legislative reform is necessary to ensure specific regulation of Australian online pharmacy practice and Internet advertising of medicines. In addition, the global nature of the Internet demands international co-operation and increased regulator and consumer vigilance.  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