全文获取类型
收费全文 | 1031篇 |
免费 | 31篇 |
专业分类
各国政治 | 82篇 |
工人农民 | 50篇 |
世界政治 | 73篇 |
外交国际关系 | 68篇 |
法律 | 507篇 |
中国政治 | 7篇 |
政治理论 | 260篇 |
综合类 | 15篇 |
出版年
2021年 | 13篇 |
2020年 | 13篇 |
2019年 | 18篇 |
2018年 | 25篇 |
2017年 | 35篇 |
2016年 | 40篇 |
2015年 | 19篇 |
2014年 | 26篇 |
2013年 | 165篇 |
2012年 | 26篇 |
2011年 | 42篇 |
2010年 | 44篇 |
2009年 | 38篇 |
2008年 | 39篇 |
2007年 | 51篇 |
2006年 | 32篇 |
2005年 | 28篇 |
2004年 | 30篇 |
2003年 | 36篇 |
2002年 | 39篇 |
2001年 | 20篇 |
2000年 | 27篇 |
1999年 | 15篇 |
1998年 | 14篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 9篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 11篇 |
1988年 | 12篇 |
1987年 | 7篇 |
1986年 | 14篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1980年 | 10篇 |
1979年 | 7篇 |
1977年 | 7篇 |
1976年 | 9篇 |
1975年 | 4篇 |
1974年 | 6篇 |
1973年 | 4篇 |
1972年 | 6篇 |
1970年 | 6篇 |
1966年 | 4篇 |
1965年 | 4篇 |
排序方式: 共有1062条查询结果,搜索用时 15 毫秒
71.
72.
73.
Until recently, physicians were viewed as the dominant player in health policy. Now, however, they compete with many other effective interest groups. This article analyzes this changing role, and specifically how organized medicine has changed its approach to influencing health policy. The essay begins with a review of the reasons for the growth and subsequent decline of physicians' influence. This is followed by a case study of physician payment reform under Medicare, which illustrates the ways in which organized medicine chooses when and when not to cooperate with government. The article concludes with a discussion of where physicians are likely to continue to be influential in future health policy reform. Three such areas are noted: payment policy, quality and clinical innovation, and medical education and training. 相似文献
74.
Schmidt P Schmolke C Musshoff F Menzen M Prohaska C Madea B 《Forensic science international》2003,133(3):204-211
In animal experiments and in cell culture, chronic morphine treatment has been followed by "up-regulation" as well as "down-regulation" of the mu-opioid receptor (OR) number. The present postmortem morphometric study of morphine-related fatalities of drug-addicts (n=13, 20-35 years old, with blood unconjugated morphine levels from 27.1 ng/ml to 458 ng/ml, m.v. 198.5 ng/ml) versus a non-addicted control group (n=13, 10-44 years old) was intended to examine, whether chronic opiate exposure affects the numerical density of mu-OR expressing neurons in the human neocortex (areas 11, 24 and 25 according to Brodmann). For the immunohistochemical procedure, vibratome sections (100 microm) were incubated with a monoclonal antibody against the mu-OR, diluted 1:100, and immunolabelled sites were visualized using an immunoperoxidase protocol. The numerical densities of OR immunoreactive neuronal profiles and Nissl-stained central profiles were assessed morphometrically (camera lucida-drawings). In both groups, the anti-mu-OR-immunoreactivity was mainly localized in pyramidal neurons of layers (L) II/III and V and in multiform neurons of L VI. In the areas 24 and 25, the density of the immunoreactive neuronal profiles did not display a significant difference between the two examined groups. In the area 11, however, the number of immunolabelled neuronal profiles amounted to 2777+/-206 mm(3) in the drug-related fatalities and to 2320+/-124 mm(3) in the control group and thus was significantly increased. 相似文献
75.
This article describes a fully automated procedure for detecting cannabinoids in human hair samples. The procedure uses alkaline hydrolysis and headspace solid-phase dynamic extraction (HS-SPDE), followed by on-coating derivatization and gas chromatography-mass spectrometry (GC-MS). SPDE is a further development of solid-phase microextraction (SPME), based on an inside needle capillary absorption trap. It uses a hollow needle with an internal coating of polydimethylsiloxane as extraction and pre-concentration medium.Ten mg of hair were washed with deionised water, petroleum ether and dichloromethane. After adding deuterated internal standards, the sample was hydrolyzed with sodium hydroxide and directly submitted to HS-SPDE. After absorption of analytes for an on-coating derivatization procedure, the SPDE-needle was directly placed into the headspace of a second vial containing N-methyl-N-trimethylsilyl-trifluoroacetamide before GC-MS analysis. The limit of detection was 0.14 ng/mg for Delta(9)-tetrahydrocannabinol, 0.09 ng/mg for cannabidiol, and 0.12ng/mg for cannabinol. Absolute recoveries were in the range of 0.6 to 8.4%. Linearity was verified over a range from 0.2 to 20 ng/mg, with coefficients of correlation between 0.998 and 0.999. Intra- and inter-day precision were determined at two different concentrations and resulted in ranges between 2.3 and 6.0% (intra-day) and 3.3 and 7.6% (inter-day). Compared with conventional methods of hair analysis, this automated HS-SPDE-GC-MS procedure is substantially faster. It is easy to perform without using solvents and with minimal sample quantities, and it yields the same sensitivity and reproducibility. Compared to SPME, we found a higher extraction rate, coupled with a faster automated operation and greater stability of the device. 相似文献
76.
77.
Already the Celts and ancient Germanic peoples knew about the poisonousness of the yew, which played an important part in the mythology of these civilizations. For hunting, the arrows were made poisonous with yew juice, and yew leaves were used for homicide and suicide. In modern times taxine is rarely used with suicidal intent, although this method is actually recommended on the respective Websites. After a 14-year-old boy had intensively studied poisonous plants and methods of suicide on various Websites, he cut leaves from a yew tree (taxus baccata) in his parents' garden, crushed and ingested them and died soon afterwards. At the forensic autopsy pieces of the partially crushed, partially completely preserved yew leaves were found in the stomach. The histological findings were unspecific, e.g. marked general blood congestion of the internal organs and pronounced cerebral and pulmonary edema. When the tree leaves found in the stomach were viewed under the light microscope, a stoma typical of taxus was observed; chemical-toxicological investigations revealed 3,5-dimethoxyphenol in the gastric content, which is considered a marker for the ingestion of taxus. 相似文献
78.
The authors report on a woman who died on the age of 75 years and who was found dead in her dwelling with an extensive injury of the left thigh two days after the last sign of life. Together with the corpse a poodle was present in the dwelling. Due to the unusual localization totally beneath the clothes (trousers) and the morphology of the injury an unnatural cause of death was suspected. According to the autopsy findings and the histological results, postmortal animal scavenging caused by the poodle remained the only explanation for the injury. Supplementary DNA testing yielded final certainty. 相似文献
79.
Jaspers Frank G. W. 《International Environmental Agreements: Politics, Law and Economics》2001,1(3):305-325
Recently, several new pieces of water legislation have been promulgated in both Zimbabwe and the Republic of South Africa. The new acts are an attempt to correct injustices of a colonial past and to trigger development towards effective, equitable and efficient integrated water resources management influenced by the policy decisions in Agenda 21 and the need to respect economic and social human rights. This article aims at identifying and describing factors of prime importance in the process of legal and institutional reform. Major factors are earmarked and derived from the proceedings in Zimbabwe and are compared with the situation in South Africa. Thorough analysis by the author of proceedings, preambles, memoranda, legislation and addenda has induced roughly 5 major reform issues: The call for equitable water distribution based on a widely consented water resources management strategy; The need for effective and efficient integrated water resources management conducive to stakeholder participation through decentralisation processes; The redressing of legal shortcomings in former water legislation with the emphasis on the introduction of integrated approaches; The introduction of instruments of cost recovery for water resources management; The need to develop human resources capacity and institutional strength within the implementing agencies.For both Southern African states, these issues appear to be of comparable importance as major triggers for legal and institutional reform, although not always in the same sense.The resulting most important legal and institutional changes are presented, discussed and compared. Finally, prospects for and constraints on implementation of the new water legislation in these countries are compared. 相似文献
80.
Research and clinical reports on men who are aggressive towards their intimate partners find that these men tend to behave in highly controlling ways towards such partners (e.g., restricting their social interactions, monitoring of activities, and reducing decision-making power). This study tests the hypothesis that men and women in violent dating relationships appraise such behaviors differently than individuals in nonviolent relationships. Based on clinical and empirical partner abuse literature, 119 college students rated the extent to which they perceived hypothetical behaviors towards a partner as controlling. Results suggest that individuals who had either engaged in or received partner aggression appraised restrictive, domineering, and coercive behaviors from a male to a female partner, and from a female to a male partner as less controlling than individuals who had neither perpetrated nor received partner aggression. Men also viewed those behaviors as less controlling than did women. Generalizability, clinical implications, and directions for future research are discussed. 相似文献