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991.
3,4-methylenedioxyamphetamine (MDA) derivatives are increasingly abused central nervous system stimulants with neurotoxic properties. In recent years a number of controlled substance analogs (designer drugs) with high structural variety reached the illegal market making their identification an arduous task. The underivatized compounds give very similar or even virtually identical electron impact mass spectra containing mainly intense C(n)H(2n+2)N(+) immonium ions. Using tandem mass spectrometry (MS-MS) the additional structural information contained in the collision induced dissoziation (CID) mass spectra of molecular ions using electron impact (EI) and especially chemical ionization (CI) allowed an unequivocal differentiation of 18 studied regioisomeric 1-(methylenedioxyphenyl)-2-propanamines and 1-(methylenedioxyphenyl)-2-butanamines.Further synthetic methods are presented for 1-(3,4-methylenedioxyphenyl)-N-propyl-2-butanamine, N-isopropyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and four 1-(2, 3-methylenedioxyphenyl)-2-butanamines. N-alkylated 1-(3, 4-methylenedioxyphenyl)-2-butanamine compounds (e.g. MBDB) are also known to be abused psychoactive agents (entactogenes) without the sympatomimetic effects of the 3,4-methylenedioxyamphetamines. 相似文献
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994.
体外培养FBs损伤模型的建立及细胞免疫组化研究 总被引:2,自引:2,他引:0
首次应用培养人胎肺成纤维细胞 (FBs)损伤模型 ,体外研究创缘FBs合成细胞型纤维连接蛋白 (cellu larfibronectins,cFn)的变化与损伤时间的关系。结果表明 ,损伤使处于静息状态的融合FBs成为具有运动能力和增殖能力的活跃细胞。应用免疫组化ABC法结合图像分析技术 ,观察伤后不同时间创缘FBs内cFn的含量变化。伤后 1h ,可以检测到cFn有变化 ,且在伤后 6h内 ,cFn逐渐增多 ,其变化与损伤时间呈正相关。这对今后应用cFn与损伤时间推断的研究提供了科学依据 ,同时为法医学损伤时间研究开辟了新的途径。 相似文献
995.
996.
997.
The HIV/AIDS epidemic continues to be a leading public health issue in the United States. During the past decade, the epidemic has shifted away from the gay community, although gay and bisexual men continue to be the largest single HIV exposure category. Now, HIV increasingly affects low-income people of colour in urban areas, as well as women. As AIDS becomes more and more a minority, inner-city disease, public focus on the epidemic as a significant social and political issue is waning. While a full survey of current issues in US law is beyond the scope of this article, the focus here is on current issues that are highly relevant to the direction the epidemic appears to be taking. 相似文献
998.
The authors review the Business Judgment Rule as applied to a not-for-profit director's duty of care, with particular emphasis on the different forms of state statutory liability shields that serve to enhance the protections of the Rule. They also examine current trends in enforcement of breach of fiduciary duty of care standards, and provide a series of specific recommendations for not-for-profit boards to consider implementing as a means of increasing the likelihood of affording such protections to individuals serving as directors. 相似文献
999.
Israel W. Charny 《Human Rights Review》2000,1(3):15-39
Conclusion The problem of revisionism, or efforts to deny and censor the incontrovertible history of known genocides, is a growing one.
It is now clear that denial is inevitably a phase of the genocidal process, extending far beyond the immediate politically
expedient denials of governments who are currently engaging in genocidal massacre or have just recently done so—i.e., the
Chinese government's abject denials of the killings of some 5,000 in Tiananmen Square, or the Sri Lanka government's denials
of the state-organized massacre of 5,000 Tamil. Denials of genocide continue long after the event by a variety of groups and
people, including successor governments or successor enemies of the victim people, such as anti-Semites against Jews, Turks
against Armenians, and bigots and celebrants of violence and murder of all sorts. But such denials also occur—and this is
the most perplexing fact—among a variety of not obviously malevolent people, including intellectuals who, in the process of
calling for a better world, effectively exonerate, support, encourage, and participate in denials of a known genocide, implicitly
condoning and even celebrating its occurrence, meanings, and portents for the future. This article is an effort to study and
analyze this latter phenomenon, which has been little recognized. Together with previous essays on the psychology of more
explicit malevolent denials of genocide, the intention is to generate a broader psychological theory of denials of genocide
and revisionism by proposing that there are also a variety of “innocent denials” of the factual reality or significance of
known cases of genocide, and a variety of “innocent disavowals of violence” which in truth celebrate the violence. These “innocent
denials” join with the well-known explicit bigots in creating a vast panorama of dangerous denials of genocides and implicit
calls to new genocides in our world.
The basic thesis of this article has been under development since its first presentation in a plenary address at the Soviet
Academy of sciences in Yerevan, Armenia in 1990 on the occasion of the seventy-fifth anniversary of the Armenian Genocide. 相似文献
1000.
Modeling Duration Dependence 总被引:1,自引:1,他引:0
As applications of duration analysis have burgeoned in politicalscience, scholars have become increasingly aware of the potentialsubstantive importance of duration dependence: the extent towhich the conditional hazards of the events of interest arerising or falling over time. Here I discuss the issue of durationdependence, focusing on the distinction between "spurious" dependencedue to unobserved heterogeneity and "true" duration dependencedue to state dependence in the process of interest. I presenta simple extension of a commonly used parametric duration modeltheWeibull modelwhich allows researchers to assess the influenceof causal variables on the nature and extent of duration dependencein their data. I then illustrate the application of this "generalizedWeibull" model using data on the duration of international alliances. 相似文献