全文获取类型
收费全文 | 17365篇 |
免费 | 1159篇 |
专业分类
各国政治 | 703篇 |
工人农民 | 832篇 |
世界政治 | 1128篇 |
外交国际关系 | 530篇 |
法律 | 12194篇 |
中国共产党 | 2篇 |
中国政治 | 104篇 |
政治理论 | 2942篇 |
综合类 | 89篇 |
出版年
2023年 | 76篇 |
2021年 | 86篇 |
2020年 | 427篇 |
2019年 | 444篇 |
2018年 | 562篇 |
2017年 | 577篇 |
2016年 | 656篇 |
2015年 | 503篇 |
2014年 | 532篇 |
2013年 | 1794篇 |
2012年 | 481篇 |
2011年 | 501篇 |
2010年 | 533篇 |
2009年 | 559篇 |
2008年 | 507篇 |
2007年 | 499篇 |
2006年 | 520篇 |
2005年 | 433篇 |
2004年 | 429篇 |
2003年 | 352篇 |
2002年 | 402篇 |
2001年 | 671篇 |
2000年 | 602篇 |
1999年 | 479篇 |
1998年 | 238篇 |
1997年 | 171篇 |
1996年 | 191篇 |
1995年 | 189篇 |
1994年 | 168篇 |
1993年 | 175篇 |
1992年 | 304篇 |
1991年 | 311篇 |
1990年 | 294篇 |
1989年 | 276篇 |
1988年 | 304篇 |
1987年 | 261篇 |
1986年 | 320篇 |
1985年 | 316篇 |
1984年 | 247篇 |
1983年 | 226篇 |
1982年 | 177篇 |
1981年 | 154篇 |
1980年 | 144篇 |
1979年 | 220篇 |
1978年 | 115篇 |
1977年 | 91篇 |
1975年 | 94篇 |
1974年 | 124篇 |
1973年 | 79篇 |
1972年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
871.
Schmidt P Schmolke C Musshoff F Menzen M Prohaska C Madea B 《Forensic science international》2000,113(1-3):423-433
In animal experiment and in cell culture, chronic morphine treatment has been followed by a reduction as well as an increase of the delta-opioid receptor (OR) number. The present postmortem morphometric study of morphine-related fatalities of drug addicts (n=12, 22-35 years old, with blood unconjugated morphine levels from 27.1 to 407 ng/ml, m.v. 176.9 ng/ml) versus a non-addicted control group (n=13, 10-44 years old) is intended to examine whether chronic opiate exposure also affects the numerical density of deltaOR expressing neurons in the human neocortex (area 10 according to Brodmann (Vergleichende Lokalisationslehre der Grosshirnrinde (1909) Johann Ambrosius Barth, Leipzig)). For the immunohistochemical procedure, vibratome sections (100 microm) were incubated with a monoclonal antibody against the deltaOR diluted 1:100, and immunoreactive sites were visualized using an immunoperoxidase protocol. The numerical densities of OR expressing and Nissl-stained neurons were assessed morphometrically (camera lucida drawings). In both collectives, the anti deltaOR immunoreactivity was predominantly localized in pyramidal neurons of layers (L) II/III and V as well as in round and ovoid neurons of L VI. In the drug-related fatalities, the density of neurons expressing deltaOR protein amounted for 2515+/-240/mm(3), in the control group for 2616+/-204/mm(3), thus displaying no statistically significant difference. These findings go along with the binding behavior of opioid ligands in postmortem brains of heroin addicts revealing similar receptor densities and affinities in the control subjects and addicts. 相似文献
872.
Zhu BL Oritani S Shimotouge K Ishida K Quan L Fujita MQ Ogawa M Maeda H 《Forensic science international》2000,113(1-3):443-447
To outline the recent features of methamphetamine-related fatalities from the medico-legal point of view, a retrospective investigation of forensic autopsy cases involving methamphetamine during a 5-year period (1994-1998) in the southern half of Osaka city and surrounding areas (about 1.57 million population) was undertaken. Among 646 autopsy cases, methamphetamine was detected in 15 victims (nine males, six females; 16-71 years of age; most frequently in males in their thirties). Primary scenes of fatal events were concentrated in the middle of the city. About half of them were transferred from emergency medical centers (survival time, up to 30 h). The cause and manner of death were: methamphetamine poisoning (n=4), homicide (n=4), accidental falls and aspiration from drug abuse (n=4), fire death (n=1), myocardial infarction (n=1), and cerebral hemorrhage (n=1) under drug influence. Usually injection scars and fresh puncture sites were found. Blood methamphetamine concentrations were 2.29-17.05 micromol/dl in the fatal poisoning, 0. 44-3.80 micromol/dl in deaths from other extrinsic causes (trauma), and 1.35-2.17 micromol/dl in cardio- and cerebrovascular strokes. Common complications were cardiomyopathy, cerebral perivasculitis and liver cirrhosis/interstitial hepatitis. Fatal and nonfatal methamphetamine poisonings are separately dealt with by the administrative medical examiner's office and in emergency medical centers. Tightly cooperative approaches of clinical and medico-legal experts are required for the effective social and medical management of drug abuse. 相似文献
873.
A total of 36 ancient human remains from 12 individuals (three tooth/bone samples each) and one sample each of three individuals from the newest time was typed in a blind study using the amelogenin sex test. Prior to this molecular sex determination the sex of the individual was determined morphologically. The success rate of the amelogenin amplifications was >90%. For every individual an unambiguous molecular sex typing result was obtained. Furthermore, the morphological and molecular sex determinations were in accordance with each other, giving evidence for the authenticity and ancient origin of the polymerase chain reaction (PCR) amplifications. 相似文献
874.
DNA typing is often used to determine identity from human remains. The environment to which the material has been exposed, however, is crucial for the success of the investigation. Damp conditions in particular can cause a rapid degradation of DNA, even in bone and teeth, and thus reduce the chances of successful typing. Here, we present the results of investigations performed on four skulls that had been lying in a damp environment for periods ranging from almost 1 year to about 45 years. In none of these cases was DNA typing successful on bone or, where present, on teeth. Where remnants of brain tissue were used, however, complete STR typing was possible in one case, partial STR typing in another, and mtDNA sequencing could be carried out in three cases. These findings suggest that brain tissue is relatively resistant to putrefaction in damp environments and, unlike bone, appears to exhibit a certain degree of protection against DNA degradation. 相似文献
875.
In four forensic cases of unidentified skeletal remains investigated in the last year, we were able to attach three to missing persons. In one case we could show that the discovered bone sample did not fit to a missing child. The method for mitochondrial DNA analysis for the routine identification of skeletal remains was established in our institute by typing bone samples of defined age obtained from Frankfurt's cemetery. Reproducible results were obtained for bones up to 75 years old. For analysis the bone samples were pulverised to fine powder, decalcified and DNA was extracted. From the DNA we amplified a 404-bp fragment from HV-1 and a 379-bp fragment from HV-2 of the mtDNA control region. After sequencing of the PCR products, the results were compared to the Anderson reference sequence and to putative maternal relatives. 相似文献
876.
A number of DNA polymorphisms have been found to be associated with the pathophysiology of some common disease. If the LDLR polymorphism is directly or indirectly related to some fatal disease, the distribution of the polymorphism may vary with age. We therefore investigated the aging-associated distribution of the LDLR polymorphism. Blood samples were collected from Japanese cadavers (aged 0-91) at autopsy. The LDLR polymorphism was detected using a AmpliType PM PCR Typing kit. When the LDLR genotype was examined in cadavers divided according to age into 0-29 year group, 30-59 year group, and 60-91 year group, there were significant differences in genotype among the three age groups and between the 0-29 year group and 60-91 year group. The LDLR-A genotype tended to be lower in the older cadavers. The present study revealed that there were aging-dependent differences in the distribution of the LDLR polymorphism in autopsy samples, suggesting that a common mutation involved in the occurrence of fatal diseases may be present near the LDLR-A polymorphism locus. 相似文献
877.
Wulf J Bednarz J Junge M Engelmann K Püschel K 《Forensic science international》2000,113(1-3):495-496
Between 1997 and 1999 a steady increase in cornea donations was achieved, but the number of transplantations remained stable because many grafts did not pass quality control. Intermediate organ culture of entire bulbi was examined as a possible solution to reduce post-mortem times and increase suitability for transplantation. 相似文献
878.
879.
880.