全文获取类型
收费全文 | 950篇 |
免费 | 44篇 |
专业分类
各国政治 | 69篇 |
工人农民 | 57篇 |
世界政治 | 103篇 |
外交国际关系 | 49篇 |
法律 | 579篇 |
中国政治 | 4篇 |
政治理论 | 132篇 |
综合类 | 1篇 |
出版年
2023年 | 11篇 |
2022年 | 9篇 |
2021年 | 19篇 |
2020年 | 31篇 |
2019年 | 27篇 |
2018年 | 45篇 |
2017年 | 60篇 |
2016年 | 61篇 |
2015年 | 37篇 |
2014年 | 45篇 |
2013年 | 118篇 |
2012年 | 48篇 |
2011年 | 25篇 |
2010年 | 18篇 |
2009年 | 29篇 |
2008年 | 32篇 |
2007年 | 41篇 |
2006年 | 38篇 |
2005年 | 27篇 |
2004年 | 43篇 |
2003年 | 27篇 |
2002年 | 34篇 |
2001年 | 33篇 |
2000年 | 15篇 |
1999年 | 14篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1977年 | 3篇 |
1975年 | 1篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1971年 | 9篇 |
1970年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有994条查询结果,搜索用时 20 毫秒
51.
52.
Torres MC Osuna E Pérez-Cárceles MD Gómez-Zapata M Luna A 《The American journal of forensic medicine and pathology》2002,23(2):155-158
The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process. 相似文献
53.
54.
55.
Baptista MJ Monsanto PV Pinho Marques EG Bermejo A Avila S Castanheira AM Margalho C Barroso M Vieira DN 《Forensic science international》2002,128(1-2):66-78
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit. 相似文献
56.
Sánchez-Diz P Lareu MV Brión M Skitsa I Carracedo A 《Forensic science international》2002,126(3):265-266
Allele frequencies for the nine STRs included in the AmpFlSTR Profiler Plus kit (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820) were estimated from a sample of 143 unrelated individuals living in different regions of Greece. 相似文献
57.
Joo Resende‐Santos 《拉美政治与社会》2002,44(4):89-126
Argentine-Brazilian relations have undergone a remarkable transformation over the last two decades, from enduring rivalry to cooperation. Dating back to the late 1970s, security cooperation has been a byproduct of two different sets of factors, strategic and military organizational, that propelled the two countries independently but simultaneously toward peaceful settlement. The 1979–80 settlement of disputes over hydroelectric power and nuclear technology not only ended centuries of militarized competition but established the first institutional structures of what is today one of the world's most durable security regimes. 相似文献
58.
59.
Gusmão L González-Neira A Sánchez-Diz P Lareu MV Amorim A Carracedo A 《Forensic science international》2000,112(1):49-57
The amplification of the STR DYS391, using the primers described in the Genome Data Base (GDB: G00-365-251), shows not only an additional band to the Y-specific one in males with a size range of 26 bp less than those of DYS391 locus alleles, but also a polymorphic pattern in females in the same size range as the additional band observed in males. The DYS391 pattern in families reflects a Y-specific linked locus and also a polymorphic X locus with an X-linked pattern of inheritance. A first screening in the X homologous locus allowed the identification of five different alleles. Allele frequencies were explored in different population groups for both the Y locus and the homologous locus in the X chromosome showing a similar allele distribution pattern in the X and Y homologous loci. An alternative reverse primer was designed to amplify the Y-chromosome specific STR in order to improve the specificity and applicability of this system to forensic genetics. Comparative results of the amplification with the new and the previously described primers proved that with this new primer there is a substantial increase in the specificity of the amplification. Moreover, a smaller fragment is amplified with a size out of the range of the alleles of the other Y-STRs usually used in forensic applications, therefore simplifying its inclusion in multiplex systems. 相似文献
60.