全文获取类型
收费全文 | 4468篇 |
免费 | 37篇 |
专业分类
各国政治 | 168篇 |
工人农民 | 32篇 |
世界政治 | 742篇 |
外交国际关系 | 451篇 |
法律 | 2442篇 |
中国共产党 | 74篇 |
中国政治 | 225篇 |
政治理论 | 281篇 |
综合类 | 90篇 |
出版年
2021年 | 26篇 |
2018年 | 22篇 |
2016年 | 17篇 |
2015年 | 20篇 |
2014年 | 108篇 |
2013年 | 28篇 |
2012年 | 288篇 |
2011年 | 253篇 |
2010年 | 99篇 |
2009年 | 106篇 |
2008年 | 269篇 |
2007年 | 280篇 |
2006年 | 297篇 |
2005年 | 242篇 |
2004年 | 245篇 |
2003年 | 243篇 |
2002年 | 262篇 |
2001年 | 185篇 |
2000年 | 173篇 |
1999年 | 85篇 |
1998年 | 33篇 |
1997年 | 41篇 |
1996年 | 39篇 |
1995年 | 47篇 |
1994年 | 76篇 |
1993年 | 60篇 |
1992年 | 52篇 |
1991年 | 58篇 |
1990年 | 32篇 |
1989年 | 35篇 |
1988年 | 112篇 |
1987年 | 28篇 |
1986年 | 30篇 |
1985年 | 37篇 |
1984年 | 39篇 |
1983年 | 28篇 |
1982年 | 21篇 |
1981年 | 38篇 |
1980年 | 33篇 |
1979年 | 38篇 |
1978年 | 18篇 |
1977年 | 41篇 |
1976年 | 34篇 |
1973年 | 19篇 |
1964年 | 27篇 |
1963年 | 26篇 |
1962年 | 42篇 |
1961年 | 19篇 |
1960年 | 22篇 |
1959年 | 30篇 |
排序方式: 共有4505条查询结果,搜索用时 15 毫秒
791.
Zhu BL Ishida K Oritani S Quan L Fujita MQ Maeda H Ogawa M Tanaka N Komura S Tsuji T 《Forensic science international》2001,117(3):205-212
To evaluate the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in fatal poisoning in relation to the effects of drugs and poisons on respiratory function, 42 forensic autopsy cases were examined by scoring the staining intensity. The highest scores of SP-A staining, with dense granular deposits (aggregates) in the intra-alveolar space, were observed in fatalities from pancuronium bromide (muscle relaxant) injection and petroleum (butane) gas inhalation. Poisoning with organophosphate pesticides and arsenic (ingestion) showed a second grade SP-A score. However, The SP-A scores were relatively low in ethanol and sedative-hypnotic intoxication. Carbon monoxide intoxication showed a varied degree of SP-A score, and the aggregated SP-A score tended to be higher in cases of lower blood carboxyhemoglobin concentration. A varied SP-A score was also observed in methamphetamine fatalities, in which the score was relatively low in cases with a higher serum drug level. Increase of SP-A was not always associated with the intra-alveolar effusion or hemorrhages. The above-described observations suggested that the immunohistochemical score of SP-A may be a possible indication for intensity and duration of drug/poison-dependent respiratory distress. 相似文献
792.
Allele frequencies of the 10 STR loci (D16S539, D2S1338, D3S1358, vWA, D18S51, D21S11, D8S1179, D19S433, FGA and TH01) included in the AmpFlSTR SGM Plus kit were determined in 107 unrelated individuals from the eastern section and 108 unrelated individuals from western section of Mediterranean region of Turkey. The expected performance of these loci for personal identification and paternity testing in these populations were estimated. 相似文献
793.
Cardinetti B Ciampini C D'Onofrio C Orlando G Gravina L Ferrari F Di Tullio D Torresi L 《Forensic science international》2004,143(1):1-19
The possibility of detection of lead-antimony-barium aggregates from non-firearm sources is confirmed according to the tests performed on brake pads, and firework and automobile workers. Moreover, information on particles taken from cartridge cases shows the relative feeble importance of the morphology in distinguishing gunshot residues (GSRs). Furthermore, also the presence in the spectrum of other elements (e.g., iron) is not so conclusive. In this panorama, the possibility of discriminating gunshot residue particles from other non-firearm lead-antimony-barium aggregates is investigated: the proposed method is based on X-ray mapping technique--currently applied used in Reparto Carabinieri Investigazioni Scientifiche in Rome, the forensic service of Italian Carabinieri--according to which the spatial distribution of the emission energy of each element of the sample is pictured. Gunshot residues present the same lead-antimony-barium distribution (or at least the same antimony-barium distribution with lead nodules), as some other environmental occupational aggregates do not (different plaques of lead, antimony, and barium). So, X-ray mapping technique can offer a new fundamental evaluation parameter in analysis of gunshot residues with scanning electron microscopy/energy-dispersive (SEM/EDS) spectrometry, and new standards could be considered. 相似文献
794.
Allele frequencies for 11 short tandem repeats (STRs) loci (CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, D16S539, D7S820, D13S317, F13B and LPL) were obtained from a sample of 225 unrelated individuals born in the Entre Ríos state of Argentina. 相似文献
795.
Differences in the succession of insects and other Arthropoda (invertebrate animals with jointed legs), on domestic pig carcasses placed under a roof and under the open sky have been studied in Buenos Aires Province, Argentina (latitude 34 degrees 45'S) in all the seasons of the year. Faunal associations proved different for each treatment in winter: the common bluebottle Calliphora vicina was found in both, but on the sheltered carcass Cochliomyia macellaria and the rare Phaenicia cluvia were found as well. In the fall, the difference between sheltered and unsheltered carcasses was small (six species on the former and five species on the latter); in spring and summer, the difference was negligible. 相似文献
796.
Identification of impurities and statistical classification of methamphetamine tablets (Ya-Ba) seized in Thailand 总被引:4,自引:0,他引:4
Puthaviriyakorn V Siriviriyasomboon N Phorachata J Pan-ox W Sasaki T Tanaka K 《Forensic science international》2002,126(2):105-113
Impurity profiles of methamphetamine tablets seized in Thailand have been investigated. The samples are extracted with small amounts of ethyl acetate under alkaline condition and the extracts are analyzed by capillary gas chromatography. Nine compounds (1,2-dimethyl-3-phenylaziridine, ephedrine, methylephedrine, N-formylmethamphetamine, N-acetylmethamphetamine, N-formylephedrine, N-acetylephedrine, N,O-diacetylephedrie, methamphetamine dimer) are identified as impurities in methamphetamine tablet. Caffeine and ethyl vanillin are also detected as diluents and/or adulterants, and acetylcodeine monoacetylmorphine and diacetylmorphine are contained in many samples. In addition, trans-3,4-dimethyl-5-phenyl-2-oxazolidone is newly found as an impurity. For characterization and comparison of methamphetamine tablet exhibits, intensely and commonly detectable nine peaks are selected as the factor for multivariate analysis. The procedures reported here permit classification of 250 analyzed exhibits into five groups and characterization of classified groups. 相似文献
797.
Genetic diversity study at STR loci in 208 individuals belonging to two backward groups, one caste and one tribal community of Central India called "Chhattisgarh" has been carried out to evaluate significance of Powerplex System loci in human identification and population diversity. Populations are Agharia (72), Satmani (50), Dheria Gond (36) and Teli (50). Fifteen loci (Powerplex 16 Kit) studied are Penta E, D18S51, D21S11, THO1, D3S1358, FGA, TPOX, D8S1179, vWA, Amelogenin, Penta D, CSF1PO, D16S539, D7S820, D13S317 and D5S818. The studied penta nucleotide STR (two) and 13 tetranucleotide (CODIS ) STR are found to be highly polymorphic genetic markers in all studied populations. Most common allele for the four studied population has been found to be same at THO1 (allele 9), D8S1179 (allele 14), CSF1PO (allele 12), Penta E (allele 11) and D16S539 (allele 11). Penta E is found to be most polymorphic (PD=0.89373) among studied 15 STR loci in four populations of Central India. 相似文献
798.
牛的先天性肿瘤报告不多。Misdorp最近复查了动物胎儿和初生动物(10天内)的先天性肿瘤和瘤样物(例如白血球增生)文献,而先天性肾真性瘤在以前(1965)没有报道过。在刊物中报道过二例牛胎儿,估计每例胎儿在第六个月流产。发现一例为多发性的肾外肿瘤,另一例为肾上单一的原发性肿瘤。牛的这两例和人的7月龄胎儿一例是文献中先天性肾真性瘤仅有报道的病例。 相似文献
799.
在塔吉克斯坦与中国建立外交关系的15年中,两个邻国的关系一直呈直线上升式发展.目前两国在政治、经济和人文领域的交往达到了历史最好水平.历史遗留的边界问题已经得到彻底和圆满的解决,开放和互信成为两国和两国人民之间交往的准则. 相似文献
800.
近10年来,中国和拉丁美洲国家的对外直接投资发展十分迅速,并已逐渐成为发展中国家和地区乃至全球范围内的新兴对外投资力量。中国与拉美国家同属于发展中世界,但二者实现开放发展的基础和方式不尽相同,对外直接投资的发展历程和企业能力来源也不同。本文在分析中国和拉美国家对外直接投资在发展趋势、行业分布、区位选择和企业性质多方面特征异同的基础上,通过比较研究二者对外直接投资发展的各阶段历程,解释其在对外直接投资表现特征上的各方面差异,并探究导致其差异形成的内在原因。由于改革开放模式的不同,中国对外投资发展进程具有连续性,而拉美国家则呈现波动性;全球金融危机之后中国和拉美国家对外投资都获得了快速发展的机遇。在对外投资能力上,中国明显集中于大型国有企业,投资领域包括能源、矿产以及广泛的制造业;拉美国家则主要是由实力雄厚的非国有企业所代表,投资领域集中在资源行业和以资源为基础的制造业。 相似文献