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131.
The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons. 相似文献
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DNA芯片技术作为一门新兴的高科技生物技术,显示了它旺盛的生命力和迅猛的发展势头。单核苷酸多态性(SingleNucleotidePolymorphisms,SNPs)是最常见的人类基因组变异类型。它作为一种有效的人类遗传标记,在疾病相关性研究、药物基因组学、法医学、人类进化和迁移等研究中发挥了重要作用。它同DNA芯片技术结合运用也将在法医检验,尤其是亲子鉴定和个人识别中发挥重要作用。本文主要讨论了DNA芯片和SNPs的特点,以及二者联合运用于法医学的价值。 相似文献
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肋软骨及牙髓细胞DNA含量与PMI的相关性 总被引:1,自引:0,他引:1
目的探讨人死后肋软骨及牙髓细胞平均DNA含量与死亡时间(PMI)的相关性,寻求推断PMI的新方法。方法应用细胞图像分析技术分析高温(30~35℃)及低温(15~20℃)环境下人死后0~15d两种组织细胞平均DNA含量的降解情况。结果两种组织细胞平均DNA含量随死后时间的延长而逐步降解,其中低温组牙髓细胞平均DNA含量的降解在死后0~4d内有一个降解平台期。统计分析两组温度下两种组织细胞平均DNA含量与PMI有显著的负相关性(P<0.01)。结论依据两种组织细胞平均DNA含量的降解可进行PMI推断。 相似文献
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灌服毒鼠强诱导大鼠细胞DNA的损伤研究 总被引:1,自引:0,他引:1
目的研究毒鼠强体内染毒后,毒鼠强对大鼠脑细胞、心肌细胞、淋巴细胞DNA的损伤作用。方法选择健康Sprague-Dawley大白鼠20只,分成5组,每组4只,采用灌胃方法使大鼠毒鼠强体内染毒,按0.2,0.1,0.05,0.01mg·kg-1制作大鼠毒鼠强中毒模型,并以灌服生理盐水的健康大鼠为对照,分离实验大鼠的淋巴细胞、心肌细胞和脑细胞,用彗星电泳的方法测定不同浓度毒鼠强中毒后的细胞DNA损伤。结果0.2,0.1,0.05,0.01mg·kg-1剂量组的毒鼠强均可引起大鼠的淋巴细胞、心肌细胞和脑细胞DNA损伤,均与对照组差异有显著性(P<0.01)。结论毒鼠强诱导体内细胞DNA损伤可能是毒鼠强毒性作用机制之一。 相似文献
139.
Niemcunowicz-Janica A Pepinski W Janica JR Skawronska M J JJ Koc-Zorawska E 《Journal of forensic sciences》2007,52(4):867-869
Autolysis and putrefaction are crucial factors responsible for degradation of cells, tissues, and organs. Postmortem changes may assume different course depending on extrinsic and intrinsic conditions. The aim of the study was assessment of environmental effect on typeability of AmpFlSTR SGM Plus loci: D3S1358, VWA, D16S539, D2S1338, D81179, D21S11, D18S51, D19S433, TH01, FGA, and gender marker amelogenin. Brain and thyroid gland tissue specimens collected during autopsies of five persons aged 20-30 years were incubated at 21 degrees C and 4 degrees C in different environmental conditions. DNA was extracted by organic method from tissue samples collected in 7-day intervals and subsequently typed using AmpFlSTR SGM Plus kit and ABI 310. A fast decrease in typeability rate was seen in specimens incubated in peat soil and in sand. Brain tissue samples were typeable in all AmpFlSTR SGM Plus loci within 126 days of incubation at 4 degrees C. Faster DNA degradation was recorded in thyroid gland specimens. In samples with negative genotyping results, no DNA was found by fluorometric quantitiation. 相似文献
140.
Craig Dowden Craig Bennell Sarah Bloomfield 《Journal of Police and Criminal Psychology》2007,22(1):44-56
Despite the immense popularity of offender profiling as both a topic of fascination for the general public as well as an academic
field of study, concerns have been raised about the development of this area of scientific inquiry. The present study provides
a preliminary step towards moving the field forward as it reviews the type and quality of studies dealing with offender profiling
over the past 31 years. Based on a content analysis of 132 published articles, the review indicates that researchers investigating
this phenomenon rarely publish multiple articles, and they are generally reported across many different journals, thereby
making knowledge synthesis and knowledge transfer problematic. In addition, the majority of papers published in the area are
discussion pieces (e.g., discussing what profiling is, how profiles are constructed, and when profiling is useful), despite
the fact that the processes underlying offender profiling are still not well understood. Finally, although peer-reviewed articles
exploring this topic have steadily increased, the statistical sophistication of these studies is sorely lacking, with most
including no statistics or formal analyses of data. Suggestions for future research and recommendations to streamline efforts
in this field are provided based on the results of this review.
相似文献
Craig BennellEmail: |