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241.
A dependable and efficient wildlife species identification system is essential for swift dispensation of the justice linking wildlife crimes. Development of molecular techniques is befitting the need of the time. The forensic laboratories often receive highly ill-treated samples for identification purposes, and thus, validation of any novel methodology is necessary for forensic usage. We validate a novel multiplex polymerase chain reaction assay, developed at this laboratory for the forensic identification of three Indian crocodiles, Crocodylus palustris, Crocodylus porosus, and Gavialis gangeticus, following the guidelines of Scientific Working Group on DNA Analysis Methods. The multiplex PCR was tested for its specificity, reproducibility, sensitivity, and stability. This study also includes the samples treated with various chemical substances and exposed to various environmental regimes. The result of this validation study promises this technique to be an efficient identification tool for Indian crocodiles and therefore is recommended for forensic purposes. 相似文献
242.
DNA-based analysis is integral to missing person identification cases. When direct references are not available, indirect relative references can be used to identify missing persons by kinship analysis. Generally, more reference relatives render greater accuracy of identification. However, it is costly to type multiple references. Thus, at times, decisions may need to be made on which relatives to type. In this study, pedigrees for 37 common reference scenarios with 13 CODIS STRs were simulated to rank the information content of different combinations of relatives. The results confirm that first-order relatives (parents and fullsibs) are the most preferred relatives to identify missing persons; fullsibs are also informative. Less genetic dependence between references provides a higher on average likelihood ratio. Distant relatives may not be helpful solely by autosomal markers. But lineage-based Y chromosome and mitochondrial DNA markers can increase the likelihood ratio or serve as filters to exclude putative relationships. 相似文献
243.
Almog J Sheratzki H Elad-Levin M Sagiv AE Singh GD Jasuja OP 《Journal of forensic sciences》2011,56(Z1):S162-S165
We explored the quality distribution of ninhydrin-developed prints on A4 bond paper in two groups of individuals, in Israel and in India. While the quality distributions of the developed marks in both countries had some dissimilarities, both groups showed the expected bell-shape distribution, with the majority of the donors belonging to the central zone, defined as "average" or "good." Attempt was made to correlate between a physiological feature, palmar moisture, and the fingerprint donorship. As a rule, high fingermark quality could be associated with sweating hands, but there were individuals with moist palms whose fingermarks had a low score and vice versa. This finding supports the logical but hitherto unproven assumption that besides the amount of palmar sweat, the other physiological factor governing the prints' quality is the total amount of substrate, amino acids in this case, in the latent deposits, which depends on the substrate concentration in the sweat. 相似文献
244.
Bond JW 《Journal of forensic sciences》2011,56(4):999-1002
From an examination of the fingerprint sweat corrosion of 40 different individuals on α phase brass, we show that an increase in visualization can be achieved by applying a negative potential to the brass followed by the introduction of a conducting powder. Previously, this technique has been demonstrated only for a positive applied potential and a corrosion product that was dominated by p-type copper (I) oxide. X-ray photoelectron and Auger electron spectroscopic analyses of the surface of the corroded brass show that an increase in visualization with a negative applied potential corresponds with an increase in the concentration of n-type zinc oxide relative to p-type copper (I) oxide with the Cu:Zn ratio <0.8:1. Work function conditions for the formation of an n-type zinc oxide/brass rectifying Schottky barrier are fulfilled. 相似文献
245.
Laser detection of latent fingerprints on a white paper has been performed, previously. Ultraviolet fluorescence from various kinds of printer toner and ink used for home printers were measured to study fluorescence imaging of fingerprints on a color-printed white paper. The experimental system consisted of a nanosecond pulsed tunable laser and a cooled CCD camera. Excitation wavelengths are 230 and 280 nm. Fourteen printers consisting of three color laser printers, three color inkjet printers, five monochrome laser printers, two monochrome copy machines, and a color copy machine were tested. Toner and ink of most printers exhibited fluorescence in the region from 360 to 550 nm. In most cases, clear fluorescence images were obtained by time-resolved imaging with a band-pass filter and 280-nm excitation. However for toners from laser color printers that showed strong fluorescence, better results were obtained with 230-nm excitation. Latent fingerprints on a photograph page and a black-character page of a newspaper were also imaged. 相似文献
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不同人所讲的普通话语流中相邻音素间的过渡方式分为不同的类型。音节内辅音-元音之间、音节间元音-辅音之间的过渡方式分为清晰过渡(或停顿过渡)和模糊过渡(或缓冲过渡)两种类型;音节内元音-辅音之间的过渡方式分为间断过渡和连续过渡两种类型;音节内元音-元音之间的过渡方式分为平滑过渡、间断过渡、交错过渡和异变过渡四种类型。对同一人的发音而言,不论其相邻音素间的过渡方式属于上述哪种类型,都表现出较强的自身同一性。因此音素间的过渡方式可以作为声纹鉴定中的一类特征。 相似文献
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