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301.
Hwan Young Lee Myung Jin Park Na Young Kim Jeong Eun Sim Woo Ick Yang Kyoung-Jin Shin 《Forensic Science International: Genetics Supplement Series》2010,4(5):275-280
The recovery of DNA data from old skeletal remains is often difficult due to degraded and very low yield of extracted DNA and the presence of PCR inhibitors. Herein, we compared several silica-based DNA extraction methods from artificially degraded DNA, DNA with PCR inhibitors and DNA from old skeletal remains using quantitative real-time PCR. We present a modified large-scale silica-based extraction combined with complete demineralization, that enables maximum DNA recovery and efficient elimination of PCR inhibitors. This is performed with high concentration of EDTA solution for demineralization of bone powder followed by QIAamp® spin columns and buffers from the QIAquick® PCR purification kit. We have successfully used this modified technique to perform STR analysis for 55-year-old skeletal remains. The results of this study will contribute to solve the forensic cases dealing with skeletal remains. 相似文献
302.
林晓萍 《福建公安高等专科学校学报》2003,17(6):90-92
在英语词汇中 ,一词多义现象十分普遍 ,在一词所拥有的多个意思中 ,彼此之间都具有某些方面的联系。以语言学家J .R .Taylor的“家族相似范畴理论”为理论基础 ,再结合实际例句分析、阐述语义范畴的一词多义现象 ,可就其对英语教学的影响与作用有更深入的认识。 相似文献
303.
304.
The application of ultraviolet irradiation to exogenous sources of DNA in plasticware and water for the amplification of low copy number DNA 总被引:2,自引:0,他引:2
Using high sensitivity forensic STR polymerase chain reaction (PCR) typing procedures, we have found low concentrations of DNA contamination in plasticware and water assumed to be sterile, which is not detected by standard DNA procedures. One technique commonly used to eliminate the presence of DNA is ultraviolet (UV) irradiation; we optimized such a protocol used in the treatment of water, tubes, plates, and tips for low copy number DNA (LCN) amplification. UV light from a Stratalinker((R)) 2400 was administered to 0.2, 1.5 mL tubes, and PCR plates contaminated with up to 500 pg of DNA. They were subsequently quantified with an ALU-based real-time PCR method using the Rotorgene 3000. Overall, there was a decrease in concentration of DNA recovered as the duration of treatment increased. Nonetheless, following 45 min of irradiating a PCR plate with 500 pg of DNA, nearly 6 pg were still detected. However, when the plate was raised within an inch of the UV source, less than 0.2 pg of DNA was detected. Additionally, lining the area around the samples with aluminum foil further reduced the amount of time necessary for irradiation, as only 30 min eliminated the presence DNA in the raised PCR plate. Similar experiments were conducted using tubes filled with a solution of DNA and water in equivalent concentrations for 50, 15, and 1.5 mL tubes with comparative results. It is plausible that the aluminum foil increased the amount of reflection in the area thereby enhancing penetration of UV rays through the walls of the plasticware. This protocol was tested for the possibility of inhibitors produced from irradiation of plastic tubes. As our protocols require less irradiation time than previous studies, PCR sensitivity was not affected. Moreover, the lifespan of the UV lamps was extended. Our findings demonstrate that this method is useful as an additional precautionary measure to prevent amplification of extraneous DNA from plasticware and water without compromising the sensitivity of LCN DNA amplifications. 相似文献
305.
POPULATION: Bhargavas (n=120), Chaturvedis (n=120), Brahmins (n=120), Muslim Sunni (n=120), Muslim Shiya (n=120), Kayastha (n=120), Mathurs (n=120), Rastogies (n=120), and Vaish (n=120). 相似文献
306.
Kokoszka JE Cline RE Leisy C Grossweiler LL Word CJ 《Journal of forensic sciences》2006,51(5):1074-1079
An approach for generating DNA profiles when critical samples have been consumed and a power outage occurs during the polymerase chain reaction (PCR) amplification reaction is described. This study demonstrates that a complete and accurate DNA short tandem repeat profile can be obtained: (1) when single source DNA samples are amplified for 26, 27, or 28 cycles using the Profiler Plus and COfiler Amplification Kits after an interruption in amplification, (2) from mock samples when PCR amplification has been interrupted early (after five cycles) or late (after 18 cycles) and the sample is subjected to an additional round of amplification, even after incubation of the sample at room temperature overnight, and (3) from nonprobative casework samples interrupted after approximately 18 cycles of amplification, an overnight incubation at room temperature and subjected to one or two additional rounds of PCR amplification for approximately 26 total cycles. Samples interrupted before five completed cycles and subjected to additional PCR cycles yielded variable results. 相似文献
307.
308.
POPULATION: Almost all the Ewenki are found in HulunBuir Ewenki Autonomous Banner, Inner Mongolia province of China. Some Ewenki are nomads; others are farmers or farmer-hunters. A small number of them are hunters. Its national characters and languages belong to the Altai phylum. 相似文献
309.
POPULATION: A total of 105 unrelated and healthy individuals from the Han ethnic group of Nanning city in south China. 相似文献
310.