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排序方式: 共有72条查询结果,搜索用时 31 毫秒
1.
应用概率统计方法对混沌信号进行非相干检测 总被引:3,自引:0,他引:3
提出一种基于概率统计的方法, 采用最大似然法和贝叶
斯公式, 在Chaos Shift Keying系统的接收端重构发射端混沌映射, 实现混沌信号的非相干检测. 在系统的发送端, 根据所发送的二进制信号对混沌映射系统进行分叉参数调制, 由于混沌信号对参数条件的敏感性, 所以在不同的参数条件下混沌信号有很大不同, 在接收端采用概率统计方法, 对信号发生的概率进行计算, 根据事件发生概率的不同判断接收到的数字信号. 理论推导和计算机仿真结果基本一致. 相似文献
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Stephens PJ Tarpey PS Davies H Van Loo P Greenman C Wedge DC Nik-Zainal S Martin S Varela I Bignell GR Yates LR Papaemmanuil E Beare D Butler A Cheverton A Gamble J Hinton J Jia M Jayakumar A Jones D Latimer C Lau KW McLaren S McBride DJ Menzies A Mudie L Raine K Rad R Chapman MS Teague J Easton D Langerød A;Oslo Breast Cancer Consortium 《Nature》2012,486(7403):400-404
All cancers carry somatic mutations in their genomes. A subset, known as driver mutations, confer clonal selective advantage on cancer cells and are causally implicated in oncogenesis, and the remainder are passenger mutations. The driver mutations and mutational processes operative in breast cancer have not yet been comprehensively explored. Here we examine the genomes of 100 tumours for somatic copy number changes and mutations in the coding exons of protein-coding genes. The number of somatic mutations varied markedly between individual tumours. We found strong correlations between mutation number, age at which cancer was diagnosed and cancer histological grade, and observed multiple mutational signatures, including one present in about ten per cent of tumours characterized by numerous mutations of cytosine at TpC dinucleotides. Driver mutations were identified in several new cancer genes including AKT2, ARID1B, CASP8, CDKN1B, MAP3K1, MAP3K13, NCOR1, SMARCD1 and TBX3. Among the 100 tumours, we found driver mutations in at least 40 cancer genes and 73 different combinations of mutated cancer genes. The results highlight the substantial genetic diversity underlying this common disease. 相似文献
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Montgomery KT Lee E Miller A Lau S Shim C Decker J Chiu D Emerling S Sekhon M Kim R Lenz J Han J Ioshikhes I Renault B Marondel I Yoon SJ Song K Murty VV Scherer S Yonescu R Kirsch IR Ried T McPherson J Gibbs R Kucherlapati R 《Nature》2001,409(6822):945-946
Our sequence-tagged site-content map of chromosome 12 is now integrated with the whole-genome fingerprinting effort. It provides accurate and nearly complete bacterial clone coverage of chromosome 12. We propose that this integrated mapping protocol serves as a model for constructing physical maps for entire genomes. 相似文献
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Triiodothyronine injected daily to pregnant rats for the last week of gestation (50 microgram/100 g b.wt) increased the specific activities of 5 acid glycosidases in the fetal forebrain and cerebellum. Cortisone (50 mg/100 g b.wt) administered in the same period had no effect on cerebellum acid hydrolases, but decreased their activity in the forebrain. 相似文献
6.
Pellegata NS Dieguez-Lucena JL Joensuu T Lau S Montgomery KT Krahe R Kivelä T Kucherlapati R Forsius H de la Chapelle A 《Nature genetics》2000,25(1):91-95
Specialized collagens and small leucine-rich proteoglycans (SLRPs) interact to produce the transparent corneal structure. In cornea plana, the forward convex curvature is flattened, leading to a decrease in refraction. A more severe, recessively inherited form (CNA2; MIM 217300) and a milder, dominantly inherited form (CNA1; MIM 121400) exist. CNA2 is a rare disorder with a worldwide distribution, but a high prevalence in the Finnish population. The gene mutated in CNA2 was assigned by linkage analysis to 12q (refs 4, 5), where there is a cluster of several SLRP genes. We cloned two additional SLRP genes highly expressed in cornea: KERA (encoding keratocan) in 12q and OGN (encoding osteoglycin) in 9q. Here we report mutations in KERA in 47 CNA2 patients: 46 Finnish patients are homozygous for a founder missense mutation, leading to the substitution of a highly conserved amino acid; and one American patient is homozygous for a mutation leading to a premature stop codon that truncates the KERA protein. Our data establish that mutations in KERA cause CNA2. CNA1 patients had no mutations in these proteoglycan genes. 相似文献
7.
In this paper, the oxidative degradation of 2, 4-dichlorophenoxyacetic acid (2, 4-D) using Mn2+/H2O2 reagent under UV irradiation was studied. The results show that 2, 4-D was degraded more completely in Mn2+/H2O2 solution than traditional Fenton solutions. The effects of the concentration of Mn2+, H2O2 and pH were also investigated. And under the optimal condition of 1.48×10−4 mol/L, 8.99×10−5 mol/L and pH 3.38, the formation of ·OH was the most, both the decomposition rate of H2O2 and the degradation rate of 2, 4-D were the fastest. In addition, the photoreaction process was monitored using spin-trapping
electron paramagnetic resonance (EPR), and the results indicated that the oxidative process was predominated mainly by the
hydroxyl radical (·OH) gennerated in the system.
Biography: HUANG Yingping (1964–), Professor, Ph. D., research direction: pollution ecology and water pollution control. 相似文献
8.
Microarray analysis shows that some microRNAs downregulate large numbers of target mRNAs 总被引:11,自引:0,他引:11
Lim LP Lau NC Garrett-Engele P Grimson A Schelter JM Castle J Bartel DP Linsley PS Johnson JM 《Nature》2005,433(7027):769-773
9.
吐哈盆地台南凹陷鲁克沁构造带中的北西走向断层受挤压强烈 ,封闭性好 ;而北东走向断层封闭性差 ,常成为油气运移的良好通道。由于本区断块圈闭的有效性差 ,故不具备大规模聚集稀油的条件 ,但对稠变到一定程度的稠油能起较好的封堵作用。鲁克沁构造带高粘重质油的形成是原油运移和成藏阶段双重稠变作用的结果 ,并且油气的聚集是一个动态的过程。随着原油的逐渐稠变 ,所需要的封堵条件逐渐降低 ,油气的聚集过程才趋于稳定。鲁克沁构造带构造后期变革主要表现在构造幅度的增大 ,而未发生强烈的断裂作用 ,因此 ,前侏罗系油藏得以完好地保存 相似文献
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