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81.
本文概述了人类基因组计划及人类基因组研究的新进展,重点阐述了人类新基因克隆的策略与现状、问题与对策,同时就新基因克隆过程中的技术难点作了概括性的归纳,并就其突破分别提出可行的建设性意见,对从事这方面研究的科研人员具有重要的指导作用。 相似文献
82.
Dr. Jihyun Kim Dr. Mihajlo Novakovic Prof. Dr. Sundaresan Jayanthi Dr. Adonis Lupulescu Dr. Ēriks Kupče Dr. J. Tassilo Grün Klara Mertinkus Andreas Oxenfarth Prof. Dr. Harald Schwalbe Prof. Dr. Lucio Frydman 《Chemphyschem》2022,23(4):e202100704
Hadamard encoded saturation transfer can significantly improve the efficiency of NOE-based NMR correlations from labile protons in proteins, glycans and RNAs, increasing the sensitivity of cross-peaks by an order of magnitude and shortening experimental times by ≥100-fold. These schemes, however, fail when tackling correlations within a pool of labile protons – for instance imino-imino correlations in RNAs or amide-amide correlations in proteins. Here we analyze the origin of the artifacts appearing in these experiments and propose a way to obtain artifact-free correlations both within the labile pool as well as between labile and non-labile 1Hs, while still enjoying the gains arising from Hadamard encoding and solvent repolarizations. The principles required for implementing what we define as the extended Hadamard scheme are derived, and its clean, artifact-free, sensitivity-enhancing performance is demonstrated on RNA fragments derived from the SARS-CoV-2 genome. Sensitivity gains per unit time approaching an order of magnitude are then achieved in both imino-imino and imino-amino/aromatic protons 2D correlations; similar artifact-free sensitivity gains can be observed when carrying out extended Hadamard encodings of 3D NOESY/HSQC-type experiments. The resulting spectra reveal significantly more correlations than their conventionally acquired counterparts, which can support the spectral assignment and secondary structure determination of structured RNA elements. 相似文献
83.
Takamiya T Hosobuchi S Asai K Nakamura E Tomioka K Kawase M Kakutani T Paterson AH Murakami Y Okuizumi H 《Electrophoresis》2006,27(14):2846-2856
Restriction landmark genome scanning (RLGS) is a 2-DE of genomic DNA, which visualizes thousands of loci. In a conventional RLGS method for methylation analysis, we have used a methylation sensitive restriction enzyme, NotI as a landmark. However, it was unable to discriminate methylation polymorphism from sequence polymorphism. Here, we report an improved RLGS method to detect methylated sites directly. We employed isoschizomers, MspI and HpaII, that recognize the same sequence (CCGG) but have different methylation sensitivity. We carried out the RLGS analysis of Arabidopsis thaliana ecotype Columbia, and obtained a pair of spot patterns with MspI and HpaII. We detected 22 spots in both patterns. In comparison of them, 18% of the spots were polymorphic, which indicated the methylation of C(5m)CGG sites. Further analyses revealed an additional methylated site of NotI. Moreover, 52 and 54 restriction enzyme sites were also analyzed in two other ecotypes, Wassilewskija and Landsberg erecta, respectively. Consequently, 15% of the 52 common sites showed methylation polymorphism among the three ecotypes. The restriction sites analyzed in this study were located in or near genes, and contribute new data about the correlation between methylation status and gene expression. Therefore, this result strongly indicates that the improved RLGS method is readily applicable to practical analyses of methylation dynamics, and provides clues to the relationship between methylation and gene expression. 相似文献
84.
85.
人类基因组计划及研究 总被引:1,自引:0,他引:1
朱国萍 《安徽师范大学学报(自然科学版)》1999,22(1):88-90
近年来,采用DNA序列测定、基因克隆、基因组文库的构建等方法对人类基因组进行了研究,完成了大部分人类基因组的物理图谱、转录图谱及单核苷酸多态性图谱的分析。进而发现、克隆和研究了许多新基因,如青光眼基因、肿瘤抑制基因等,这些结果使人类第一次在分子水平上认识自我,并有助于从人灰基因组中去除有害基因。最后本文探讨了人类基因组研究可能带来的问题。 相似文献
86.
从采集到的微量胎盘绒毛,经过组织细胞培养,获得了大量的绒毛细胞,对其进行了基因组DNA的分离纯化,提取到足够量的DNA。经过0.8%琼脂糖凝胶电泳,结果显示出完整的绒毛细胞DNA带,得到了典型的大分子DNA电泳图谱。 相似文献
87.
Huifeng Xi Yuehai Ke Junhua Xiao Hongyu Li Jianzhong Jin Wei Huang Li Jin Daru Lu 《科学通报(英文版)》2002,47(18):1538-1540
It is a new approach to study the important genes related to the control of blood pressure by probing into hypotension and hypertension at the same time. Genome scanning on whole chromosome 2 in 8 hypotension pedigrees has been done and parameter (LOD score) and non-pa- rameter (NPL score) were used in the linkage analysis by GENEHUNTER software. The results show the evidence of linkage between D2S112 and D2S117, indicating a number of critical genes may lie in thisregion and contribute to the mechanism of blood pressure regulation. Also this region has been found in the previous study in hypertension pedigrees. These genes may play an important role in the regulation of blood pressure and can also be the important candidate genes in hypertension studies. 相似文献
88.
香蕉束顶病毒的分子生物学 总被引:1,自引:0,他引:1
孟清 《内蒙古大学学报(自然科学版)》1998,29(4):558-568
香蕉束顶病毒为直径18-20nm的球形粒子,其,基因组至少含有六个约1.0kb的单链环状DNA分子。 相似文献
89.
In this paper, we present a simple and efficient whole genome alignment method using maximal exact match (MEM). The major problem with the use of MEM anchor is that the number of hits in non-homologous regions increases exponentially when shorter MEM anchors are used to detect more homologous regions. To deal with this problem, we have developed a fast and accurate anchor filtering scheme based on simple match extension with minimum percent identity and extension length criteria. Due to its simplicity and accuracy, all MEM anchors in a pair of genomes can be exhaustively tested and filtered. In addition, by incorporating the translation technique, the alignment quality and speed of our genome alignment algorithm have been further improved. As a result, our genome alignment algorithm, GAME (Genome Alignment by Match Extension), performs competitively over existing algorithms and can align large whole genomes, e.g., A. thaliana, without the requirement of typical large memory and parallel processors. This is shown using an experiment which compares the performance of BLAST, BLASTZ, PatternHunter, MUMmer and our algorithm in aligning all 45 pairs of 10 microbial genomes. The scalability of our algorithm is shown in another experiment where all pairs of five chromosomes in A. thaliana were compared. 相似文献
90.
Tzvetkov MV Becker C Kulle B Nürnberg P Brockmöller J Wojnowski L 《Electrophoresis》2005,26(3):710-715
Whole-genome DNA amplification by multiple displacement (MD-WGA) is a promising tool to obtain sufficient DNA amounts from samples of limited quantity. Using Affymetrix' GeneChip Human Mapping 10K Arrays, we investigated the accuracy and allele amplification bias in DNA samples subjected to MD-WGA. We observed an excellent concordance (99.95%) between single-nucleotide polymorphisms (SNPs) called both in the nonamplified and the corresponding amplified DNA. This concordance was only 0.01% lower than the intra-assay reproducibility of the genotyping technique used. However, MD-WGA failed to amplify an estimated 7% of polymorphic loci. Due to the algorithm used to call genotypes, this was detected only for heterozygous loci. We achieved a 4.3-fold reduction of noncalled SNPs by combining the results from two independent MD-WGA reactions. This indicated that inter-reaction variations rather than specific chromosomal loci reduced the efficiency of MD-WGA. Consistently, we detected no regions of reduced amplification, with the exception of several SNPs located near chromosomal ends. Altogether, despite a substantial loss of polymorphic sites, MD-WGA appears to be the current method of choice to amplify genomic DNA for array-based SNP analyses. The number of nonamplified loci can be substantially reduced by amplifying each DNA sample in duplicate. 相似文献