全文获取类型
收费全文 | 155篇 |
免费 | 7篇 |
国内免费 | 42篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 5篇 |
2014年 | 13篇 |
2013年 | 9篇 |
2012年 | 11篇 |
2011年 | 15篇 |
2010年 | 9篇 |
2009年 | 12篇 |
2008年 | 11篇 |
2007年 | 15篇 |
2006年 | 10篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 7篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1993年 | 1篇 |
1990年 | 4篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有204条查询结果,搜索用时 46 毫秒
1.
P G Chistyakov M N Abdukayumov A G Veniaminova S N Vladimirov D M Graifer S A Kazakov G G Karpova 《FEBS letters》1988,236(1):246-250
The cleavable homobifunctional reagent dichloro[N,N,N',N'-tetrakis(2-aminoethyl)-1,6-hexamethylenediamminedi platinum (II)] dichloride was used for studying rRNA-protein cross-links in free 35S-labelled 70 S ribosomes and within initiation complex ribosome.AUGU6.fMet-tRNA(fMet). It was shown that the sets of proteins cross-linked to 16 S and 23 S rRNA in free 70 S ribosomes and in 70 S initiation complex do not differ significantly. The authors are the first to demonstrate most of the 23 S rRNA-protein cross-links and some 16 S rRNA-protein cross-links, in particular those with L7/L12 protein. 相似文献
2.
Affinity labelling of Escherichia coli ribosomes with a benzylidene derivative of AUGU6 within initiation and pretranslocational complexes 总被引:2,自引:0,他引:2
G T Babkina A G Veniaminova S N Vladimirov G G Karpova V I Yamkovoy V A Berzin E J Gren I E Cielens 《FEBS letters》1986,202(2):340-344
Affinity labelling of E. coli ribosomes with the 2',3'-O-[4-(N-2-chloroethyl)-N-methylamino]benzylidene derivative of AUGU6 was studied within the initiation complex (complex I) obtained by using fMet-tRNAMetf and initiation factors and within the pretranslocational complex (complex II) obtained by treatment of complex I with the ternary complex Phe-tRNAPhe.GTP.EF-Tu. Both proteins and rRNA of 30 S as well as 50 S subunits were found to be labelled. Sets of proteins labelled within complexes I and II differ considerably. Within complex II, proteins S13 and L10 were labelled preferentially. On the other hand, within complex I, multiple modification is observed (proteins S4, S12, S13, S14, S15, S18, S19, S20/L26 were found to be alkylated) despite the single fixation of a template in the ribosome by interaction of the AUG codon with fMet-tRNAMetf. 相似文献
3.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
4.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
5.
6.
Structure-function analysis of mononucleotides and short oligonucleotides in the priming of enzymatic DNA synthesis 总被引:2,自引:0,他引:2
G A Nevinsky A G Veniaminova A S Levina V N Podust O I Lavrik E Holler 《Biochemistry》1990,29(5):1200-1207
The reversed-phase chromatography technique was employed in the measurement of DNA synthesis at the primers d(pT)n, r(pU)n, d(pA)n, and r(pA)n (n = 1-16) in the presence of template poly(dA) or poly(dT). DNA synthesis was catalyzed by Escherichia coli DNA polymerase I Klenow fragment, Physarum polycephalum DNA polymerase beta-like, P. polycephalum DNA polymerase alpha, and human placenta DNA polymerase alpha. Values of Km and Vmax were measured as functions of the primer chain lengths. It was found that all mononucleotides and small oligonucleotides served as primers of DNA synthesis. Values of the logarithm of both Km and Vmax increased linearly until primers had attained a chain length of 9-12 nucleotides, where a break was observed. The incremental as well as the absolute values of Km were interpreted in terms of free binding energies. These together with other data indicate that the 3'-ultimate nucleotide of the primer contributes a decisive amount of free energy of binding to DNA polymerase both from the nucleoside and from the phosphate moiety. The incremental increase is due to a complementary interaction between bases of primer and template buried in the binding cleft of the polymerase. It is also the ultimate nucleotide that determines whether the ribonucleotide or the deoxyribonucleotide is an efficient primer. It is of interest that the major results seem preserved for all four DNA polymerases. An energetic model for the binding of the template-primer was proposed and compared with available crystallographic data. 相似文献
7.
报道了小菇科小菇属真菌10个中国新记录种,香菌组:橙盖小菇Mycena aurantiidisca、黄白小菇Mycena flavoalba、粉黄小菇Mycena floridula;棘刺组:异刺小菇Mycena heteracantha;纤柄组:碱味小菇Mycena amygdalina;脆足组:粉被小菇Mycena zephirus;冬生组:绣线菊小菇Mycena speirea、冬生小菇Mycena hiemalis;小菇组:绒柄小菇Mycena flos-nivium,分别来自吉林等11个省份、自治区。提供了每个物种的形态描述和线条图,以及与相近种的讨论。共计90条自测及下载ITS序列,在采用贝叶斯法和最大似然法构建的小菇属系统发育树中,新记录种均得到分子数据支持。凭证标本存放于吉林农业大学菌物标本馆(HMJAU)。 相似文献
8.
9.
本文通过Aβ25-35诱导体外原代培养的SD乳大鼠海马神经元,建立Aβ毒性损伤细胞模型,结合AnnexinV-FITC/PI荧光双染法流式细胞术、MTT比色法、实时荧光定量PCR及Western blot方法检测川芎嗪(tetrameth-ylpyrazine,TMP)对原代培养的海马神经元细胞活性、早期凋亡率和Bax、Bcl-2基因表达的影响。结果显示川芎嗪高、中剂量可明显增强细胞活性,增加神经元细胞的存活率(P<0.01),可显著抑制海马神经元细胞早期凋亡(P<0.01),抑制凋亡蛋白Bax的表达(P<0.01),增强抗凋亡蛋白bcl-2的表达(P<0.01)。川芎嗪可通过调节Bax/Bcl-2平衡抵抗Aβ25-35诱导的海马神经元凋亡,降低Aβ的神经元毒性,对海马神经元损伤有明显的保护作用。 相似文献
10.