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1.
Evangelia Jockers-Wretou Valya Russanova Christo Venkov 《Molecular biology reports》1988,13(3):123-131
In a recent publication the isolation and some characteristics of an anti-histone 3 monoclonal antibody, 1GB3 were described (Muller et al. FEBS Lett. 182: 459–464, 1985). We now report that the epitope recognized is phylogenetically conserved and located in the N-terminal part of H3, most likely between residues 40 and 50. Using the ELISA technique we found this region to be accessible in chromatin to the monoclonal antibody. The effect of non-ionic detergents on the adsorbtion of chromatin on microtiter plates was studied in this context.Immunological analysis of the reaction of the monoclonal antibody with chromatin by immunoinhibition and immunosedimentation shows that the H3 epitope is accessible in both folded and unfolded chromatin fibre as well as in high- and low-molecular weight oligonucleosomes.Abbreviations BSA
Bovine srum albumin
- mab
Monoclonal antibody
- PBS
Phosphate buffered saline
- PMSF
Phenylmethyl sulfonyl fluoride 相似文献
2.
《Molecular cell》2020,77(6):1265-1278.e7
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《Developmental cell》2022,57(22):2533-2549.e7
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The local chromatin structure of the Shrunken-1 (Sh) gene of maize was probed by analyzing DNase I hypersensitivity. Sh encodes the gene for sucrose synthetase, a major starch biosynthetic enzyme, which is maximally expressed in the endosperm during seed maturation. In addition to general DNase I sensitivity, specific DNase I hypersensitive sites were identified in endosperm chromatin that mapped near the 5 end of the Sh gene. The pattern of hypersensitive sites and their relative sensitivity were altered in other non-dormant tissues that produce little or no enzyme. However, some changes in chromatin structure appear to be independent of Sh gene expression and may reflect general alterations associated with plant development. The chromatin structure of several sh mutations, induced by Ds controlling element insertions, was also analyzed. Although the insertions perturbed expression of the gene, there were no notable effects on local chromatin structure. 相似文献
6.
Summary Chromatin fractions from Friend erythroleukemia cells after induction of differentiation by dimethylsulfoxide (DMSO) were compared in their biochemical characteristics to fractions from uninduced cells. Fractions were prepared by extracting chromatin from nuclei after mild micrococcal nuclease treatment with increasing concentrations of NaCl according to Sanders [1]. This procedure has been found to release chromatin containing hyperacetylated histones preferentially [2]. The fractions obtained by this procedure were analysed in respect to the amount of chromatin released, the amount of histone H1, the degree of acetylation of histone H4, the presence of non-histone proteins and the concentration of transcribed and non-transcribed sequences. It was found that the fractions differ in the amount of histone H1 present, in several non-histone proteins and in the acetylation of histonie H4, regardless whether induced or uninduced cells were analysed. The distribution of transcribed sequences versus non-transcribed sequences among the fractions was the same, demonstrating that this fractionation procedure, although leading to fractions with biochemical differences, is not able to discriminate functional states of chromatin and that the biochemical characteristics of the fractions may be common to both, active as well as inactive states of chromatin. 相似文献
7.
Kenneth A. Marx Ray Kruger Michael J. Clarke 《Molecular and cellular biochemistry》1989,86(2):155-162
The goal of this study is to establish the nature of pentammineruthenium(III) binding to DNA in intact mouse liver nuclei. Also, we wish to determine whether the nucleosomal organization of mouse chromatin has a substantial effect on the relative Ru(III) binding levels of internucleosomal and nucleosomal core DNA. These questions are important because ammineruthenium compounds share chemical and biological properties with the cis-dichlorodiammineplatinum(II) or cisplatin chemotherapeutic agent. Therefore, they represent a potential class of new chemotherapeutic agents. We find that in intact nuclei the predominant DNA binding site for pentammineruthenium(II), followed by air oxidation to pentammineruthenium(III), is N-7 guanine, as is the case with cisplatin. Also, the Ru(III) distribution between internucleosomal and nucleosomal core DNA was found to be nearly identical as probed with three non-specific deoxyribonucleases. 相似文献
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Summary Non-histone chromatin protein (NHCP) fractions were extracted from purified beef thyroid nuclear preparations and tested for the presence of protein kinase activities using several known mediators of thyroid regulation, as well as potential phosphotransferase substrates using purified or partially purified protein kinase activities. The addition of cAMP/3-isobutyl-l-methylxanthine had no effect on NHCP historic kinase activity; the addition of 10 g of the heat-stable cAMP-dependent protein kinase A inhibitor, however, resulted in a 47% reduction in histone H2 kinase activity. Nuclear casein kinase II activity was present in the NHCP fractions as evidenced by the capacity of spermine to stimulate (ED50 = 0.19 mM) and heparin to inhibit (ID50 = 0.09 g/ml) the phosphorylation of casein; further, the phosphotransferase activity could be purified by sequential casein-agarose and spermine-agarose affinity chromatography. Neither calcium-calmodulin nor calcium/phosphatidylserine/diolein had an effect on NHCP casein kinase or histone kinase activities, respectively. The addition of cAMP-dependent protein kinase A catalytic subunit, nuclear casein kinase II, calcium-activated calmodulin-dependent protein kinase and diacylglycerol-activated calcium/phospholipid-dependent protein kinase C activities exhibited distinct phosphorylation patterns when NHCP were used as substrates and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography. We conclude that NHCP fraction from beef thyroid: 1) contains both cAMP-dependent protein kinase A catalytic subunit and nuclear casein kinase II and 2) substrates for cAMP-dependent protein kinase A, calcium-activited calmodulin-dependent protein kinase, protein kinase C, and nuclear casein kinase II.Abbreviations NHCP
Non-Histone Chromatin Proteins
- PK-A
cAMP-Dependent Protein Kinase
- CAMPK
Calcium-Activated Calmodulin-Dependent Protein Kinase
- PK-C
Diacylglycerol-Activated Calcium/phospholipid-dependent Protein Kinase
- NK-11
Nuclear Casein Kinase 11
- CK-G
Cytosolic Casein Kinase G or 11
- PMSF
Phenylmethyl Sulfonyl Fluoride
- PKI
the Heat Stable PK-A Inhibitor (Walsh inhibitor)
- SDS-PAGE
Sodium Dodecylsulfate Polyacrylamide Gel Electrophoresis
- EDTA
Ethylenediamine Tetraacetic Acid
- EGTA
Ethyleneglycol bis- (B-aminoethyl ether) N,N,N,N,-Tetraacetic Acid
- PS
Phosphatidylserine
- DO
1,2-Diolein 相似文献
10.
本文以普通小麦(Triticum aestivum L.)根端分生组织为材料,在透射电镜下对间期细胞核内的集缩染色质的高层次结构进行了研究。在其中观察到直径约为20—25nm、50nm及110—120nm 的不同等级染色线,并且发现直径110—120nm 的染色线是由50nm 的染色线组成的,而直径约50nm 的染色线是由20—25nm 的染色线组成的。对这三个层次染色质结构之间的集缩方式进行了讨论。 相似文献