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961.
You HJ Oh DH Choi CY Lee DG Hahm KS Moon AR Jeong HG 《Biochimica et biophysica acta》2002,1573(1):33-38
Metallothionein (MT)-III is a member of a brain-specific MT family, in contrast to MT-I and MT-II that are found in most tissues and are implicated in metal ion homeostasis and as an antioxidant. To investigate the defensive role of MT-III in terms of hydroxyl radical-induced DNA damage, we used purified human MT-III. DNA damage was detected by single-strand breaks of plasmid DNA and deoxyribose degradation. In this study, we show that MT-III is able to protect against the DNA damage induced by ferric ion-nitrilotriacetic acid and H(2)O(2), and that this protective effect is inhibited by the alkylation of the sulfhydryl groups of MT-III by treatment with EDTA and N-ethylmaleimide. MT-III was also able to efficiently remove the superoxide anion, which was generated from the xanthine/xanthine oxidase system. These results strongly suggest that MT-III is involved in the protection of reactive oxygen species-induced DNA damage, probably via direct interaction with reactive oxygen species, and that MT-III acts as a neuroprotective agent. 相似文献
962.
Dong Y Hakimi MA Chen X Kumaraswamy E Cooch NS Godwin AK Shiekhattar R 《Molecular cell》2003,12(5):1087-1099
We have isolated a holoenzyme complex termed BRCC containing BRCA1, BRCA2, and RAD51. BRCC not only displays increased association with p53 following DNA damage but also ubiquitinates p53 in vitro. BRCC36 and BRCC45 are novel components of the complex with sequence homology to a subunit of the signalosome and proteasome complexes. Reconstitution of a recombinant four-subunit complex containing BRCA1/BARD1/BRCC45/BRCC36 revealed an enhanced E3 ligase activity compared to that of BRCA1/BARD1 heterodimer. In vivo, depletion of BRCC36 and BRCC45 by the small interfering RNAs (siRNAs) resulted in increased sensitivity to ionizing radiation and defects in G2/M checkpoint. BRCC36 shows aberrant expression in sporadic breast tumors. These findings identify BRCC as a ubiquitin E3 ligase complex that enhances cellular survival following DNA damage. 相似文献
963.
STORM (systematic tailored ORF-data retrieval and management) combines protein analyses of BLAST, Fasta, Pfam and ProtParam on a batch file of protein sequences. It subsequently summarises and organises the output in an Access database format. 相似文献
964.
Xue F Qi YP Joshua MN Lan P Dong CY 《Journal of biochemistry and molecular biology》2003,36(3):275-281
An E1B-defective adenovirus, named r2/Ad carrying the neo expression cassette, was constructed by homologous recombination. The construction, selection (using neomycin as a selective marker), and propagation of the recombinant virus was performed in human embryonic kidney 293 cells (HEK 293). An in vitro study demonstrated that this recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as human glioma tumor cells (U251) and human bladder cells (EJ), but not in some cells with functional p53, such as human adenocarcinoma cells (A549) and human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated, under identical conditions, that the U251 cells were more sensitive to r2/Ad replication than the EJ cells. In this paper, we report that r2/Ad could be very useful in studying the in vitro selective replication of E1B-defective adenovirus and has great potential in cancer gene therapy. 相似文献
965.
Jun?Keun?ChangEmail author Yun?Seok?Heo Hyunwoo?Bang Keunchang?Cho Seok?Chung Chanil?Chung Dong?Chul?Han 《Biotechnology and Bioprocess Engineering》2003,8(4):233-239
For the quantitative analysis of an unknown sample a calibration curve should be obtained, as analytical instruments give
relative, rather than absolute measurements. Therefore, researchers should make standard samples with various known concentrations,
measure each standard and the unknown sample, and then determine the concentration of the unknown by comparing the measured
value to those of the standards. These procedures are tedious and time-consuming. Therefore, we developed a polymer based
microfluidic device from polydimethylsiloxane, which integrates serial dilution and capillary electrophoresis functions in
a single device. The integrated microchip can provide a one-step analytical tool, and thus replace the complex experimental
procedures. Two plastic syringes, one containing a buffer solution and the other a standard solution, were connected to two
inlet holes on a microchip, and pushed by a hydrodynamic force. The standard sample is serially diluted to various concentrations
through the microfluidic networks. The diluted samples are sequentially introduced through microchannels by electro-osmotic
force, and their laser-induced fluorescence signals measured by capillary electrophoresis. We demonstrate the integrated microchip
performance by measuring the fluorescence signals of fluorescein at various concentrations. The calibration curve obtained
from the electropherograms showed the expected linearity. 相似文献
966.
Dong?Won?Choi Woo?Gi?Lee Seong?Jin?Lim Byung?Jin?Kim Ho?Nam?ChangEmail author Seung?Teak?Chang 《Biotechnology and Bioprocess Engineering》2003,8(1):23-31
A mathematical model was formulated to simulate the long-term performance of an anaerobic bioreactor designed to digest Korean
food wastes. The system variables of various decomposition steps were built into the model, which predicts the temporal characters
of solid waste, and volatile fatty acid (VFA) in the reactor, and gas production in response to various input loadings and
temperatures. The predicted values of VFA and gas production were found to be in good agreement with experimental observations
in batch and repeated-input systems. Finally, long-term reactor performance was simulated with respect to the seasonal temperature
changes from 5°C in winter to 25°C in summer at different food waste input loadings. The simulation results provided us with
information concerning the success or failure of a process during long-term operation. 相似文献
967.
Kim SH Shin DH Choi IG Schulze-Gahmen U Chen S Kim R 《Journal of structural and functional genomics》2003,4(2-3):129-135
The dramatically increasing number of new protein sequences arising from genomics 4 proteomics requires the need for methods to rapidly and reliably infer the molecular and cellular functions of these proteins. One such approach, structural genomics, aims to delineate the total repertoire of protein folds in nature, thereby providing three-dimensional folding patterns for all proteins and to infer molecular functions of the proteins based on the combined information of structures and sequences. The goal of obtaining protein structures on a genomic scale has motivated the development of high throughput technologies and protocols for macromolecular structure determination that have begun to produce structures at a greater rate than previously possible. These new structures have revealed many unexpected functional inferences and evolutionary relationships that were hidden at the sequence level. Here, we present samples of structures determined at Berkeley Structural Genomics Center and collaborators laboratories to illustrate how structural information provides and complements sequence information to deduce the functional inferences of proteins with unknown molecular functions.Two of the major premises of structural genomics are to discover a complete repertoire of protein folds in nature and to find molecular functions of the proteins whose functions are not predicted from sequence comparison alone. To achieve these objectives on a genomic scale, new methods, protocols, and technologies need to be developed by multi-institutional collaborations worldwide. As part of this effort, the Protein Structure Initiative has been launched in the United States (PSI; www.nigms.nih.gov/funding/psi.html). Although infrastructure building and technology development are still the main focus of structural genomics programs [1–6], a considerable number of protein structures have already been produced, some of them coming directly out of semi-automated structure determination pipelines [6–10]. The Berkeley Structural Genomics Center (BSGC) has focused on the proteins of Mycoplasma or their homologues from other organisms as its structural genomics targets because of the minimal genome size of the Mycoplasmas as well as their relevance to human and animal pathogenicity (http://www.strgen.org). Here we present several protein examples encompassing a spectrum of functional inferences obtainable from their three-dimensional structures in five situations, where the inferences are new and testable, and are not predictable from protein sequence information alone. 相似文献
968.
Choi IG Shin DH Brandsen J Jancarik J Busso D Yokota H Kim R Kim SH 《Journal of structural and functional genomics》2003,4(1):31-34
Journal of Structural and Functional Genomics - 相似文献
969.
This review describes mechanisms of action of artemisinin-related antimalarials, emphasizing the site and target of activation, pathways of generating reactive species, and possible targets of free radicals with implications for antimalarial peroxide drug design. It also presents a useful link between the mode of action of artemisinin and that of chloroquine, and highlights redox cycles involved in the interaction between the drug and vital biomolecules. 相似文献
970.