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991.
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994.
Lawrence A. Farwell 《Cognitive neurodynamics》2012,6(2):115-154
Brain fingerprinting (BF) detects concealed information stored in the brain by measuring brainwaves. A specific EEG event-related potential, a P300-MERMER, is elicited by stimuli that are significant in the present context. BF detects P300-MERMER responses to words/pictures relevant to a crime scene, terrorist training, bomb-making knowledge, etc. BF detects information by measuring cognitive information processing. BF does not detect lies, stress, or emotion. BF computes a determination of “information present” or “information absent” and a statistical confidence for each individual determination. Laboratory and field tests at the FBI, CIA, US Navy and elsewhere have resulted in 0% errors: no false positives and no false negatives. 100% of determinations made were correct. 3% of results have been “indeterminate.” BF has been applied in criminal cases and ruled admissible in court. Scientific standards for BF tests are discussed. Meeting the BF scientific standards is necessary for accuracy and validity. Alternative techniques that failed to meet the BF scientific standards produced low accuracy and susceptibility to countermeasures. BF is highly resistant to countermeasures. No one has beaten a BF test with countermeasures, despite a $100,000 reward for doing so. Principles of applying BF in the laboratory and the field are discussed. 相似文献
995.
Prokaryotic diversity,composition structure,and phylogenetic analysis of microbial communities in leachate sediment ecosystems 总被引:1,自引:0,他引:1
In order to obtain insight into the prokaryotic diversity and community in leachate sediment, a culture-independent DNA-based
molecular phylogenetic approach was performed with archaeal and bacterial 16S rRNA gene clone libraries derived from leachate
sediment of an aged landfill. A total of 59 archaeal and 283 bacterial rDNA phylotypes were identified in 425 archaeal and
375 bacterial analyzed clones. All archaeal clones distributed within two archaeal phyla of the Euryarchaeota and Crenarchaeota,
and well-defined methanogen lineages, especially Methanosaeta spp., are the most numerically dominant species of the archaeal community. Phylogenetic analysis of the bacterial library
revealed a variety of pollutant-degrading and biotransforming microorganisms, including 18 distinct phyla. A substantial fraction
of bacterial clones showed low levels of similarity with any previously documented sequences and thus might be taxonomically
new. Chemical characteristics and phylogenetic inferences indicated that (1) ammonium-utilizing bacteria might form consortia
to alleviate or avoid the negative influence of high ammonium concentration on other microorganisms, and (2) members of the
Crenarchaeota found in the sediment might be involved in ammonium oxidation. This study is the first to report the composition
of the microbial assemblages and phylogenetic characteristics of prokaryotic populations extant in leachate sediment. Additional
work on microbial activity and contaminant biodegradation remains to be explored. 相似文献
996.
Wei Zhou Jianyi Zhu Songdong Shen Shan Lu Jinfeng Wang Jianrong Xu Pu Xu 《Journal of applied phycology》2008,20(5):991-999
Nuclear divisions of carpospores, conchocelis and conchospores of Porphyra yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. oligospermatangia from China were investigated. The observations showed diploid chromosome numbers of 2n = 6 for P. yezoensis and P. oligospermatangia, and 2n = 10 for P. haitanensis and P. katadai var. hemiphylla. For all four species, somatic pairing of chromosome sets was observed in late prophase. Sister chromosomes separated at
anaphase as mitosis took place in carpospores, conchocelis filamentous cells, conchosporangial branch cells and sporangial
cells (conchospore formation). Chromosome configurations of tetrad and ring-shaped in conchospore germination were observed,
demonstrating the occurrence of meiosis. The characteristics of diploid nuclear division in 2n = 6 species are the same as
those of 2n = 10 species. The influence of somatic pairing on nuclear division of diploid cells in Porphyra was discussed. 相似文献
997.
Jiazhang Lian Shinghua Ding Jin Cai Danping Zhang Zhinan Xu Xiaoning Wang 《Applied microbiology and biotechnology》2009,82(3):463-470
Aquaporin Z (AqpZ), a typical orthodox aquaporin with six transmembrane domains, was expressed as a fusion protein with TrxA
in E. coli in our previous work. In the present study, three fusion partners (DsbA, GST and MBP) were employed to improve the expression
level of this channel protein in E. coli. The result showed that, compared with the expression level of TrxA-AqpZ, five- to 40-fold increase in the productivity of
AqpZ with fusion proteins was achieved by employing these different fusion partners, and MBP was the most efficient fusion
partner to increase the expression level. By using E. coli C43 (DE3)/pMAL-AqpZ, the effects of different expression conditions were investigated systematically to improve the expression
level of MBP-AqpZ in E. coli. The high productivity of MBP-AqpZ (200 mg/l) was achieved under optimized conditions. The present work provides a novel
approach to improve the expression level of membrane proteins in E. coli. 相似文献
998.
Wendy González Leandro Zú?iga L. Pablo Cid Barbara Arévalo María Isabel Niemeyer Francisco V. Sepúlveda 《The Journal of biological chemistry》2013,288(8):5984-5991
Proton-gated TASK-3 K+ channel belongs to the K2P family of proteins that underlie the K+ leak setting the membrane potential in all cells. TASK-3 is under cooperative gating control by extracellular [H+]. Use of recently solved K2P structures allows us to explore the molecular mechanism of TASK-3 cooperative pH gating. Tunnel-like side portals define an extracellular ion pathway to the selectivity filter. We use a combination of molecular modeling and functional assays to show that pH-sensing histidine residues and K+ ions mutually interact electrostatically in the confines of the extracellular ion pathway. K+ ions modulate the pKa of sensing histidine side chains whose charge states in turn determine the open/closed transition of the channel pore. Cooperativity, and therefore steep dependence of TASK-3 K+ channel activity on extracellular pH, is dependent on an effect of the permeant ion on the channel pHo sensors. 相似文献
999.
Neurovascular injury comprises a wide spectrum of pathophysiology that underlies the progression of brain injury after cerebral
ischemia. Recently, it has been shown that activation of the integrin-associated protein CD47 mediates the development of
blood–brain barrier injury and edema after cerebral ischemia. However, the mechanisms that mediate these complex neurovascular
effects of CD47 remain to be elucidated. Here, we compare the effects of CD47 signaling in brain endothelial cells, astrocytes,
and pericytes. Exposure to 4N1 K, a specific CD47-activating peptide derived from the major CD47 ligand thrombospondin-1,
upregulated two major neurovascular mediators, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9),
in brain endothelial cells and astrocytes. No changes were detected in pericytes. These findings may provide a potential mechanism
for CD47-induced changes in blood–brain barrier homeostasis, and further suggest that CD47 may be a relevant neurovascular
target in stroke. 相似文献
1000.
A proteomics approach was used to search for novel phospholipid binding proteins in Saccharomyces cerevisiae. Phospholipids were immobilized on a solid support and the lipids were probed with soluble yeast protein extracts. From this, the phosphatidic acid binding proteins were eluted and identified by mass spectrometry. Thirteen proteins were identified and 11 of these were previously unknown lipid binding proteins. The protein-lipid interactions identified would not have been predicted using bioinformatics approaches as none possessed a known lipid binding motif. A subset of the identified proteins was purified to homogeneity and determined to directly bind phospholipids immobilized on a solid support or organized into liposomes. This simple approach could be systematically applied to perform an exhaustive screen for soluble lipid binding proteins in S. cerevisiae or other organisms. 相似文献