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861.
Hou‐Ling Wang Jinhuan Chen Qianqian Tian Shu Wang Xinli Xia Weilun Yin 《Physiologia plantarum》2014,152(3):529-545
Populus euphratica is the only arboreal species that is established in the world's largest shifting‐sand desert in China and is well‐adapted to the extreme desert environment, so it is widely considered a model system for researching into abiotic stress resistance of woody plants. However, few P. euphratica reference genes (RGs) have been identified for quantitative real‐time polymerase chain reaction (qRT‐PCR) until now. Validation of suitable RGs is essential for gene expression normalization research. In this study, we screened 16 endogenous candidate RGs in P. euphratica leaves in six abiotic stress treatments, including abscisic acid (ABA), cold, dehydration, drought, short‐duration salt (SS) and long‐duration salt (LS) treatments, each with 6 treatment gradients. After calculation of PCR efficiencies, three different software tools, NormFinder, geNorm and BestKeeper, were employed to analyze the qRT‐PCR data systematically, and the outputs were merged by means of a non‐weighted unsupervised rank aggregation method. The genes selected as optimal for gene expression analysis of the six treatments were RPL17 (ribosomal protein L17) in ABA, EF1α (elongation factor‐1 alpha) in cold, HIS (histone superfamily protein H3) in dehydration, GIIα in drought and SS, and TUB (tubulin) in LS. The expression of 60S (the 60S ribosomal protein) varied the least during all treatments. To illustrate the suitability of these RGs, the relative quantifications of three stress‐inducible genes, PePYL1, PeSCOF‐1 and PeSCL7 were investigated with different RGs. The results, calculated using qBasePlus software, showed that compared with the least‐appropriate RGs, the expression profiles normalized by the recommended RGs were closer to expectations. Our study provided an important RG application guideline for P. euphratica gene expression characterization. 相似文献
862.
Wang Y Li SJ Pan J Che Y Yin J Zhao Q 《Biochemical and biophysical research communications》2011,(2):353-359
The newly discovered human voltage-gated proton channel Hv1 is essential for proton transfer, which contains a voltage sensor domain (VSD) without a pore domain. We report here for the first time that Hv1 is specifically expressed in the highly metastatic human breast tumor tissues, but not in poorly metastatic breast cancer tissues, detected by immunohistochemistry. Meanwhile, real-time RT-PCR and immunocytochemistry showed that the expression levels of Hv1 have significant differences among breast cancer cell lines, MCF-7, MDA-MB-231, MDA-MB-468, MDA-MB-453, T-47D and SK-BR-3, in which Hv1 is expressed at a high level in highly metastatic human breast cancer cell line MDA-MB-231, but at a very low level in poorly metastatic human breast cancer cell line MCF-7. Inhibition of Hv1 expression in the highly metastatic MDA-MB-231 cells by small interfering RNA (siRNA) significantly decreases the invasion and migration of the cells. The intracellular pH of MDA-MB-231 cells down-regulated Hv1 expression by siRNA is obviously decreased compared with MDA-MB-231 with the scrambled siRNA. The expression of matrix metalloproteinase-2 and gelatinase activity in MDA-MB-231 cells suppressed Hv1 by siRNA were reduced. Our results strongly suggest that Hv1 regulates breast cancer intracellular pH and exacerbates the migratory ability of metastatic cells. 相似文献
863.
Jingchao H Rong S Zhongchen S Lan C 《Biochemical and biophysical research communications》2011,(3):437-441
Extracts of enamel matrix proteins are used to regenerate periodontal tissues. Amelogenin, the most abundant enamel protein, plays an important role in the regeneration of these tissues. However, the molecular mechanisms by which amelogenin contributes to periodontal regeneration remain unknown. Using primary human bone marrow stroma cells (hBMSCs) transduced with lentivirus encoding human amelogenin (hAm), we performed genome-wide expression profiling to analyze the effects of hAm transduction on the regulation of genes involved in osteogenic differentiation. Our results revealed that BMP-2, BMP-6, OPN and VEGFC were up-regulated. These results suggest that hAm may be a key element in regulating hBMSCs osteogenic differentiation. 相似文献
864.
The reaction of Ni(ClO4)2·6H2O with 3,5-dichloro-2-hydroxy-benzylaminoacetic acid (H2dchaa), NaN3 and triethylamine in methanol solution or water solution under solvothermal methods leads to the formation of two completely different NiII compounds: [HN(C2H5)3]8·[Ni4(dchaa)4(N3)4]2 (1) and [HN(C2H5)3]2·[Ni3(dchaa)4(H2O)4]2·(H2O)2 (2). The complexes 1 and 2 have been characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. Structure analyses reveal that complex 1 is a cubane cluster, while the complex 2 is a linear trinuclear cluster. The magnetic investigation shows that complexes 1 and 2 exhibit a ferromagnetic coupling between NiII ions. Ac susceptibilities of 1 and 2 reveal no frequency-dependent out-of-phase signals and the corresponding magnetic properties were discussed. 相似文献
865.
Li A Geng J Cui D Shu C Zhang S Yang J Xing J Wang J Ma F Hu S 《Journal of bacteriology》2011,193(19):5531
Agrobacterium tumefaciens F2 is an efficient bioflocculant-producing bacterium. But the genes related to the metabolic pathway of bioflocculant biosynthesis in strain F2 are unknown. We present the draft genome of A. tumefaciens F2. It could provide further insight into the biosynthetic mechanism of polysaccharide-like bioflocculant in strain F2. 相似文献
866.
Bian F Qin QL Xie BB Shu YL Zhang XY Yu Y Chen B Chen XL Zhou BC Zhang YZ 《Journal of bacteriology》2011,193(24):7006-7007
Glaciecola nitratireducens strain FR1064(T) was isolated from seawater and described as a new species by Baik et al. in 2006. The genome size is about 1.01 to 1.26 Mb smaller than two reported Glaciecola genomes, indicating the gain or loss of large genome segments in the evolution of Glaciecola strains. 相似文献
867.
Wang SD Zhu F Yuan S Yang H Xu F Shang J Xu MY Jia SD Zhang ZW Wang JH Xi DH Lin HH 《Planta》2011,234(1):171-181
Salicylic acid (SA) is required for plant systemic acquired resistance (SAR) to viruses. However, SA-deficient plants adapt to RNA virus infections better, which show a lighter symptom and have less reactive oxygen species (ROS) accumulation. The virus replication levels are higher in the SA-deficient plants during the first 10?days, but lower than the wild-type seedlings after 20?dpi. The higher level of glutathione and ascorbic acid (AsA) in SA-deficient plants may contribute to their alleviated symptoms. Solo virus-control method for mortal viruses results in necrosis and chlorosis, no matter what level of virus RNAs would accumulate. Contrastingly, early and high-dose AsA treatment alleviates the symptom, and eventually inhibits virus replication after 20?days. ROS eliminators could not imitate the effect of AsA, and could neither alleviate symptom nor inhibit virus replication. It suggests that both symptom alleviation and virus replication control should be considered for plant virus cures. 相似文献
868.
Aletris simpliciflora R. Li & S. D. Zhang, a new species of Nartheciaceae from southwest Xizang, China, is described and illustrated. It is similar, and apparently closely related, to A. nana S. C. Chen, but differs by having usually solitary flower, pubescent bract and bracteole, and distinct filaments ca 1.2 mm long. 相似文献
869.
870.