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51.
Zhong Yujie Jin Chengni Han Jiahui Zhu Jiachang Liu Qi Sun Dianjun Xia Xiaodong Peng Xiaoli 《Cell biology and toxicology》2021,37(5):795-809
Cell Biology and Toxicology - 3-Chloro-1, 2-propanediol (3-MCPD) is a food-borne toxic substance well-known for more than 40 years that is mainly associated with nephrotoxicity. A better... 相似文献
52.
Ruiqi Liu Tingting Chen Xiao Yin Gaoqing Xiang Jing Peng Qingqing Fu Mengyuan Li Boxing Shang Hui Ma Guotian Liu Yuejin Wang Yan Xu 《The Plant journal : for cell and molecular biology》2021,106(6):1557-1570
Pathogens secrete a large number of effectors that manipulate host processes to create an environment conducive to pathogen colonization. However, the underlying mechanisms by which Plasmopara viticola effectors manipulate host plant cells remain largely unclear. In this study, we reported that RXLR31154, a P. viticola RXLR effector, was highly expressed during the early stages of P. viticola infection. In our study, stable expression of RXLR31154 in grapevine (Vitis vinifera) and Nicotiana benthamiana promoted leaf colonization by P. viticola and Phytophthora capsici, respectively. By yeast two-hybrid screening, the 23-kDa oxygen-evolving enhancer 2 (VpOEE2 or VpPsbP), encoded by the PsbP gene, in Vitis piasezkii accession Liuba-8 was identified as a host target of RXLR31154. Overexpression of VpPsbP enhanced susceptibility to P. viticola in grapevine and P. capsici in N. benthamiana, and silencing of NbPsbPs, the homologs of PsbP in N. benthamiana, reduced P. capcisi colonization, indicating that PsbP is a susceptibility factor. RXLR31154 and VpPsbP protein were co-localized in the chloroplast. Moreover, VpPsbP reduced H2O2 accumulation and activated the 1O2 signaling pathway in grapevine. RXLR31154 could stabilize PsbP. Together, our data revealed that RXLR31154 reduces H2O2 accumulation and activates the 1O2 signaling pathway through stabilizing PsbP, thereby promoting disease. 相似文献
53.
Neospora caninum, an obligate intracellular parasite of the phylum Apicomplexa, is a major cause of abortion in cattle. After invasion, tachyzoites can reside in the parasitophorous vacuole (PV) and ingest nutrition through the intravacuolar network (IVN). Secreted dense granule proteins of N. caninum (NcGRAs) may play important roles in maintaining the structures of the PV and IVN. In this study, we predicted a NcGRA12 gene; aligned it with Toxoplasma gondii GRA12 for homology analysis; and analyzed the ORF, signal peptide and transmembrane domain. Then, we cloned the NcGRA12 gene, expressed the NcGRA12 protein, prepared polyclonal antibodies, and carried out colocalization analysis of NcGRA12 with NcGRA6 in extracellular tachyzoites and intracellular PVs using an immunofluorescence assay (IFA). Finally, we determined the solubility of the NcGRA12 protein. The results showed that NcGRA12 shared 59.13% nucleotide homology and 44.9% amino acid homology with TgGRA12. There was no predicted signal peptide or transmembrane domain. IFA data of extracellular tachyzoites showed that the NcGRA12 protein was secreted by the apical organ and located at the posterior end of tachyzoites, which was consistent with TgGRA12. IFA data of intracellular PVs identified NcGRA12 in the IVN membranes. Moreover, NcGRA12 could colocalize with NcGRA6 in intracellular PVs but not extracellular tachyzoites. Solubility analysis showed that NcGRA12 existed in soluble and membrane-related forms in the PV. Overall, we provide the first report of the novel NcGRA12 protein and verify that it is associated with the IVN membranes of PVs in N. caninum. These data lay a foundation for further research into the function of NcGRA12. 相似文献
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55.
Success in ecological restoration is rarely assessed rigorously due to insufficient planning for post-restoration monitoring programs, limited funding and, especially, lack of scientifically validated evaluation criteria and protocols. In this article, we propose the use of the Indicator Value Index technique (IndVal), which statistically determines the association of species to one or several particular site types, to obtain indicators of success at the early stages of the recovery process in restoration projects. Peat bogs extracted by the vacuum method, subsequently restored by a moss-transfer technique and regularly monitored for ~10 years were used as a model system to test this approach. We first identified 34 restored sectors of ~10 ha from 4 to 11 years old in twelve eastern-Canadian bogs. These sectors were then classified according to their degree of success in recovering a typical sphagnum moss carpet (restoration goal). Then, we retrospectively reviewed vegetation communities recorded at the third year after restoration to identify indicator species of different categories of restoration success, using the IndVal methodology. By identifying early indicator species, our method provides a tool that guides intervention soon after restoration if a site is not on a desired successional trajectory. Typical bog species, namely the bryophytes S. rubellum and Mylia anomala and the tree Picea mariana, were indicative of successful restoration; while bare peat, lichens and one species of ericaceous shrubs (Empetrum nigrum), which cope better under drier conditions, indicated sites where restoration failed. A surprising finding was that the moss Polytrichum strictum, which is known to facilitate the colonization of sphagnum in disturbed peatlands, is an early indicator of unsuccessful restoration. This finding made us question the nursing role of P. strictum at a cover threshold above ca. 30%, when P. strictum could be outcompeting sphagnum and become dominant. We conclude that the IndVal method is an effective tool to identify early indicators of restoration success when combined with a thoughtful examination of species frequency and cover within each site type. 相似文献
56.
Aims
To purify and primarily characterize an anti‐Alicyclobacillus bacteriocin produced by Bifidobacterium animalis subsp. animalis CICC 6165, suggested to be named bificin C6165.Methods and Results
During purification of the bificin C6165, optimal recovery was achieved with ammonium sulfate precipitation followed by two chromatographic steps. Mass spectrometry analyses revealed a distinctive peak corresponding to a molecular mass of 3395·1 Da. This bacteriocin was heat stable, effective after refrigerated storage and freeze–thaw cycles. The primary mode of action of bificin C6165 is most probably due to pore formation, as indicated by the efflux of K+ from metabolically active cells of Alicyclobacillus acidoterrestris. In the presence of 10 mmol l?1 gadolinium, bificin C6165 did not affect cells of Alicyclobacillus acidoterrestris. This suggests that the mode of action of bificin C6165 relies on a net negatively charged cell surface.Conclusions
Bificin C6165 is indeed a novel bacteriocin and it exhibited remarkable potency for Alicyclobacillus control.Significance and Impact of the Study
Application of bacteriocins in preservation of fruit juices has seldom been studied. Bificin C6165 may be an alternative method to control juice spoilage by this Alicyclobacillus acidoterrestris and meet increasing consumer demand for nature and artificial chemical additive‐free food products. 相似文献57.
Junxiang Zhang Huixia Li Mingke Zhang Maixia Hui Qi Wang Li Li Lugang Zhang 《Molecular breeding : new strategies in plant improvement》2013,32(4):799-805
Orange head Chinese cabbage accumulates significant amounts of carotenoids with enhanced nutritional quality. To develop molecular markers for breeding of Chinese cabbage lines with high carotenoid content and to isolate the candidate gene underlying carotenoid synthesis, we performed fine mapping of the orange locus in a F2S4 mapping population. Genetic analysis revealed that the phenotype of the orange head trait was controlled by a single recessive gene, Br-or. The F2S4 mapping population consisting of 1,724 individuals was developed from the cross between parental lines 11J16 and 11S39-2 by continuous selfing of a single heterozygous individual. Twenty-one tightly linked simple sequence repeat (SSR) and insertion/deletion polymorphism (InDel) markers were obtained. High-resolution genetic mapping of these markers in the F2S4 mapping population placed Br-InDel2 and Br-InDel1 at genetic distances of 0.1 and 0.2 cM, respectively, on either side of the Br-or locus. Based on comparison of these two marker sequences with the fully sequenced Brassica rapa genome, the Br-or locus was delimited to a 16.7 kb genomic region. Three open reading frames (ORFs) were predicted in the target region. ORF1 encoded carotenoid isomerase, which is involved in the isomerization of carotenoids. ORF1 was found to be co-segregated with the Br-or locus and was thus the most likely candidate gene for Br-or. The information obtained here will facilitate the breeding of nutrient-enriched Chinese cabbage through marker-assisted selection and provide a platform for gaining a better understanding of the regulation of carotenoid biosynthesis in these plants. 相似文献
58.
Yufeng Cheng Qian Wang Zhanjie Li Jianmin Cui Shengwu Hu Huixian Zhao Mingshun Chen 《PloS one》2013,8(11)
Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility in rapeseed (Brassica napus L.). To understand MES-induced male sterility in rapeseed better, comparative cytological and proteomic analyses were conducted in this study. Cytological analysis indicated that defective tapetal cells and abnormal microspores were gradually generated in the developing anthers of MES-treated plants at various development stages, resulting in unviable microspores and male sterility. A total of 141 differentially expressed proteins between the MES-treated and control plants were revealed, and 131 of them were further identified by MALDI-TOF/TOF MS. Most of these proteins decreased in abundance in tissues of MES-treated rapeseed plants, and only a few increased. Notably, some proteins were absent or induced in developing anthers after MES treatment. These proteins were involved in several processes that may be crucial for tapetum and microspore development. Down-regulation of these proteins may disrupt the coordination of developmental and metabolic processes, resulting in defective tapetum and abnormal microspores that lead to male sterility in MES-treated plants. Accordingly, a simple model of CHA-MES-induced male sterility in rapeseed was established. This study is the first cytological and dynamic proteomic investigation on CHA-MES-induced male sterility in rapeseed, and the results provide new insights into the molecular events of male sterility. 相似文献
59.
We previously reported the insertion process of the ferrous ion into the protoporphyrin IX from the side of the residue His-183 (J. Inorg. Biochem. 103 (2009) 1680–1686). Sellers et al. suggested that the ferrous ion probably approaches the protoporphyrin IX via the opposite side in the human enzyme. In this paper, we simulated the insertion process of Fe2+ into the protoporphyrin IX from the side of the residue Tyr-13 at the opposite site of His-183 by QM/MM method on Bacillus subtilis ferrochelatase. The model was built with Fe2+ ion coordinated by Tyr-13, His-88 and two water molecules. Geometries were optimized at the BP86/6-31G* level and energies were calculated at the B3LYP/6-311+G(2d,2p) level. The overall process involves the displacement of the residues Tyr-13, His-88 and one water molecule and deprotonation of the porphyrin ring. All the local minimum structures and energy barriers were obtained and an optimal insertion pathway was suggested. The rate-determining step is the removing of the second proton from the porphyrin accompanied by the formation of the fourth Fe-N bond with an energy barrier of 138.00 kJ/mol. 相似文献
60.