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81.
Thuy-Ai Nguyen Scott D. Slattery Sung-Hwan Moon Yolanda F. Darlington Xiongbin Lu Lawrence A. Donehower 《DNA Repair》2010,9(7):813-823
Nucleotide excision repair (NER) is the only mechanism in humans to repair UV-induced DNA lesions such as pyrimidine (6-4) pyrimidone photoproducts and cyclobutane pyrimidine dimers (CPDs). In response to UV damage, the ataxia telangiectasia mutated and Rad3-related (ATR) kinase phosphorylates and activates several downstream effector proteins, such as p53 and XPA, to arrest cell cycle progression, stimulate DNA repair, or initiate apoptosis. However, following the completion of DNA repair, there must be active mechanisms that restore the cell to a prestressed homeostatic state. An important part of this recovery must include a process to reduce p53 and NER activity as well as to remove repair protein complexes from the DNA damage sites. Since activation of the damage response occurs in part through phosphorylation, phosphatases are obvious candidates as homeostatic regulators of the DNA damage and repair responses. Therefore, we investigated whether the serine/threonine wild-type p53-induced phosphatase 1 (WIP1/PPM1D) might regulate NER. WIP1 overexpression inhibits the kinetics of NER and CPD repair, whereas WIP1 depletion enhances NER kinetics and CPD repair. This NER suppression is dependent on WIP1 phosphatase activity, as phosphatase-dead WIP1 mutants failed to inhibit NER. Moreover, WIP1 suppresses the kinetics of UV-induced damage repair largely through effects on NER, as XPD-deficient cells are not further suppressed in repairing UV damage by overexpressed WIP1. Wip1 null mice quickly repair their CPD and undergo less UV-induced apoptosis than their wild-type counterparts. In vitro phosphatase assays identify XPA and XPC as two potential WIP1 targets in the NER pathway. Thus WIP1 may suppress NER kinetics by dephosphorylating and inactivating XPA and XPC and other NER proteins and regulators after UV-induced DNA damage is repaired. 相似文献
82.
Jane M. Natividad Xianxi Huang Emma Slack Jennifer Jury Yolanda Sanz Chella David Emmanuel Denou Pinchang Yang Joseph Murray Kathy D. McCoy Elena F. Verdú 《PloS one》2009,4(7)
Background and Aims
Excessive uptake of commensal bacterial antigens through a permeable intestinal barrier may influence host responses to specific antigen in a genetically predisposed host. The aim of this study was to investigate whether intestinal barrier dysfunction induced by indomethacin treatment affects the host response to intestinal microbiota in gluten-sensitized HLA-DQ8/HCD4 mice.Methodology/Principal Findings
HLA-DQ8/HCD4 mice were sensitized with gluten, and gavaged with indomethacin plus gluten. Intestinal permeability was assessed by Ussing chamber; epithelial cell (EC) ultra-structure by electron microscopy; RNA expression of genes coding for junctional proteins by Q-real-time PCR; immune response by in-vitro antigen-specific T-cell proliferation and cytokine analysis by cytometric bead array; intestinal microbiota by fluorescence in situ hybridization and analysis of systemic antibodies against intestinal microbiota by surface staining of live bacteria with serum followed by FACS analysis. Indomethacin led to a more pronounced increase in intestinal permeability in gluten-sensitized mice. These changes were accompanied by severe EC damage, decreased E-cadherin RNA level, elevated IFN-γ in splenocyte culture supernatant, and production of significant IgM antibody against intestinal microbiota.Conclusion
Indomethacin potentiates barrier dysfunction and EC injury induced by gluten, affects systemic IFN-γ production and the host response to intestinal microbiota antigens in HLA-DQ8/HCD4 mice. The results suggest that environmental factors that alter the intestinal barrier may predispose individuals to an increased susceptibility to gluten through a bystander immune activation to intestinal microbiota. 相似文献83.
84.
Zachary P. Cohen Kristian Brevik Yolanda H. Chen David J. Hawthorne Benjamin D. Weibel Sean D. Schoville 《Molecular ecology》2021,30(1):237-254
Contextualizing evolutionary history and identifying genomic features of an insect that might contribute to its pest status is important in developing early detection and control tactics. In order to understand the evolution of pestiferousness, which we define as the accumulation of traits that contribute to an insect population's success in an agroecosystem, we tested the importance of known genomic properties associated with rapid adaptation in the Colorado potato beetle (CPB), Leptinotarsa decemlineata Say. Within the leaf beetle genus Leptinotarsa, only CPB, and a few populations therein, has risen to pest status on cultivated nightshades, Solanum. Using whole genomes from ten closely related Leptinotarsa species native to the United States, we reconstructed a high‐quality species tree and used this phylogenetic framework to assess evolutionary patterns in four genomic features of rapid adaptation: standing genetic variation, gene family expansion and contraction, transposable element abundance and location, and positive selection at protein‐coding genes. Throughout approximately 20 million years of history, Leptinotarsa species show little evidence of gene family turnover and transposable element variation. However, there is a clear pattern of CPB experiencing higher rates of positive selection on protein‐coding genes. We determine that these rates are associated with greater standing genetic variation due to larger effective population size, which supports the theory that the demographic history contributes to rates of protein evolution. Furthermore, we identify a suite of coding genes under positive selection that are putatively associated with pestiferousness in the Colorado potato beetle lineage. They are involved in the biological processes of xenobiotic detoxification, chemosensation and hormone function. 相似文献
85.
García-Posadas L Contreras-Ruiz L López-García A Villarón Álvarez S Maldonado MJ Diebold Y 《Histochemistry and cell biology》2012,137(2):165-176
The purpose of this study was to demonstrate the presence of the receptor for hyaluronan-mediated motility (RHAMM) in human
conjunctival epithelium and in two widely used cell lines from human corneal (HCE) and conjunctival (IOBA-NHC) epithelia.
We compared the distribution of RHAMM proteins and mRNAs in human ocular surface tissues (corneal, limbal and conjunctival),
HCE and IOBA-NHC cell lines, and corneal and conjunctival epithelia primary samples from healthy donors with the previously
identified hyaluronan receptor CD44. We also aimed to determine if soluble CD44 (sCD44) was present in human tears, as it
could have a role in the interaction of the tear fluid with hyaluronan. Protein expression was evaluated by Western blots
and immunofluorescence microscopy. mRNA expression was evaluated by RT-PCR and Q-PCR. sCD44 was analyzed by ELISA in culture
supernatants and in human tears. We describe the expression of RHAMM in human healthy conjunctiva and in HCE and IOBA-NHC
cells at both protein and mRNA levels, and the presence of sCD44 in human tears. Furthermore, we detected CD44 and sCD44 expression
variations in in vitro inflammatory conditions. This study also focused on the necessary caution with which the conclusions
extracted from cell lines should be made, and in the great value of using primary samples as often as possible. 相似文献
86.
Protandrous arrival timing to breeding areas: a review 总被引:7,自引:0,他引:7
Protandry, the earlier arrival of males to breeding areas than females, is a common pattern of sex-biased timing in many animal taxa (e.g. some insects, fish, amphibians, reptiles, birds and mammals). The adaptive significance of protandry is not fully understood and, since the 1970s, at least seven hypotheses for protandry have been proposed. We describe each of these hypotheses and summarize what is known about each. In three of these hypotheses, the relative arrival timing of males and females has no direct fitness consequences for males or females, but selection for different timing in each sex indirectly produces protandry. In the other four hypotheses, the difference between male and female timing has fitness consequences for males or females and selection directly maintains the fitness-maximizing degree of sex-biased timing. The hypotheses are not mutually exclusive, and the degree of multiple mating by males and the occurrence of male territoriality seem to determine the relative importance of each hypothesis. In order to understand the adaptive significance of sex-biased timing, future studies need to consider all the alternatives and to assess the costs and benefits to males of early arrival relative to calendar date, to other males and to females. 相似文献
87.
García-Huante Yolanda Cayetano-Cruz Maribel Santiago-Hernández Alejandro Cano-Ramírez Claudia Marsch-Moreno Rodolfo Campos Jorge E. Aguilar-Osorio Guillermo Benitez-Cardoza Claudia G. Trejo-Estrada Sergio Hidalgo-Lara María Eugenia 《Extremophiles : life under extreme conditions》2017,21(1):175-186
Extremophiles - A hyperthermophilic and thermostable xylanase of 82 kDa (TtXynA) was purified from the culture supernatant of T. terrestris Co3Bag1, grown on carboxymethyl cellulose (CMC),... 相似文献
88.
89.
Gle Corine; Del Amo Yolanda; Bec Beatrice; Sautour Benoit; Froidefond Jean-Marie; Gohin Francis; Maurer Daniele; Plus Martin; Laborde Pierre; Chardy Pierre 《Journal of plankton research》2007,29(11):999-1014
Phytoplankton dynamics were assessed in the macrotidal ecosystemof Arcachon Bay through high-frequency surveys over a 5-yearperiod in order to characterize typology of environmental conditionsat the onset of the productive period. Temporal variations ofhydrological and biological parameters were examined in externaland internal waters of the lagoon, during the winter–springperiods from 1999 to 2003. An additional survey was performedduring winter–spring 2005 in order to study the verticalstructure of the water column. The occurrence of winter phytoplanktonblooms between January and March emerged as a recurrent event.The early onset of the productive period is influenced by thebiological functioning of adjacent Bay of Biscay oceanic waters.It is hypothesized that under a propitious hydrodynamic regime,phytoplankton inocula from the Bay of Biscay enter in the ArcachonBay where cells presumably find favourable conditions for theirfast development. The timing of the onset of those winter bloomsin Arcachon Bay seems to be mainly influenced by the presenceof anticyclonic weather conditions (associated with an increasein incident irradiance) during late winter (i.e. by February),while the water column does not show any particular stabilizationnor stratification liable to facilitate the onset of these blooms.Moreover, these winter blooms dominated by diatoms led to anearly nutrient depletion which could have inevitable consequenceson the structuration of the food web during spring and summer. 相似文献
90.
Vasodilator effects of peptides derived from egg white proteins 总被引:1,自引:0,他引:1
The aim of this work was to investigate the effect of several peptides, identified before and after simulated gastrointestinal digestion of an egg white hydrolysate, on the vascular function, in rat aorta. The sequences IVF, RADHPFL and YAEERYPIL (0.1 mM) induced vasodilatation in intact aortic rings, with the maximum percentage of dilation corresponding to RADHPFL (40.5 ± 7.0%). Two of the end products of the gastrointestinal digestion, RADHP and YPI, also showed vasodilator activity with degrees of relaxation higher than 50%. However, all these peptides failed to induce relaxation in endothelium-denuded aortic rings. The relaxation induced by RADHP was concentration-dependent and it was partially blocked by the nitric oxide synthase inhibitor l-NAME (100 μM) and by the B1 bradykinin receptor antagonist Des-HOE 140 (30 nM), thus showing that it was mediated by NO production through the activation of B1 bradykinin receptors. These findings suggest that these peptides could reduce the vascular resistance and could be used as functional food ingredients in the prevention and treatment of hypertension. 相似文献