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981.
Hasturk H Kantarci A Goguet-Surmenian E Blackwood A Andry C Serhan CN Van Dyke TE 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(10):7021-7029
Resolvin E1 (RvE1) is a potent proresolving mediator of inflammation derived from omega-3 eicosapentaenoic acid that acts locally to stop leukocyte recruitment and promote resolution. RvE1 displays potent counter-regulatory and tissue-protective actions in vitro and in vivo. Periodontal disease is a local inflammatory disease initiated by bacteria characterized by neutrophil-mediated tissue injury followed by development of a chronic immune lesion. In this study, we report the treatment of established periodontitis using RvE1 as a monotherapy in rabbits compared with structurally related lipids PGE(2) and leukotriene B(4). PGE(2) and leukotriene B(4) each enhanced development of periodontitis and worsened the severity of disease. Promotion of resolution of inflammation as a therapeutic target with RvE1 resulted in complete restoration of the local lesion, and reduction in the systemic inflammatory markers C-reactive protein and IL-1beta. This report is the first to show that resolution of inflammation by a naturally occurring endogenous lipid mediator results in complete regeneration of pathologically lost tissues, including bone. 相似文献
982.
Analyzing growth components in trees 总被引:1,自引:0,他引:1
Guédon Y Caraglio Y Heuret P Lebarbier E Meredieu C 《Journal of theoretical biology》2007,248(3):418-447
Observed growth, as given, for instance, by the length of successive annual shoots along the main axis of a plant, is mainly the result of two components: an ontogenetic component and an environmental component. An open question is whether the ontogenetic component along an axis at the growth unit or annual shoot scale takes the form of a trend or of a succession of phases. Various methods of analysis ranging from exploratory analysis (symmetric smoothing filters, sample autocorrelation functions) to statistical modeling (multiple change-point models, hidden semi-Markov chains and hidden hybrid model combining Markovian and semi-Markovian states) are applied to extract and characterize both the ontogenetic and environmental components using contrasted examples. This led us in particular to favor the hypothesis of an ontogenetic component structured as a succession of stationary phases and to highlight phase changes of high magnitude in unexpected situations (for instance, when growth globally decreases). These results shed light in a new way on botanical concepts such as "phase change" and "morphogenetic gradient". 相似文献
983.
984.
A protocol for the rapid, automated synthesis of oligospermine-oligonucleotide sequences is described. To this end, a protected spermine phosphoramidite derivative was synthesized in six steps from spermine and used as the fifth synthon in an oligonucleotide synthesizer. Parameters were optimized to reach greater than 95% coupling yields. Cationic oligonucleotides show enhanced hybridization and strand invasion properties, and hence are an alternative to conventional oligonucleotides for molecular biology, diagnostic and potential therapeutic applications. A multi-gram-scale synthesis of the spermine phosphoramidite allowing several hundred coupling steps takes 2-3 weeks. Oligonucleotide synthesis and purification takes approximately 3 d. 相似文献
985.
Meunier B Dumas E Piec I Béchet D Hébraud M Hocquette JF 《Journal of proteome research》2007,6(1):358-366
986.
The essential role of Drosophila HIRA for de novo assembly of paternal chromatin at fertilization 下载免费PDF全文
In many animal species, the sperm DNA is packaged with male germ line–specific chromosomal proteins, including protamines. At fertilization, these non-histone proteins are removed from the decondensing sperm nucleus and replaced with maternally provided histones to form the DNA replication competent male pronucleus. By studying a point mutant allele of the Drosophila Hira gene, we previously showed that HIRA, a conserved replication-independent chromatin assembly factor, was essential for the assembly of paternal chromatin at fertilization. HIRA permits the specific assembly of nucleosomes containing the histone H3.3 variant on the decondensing male pronucleus. We report here the analysis of a new mutant allele of Drosophila Hira that was generated by homologous recombination. Surprisingly, phenotypic analysis of this loss of function allele revealed that the only essential function of HIRA is the assembly of paternal chromatin during male pronucleus formation. This HIRA-dependent assembly of H3.3 nucleosomes on paternal DNA does not require the histone chaperone ASF1. Moreover, analysis of this mutant established that protamines are correctly removed at fertilization in the absence of HIRA, thus demonstrating that protamine removal and histone deposition are two functionally distinct processes. Finally, we showed that H3.3 deposition is apparently not affected in Hira mutant embryos and adults, suggesting that different chromatin assembly machineries could deposit this histone variant. 相似文献
987.
Don-Marc Franchini Olivia Lanvin Marie Tosolini Emilie Patras de Campaigno Anne Cammas Sarah Péricart Clara-Maria Scarlata Morgane Lebras Cédric Rossi Laetitia Ligat Fréderic Pont Paola B. Arimondo Camille Laurent Maha Ayyoub Fabien Despas Maryse Lapeyre-Mestre Stefania Millevoi Jean-Jacques Fournié 《Cell reports》2019,26(1):94-107.e7
988.
Endoscopic imaging of the stomach is improving. In addition to narrow band imaging, other methods, for example, blue light imaging and linked color imaging, are now available and can be combined with artificial intelligence systems to obtain information on the gastric mucosa and detect early gastric cancer. Immunohistochemistry is only recommended as an ancillary stain in case of chronic active gastritis without Helicobacter pylori detection by standard staining, and recommendations to exclude false negative H. pylori results have been made. Molecular methods using real‐time PCR, droplet digital PCR, or amplification refractory mutation system PCR have shown a high accuracy, both for detecting H. pylori and for clarithromycin susceptibility testing, and can now be used in clinical practice for targeted therapy. The most reliable non‐invasive test remains the 13C‐urea breath test. Large data sets show that DOB values are higher in women and that the cut‐off for positivity could be decreased to 2.74 DOB. Stool antigen tests using monoclonal antibodies are widely used and may be a good alternative to UBT, particularly in countries with a high prevalence of H. pylori infection. Attempts to improve serology by looking at specific immunodominant antigens to distinguish current and past infection have been made. The interest of Gastropanel® which also tests pepsinogen levels was confirmed. 相似文献
989.
Charles Banliat Florine Dubuisson Emilie Corbin Julie Beurois Daniel Tomas Daniel Le Bourhis Pascal Salvetti Valrie Labas Pascal Mermillod Marie Saint‐Dizier 《Molecular reproduction and development》2019,86(6):661-672
The objective of this study was to evaluate the effect of progesterone (P4), estradiol (E2), and cortisol (CO) at intraoviductal concentrations on bovine embryo development and quality in vitro. After fertilization of in vitro matured oocytes, zygotes were cultured for 8 days in synthetic oviductal fluid, supplemented with 55 ng/ml P4, 120 pg/ml E2, 40 ng/ml CO, or their combination (ALL). Control embryos were cultured with vehicle (0.1% ethanol). Exposure to steroids did not affect the embryo developmental rate nor the mean number of cells per blastocyst. However, at 24 hr after vitrification‐warming, exposure to P4 improved the proportion of embryos that re‐expanded and were viable while exposure to CO decreased the proportion of viable embryos. By intact cell MALDI‐TOF mass spectrometry, a total of 242 phospholipid masses of 400–1000 m/z were detected from individual fresh blastocysts. Exposure to ALL induced the highest and most specific changes in embryo phospholipids, followed by P4, E2, and CO. In particular, the m/z 546.3 and 546.4 attributed to lysophosphatidylcholines were found less abundant after exposure to P4. In conclusion, exposure of bovine embryos to intraoviductal concentrations of steroid hormones did not affect in vitro development but changed blastocyst quality in terms of cryotolerance and phospholipid profiles. 相似文献
990.