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221.
Ujjinamatada RK Agasimundin YS Zhang P Hosmane RS Schuessler R Borowski P Kalicharran K Fattom A 《Nucleosides, nucleotides & nucleic acids》2005,24(10-12):1775-1788
The attempted synthesis of a ring-expanded guanosine (1) containing the imidazo[4,5-e][1,3]diazepine ring system by condensation of 1-(2'-deoxy-beta-D-erythropentofuranosyl)-4-ethoxycarbonylimidazole-5-carbaldehyde (2) with guanidine resulted in the formation of an unexpected product, 1-(2'-deoxy-beta-D-erythropentofuranosyl)-5-(2, 4-diamino-3, 6-dihydro-1,3, 5-triazin-6-yl)imidazole-4-carboxamide (7). The structure as well as the pathway of formation of 7 was corroborated by isolation of the intermediate, followed by its conversion to the product. Nucleoside 7 showed promising in vitro anti-helicase activity against the West Nile virus NTPase/helicase with an IC50 of 3-10 microg/mL. 相似文献
222.
In order to investigate the functional roles of a phytopathogenic fungal lectin (SRL) isolated from the bodies of Sclerotium rolfsii, the binding properties of SRL were studied by enzyme linked lectinosorbent assay and by inhibition of SRL-glycan interaction. Among glycoproteins (gp) tested for binding, SRL reacted strongly with GalNAc alpha1-->4Ser/Thr (Tn) and/or Gal beta1-->3GalNAc alpha1-->(T(alpha)) containing gps: human T(alpha) and Tn glycophorin, asialo salivary gps, and asialofetuin, but its reactivity toward sialylated glycoproteins was reduced significantly. Of the sugar ligands tested for inhibition of SRL-asialofetuin binding, Thomsen-Friedenreich residue (T(alpha)) was the best, being 22.4 and 2.24 x 10(3) more active than GalNAc and Gal beta1--> residues, respectively. Other ligands tested were inactive. When the glycans used as inhibitors, T(alpha), and/or Tn containing gps, especially asialo PSM, asialo BSM, asialo OSM, active antifreeze gp, asialo glycophorin and Tn-glycophorin were very active, and 1.0 x 10(4) times more potent than GalNAc. From these results, it is clear that the combining site of SRL should be of a cavity type and recognizes only Tn and T(alpha) residues of glycans; it is suggested that T(alpha) and Tn glycotopes, which are present only in abnormal carbohydrate sequences of higher orders of mammal, are the most likely sites for phytopathogenic fungal attachment as an initial step of infection. The affinity of SRL for ligands can be ranked in decreasing order as follows: multivalent T(alpha) and Tn > monomeric T(alpha) and Tn > GalNAc > II (Gal beta1-->4GlcNAc), L (Gal beta1-->4Glc), and Gal. 相似文献
223.
The temperature-composition phase diagram was derived for hydrated, binary mixtures of N-myristoyldimyristoylphosphatidylethanolamine (N-14 DMPE) and dimyristoylphosphatidylcholine by high sensitivity differential scanning calorimetry. Gel phase immiscibility was detected in mixtures containing up to 20 mol% N-14 DMPE and there was no evidence for compound formation between the two components. In the fluid phase nearly complete miscibility is indicated by the calorimetric data. These results are relevant to understanding the role of N-acylphosphatidylethanolamines in the stress combating responses of organisms and in their application to developing liposome-based drug delivery systems. 相似文献
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225.
Sheeba V Nihal M Mathew SJ Swamy NM Chandrashekaran MK Joshi A Sharma VK 《Chronobiology international》2001,18(4):601-612
The eclosion rhythm of a laboratory population of Drosophila melanogaster was studied under 12h light, 12h dark (LD 12:12) cycles. Although most of the flies were found to eclose just after “lights on” in LD 12:12, termed within gate (WG) flies, a few flies were found to eclose nearly 10h after peak eclosion, termed outside gate (OG) flies. The circadian parameters of the clocks controlling oviposition rhythms in the WG and the OG flies were estimated to understand the cause of such differences in the timing of eclosion. The distribution of the fraction of individual flies exhibiting single, multiple, and no significant period in the WG flies was significantly different from distribution in the OG flies. Compared to the WG flies, more OG flies were found to exhibit oviposition rhythm with multiple periodicity, whereas more WG flies exhibited an oviposition rhythm with a single significant period. The fraction of flies with arrhythmic oviposition was similar in both the WG and the OG flies. Free-running period τ in constant darkness (DD) and the phase angle difference ψ in LD 12:12 for the oviposition rhythm of WG and OG flies were significantly different. These results suggest that the differences in the time of eclosion between the flies eclosing within the gate and outside the gate of eclosion are probably due to differences in the circadian system controlling eclosion, which is reflected by the differences in their oviposition rhythm. (Chronobiology International, 18(4), 601-612, 2001) 相似文献
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227.
Photosynthetica - Three-year-old plants of Parthenium argentatum Gray cv. 11591 grown under natural photoperiod were exposed for 60 d to low night temperature (LNT) of 15 °C (daily from 18:00... 相似文献
228.
Srinivas Sulugodu Ramachandra Ritu Rana Singhal Reetika K. D. Jithendra 《Cell and tissue banking》2014,15(3):297-305
As esthetics gain importance, periodontal plastic surgical procedures involving soft tissue grafts are becoming commoner both around natural teeth as well as around implants. Periodontal soft tissue grafts are primarily used for the purpose of root coverage and in pre-prosthetic surgery to thicken a gingival site or to improve the crestal volume. Soft tissue grafts are usually harvested from the palate. Periodontal plastic surgical procedures involving soft tissue grafts harvested from the palate have two surgical sites; a recipient site and another donor site. Many patients are apprehensive about the soft tissue graft procedures, especially the creation of the second/donor surgical site in the palate. In the past decade, newer techniques and products have emerged which provide an option for the periodontist/patient to avoid the second surgical site. MucoMatrixX, Alloderm®, Platelet rich fibrin, Puros® Dermis and Mucograft® are the various options available to the practicing periodontist to avoid the second surgical site. Use of these soft tissue allografts in an apprehensive patient would decrease patient morbidity and increase patient’s acceptance towards periodontal plastic surgical procedures. 相似文献
229.
Devram Sampat Ghorpade Sahana Holla Srini V. Kaveri Jagadeesh Bayry Shripad A. Patil Kithiganahalli Narayanaswamy Balaji 《Molecular and cellular biology》2013,33(3):543-556
Hedgehog (HH) signaling is a significant regulator of cell fate decisions during embryogenesis, development, and perpetuation of various disease conditions. Testing whether pathogen-specific HH signaling promotes unique innate recognition of intracellular bacteria, we demonstrate that among diverse Gram-positive or Gram-negative microbes, Mycobacterium bovis BCG, a vaccine strain, elicits a robust activation of Sonic HH (SHH) signaling in macrophages. Interestingly, sustained tumor necrosis factor alpha (TNF-α) secretion by macrophages was essential for robust SHH activation, as TNF-α−/− macrophages exhibited compromised ability to activate SHH signaling. Neutralization of TNF-α or blockade of TNF-α receptor signaling significantly reduced the infection-induced SHH signaling activation both in vitro and in vivo. Intriguingly, activated SHH signaling downregulated M. bovis BCG-mediated Toll-like receptor 2 (TLR2) signaling events to regulate a battery of genes associated with divergent functions of M1/M2 macrophages. Genome-wide expression profiling as well as conventional gain-of-function or loss-of-function analysis showed that SHH signaling-responsive microRNA 31 (miR-31) and miR-150 target MyD88, an adaptor protein of TLR2 signaling, thus leading to suppression of TLR2 responses. SHH signaling signatures could be detected in vivo in tuberculosis patients and M. bovis BCG-challenged mice. Collectively, these investigations identify SHH signaling to be what we believe is one of the significant regulators of host-pathogen interactions. 相似文献
230.