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991.
We report here the synthesis, characterization and in vitro antiamoebic activity of 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones (TSC), 1–5, and their bidentate complexes [Ru(η4-C8H12)(TSC)Cl2] 1a–5a. The biological studies of these compounds were investigated against HK-9 strain of Entamoeba histolytica and the concentration causing 50% cell growth inhibition (IC50) was calculated in the micromolar range. The ligands exhibited antiamoebic activity in the range (2.05–5.29 μM). Screening results indicated that the potencies of the compounds increased by the incorporation of ruthenium(II) in the thiosemicarbazones. The complexes 1a–5a showed antiamoebic activity with an IC50 of 0.61–1.43 μM and were better inhibitors of growth of E. histolytica, based on IC50 values. The most promising among them is Ru(II) complex 2a having 1,2,3,4-tetrahydroquinoline as N4 substitution. 相似文献
992.
The reaction of the title complex with DNA has been examined. Addition of [(bpy)2(OH2)RuORu(OH2) (bpy)2]4+ to DNA leads to the reduction of the complex to Ru(bpy)2(OH2)22+, as indicated by absorption spectroscopy and cyclic voltammetry. The reaction is accelerated by Mg2+. The combined evidence points to a mechanism where the oxo-bridged dimer is hydrolyzed to a monomeric Ru(III) complex that is capable of oxidizing DNA to effect strand scission. Gel electrophoresis demonstrates nicking of supercoiled /gfX174 DNA by [(bpy)2(OH2)RuORu(OH2) (bpy)2]4+, and double-stranded cleavage is observed in the presence of Mg2+. Linearization of the plasmid prior to treatment with the complex does not lead to further fragmentation, suggesting that supercoiling is required to realize double-stranded cleavage. 相似文献
993.
Esperanza Fernández Mark O Collins Rachel T Uren Maksym V Kopanitsa Noboru H Komiyama Mike D R Croning Lysimachos Zografos J Douglas Armstrong Jyoti S Choudhary Seth G N Grant 《Molecular systems biology》2009,5(1)
The molecular complexity of mammalian proteomes demands new methods for mapping the organization of multiprotein complexes. Here, we combine mouse genetics and proteomics to characterize synapse protein complexes and interaction networks. New tandem affinity purification (TAP) tags were fused to the carboxyl terminus of PSD‐95 using gene targeting in mice. Homozygous mice showed no detectable abnormalities in PSD‐95 expression, subcellular localization or synaptic electrophysiological function. Analysis of multiprotein complexes purified under native conditions by mass spectrometry defined known and new interactors: 118 proteins comprising crucial functional components of synapses, including glutamate receptors, K+ channels, scaffolding and signaling proteins, were recovered. Network clustering of protein interactions generated five connected clusters, with two clusters containing all the major ionotropic glutamate receptors and one cluster with voltage‐dependent K+ channels. Annotation of clusters with human disease associations revealed that multiple disorders map to the network, with a significant correlation of schizophrenia within the glutamate receptor clusters. This targeted TAP tagging strategy is generally applicable to mammalian proteomics and systems biology approaches to disease. 相似文献
994.
Summary Copper(II) complexes CuL1L2 with the ligand pairs 3-phosphoglycerate (PG)/ethylenediamine (en), phosphoserine (PS)/ethylenediamine, phosphoserine/malonate (mal) are shown to be effective in inducing the release of both iron atoms from di-ferric transferrin (Fe2Tf; human serum transferrin) at pH 7.3 in 1 M NaCl at 25°C. Half-times of the reaction with Cu(PG)(en)– were less than 1 min at 0.02 M concentration. The iron(III) products are polynuclear hydroxo complexes. There is weaker interaction with Cu(PS)
2
4–
and virtually none with Cu(serine)(en) nor Cu(PS)(2,2-bipyridyl)–, revealing crucial effects of the combined ligand sphere including the phosphomonoester group. The results suggest that the release of iron from Fe2Tf, or from either monoferric transferrins, occurred due to the breakdown of the stability of iron binding in conjunction with the expulsion of the synergistic anion carbonate (or oxalate). The active copper(II) complexes are postulated to be models of membrane components that could liberate iron from transferrin succeeding its uptake at the receptor sites of cells.Abbreviations PG
phosphoglycerate
- PS
phosphoserine
- en
ethylenediamine
- Fe2Tf
diferric transferrin
- FecTf and FeNTf
transferrin with iron bound to the lobe containing the C- or N-terminus, respectively
- apoTf
apotransferrin
- K-3
all-cis-1,3,5-tris(trimethylammonio)-2,4,6-cyclo-hexanetriol
- NTA
nitrilotriacetic acid; bipy, 2,2-bipyridine; mal, malonate 相似文献
995.
查阅国内外文献,采用整理归纳、引用和分析的方法,概述了鼻黏膜免疫载体材料脂质体、免疫刺激复合物和壳聚糖的生物学特性及其在气溶胶疫苗领域的应用。脂质体、免疫刺激复合物和壳聚糖作为气溶胶疫苗鼻黏膜免疫的载体,能够增强疫苗的免疫原性,提高机体的体液免疫和细胞免疫水平,因此,可作为疫苗抗原激发特异免疫应答的生物材料。 相似文献
996.
Reactions of RhCl(cod)(THP) (cod = 1,5-cyclooctadiene; THP = P(CH2OH)3) with PMePh2 or PCyPh2 (Cy = cyclohexyl) in acetone/MeOH solution under H2 surprisingly form the complexes cis, mer-Rh(H)2Cl(PRPh2)3 (R = Me or Cy); both complexes are characterized by crystallography (the first structures in which the hydride ligands of such dihydrido-chloro-trisphosphine complexes have been located), and by detailed 1H and 31P NMR spectroscopy. The key role of the THP in the observed chemistry is discussed. 相似文献
997.
Jonas Krber Itka Bkouche-Waksman Claudine Pascard Martina Thomann Olivier Kahn 《Inorganica chimica acta》1995,230(1-2):159-163
ZnCl2 reacts with 1,2,4-1H-triazole to afford Zn(trz)Cl. A spontaneous deprotonation of Htrz occurs. The crystal structure of Zn(trz)Cl has been solved. The compound crystallizes in the space group P21/n. The lattice parameters are a = 8.863(4), B = 9.762(4), C = 6.146(3) Å, β = 99.56(10)°, with Z = 4. The 1,2,4-triazolato bridges three zinc atoms through its three nitrogen atoms, affording a layered structure. The zinc atom is in an N3Cl tetrahedral coordination. The layers are not planar, but rather corrugated. The chlorine atoms point to either side of the layers, and play the role of spacers. The shortest interlayer ZnZn separation is 5.701 Å. 相似文献
998.
Ekkehard Lindner Walter Wassing Markus W. Pitsch Riad Fawzi Manfred Steimann 《Inorganica chimica acta》1994,220(1-2):107-113
The reaction of the bis(triflates) 1,2-bis[2-(trifluoromethylsulfonyloxy)ethyl]benzene (1), 1,2-bis[3-(trifluoromethylsulfonyloxy)propyl]benzene (3) and 1,2-bis{2-[2-(trifluoromethylsulfonyloxy)ethyl]phenyl}ethane (6), respectively, with the carbonyl metalates [M(CO)4]2- (M=Os (a), Ru (b), Fe (c)) results in the formation of the osmaorthocyclophanes 2a, 4a, 7a and 8a, the ruthenacylophane 2b and the ferracyclophanes 2c and 7c, respectively. Carbon monoxide insertion into the Fe-Cσ bonds of the ferracycles 2c and 7c, respectively, affords the ketones 3-oxo[5]orthocyclophane (9) and 3-oxo[5.2]orthocyclophane (11). The structure of 2a was investigated by an X-ray structural analysis. 2a crystallizes in the monoclinic space group P21/n with Z=4. 相似文献
999.
Near-infrared absorption spectra of A2CoX4 (A = Cs, ethyl4N; X = Cl, Br) single crystals and from KBr pellets at low temperature are recorded by the Fourier transform technique. At 2 K a rich fine structure of v1(4A2→4T2) and v2(4A2→4T1) ligand field spectra is detected which can be assigned to low symmetry level splittings due to actual site symmetries superimposed by vibrational fine structure. Comparison of fundamental frequencies obtained from far-infrared spectra allows an assignment of all peaks measured in the vibronic spectra to vibrational modes of the MX4 complex. Zero-phonon bands are identified using the assistance of angular overlap calculations. 相似文献
1000.
Guibin Ma Andrey Ilyukhin Julius Glaser Imre Tth Lszl Zkny 《Inorganica chimica acta》2001,320(1-2):92-100
The formation of three [Tl(en)n]3+ complexes (n=1–3) in a pyridine solvent has been established by means of 205Tl and 1H NMR. Their stepwise stability constants based on concentrations, Kn=[Tl(en)n 3+]/{[Tl(en)n−1 3+]·[en]}, at 298 K in 0.5 M NaClO4 ionic medium in pyridine, were calculated from 205Tl NMR integrals: log K1=7.6±0.7; log K2=5.2±0.5 and log K3=2.64±0.05. Linear correlation between both the 205Tl NMR shifts and spin–spin coupling 205Tl–1H versus the stability constants has been found and discussed. A single crystal with the composition [Tl(en)3](ClO4)3 was synthesized and its structure determined by X-ray diffraction. The Tl3+ ion is coordinated by three ethylenediamine ligands via six N-donor atoms in a distorted octahedral fashion. 相似文献