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891.
Nucleus-targeted therapy holds great promise in cancer treatment; however, a lack of effective nucleus-specific delivery significantly limits its application potential. Here, we report a nucleus-targeted synergistic chemo-photodynamic therapy based on the self-assembly of chlorin e6 (Ce6) and doxorubicin (DOX) tuned by clickable dibenzocyclooctyne (DIBO) functionalized lysine (D-K) and subsequent reaction with crosslinkers. The assembled nanodrugs with high loading efficiency and long-term stability show enhanced cellular uptake and accumulation in the nucleus, resulting in greatly improved in vitro and in vivo chemo-photodynamic efficacy. Notably, D-K can promote the rapid self-assembly of Ce6 and DOX in aqueous solution, avoiding the introduction of organic solvents or tedious preparations. In addition, the introduction of the DIBO group can effectively expand the types of self-assembly material and enhance the self-assembly behaviour through a copper-free click reaction. Therefore, we present an effective nucleus-targeted combination drug delivery strategy, which has great potential in the treatment of many diseases.

A highly efficient nucleus-targeted multi-drug delivery nanoplatform based on clickable amino acid tuned self-assembly of chlorin e6 and doxorubicin has been prepared for enhanced photodynamic therapy and chemotherapy.  相似文献   
892.
This study concentrated on the production of molecularly imprinted polymers (MIPs) as highly selective sorbents for felodipine (FLD), a representive dihydropyridine calcium antagonists. Demonstrated chromatographically through a selection factor, these MIPs showed high selectivity for the template molecule among a group of structurally similar compounds. The recognition was found to correlate with structural similarity to the template compound.  相似文献   
893.
Lanthanum hexaboride nanowires produced by chemical vapor deposition are single-crystalline and grown along the [111] direction. Streaks appearing in the electron diffraction spots indicate the lateral direction perpendicular to the nanowire growth axis.  相似文献   
894.
Four new cholest-type steroidal glycosides, junceellosides A-D, isolated from the EtOH/CH(2)Cl(2) extracts of the South China Sea gorgonian coral Junceella juncea, were identified. Complete assignments of the (1)H and (13)C NMR chemical shifts for these compounds were achieved by means of one- and two-dimensional NMR techniques, including (1)H-(1)H COSY, HSQC, HMBC and NOESY spectra.  相似文献   
895.
In this study, we demonstrated that doping polymer matrix with a small amount of reduced graphene oxide (rGO) component (0.05–0.2%) had significant influence on the polymerisation kinetics and electro-optical performances of polymer-dispersed liquid crystal films (PDLCs) fabricated with macro reversible addition-fragmentation chain transfer agents. The effects of rGO content were studied in terms of morphology, compound viscosity, polymer conductivity, polymerisation kinetics and driving voltage of PDLCs. The results exhibited that higher rGO content increased the compound viscosity and the entire process proceeded slowly. Furthermore, the addition of rGO increased the polymer conductivity and local electric field, and reduced the saturation voltage as well as the threshold voltage from 27.3 to 19.5 V and 13.2 to 6.41 V, respectively.  相似文献   
896.
Bragg reflections of cholesteric liquid crystals at normal and oblique incidences were investigated using the finite element method (FEM). Detailed FEM derivations together with the consideration of boundary conditions are given. Two methods for achieving broadband Bragg reflection are analysed: one is to use high birefringence liquid crystal in the uniform pitch structure, the other is to use the gradient pitch structure. In each case, the number of cholesteric pitches required for establishing the Bragg reflection was simulated.  相似文献   
897.
本文以四氟对苯二甲酸(H2tfbdc)和2,2′-联吡啶(bpy)为配体,合成了2个锌(Ⅱ)的配合物[Zn2(bpy)4(Htfbdc)2(tfbdc)](1)and[Zn(bpy)(H2O)2(tfbdc)](2)。并用元素分析、红外光谱、X-射线单晶衍射结构分析、热重分析等对其进行了表征。化合物1和2均属于三斜晶系,空间群为P1。配合物1和2中的锌(Ⅱ)离子分别位于畸变的八面体和畸变的三角双锥构型中。配合物1为双核结构,它们通过分子间氢键进一步形成一个二维的结构;配合物2是一个单核的两性离子,两性离子间通过氢键形成一个三维的空间网状超分子结构。考察了两种配合物的固体荧光性质。  相似文献   
898.
The interaction between bovine serum albumin (BSA) and FeIII complexes with three binary organic acid (biorga) ligands, [FeIII(oxa)(H2O)4]+ (oxa = oxalic acid), [FeIII(pra)(H2O)4]+ (pra = propanedioic acid) and [FeIII(sua)(H2O)4]+ (sua = succinic acid), as well as the sonocatalytic damage of BSA in the presence of these three FeIII–biorga complexes under ultrasonic irradiation, were studied by UV–vis and fluorescence spectra. The experimental results show that the fluorescence quenching process of BSA caused by three FeIII–biorga complexes are all static quenching and the corresponding quenching rate constants (K q), equilibrium constants (K A) and the binding site numbers (n) were calculated. The results reveal that, under ultrasonic irradiation, the BSA molecules were obviously damaged by these FeIII–biorga complexes. In addition, the effects of several factors on the damage of BSA molecules were examined. The experimental results demonstrate that the damage degree of BSA increased with an increase of ultrasonic irradiation time, FeIII–biorga complex concentration, and ionic strength. In comparison, [FeIII(pra)(H2O)4]+ exhibited higher sonocatalytic activity than [FeIII(oxa)(H2O)4]+ and [FeIII(sua)(H2O)4]+. Finally, the extent of generation of $ \cdot {\text{O}}_{2}^{ - } $ · O 2 ? and ·OH during sonocatalytic processes was estimated. Perhaps, the results will be significant for promoting sonodynamic treatment (SDT) of tumors at the molecular level.  相似文献   
899.
Pseudo-first order reaction rate constants of 5,10,15-tris(pentafluorophenyl)corrole Mn(V)-oxo (F15CMn(V)-oxo),5,15-bis(pentafluorophenyl)-10-(phenyl)corrole Mn(V)-oxo(F10CMn(V)-oxo),5,15- bis(phenyl)-10-(pentafluorophenyl)corrole Mn(V)-oxo(F5CMn(V)-oxo) and 5,10,15-tris(phenyl)corrole Mn(V)-oxo(F0CMn(V)-oxo) with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn(V)-oxo corrole and alkene is solvent-dependent.  相似文献   
900.
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