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121.
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Rostislav A. Petrov Svetlana Yu. Maklakova Yan A. Ivanenkov Stanislav A. Petrov Olga V. Sergeeva Emil Yu. Yamansarov Irina V. Saltykova Igor I. Kireev Irina B. Alieva Ekaterina V. Deyneka Alina A. Sofronova Anastasiia V. Aladinskaia Alexandre V. Trofimenko Renat S. Yamidanov Sergey V. Kovalev Victor E. Kotelianski Timofey S. Zatsepin Elena K. Beloglazkina Alexander G. Majouga 《Bioorganic & medicinal chemistry letters》2018,28(3):382-387
Asialoglycoprotein receptor (ASGP-R) is a promising biological target for drug delivery into hepatoma cells. Nevertheless, there are only few examples of small-molecule conjugates of ASGP-R selective ligand equipped by a therapeutic agent for the treatment of hepatocellular carcinoma (HCC). In the present work, we describe a convenient and versatile synthetic approach to novel mono- and multivalent drug-conjugates containing N-acetyl-2-deoxy-2-aminogalactopyranose and anticancer drug – paclitaxel (PTX). Several molecules have demonstrated high affinity towards ASGP-R and good stability under physiological conditions, significant in vitro anticancer activity comparable to PTX, as well as good internalization via ASGP-R-mediated endocytosis. Therefore, the conjugates with the highest potency can be regarded as a promising therapeutic option against HCC. 相似文献
123.
Controlling the near‐infrared transparency of costal cartilage by impregnation with clearing agents and magnetite nanoparticles 下载免费PDF全文
Yulia Alexandrovskaya Kirill Sadovnikov Andrey Sharov Anna Sherstneva Evgeniy Evtushenko Alexander Omelchenko Mariya Obrezkova Valery Tuchin Valery Lunin Emil Sobol 《Journal of biophotonics》2018,11(2)
Penetration depth of near‐infrared laser radiation to costal cartilage is controlled by the tissue absorption and scattering, and it is the critical parameter to provide the relaxation of mechanical stress throughout the whole thickness of cartilage implant. To enhance the penetration for the laser radiation on 1.56 μm, the optical clearing solutions of glycerol and fructose of various concentrations are tested. The effective and reversible tissue clearance was achieved. However, the increasing absorption of radiation should be concerned: 5°C‐8°C increase of tissue temperature was detected. Laser parameters used for stress relaxation in cartilage should be optimized when applying optical clearing agents. To concentrate the absorption in the superficial tissue layers, magnetite nanoparticle (NP) dispersions with the mean size 95 ± 5 nm and concentration 3.9 ± 1.1 × 1011 particles/mL are applied. The significant increase in the tissue heating rate was observed along with the decrease in its transparency. Using NPs the respective laser power can be decreased, allowing us to obtain the working temperature locally with reduced thermal effect on the surrounding tissue. 相似文献
124.
Prospective Studies Exploring the Possible Impact of an ID3 Polymorphism on Changes in Obesity Measures 下载免费PDF全文
125.
Jamille Karina Coelho Correa Emil José Hernández-Ruz Marcos Tobias de Santana Miglionico Lúcio André Viana 《Systematic parasitology》2018,95(2-3):319-324
A new coccidian species of the genus Isospora Schneider 1881 (Apicomplexa, Eimeriidae) is reported from a single specimen of chelid turtle, Platemys platycephala (Schneider, 1792), obtained in a flooded area of the Amazonian municipality of Altamira, in Pará State, northern Brazil. The oöcysts of Isospora platemysi n. sp. are subspheroidal, 19.0–24.0 × 22.5–18.5 (22.6 × 20.8) µm in size [length/width ratio 1.0–1.1 (1.1)], with a colourless wall, 1.0–1.9 (1.4) wide, with two smooth layers; polar granule is present, oöcyst residuum and micropyle are both absent. The sporocyst is ovoidal, 10.0–12.1 × 8.0–10.0 (11.0 × 9.1) µm [length/width ratio 1.1–1.3 (1.2), with a knob-like Stieda body. Sub-Stieda body is present, rounded irregular-trapezoidal; para-Stieda body is absent. Sporocyst residuum is dispersed and composed of granules of differing sizes. This is only the fifth record of Isospora in chelonians, and the first report of a coccidian parasite of the genus Platemys. 相似文献
126.
The rate of reaction of [Cr(III)Y]aq (Y is EDTA anion) with hydrogen peroxide was studied in aqueous nitrate media [μ = 0.10 M (KNO3)] at various temperatures. The general rate equation, Rate = [Cr(III)Y]aq[H2O2] holds over the pH range 5–9. The decomposition reaction of H2O2 is believed to proceed via two pathways where both the aquo and hydroxo-quinquedentate EDTA complexes are acting as the catalyst centres. Substitution-controlled mechanisms are suggested and the values of the second-order rate constants k1 and k2 were found to be 1.75 × 10?2 M?1 s?1 and 0.174 M?1 s?1 at 303 K respectively, where k2 is the rate constant for the aquo species and k2 is that for the hydroxo complex. The respective activation enthalpies (ΔH*1 = 58.9 and ΔH*2 = 66.5 KJ mol?1) and activation entropies (ΔS*1 = ?85 and ΔS*2 = ?40 J mol?1 deg?1) were calculated from a least-squares fit to the Eyring plot. The ionisation constant pK1, was inferred from the kinetic data at 303 K to be 7.22. Beyond pH 9, the reaction is markedly retarded and ceases completely at pH ? 11. This inhibition was attributed in part to the continuous loss of the catalyst as a result of the simultaneous oxidation of Cr(III) to Cr(VI). 相似文献
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Two techniques suitable for qualitative radioautographic analysis of histologic sections of human testicular tissue are described. In one, deparaffinized wet slides are coated with photographic emulsion resulting in significant improvement in preservation of histologic quality of the tissue section. In the second procedure stained and processed slides are coated with a thin layer of H.S.R. prior to coating with photographic emulsion. This procedure allows excellent preservation of the stained tissue section and also enables visualization of the reactive cell and its radioautographic image at two different focal planes. The techniques can be applied with equal advantage to histologic preparations of other tissues. 相似文献
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The relation between visual acuity and illumination was measured in red and blue light, using a broken circle or C and a grating as test objects. The red light data fall on single continuous curves representing pure cone vision. The blue light data fall on two distinct curves with a transition at about 0.03 photons. Values below this intensity represent pure rod vision. Those immediately above represent the cooperative activity of rods and cones, and yield higher visual acuities than either. Pure cone vision in this intensity region is given by central fixation (C test object). All the rest of the values above this transition region represent pure cone vision. In blue light the rod data with the C lie about 1.5 log units lower on the intensity axis (cone scale) than they do in white light, while with the grating they lie about 1.0 log unit lower than in white light. Both the pure rod and cone data with the C test object are precisely described by one form of the stationary state equation. With the grating test object and a non-limiting pupil, the pure rod and cone data are described by another form of the same equation in which the curve is half as steep. The introduction of a small pupil, which limits maximum visual acuity, makes the relation between visual acuity and illumination appear steeper. Determinations of maximum visual acuities under a variety of conditions show that for the grating the pupil has to be larger, the longer the wavelength of the light, in order for the pupil not to be the limiting factor. Similar measurements with the C show that when intensity discrimination at the retina is experimentally made the limiting factor in resolution, visual acuity is improved by conditions designed to increase image contrast. However, intensity discrimination cannot be the limiting factor for the ordinary test object resolution because the conditions designed to improve image contrast do not improve maximum visual acuity, while those which reduce image contrast do not produce proportional reductions of visual acuity. 相似文献