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991.
Homocystinuria is a metabolic disorder caused by a deficiency of cystathionine beta-synthase (CBS). The major clinical symptoms of this disease are mental retardation, lens dislocation, vascular disease with life-threatening thromboembolisms, and skeletal deformities. The major treatments for CBS deficiency include pharmacologic doses of pyridoxine or dietary restriction of methionine. There is currently no effective long-term treatment to lower the elevated plasma levels of homocysteine. However, gene therapy could be an effective novel approach for the treatment of homocystinuria. A recombinant adeno- associated virus vector carrying human CBS cDNA (rAAV-hCBS) was constructed and administered to CBS-/- mice by intramuscular (IM) and intraperitoneal (IP) injections. Serum homocysteine concentrations significantly decreased in treated mice compared with age-matched controls two weeks after treatment. The treated CBS-/- mice had life spans 3-7 days longer compared with untreated CBS-/- mice. In CBS-/- mice treated with rAAV-hCBS via IP injection, the vector was detected in all organs examined including liver, spleen, and kidney, and CBS gene expression was observed by immunohistochemical staining in the liver. These results indicate the efficacy of gene delivery and demonstrate the possibility of gene therapy mediated by AAV gene transfer in this mouse model of homocystinuria. 相似文献
992.
Ang CY Boeré RT Goh LY Koh LL Kuan SL Tan GK Yu X 《Chemical communications (Cambridge, England)》2006,(45):4735-4737
The title heterocyclic radicals coordinate to either 17e CpCr(CO)3 or 15e CpCr(CO)2 moieties as one-electron or as three-electron donors, respectively; in the former the bonding is via the perpendicular p orbital of the sulfur atom, while in the latter bonding is via p(pi) orbitals on both sulfur and nitrogen. 相似文献
993.
CD43 (sialophorin, leukosialin) is a heavily sialylated surface protein expressed on most leukocytes and platelets including T cells. Although CD43 antigen is known to have multiple and complex structure, exact function of CD43 in each cell type is not completely understood. Here we evaluated the role of CD43 in Fas (CD95)-induced cell death in human T lymphoblastoid cell line, Jurkat. Crosslinking CD43 antigen by K06 mAb increased the Fas-mediated Jurkat cell apoptosis and the augmentation was inhibited by treatment with caspase inhibitors. Further, CD43 signaling of Jurkat cells induced Fas oligomerization on the cell surfaces implying that CD43 ligation have effects on early stage of Fas-induced T cell death. These also suggest that CD43 might play an important role in contraction of the immune response by promotion of Fas-induced apoptosis in human T cells. 相似文献
994.
Jung K Richter J Kabrodt K Lücke IM Schellenberg I Herrling T 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(4):846-850
In the last decade, naturally occurring antioxidants continue to play an important role in the food-supplement industry. The content of antioxidants in a plant depends on the species, temperature, humidity, period of growth, harvest month, part of the plant used and many other variables. Herein, we present a new method able to determine the all over antioxidative power (AP) of plant extracts or lyophilised plant parts based on the reducing activity against a stable test radical. The method is performed by ESR spectroscopy and is based on the well-known 1,1-diphenyl-2-picryl-hydrazil (DPPH) method with the major difference that both the antioxidative capacity and the antioxidative activity are used to characterise an antioxidant. The resulting antioxidative power is expressed in antioxidative units (AU), where 1AU corresponds to the activity of a 1 ppm solution of Vitamin C as a benchmark. This method allows a rapid, unexpensive and general applicable technique for the measurement of the antioxidative power of very different kinds of substances. The inclusion of the kinetic behaviour of the reducing process of the antioxidant for the determination of the AP allows the identification of the main antioxidant present in a sample. Herein, we present the application example of seeds, sprouts and adult parts of dandelion, amaranth, quinoa, fenugreek, broccoli, red clover and mugwort, where the AP method permits to characterise the plants with the highest antioxidant capacity and reaction velocity. The method permits to select active plant extracts for the food and nutrition industry. 相似文献
995.
One known and two new glycerolipids have been isolated from a Sarcotragus sp. marine sponge. The gross structures were established based on NMR and MS analysis. 相似文献
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The band artifact in steady-state free precession can be reduced by synthesizing the multiple images obtained through different phase increments of successive radiofrequency pulses. Even though the complex summation method was reported to be effective in reducing the band artifact, it has the pitfalls of intensity abnormality and sensitivity to the phase abnormality. Two new methods have been developed for more reliable reduction of the band artifact than the complex summation method. One method is to sum the complex images partially and to take the maximum intensity of the partially summed images. The other method is to sum the free induction decay (FID) and primary echo components of the Fourier series that are obtained through Fourier analysis of the complex base images. Both proposed methods were compared with other magnitude (maximum intensity projection, spectrally decomposed synthesis, sum-of-squares, nonlinear averaging) and complex-based (complex summation, magnitude-weighted complex summation) methods experimentally at 3 T for the phantom and volunteer's head imaging. Both proposed methods were confirmed to maintain the advantage of the complex summation in reducing both the dark and bright band artifacts while reducing the intensity abnormality and sensitivity to the phase abnormality from that of the complex summation method over a wide range of flip angles and relaxation times. 相似文献
1000.
Tae Hee Kim Jai Keun Kim Wooyoung Shim Sun Yong Kim Tae Jun Park Jae Yeon Jung 《Magnetic resonance imaging》2010
In vivo visualization of transplanted stem cells with noninvasive technique is essential for the monitoring of cell implantation, homing and differentiation. At present, superparamagnetic iron oxide (SPIO) is most commonly used for cell labeling. However, stem cells lack phagocytic capacity and transfection agent is required for sufficient internalization of SPIO for cellular imaging. However, the potential hazards of transfection agents are not fully investigated. Instead of SPIO, we used commercially available new tagging material, fluorescent magnetic nanoparticle (MNP) containing rhodamine B isothiocyanate within a silica shell (Biterials, Seoul, Korea). This tagging material does not require transfection agents for the cell labeling. In addition to that, the core of this MNP is composed of ferrite and the inner portion of silica shell contains fluorescent materials, therefore, it has both magnetic and optical features. This study was designed to track intrasplenically injected bone marrow mesenchymal stem cells (MSCs) labeled with fluorescent MNP in liver cirrhosis rat model with 3-T magnetic resonance equipment. We compared magnetic resonance imaging (MRI) of livers in rats which were injected with non-labeled stem cells or labeled stem cells with MNP or SPIO. We found that the respective liver-to-muscle contrast-to-noise ratios at 3 and 5 h after MNP or SPIO-labeled stem cell injection was significantly lower than that of pre-injection and non-labeled group. There was no significant difference between MNP-labeled group and SPIO-labeled group. We can effectively detect intrasplenically injected MNP-labeled MSCs in an experimental rat model of liver cirrhosis with 3-T MRI. 相似文献