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991.
992.
A giant aneurysm of the right common iliac artery presenting with an arteriovenous fistula (AVF) between the iliac artery and iliac vein and deep venous thrombosis of the right lower extremity is reported. The clinical signs and the radiologic and surgical management of the condition are discussed. In addition a brief review of the literature is given. 相似文献
993.
In the first 100 patients operated on for C T-E PH, three were referred with the diagnosis of UPAA having been made elsewhere. We found that many features of these two conditions are so similar that differential diagnosis is very difficult. Shared features may include findings on chest x-ray film, pulmonary angiography, CT scan and MRI studies. Since the two conditions vary substantially with respect to the methods of potential surgical correction, recognition of this possible differential diagnostic dilemma is important. 相似文献
994.
Chemiluminescence from Acetaldehyde Oxidation by Xanthine Oxidase Involves Generation of and Interactions with Hydroxyl Radicals 总被引:2,自引:0,他引:2
Susana Puntarulo Arthur I. Cederbaum 《Alcoholism, clinical and experimental research》1989,13(1):84-90
The ability of acetaldehyde to generate free radicals is often ascribed to its oxidation by xanthine oxidase, with the subsequent production of reactive oxygen intermediates. Chemiluminescence associated with the oxidation of acetaldehyde by xanthine oxidase was inhibited by superoxide dismutase, catalase, or several hydroxyl radical scavenging agents, and was stimulated by the addition of EDTA or ferric-EDTA. This suggests that the light emission is primarily due to the production of hydroxyl radicals via an iron-catalyzed Haber-Weiss type of reaction. Chemiluminescence with hypoxanthine as substrate for xanthine oxidase was much lower than that found with acetaldehyde, yet rates of hydroxyl radical production were greater with hypoxanthine. Acetaldehyde increased light emission in the presence of hypoxanthine by a greater than additive effect. These results suggest a complex role for acetaldehyde in catalyzing xanthine oxidase-dependent chemiluminescence. It appears that besides being a substrate for xanthine oxidase, acetaldehyde also reacts with the generated hydroxyl radical to produce acetaldehyde radicals, which yield chemiluminescence upon their decay. Further studies will be required to evaluate whether the production of such species contributes to or plays a role in the generation of reactive oxygen intermediates and toxicity associated with acetaldehyde metabolism. 相似文献
995.
Breast preserving surgery or conservative surgery consists at present of a combination of a reduced operation--tumorectomy or wedge resection or subcutaneous mastectomy--with adequate radiotherapy whereby a doses of 40-50 Gy is used with or without an additional booster dose of 10 Gy. Recent studies of 5-year- and 10-year-survival rates after conservative management have been shown to be identical with radical operations (Rotter-Halsted, Patey-Auchincloss). In the Departments of Gynecology and Obstetrics of the Universities of Münster and Rostock the partial bilateral subcutaneous mastectomy with lymphadenectomy and irradiation is the preferred method of conservative management for breast cancer. Indications and technique are discussed. 相似文献
996.
K M Klueber 《The Anatomical record》1987,219(4):370-3, 429-33
Although the reinnervation of muscle grafts has been demonstrated, the question remains as to the source of neurons reinnervating the graft. A muscle graft could be reinnervated by its original neurons (neural neurotization) or by sprouting of axons which supply the intact myofibers of surrounding muscles (muscle neurotization). The objective of this study was to evaluate the role of muscle neurotization in the reinnervation process using both horseradish peroxidase and fluorescent tracers. Observations from 20 muscle grafts indicate that the neurons reinnervating the grafts are from the original motor neuron pool. Thus muscle neurotization may not occur during the reinnervation process. 相似文献
997.
Fate of micelles and quantum dots in cells. 总被引:2,自引:0,他引:2
Dusica Maysinger Jasmina Lovri? Adi Eisenberg Radoslav Savi? 《European journal of pharmaceutics and biopharmaceutics》2007,65(3):270-281
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles. 相似文献
998.
Pascale Jolliet Stéphane Nion Gwena?lle Allain-Veyrac L Tilloy-Fenart Dorothée Vanuxeem Vincent Berezowski Roméo Cecchelli 《Pharmacological research》2007,56(1):11-17
PURPOSE: The objective of the current study was to determine the ability of some antiemetic compounds to cross the blood-brain barrier (BBB) and thereby to determine possible side effects of compounds for the central nervous system (CNS). METHODS: We compared the brain penetration of some antiemetic compounds using an in vitro BBB model consisting in brain capillary endothelial cells co-cultured with primary rat glial cells. RESULTS: This study clearly demonstrated that the metopimazine metabolite, metopimazine acid, has a very low brain penetration, lower than metopimazine and even less than the other antiemetic compounds tested in this study. CONCLUSIONS: The poor brain penetration of metopimazine acid, metopimazine biodisponible form, seems very likely related to the clinically observed difference in therapeutic and safety profile. 相似文献
999.
The synthesis of barbituric acid derivatives containing α-phenylskatyl residues substituted at C(5) is described. The initial compound was α-phenylnorgramine, which had been previously successfully used for the alkylation of a series of CH-acids, in particular, for the synthesis of diethyl-1H-indol-3-yl(phenyl)methylmalonate. This compound has been used to obtain a series of 2-thiobarbituric acid derivatives, which are expected to possess antioxidant, membrane protector, and radioprotector properties.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 1, pp. 29 – 33, January, 2005. 相似文献
1000.
Manuela Kusch Claudia Grundmann Stefanie Keitel Rainer Seitz Herbert K?nig 《Blood coagulation & fibrinolysis》2006,17(7):575-580
A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases. 相似文献