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The nature of focal areas of hyperfluorescence or hot spots imaged with indocyanine green angiography 总被引:9,自引:0,他引:9
Fernandes LH Freund KB Yannuzzi LA Spaide RF Huang SJ Slakter JS Sorenson JA 《Retina (Philadelphia, Pa.)》2002,22(5):557-568
PURPOSE: To clarify the frequency and nature of ICG angiographic "hot spots" seen in patients with neovascular age-related macular degeneration (ARMD). METHODS: A consecutive series of newly diagnosed patients with neovascular ARMD and fluorescein angiographic evidence of occult choroidal neovascularization (occult CNV) was imaged with ICG angiography. Eyes with ICG angiographic "hot spots" were identified and further classified. A hot spot was defined as any area of abnormal hyperfluorescence, in the mid to late stages of ICG angiography, measuring less than 1 disk area in size. RESULTS: From a total of 190 patients (220 eyes) with neovascular ARMD, 30 patients and 34 eyes (16%) with hot spots were identified. Hot spots were noted to be of three distinct patterns: polypoidal choroidal neovascularization (polypoidal CNV) in 21 of 34 eyes, or 62%; retinal angiomatous proliferation (RAP) in 11 of 34 eyes, or 30%; and focal occult CNV in 2 of 34 eyes, or 8%. CONCLUSIONS: A focal area of intense hyperfluorescence or so-called hot spot seen on ICG angiography in neovascular ARMD is due to one of three possible forms of neovascularization: most frequently polypoidal CNV, less commonly RAP, and infrequently nonspecific, focal occult CNV. Since neovascular ARMD may be caused by different types of neovascularization, each with distinct clinical manifestations, natural course, visual prognosis, and response to treatment, it is important to identify the precise nature of hot spots to establish an accurate diagnosis and, when appropriate, a specific form of management. 相似文献
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Cu, Fe, Mn, and Zn chelates offer a medicinal chemistry approach to overcoming radiation injury 总被引:1,自引:0,他引:1
Sorenson JR 《Current medicinal chemistry》2002,9(6):639-662
This review points out that treatment with essential metalloelement (Cu, Fe, Mn, and Zn) chelates facilitate tissue repair processes required for recovery from radiation injury including survival of lethally irradiated mice and rats. Results of studies pertaining to successful uses of bioavailable essential metalloelement chelates and combinations of them as well as aminothiols, Ca-channel blockers, acyl Melatonin homologs, substituted anilines, and curcumin radioprotectants are included in this review to suggest their use as chelates in overcoming radiation injury. Additional reports document that non-toxic doses of essential metalloelement chelates are effective in increasing survival and repairing radiation injury when administered before irradiation, in the radiation protection paradigm, and effective in increasing survival when used to treat after irradiation, in the radiorecovery paradigm. There are no other agents known to be effective in increasing survival when they are used to treat after irradiation. These approaches to radioprotection and radiorecovery offer promising approaches to facilitating recovery from radiation-induced injury experienced by patients undergoing radiation therapy for their neoplastic disease and by individuals who experience environmental, occupational, or accidental exposure to ionizing radiation. These individuals include those exposed to radiation resulting from nuclear accidents, the use of depleted uranium missiles, and astronauts undertaking space travel. Since there are no existing safe and effective treatments of radiation injury, studies of essential metalloelement chelates and combinations of them, as well as combinations of them with existing radioprotectant aminothiols, Ca-channel blockers, acyl Melatonin homologs, substituted anilines, and curcumin as radioprotectants seem worthwhile. 相似文献
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The authors sought to determine trends in the incidence of ALS in Olmsted County from 1925 to 1998. Seventy-seven cases of ALS were identified during the period studied. The incidence rate remained stable at 1.7 cases per 100,000 people per year. Mean age at onset was 63 years. Mean survival was 23 months from diagnosis. Mean survival for patients <60 years old was 31 months; for patients aged >or=60 years, it was 20 months (p = 0.02). Mean time from symptom onset to diagnosis was 13 months. Neither survival nor time to diagnosis changed significantly over time. 相似文献
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M. Albert Thomas Lawrence N. Ryner Minesh P. Mehta Patrick A. Turski James A. Sorenson 《Journal of magnetic resonance imaging : JMRI》1996,6(3):453-459
Application of two-dimensional (2D) J-resolved MR spectroscopy, fully localized in three dimensions to monitor the metabolites in human brain tumors in vivo on a whole body MR scanner is presented. A modified PRESS sequence with [90° – 180° – t1/2 – 180° – t1/2-acquisition] was used for voxel localization (2D J point-resolved spectroscopy [PRESS]); chemical shift selective (CHESS) sequence was used for suppression of water. The incremental delay (t1/2) added to the intervals before and after the last slice-selective 180° RF pulse allowed the monitoring of the J-evolution in a localized 2D NMR spectrum. The addition of the second frequency dimension in 2D J-resolved spectroscopy to encode the indirect spin-spin coupling allowed the visualization of lactate peaks not observed in the 1D MR spectrum because of severe overlap with lipid peaks. 2D spectra of a two-layer phantom with 100 mM alanine and corn oil and also from three patients with tumors are presented here. The 2D spectra show that the J-coupled lactate peaks could be separated even when the lipids peaks severely overlap. 相似文献