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171.
PURPOSE: To quantify the oxidative tissue damage after phacoemulsification, correlate the damage to the energy applied, and investigate the influence of ophthalmic viscosurgical devices (OVDs). SETTING: Department of Ophthalmology, University of Mainz, Mainz, Germany. METHODS: The study comprised 130 eyes operated on by 1 surgeon using the same phacoemulsification machine. Some eyes received an OVD before phacoemulsification and some did not. Energy values were expressed as phaco time; that is, ultrasound (US) time (seconds) after conversion to 100% phaco power. Patients were grouped as follows: Group 1, phaco time less than 20 seconds and no OVD; Group 2, phaco time 20 to 40 seconds and no OVD; Group 3, phaco time more than 40 seconds and no OVD; Group 4, phaco time 20 to 40 seconds and hydroxypropyl methylcellulose 2% (HPMC); Group 5, phaco time 20 to 40 seconds and sodium hyaluronate 1%. Aqueous humor from pseudophakic eyes served as a control. At the end of surgery, anterior chamber fluid was analyzed for lipid peroxides using the thiobarbituric acid method. RESULTS: Lipid peroxides were detected in all groups. The values were significantly higher in Group 2 than in Group 1 (P<.01) and in Group 3 than in Groups 1 and 2 (P<.01). The differences in lipid peroxide values between all phaco groups and the control group were statistically significant. Sodium hyaluronate 1% and HPMC 2% produced significantly lower lipid peroxide values than in the respective phaco groups that did not receive an OVD (both P<.01). CONCLUSIONS: Oxidative tissue damage occurred during phacoemulsification. The damage, which correlated with the US energy applied, can be reduced by the use of OVDs. 相似文献
172.
Late postoperative opacification of MemoryLens hydrophilic acrylic intraocular lenses: case series and review 总被引:2,自引:0,他引:2
Tehrani M Mamalis N Wallin T Dick HB Stoffelns BM Olson R Fry LL Clifford WS 《Journal of cataract and refractive surgery》2004,30(1):115-122
PURPOSE: To report clinical and spectrographic analyses of 2 explanted hydrophilic acrylic intraocular lenses (IOLs). SETTING: John A. Moran Eye Center, Salt Lake City, Utah, USA, and Johannes Gutenberg-University, Department of Ophthalmology, Mainz, Germany. METHODS: We report 6 cases of opacification of MemoryLens IOLs (Ciba Vision) that occurred approximately 2 years after implantation. The anterior and posterior surfaces of the IOLs had a white, frosted appearance, and the IOLs' interior looked brown, similar to the appearance of a brunescent cataract. Two of the IOLs were explanted because of a significant decrease in visual acuity. The IOLs were sent for further clinicopathologic analysis including scanning electron microscopy and energy dispersive x-ray spectroscopy (EDX). RESULTS: Microscopic analysis revealed multiple, fine, granular deposits of various sizes on the surface of the lens optics. The EDX analysis showed the presence of calcium within the deposits. CONCLUSIONS: Our cases show that hydrophilic acrylic IOLs can opacify even years after implantation. Analysis of the explanted IOLs revealed calcification. 相似文献
173.
BACKGROUND: Reliable chemosensitivity testing of head and neck squamous cell carcinoma (HNSCC) still faces methodical limitations. Since stromal cell contamination has been found to preclude reliable radiosensitivity testing of HNSCC as well as chemosensitivity testing of lung tumors, the present study investigates the impact of stromal cell contamination on chemosensitivity testing of HNSCC. PATIENTS AND METHODS: Seventeen biopsies from HNSCC were analyzed. The specimens were investigated using an ex vivo colony formation assay which allows for the quantitative and separate determination of the overall, as well as the epithelial, and stromal response to carboplatin, 5-fluorouracil and docetaxel. RESULTS: The overall chemoresponse was dominated by stromal cell multidrug resistance. However, by selective evaluation of the epithelial chemoresponse, individual chemosensitivity patterns could be identified. CONCLUSION: Multidrug-resistant stromal cells preclude the reliable assessment of the chemoresponse of HNSCC specimens. Carefiul correction for stromal cell effects is a prerequisite for the generation of therapeutically useful information. 相似文献
174.
175.
J. Rüdiger?Siewert Burkhard H.A.?von RahdenEmail author Hubert J.?Stein 《Esophagus》2004,1(4):147-159
Esophageal cancer and its treatment differ largely between the West and the East because West and East are concerned – at least in part – with different diseases: squamous cell cancers are the prevailing tumor type in Japan and other parts of Asia whereas this entity is now clearly outnumbered in Europe and North America by esophageal adenocarcinoma. The latter are mostly Barretts cancers, arising within the precancerous Barretts esophagus, promoted by the chronically damaging effect of gastro-esophageal reflux. The epidemiological differences entail differences in treatment concepts: esophageal cancer in principle is a surgical disease in Japan, with a high prevalence of early tumor stages in everyday clinical practice. In the West, a majority of esophageal cancers are seen in an advanced stage. Many tumors, in which R0 resection by primary surgery is unlikely, are approached with neo-adjuvant protocols that aim at downsizing of the tumor/downstaging of the disease before subsequent surgical resection. In Japan, by contrast, multimodal therapy is preferentially used in the adjuvant setting, in patients regarded at risk for recurrence. There have also been several very similar developments in the West and the East, especially the improved prognosis after esophageal cancer resection. Better long-term results (prolonged survival) are closely related to improved short-term results (decrease of morbidity and mortality) after esophagectomy. Both effects are multifactorial in nature and are attributable to better patient selection (risk analysis, improved staging), standardization of surgical techniques, and concentration of treatment in specialized high-volume centers.This lecture was presented during the international session at the 58th Annual Meeting of the Japan Esophageal Society 相似文献
176.
Krepler C Certa U Wacheck V Jansen B Wolff K Pehamberger H 《The Journal of investigative dermatology》2004,123(4):664-669
177.
Prudlo J Alber B Kalscheuer VM Roemer K Martin T Dullinger J Sittinger H Niemann S Heutink P Ludolph AC Ropers HH Zang K Meyer T 《Annals of neurology》2004,55(1):134-138
A chromosomal translocation t(18;21)(q23;q22) is reported in a patient with frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). We exclude the physical involvement and silencing of the ALS-linked gene for copper/zinc superoxide dismutase (SOD1) on chromosome 21q22.1. The breakpoints are assigned to sequences flanked by the markers ATA1H06, D18S462, D21S1915, and D21S1898. These critical regions may contain susceptibility loci for FTD associated with ALS. 相似文献
178.
Stoeckelhuber BM Wiesmann M Kreft B Stoeckelhuber M Weiss HD Bergmann-Koester CU 《R?ntgenpraxis; Zeitschrift für radiologische Technik》2004,55(5):167-174
PURPOSE: We evaluated different techniques of contrast-enhanced phase-inversion ultrasound to visualize renal perfusion. MATERIALS AND METHODS: Levovist contrast-enhanced phase-inversion ultrasound with different levels of mechanical index and frame rate was performed in 20 kidneys. Analysis using a software algorithm for time-resolved perfusion imaging was compared to single-image analysis performed by three independent radiologists. RESULTS: Optimal depiction of renal perfusion was achieved only by using a mechanical index which was high enough to destroy the microbubbles of the contrast agent (burst imaging) combined with a low frame rate (0.5 images/second). Renal cortex and medulla showed a homogeneous enhancement. Computer-assisted time-resolved perfusion analysis was applicable; it did not show additional Information to single-image analysis. CONCLUSION: Renal perfusion can be visualized using contrast-enhanced phase-inversion ultrasound. For depiction of bigger vessels, it is equal to B-mode ultrasound or Doppler mode techniques; however, it is superior for visualization of renal parenchymal perfusion. 相似文献
179.
The influence of interleukin 4 (IL-4) on antibody titer in serum and spleen culture supernatant in mice immunized with spinach (Spinacia oleracea L.) Rubisco was investigated. Therefore, we boosted one mouse additionally to the antigen with recombinant mouse IL-4. We found that the Rubisco-specific antibody titer in serum as well as in spleen cell culture supernatant was significantly enhanced in the IL-4 mouse. Most of the antibodies were of the IgG1 subclass. After hybridoma generation, Rubisco-specific antibodies were found in more than 95% of the wells tested compared to about 12% of the control mouse. 相似文献
180.
Weinberger AW Dahlke C Schlossmacher B Hermel M Schrage NF Kirchhof B 《American journal of ophthalmology》2004,137(3):590-1; author reply 591