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R Hälg J Besserer M Boschung S Mayer U Schneider 《Radiation oncology (London, England)》2012,7(1):138-4
ABSTRACT: BACKGROUND: Due to the substantial increase in beam-on time of high energy intensity-modulated radiotherapy (>10 MV) techniques to deliver the same target dose compared to conventional treatment techniques, an increased dose of scatter radiation, including neutrons, is delivered to the patient. As a consequence, an increase in second malignancies may be expected in the future with the application of intensity-modulated radiotherapy. It is commonly assumed that the neutron dose equivalent scales with the number of monitor units. METHODS: Measurements of neutron dose equivalent were performed for an open and an intensity-modulated field at four positions: inside and outside of the treatment field at 0.2 cm and 15 cm depth, respectively. RESULTS: It was shown that the neutron dose equivalent, which a patient receives during an intensity-modulated radiotherapy treatment, does not scale with the ratio of applied monitor units relative to an open field irradiation. Outside the treatment volume at larger depth 35% less neutron dose equivalent is delivered than expected. CONCLUSIONS: The predicted increase of second cancer induction rates from intensity-modulated treatment techniques can be overestimated when the neutron dose is simply scaled with monitor units. 相似文献
63.
Lauren M Reynolds Elif Engin Gabriella Tantillo Hew Mun Lau John W Muschamp William A Carlezon Jr Uwe Rudolph 《Neuropsychopharmacology》2012,37(11):2531-2540
Benzodiazepines such as diazepam are widely prescribed as anxiolytics and sleep aids. Continued use of benzodiazepines, however, can lead to addiction in vulnerable individuals. Here, we investigate the neural mechanisms of the behavioral effects of benzodiazepines using the intracranial self-stimulation (ICSS) test, a procedure with which the reward-enhancing effects of these drugs can be measured. Benzodiazepines bind nonselectively to several different GABAA receptor subtypes. To elucidate the α subunit(s) responsible for the reward-enhancing effects of benzodiazepines, we examined mice carrying a histidine-to-arginine point mutation in the α1, α2, or α3 subunit, which renders the targeted subunit nonresponsive to diazepam, other benzodiazepines and zolpidem. In wild-type and α1-point-mutated mice, diazepam caused a dose-dependent reduction in ICSS thresholds (reflecting a reward-enhancing effect) that is comparable to the reduction observed following cocaine administration. This effect was abolished in α2- and α3-point-mutant mice, suggesting that these subunits are necessary for the reward-enhancing action of diazepam. α2 Subunits appear to be particularly important, since diazepam increased ICSS thresholds (reflecting an aversive-like effect) in α2-point-mutant animals. Zolpidem, an α1-preferring benzodiazepine-site agonist, had no reward-enhancing effects in any genotype. Our findings implicate α2 and α3 subunit containing GABAA receptors as key mediators of the reward-related effects of benzodiazepines. This finding has important implications for the development of new medications that retain the therapeutic effects of benzodiazepines but lack abuse liability. 相似文献
64.
Achim Schneider Alfredo Morabia Uwe Papendick Reinhard Kirchmayr 《Nutrition and cancer》2013,65(4):209-211
Clinical and ecological evidence supporting an association between human papillomavirus (HPV)‐related tumors and dietary factors are presented. Abstinence from high intake of fried pork (600–1,000 g/day) was associated with regression of an urethral condyloma in a healthy 19‐year‐old man treated with interferon gamma. International correlations suggest that pork intake is positively associated with incidence of cervical cancer, a disease also related to HPV. Pork meat or dietary factors associated with pork meat consumption may be involved in the development of HPV‐related diseases. 相似文献
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Giuseppe De Luca MD C. Michael Gibson MD Kurt Huber MD Uwe Zeymer MD Dariusz Dudek MD Donald Cutlip MD Francesco Bellandi MD Marko Noc MD Ayse Emre MD Simona Zorman MD H. Mesquita Gabriel MD Mauro Maioli MD Tomasz Rakowski MD Mariann Gyngysi MD Arnoud W.J. van't Hof MD 《American heart journal》2009,158(3):416-421
69.
Giugliano RP Roe MT Harrington RA Gibson CM Zeymer U Van de Werf F Baran KW Hobbach HP Woodlief LH Hannan KL Greenberg S Miller J Kitt MM Strony J McCabe CH Braunwald E Califf RM;INTEGRITI Investigators 《Journal of the American College of Cardiology》2003,41(8):1251-1260
OBJECTIVES: The goal of this study was to evaluate combinations of eptifibatide with reduced-dose tenecteplase (TNK) in ST-elevation myocardial infarction (STEMI). BACKGROUND: Glycoprotein IIb/IIIa inhibitors enhance thrombolysis. The role of combination therapy in clinical practice remains to be established. METHODS: Patients (n = 438) with STEMI <6 h were enrolled. In dose-finding, 189 patients were randomized to different combinations of double-bolus eptifibatide and reduced-dose TNK. In dose-confirmation, 249 patients were randomized 1:1 to eptifibatide 180 microg/kg bolus, 2 microg/kg/min infusion, and 180 microg/kg bolus 10 min later (180/2/180) plus half-dose TNK (0.27 mg/kg) or standard-dose (0.53 mg/kg) TNK monotherapy. All patients received aspirin and unfractionated heparin (60 U/kg bolus; infusion 7 U/kg/h [combination], 12 U/kg/h [monotherapy]). The primary end point was Thrombolysis In Myocardial Infarction (TIMI) grade 3 epicardial flow at 60 min. RESULTS: In dose-finding, TIMI grade 3 flow rates were similar across groups (64% to 68%). Arterial patency was highest for eptifibatide 180/2/180 plus half-dose TNK (96%, p = 0.02 vs. eptifibatide 180/2/90 plus half-dose TNK). In dose-confirmation, this combination, compared with TNK monotherapy, tended to achieve more TIMI 3 flow (59% vs. 49%, p = 0.15), arterial patency (85% vs. 77%, p = 0.17), and ST-segment resolution (median 71% vs. 61%, p = 0.08) but was associated with more major hemorrhage (7.6% vs. 2.5%, p = 0.14) and transfusions (13.4% vs. 4.2%, p = 0.02). Intracranial hemorrhage occurred in 1.0%, 0.6%, and 1.7% of patients treated with any combination, eptifibatide 180/2/180 and half-dose TNK, and TNK monotherapy, respectively. CONCLUSIONS: Double-bolus eptifibatide (180/2/180) plus half-dose TNK tended to improve angiographic flow and ST-segment resolution compared with TNK monotherapy but was associated with more transfusions and non-cerebral bleeding. Further study is needed before this combination can be recommended for general use. 相似文献
70.
Krüger S Graf J Merx MW Koch KC Kunz D Hanrath P Janssens U 《American heart journal》2004,147(1):60-65