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41.
Dana Schneider Mariangela Vicarioto Serelina Coluzzi Antonella Matteocci Nicoletta Revelli Barbara Foglieni Patrizia Artusi Donatella Londero Anna Quaglietta Giancarla Barrotta Domenico Visceglie Giuseppina Portararo Jonella Gilsdorf 《Trasfusione del sangue》2022,20(4):329
BackgroundABO antibody titres are important in many clinical decisions; however, much variability is observed in titre results. For reliable and reproducible titre results, automated ABO titration methods have been developed. In this 10-site study, we evaluated the equivalency of the automated ABO titration assays on the Galileo NEO, a fully automated blood bank analyzer (Immucor, Inc.) to manual titration with gel Column Agglutination Technology (CAT), as well as the reproducibility of both methods.Materials and methodsTen different locations participated in this study. The equivalency study included 70 random samples at each site. The reproducibility study tested the same blinded 30-sample panel at each study site. Anti-A and anti-B IgM and IgG antibody titres were tested with both the automated and manual methods; additionally, dithiothreitol (DTT) treatment was used to inactivate IgM antibodies in the manual CAT method.ResultsThe equivalency between CAT manual method and Galileo NEO automated titres at each site ranged from 38 to 88%; equivalency for each isotype was 66.2% for IgM, 60.6% for IgG, and 88.5% for DTT-treated IgG. The reproducibility study evaluated the titre variation of each sample obtained from the 10 sites. The average titre ranges (in doubling dilutions) for the automated and manual methods, respectively, were 2.15±1.0 and 4.03±1.8 for IgM, and 1.53±0.7 and 4.10±1.9 for IgG; for the manual DTT-treated IgG, the average titre range was 3.45±1.8 doubling dilutions.DiscussionThe results demonstrated that the Galileo NEO automated and manual CAT ABO titres are not equivalent. However, the study also demonstrated that titre reproducibility is enhanced with the Galileo NEO automated ABO titration assays relative to the manual CAT ABO titration method. Therefore, to improve management of patients receiving care across multiple institutions, our study supports the use of automated ABO titration. 相似文献
42.
Antioxidant properties of ursodeoxycholic acid 总被引:5,自引:0,他引:5
Lapenna D Ciofani G Festi D Neri M Pierdomenico SD Giamberardino MA Cuccurullo F 《Biochemical pharmacology》2002,64(11):1661-1667
We have investigated potential antioxidant properties of the clinically relevant bile acid UDCA, which reaches therapeutic concentrations up to 0.09 and 29 mM, respectively, in human plasma and bile. UDCA was an excellent scavenger of OHz.rad; generated by FeCl(3)-EDTA, H(2)O(2) and ascorbate in the deoxyribose oxidation test, showing IC(min) and IC(50) values of 0.02 and 0.2 mM, respectively, and a second-order rate constant for reaction with OHz.rad; of 2+/-0.1 x 10(10)M(-1)s(-1). Notably, the drug could enhance at 1.5 mM concentration the antioxidant capacity of human bile against OHz.rad;-induced deoxyribose oxidation. UDCA also showed antioxidant effects in the deoxyribose test performed with nonchelated iron ions, such as Fe(2+) plus H(2)O(2) (IC(min): 7 mM, IC(50): 20 mM) or Fe(3+) plus H(2)O(2) and ascorbate (IC(min): 0.3 mM, IC(50): 5 mM), and inhibited ferrozine-Fe(2+) and desferrioxamine-Fe(3+) complexes formation with IC(50) values of, respectively, 12 and 0.3 mM, indicating that the drug interacts more with iron(III) than with iron(II). Moreover, UDCA significantly inhibited phospholipid liposome peroxidation induced by the OHz.rad;-generating system FeCl(3)-EDTA, H(2)O(2) and ascorbate (IC(min): 0.75 mM, IC(50): 3 mM), and by peroxyl radicals generated in the aqueous phase by AAPH (IC(min): 8 mM, IC(50): 14 mM). UDCA, even at 25 mM concentration, was ineffective on the lipoperoxidation mediated by Fe(2+) alone, but at the same concentration counteracted significantly that by Fe(3+) plus ascorbate, further pointing to its preferential antioxidant interaction with iron(III).In conclusion, UDCA has direct antioxidant properties, which are especially relevant against Fe(3+)- and OHz.rad;-dependent biomolecular oxidative damage; such properties are evident at therapeutically relevant drug concentrations, suggesting that UDCA could act as an antioxidant in vivo. 相似文献
43.
Domenico Tric Sarah McCollum Stephanie Samuels Nicola Santoro Alfonso Galderisi Leif Groop Sonia Caprio Veronika Shabanova 《Diabetes care》2022,45(8):1841
OBJECTIVEIn a large, multiethnic cohort of youths with obesity, we analyzed pathophysiological and genetic mechanisms underlying variations in plasma glucose responses to a 180 min oral glucose tolerance test (OGTT).RESEARCH DESIGN AND METHODSLatent class trajectory analysis was used to identify various glucose response profiles to a nine-point OGTT in 2,378 participants in the Yale Pathogenesis of Youth-Onset T2D study, of whom 1,190 had available TCF7L2 genotyping and 358 had multiple OGTTs over a 5 year follow-up. Insulin sensitivity, clearance, and β-cell function were estimated by glucose, insulin, and C-peptide modeling.RESULTSFour latent classes (1 to 4) were identified based on increasing areas under the curve for glucose. Participants in class 3 and 4 had the worst metabolic and genetic risk profiles, featuring impaired insulin sensitivity, clearance, and β-cell function. Model-predicted probability to be classified as class 1 and 4 increased across ages, while insulin sensitivity and clearance showed transient reductions and β-cell function progressively declined. Insulin sensitivity was the strongest determinant of class assignment at enrollment and of the longitudinal change from class 1 and 2 to higher classes. Transitions between classes 3 and 4 were explained only by changes in β-cell glucose sensitivity.CONCLUSIONSWe identified four glucose response classes in youths with obesity with different genetic risk profiles and progressive impairment in insulin kinetics and action. Insulin sensitivity was the main determinant in the transition between lower and higher glucose classes across ages. In contrast, transitions between the two worst glucose classes were driven only by β-cell glucose sensitivity. 相似文献
44.
Histopathologic examination and clinical observations of solid and haematological malignancies indicates mast cells as key host cells in the tumour infiltrate, with important consequence on tumour-associated angiogenesis and tumour growth. Data suggest indeed that tumour-infiltrating mast cells may exert a prominent function in the angiogenic "switch", which is essential for the progression of early tumours. The experimental approach has substantially increased our understanding of the role of tumour-infiltrating mast cells in the process of angiogenesis that accompanies tumour development. This review will focus on the crucial contribution of mast cells in promoting tumour neovascularization as it emerges from the most recent observations of experimental carcinogenesis in in vivo and in vitro models. 相似文献
45.
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48.
Gennaro Daniele Clorinda Schettino Laura Arenare Domenico Bilancia Fabio Farinati Piera Federico Stefano Tamberi Gino Crivellari Sandro Barni Raffaella Tortora Francesco Izzo Antonio Frassoldati Luigi Cavanna Claudia Mucciarini Luigi Bolondi Angelo Dinota Filippo Pelizzaro Maria Carmela Piccirillo Piera Gargiulo Massimo Di Maio Ciro Gallo Francesco Perrone Bruno Daniele 《肝癌研究(英文版)》2021,7(7):52-65
Aim: Only patients with good liver function {[Child-Pugh (CP)] A class} were eligible for trials testing sorafenib as first-line treatment of hepatocellular car... 相似文献
49.
Davide L. Vetrano Maria S. Pisciotta Alice Laudisio Maria R. Lo Monaco Graziano Onder Vincenzo Brandi Domenico Fusco Beatrice Di Capua Diego Ricciardi Roberto Bernabei Giuseppe Zuccalà 《Journal of the American Medical Directors Association》2018,19(6):523-527
Objectives
In Parkinson disease (PD), sarcopenia may represent the common downstream pathway that from motor and nonmotor symptoms leads to the progressive loss of resilience, frailty, and disability. Here we (1) assessed the prevalence of sarcopenia in older adults with PD using 3 different criteria, testing their agreement, and (2) evaluated the association between PD severity and sarcopenia.Design
Cross-sectional, observation study.Setting
Geriatric day hospital.Participants
Older adults with idiopathic PD.Measurements
Body composition was evaluated through dual energy x-ray absorptiometry. Handgrip strength and walking speed were measured. Sarcopenia was operationalized according to the Foundation for the National Institutes of Health, the European Working Group on Sarcopenia in Older Persons, and the International Working Group. Cohen k statistics was used to test the agreement among criteria.Results
Among the 210 participants (mean age 73 years; 38% women), the prevalence of sarcopenia was 28.5%–40.7% in men and 17.5%–32.5% in women. The prevalence of severe sarcopenia was 16.8%–20.0% in men and 11.3%–18.8% in women. The agreement among criteria was poor. The highest agreement was obtained between the European Working Group on Sarcopenia in Older Persons (severe sarcopenia) and International Working Group criteria (k = 0.52 in men; k = 0.65 in women; P < .01 for both). Finally, severe sarcopenia was associated with PD severity (odds ratio 2.30; 95% confidence interval 1.15–4.58).Conclusions
Sarcopenia is common in PD, with severe sarcopenia being diagnosed in 1 in every 5 patients with PD. We found a significant disagreement among the 3 criteria evaluated, in detecting sarcopenia more than in ruling it out. Finally, sarcopenia is associated with PD severity. Considering its massive prevalence, further studies should address the prognosis of sarcopenia in PD. 相似文献50.
Francesco Landi Riccardo Calvani Matteo Tosato Anna Maria Martone Domenico Fusco Alex Sisto Elena Ortolani Giulia Savera Sara Salini Emanuele Marzetti 《Journal of the American Medical Directors Association》2017,18(1):88.e17-88.e24