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991.
Serena Tongiani Tetsuya Ozeki Valentino J. Stella 《Journal of pharmaceutical sciences》2009,98(12):4769-4780
The aim of this work was to study the complexation capability of new sulfobutyl ether-alkyl ether (SBE-AE-CD) mixed β- and γ-cyclodextrin derivatives with a series of structurally related steroids (6α-methylprednisolone, prednisolone, triamcinolone, D(?) norgestrel and hydrocortisone) and a number of dihydropyridine calcium channel blockers (nimodipine, nitrendipine, nifedipine) that traditionally interact poorly with other cyclodextrins (CDs). The effect of the total degree of substitution (TDS) and of the length of the alkyl side chain on binding capacity of these new modified CDs was evaluated as was their ability to induce red blood cell hemolysis. An attempt was made to correlate hemolysis to surface activity. Binding constants between the SBE-AE-CDs and selected molecules were determined by spectroscopic studies, and only in few cases by solubility studies. Hemolysis percentage was determined using citrated rabbit blood and citrated human blood with UV analysis. The surface activity was measured with a tensiometer. A significant improvement in the binding capacity between various substrates and the new SBE-AE-CDs was observed when compared to the SBE-CDs. The length of the alkyl chain and total degree of alkylation affected the binding with the relationship being complex. For most compounds, an intermediate degree of substitution appeared to be advantageous. The hemolysis studies showed that some of the derivatives may induce hemolysis and this correlated with higher surface activity for some but not all of the derivatives. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4769–4780, 2009 相似文献
992.
993.
Calogero Terregino Anna Toffan Maria Serena Beato Roberta De Nardi Marta Vascellari Amelio Meini 《Avian pathology》2008,37(5):487-493
The aims of this study were firstly to evaluate the pathogenicity of an Italian isolate of the QX strain of infectious bronchitis (IB) virus using 1-day-old female specific pathogen free chicks (layer type) and 1-day-old female commercial broiler type chickens, and secondly to assess the level of protection induced in these birds by a vaccination programme including the IB Massachusetts and 4/91 serotype live attenuated vaccines. Unvaccinated birds showed clinical signs of varying severity, predominantly affecting the upper respiratory tract. Vaccinated birds appeared healthy, with the exception of a very mild conjunctivitis affecting a limited number of the broilers. Vaccination fully protected specific pathogen free birds, since no histopathological lesions were observed, nor was virus detected following challenge. In broilers, replication of the challenge virus was not prevented but was significantly reduced. This study confirms that vaccination at 1 day old and at 14 days of age using the Ma5 and 4/91 IB vaccines may be instrumental in reducing the economic impact of QX IB virus infections in layer and broiler farms. 相似文献
994.
Franca R Guerini Serena Delbue Milena Zanzottera Cristina Agliardi Marina Saresella Roberta Mancuso Renato Maserati Enrico Marchioni Andrea Gori Pasquale Ferrante 《Biomedicine & Pharmacotherapy》2008,62(1):26-30
Progressive Multifocal Leukoencephalopathy (PML) is a fatal demyelinating disease of the central nervous system (CNS) caused by JC virus (JCV), a human polyomavirus that can lytically infect and destroy the oligodendrocites in immunosuppressed individuals. After the introduction of highly active antiretroviral therapy (HAART) for AIDS treatment, a PML-like leukoencephalopathy, known as non-determined leukoencephalopathy (NDLE), has also been observed. Since a number of host genetic factors have been identified as having an impact on susceptibility to HIV-1 infection and in the progression to AIDS and death, in this work we analysed the pattern of distribution of different chemokine and chemokine receptor polymorphisms that seem to be involved in HIV+ neurological diseases. The CCR5, RANTES, CCR2 and SDF1 genes were molecularly analysed in 84 HIV+ HAART treated subjects: 55 without neurological disorders (HIV+), 12 HIV+ NDLE and 17 HIV+ PML patients. The RANTES -403 G/A polymorphism was significantly associated with NDLE. These data suggest that mutation of the RANTES allele can predispose to the induction of demyelination similarly to what has been observed in Multiple Sclerosis (MS) and may suggest a possible explanation for the development of leukoencephalopathy without detection of JCV. 相似文献
995.
Vincenzo Pucci Serena Di Palma Anna Alfieri Fabio Bonelli Edith Monteagudo 《Journal of pharmaceutical and biomedical analysis》2009,50(5):867-871
A novel strategy to minimize phospholipids-based matrix effects in bioanalytical LC–MS/MS assays was evaluated. The phospholipids-based matrix effect was investigated with a commercially available electrospray ionization (ESI) source coupled with a triple quadrupole mass spectrometer. A systematic comparison approach of two sample preparation procedures was performed. In particular, the matrix effect on mass spectrometry response in rat and human plasma samples was studied by comparing sample extracts obtained by means of a conventional plasma protein precipitation with acetonitrile and the novel HybridSPE-Precipitation procedure.The HybridSPE dramatically reduced the levels of residual phospholipids in biological samples, leading to significant reduction in matrix effects. This new procedure which combines the simplicity of precipitation with the selectivity of SPE allows to obtain much cleaner extracts than with conventional procedures. The effective targeted removal of phospholipids and proteins in biological plasma samples achieved with the HybridSPE-Precipitation procedure provides significant improvement in bioanalysis and a practical and fast way to ensure the avoidance of phospholipids-based matrix effects. 相似文献
996.
Annalisa Grimaldi Gianluca Tettamanti Francesco Acquati Elena Bossi Maria Luisa Guidali Serena Banfi Laura Monti Roberto Valvassori Magda de Eguileor 《Developmental dynamics》2008,237(3):659-671
Our study focuses on the possible involvement of the Hedgehog (Hh) pathway in the differentiation of striated muscle fibres in cuttlefish (Sepia officinalis) mantle. We show here that both an hh-homolog signalling molecule and its receptor Patched (Ptc) are expressed in a specific population of myoblasts which differentiates into the radial fast fibres. To evaluate the functional significance of hh expression in developing cuttlefish, we inhibited the Hedgehog signalling pathway by means of cyclopamine treatment in cuttlefish embryos. In treated embryos, the gross anatomy was considerably compromised, displaying an extremely reduced mantle with a high degree of morphological abnormalities. TUNEL and BrdU assays showed that the absence of an hh signalling induces apoptosis and reduces the proliferation rate of muscle precursors. We therefore hypothesize a possible involvement of Hh and its receptor Ptc in the formation of striated muscle fibres in cuttlefish. 相似文献
997.
998.
Preterm birth is associated with a high prevalence of neuropsychiatric impairment in childhood and adolescence, but the neural correlates underlying these disorders are not fully understood. Quantitative magnetic resonance imaging techniques have been used to investigate subtle differences in cerebral growth and development among children and adolescents born preterm or with very low birth weight. Diffusion tensor imaging and computer-assisted morphometric techniques (including voxel-based morphometry and deformation-based morphometry) have identified abnormalities in tissue microstructure and cerebral morphology among survivors of preterm birth at different ages, and some of these alterations have specific functional correlates. This chapter reviews the literature reporting differential brain development following preterm birth, with emphasis on the morphological changes that correlate with neuropsychiatric impairment. 相似文献
999.
Martini E Ghelardini C Bertucci C Dei S Gualtieri F Guandalini L Manetti D Scapecchi S Teodori E Romanelli MN 《Medicinal chemistry (Shāriqah (United Arab Emirates))》2005,1(5):473-480
The enantiomers of the potent cognition-enhancer DM232 ((1), unifiram) and of its isopropylsulfonyl analog (2), which is endowed with amnesic properties, have been synthesized using (S)- and (R)-5-(hydroxymethyl)-2-pyrrolidinone as chiral precursors. The enantiomeric excess was determined by means of capillary electrophoresis, and found higher than 99.9 %. DM232 enantiomers were tested as cognition-enhancers in the passive-avoidance and social learning tests, and their ability to induce ACh release from rat cerebral cortex was also determined; in all the performed essays, (R)-(+)-(1) displayed higher potency than its (S)-(-) enantiomer, being able to elicit comparable effects at 3-fold to 10-fold lower doses. On the contrary, (R)-(+) and (S)-(-)-(2) showed the same amnesic potency when tested in the passive-avoidance test. These findings may be useful to clarify the mechanism of action of these substances. 相似文献
1000.
Daily intake of a formulated tomato drink affects carotenoid plasma and lymphocyte concentrations and improves cellular antioxidant protection 总被引:4,自引:0,他引:4
Porrini M Riso P Brusamolino A Berti C Guarnieri S Visioli F 《The British journal of nutrition》2005,93(1):93-99
The salutary characteristics of the tomato are normally related to its content of carotenoids, especially lycopene, and other antioxidants. Our purpose was to verify whether the daily intake of a beverage prototype called Lyc-o-Mato((R)) containing a natural tomato extract (Lyc-o-Mato((R)) oleoresin 6 %) was able to modify plasma and lymphocyte carotenoid concentrations, particularly those of lycopene, phytoene, phytofluene and beta-carotene, and to evaluate whether this intake was sufficient to improve protection against DNA damage in lymphocytes. In a double-blind, cross-over study, twenty-six healthy subjects consumed 250 ml of the drink daily, providing about 6 mg lycopene, 4 mg phytoene, 3 mg phytofluene, 1 mg beta-carotene and 1.8 mg alpha-tocopherol, or a placebo drink. Treatments were separated by a wash-out period. Plasma and lymphocyte carotenoid and alpha-tocopherol concentrations were determined by HPLC, and DNA damage by the comet assay. After 26 d of consumption of the drink, plasma carotenoid levels increased significantly: concentrations of lycopene were 1.7-fold higher (P<0.0001); of phytofluene were 1.6-fold higher (P<0.0001); of phytoene were doubled (P<0.0005); of beta-carotene were 1.3-fold higher (P<0.05). Lymphocyte carotenoid concentrations also increased significantly: that of lycopene doubled (P<0.001); that of phytofluene was 1.8-fold higher (P<0.005); that of phytoene was 2.6-fold higher (P<0.005); that of beta-carotene was 1.5-fold higher (P<0.01). In contrast, the alpha-tocopherol concentration remained nearly constant. The intake of the tomato drink significantly reduced (by about 42 %) DNA damage (P<0.0001) in lymphocytes subjected to oxidative stress. In conclusion, the present study supports the fact that a low intake of carotenoids from tomato products improves cell antioxidant protection. 相似文献