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76.
Biswajit Kumar Biswas Sutapa Dey Anindya Chakrabarty Arghya Laha Tapan Kumar Mandal Laxmikanta Karmakar Debajyoti Das 《Artificial organs》2020,44(11):E494-E508
Cartilage is avascular with limited to no regenerative capacity, so its loss could be a challenge for reconstructive surgery. Current treatment options for damaged cartilage are also limited. In this aspect there is a tremendous need to develop an ideal cartilage-mimicking biomaterial that could repair maxillofacial defects. Considering this fact in this study we have prepared twelve silicone-based materials (using Silicone 40, 60, and 80) reinforced with hydroxyapatite, tri-calcium phosphate, and titanium dioxide which itself has proven their efficacy in several studies and able to complement the shortcomings of using silicones. Among the mechanical properties (Young’s modulus, tensile strength, percent elongation, and hardness), hardness of Silicone-40 showed similarities with goat ear (P > .05). Silicone peaks have been detected in FTIR. Both AFM morphology and SEM images of the samples confirmed more roughed surfaces. All the materials were nonhemolytic in hemocompatibility tests, but among the twelve materials S2, S3, S5, and S6 showed the least hemolysis. For all tested bacterial strains, adherence was lower on each material than that grown on the plain industrial silicone material which was used as a positive control. S2, S3, S5, and S6 samples were selected as the best based on mechanical characterizations, surface characterizations, in vitro hemocompatibility tests and bacterial adherence activity. So, outcomes of this present study would be promising when developing ideal cartilage-mimicking biocomposites and their emerging applications to treat maxillofacial defects due to cartilage damage. 相似文献
77.
Rupak Shivakoti Nikhil Gupte Wei-Teng Yang Noluthando Mwelase Cecilia Kanyama Alice M. Tang Sandy Pillay Wadzanai Samaneka Cynthia Riviere Sima Berendes Javier R. Lama Sandra W. Cardoso Patcharaphan Sugandhavesa Richard D. Semba Parul Christian Thomas B. Campbell Amita Gupta the NWCS PEARLS study team 《Nutrients》2014,6(11):5061-5078
A case-cohort study, within a multi-country trial of antiretroviral therapy (ART) efficacy (Prospective Evaluation of Antiretrovirals in Resource Limited Settings (PEARLS)), was conducted to determine if pre-ART serum selenium deficiency is independently associated with human immunodeficiency virus (HIV) disease progression after ART initiation. Cases were HIV-1 infected adults with either clinical failure (incident World Health Organization (WHO) stage 3, 4 or death by 96 weeks) or virologic failure by 24 months. Risk factors for serum selenium deficiency (<85 μg/L) pre-ART and its association with outcomes were examined. Median serum selenium concentration was 82.04 μg/L (Interquartile range (IQR): 57.28–99.89) and serum selenium deficiency was 53%, varying widely by country from 0% to 100%. In multivariable models, risk factors for serum selenium deficiency were country, previous tuberculosis, anemia, and elevated C-reactive protein. Serum selenium deficiency was not associated with either clinical failure or virologic failure in multivariable models. However, relative to people in the third quartile (74.86–95.10 μg/L) of serum selenium, we observed increased hazards (adjusted hazards ratio (HR): 3.50; 95% confidence intervals (CI): 1.30–9.42) of clinical failure but not virologic failure for people in the highest quartile. If future studies confirm this relationship of high serum selenium with increased clinical failure, a cautious approach to selenium supplementation might be needed, especially in HIV-infected populations with sufficient or unknown levels of selenium. 相似文献
78.
Balakrishnan V Unnikrishnan AG Thomas V Choudhuri G Veeraraju P Singh SP Garg P Pai CG Devi RN Bhasin D Jayanthi V Premalatha N Chacko A Kar P Rai RR Rajan R Subhalal N Mehta R Mishra SP Dwivedi M Vinayakumar KR Jain AK Biswas K Mathai S Varghese J Ramesh H Alexander T Philip J Raj VV Vinodkumar A Mukevar S Sawant P Nair P Kumar H Sudhindran S Dhar P Sudheer OV Sundaram KR Tantri BV Singh D Nath TR 《JOP : Journal of the pancreas》2008,9(5):593-600
79.
Cooperative inhibition of NF-kappa B and Tat-induced superactivation of human immunodeficiency virus type 1 long terminal repeat. 总被引:5,自引:0,他引:5 下载免费PDF全文
D K Biswas C M Ahlers B J Dezube A B Pardee 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(23):11044-11048
Human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR)-regulated gene expression is stimulated independently by the cellular trans-activator NF-kappa B and the viral protein Tat. Noncytotoxic concentrations of the drug pentoxifylline (PTX) inhibited interaction of NF-kappa B with its motif and the stimulation of HIV-1 LTR-driven gene expression in Jurkat cells. Tat protein (from a cotransfected Tat-expression vector) also induced activation of HIV-1 LTR-driven gene expression. This activation was unaffected by PTX when NF-kappa B sites in the HIV-1 LTR were mutated, suggesting that this drug does not directly influence Tat function, which, however, was inhibited by the Tat-inhibitor Ro 24-7429. Transient reporter gene expression regulated by HIV-1 LTR with wild-type NF-kappa B motifs in the presence of Tat protein was 10- to 60-fold higher than in the presence of either of the trans-activators alone, demonstrating superactivation of HIV-1 LTR by the concerted action of both the trans-activators. Treatment of cells with either PTX or Ro 24-7429 inhibited this superactivation of the HIV-1 LTR. The inhibitory effect of these two drugs in combination, at concentrations that alone did not significantly influence viral promoter activity, was far more than additive. A cooperative action of PTX (NF-kappa B inhibitor) and Ro 24-7429 (Tat inhibitor) on HIV-1 LTR-regulated gene expression is suggested. Concentrations of the drugs that induced maximum inhibition of HIV-1 LTR through their cooperative action are far below cytotoxic levels. Thus, the combination of these two inhibitors could be very effective for anti-HIV therapy. 相似文献
80.
Debangshu Das Banani Bindhani Bidisha Mukherjee Hirak Saha Priyanka Biswas Kaustav Dutta Priyanka Prasad Dona Sinha Manas Ranjan Ray 《International journal of public health》2014,59(4):655-663