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991.
Compound YSY-01A, a recently synthesized proteasome inhibitor, has shown potent growth-inhibitory effect on tumor cells in previous researches. However, the mechanism of its inhibitory effects, especially on cell cycle, remains largely unclear. This study aimed to evaluate the correlation between cell cycle arrest effect of YSY-01A and its anti-cancer effect, and to probe the possible molecular mechanisms for its effects on human ovarian cancer SK-OV-3 cells. The results suggested that YSY-01A significantly (P<0.05) inhibited cellular proliferation of SK-OV-3 cells in a concentration-dependent and time-dependent manner. Furthermore, YSY-01A induced a G2/M cell cycle arrest of SK-OV-3 cells. Further investigation revealed that YSY-01A significantly (P<0.05) changed the expression levels of a series of cell cycle related protein, such as cyclin B1, cdc2, and p-cdc2 (T14). Meanwhile, YSY-01A could inhibit the TNF-α-induced NF-κB nuclear translocation and lead to the increase of IκBα as well as the decrease of IKK and Gadd45α. In conclusion, YSY-01A showed remarkable anti-cancer activity on SK-OV-3 cells, and its molecular mechanisms were related to G2/M cell cycle arrest. 相似文献
992.
993.
背景:目前国外有很多脊柱侧凸方面的有限元研究,均是在建立良好的有限元脊柱侧凸模型基础上进行的,但是国内尚未有建立脊柱侧凸有限元模型的报道。
目的:利用有限元分析软件abaqus建立青少年特发性脊柱侧弯三维实体有限元模型。
设计、时间及地点:三维有限元建模,于2007-08/2008-05在北京协和医院生物力学实验室完成。
对象:经北京协和医院选取女性志愿者1名,17岁,发现脊柱侧凸4年,为双弯畸形。上弯为胸弯,下弯为腰弯,Risser征Ⅳ度。
方法:获得青少年特发性脊柱侧弯患者的CT资料,导入医学建模软件mimics11.11,获得医学仿真模型。利用获得青少年特发性脊柱侧弯患者医学仿真模型,导入有限元分析软件abaqus6.7,通过表面网格体网格化、定义材质属性、定义接触、定义连接、模拟韧带等建立PUMCⅡdⅡ型青少年特发性脊柱侧弯患者有限元分析模型。
主要观察指标:建立模型的节点和单元数、韧带的弹簧单元模拟数目、表面接触数目。
结果:建立的特发性脊柱侧弯有限元模型,共包含节点数:648 034,单元数:3 074 881,单元类型为C3D4,为一阶单元,共计定义表面224个,表面间接触34对,表面间绑定78对(tie接触),定义弹簧单元162个。
结论:利用计算机软件abaqus成功地建立特发性脊柱侧弯的有限元模型,具有良好的仿生效果及生物逼真度。 相似文献
994.
995.
Regulation of glucose transport and insulin signaling by troglitazone or metformin in adipose tissue of type 2 diabetic subjects. 总被引:11,自引:0,他引:11
Theodore P Ciaraldi Alice P S Kong Neelima V Chu Dennis D Kim Sunita Baxi Mattias Loviscach Ray Plodkowski Richard Reitz Michael Caulfield Sunder Mudaliar Robert R Henry 《Diabetes》2002,51(1):30-36
Type 2 diabetic subjects failing glyburide therapy were randomized to receive additional therapy with either metformin (2,550 mg/day) or troglitazone (600 mg/day) for 3-4 months. Biopsies of subcutaneous abdominal adipose tissue were obtained before and after therapy. Glycemic control was similar with both treatments. Metformin treatment increased insulin-stimulated whole-body glucose disposal rates by 20% (P < 0.05); the response to troglitazone was greater (44% increase, P < 0.01 vs. baseline, P < 0.05 vs. metformin). Troglitazone-treated subjects displayed a tendency toward weight gain (5 +/- 2 kg, P < 0.05), increased adipocyte size, and increased serum leptin levels. Metformin-treated subjects were weight-stable, with unchanged leptin levels and reduced adipocyte size (to 84 +/- 4% of control, P < 0.005). Glucose transport in isolated adipocytes from metformin-treated subjects was unaltered from pretreatment. Glucose transport in both the absence (321 +/- 134% of pre-Rx, P < 0.05) and presence of insulin (418 +/- 161%, P < 0.05) was elevated after troglitazone treatment. Metformin treatment had no effect on adipocyte content of GLUT1 or GLUT4 proteins. After troglitazone treatment, GLUT4 protein expression was increased twofold (202 +/- 42%, P < 0.05). Insulin-stimulated serine phosphorylation of Akt was augmented after troglitazone (170 +/- 34% of pre-Rx response, P < 0.05) treatment and unchanged by metformin. We conclude that the ability of troglitazone to upregulate adipocyte glucose transport, GLUT4 expression, and insulin signaling can contribute to its greater effect on whole-body glucose disposal. 相似文献
996.
Jing Zhang Jun-Jie Xu Zhen-Xing Chu Qing-Hai Hu Xiao-Xu Han Bin Zhao Yong-Jun Jiang Wen-Qing Geng Hong Shang 《中华医学杂志(英文版)》2020,133(23):2778
Background:Human immunodeficiency virus (HIV) prevalence among student men who have sex with men (MSM) in college is more than 5.0% and keeps on increasing in China. This study aims to clarify the proportion of HIV recent infection, its propeller and the source among college student MSM.Methods:We conducted a multicenter cross-sectional study in seven major Chinese cities during 2012-2013. HIV recent infections (≤ 168 days) and incidence was measured and estimated by BED HIV-1 capture enzyme immunoassay (BED-CEIA) testing strategy. HIV-related behaviors and transmitted drug resistance (TDR) were investigated and compared between the college student MSM, <25-year-old non-student youth MSM (NSYM), and ≥25-year-old non-student non-youth MSM (NSNYM), using structured survey, and analyses of drug resistance.Results:Overall, 4,496 (4496/4526, 99.3%) were eligible for enrollment, comprising 565 college student MSM, 1,094 NSYM, and 2,837 NSNYM. The proportion of HIV recent infection were 70.3% (26/37), 50.8% (65/128) and 35.1% (95/271), the HIV incidence rate were 10.0 (95% CI: 6.2-13.9)/100PY, 12.9 (95% CI: 9.8-16.1)/100PY, 6.8 (95% CI: 5.4-8.2)/100PY, and TDR prevalence were 7.4% (2/27), 2.0%, (2/98) and 4.9% (11/226), among student MSM, NSYM, and NSNYM, respectively. Among HIV positive student MSM with age< 21-year-old, the proportion of HIV recent infection is 90.9% (10/11). Factors independently associated with HIV recent infection in student MSM was usage of recreational drug in the past 6 months (AOR: 2.5; 95% CI: 1.0–5.8).Conclusions:College student MSM had higher proportion of HIV recent infection and TDR than the youth and older MSM in China during 2012-2013. The HIV infections were more likely to happen during the early year of college life among student MSM. 相似文献
997.
Mohareb Amir M. Rosenberg Jacob M. Bhattacharyya Roby P. Kotton Camille N. Chu Jacqueline T. Jilg Nikolaus Hysell Kristen M. Albin John S. Sen Pritha Bloom Seth M. Schiff Abigail E. Zachary Kimon C. Letourneau Alyssa R. Kim Arthur Y. Hurtado Rocio M. 《Journal of immigrant and minority health / Center for Minority Public Health》2021,23(6):1343-1347
Journal of Immigrant and Minority Health - Immunomodulating therapies for COVID-19 may carry risks of reactivating latent infections in foreign-born people. We conducted a rapid review of... 相似文献
998.
Tsu‐Nai Wang Hsing‐I Tseng Ching‐Chu Kao Yu‐Te Chu Wu‐Yuan Chen Pei‐Fen Wu Chien‐Hung Lee Ying‐Chin Ko 《Pediatric allergy and immunology》2010,21(7):1064-1071
Wang T‐N, Tseng H‐I, Kao C‐C, Chu Y‐T, Chen W‐Y, Wu P‐F, Lee C‐H, Ko Y‐C. The effects of NOS1 gene on asthma and total IgE levels in Taiwanese children, and the interactions with environmental factors.Pediatr Allergy Immunol 2010: 21: 1064–1071.© 2010 John Wiley & Sons A/S Asthma is a complex disorder, which is known to be affected by interactions between genetic and environmental factors. The aim of this study was to investigate the three microsatellite polymorphisms of GT repeats in intron 2, AAT repeats in intron 20, and CA repeats in exon 29 of the NOS1 gene in 155 asthmatic children and 301 control children, and the interaction with environmental factors in southern Taiwan. Total serum IgE, phadiatop test and genetic polymorphisms were measured. The genotype frequency of 14/14‐AAT repeats of the NOS1 gene was significantly higher in the asthmatic group (p = 0.01). Total IgE concentrations were higher in asthmatic children (p = 0.015) carrying the NOS1 14/14‐AAT genotype than in subjects with other polymorphisms. The gene and environmental interaction effects were 3.83‐fold, 6.86‐fold, and 8.04‐fold (all corrected p‐values <0.001) between subjects carrying at least one NOS1 14‐AAT allele and exposure to cockroaches, high levels of total IgE, and positive response against the phadiatop test in asthmatic children. The findings of this study provide strong evidence that NOS1 gene with 14‐AAT tandem repeats has a significant effect in asthmatic children. Environmental factors and atopic status will enhance the asthmatic risk for children who carry NOS1 susceptible allele. 相似文献
999.
目的研究中性粒细胞与淋巴细胞比值(NLR)及血小板与淋巴细胞比值(PLR)在重症肺炎支原体肺炎(MPP)中的诊断价值。方法回顾性分析2015年1月至2017年12月苏州大学附属儿童医院住院的616例MPP患儿(MPP组)的临床资料和实验室数据,选取同期100例健康体检儿童为健康对照组。采用t检验或秩和检验比较MPP组与健康对照组、重症MPP组与普通MPP组间的NLR及PLR的差异。筛选出影响重症MPP的危险因素,描绘受试者工作特征曲线(ROC)并寻找最佳截断点。结果1.MPP组患儿白细胞计数(WBC)、中性粒细胞数(N)、血小板计数(PLT)、NLR、PLR、免疫球蛋白(Ig)M的中位数及CD3^(-)CD_(19)^(+)、CD_(19)^(+)CD_(23)^(+)百分比的中位数均高于健康对照组[8.36×10^(9)/L比7.49×10^(9)/L、4.41×10^(9)/L比3.11×10^(9)/L、340.92×10^(9)/L比234.00×10^(9)/L、1.70比0.91、112.99比70.34、1.33 g/L比1.29 g/L、20.95%比17.10%、11.25%比9.70%];淋巴细胞数(L)、IgA的中位数及CD3^(+)、CD3^(+)CD8^(+)、CD3^(-)CD_((16+56))^(+)百分比的中位数均低于健康对照组[2.64×10^(9)/L比3.37×10^(9)/L、0.86 g/L比1.30 g/L、64.55%比68.00%、23.65%比24.90%、10.50%比12.20%],差异均有统计学意义(Z=-3.074、-2.413、-2.972、-1.357、-1.863、-2.251、-4.282、-3.420、-2.221、-4.181、-2.784、-2.024、-2.791,均P<0.05)。2.重症MPP组患儿N、NLR、PLR、IgA、IgG、IgM的中位数及CD3^(+)、CD3^(+)CD8^(+)百分比均高于普通MPP组[5.18×10^(9)/L比3.52×10^(9)/L、2.39比1.03、149.32比94.23、1.29 g/L比0.71 g/L、9.63 g/L比8.19 g/L、1.40 g/L比1.29 g/L、(65.53±9.75)%比(62.81±9.89)%、(25.35±6.65)%比(23.38±6.91)%];L的中位数、CD3^(-)CD_(19)^(+)、CD_(19)^(+)CD_(23)^(+)百分比的中位数均低于普通MPP组(2.02×10^(9)/L比3.25×10^(9)/L、17.40%比21.50%、9.00%比11.70%),差异均有统计学意义(Z/t=-7.807、-11.313、-10.452、-8.819、-6.162、-3.047、-3.128、-3.270、-9.402、-5.191、-5.214,均P<0.05)。3.通过单因素和多因素的Logistic回归分析发现,CD3^(-)CD_(19)^(+)是患儿发生重症MPP的保护因素;N、NLR、PLR是患重症MPP的危险因素(均P<0.05),且相对危险度由高到低依次为NLR>PLR>N。4.NLR、PLR诊断重症MPP的ROC曲线下面积(AUC)分别为:NLR(AUC=0.789,95%CI:0.754~0.823,P<0.001);PLR(AUC=0.767,95%CI:0.730~0.804,P<0.001)。当NLR的截断值为1.09时,敏感性为98.9%,特异性为70.6%;当PLR的截断值为97.47时,敏感性为88.5%,特异性为69.4%。结论NLR、PLR可作为发生重症MPP的独立影响因素,对诊断重症MPP有一定价值。 相似文献
1000.
Derek K. Chu Romina Brignardello-Petersen Gordon H. Guyatt Cristian Ricci Jon Genuneit 《Pediatric allergy and immunology》2022,33(1):e13609
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care. 相似文献