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1.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components. 相似文献
2.
目的建立环境水样中痕量铜的浊点萃取(cloud point extraction,CPE)-火焰原子吸收光谱(flame atomic absorption spectrometry,FAAS)测定法。方法样品在p H 9.5的条件下,加入0.4 ml的1 mmol/L 2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)溶液,0.1%氯化钙溶液0.1 ml,5%(W/V)Triton X-114溶液0.8 ml,40℃加热15 min后离心,采用火焰原子吸收光谱法进行检测。结果在2~240μg/L的线性范围内,所得回归方程为A=0.002 7c+0.024 6,r=0.995 8。以3倍信噪比计算,方法的检出限为0.62μg/L,富集倍数为36.58倍,平均加标回收率为96.28%~98.08%,RSD为1.67%~3.13%。结论该方法简单、灵敏,具有良好的重现性,适用于环境水样中痕量铜的测定。 相似文献
3.
《Health & place》2020
In this study we used a participatory research method, photovoice, to explore community perceptions about environmental health risks, community assets, and strengths in and around an urban, degraded watershed in Northwest Atlanta, Georgia. This watershed, formed by Proctor Creek, is a focal point for redevelopment and infrastructure investments for years to come. Using a community-based participatory research approach, 10 Proctor Creek residents (watershed researchers), and a university partner, engaged in data collection; participatory data analysis; internal discussions; translation of research findings into watershed restoration, community revitalization, remedial action, and policy solutions; and dissemination of results to fellow watershed residents, stakeholders, and decision makers. We present a conceptual model linking the watershed researchers' understanding of urban policies and practice in the Proctor Creek Watershed to environmental, neighborhood and housing conditions and their influence on health outcomes and quality of life. Engaging community members in defining their own community environmental health challenges and assets yielded the following primary themes: 1) threats to the natural environment, 2) built environment stressors that influence health, 3) blight and divestment of public resources, and 4) hope for the future. Residents’ vision for the future of the watershed - a restored creek, revitalized neighborhoods, and restored people - is fueled by a strong connection to history, memory, and sense of place. We demonstrate the value of local knowledge in identifying previously unaddressed environmental health risks in the Proctor Creek Watershed as well as solutions to reduce or eliminate them. 相似文献
4.
目的 分析tCGA数据库中肝内胆管癌(ICC)高通量测序数据,寻找其预后相关基因,构建风险模型,并研究其在ICC组织中表达及作用通路。方法 下载tCGA数据库中33例ICC组织和8例癌旁组织中的RNA-seq表达矩阵数据和患者临床资料信息,利用edgeR软件包进行基因差异表达分析,通过单因素Cox回归分析筛选出预后相关差异基因,对差异基因绘制生存曲线,筛选出具有临床意义的基因,经多因素Cox回归分析并构建风险模型,通过京都基因与基因组百科全书(KEGG)通路富集分析了解预后相关基因的作用通路。结果 通过edgeR分析后得到6 617个差异基因(筛选标准为|log2 Fold Change|>1,P<0.05),其中高表达组4 094个,低表达组2 523个。通过功能富集发现,这些基因主要集中在化学物致癌作用、药物代谢-细胞色素P450系统、细胞色素P450对异生物质的代谢影响以及视黄醇代谢通路。经单因素Cox回归、R软件“survival”包生存曲线分析显示,UCN2、CST1、PROS1、SLC35E4、PEMT五个基因对ICC患者预后存在显著性影响。通过多因素Cox回归分析,CST1、PEMT、PROS1构建的风险模型对ICC患者预后具有判断作用。结论 UCN2、CST1、PROS1、SLC35E4、PEMT基因可能成为ICC预后判断指标,为后续临床试验提供数据支持。 相似文献
5.
BRIAN J. STOCKMAN CAROL A. BANNOW ROBERT M. MICELI MICHAEL E. DEGRAAF H. DAVID FISCHER CLARK W. SMITH 《Chemical biology & drug design》1995,45(1):11-16
Epitope libraries provide a method to identify peptide ligands for antibodies, receptors or other binding proteins. As such, they provide a powerful tool to rapidly identify lead ligands in the drug discovery process. In an attempt to correlate structural information with the results from peptide screening, we have used NMR spectroscopy of peptide/antibody complexes to demonstrate that core residues identified through a two-stage selection process undergo a larger structural change upon binding antibody than do positions in the peptide amenable to a variety of side chains. The model system used was the M2 monoclonal antibody/Flag? octapeptide epitope system. We have analyzed two peptides: Ac-Asp-Tyr-Lys-Leu-Gly-Asp-Asp-Leu-NH2 (peptide l), which contains several non-core positions randomized, and Ac-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Leu-NH2 (peptide 2), which closely corresponds to the original Flag? sequence. Enrichment of the peptides with 15N facilitated the investigation by permitting spectral editing of the peptide resonances in the presence of antibody. For peptide 1 the absolute shifts for the free vs. Fab-bound peptide were found to be largest for the amide groups of Asp-1 and Asp-6, in agreement with classification of these residues as critical by the phage display library selection process. For peptide 2 the largest absolute shifts were observed for Asp-1 and Asp-4, with the other aspartic acid residues also showing significant but smaller changes. © Munksgaard 1995. 相似文献
6.
本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。 相似文献
7.
化学品环境管理与水生实验动物 总被引:3,自引:1,他引:2
从分析化学品的特性入手,在概述化学品的环境管理对水生实验生物需求和国内外水生实验生物发展现状的基础上,从加强化学品环境管理的科学基础建设出发,对我国水生实验生物的研究与发展的标准化、产业化、必要的资质认可及信息交流提出建议。 相似文献
8.
目的观察PM2.5混悬液染尘大鼠的肺组织病理学改变及银染色显示肺内尘粒的效果。方法将收集的游离PM2.5制成混悬液,72只Wistar大鼠随机分为低剂量组(每0.2ml含PM2.50.3nag)、中剂量组(每0.2ml含PM2.50.75mg)、高剂量组(每0.2ml含PM2.52mg)和对照组,每组18只。3个实验组分别以不同的剂量采用支气管肺内滴入方式染尘,每周染尘1次。分别于染尘后第4、12及24周时,取肺脏,石蜡包埋组织切片进行HE染色及沃森一斯塔理(Worthin-Starry,WS)银染色观察、透射电镜(TEM)观察,对肺内尘粒进行X-线质谱元素分析(X-RSA)。计数大鼠肺内肉芽肿样病变的数目,测定肺内尘粒的沉积程度、平均积分吸光度值(IOD)和平均积分面密度值(IAD)。结果随着染毒时间的延长和染毒剂量的增大,大鼠肺内肉芽肿样病变的数目及其细胞质内尘粒的IAD值和IOD值也逐渐增高。这些尘粒在WS染色切片上呈黑褐色,更清晰;其IOD值和IAD值均明显高于HE染色下的测定值,差异有统计学意义(P〈0.05);尘粒IOD值与肉芽肿病变数目呈正相关关系(r=0.639,P〈0.01)。TEM下大鼠肺内尘粒的超微结构与游离的PM2.5相同,X-RSA分析两者的主要元素成分也相同,均为硅元素。结论PM2.5混悬液染尘可以引起大鼠肺内出现肉芽肿样病变,WS银染色方法可以较好地显示被吞噬细胞吞噬后的PM2.5,其染色效果优于HE染色。 相似文献
9.
目的 探讨富氧对高原人体运动心力储备方面的影响。方法 对海拔 3 70 0m高原的 1 2名健康青年富氧 (氧浓度为 2 4%~ 2 5 %)前后分别进行踏阶运动 ,采用心力监护仪采集和记录心动周期和心力信息 ,把完成规定运动量运动后第一心音 (S1 )幅值对安静时S1 幅值增加的相应倍数评估心肌收缩能力储备指数 (CCRI) ;利用舒张期和收缩期时限数据计算舒张期 /收缩期比值 (D/S比 )。结果 运动后较安静时HR ,D/S ,S1 幅值均增高 ,有非常显著性差异 (P <0 .0 1 ) ;富氧运动较未富氧运动CCRI,D/S ,S1 幅值增高 ,有显著性差异 (P <0 .0 5 ) ,HR无统计学意义 (P >0 .0 5 )。结论 高原低氧环境下心脏储备主要是心肌收缩能力储备而不是心率储备。富氧对增强机体心力储备具有重要作用 相似文献
10.
BACKGROUND: Since chronic infection with mucoid Pseudomonas aeruginosa (PA) is associated with deteriorating lung function, many parents of young children with cystic fibrosis (CF) fear the first PA positive throat swab as a milestone in the progression of the disease. To reduce the risk of PA acquisition from the environment, they perform preventive measures at home or outdoors. METHODS: In an attempt to evaluate the attitude of CF physicians towards these measures and the respective consulting practice, we mailed a questionnaire to all 65 certified paediatric CF centres in Germany. RESULTS: Physicians from 54 (83%) CF clinics replied. They expressed widely different ideas about the impact of the environment for the acquisition of P. aeruginosa, and recommended a large spectrum of preventive measures. Some physicians proposed only few precautions, which focussed on the prevention of cross-infection between patients, whereas others suggested prevention of any contact with moist or wet places, e.g. use different toothbrushes for mornings and evenings, or do without air-conditioning in the car. CONCLUSIONS: CF physicians have different opinions on the risk of PA acquisition from the environment. Doctors who recommend strict precautions could engender a parental fear of a ubiquous threat from invisible bacteria. The resulting extended safety measures might impair the family's quality of life. 相似文献