首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   707464篇
  免费   54313篇
  国内免费   17535篇
耳鼻咽喉   6861篇
儿科学   20781篇
妇产科学   10658篇
基础医学   58477篇
口腔科学   16258篇
临床医学   77848篇
内科学   115751篇
皮肤病学   9113篇
神经病学   54448篇
特种医学   20356篇
外国民族医学   48篇
外科学   68643篇
综合类   99897篇
现状与发展   61篇
一般理论   57篇
预防医学   75347篇
眼科学   10513篇
药学   61418篇
  1029篇
中国医学   44942篇
肿瘤学   26806篇
  2023年   11933篇
  2022年   17288篇
  2021年   30740篇
  2020年   30154篇
  2019年   32917篇
  2018年   31085篇
  2017年   27666篇
  2016年   25288篇
  2015年   23874篇
  2014年   46174篇
  2013年   50454篇
  2012年   39813篇
  2011年   42436篇
  2010年   33650篇
  2009年   31351篇
  2008年   30825篇
  2007年   30855篇
  2006年   27199篇
  2005年   23155篇
  2004年   19063篇
  2003年   16564篇
  2002年   13580篇
  2001年   12134篇
  2000年   9946篇
  1999年   8558篇
  1998年   7434篇
  1997年   6776篇
  1996年   5341篇
  1995年   5493篇
  1994年   5192篇
  1993年   4262篇
  1992年   4162篇
  1991年   3632篇
  1990年   3073篇
  1989年   2704篇
  1988年   2533篇
  1987年   2232篇
  1986年   2018篇
  1985年   6225篇
  1984年   7255篇
  1983年   5257篇
  1982年   6087篇
  1981年   5451篇
  1980年   4635篇
  1979年   4446篇
  1978年   3744篇
  1977年   2903篇
  1976年   3396篇
  1975年   2448篇
  1974年   2130篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.  相似文献   
2.
熊磊教授以理脾为本,将治痰贯穿始终。根据小儿脾常不足、肾常虚、肝常有余的生理特点,癫痫发作期治疗主以涤痰开窍,辅以理气健脾,同时配合活血化瘀通窍与平肝息风潜阳。主要选方为柴芍温胆汤、天麻钩藤饮、桃红四物汤加减;缓解期则以补肾养肝为主,兼以健脾化痰,主要选方为杞菊地黄丸合定痫丸加减,取得较好临床疗效。  相似文献   
3.
4.
《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   
5.
6.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
7.
8.
9.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号