全文获取类型
收费全文 | 275355篇 |
免费 | 15498篇 |
国内免费 | 8058篇 |
专业分类
耳鼻咽喉 | 3391篇 |
儿科学 | 9937篇 |
妇产科学 | 3961篇 |
基础医学 | 20211篇 |
口腔科学 | 4863篇 |
临床医学 | 35014篇 |
内科学 | 50143篇 |
皮肤病学 | 3538篇 |
神经病学 | 12294篇 |
特种医学 | 15403篇 |
外国民族医学 | 22篇 |
外科学 | 39715篇 |
综合类 | 30072篇 |
现状与发展 | 27篇 |
一般理论 | 1篇 |
预防医学 | 17392篇 |
眼科学 | 4855篇 |
药学 | 27958篇 |
113篇 | |
中国医学 | 6485篇 |
肿瘤学 | 13516篇 |
出版年
2023年 | 2642篇 |
2022年 | 5671篇 |
2021年 | 12246篇 |
2020年 | 7301篇 |
2019年 | 12748篇 |
2018年 | 7537篇 |
2017年 | 6814篇 |
2016年 | 8710篇 |
2015年 | 11658篇 |
2014年 | 21435篇 |
2013年 | 19008篇 |
2012年 | 22404篇 |
2011年 | 19431篇 |
2010年 | 17757篇 |
2009年 | 17055篇 |
2008年 | 15560篇 |
2007年 | 15570篇 |
2006年 | 13288篇 |
2005年 | 9116篇 |
2004年 | 5224篇 |
2003年 | 4519篇 |
2002年 | 3745篇 |
2001年 | 3076篇 |
2000年 | 2617篇 |
1999年 | 1869篇 |
1998年 | 2171篇 |
1997年 | 1903篇 |
1996年 | 1564篇 |
1995年 | 1535篇 |
1994年 | 1482篇 |
1993年 | 1110篇 |
1992年 | 1314篇 |
1991年 | 1154篇 |
1990年 | 1189篇 |
1989年 | 1145篇 |
1988年 | 1067篇 |
1987年 | 967篇 |
1986年 | 816篇 |
1985年 | 1718篇 |
1984年 | 1843篇 |
1983年 | 1325篇 |
1982年 | 1454篇 |
1981年 | 1404篇 |
1980年 | 1205篇 |
1979年 | 1039篇 |
1978年 | 835篇 |
1977年 | 801篇 |
1976年 | 717篇 |
1975年 | 467篇 |
1974年 | 488篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
21.
22.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。 相似文献
23.
《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases. 相似文献
24.
25.
26.
Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria. 相似文献
28.
29.
30.
目的探讨儿童期创伤与抑郁特质之间的中介和调节机制,为开展相关研究和干预提供参考。方法2017-2018年采用整群抽样的方法,抽取湖南某高校大一年级2 786名学生完成儿童期创伤问卷、状态特质抑郁问卷、自动思维问卷和特质应对方式问卷的调查。结果儿童期创伤、自动思维和消极应对对抑郁特质起正向的预测作用,积极应对对抑郁特质起负向的预测作用(β值分别为0.12,0.43,0.14,-0.33,P值均<0.05)。自动思维中介儿童期创伤与抑郁特质之间的关系(Bootstrapping法的95%CI为0.03~0.06)。消极应对分别调节了儿童期创伤与自动思维和儿童期创伤与抑郁特质之间的关系(P值均<0.05)。结论儿童期创伤影响抑郁特质,其关系受到应对方式和自动思维的影响。 相似文献