全文获取类型
收费全文 | 1989篇 |
免费 | 378篇 |
国内免费 | 214篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 4篇 |
妇产科学 | 17篇 |
基础医学 | 120篇 |
口腔科学 | 21篇 |
临床医学 | 155篇 |
内科学 | 149篇 |
皮肤病学 | 29篇 |
神经病学 | 62篇 |
特种医学 | 15篇 |
外科学 | 47篇 |
综合类 | 144篇 |
预防医学 | 103篇 |
眼科学 | 14篇 |
药学 | 1077篇 |
中国医学 | 553篇 |
肿瘤学 | 67篇 |
出版年
2024年 | 3篇 |
2023年 | 104篇 |
2022年 | 112篇 |
2021年 | 108篇 |
2020年 | 120篇 |
2019年 | 86篇 |
2018年 | 75篇 |
2017年 | 73篇 |
2016年 | 89篇 |
2015年 | 114篇 |
2014年 | 165篇 |
2013年 | 183篇 |
2012年 | 180篇 |
2011年 | 160篇 |
2010年 | 126篇 |
2009年 | 104篇 |
2008年 | 111篇 |
2007年 | 166篇 |
2006年 | 133篇 |
2005年 | 97篇 |
2004年 | 60篇 |
2003年 | 46篇 |
2002年 | 35篇 |
2001年 | 32篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1998年 | 14篇 |
1997年 | 9篇 |
1996年 | 13篇 |
1995年 | 16篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 1篇 |
排序方式: 共有2581条查询结果,搜索用时 46 毫秒
61.
《Clinical therapeutics》2021,43(7):1272-1277
The cost of insulin has increased exponentially since its discovery in the 1920s, but the degree to which this financial burden has been transferred to patients is unknown. The present study is a retrospective analysis using claims data for privately insured patients with type 1 diabetes from 2005 to 2017. We quantify the mean annual out-of-pocket costs for insulin and diabetes-related supplies during the study period. It is imperative for health care professionals to be aware of this cost, and we hope that these findings serve as a call for legislation to cap the rising price of insulin. 相似文献
62.
ObjectiveCognitive impairment is a common neurological disease of which NLRP3-related neuroinflammation has been demonstrated to be an essential mediator. Previous studies have indicated that long non-coding RNAs (lncRNAs) are critical for the development of neurological disorders. However, the roles and functions of lncRNA 4344 in neuroinflammation during cognitive impairment are unknown and need to be further elucidated.MethodsLipopolysaccharide (LPS)-induced rat cognitive impairment and rat microglia (RM) cell inflammation models were established in vitro and in vivo. The Morris water maze test was used to evaluate the cognitive behavior of the rats. Gene expression was assessed using real-time quantitative polymerase chain reaction, and protein levels using enzyme-linked immunosorbent assay, or western blot analysis. The targeting relationship between lncRNA 4344, miR-138-5p, and NLRP3 was identified using bioinformatics analysis and a dual-luciferase reporter gene assay. Hematoxylin-Eosin and Nissl stainings, terminal deoxynucleotidyl transferase dUTP nick end labeling, or immunofluorescence staining assays were performed to detect pathological changes, neuronal apoptosis, or positive cells in hippocampal tissues, respectively.ResultsThe expression levels of lncRNA 4344 and NLRP3 were upregulated in the hippocampal tissues of LPS-treated rats and RM cells, and showed a strong positive correlation between each other. LncRNA 4344 overexpression further enhanced the expression of NLRP3 and its downstream genes (caspase-1, IL-1β, and IL-18), as well as neuronal apoptosis in LPS-stimulated RM cells, whereas lncRNA 4344 silencing attenuated the inflammatory injuries. Moreover, miR-138-5p was the direct target of lncRNA 4344 and was downregulated in the RM cell inflammation model. We also found that miR-138-5p directly reduced the expression of NLRP3 and its downstream genes. Subsequently, the results of the animal experiments showed that the lncRNA 4344/miR-138-5p/NLRP3 axis plays an essential role in regulating the cognitive behavior, pathological changes and apoptosis of hippocampal neurons, expression of inflammation-related factors (NLRP3, caspase-1, IL-1β, and IL-18), and microglial activation in LPS-induced cognitive impairment rats.ConclusionOur results demonstrated for the first time that lncRNA 4344 regulates NLRP3-related neuroinflammation and cognitive impairment by targeting miR-138-5p, providing a possible target for the treatment of diseases characterized by a cognitive deficit. 相似文献
63.
Li Yanzhen Zhang Hong Yang Jingwen Zhan Muouyang Hu Xuefei Liu Yongmin Yu Lingling Yan Xiaochen Liang Shangdong Zhang Ruyue Lu Ying Li Beining Liu Cunzhi Li Man 《Chinese medicine》2021,16(1):1-15
Dried fruits of Psoralea corylifolia L. (Psoraleae Fructus) is one of the most popular traditional Chinese medicine with treatment for nephritis, spermatorrhea, pollakiuria, asthma, and various inflammatory diseases. Bakuchiol is main meroterpenoid with bioactive diversity from Psoraleae Fructus. This study was designed to seek structural diverse bakuchiol derivants with anti-inflammatory activities from this plant. Various column chromatography methods were used for isolation experiment. Structures and configurations of these compounds were determined by spectroscopic methods and single-crystal X-ray diffraction. Their inhibition on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were evaluated by the Griess reaction.
Twelve unpresented bakuchiol dimmers, bisbakuchiols M–U (1–9) and bisbakuchiol ethers A–C (10–12), along with five known compounds (13–17), were isolated from the fruits of Psoralea corylifolia L. Compounds 1–3, 10–12, 16 and 17 exhibited inhibitory activities against LPS-induced NO production in RAW264.7 macrophages, and the inhibition of compound 1 (half maximal inhibitory concentration (IC50) value = 11.47 ± 1.57 μM) was equal to that of L-N(6)-(1-iminoethyl)-lysine (IC50 = 10.29 ± 1.10 μM) as a positive control. Some compounds exhibited inhibitory activities against NO production, and the study of structure–activity relationship suggested that uncyclized compounds with oxygen substitution at C-12/12′ showed strong inhibitory activities, and carbonyl units contributed to enhanced activities. 相似文献
64.
Batsukh Zolboo Toume Kazufumi Javzan Batkhuu Kazuma Kohei Cai Shao-Qing Hayashi Shigeki Kawahara Nobuo Maruyama Takuro Komatsu Katsuko 《Journal of natural medicines》2020,74(1):170-188
Journal of Natural Medicines - Saposhnikoviae Radix (SR) is a commonly used crude drug that is obtained from the root and rhizome of Saposhnikovia divaricata which is distributed throughout China,... 相似文献
65.
67.
68.
目的:改进光磁双模态分子探针钆-[4,7-双-羧甲基-10-(2-荧光素硫脲乙基)-1,4,7,10-四氮杂环十二烷-1-基]-乙酸络合物(Gd-DO3A-EA-FITC)的合成及纯化方法。方法:1,4,7,10-四氮杂环十二烷(DOTA)经过取代反应、水解反应、偶联反应、与金属络合反应,合成Gd-DO3A-EA-FITC。结果:改进了Gd-DO3A-EA-FITC的合成路线,分别通过取代反应、水解反应、偶联反应、络合反应得到了光磁双模态分子探针,该反应总收率为34.6%,与原路线(18.0%)相比,总收率增加,各化合物通过核磁共振氢谱、核磁共振碳谱和质谱分析法鉴定后结果正确。改进后的路线避免了取代反应不易控制的缺点,且在纯化分离方面,将载样量少、成本高的制备型高效液相色谱纯化改进为载样量多、简便易操作的柱色谱。结论:改进后的路线改善了反应条件的可控性,并且使化合物纯化分离过程变得更加简易,同时使总收率明显提升。光磁双模态探针可同时将活体磁共振成像与离体光学成像相结合,实现光磁双重同步检测,使二者的检测结果相互验证。可将光磁双模态分子探针应用于脑结构及其功能相关研究,并且经静脉途径给药后可以对脑肿瘤进行研究,因此在脑肿瘤和脑血管相关疾病的药物治疗中能够发挥重要的作用。 相似文献
69.
目的 考察包载多西他赛的聚合物胶束抑制小鼠乳腺癌转移效果。方法 采用薄膜分散法制备两种包载多西他赛(docetaxel,DTX)的聚合物胶束:普通胶束(DSPE-mPEG2000-Micelles,DM)和含聚乙二醇维生素E琥珀酸酯(D-α-tocopheryl polyethylene glycol 1000 succinate,TPGS1000)的聚合物胶束(TPGS1000/DSPE-mPEG2000-Micelles,TDM)。评价胶束包封率、载药量、粒径和zeta电位。采用尾静脉注射4T1/Luc细胞建立小鼠肺转移模型,评价胶束治疗后的肺部肿瘤生物发光强度和结节数量。结果 所制备的载多西他赛聚合物胶束包封率>85%,载药量约为3%,粒径约为20 nm,zeta电位约为 -4 mV,且TDM包封率和载药量更高,粒径更小。两种聚合物胶束均可降低乳腺癌肺转移模型小鼠肺部肿瘤生物发光强度、减少肺部结节数量,且TDM作用更强。结论 含TPGS1000的包载多西他赛的聚合物胶束TDM具有较好的抑制小鼠乳腺癌转移的作用。 相似文献
70.