全文获取类型
收费全文 | 772篇 |
免费 | 114篇 |
国内免费 | 11篇 |
专业分类
综合类 | 16篇 |
化学工业 | 484篇 |
金属工艺 | 23篇 |
机械仪表 | 20篇 |
建筑科学 | 4篇 |
轻工业 | 151篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 7篇 |
一般工业技术 | 176篇 |
冶金工业 | 10篇 |
原子能技术 | 1篇 |
自动化技术 | 3篇 |
出版年
2024年 | 5篇 |
2023年 | 10篇 |
2022年 | 79篇 |
2021年 | 114篇 |
2020年 | 41篇 |
2019年 | 61篇 |
2018年 | 48篇 |
2017年 | 48篇 |
2016年 | 48篇 |
2015年 | 32篇 |
2014年 | 51篇 |
2013年 | 64篇 |
2012年 | 60篇 |
2011年 | 53篇 |
2010年 | 47篇 |
2009年 | 34篇 |
2008年 | 23篇 |
2007年 | 21篇 |
2006年 | 12篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1986年 | 3篇 |
1982年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有897条查询结果,搜索用时 687 毫秒
141.
Yufang Zhu Toshiyuki Ikoma Nobutaka Hanagata Stefan Kaskel 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(3):471-478
Rattle‐type Fe3O4@SiO2 hollow mesoporous spheres with different particle sizes, different mesoporous shell thicknesses, and different levels of Fe3O4 content are prepared by using carbon spheres as templates. The effects of particle size and concentration of Fe3O4@SiO2 hollow mesoporous spheres on cell uptake and their in vitro cytotoxicity to HeLa cells are evaluated. The spheres exhibit relatively fast cell uptake. Concentrations of up to 150 µg mL?1 show no cytotoxicity, whereas a concentration of 200 µg mL?1 shows a small amount of cytotoxicity after 48 h of incubation. Doxorubicin hydrochloride (DOX), an anticancer drug, is loaded into the Fe3O4@SiO2 hollow mesoporous spheres, and the DOX‐loaded spheres exhibit a somewhat higher cytotoxicity than free DOX. These results indicate the potential of Fe3O4@SiO2 hollow mesoporous spheres for drug loading and delivery into cancer cells to induce cell death. 相似文献
142.
Inhibition of influenza virus infection by multivalent sialic-acid-functionalized gold nanoparticles
Papp I Sieben C Ludwig K Roskamp M Böttcher C Schlecht S Herrmann A Haag R 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(24):2900-2906
An efficient synthesis of sialic-acid-terminated glycerol dendron to chemically functionalize 2 nm and 14 nm gold nanoparticles (AuNPs) is described. These nanoparticles are highly stable and show high activity towards the inhibition of influenza virus infection. As the binding of the viral fusion protein hemagglutinin to the host cell surface is mediated by sialic acid receptors, a multivalent interaction with sialic-acid-functionalized AuNPs is expected to competitively inhibit viral infection. Electron microscopy techniques and biochemical analysis show a high binding affinity of the 14 nm AuNPs to hemagglutinin on the virus surface and, less efficiently, to isolated hemagglutinin. The functionalized AuNPs are nontoxic to the cells under the conditions studied. This approach allows a new type of molecular-imaging activity-correlation and is of particular relevance for further application in alternative antiviral therapy. 相似文献
143.
144.
This paper reports about cotton textile modification by sol-gel technology with the purpose of obtaining antibacterial properties, evaluation of antibacterial properties and dermal toxicity tests of cotton textile with Zn and Si coating. Antibacterial properties evaluation against pathogenic microorganisms Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli made using the Parallel streak method in accordance with ATCC147 standard. For more specific evaluation of the coated textile, in vitro cytotoxicity test with epidermal HaCat cells was done. It is concluded that the coatings containing Zn and Si obtained by the sol-gel technology can impart antibacterial properties against pathogenic bacteria to the textile by preventing the bacteria from growing; strong inhibition of growth was detected for all test microorganisms. Based on the dermal toxicity test results, it is not expected that the prolonged contact of the skin with coated textiles will have a negative impact on the skin tissue – epidermis. 相似文献
145.
146.
利用漆酶、辣根过氧化物酶在均相和非均相反应体系中催化壳聚糖与没食子酸反应,以增强壳聚糖的抗氧化性。研究酶种类、反应体系p H值、反应温度、反应时间、酶用量和底物的质量比等因素对产物接枝率的影响。利用单因素试验和正交试验确定的最适反应条件为反应p H 4.5、反应温度25℃、反应时间5 h、没食子酸与壳聚糖的质量比3∶1、漆酶用量4 U,此条件下衍生物的接枝率为65.2%。对衍生物分别进行体外抗氧化活性和细胞毒性检测,结果表明,在相同添加量的情况下,衍生物的抗氧化性显著高于未改性的壳聚糖,而且产物无细胞毒性。 相似文献
147.
148.
The Mediterranean Diet decreases LDL atherogenicity in high cardiovascular risk individuals: a randomized controlled trial
下载免费PDF全文
![点击此处可从《Molecular nutrition & food research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Álvaro Hernáez Olga Castañer Alberto Goday Emilio Ros Xavier Pintó Ramón Estruch Jordi Salas‐Salvadó Dolores Corella Fernando Arós Lluis Serra‐Majem Miguel Ángel Martínez‐González Miquel Fiol José Lapetra Rafael de la Torre M. Carmen López‐Sabater Montserrat Fitó 《Molecular nutrition & food research》2017,61(9)
149.
Yu Pan Annika Leifert Michael Graf Frank Schiefer Sven Thoröe‐Boveleth Janine Broda Mary C. Halloran Henner Hollert Dominic Laaf Ulrich Simon Willi Jahnen‐Dechent 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(6):863-869
Gold nanoparticles (AuNP) show great potential for diagnostic and therapeutic application in humans. A great number of studies have tested the cytotoxicity of AuNP using cell culture. There is, however, an urgent need to test AuNP in vertebrate animal models that interrogate biodistribution and complex biological traits like organ development, whole body metabolism, and cognitive function. The sheer number of different compounds precludes the use of small rodent model for initial screening. The extended fish embryo test (FET) is used here to bridge the gap between cell culture and small animal models. A study on the toxicity of ultrasmall AuNP in wild type and transgenic zebrafish is presented. FET faithfully reproduce all important findings of a previous study in HeLa cells and add new important information on teratogenicity and hepatotoxicity that could not be gained from studying cultured cells. 相似文献
150.
采用十六烷基三甲基溴化铵(CTAB)作为表面活性剂修饰羧基化的单壁碳纳米管(SWNT-COOH/CTAB),并对原始单壁碳纳米管(SWNTs)与羧基化修饰的单壁碳纳米管(SWNT-COOH)进行材料学特征比较。通过细胞活力和细胞凋亡实验对SWNTs、SWNT-COOH和SWNT-COOH/CTAB的细胞毒性进行比较。结果表明,羧基化修饰的单壁碳纳米管比原始单壁碳纳米管的毒性小,单壁碳纳米管经羧基化后其毒性降低;浓度及时间曲线显示SWNT-COOH/CTAB的毒性与表面活性剂CTAB相关,CTAB和 SWNT-COOH/CTAB的细胞毒性在低浓度范围内(0.5-25μg/mL)是可接受的。十六烷基三甲基溴化铵修饰的羧基化单壁碳纳米管在低浓度范围(0.5-25μg/mL)内可以较安全地用于生物医学领域。 相似文献