全文获取类型
收费全文 | 1962篇 |
免费 | 116篇 |
国内免费 | 23篇 |
专业分类
电工技术 | 24篇 |
综合类 | 61篇 |
化学工业 | 361篇 |
金属工艺 | 73篇 |
机械仪表 | 57篇 |
建筑科学 | 101篇 |
矿业工程 | 27篇 |
能源动力 | 47篇 |
轻工业 | 277篇 |
水利工程 | 15篇 |
石油天然气 | 47篇 |
武器工业 | 1篇 |
无线电 | 128篇 |
一般工业技术 | 356篇 |
冶金工业 | 257篇 |
原子能技术 | 23篇 |
自动化技术 | 246篇 |
出版年
2024年 | 6篇 |
2023年 | 18篇 |
2022年 | 37篇 |
2021年 | 64篇 |
2020年 | 45篇 |
2019年 | 52篇 |
2018年 | 78篇 |
2017年 | 67篇 |
2016年 | 84篇 |
2015年 | 62篇 |
2014年 | 76篇 |
2013年 | 169篇 |
2012年 | 114篇 |
2011年 | 160篇 |
2010年 | 109篇 |
2009年 | 87篇 |
2008年 | 94篇 |
2007年 | 73篇 |
2006年 | 64篇 |
2005年 | 59篇 |
2004年 | 51篇 |
2003年 | 46篇 |
2002年 | 43篇 |
2001年 | 16篇 |
2000年 | 34篇 |
1999年 | 45篇 |
1998年 | 65篇 |
1997年 | 43篇 |
1996年 | 27篇 |
1995年 | 39篇 |
1994年 | 23篇 |
1993年 | 15篇 |
1992年 | 8篇 |
1991年 | 10篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 9篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 13篇 |
1974年 | 5篇 |
1973年 | 3篇 |
1972年 | 5篇 |
排序方式: 共有2101条查询结果,搜索用时 18 毫秒
1.
2.
Deniz Caylioglu Rieke Johanna Meyer Dana Hellmold Carolin Kubelt Michael Synowitz Janka Held-Feindt 《International journal of molecular sciences》2021,22(7)
Glioblastoma (GBM) is a barely treatable disease due to its profound chemoresistance. A distinct inter- and intratumoral heterogeneity reflected by specialized microenvironmental niches and different tumor cell subpopulations allows GBMs to evade therapy regimens. Thus, there is an urgent need to develop alternative treatment strategies. A promising candidate for the treatment of GBMs is AT101, the R(-) enantiomer of gossypol. The present study evaluates the effects of AT101, alone or in combination with temozolomide (TMZ), in a microenvironmental glioma stem cell niche model of two GBM cell lines (U251MG and U87MG). AT101 was found to induce strong cytotoxic effects on U251MG and U87MG stem-like cells in comparison to the respective native cells. Moreover, a higher sensitivity against treatment with AT101 was observed upon incubation of native cells with a stem-like cell-conditioned medium. This higher sensitivity was reflected by a specific inhibitory influence on the p-p42/44 signaling pathway. Further, the expression of CXCR7 and the interleukin-6 receptor was significantly regulated upon these stimulatory conditions. Since tumor stem-like cells are known to mediate the development of tumor recurrences and were observed to strongly respond to the AT101 treatment, this might represent a promising approach to prevent the development of GBM recurrences. 相似文献
3.
4.
5.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time. 相似文献
6.
Guo Haitao Qiao Weihong Ba Yan Li Zongshi Jin Kun Peng Qinji 《Petroleum Science and Technology》2006,24(1):51-60
The GC/MS and NMR analysis of the reaction products of naphthalene with 1-bromohexane were reported. The products obtained were suggested to have six isomers of linear hexylnaphthalene and the structure of each isomer was determined by GC/MS and NMR spectra. For the first time, the unique chemical shift data were obtained. The content of each isomer calculated by 1H NMR and 13C NMR spectra was consistent with that by GC/MS spectra, which confirmed the accuracy of NMR data. 相似文献
7.
8.
AG Labetskaia KM Kireenko IV Ba?dakova IM Tishechkina 《Canadian Metallurgical Quarterly》1997,31(5):391-396
The study of the micromammalian parasite complexes in the Belorussian part of the evacuation zone of the Chernobyl nuclear station revealed 13 species of Coccidia and 30 species of ectoparasitic Arthropoda. Total increase of abundance and biodiversity of both parasites and their hosts was observed. The part of ectoparasites being epidemically hazardous was significantly increased. An analysis of a long-term dynamics of parasite abundance reveals their adaptation to new conditions in the Belorussia. 相似文献
9.
II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
10.