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991.
Zuopeng Zhang Huali Yang Ye Zhong Yueqing Wang Jian Wang Maosheng Cheng Yang Liu 《International journal of molecular sciences》2021,22(24)
Based on the strategy of the “tail approach”, 15 novel saccharide-modified sulfonamides were designed and synthesised. The novel compounds were evaluated as inhibitors of three human carbonic anhydrase (CA) isoforms, namely cytoplasmic CA II, transmembrane CA IX, and XII. Most of these compounds showed good activity against CAs and high topological polar surface area (TPSA) values, which had a positive effect on the selective inhibition of transmembrane isoforms CA IX and XII. In the in vitro activity studies, compounds 16a, 16b, and 16e reduced the viability of HT-29 and MDA-MB-231 cells with a high expression of CA IX under hypoxia. The inhibitory activity of compound 16e on the human osteosarcoma cell line MG-63 with a high expression of CA IX and XII was better than that of AZM. Moreover, high concentrations of compounds 16a and 16b reversed the acidification of the tumour microenvironment. In addition, compound 16a had a certain inhibitory effect on the migration of MDA-MB-231 cells. All the above results indicate that the saccharide-modified sulfonamide has further research value for the development of CA IX inhibitors. 相似文献
992.
Ni Made Pitri Susanti Sophi Damayanti Rahmana Emran Kartasasmita Daryono Hadi Tjahjono 《International journal of molecular sciences》2021,22(24)
The G1 phase of cell cycle progression is regulated by Cyclin-Dependent Kinase 4 (CDK4) as well as Cyclin-Dependent Kinase 6 (CDK6), and the acivities of these enzymes are regulated by the catalytic subunit, cyclin D. Cell cycle control through selective pharmacological inhibition of CDK4/6 has proven to be beneficial in the treatment of estrogen receptor-positive (ER-positive) breast cancer, particularly improving the progression-free survival of patients. Thus, targeting specific inhibition on CDK4/6 is bound to increase therapeutic efficiency. This study aimed to obtain CDK4/6 inhibitors through a pharmacophore-based virtual screening of the ZINC15 purchasable compound database using the in silico method. The pharmacophore model was designed based on the FDA-approved cdk4/6 inhibitor structures, and molecular docking was performed to further screen the hit compounds obtained. A total of eight compounds were selected based on docking results and interactions with CDK4 and CDK6, using palbociclib as the reference drug. According to the results, the compounds of ZINC585292724 and ZINC585291674 were the best compounds based on free binding energy, as well as hydrogen bond stability, and, therefore, exhibit potential as starting points in the development of CDK4/6 inhibitors. 相似文献
993.
分子动力学模拟的柔性对接 总被引:1,自引:1,他引:0
王亭 《计算机与应用化学》2007,24(1):91-93
分子自动对接技术在过去二十年里取得很大发展和成功,但是仍然面对如何处理分子柔性这样一个难题。这篇综述概要介绍分子柔性对接技术的进展并重点介绍分子动力学模拟技术。 相似文献
994.
微波交会对接雷达目标跟踪的卡尔曼滤波器设计 总被引:1,自引:0,他引:1
针对空间交会对接应用中追踪航天器对目标航天器的精密跟踪,采用三阶修正卡尔曼滤波器直接在球坐标系下对径向距离和径向速度进行联合跟踪,采用2个结构一致的二阶修正卡尔曼滤波器分别对俯仰角和俯仰角速度、方位角和方位角速度进行联合跟踪。提出一种状态噪声的实时估计算法,有效地解决了卡尔曼滤波应用中状态噪声的参数设计问题。仿真结果表明,本文设计的卡尔曼滤波器能够精确地跟踪目标航天器,同时具有较强的动态适应能力。 相似文献
995.
996.
Thermus thermophilus木糖异构酶复合物模型的建立与分析 总被引:1,自引:0,他引:1
Thermus thermophilus木糖异构酶在高果糖浆的工业生产及木糖发酵重组菌的构建方面具有极其广阔的应用前景.本文主要运用结构分析和分子对接及计算软件,确定了Mg~2及木糖异构酶天然底物D-木糖在1BXB晶体结构中的定位,构建出1BXB复合物模型并进行评价与分析.通过对1BXB复合物模型1与1XIC的结构进行比较,发现所构建模型中D-木糖周围的残基在木糖异构酶中高度保守,并且D-木糖的定位与取向与1XIC中底物分子基本一致. 相似文献
997.
航天器对接与捕获技术(Docking&capture technology,DCT)是实现航天器之间在轨连接、控制与分离,建立组合体间人员或资源交互的技术。对航天器对接与捕获技术的研究背景、发展历程、发展趋势、应用前景、技术内涵等内容进行了综述,首先从运载局限性催生对接技术发展、在轨服务需求爆发促进对接技术发展、空间碎片清理任务推动捕获技术发展等角度阐述了航天器对接与捕获技术的研究背景。从时间维度总结了该技术发展的三个历程,从技术途径角度概括了该技术的五个发展趋势。从在轨延寿、在轨手术、地外基建、轨道修正四个方面梳理了该技术的应用前景,提炼了该研究领域的八项关键技术。最后,给出了我国在该领域开展研究的方向和建议,为航天器在轨对接与捕获技术的未来研究提供参考。 相似文献
998.
999.
Mohd Sajid Ali Md Tabish Rehman Hamad Al-Lohedan Mohamed Fahad AlAjmi 《International journal of molecular sciences》2022,23(8)
The interaction of the important plasma protein, human serum albumin (HSA), with two monoterpenes found in cumin oil, i.e., cuminaldehyde (4-isopropylbenzaldehyde) and cuminol (4-isopropylbenzyl alcohol), was studied in this paper. Both experimental and computational methods were utilized to understand the mechanism of binding. The UV absorption profile of HSA changes in the presence of both cuminaldehyde and cuminol, due to the interaction between HSA with both monoterpenes. The intrinsic fluorescence intensity of HSA was also quenched on the sequential addition of both ligands, due to change in the microenvironment of the fluorophore present in the former. Quenching of HSA by cuminaldehyde was much higher in comparison to that in the presence of cuminol. Fluorescence quenching data were analyzed using modified Stern-Volmer and Lineweaver-Burk methods, which suggested that the binding mechanism was of a static type for both ligands. In both cases, the binding was favored by the domination of hydrophobic as well as hydrogen bonding/Van der Waals forces. Both ligands partially unfolded the secondary structure of HSA, although the effect of cuminaldehyde was more pronounced, as compared to cuminol. The preferred binding site of cuminaldehyde and cuminol inside HSA was also the same; namely, drug binding site 1, located in subdomain IIA. The study showed that cuminaldehyde binds strongly with albumin as compared to its alcohol counterpart, which is due to the more hydrophobic nature of the former. 相似文献
1000.
Duan S. Dimi Goran N. Kaluerovi Edina H. Avdovi Dejan A. Milenkovi Marko N.
ivanovi Ivan Poto
k Erika Samoov Milena S. Dimitrijevi Luciano Saso Zoran S. Markovi Jasmina M. Dimitri Markovi 《International journal of molecular sciences》2022,23(2)
In this contribution, four new compounds synthesized from 4-hydroxycoumarin and tyramine/octopamine/norepinephrine/3-methoxytyramine are characterized spectroscopically (IR and NMR), chromatographically (UHPLC-DAD), and structurally at the B3LYP/6-311++G*(d,p) level of theory. The crystal structure of the 4-hydroxycoumarin-octopamine derivative was solved and used as a starting geometry for structural optimization. Along with the previously obtained 4-hydroxycoumarin-dopamine derivative, the intramolecular interactions governing the stability of these compounds were quantified by NBO and QTAIM analyses. Condensed Fukui functions and the HOMO-LUMO gap were calculated and correlated with the number and position of OH groups in the structures. In vitro cytotoxicity experiments were performed to elucidate the possible antitumor activity of the tested substances. For this purpose, four cell lines were selected, namely human colon cancer (HCT-116), human adenocarcinoma (HeLa), human breast cancer (MDA-MB-231), and healthy human lung fibroblast (MRC-5) lines. A significant selectivity towards colorectal carcinoma cells was observed. Molecular docking and molecular dynamics studies with carbonic anhydrase, a prognostic factor in several cancers, complemented the experimental results. The calculated MD binding energies coincided well with the experimental activity, and indicated 4-hydroxycoumarin-dopamine and 4-hydroxycoumarin-3-methoxytyramine as the most active compounds. The ecotoxicology assessment proved that the obtained compounds have a low impact on the daphnia, fish, and green algae population. 相似文献