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New antimalarial drugs 总被引:6,自引:0,他引:6
Wiesner J Ortmann R Jomaa H Schlitzer M 《Angewandte Chemie (International ed. in English)》2003,42(43):5274-5293
Approximately 40% of the world population live in areas with the risk of malaria. Each year, 300-500 million people suffer from acute malaria, and 0.5-2.5 million die from the disease. Although malaria has been widely eradicated in many parts of the world, the global number of cases continues to rise. The most important reason for this alarming situation is the rapid spread of malaria parasites that are resistant to antimalarial drugs, especially chloroquine, which is by far the most frequently used. The development of new antimalarial drugs has been neglected since the 1970s owing to the end colonialism, changes in the areas of military engagement, and the restricted market potential. Only in recent years, in part supported by public funding programs, has interest in the development of antimalarial drugs been renewed. New data available from the recently sequenced genome of the malaria parasite Plasmodium falciparum and the application of methods of modern drug design promise to bring significant development in the fight against this disease. 相似文献
3.
Gabriele Sciacca Petra Martini Sara Cisternino Liliana Mou Jonathan Amico Juan Esposito Giancarlo Gorgoni Emiliano Cazzola 《Molecules (Basel, Switzerland)》2021,26(20)
Cyclotron-based radionuclides production by using solid targets has become important in the last years due to the growing demand of radiometals, e.g., 68Ga, 89Zr, 43/47Sc, and 52/54Mn. This shifted the focus on solid target management, where the first fundamental step of the radiochemical processing is the target dissolution. Currently, this step is generally performed with commercial or home-made modules separated from the following purification/radiolabelling modules. The aim of this work is the realization of a flexible solid target dissolution system to be easily installed on commercial cassette-based synthesis modules. This would offer a complete target processing and radiopharmaceutical synthesis performable in a single module continuously. The presented solid target dissolution system concept relies on an open-bottomed vial positioned upon a target coin. In particular, the idea is to use the movement mechanism of a syringe pump to position the vial up and down on the target, and to exploit the heater/cooler reactor of the module as a target holder. All the steps can be remotely controlled and are incorporated in the cassette manifold together with the purification and radiolabelling steps. The performance of the device was tested by processing three different irradiated targets under different dissolution conditions. 相似文献
4.
Yulin Ren Sijin Wu Joanna E. Burdette Xiaolin Cheng A. Douglas Kinghorn 《Molecules (Basel, Switzerland)》2021,26(12)
Digoxin is a cardiac glycoside long used to treat congestive heart failure and found recently to show antitumor potential. The hydroxy groups connected at the C-12, C-14, and C-3′a positions; the C-17 unsaturated lactone unit; the conformation of the steroid core; and the C-3 saccharide moiety have been demonstrated as being important for digoxin’s cytotoxicity and interactions with Na+/K+-ATPase. The docking profiles for digoxin and several derivatives and Na+/K+-ATPase were investigated; an additional small Asn130 side pocket was revealed, which could be useful in the design of novel digoxin-like antitumor agents. In addition, the docking scores for digoxin and its derivatives were found to correlate with their cytotoxicity, indicating a potential use of these values in the prediction of the cancer cell cytotoxicity of other cardiac glycosides. Moreover, in these docking studies, digoxin was found to bind to FIH-1 and NF-κB but not HDAC, IAP, and PI3K, suggesting that this cardiac glycoside directly targets FIH-1, Na+/K+-ATPase, and NF-κB to mediate its antitumor potential. Differentially, digoxigenin, the aglycon of digoxin, binds to HDAC and PI3K, but not FIH-1, IAP, Na+/K+-ATPase, and NF-κB, indicating that this compound may target tumor autophagy and metabolism to mediate its antitumor propensity. 相似文献
5.
为了研究靶材料对快电子能量分布的影响,采用电子谱仪测量了飞秒激光与Cu和CH靶相互作用中在靶前和靶后产生的快电子能谱。结果显示,在靶前Cu和CH靶的快电子能谱相似,反应了快电子发射对靶材料的依赖性较弱;在靶后Cu和CH靶的快电子能谱具有明显的差异,说明电子的输运过程与靶材料密切相关。冷电子环流以及自生磁场是导致Cu靶快电子能谱"软化"的原因,而对于CH靶麦克斯韦分布的快电子能谱主要由碰撞机制决定。 相似文献
6.
Xiaoding Lou 《中国化学快报》2019,30(9):1557-1564
The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the “false positives” results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials (1DMs) as well as two-dimensional materials (2DMs). 相似文献
7.
Using chemical separations and radiometric measurements medium-half-life irradiation products of molybdenum with 12.5 MeV deuterons were determined (90Nb, 92Nb, 95mNb, 95Nb, 96Nb, 99Mo, 95mTc, 96Tc, 99mTc) as well as thick target yields for some of them: 92Nb (0.22 μCi/μAh), 95Nb(0.05 μCi/μAh), 99Mo (64 μCi/μAh), 95mTc(0.76 μCi/μAh), 96Tc((62.5 μCi/μAh). Moreover isolation possibiities of radioactive preparations from removed worn-cut molybdenum parts of the U-120 cycletron are discussed. 相似文献
8.
高频地波雷达下的多目标跟踪数据处理 总被引:1,自引:0,他引:1
根据高频地波雷达监测海上低速移动目标的要求及该类雷达的特点,提出了一种与高频地波雷达目标跟踪相适应的多目标跟踪数据处理方案。在该方案中对BTC(bayes tracking confirm)方法与BTT(bayes tracking termination)方法进行了改进,解决了上述两种方法在高频地波雷达实际应用中存在的问题。提出了贝叶斯准则与次数判定相结合的跟踪起始和终结方法。模拟结果表明,该方案能够稳定、有效地实现高频地波雷达密集回波下的多目标跟踪。 相似文献
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10.
Direct Monitoring of Thickness and Refractive Index of Optical Thin Film Deposited on Fiber End-face
We propose a system for depositing thin films on waveguides which enables low-temperature deposition and precise control of the refractive index and film thickness. It is composed of a conventional ion-beam sputtering (IBS) system and a new system for directly monitoring film characteristics during deposition. We controlled refractive indices over a wide range from 1.52 to 1.97 by moving the sputtering targets (SiO2 and Si3N4) in the IBS system. The refractive index or film thickness was in-situ monitored by observing the optical power reflected from the end-face of a monitoring fiber set in the deposition chamber. Antireflection coating films were successfully deposited on a fiber end-face and a laser diode chip facet with low reflectivity from 0.05 to 0.07%. This deposition system is attractive for constructing highly functional optical devices for future photonic networks. 相似文献