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101.
Parasitic diseases are still a huge problem for mankind. They are becoming the main cause of chronic diseases in the world. Migration of the population, pollution of the natural environment, and climate changes cause the rapid spread of diseases. Additionally, a growing resistance of parasites to drugs is observed. Many research groups are looking for effective antiparasitic drugs with low side effects. In this work, we present the current trends in the search for antiparasitic drugs. We report known drugs used in other disease entities with proven antiparasitic activity and research on new chemical structures that may be potential drugs in parasitic diseases. The described investigations of antiparasitic compounds can be helpful for further drug development.  相似文献   
102.
The cerebral cortex performs its computations with many six-layered fundamental units, collectively spreading along the cortical sheet. What is the local network structure and the operating dynamics of such a fundamental unit? Previous investigations of primary sensory areas revealed a classic “canonical” circuit model, leading to an expectation of similar circuit organization and dynamics throughout the cortex. This review clarifies the different circuit dynamics at play in the higher association cortex of primates that implements computation for high-level cognition such as memory and attention. Instead of feedforward processing of response selectivity through Layers 4 to 2/3 that the classic canonical circuit stipulates, memory recall in primates occurs in Layer 5/6 with local backward projection to Layer 2/3, after which the retrieved information is sent back from Layer 6 to lower-level cortical areas for further retrieval of nested associations of target attributes. In this review, a novel “dynamic multimode module (D3M)” in the primate association cortex is proposed, as a new “canonical” circuit model performing this operation.  相似文献   
103.
宋天佑  王莉  张丽荣  徐家宁 《化学教育》2022,43(14):100-104
回顾了吉林大学无机化学学科教材建设的历史,从恢复高考招生制度后我国的第一部无机化学教材的编写,到该书第2版、第3版的修订,到配套的无机化学实验教材及无机化学习题集、无机化学习题解答的编写,处处凝结着无机化学教师们智慧的结晶,形成了厚重的历史积淀。随着新世纪的到来,顺应新时代要求、新兴的编者队伍在教学实践中成长壮大,编写出全新的无机化学教材。经过几代教师的努力,无机化学教材不断发展和完善,形成了多层次、系统性、立体化、高质量的精品无机化学教材体系,可满足不同层次、不同专业、不同教学计划的需求,在全国高校无机化学教学活动中发挥了重要作用。  相似文献   
104.
周燕  郭建友 《中国物理 B》2008,17(2):380-384
In this paper a new ring-shaped harmonic oscillator for spin 1/2 particles is studied, and the corresponding eigenfunctions and eigenenergies are obtained by solving the Dirac equation with equal mixture of vector and scalar potentials. Several particular cases such as the ring-shaped non-spherical harmonic oscillator, the ring-shaped harmonic oscillator, non-spherical harmonic oscillator, and spherical harmonic oscillator are also discussed.  相似文献   
105.
A new method to protect the copyright of digital museum based on digital holography is proposed. The Fresnel hologram of watermark image is embedded in the object to be protected through discrete wavelet transform (DWT). After the watermark detection, the copyright information appears in the reconstructed hologram. With the higher redundancy feature in the hologram, the proposed technique can actually survive several kinds of image processing. Experimental results prove that the presented method has good robustness in image protection.  相似文献   
106.
Synchronization and coherent combining of two pulsed fiber lasers   总被引:1,自引:0,他引:1  
We demonstrate a scalable architecture for coherent combining of pulsed fiber lasers.A new method for generating synchronous pulsed fiber lasers by direct phase modulation is proposed and investigated.It is shown that phase modulated mutually coupled laser array can be a steady synchronous pulsed fiber laser source.The synchronous pulsed fiber lasers are coherently combined with an invariable phase difference of π in adjacent lasers.Neither active phase control nor polarization control is taken in our experiment.  相似文献   
107.
108.
Due to the directed way of testing chemical compounds' in drug research and development many projects fail because serious adverse effects and toxicity are discovered too late, and many existing prospective activities remain unstudied. Evaluation of the general biological potential of molecules is possible using a computer program PASS that predicts more than 780 pharmacological effects, mechanisms of action, mutagenicity, carcinogenicity, etc. on the basis of structural formulae of compounds, with average accuracy 85%. PASS applications to both databases of available samples included hundreds of thousands compounds, and small collections of compounds synthesized by separate medicinal chemists are described. It is shown that 880 compounds from Prestwick chemical library represent a very diverse pharmacological space. New activities can be found in existing compounds by prediction. Therefore, on this basis, the selection of compounds with required and without unwanted properties is possible. Even when PASS cannot predict very new activities, it may recognize some unwanted actions at the early stage of R&D, providing the medicinal chemist with the means to increase the efficiency of projects.  相似文献   
109.
An extended electromagnetic theory has earlier been developed, as being based on the hypothesis of a nonzero electric field divergence in vacuo and the requirement of Lorentz invariance. This basis is supported by the commonly accepted fact that the vacuum is not merely an empty space, but has a ground state of nonzero energy and can become electrically polarized. The vacuum is thereby considered as electrically polarizable in the sense of being capable of supporting charge motion in the form of, e.g., space-charge waves. One result of the dynamic states of the present theory is the prediction of a purely longitudinal electric space-charge wave (S-wave) having no induced magnetic field. The behaviour of this wave type is demonstrated for a number of geometrical configurations. Some preliminary proposals are finally made for generation and detection of S waves. These waves are expected to have features which differ from those of the conventional transverse electromagnetic waves. If the S wave would come out to be physically realizable, it may thus form the basis of a new principle for telecommunication without or with very small magnetic induction effects.  相似文献   
110.
Altarelli  Guido 《Pramana》2004,62(2):149-161
We present a concise review of the status of the standard model and of the search for new physics.  相似文献   
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