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71.
G A O'Brien J M Corbett M J Dunn D V Cumming A J May M H Yacoub 《Electrophoresis》1992,13(9-10):726-728
Sheep latissimus dorsi muscle was electrically trained, thereby inducing fast-to-slow fibre-type transformation. Using a combination of one- and two-dimensional gel electrophoresis techniques with computer analysis, we have analysed altered expression of contractile protein isoforms at protein and mRNA level over a time course of electrical training extending to 5 months. Myosin heavy chain and regulatory myosin light chain analysis showed predominant expression of their slow isoforms (86% and 92%, respectively) after 3 months of training. At the same time point, however, tropomyosin analysis revealed that the slow isoform of the alpha-subunit accounted for 64% of the total alpha expression. Troponin T isoform switching proceeded more slowly over the same time course than tropomyosin and the thick filament proteins studied. Troponin T analysis revealed 5 fast and 2 slow isoforms in the sheep, of which the second slow isoform only became clearly visible after 5 months' training. At this time point the two slow isoforms were more predominant than their fast counterparts. This suggests that a wide heterogeneity of fast and slow isoform combinations are possible in the thin filament of skeletal muscle. 相似文献
72.
Paul Cumming Milan Scheidegger Dario Dornbierer Mikael Palner Boris B. Quednow Chantal Martin-Soelch 《Molecules (Basel, Switzerland)》2021,26(9)
Hallucinogens are a loosely defined group of compounds including LSD, N,N-dimethyltryptamines, mescaline, psilocybin/psilocin, and 2,5-dimethoxy-4-methamphetamine (DOM), which can evoke intense visual and emotional experiences. We are witnessing a renaissance of research interest in hallucinogens, driven by increasing awareness of their psychotherapeutic potential. As such, we now present a narrative review of the literature on hallucinogen binding in vitro and ex vivo, and the various molecular imaging studies with positron emission tomography (PET) or single photon emission computer tomography (SPECT). In general, molecular imaging can depict the uptake and binding distribution of labelled hallucinogenic compounds or their congeners in the brain, as was shown in an early PET study with N1-([11C]-methyl)-2-bromo-LSD ([11C]-MBL); displacement with the non-radioactive competitor ketanserin confirmed that the majority of [11C]-MBL specific binding was to serotonin 5-HT2A receptors. However, interactions at serotonin 5HT1A and other classes of receptors and pleotropic effects on second messenger pathways may contribute to the particular experiential phenomenologies of LSD and other hallucinogenic compounds. Other salient aspects of hallucinogen action include permeability to the blood–brain barrier, the rates of metabolism and elimination, and the formation of active metabolites. Despite the maturation of radiochemistry and molecular imaging in recent years, there has been only a handful of PET or SPECT studies of radiolabeled hallucinogens, most recently using the 5-HT2A/2C agonist N-(2[11CH3O]-methoxybenzyl)-2,5-dimethoxy- 4-bromophenethylamine ([11C]Cimbi-36). In addition to PET studies of target engagement at neuroreceptors and transporters, there is a small number of studies on the effects of hallucinogenic compounds on cerebral perfusion ([15O]-water) or metabolism ([18F]-fluorodeoxyglucose/FDG). There remains considerable scope for basic imaging research on the sites of interaction of hallucinogens and their cerebrometabolic effects; we expect that hybrid imaging with PET in conjunction with functional magnetic resonance imaging (fMRI) should provide especially useful for the next phase of this research. 相似文献
73.
A viscose-rayon-based activated carbon cloth (ACC) was electrochemically oxidized to enhance its cation sorption capacity for comparison with as-received ACC. The ACCs were characterized by sodium capacity measurement, pH titration, zeta potential measurement, elemental analysis, Brunauer-Emmet-Teller surface area, and pore size distribution. Batch sorption experiments showed that electrochemically oxidized ACC (EO) is more effective for the removal of lead and copper ions compared to unoxidized ACC (UO) for both competitive and noncompetitive sorption. For electrochemically oxidized fibers the copper and lead sorption capacities of ACC increased 17 and 4 times, respectively, for noncompetitive sorption and 8.8 and 8.6 times, respectively, for competitive sorption. However, reduction in the sorption capacities for both metals was observed for the competitive sorption. The sorption of lead and copper onto EO was by ion exchange, while that onto UO was likely to be due to surface complex formation. The affinity order of the two metal ions sorbed by UO and EO is Pb(2+)>Cu(2+). The effect of pH on sorption isotherms indicated that metal uptake increased with an increase in solution pH. 相似文献
74.
以功能性的钌有机螯合物Ru(phen) 2 + 3 作为亚相离子 ,花生酸在亚相表面上形成稳定的单分子膜 .π A等温线和动态弹性测量表明 ,此膜因花生酸与钌螯离子发生了静电相互作用而有更大的可压缩性 ,并在固态区发生了分子聚集 .用垂直法成功地制备了嵌有Ru(phen) 2 + 3 离子的超薄有序Y 型LB膜 .光谱实验表明 ,所得LB膜是稳定、均匀的层状三明治结构 ,在层面内Ru(phen) 2 + 3 与花生酸结合成相对稳定的分子基团并形成了J 聚体 相似文献
75.
Ohne Zusammenfassung 相似文献
76.
77.
W.M. Cumming 《Fresenius' Journal of Analytical Chemistry》1925,66(4-5):173-174
Ohne Zusammenfassung 相似文献
78.
Earl M. Anger K. Schröder R. E. Lowe M. A. Mammen L. R. Taylor R. H. Griffith G. C. Holliday H. E. Roscoe F. Scudder H. Bunte E. Terres A. Mittasch W. M. Cumming W. Good und P. Budnikoff 《Fresenius' Journal of Analytical Chemistry》1929,78(7-8):305-315
Ohne Zusammenfassung 相似文献
79.
J. H. Stansbie E. Gilchrist A. Ch. Cumming J. R. Withrow Arthur J. White R. Belasio M. Marchionneschi Ch. Lind W. D. Treadwell A. Sieverts W. Wippelmann H. Graefe Geo Kemerer E. B. Spear S. S. Strahan C. B. Spear E. E. Tainton A. Mazzuchelli B. L. Murray E. P. Schoch F. M. Crawford und John H. Reedy 《Fresenius' Journal of Analytical Chemistry》1917,56(5):246-253
Ohne Zusammenfassung 相似文献
80.
David R.S. Cumming 《Optics Communications》2006,259(1):373-377
Beam-steering techniques are required to fully exploit the benefits of present and future terahertz imaging systems. We propose and model a device that overcomes the difficulties that prevent analogues of existing electrical and optical micro-mechanical techniques being employed at terahertz frequencies. The device employs a variable phase-control medium comprised of interlocking artificial dielectric surfaces. We present an analytical array factor calculation that provides insight into the operation of the device and an improved discrete array factor model incorporating the complex transmission coefficients of the structure. The models are validated by comparison to results from a rigorous full-vector electromagnetic solver tool (finite-difference time-domain). We predict a practical device constructed from a silicon substrate could steer both TE and TM beams by up to 6.4°. 相似文献