全文获取类型
收费全文 | 792篇 |
免费 | 74篇 |
国内免费 | 1篇 |
出版年
2023年 | 6篇 |
2022年 | 16篇 |
2021年 | 32篇 |
2020年 | 24篇 |
2019年 | 24篇 |
2018年 | 34篇 |
2017年 | 26篇 |
2016年 | 33篇 |
2015年 | 41篇 |
2014年 | 60篇 |
2013年 | 61篇 |
2012年 | 68篇 |
2011年 | 72篇 |
2010年 | 31篇 |
2009年 | 36篇 |
2008年 | 53篇 |
2007年 | 51篇 |
2006年 | 42篇 |
2005年 | 33篇 |
2004年 | 35篇 |
2003年 | 34篇 |
2002年 | 26篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1978年 | 2篇 |
1962年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有867条查询结果,搜索用时 15 毫秒
851.
Maxim E. Darvin Chunsik Choe Johannes Schleusener Sehyok Choe Jürgen Lademann 《Journal of biophotonics》2020,13(6)
The presence of penetrated oils in the stratum corneum (SC), oil‐induced occlusion of the SC and formation of occluding homogeneous film on the skin surface are discussed in relation to their influence on results of water profile calculations using conventional and newly proposed extended methods. It is shown that the conventional method does not determine the water profiles in treated skin correctly due to the superposition of Raman bands of SC's proteins and penetrated and remnant oils. 相似文献
852.
Vitaliy O. Kaminskyy Maxim D. Lootsik Rostyslav S. Stoika 《Central European Journal of Biology》2006,1(1):2-15
The purpose of this study was to examine the relationship between the DNA intercalating characteristics and the DNA damaging
capacity of four alkaloids extracted from Chelidonium majus L, as well as their toxicity towards murine NK/Ly lymphoma cells. Chelerythrine, sanguinarine and coptisine were found to be
intercalated into the DNA isolated from NK/Ly cells, meanwhile, chelidonine exhibited no affinity to DNA. Sanguinarine exhibited
the greatest toxicity toward NK/Ly cells, and the toxicity of the other three decreased in descending order: chelerythrine,
coptisine and chelidonine. Chelerythrine and sanguinarine caused DNA damage, illustrated by the formation of comets of the
third class. Coptisine was less toxic than chelerythrine and sanguinarine, and affected the formation the same class of comets
in higher concentration. The quantity of comets induced by chelidonine were negligible, a finding consistent with its inability
to intercalate into DNA structure. The ability of four main alkaloids of Chelidonium majus L., to intercalate into DNA isolated from murine NK/Ly lymphoma cells, correlated with their ability to induce breaks in cellular
DNA and with their toxic effect towards those cells. 相似文献
853.
M. Deminsky A. Eletskii A. Kniznik A. Odinokov V. Pentkovskii B. Potapkin 《The Journal of membrane biology》2013,246(11):821-831
A molecular dynamic approach was applied for simulation of dynamics of pore formation and growth in a phospholipid bilayer in the presence of an external electric field. Processing the simulation results permitted recovery of the kinetic coefficients used in the Einstein–Smoluchowski equation describing the dynamics of pore evolution. Two different models of the bilayer membrane were considered: membrane consisting of POPC and POPE lipids. The simulations permitted us to find nonempirical values of the pore energy parameters, which are compared with empirical values. It was found that the parameters are sensitive to membrane type. 相似文献
854.
Maxim Zhadobov Robin Augustine Ronan Sauleau Stanislav Alekseev Alessandra Di Paola Catherine Le Quément Yonis Soubere Mahamoud Yves Le Dréan 《Bioelectromagnetics》2012,33(4):346-355
The main purpose of this study is to provide experimental data on the complex permittivity of some biological solutions in the 2–67 GHz range at room and human body temperatures. The permittivity measurements are performed using an open‐ended coaxial probe. Permittivity spectra of several representative monomolecular solutions of proteins, amino acids, nucleic acids, and carbohydrates are analyzed and compared. Furthermore, measurements have also been performed for complex biomolecular solutions, including bovine serum albumin (BSA)–DNA–glucose mixture, culture medium, and yeast extract solution. The results demonstrate that for concentrations below 1%, the permittivity spectra of the solutions do not substantially differ from that of distilled water. Measurements carried out for 4% and 20% BSA solutions show that the presence of proteins results in a decrease in permittivity. For highly concentrated RNA solutions (3%), a slight increase in the imaginary part of the permittivity is observed below 10 GHz. Experimental data show that free water permittivity can be used for modeling of the culture medium above 10 GHz. However, at lower frequencies a substantial increase in the imaginary part of the permittivity due to ionic conductivity should be carefully taken into account. A similar increase has also been observed for the yeast extract solution in the lower frequency region of the considered spectrum. Above 10 GHz, the high concentration of proteins and other low‐permittivity components of the yeast extract solution results in a decrease in the complex permittivity compared to that of water. Obtained data are of utmost importance for millimeter‐wave dosimetry studies. Bioelectromagnetics 33:346–355, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
855.
856.
Maxim A. Ivanov Vladimir V. Sharutin Antonya P. Pakusina Willis Forsling 《Inorganica chimica acta》2007,360(9):2897-2904
O,O′-dipropyldithiophosphate and O,O′-di-iso-butyldithiophosphate (Dtph) tetraphenylantimony(V) complexes of the general formula [Sb(C6H5)4{S2P(OR)2}] (R = C3H7, i-C4H9) were prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. Distorted octahedral and trigonal bipyramidal molecular structures have been established for prepared complexes. These unexpected structural distinctions between chemically related compounds are defined by the principally different coordination modes of O,O′-dipropyldithiophosphate and O,O′-di-iso-butyldithiophosphate ligands in their molecular structures (i.e., S,S′-bidentate chelating and S-unidentately coordinated, respectively). To characterise quantitatively phosphorus sites in both species of dithiophosphate ligands, 31P chemical shift anisotropy parameters (δaniso and η) were calculated from spinning sideband manifolds in MAS NMR spectra. The 31P chemical shift tensors for the bidentate chelating and unidentately coordinated dithiophosphate ligands display a profoundly rhombic and nearly axially symmetric characters, respectively. 相似文献
857.
858.
859.
BioMetals - The tellurium oxyanion tellurate is toxic to living organisms even at low concentrations; however, its mechanism of toxicity is poorly understood. Here, we show that exposure of... 相似文献
860.
Maxim V Trushin 《Theoretical biology forum》2004,97(3):409-442
Communication is a natural ability of all living systems. It is very likely that various types of communication were evolved during evolution. While the communication by means of chemicals, direct contact or via organs of sense is under intensive study for a long time, alternative ways of interaction are still considered debatable, This review covers the topic of physically mediated communication in various biological systems. 相似文献