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991.
L. Lis 《Il Nuovo Cimento D》1990,12(7):935-940
Summary In this report investigations are presented of laser generations at 3391 nm and 3391 and 7699 nm, or rather of changes induced
by them in populations of the 5s′ [1/2]
1
0
, 4p′[3/2]2 and 3d′[5/2]
3
0
levels, depending upon the angle of the tilted mirror of the He−Ne laser system. This writer has discovered that the above
laser generations develop at a strongly tilted mirror, when the beam reflected from one mirror, in order to reach the other,
has to be reflected many times on the inside walls of the discharge tube.
The work was supported by CPBR 8.14. 相似文献
992.
Kazuo Furihata Sakurako Shimotakahara Yoichi Shibusawa Mitsuru Tashiro 《Magnetic resonance in chemistry : MRC》2009,47(11):971-976
An efficient pulse sequence for observing the ligand signals resonating close to the water signal has been developed by incorporating the WET technique into the saturation transfer difference pulse sequence. Although several pulse sequences have been developed for observing a ligand binding with a protein receptor, the ligand signals resonating close to the water were undetectable owing to the interference of the huge water signal in the samples containing 95% 1H2O. On the point of sample preparation, it is preferable to avoid the solvent exchange in the protein samples. In the proposed pulse sequence, a WET sequence is incorporated for the selective suppression of the water resonance. The efficient water suppression and the clear observation of the bound ligand signals close to the water have been demonstrated using the lysozyme‐glucose complex. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
993.
994.
Mariana Cristea Daniela Gheorghiu Ionita Maria Bruma B. C. Simionescu 《Journal of Thermal Analysis and Calorimetry》2008,93(1):63-68
Two aromatic polyimides and the corresponding poly(amic acid)s, with oxadiazole and para/meta phenoxyphenylene rings in the backbone, were synthesized and the structure — thermal properties correlation was followed
by dynamic mechanical analysis. Concerning the poly(amic acid)s, the glass transition domain was emphasized only for the compound
with meta-oriented rings because the process of imidization takes place with increasing temperature. A multiplex experiment was performed
to calculate the activation energy of the transition localized under 200°C. Consecutive heating-cooling-heating cycles were
accomplished. All phenomena are discussed by cross-examination of the storage modulus (E′), loss modulus (E″) and loss factor tanδ variation with temperature. 相似文献
995.
996.
997.
Laura Escuder‐Gilabert María Amparo Martínez‐Gómez Rosa María Villanueva‐Camañas Salvador Sagrado María José Medina‐Hernández 《Biomedical chromatography : BMC》2009,23(3):225-238
Stereoselectivity in protein binding can have a significant effect on the pharmacokinetic and pharmacodynamic properties of chiral drugs. The investigation of enantioselectivity of drugs in their binding with human plasma proteins and the identification of the molecular mechanisms involved in the stereodiscrimination by the proteins represent a great challenge for clinical pharmacology. In this review, the separation techniques used for enantioselective protein binding experiments are described and compared. An overview of studies on enantiomer–protein interactions, enantiomer–enantiomer interactions as well as chiral drug–drug interactions, including allosteric effects, is presented. The contribution of individual plasma proteins to the overall enantioselective binding and the animal species variability in drug–plasma protein binding stereoselectivity are reviewed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
998.
Sarah R. Dennison Leslie H.G. Morton Andrea J. Shorrocks Frederick Harris David A. Phoenix 《Colloids and surfaces. B, Biointerfaces》2009,68(2):225-230
Aurein 2.5 (GLFDIVKKVVGAFGSL-NH2) is an uncharacterised antimicrobial peptide. At an air/water interface, it exhibited strong surface activity (maximal surface pressure 25 mN m−1) and molecular areas consistent with the adoption of α-helical structure orientated either perpendicular (1.72 nm2 molecule−1) or parallel (3.6 nm2 molecule−1) to the interface. Aurein 2.5 was strongly antibacterial, exhibiting a minimum inhibitory concentration (MIC) of 30 μM against Bacillus subtilis and Escherichia coli. The peptide induced maximal surface pressure changes of 9 mN m−1 and 5 mN m−1, respectively, in monolayers mimicking membranes of these organisms whilst compression isotherm analysis of these monolayers showed ΔGMix > 0, indicating destabilisation by Aurein 2.5. These combined data suggested that toxicity of the peptide to these organisms may involve membrane invasion via the use of oblique orientated α-helical structure. The peptide induced strong, comparable maximal surface changes in monolayers of DOPG (7.5 mN m−1) and DOPE monolayers (6 mN m−1) suggesting that the membrane interactions of Aurein 2.5 were driven by amphiphilicity rather than electrostatic interaction. Based on these data, it was suggested that the differing ability of Aurein 2.5 to insert into membranes of B. subtilis and E. coli was probably related to membrane-based factors such as differences in lipid packing characteristics. The peptide was active against both sessile E. coli and Staphylococcus aureus with an MIC of 125 μM. The broad-spectrum antibacterial activity and non-specific modes of membrane action used by Aurein 2.5 suggested use as an anti-biofilm agent such as in the decontamination of medical devices. 相似文献
999.
1000.