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991.
An efficient method for the synthesis of peptides bearing an amide at the C-terminal is described. This method involves the attachment of a C-terminal protecting group bearing long aliphatic chains, followed by the repetition of simple reaction and precipitation steps with the combined advantages of liquid-phase peptide synthesis (LPPS) and solid-phase peptide synthesis (SPPS). Using this method, a hydrophobic peptide was successfully synthesized in good yield and high purity, which cannot be obtained satisfactorily by SPPS. 相似文献
992.
Kanki A Tamada T Higaki A Noda Y Tanimoto D Sato T Higashi H Ito K 《Magnetic resonance imaging》2012,30(3):356-360
The aim was to clarify whether enhancement effects of the liver parenchyma in the hepatobiliary phase (HP) of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR imaging were correlated with the morphological grading of the severity in cirrhosis. A total of 62 patients with chronic hepatitis or cirrhosis underwent Gd-EOB-DTPA-enhanced MR imaging. Relative enhancement (RE) of liver parenchyma was calculated from signal intensity (SI) measurements obtained at precontrast images (SIpre) and 20-min postcontrast HP images (SIpost) as: (SIpost-SIpre)/SIpre. Morphological MR grades of severity in cirrhosis were divided into four groups. Then, RE of liver parenchyma and morphologic MR grading were correlated. Regarding the morphologic severity of cirrhosis, the numbers of patients with MR grade 1, 2, 3 and 4 were 14 (23%), 7 (11%), 28 (45%) and 13 (21%), respectively. The mean REs of liver parenchyma in each group of MR morphologic grade 1, 2, 3 and 4 were 0.71±0.21, 0.62±0.16, 0.70±0.22 and 0.77±0.18, respectively. There was no significant correlation between the MR grading of morphologic severity and the RE of liver parenchyma at 20-min HP. Hepatic parenchymal enhancement in the HP of Gd-EOB-DTPA-enhanced MR imaging did not necessarily decrease according to the severity of morphologic changes in cirrhosis. This fact may suggest that the hepatic uptake of Gd-EOB-DTPA depends on the preserved hepatocytes function rather than the severity of morphologic changes in cirrhosis. 相似文献
993.
Kenichiro Takakura Suguru Funasaki Isao Tsunoda Hidenori Ohyama Daisuke Takeuchi Toshiyuki Nakashima Mutsuo Shibuya Katsuya Murakami Eddy Simoen Cor Claeys 《Physica B: Condensed Matter》2012,407(15):2900-2902
A transparent electrode of Si doped β-Ga2O3 films for solar cells, flat panel displays and other devices, which consists of chemically abundant and ecological friendly elements of gallium and oxygen, was grown on silicon substrates by RF magnetron sputtering using sintered Ga2O3 and Si target. The Si composition in the β-Ga2O3 film is determined by electron dispersive X-ray spectroscopy. The X-ray photoelectron spectroscopy peak ratio of oxygen over gallium decreases with increasing Si content. It is concluded that Si substitutes for the Ga sites in the β-Ga2O3 film. 相似文献
994.
Yaku H Fujimoto T Murashima T Miyoshi D Sugimoto N 《Chemical communications (Cambridge, England)》2012,48(50):6203-6216
A G-quadruplex is a four-stranded DNA structure featuring stacked guanine tetrads, G-quartets. Formation of a G-quadruplex in telomere DNA can inhibit telomerase activity; therefore, development of G-quadruplex-ligands, which induce and/or stabilize G-quadruplexes, has become an area of great interest. Phthalocyanine derivatives have substantial potential as high-affinity G-quadruplex-ligands because these planar chromophores are similar in size and shape to the G-quartets. Here, we focus on the latest findings on phthalocyanine derivatives as G-quadruplex-ligands, and discuss the mechanisms by which phthalocyanines bind to G-quadruplexes with high affinity and selectivity. We also discuss potential biomedical and organic electronic applications of phthalocyanines that are dependent on their photophysical properties. 相似文献
995.
We describe the construction of an aptazyme-based molecular device that converts, through a cascade of reactions, a small-molecule input into output RNA strands. This device is applicable as an interface between a small molecule and a molecular system that accepts only nucleic acid input. 相似文献
996.
Tanaka D Inose T Tanaka H Lee S Ishikawa N Ogawa T 《Chemical communications (Cambridge, England)》2012,48(63):7796-7798
A tetraphenylporphyrin based Tb(III) double-decker complex has been synthesized and the crystal structure of both protonated and deprotonated forms has been determined. The ac magnetic susceptibility measurements revealed that the SMM properties of the double-decker complex can be reversibly switched by only a single proton. 相似文献
997.
Color digital holography utilizing the Doppler effect is proposed. The time variation of holograms produced by superposing images at three wavelengths is recorded using a high-speed monochromatic imaging sensor. The complex amplitude at each wavelength can be extracted from frequency information contained in the Fourier transforms of the recorded holograms. An image of the object is reconstructed by the angular spectrum method. Reconstructed monochromatic images at the three wavelengths are combined to produce a color image for display. 相似文献
998.
Daisuke Sato Koya Yamashiro Hideaki Onishi Yoshimitsu Shimoyama Takuya Yoshida Atsuo Maruyama 《BMC neuroscience》2012,13(1):13
Background
Water immersion therapy is used to treat a variety of cardiovascular, respiratory, and orthopedic conditions. It can also benefit some neurological patients, although little is known about the effects of water immersion on neural activity, including somatosensory processing. To this end, we examined the effect of water immersion on short-latency somatosensory evoked potentials (SEPs) elicited by median nerve stimuli. Short-latency SEP recordings were obtained for ten healthy male volunteers at rest in or out of water at 30°C. Recordings were obtained from nine scalp electrodes according to the 10-20 system. The right median nerve at the wrist was electrically stimulated with the stimulus duration of 0.2 ms at 3 Hz. The intensity of the stimulus was fixed at approximately three times the sensory threshold. 相似文献999.
Pradip Ghosh Shunsaku Satou Hiroaki Nakamori Takuto Noda Ishii Daisuke Masaki Tanemura 《固体物理学:研究快报》2012,6(11):430-432
Highly transparent (transparency 96.5%), flexible and antireflective superhydrophobic (water contact angle >150°) surfaces have been fabricated at room temperature by the ion irradiation method. This one‐step fabrication route was fairly easy to carry out without any heat or chemical treatment and can be completed within few seconds. This novel chemical free fabricating strategy could be extended to numerous polymeric substrates to achieve transparent and flexible superhydrophobic structures for their potential applications in diverse fields. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
Satoshi Tohoda Daisuke Fujishima Ayumu Yano Akiyoshi Ogane Kenta Matsuyama Yuya Nakamura Nozomu Tokuoka Hiroshi Kanno Toshihiro Kinoshita Hitoshi Sakata Mikio Taguchi Eiji Maruyama 《Journal of Non》2012,358(17):2219-2222
To reduce the power generation cost of heterojunction with intrinsic thin layer (HIT) solar cells, it is necessary to use a thinner crystalline silicon wafer, as well as to improve the conversion efficiency. We have experimentally confirmed that VOC of the HIT solar cell increases with decreasing the wafer thickness, and can reach a very high VOC of 747 mV with a 58-μm-thick wafer owing to a sufficiently low surface recombination velocity. We also indicate the future directions for improving the efficiency. The uniformization of the texture size of the silicon surface and reduction of the carrier density in TCO film while maintaining an equal or lower conductivity are effective for improving the optical confinement. 相似文献