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991.
T Furuta K Ohashi T Kamata M Takashima K Kosuge T Kawasaki H Hanai T Kubota T Ishizaki E Kaneko 《Canadian Metallurgical Quarterly》1998,129(12):1027-1030
We report a 65-year-old woman with thyrotropin (TSH) secreting pituitary adenoma, who was diagnosed based on the lack of inhibition of serum TSH despite an increased serum free thyroxine (T4), a low response of serum TSH to thyrotropin releasing hormone, and a pituitary tumor as revealed by magnetic resonance imaging. The pituitary adenoma was, however, inoperable due to chronic respiratory failure. The treatment with octreotide in a dose of 100 microg b.i.d. resulted in inhibition of serum TSH and free T4 to euthyroid levels and considerable shrinkage of the pituitary tumor. These effects were continued over 8 months after the start of octreotide therapy without any adverse effects. These findings add further evidence that octreotide is useful for treating inoperable TSH secreting pituitary adenoma. 相似文献
992.
Poly[9‐(2‐methacryloyloxyethyl)adenine] and poly[1‐(2‐methacryloyloxyethyl)thymine] with one pendant cholesteryl moiety at the polymer end (PMEA‐Chol, PMET‐Chol) and with two pendant cholesteryl moieties at both polymer ends as terminal groups (PMEA‐2Chol, PMET‐2Chol) were prepared by radical polymerization of 9‐(2‐methacryloyl‐oxyethyl)adenine (MEA) and 1‐(2‐methacryloyloxyethyl)thymine (MET) initiated with 4,4′‐azobis[(3‐cholesteryl)‐ 4‐cyanopentanoate] in the presence of 2‐mercaptoethanol or thiocholesterol as chain transfer reagents, respectively. The copolymers [PNiPAAm‐co‐PMEA‐nChol (n = 1,2)] composed of N‐isopropylacrylamide (NiPAAm) and MEA were also prepared in a similar manner. The self‐organization of these polymers and copolymers was confirmed by a fluorescence measurement, and then their critical concentrations of micelle formation (CMC) were determined. The mixture of PMEA‐2Chol and cholesterol as a lipophilic drug model formed a lamella type of complex with an interplaner spacing of d = 35.3 Å. The hypochromism based on the formation of a 1 : 1 interaction of adenine and thymine moieties was found to appear in the mixed aqueous solution of PMEA‐Chol and PMET‐Chol. Complementary interactions were also confirmed in the system of PMET‐2Chol and adenosine as well as PMEA‐2Chol and uridine. Cis‐dichlorodiammine platinum(II) (CDDP) was bound to PNiPAAm‐co‐PMEA‐Chol through the adenine moiety by ligand substitution atoms of CDDP. The amount of CDDP loaded on the copolymer was found to be 0.143 g g?1. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3064–3075, 2007 相似文献
993.
Takeshi Semba Kazuo Kitagawa Umaru S. Ishiaku Masaya Kotaki Hiroyuki Hamada 《应用聚合物科学杂志》2007,103(2):1066-1074
Side feeding technique was applied to poly (lactic acid) (PLA)/polycaprolactone (PCL) blends containing peroxide. Feeding procedures attempted were blanket and split feeding. In the former procedure, all the materials were fed into the main hopper at once. On the other hand, the feeding of materials was split by using main hopper and side feeder in the later procedure. The results indicated that static tensile properties were not dependent on feeding procedure, but the impact strength was superior in the case of the split feeding samples. It is noteworthy that the impact strength of the split feeding sample was considerably affected as it was four times better. Coarse dispersions such as continuous filament and layer dispersions were formed in the blend specimens without peroxide. On the other hand, fine dispersions were formed in the blend specimens containing peroxide which served as compatibilizer in this blend system. Peroxide addition through the side feeder brought about fine dispersions, promoted adhesion at the interface, and increased viscous nature of the PCL phase. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1066–1074, 2007 相似文献
994.
Michiaki Mori Yoneyoshi Kitagawa Ryosuke Kodama Hideaki Habara Manabu Iwata Saiji Tsuji Kenji Suzuki Kiyonobu Sawai Kazuo Tanaka Yoshiaki Kato Kunioki Mima 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1998,410(3):1290-372
The 30 TW GEKKO MII short pulse laser (25 J in 0.71 ps at 1 μm) is completed and is used for fast ignitor and particle accelerator research. The photon pressure of the laser at 1017-1018 W/cm2 pushed the critical and quarter critical density plasmas forward, resulting in the strong red shifts of the second (2ω0) and three-halves (3ω0/2) harmonic emissions backscattered from CH or CD planes. A few hundred keV proton and deuteron emissions are also observed from CD planes. 相似文献
995.
Dr. Kazuo Harada Shoko Aoyama Dr. Akimasa Matsugami Dr. Penmetcha K. R. Kumar Dr. Masato Katahira Dr. Nobuo Kato Dr. Junko Ohkanda 《Chembiochem : a European journal of chemical biology》2014,15(6):794-798
The stereochemical theory claims that primitive coded translation initially occurred in the RNA world by RNA‐directed amino acid coupling. In this study, we show that the HIV Tat aptamer RNA is capable of recognizing two consecutive arginine residues within the Tat peptide, thus demonstrating how RNA might be able to position two amino acids for sequence‐specific coupling. We also show that this RNA can act as a template to accelerate the coupling of a single arginine residue to the N‐terminal arginine residue of a peptide primer. The results might have implications for our understanding of the origin of translation. 相似文献
996.
Cover Picture: RNA‐Directed Amino Acid Coupling as a Model Reaction for Primitive Coded Translation (ChemBioChem 6/2014)
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997.
Thermoplastic composites of polyamide‐12 reinforced by cellulose nanofibers with cationic surface modification
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Takeshi Semba Akihiro Ito Kazuo Kitagawa Takeshi Nakatani Hiroyuki Yano Akihiro Sato 《应用聚合物科学杂志》2014,131(20)
Cellulose nanofibers (CNFs) have many useful properties, including high strength and low thermal expansion, and are also environmentally friendly, readily renewable, safe, and biodegradable. The focus of this study was the development of lightweight thermoplastic polymer composites with good mechanical properties based on the incorporation of CNFs that have undergone surface pretreatment with a cationic reagent. The polyamide (PA12) was mixed with surface‐treated CNFs using a twin screw extruder and the resulting pellets were injection molded. The Izod impact strength without notch of CNF‐based composites exceeded that of composites incorporating organophilic montmorillonite (OMMT), a representative nanocomposite material. When the Izod impact test without notch, the impact hammer was stopped by the specimen with incorporation of surface treated CNF. Furthermore, the bending modulus and strength were equal to or greater than that of OMMT composites. The heat distortion temperature was improved as 33°C from neat PA12, and moreover improved as 29°C from OMMT composites. Cationic pretreatment of the CNF surfaces was found to increase the dispersion of the fibers and also to greatly improve the mechanical and thermal properties of the composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40920. 相似文献
998.
Formation of Acrolein in the Autoxidation of Triacylglycerols with Different Fatty Acid Compositions
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Ako Shibata Mariko Uemura Masashi Hosokawa Kazuo Miyashita 《Journal of the American Oil Chemists' Society》2015,92(11-12):1661-1670
Fish, echium, linseed, and soybean oil triacyglycerols (TAGs) were oxidized at 50 or 60 °C to determine the effect of the polyunsaturated fatty acid composition on the volatile product formation. The analysis of the oxygen consumption and total volatile formation demonstrated that the soybean oil TAG had the highest oxidative stability followed by linseed, echium, and fish oil TAGs. Our results were in agreement with the expected average number of bis‐allylic positions of each TAG. Higher quantities of acrolein (2‐propenal) and propanal were detected using the static headspace gas chromatography method at the early stages of oxidation of echium and fish oil TAGs; however, a considerable amount of propanal and only a small amount of acrolein were found in the oxidized linseed oil TAG. The peak area ratios of acrolein to propanal were 0.115, 0.569, and 2.554 after the 8‐h oxidation of linseed, echium, and fish oil TAG, respectively, suggesting the preferential formation of acrolein, especially during the fish oil TAG oxidation. The acrolein quickly increased during the first stage of oxidation, but thereafter it either did not change or slightly decreased during the fish oil oxidation. Because fish oil induces flavor deterioration from the very early stage of the oxidation, the acrolein formation observed in the present study may be important for fish oil deterioration. 相似文献
999.
Organic Electronics: Towards Colorless Transparent Organic Transistors: Potential of Benzothieno[3,2‐b]benzothiophene‐Based Wide‐Gap Semiconductors (Adv. Mater. 19/2014)
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Hanul Moon Hyunsu Cho Mincheol Kim Kazuo Takimiya Seunghyup Yoo 《Advanced materials (Deerfield Beach, Fla.)》2014,26(19):3163-3163
1000.
Yoko Takada Toru Tsuji Naoki Okamoto Takeyasu Saito Kazuo Kondo Takeshi Yoshimura Norifumi Fujimura Koji Higuchi Akira Kitajima Akihiro Oshima 《Journal of Materials Science: Materials in Electronics》2014,25(5):2155-2161
Conductive aluminum-doped zinc oxide (AZO) was deposited by pulsed laser deposition as top electrodes for chemical solution deposition derived lanthanum modified lead zirconate titanate (PLZT) capacitors. Compared with PLZT capacitors with Pt top electrodes (Pt/PLZT/Pt), PLZT capacitors with AZO as top electrodes (AZO/PLZT/Pt) showed improved fatigue endurance after cycles of 200 kV/cm (10 V) were applied with a 100 μs pulse width at 1 ms intervals. By using a combination of AZO as the top electrode and as a thin buffer layer (10 nm) under PLZT thin films (AZO/PLZT/AZO/Pt), fatigue behavior was also improved compared with the case without an AZO buffer layer. The addition of either an Al2O3 or HfO2 encapsulation layer increased the remnant polarization ratio of PLZT capacitors (after annealing at 200 °C, 1 Torr, 3 % hydrogen atmosphere) to 0.80 and 0.57, respectively, comparing with 0.52 without an encapsulation layer. 相似文献