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Hiroto Kinoshita Hitomi Nishioka Aya Ikeda Kyoko Ikoma Yoichi Sameshima Hidehisa Ohi Mizuki Tatsuno Junka Kouyama Chiaki Kawamoto Tomohiro Mitsui Yuko Tamura Yu Hashimoto Masashi Nishio Tsuyoshi Ogashiwa Yusuke Saigusa Shin Maeda Hideaki Kimura Reiko Kunisaki Kazuhiko Koike 《Journal of gastroenterology and hepatology》2019,34(11):1929-1939
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A 1:1 adduct of methyl sorbate (MS) and 1,3‐di‐tert‐butylimidazol‐2‐ylidene (NHCtBu) initiates anionic polymerization of a nonconjugated polar alkene, allyl methacrylate (AMA) in toluene at ?20 °C. After the monomer is consumed quantitatively using a bulky aluminum Lewis acid, methylaluminum bis(2,6‐di‐tert‐butyl‐4‐methylphenoxide) (MAD), as an additive, successive ring‐closure occurs without highly dilute conditions to give a cyclic poly(AMA) containing α‐terminal MS unit, and an Mn of 8.8 × 103?58.5 × 103 with a narrow molecular dispersity index (Mw/Mn = 1.14–1.37). The lack of a need for dilution is due to the fact that an α‐terminal NHCtBu group is acting as the counter cation for the propagating center in the polymerization. From 1H NMR and matrix assisted laser desorption/ionization (MALDI‐TOF) mass spectra, combined with transmittance electron microscope (TEM) observation of a synthesized poly(AMA) with longer alkyl side chains prepared via a thiol‐ene click reaction, it is concluded that once the monomer is consumed, nucleophilic attack at the neighboring methine of the α‐terminal NHCtBu residue by the propagating anionic center causes ring‐closing to cyclic poly(AMA). 相似文献
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Marie Ohata Susumu Fujiwara Ai Yoshioka Hiroshi Nagai Shintaro Sugita Nozomi Yamano Yusuke Inoue Chikako Nishigori 《Pediatric dermatology》2019,36(6):997-998
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy. 相似文献
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N Morikawa K Higuchi T Tsukamoto M Nakano H Terada 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1989,109(11):858-864
Denopamine (DP) is a new, orally active, selectively positive inotropic agent and used for the treatment of chronic cardiac insufficiency. The therapeutic effects of DP is highly related to its serum concentrations. A simple analytical method has been developed to determine the serum concentration of DP by use of high performance liquid chromatography (HPLC) with electrochemical detection (ECD). In order to extract the DP from the serum, a disposable solid extraction column (Sep-Pak cartridge, C-18) was used. The average recovery was 84.6 +/- 2.7%. The working electrode potential was fixed at 400 mV with a T1 cell, 600 mV with a T2 cell and 650 mV with a Guard cell in ECD. The analysis was performed on a Nova-Pak cartridge C-18 reverse-phase column (100 mm X 8 mm i.d., 4 microns). The mobile phase consisted of 0.1 M potassium phosphate buffer (pH 6.0) and acetonitrile (83: 17, v/v), and the flow rate was 1.0 ml/min. DP and internal standard phenolphthalein (PP) were eluted at 16.5 and 36.0 min, respectively. The peak-height ratio of DP to PP was linearly correlated (r = 0.9998) over a concentrations range between 1.25 and 15.0 ng/ml in the serum. The lowest detectable concentration was 1.0 ng/ml in the serum. The coefficient of variation of reproducibility in the assay was 6.0% By using the present method, serum concentration of DP was measured for four healthy volunteers after a single oral administration of 10 mg DP tablet after a overnight fast. From these DP concentration profiles, pharmacokinetic parameters were calculated.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Takahiro Higuchi Stephan G Nekolla Antanas Jankaukas Axel W Weber Marc C Huisman Sybille Reder Sibylle I Ziegler Markus Schwaiger Frank M Bengel 《Journal of nuclear medicine》2007,48(2):288-294
The combination of small-animal PET and MRI data provides quantitative in vivo insights into cardiac pathophysiology, integrating information on biology and morphology. We sought to determine the feasibility of PET and MRI for the quantification of ischemic injury in the rat model. METHODS: Fourteen healthy male Wistar rats were studied with 18F-FDG PET and cine MRI. Myocardial viability was determined in a transmural myocardial infarction model in 12 additional rats, using 18F-FDG PET and delayed-enhancement MRI with gadolinium-diethylenetriaminepentaacetic acid. All PET was acquired with a dedicated small-animal PET system. MRI was performed on a 1.5-T clinical tomograph with a dedicated small-animal electrocardiographic triggering device and a small surface coil. RESULTS: In normal rats, 18F-FDG uptake was homogeneous throughout the left ventricle. The lowest mean uptake of the 18F-FDG was found in the apical regions (79% +/- 6.0% of maximum) and the highest uptake was in the anterior wall (93% +/- 4.3 % of maximum). Myocardial infarct size as determined by histology correlated well with defects of glucose metabolism obtained with 18F-FDG PET (r = 0.89) and also with delayed-enhancement MRI (r = 0.91). Left ventricular ejection fraction in normal rats measured by cine MRI was 57% +/- 5.4% and decreased to 38% +/- 12.9% (P < 0.001) in the myocardial infarction model. CONCLUSION: Integrating information from small-animal PET and clinical MRI instrumentation allows for the quantitative assessment of cardiac function and infarct size in the rat model. The MRI measurements of scar can be complemented by metabolic imaging, addressing the extent and severity of ischemic injury and providing endpoints for therapeutic interventions. 相似文献