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51.
Iida K Inagaki Y Todo H Okamoto H Danjo K Luenberger H 《Chemical & pharmaceutical bulletin》2004,52(8):938-942
The effects of the surface processing of lactose carrier particles on the dry powder inhalation properties of salbutamol sulfate were investigated. Lactose carrier particles were processed using a high-speed elliptical-rotor-type powder mixer (Theta-Composer). In the present study, drug/carrier powder mixtures were prepared, consisting of micronized salbutamol sulfate and coarse lactose carriers with various particle surface conditions prepared by surface processing. These powder mixtures were aerosolized by a Jethaler, and the in vitro inhalation properties of salbutamol sulfate were evaluated with a twin impinger. Compared with those of the powder mixed with unprocessed lactose carriers, the in vitro inhalation properties of the powder mixture prepared using the surface processed lactose carriers were significantly different, showing that the in vitro inhalation properties of salbutamol sulfate were improved. The in vitro inhalation properties increased with the rotor rotation rate. Using this surface processing system would thus be valuable for increasing the inhalation properties of dry powder inhalation with lactose carrier particles. 相似文献
52.
Wataru NAKANO Satomi KOBAYASHI Takayuki MAEZAWA Yukari OHASHI Yutaka KOHNO 《Physical Therapy Research》2021,24(3):280
OBJECTIVE: Adequate physical activity after stroke is critical for cardiovascular health. Although sex is a potential factor associated with post-stroke physical activity, its mechanism remains unclear. This study aimed to examine sex differences in human physical activity following stroke. METHOD: A cross-sectional study with 62 participants (men: 42, women: 20) was conducted. Physical activity was measured for three consecutive days using a step activity monitor. The walking durations per day in light physical activity, moderate-to-vigorous physical activity, and total physical activity were calculated. Sex differences in walking duration were compared using Welch''s t-tests or Mann-Whitney U tests. RESULTS: Women had a significantly greater walking duration in light physical activity and in total than did the men. In contrast, no significant differences were found in moderate-to-vigorous physical activity. CONCLUSION: This study reported sex differences in the walking duration after stroke. Moreover, it found that women spent more time in low intensity physical activity than men. Our results will be useful for planning interventions to increase physical activity and decrease sedentary behavior after stroke. 相似文献
53.
Yukari Tajika Yumi Yasuoka Hiroyuki Nagahama Toshiyuki Suzuki Yoshimi Homma Tetsuo Ishikawa Shinji Tokonami Takahiro Mukai Miroslaw Janik Atsuyuki Sorimachi Masahiro Hosoda 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):1709-1714
Gas-flow ionization chambers for radioisotope (RI) monitoring systems at RI institutes throughout Japan are commonly used to measure RIs which leak from the RI institutes. Before the Japan’s 2011 Tohoku earthquake [11 March 2011, moment magnitude (M w) 9.0], ionization current data measured with a gas-flow ionization chamber at the RI institute of Fukushima Medical University were found to change. The question we must raise is whether the variation ionization current can be considered to the variation of outdoor radon concentration. The conversion factors (from ionization current to radon concentration in air) of the gas-flow ionization chamber can be obtained by measuring four levels of radon concentration (outdoor air, indoor air, high level and radon-free gas) with an AlphaGUARD monitor and the chamber itself. The two gas-flow ionization chambers consist of the air intake and terminal exhaust duct of the RI institute. It was found that the radon concentration in the exhaust air was the same as that in the air intake. This study provided evidence that variations of outdoor radon concentration could be determined using gas-flow ionization chambers for RI monitoring systems. 相似文献
54.
Mizutani F Yabuki S Sato Y Iijima S 《Bioelectrochemistry (Amsterdam, Netherlands)》2004,63(1-2):257-259
An enzyme electrode with a chemically amplified response for methylene blue (MB) was constructed from a glassy carbon electrode and a layer containing immobilized horseradish peroxidase (HRP). MB is reduced on the electrode but regenerated through the HRP-catalyzed reaction in the presence of H(2)O(2). The electroreduction/regeneration cycle for MB resulted in an amplified electrode response. The enzyme electrode was applied to the highly sensitive measurement of ds-DNA. The current for MB decreased in association with its complexation with DNA, and the current response caused by DNA was also amplified through the recycling processes. The detection limit of ds-DNA (from salmon testes) was as low as 5 ng ml(-1). 相似文献
55.
Shigeru Arai Keiji Nakayama Yukari Suzuki Kei-ichiro Hatano Takayuki Shioiri 《Tetrahedron letters》1998,39(52):2459-9742
Treatment of cyclic or acyclic -haloenones with various carbon nucleophiles involving active methylene functions afforded the corresponding dihydrofurans in a stereoselective manner with good to high yields. This reaction system can provide a general and practical methodology for the construction of dihydrofuran rings. 相似文献
56.
Swelling behaviors of poly(vinyl alcohol) (PVA) gel were investigated in solutions of salts containing certain divalent ions, namely, alkaline-earth-metal halides and sulfates of alkali-metals, alkaline-earth-metals, and transition metals. The gel deswelled in the solutions of the alkaline-earth-metal chlorides but swelled in those of the bromides. However, the cation specificities of the swelling for both of the halides were roughly the same: the degrees of swelling are Sr2+2+2+. The gel deswelled for all sulfate solutions with specificities for alkali-metal and alkaline-earth-metal cations: the swelling degrees are K+;Na+2++. There was no order for transition metals. 相似文献
57.
Feng Gao Huijuan Zhao Yukari Tanikawa Kazhuhiro Homma Yukio Yamada 《Optical and Quantum Electronics》2005,37(13-15):1287-1304
Our recent diffuse optical tomography experiments on human lower legs and forearms are presented using the time-resolved measuring system and image reconstruction algorithm based on the modified generalized pulse spectrum technique. It was shown that the spatial resolution and quantitativeness of the resultant images, was rather poor, and the interior blood vessels invisible in the absorption images. To clarify this issue, the influences of target contrast and size on the image reconstruction were investigated with simulated data. We have found that the quantitativeness of the reconstructed optical properties was prone to be spoiled by the small size ratio and high contrast of the interior targets to the background, and the incompleteness of information embedded in the featured data-types, evidently answers for the degradation of the image quality. It was shown in a further simulative investigation that the image quality could be substantially improved by making full use of the time-resolved data. 相似文献
58.
Chemical forms of arsenic were examined in six tissues (gill, mid-gut gland, siphon, foot, mantle and adductor muscle) of the clam Meretrix lusoria. The gill was found to contain higher levels of arsenic than the other tissues. Regardless of the nature of the tissues, the presence of arsenobetaine was established by HPLC0ICP; it was a minor arsenic compound in gill but a major one in the other tissues. The major arsenic compound in gill, which was more cationic than arsenobetaine, was obtained in a relatively pure state by ion-exchange chromatography, gel filtration and HPLC. It was positive to the Dragendorff reagent and iodine vapor but negative to ninhydrin reagent. Its 1HNMR spectrum exhibited only one signal at δ 1.7 (singlet) and its FAB mass spectrum gave a base peak at m/e 135 [(CH3)4As+] and two significant peaks at m/e 120 [(CH3)3As] and 106 [(CH3)2AsH]. These results suggested that the major arsenic compound in gill exists as a tetramethylarsonium salt (CH3)4As+ · X?. The tetramethylarsonium salt was also found as a minor component in the tissues other than the gill. 相似文献
59.
Takeshi Inoue Takeshi Furukawa Akihiro Yoshimi Tsubasa Nanao Masatoshi Chikamori Kunifumi Suzuki Hironori Hayashi Hirokazu Miyatake Yuichi Ichikawa Masato Tsuchiya Naoto Hatakeyama Sota Kagami Makoto Uchida Hideki Ueno Yukari Matsuo Takeshi Fukuyama Koichiro Asahi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2016,70(6):129
60.
Yamano Y Fujita Y Mizuguchi Y Nakagawa K Okano T Ito M Wada A 《Chemical & pharmaceutical bulletin》2007,55(9):1365-1370
An improved synthesis of gamma-hydroxybutenolides 1a-d was achieved via crossed aldol condensation between aldehydes 2a-d and the protected gamma-hydroxy-beta-methylbutenolides 3 or 4 using the bulky Lewis acid, aluminum tris(2,6-diphenylphenoxide) (ATPH). Using this same methodology, the gamma-hydroxybutenolides 17a-d having various heteroaromatic rings were synthesized and their anti-tumor activities were evaluated. 相似文献