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Surface Modification of Carbon Fiber by Photosensitized Oxygenation

Takao Yoshikawa, Akira Kojima, Akaba Ryoichi, Hidetoshi Saito, Sugio Otani
1994 TANSO  
Yoshikawa, Preprints of Int. Symp. on the Development of CF and their Appl., (1990.04) 128.  ... 
doi:10.7209/tanso.1994.230 fatcat:rpishnuqazf53j3qucuyg42ane

A case of Brunner's gland hyperplasia with features of duodenal cancer

Keiichiro Kume, Masahiro Yamasaki, Ryoichi Narita, Ichiro Yoshikawa
2009 Gastroenterology Insights  
A rare case of Brunner's gland hyperplasia mimicking duodenal cancer is reported. A 68year old woman had an elevated lesion in the second portion of the duodenum. Endoscopy after spraying with indigo carmine dye showed a granular appearance and fold convergence. The biopsy specimen suggested hyperplasia without malignancy. However, since the endoscopic features strongly suggested malignancy, endoscopic mucosal resection (EMR) was performed to establish the correct diagnosis. The final pathology diagnosis was Brunner's hyperplasia.
doi:10.4081/gi.2009.e8 fatcat:kp3g6e4kbngpppxf4nmxkq5nx4

Plyometric Training Favors Optimizing Muscle–Tendon Behavior during Depth Jumping

Kuniaki Hirayama, Soichiro Iwanuma, Naoki Ikeda, Ayumi Yoshikawa, Ryoichi Ema, Yasuo Kawakami
2017 Frontiers in Physiology  
The purpose of the present study was to elucidate how plyometric training improves stretch-shortening cycle (SSC) exercise performance in terms of muscle strength, tendon stiffness, and muscle-tendon behavior during SSC exercise. Eleven men were assigned to a training group and ten to a control group. Subjects in the training group performed depth jumps (DJ) using only the ankle joint for 12 weeks. Before and after the period, we observed reaction forces at foot, muscle-tendon behavior of the
more » ... strocnemius, and electromyographic activities of the triceps surae and tibialis anterior during DJ. Maximal static plantar flexion strength and Achilles tendon stiffness were also determined. In the training group, maximal strength remained unchanged while tendon stiffness increased. The force impulse of DJ increased, with a shorter contact time and larger reaction force over the latter half of braking and initial half of propulsion phases. In the latter half of braking phase, the average electromyographic activity (mEMG) increased in the triceps surae and decreased in tibialis anterior, while fascicle behavior of the gastrocnemius remained unchanged. In the initial half of propulsion, mEMG of triceps surae and shortening velocity of gastrocnemius fascicle decreased, while shortening velocity of the tendon increased. These results suggest that the following mechanisms play an important role in improving SSC exercise performance through plyometric training: (1) optimization of muscle-tendon behavior of the agonists, associated with alteration in the neuromuscular activity during SSC exercise and increase in tendon stiffness and (2) decrease in the neuromuscular activity of antagonists during a counter movement.
doi:10.3389/fphys.2017.00016 pmid:28179885 pmcid:PMC5263151 fatcat:f52a5hw6vbhglepdgmdcxt3xli

A Study on Bottleneck Capacity on Divided Two-lane Expressways

Ryoichi YOSHIKAWA, Kazumi NAGAHAMA, Jian XING, Toshio YOSHII, Ryuichi KITAMURA
2005 INFRASTRUCTURE PLANNING REVIEW  
A Study on Bottleneck Capacity on Divided Two-lane Expressways* By Ryoichi YOSHIKAWA**• Kazumi NAG***• Jian XING**** Toshio YOSHII *****• Ryuichi KITAMURA******  ... 
doi:10.2208/journalip.22.839 fatcat:lhxwrc3f6zf47gk5d7y2w44q7y

Convective and periodic motion driven by a chemical wave

Hiroyuki Kitahata, Ryoichi Aihara, Nobuyuki Magome, Kenichi Yoshikawa
2002 Journal of Chemical Physics  
The generation of convective flow by a chemical wave was studied experimentally on a mm-sized droplet of Belousov-Zhabotinsky ͑BZ͒ reaction medium. A propagating chemical wave causes a transient increase in interfacial tension, and this local change in interfacial tension induces convection. The observed flow profile was reproduced with a numerical simulation by introducing the transient increase in interfacial tension to a modified Navier-Stokes equation coupled with a chemical kinetic
more » ... ; a modified Oregonator. We also observed the periodic motion of a BZ droplet floating on an oil phase. Such periodic motion is attributed to the rhythmic change in interfacial tension. The observed periodic convective motion coupled with a chemical reaction is discussed in relation to chemo-mechanical energy transduction under isothermal conditions.
doi:10.1063/1.1456023 fatcat:azjihdhpozf2jlnwfmbhsodwge

A Case of Acute Fatty Metamorphosis of Pregnancy
急性妊娠脂肪肝(acute fatty metamorphosis of pregnancy)の一例

Katsumi MORI, Kunio YOSHIKAWA, Youzaburo AKASHI, Ryoichi TANAKA, Kazuo ONO
1974 Kanzo  
A Case of Acute Fatty Metamorphosis of Pregnancy MORI Katsumi, YOSHIKAWA Kunio, AKASHI Youzaburo, TANAKA Ryoichi* & ONO Kazuo** This disease entity was first proposed by Sheehan in 1940, since  ... 
doi:10.2957/kanzo.15.529 fatcat:ayon3olvnrardmfaxoms7m5ygu

Cardiovascular responses to endotracheal intubation with the Bullard and the Macintosh laryngoscopes

Kazukuni Araki, Ryoichi Nomura, Naohisa Tsuchiya, Yokiko Yoshikawa
2002 Canadian Journal of Anesthesia  
Kazukuni Araki MD Ryoichi Nomura MD Naohisa Tsuchiya MD Yokiko Yoshikawa MD Ohtsu, Japan Positioning the double-lumen endobronchial tube To the Editor: We read with interest an article by Fortier et  ... 
doi:10.1007/bf03017938 pmid:11983676 fatcat:r2sa7nibojdfrcnchfvkf4rj3i

Correlation of the Initial bacterial concentration and detection time in indirect conductimetric assay

JUN SAWAI, RYOICHI DOI, YOSHIKO MAEKAWA, TADASHI YOSHIKAWA, HIROMITSU KOJIMA
2002 Biocontrol Science  
The correlation between bacterial concentration and the change in electrical conductivity was investigated for the indirect conductimetric assay which measures the conductivity change of an alkaline solution (NaOH) that absorbs the CO2 produced by bacterial growth and metabolism. The conductivity of the NaOH solution for a sample containing a higher bacterial concentration changed faster than that for a sample containing a lower concentration, and the logarithmic initial bacterial concentration
more » ... (CB0) was related to the time (tD) , at which the conductivity of the absorbent changed, in a linear fashion. We derived theoretically the validity of the linear relationship and estimated the generation time (tg) from the relationship. The tg values obtained by the indirect conductimetric assay were almost identical to those obtained by the direct conductimetric assay and the Standard Plate Count method.
doi:10.4265/bio.7.43 fatcat:fhlhgttwhrgern6a75r32b52y4

Calcified nodule formation by dental pulp cells derived from rats after subcutaneous injection of an immunosuppressant

Masataka Yoshikawa, Ayano Miyamoto, Ryoichi Ikezawa, Hitomi Nakama, Ikuo Nishikawa, Hiroshi Maeda
2020 Zenodo  
The purpose of this study was to assess the significant proliferation of dental pulp-derived stem cells in vitro from rats with the systemic administration of immunosuppressant in subcutis. There must be a sufficient number of stem cells for tooth regeneration. However, number of mesenchymal stem cells in the dental pulp tissue is a small. Then, the proliferation of stem cells must be accelerated for hard tissue formation. The subcutaneous injection of the immunosuppressant would enhance the
more » ... d tissue forming ability of dental pulp cells of rat. It was hypothesized in this study that differentiation of stem cells into blasts would be effectively promoted by suppression of the systemic immune response. Materials and methods: The dental pulp cells of rats with immunosuppressant injection subcutaneously were cultured with or without addition of the immunosuppressant in the medium containing dexamethasone for calcified nodule formation. Ca2+ by decalcification of calcified nodules were quantitatively analysed. Statistical comparisons between the quantities of Ca2+ were performed using two-way unrepeated ANOVA followed by post hoc analysis with Tukey-Kramer's test. Differences of p < 0.01 were considered significant. Results: The proliferation and differentiation of stem cells among dental pulp cells was inhibited by the presence of immunosuppressive agents in the culture medium. However, stem cells obtained from rats after systemic administration of an immunosuppressive agent exhibited a high ability to form calcified nodules. Conclusions: To promote proliferation and differentiation of stem cells, systemic administration of an immunosuppressant to individuals prior to harvesting stem cells would be recommended.
doi:10.5281/zenodo.4318126 fatcat:l5rhxkrezrcchkh23py7ekcykm

Experimental system for measurement of radiologists' performance by visual search task

Eriko Maeda, Takeharu Yoshikawa, Ryoichi Nakashima, Kazufumi Kobayashi, Kazuhiko Yokosawa, Naoto Hayashi, Yoshitaka Masutani, Naoki Yoshioka, Masaaki Akahane, Kuni Ohtomo
2013 SpringerPlus  
Purpose: Detective performance of radiologists for "obvious" targets should be evaluated by visual search task instead of ROC analysis, but visual task have not been applied to radiology studies. The aim of this study was to set up an environment that allows visual search task in radiology, to evaluate its feasibility, and to preliminarily investigate the effect of career on the performance. Materials and methods: In a darkroom, ten radiologists were asked to answer the type of lesion by
more » ... g buttons, when images without lesions, with bulla, ground-glass nodule, and solid nodule were randomly presented on a display. Differences in accuracy and reaction times depending on board certification were investigated. Results: The visual search task was successfully and feasibly performed. Radiologists were found to have high sensitivity, specificity, positive predictive values and negative predictive values in non-board and board groups. Reaction time was under 1 second for all target types in both groups. Board radiologists were significantly faster in answering for bulla, but there were no significant differences for other targets and values. Conclusion: We developed an experimental system that allows visual search experiment in radiology. Reaction time for detection of bulla was shortened with experience.
doi:10.1186/2193-1801-2-607 pmid:24294550 pmcid:PMC3838537 fatcat:tcouobywbrakncgewttnk4ptku

A Citrus Flavonoid Hesperidin Suppresses Infection-Induced Endotoxin Shock in Mice

Kiichiro Kawaguchi, Sei-ichi Kikuchi, Ryoichi Hasunuma, Hiroko Maruyama, Takafumi Yoshikawa, Yoshio Kumazawa
2004 Biological and Pharmaceutical Bulletin  
Septic shock caused by Gram-negative bacteria is initiated by lipopolysaccharide (LPS), the main constituent of the outer membrane, and triggered by TNF-a which is a main representative among various types of cytokines produced by LPS-stimulated macrophages. 1-3) Thus, screenings for substances capable of inhibiting endotoxin shock have mainly focused on the suppression of TNF-a production. An inhibitory substance(s) from cinnamon bark has recently been shown to reduce TNF-a release by directly
more » ... binding to the lipid A moiety of LPS. 4) In a previous study, 5) we showed that naringin, the main flavonoid of grapefruit, suppressed LPS-induced TNF-a production. Since sensitization with Dgalactosamine (GalN) renders mice hypersensitive to TNF-a released by LPS-stimulated macrophages, 6,7) the inhibitory effect of naringin on lethal shock could convincingly be demonstrated in GalN-sensitized mice. 5) Hesperidin (HES), a common constituent of citrus fruits, possesses significant inhibitory activities on inflammation, hypotension and analgesia, 8-10) colony stimulating factor-inducing activity, 11) nitric oxide synthase inhibition, 12) and antiapoptotic efficacy. 13) Recently we established a new endotoxin shock model based on intraperitoneal (i.p.) infection with high numbers (10 8 CFU) of attenuated Salmonella typhimurium and compared the effect of the antibiotics fosfomycin and imipenem. 14) We describe in this study that pretreatment with HES, capable of reducing both LPS-elicited and infection-induced TNF-a production, inhibited infection-induced lethal shock, which resembles clinical cases. MATERIALS AND METHODS Mice Female BALB/c and C57BL/6 (B6) mice were purchased from Clea Japan Inc. (Tokyo, Japan). Breeding pairs of BALB/lps d mice were obtained from the Max-Planck-Institute for Immunobiology (Freiburg in Breisgau, Germany). All mice were kept at the animal facility of the Kitasato University School of Science under specific pathogen free conditions and fed autoclaved food and water.
doi:10.1248/bpb.27.679 pmid:15133244 fatcat:nznddck2bbcijewtj4xbvbt44a

Surgical Treatment Using Tailoring Technique for Renal Artery Aneurysm

Shinichi Imai, Ryoichi Kyuragi, Masahiro Yoshikawa, Naotaka Sakamoto, Toshihiro Onohara
2019 The Journal of Japanese College of Angiology  
doi:10.7133/jca.19-00018 fatcat:k3xkjnxbord4nduaetiprkmgbu

Bronchial cuff pressure change caused by left-sided double-lumen endobronchial tube displacement

Kazukuni Araki, Ryoichi Nomura, Reiko Urushibara, Yukiko Yoshikawa, Yoshio Hatano
2000 Canadian Journal of Anesthesia  
REPORTS OF INVESTIGATION 775 CAN J ANESTH 2000 / 47: 8 / pp [775][776][777][778][779] Purpose: The bronchial cuff pressures (BCPs) of left-sided double-lumen endobronchial tubes (DLTs) manufactured by Rüsch and Mallinckrodt were measured in 80 patients when the tubes were withdrawn to compare the effect of tube design on BCP change. Methods: During general anesthesia with muscle relaxation, the cephalad surface of the endobronchial cuff was positioned either 2.5 cm distal to the carina (Rüsch
more » ... oup R-I; n = 20 and Mallinckrodt Group B-I; n = 20) or just below the carina (Rüsch Group R-II; n = 20 and Mallinckrodt Group B-II; n = 20) and the cuff was inflated to 35 cm H 2 O. The tube was then withdrawn in 0.5-cm steps until the cuff was 2.0 cm proximal to the carina, the position just before the capnogram or pressure-volume loop of tracheal lumen changed. The BCP at each step was measured. The rate of decrease in BCP was defined as the decrease of BCP divided by the length of displacement of DLT. Results: The rates of decrease from the +2.5 cm position to the end point in Group B-I (7.7 ± 0.8 cm H 2 O·cm -1 ) and those from the most proximal acceptable position to the end point in Group B-II (19.5 ± 4.8 cm H 2 O·cm -1 ) were greater than those in Group R-I (6.9 ± 0.9 cm H 2 O·cm -1 ) (P < 0.01) and in Group R-II (12.4 ± 3.1 cm H 2 O·cm -1 ) (P < 0.01), respectively. Conclusion: The BCP decreased in both of the Mallinckrodt and Rüsch DLTs, and the rates of decrease of the former were greater than those of the latter. Objectif : Les pressions du ballonnet bronchique (PBB) des tubes à double lumière (TDL) gauches fabriqués par Rüsch et Mallinckrodt ont été mesurées chez 80 patients au moment du retrait des tubes afin de comparer l'effet du design du tube sur le changement de PBB.
doi:10.1007/bf03019480 pmid:10958094 fatcat:s3bozzx5cram3dhfvpauwip54i

Temporal Characteristics of Radiologists' and Novices' Lesion Detection in Viewing Medical Images Presented Rapidly and Sequentially

Ryoichi Nakashima, Yuya Komori, Eriko Maeda, Takeharu Yoshikawa, Kazuhiko Yokosawa
2016 Frontiers in Psychology  
Copyright © 2016 Nakashima, Komori, Maeda, Yoshikawa and Yokosawa. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).  ... 
doi:10.3389/fpsyg.2016.01553 pmid:27774080 pmcid:PMC5054019 fatcat:gxjzq2xr2zbv5ir4hxargv6gim

Recent results from EUVL patterned mask inspection using projection electron microscope system

Ryoichi Hirano, Susumu Iida, Tsuyoshi Amano, Tsuneo Terasawa, Hidehiro Watanabe, Masahiro Hatakeyama, Takeshi Murakami, Shoji Yoshikawa, Kenji Terao, Paul W. Ackmann, Naoya Hayashi
2014 Photomask Technology 2014  
Acknowledgement The authors would like to thank the following people from Toshiba Corporation: Masato Naka, Ryoji Yoshikawa, Takashi Hirano, and Masamitsu Itoh; the following people from EBARA CORPORA-TION  ... 
doi:10.1117/12.2066134 fatcat:rh4pqpb5rndcnckttgsfwdd53q
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