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Dive into the research topics where Hitoshi Okawara is active.

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Featured researches published by Hitoshi Okawara.


Gastrointestinal Endoscopy | 2010

Endoscopic closure of a large ERCP-related lateral duodenal perforation by using endoloops and endoclips

Yoshifumi Nakagawa; Takayuki Nagai; Wataru Soma; Hitoshi Okawara; Hiroshi Nakashima; Takako Tasaki; Akari Hisamatu; Masahiko Hashinaga; Kazunari Murakami; Toshio Fujioka

An 88-year-old man with recurrent obstructive jaundice esulting from common bile duct cancer underwent ERCP. he patient’s medical history included a cholecystectomy years earlier and 4 episodes of obstructive jaundice ecause of biliary stent occlusion. At insertion of a duoenoscope into the duodenum, a perforation measuring bout 30 mm occurred in the lateral wall of the descending uodenum (Fig. 1A). The patient was inoperable because f advanced age and comorbidities. After informed conent was obtained, we tried endoscopic repair of this erforation. Closure with endoclips alone failed because he hole was too large. We decided to close the perforaion with endoloops (MAJ-254; Olympus Optical Co Ltd, okyo, Japan) and endoclips (HX-610-090; Olympus) by sing a 2-channel endoscope (GIF-2TQ260M; Olympus) ith a distal attachment (disposable distal attachment, -201-13404; Olympus). The 2-channel endoscope alowed simultaneous insertion of an endoloop and an enoclip applicator device (HX-110QR/HX-610-090; Olymus). By using the endoclip, we anchored the endoloop


Esophagus | 2011

Difference between urban and rural regions in Japan in estimated risk of esophageal cancer based on a health risk appraisal model that includes an alcohol flushing questionnaire

Yoshifumi Nakagawa; Akira Yokoyama; Takayuki Nagai; Hitoshi Okawara; Hiroshi Nakashima; Kayo Soga; Kazunari Murakami; Toshio Fujioka; Yoshiya Kumagai; Masako Yokoyama; Tetsuji Yokoyama

BackgroundMany environmental and genetic factors are presumed to be involved in the etiology of esophageal squamous cell carcinoma (ESCC). We developed a health risk appraisal model that includes an alcohol flushing questionnaire (HRA-F) to estimate the ESCC risk. The purpose of this study was to use the HRA-F model to assess regional differences in the ESCC risk between rural and urban regions in Japan.MethodsWe compared the HRA-F scores for risk of ESCC of 1,043 medical screening examinees (442 men and 601 women) in a rural region of Oita Prefecture and 1,016 medical screening examinees (610 men and 406 women) in a central region of Tokyo, Japan.ResultsAfter adjustment for age, there was no difference between the frequencies of current or former facial flushers in the two populations. Oita men consumed more alcohol than Tokyo men, but Oita women consumed less alcohol than Tokyo women. There was no difference between Oita and Tokyo in the suppressive effect of flushing on alcohol consumption. Oita individuals of both genders reported less smoking, lower green and yellow vegetable intake, and lower fruit intake than did Tokyo individuals. The risk of ESCC quantitatively assessed based on the HRA-F scores was higher in Oita men than in Tokyo men, but a higher proportion of women were at high risk in Tokyo than in Oita.ConclusionThe HRA-F model was useful for identifying regional differences in ESCC risk and persons at high risk of ESCC in the Japanese population.


Internal Medicine | 2004

Spontaneous dissection of the superior mesenteric artery in four cases treated with anticoagulation therapy.

Takayuki Nagai; Ryutaro Torishima; Akihiro Uchida; Hiroshi Nakashima; Kenji Takahashi; Hitoshi Okawara; Masatoshi Oga; Koji Suzuki; Shinji Miyamoto; Ryugo Sato; Kazunari Murakami; Toshio Fujioka


Internal Medicine | 2010

Gastritis associated with Epstein-Barr virus infection.

Akari Hisamatsu; Takayuki Nagai; Hitoshi Okawara; Hiroshi Nakashima; Takako Tasaki; Yoshifumi Nakagawa; Masahiko Hashinaga; Shunichi Kai; Shigeo Yokoyama; Kazunari Murakami; Toshio Fujioka


Internal Medicine | 2004

Spontaneous Esophageal Submucosal Hematoma in which the Course could be Observed Endoscopically

Takayuki Nagai; Ryutarou Torishima; Hiroshi Nakashima; Akihiro Uchida; Hitoshi Okawara; Koji Suzuki; Ryugo Sato; Kazunari Murakami; Toshio Fujioka


Internal Medicine | 2009

Pancreatic Injury Successfully Treated with Endoscopic Stenting for Major Pancreatic Duct Disruption

Takashi Abe; Takayuki Nagai; Kazunari Murakami; Juro Anan; Masahiro Uchida; Hideki Ono; Hitoshi Okawara; Jin Tanahashi; Tadayoshi Okimoto; Masaaki Kodama; Toshio Fujioka


Internal Medicine | 2009

Cap polyposis (CP) which relapsed after remission by avoiding straining at defecation, and was cured by Helicobacter pylori eradication therapy.

Yoshifumi Nakagawa; Takayuki Nagai; Hitoshi Okawara; Hiroshi Nakashima; Takako Tasaki; Wataru Soma; Akari Hisamatsu; Masahide Watada; Kazunari Murakami; Toshio Fujioka


Endoscopy | 2009

Comparison of magnified endoscopic images of Ancylostoma duodenale (hookworm) and Anisakis simplex.

Yoshifumi Nakagawa; Takayuki Nagai; Hitoshi Okawara; Hiroshi Nakashima; Takako Tasaki; Wataru Soma; A. Hisamatu; J. Anan; K. Murakami; Toshio Fujioka


Internal Medicine | 2013

Long-term Follow-up of Gastric Adenocarcinoma with Chief Cell Differentiation Using Upper Gastrointestinal Tract Endoscopy

Takashi Abe; Takayuki Nagai; Junji Fukunaga; Hitoshi Okawara; Hiroshi Nakashima; Mitsutaka Syutou; Nobuaki Kajimoto; Ryojin Wake; Tsuneo Oyama; Takashi Yao


Endoscopy | 2011

Acute hemorrhagic colitis induced by the oral administration of oseltamivir used for influenza A treatment.

Yoshifumi Nakagawa; Takayuki Nagai; Hitoshi Okawara; Hiroshi Nakashima; Akari Hisamatsu; Mitsutaka Shuto; M. Yamauchi; Shunichi Kai; Shigeyuki Yokoyama; K. Murakami; Toshio Fujioka

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Hiroshi Nakashima

Brigham and Women's Hospital

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