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Publication
Featured researches published by Yasushi Kobayashi.
World Journal of Surgery | 1998
Shigetaka Yamamoto; Yoshio Yamasaki; Keiji Kuwata; Hajime Yamasaki; Yukihiro Nishida; Yasushi Kobayashi
Abstract. We studied the relation betweenHelicobacter pylori and residual gastritis in 28 patients with gastric cancer on whom distal partial gastrectomy with Billroth I reconstruction was performed over a 13-month period. They were subjected to serologic testing along with endoscopic and histologic examinations before operation and at 3, 6, and 12 months after operation. Anti-H. pylori immunoglobulin G (IgG) and serum gastrin levels were measured by serologic tests. The presence or absence of gastritis was determined endoscopically, and gastric mucosal hexosamine levels were determined. Gastritis was measured quantitatively by histologic examination in specimens taken from the gastric mucosa using Rauws’ score. After the initial histologic evaluation we divided the H. pylori-positive patients into two groups: those with a Rauws’ score of 0 to 3 (“weak” gastritis group), and those with a Rauws’ score of 4 to 10 (“strong” gastritis group), allowing us to compare the results of our three postoperative histologic examinations of the two groups for possible significant differences. Our endoscopic examinations showed gastric mucosal inflammatory changes in both H. pylori-positive andH. pylori-negative patients at 3, 6, and 12 months after operation, but there was no significant difference between these two groups at any point. During the histologic examinations, however, anti-H. pylori IgG assay had become negative in several patients in the “weak” gastritis group at 3 months after operation and was found to have become negative in 78% of all patients in that group 12 months after operation. In contrast, in the “strong” gastritis group H. pylori infection was still evident in the patients 12 months after operation, suggesting that “strong” histologic gastritis may have some connection to H. pyloriinfection, whereas “weak” histologic gastritis has no such connection. The gastric mucosal hexosamine level was higher in the “weak” gastritis group than in the “strong” gastritis group both before operation and at 6 and 12 months, indicating some relation between gastric inflammatory changes and hexosamine levels in gastric mucosa. It further suggested the possibility that H. pyloriplays a role in destroying gastric mucosa by depleting mucin, thus acting as one (though not the only) cause of residual gastritis after distal partial gastrectomy. In conclusion, we found evidence that there is a relation between residual gastritis and H. pyloriinfection, but H. pylori is not the sole cause of residual gastritis after gastric surgery. A causal relation is difficult to detect by simple analysis of histologic findings or by endoscopic observation or clinical symptoms alone.
Surgery Today | 1997
Tokio Yamaguchi; Masahiko Miyata; Wataru Kamiike; Yasushi Kobayashi; Hikaru Matsuda
To clarify the histological status of the pancreas tail after pancreatoduodenectomy (PD), fibrosis, islets of Langerhans, and A, B, and D cells were examined histometrically in surgical cases of pancreatic cancer. The same investigations were also performed during an autopsy examination of the pancreas tail of survivors of surgery who had received either PD or total pancreatectomy with segmental autotransplantation (SAT). In the surgical cases, fibrosis and the islet percentage compared with nonpancreatic cancer cases were significantly higher while the B cell ratio was significantly lower. In addition, in pancreatic cancer patients, the fibrosis and islet ratio in the group with a blocked pancreatic duct were higher while the B cell ratio was lower than in the group with an open pancreatic duct. A direct relationship between the islet ratio and the degree of fibrosis, and an inverse relationship between the B cell ratio and the degree of fibrosis, were thus found. From the autopsy cases, the fibrosis progressed and the islet ratio increased following PD, but after SAT only the islet ratio increased compared to the time of surgery. The progression of fibrosis after PD thus suggests the presence of some problems in both the surgical method and postoperative management.
Archive | 1977
Yasushi Kobayashi; Akira Ito
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 2001
Hiroshi Komoda; Yoshio Yamasaki; Yuichi Fukui; Taihei Kou; Yasushi Kobayashi; Keiji Kuwata
Kanzo | 1989
Tetsuo Takehara; Hiroyuki Matsuda; Masahumi Naitou; Hitoshi Sawaoka; Hougen Kin; Masayoshi Azuma; Natsuki Mitsutani; Takeo Koizumi; Shirou Sakamoto; Keiji Kuwata; Tokio Yamaguchi; Yasushi Kobayashi
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 1998
Kazuhiko Nishizaki; Yoshio Yamasaki; Keiji Kuwata; Tetsuya Matsushita; Yasushi Kobayashi
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 1996
Chun Man Lee; Keiji Kuwata; Yoshio Yamasaki; Kiyoshi Ohno; Hajime Yamazaki; Shigetaka Yamamoto; Hiroyuki Nishida; Taichi Sakaguchi; Yasushi Kobayashi
Archive | 2007
Ken Shiozaki; Masashi Baba; Toshio Kanai; Yasushi Kobayashi; Tadao K. Kobayashi; Motohisa Takami
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 2007
Ken Shiozaki; Masashi Baba; Toshio Kanai; Yasushi Kobayashi; Motohisa Takami
Nihon Rinsho Geka Gakkai Zasshi (journal of Japan Surgical Association) | 2002
Akio Hayashi; Yoshio Yamasaki; Masahiro Ryugo; Hajime Yamasaki; Keiji Kuwata; Yasushi Kobayashi