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101.
102.
103.
Kose Segawa M.D. Saburo Nakazawa M.D. Yoshihisa Tsukamoto M.D. Hidemi Goto M.D. Kenji Yamao M.D. Satoshi Hase M.D. Toshimasa Osada M.D. Tomiyasu Arisawa M.D. 《The American journal of gastroenterology》1988,83(4):373-379
We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis. 相似文献
104.
Kazuichi Okazaki Yasuro Yamamoto Isao Nishimori Takami Nishioka Soichi Kagiyama Satoru Tamura Yoshiya Sakamoto Yoshihiko Nakazawa Masanori Morita Yasutake Yamamoto 《The American journal of gastroenterology》1988,83(8):820-826
We endoscopically measured pressures of the pancreatic duct (PP) and the sphincter of Oddi (SO) in patients with alcoholic (ALCP, n = 10), gallstone-associated (GSCP, n = 7), and idiopathic chronic pancreatitis (ICP, n = 21), and in 20 controls. The PP was significantly higher in the patients with ALCP (55.7 +/- 28.9 mm Hg), GSCP (33.6 +/- 16.2 mm Hg), or ICP (44.5 +/- 25.8 mm Hg) than in the controls (16.2 +/- 8.7 mm Hg), but there was no significant difference between ALCP, GSCP, and ICP. There was no significant difference between control subjects and ICP in the motility of SO. In ICP, there was no correlation between the PP and the motility of SO. In ALCP and GSCP, the frequencies of the papillary sphincter waves were significantly higher than in normal subjects, and there were correlations between the PP and the motility of SO. These data suggest that increased pancreatic ductal pressure in GSCP with papillitis or ALCP may be due in part to papillary dysfunction, but not in ICP. 相似文献
105.
Hiroi H Momoeda M Nakazawa F Koizumi M Tsutsumi R Hosokawa Y Osuga Y Yano T Tsutsumi O Taketani Y 《Endocrine journal》2008,55(1):183-189
Periostin/OSF2 is a ligand for alphavbeta3 and alphavbeta5 integrins and activates the Akt/PKB pathway. Recent reports of periostin/OSF2 gene disrupted mice indicate that periostin/OSF-2 plays an important role in implantation. Quantitative RT-PCR revealed that the expression of periostin/OSF-2 mRNA in rat uteri was reduced to approximately 10% at 12 h after 17beta-estradiol (E2) injection, but was not changed after progesterone (P) injection. RT-PCR revealed the expression of periostin/OSF-2 in human endometrium, cultured human endometrial stromal cells (ESCs), and cultured human endometrial epithelial cells. In ESCs, the expression of periostin/OSF-2 mRNA was reduced to approximately 50% at 6 h after E2 treatment. The amount of periostin/OSF2 mRNA in human endometrium significantly increased during mid-proliferative and early secretory phases of menstrual cycle, and decreased during late-proliferative, mid-secretory and late secretory phases. The expression of periostin/OSF2 mRNA significantly decreased in ESCs decidualized by treatment with E2 and P for 7 and 11 days. By immunohistochemistry, the expression of periostin/OSF-2 was strongly detected in endometrial stromal cells during early proliferative, mid-proliferative and early secretory phases, and was strongly detected in endometrial epithelial cells during late secretory phase. This study demonstrated that the expression of periostin/OSF-2 is regulated by ovarian steroid hormones in rat uterus and human endometrium. 相似文献
106.
Transmission of Helicobacter pylori from Challenged to Nonchallenged Nude Mice Kept in a Single Cage
Yoshimatsu T Shirai M Nagata K Okita K Nakazawa T 《Digestive diseases and sciences》2000,45(9):1747-1753
To determine the transmission route of Helicobacter pylori, one nude mouse was challenged by H. pylori, and then raised with nonchallenged nude mice in a single cage in a sterilized environment with and without exposure to their feces. After coraising for two and four weeks, all mice were killed to determine H. pylori in the stomach, saliva, and feces and to assess gastritis grade. Natural transmission of H. pylori occurred in 50% (2/4) and 70% (7/10) of mice after two weeks and four weeks of coraising when they were exposed to their feces. H. pylori was detected not only in the stomach but also in saliva and feces by PCR of all challenged and transmitted mice. However, no transmission occurred in mice not exposed to feces of a challenged mouse, while sharing food and water in a single cage. These findings suggest that the fecal–oral transmission route is important, at least in the animal model. Serum levels of anti-H. pylori urease IgG of the H. pylori-transmitted mice increased after coraising, and gastritis was observed in the stomach of both challenged and transmitted mice. We conclude that H. pylori bacteria are transmitted through the fecal–oral route from challenged to nonchallenged nude mice, resulting in gastritis. 相似文献
107.
Takao Nishizawa Mitsunori Iwase Hiroaki Kanazawa Sahoko Ichihara Gaku Ichihara Kohzo Nagata Koji Obata Kiyoyuki Kitaichi Toyoharu Yokoi Masato Watanabe Takashi Tsunematsu Yoshihiro Ishikawa Toyoaki Murohara Mitsuhiro Yokota 《Circulation journal》2004,68(11):1051-1060
BACKGROUND: The relationship between enhanced myocardial oxidative stress and impaired beta-adrenergic signaling remains to be characterized during the development of dilated cardiomyopathy. METHODS AND RESULTS: Alterations in myocardial oxidative stress and beta-adrenergic signaling, as well as left ventricular (LV) functional and structural changes, were evaluated during the development of cardiomyopathy in TO-2 hamsters; F1B hamsters served as controls. LV dysfunction was first apparent at 8 weeks of age and deteriorated thereafter in the TO-2 hamsters. At 32 weeks, the animals exhibited heart failure with an increased plasma norepinephrine concentration. Cardiac myolysis, as demonstrated by elevated plasma concentration of cardiac troponin T, peaked at 8 weeks. The glutathione redox ratio revealed increased oxidative stress in the LV myocardium in TO-2 hamsters even at 4 weeks and became manifest after 8 weeks. The hearts of TO-2 hamsters had significantly reduced superoxide dismutase activity from 8 weeks onward compared with control hamsters. However, glutathione peroxidase activity was unchanged at any time point. The LV functional response to isoproterenol was markedly reduced at 8 weeks, without any apparent changes in the amount of beta-adrenergic signaling molecules, and it deteriorated thereafter. Adenylyl cyclase activity was significantly decreased, despite increased amounts of both G(s) alpha mRNA and protein, in the LV myocardium at 18 weeks. CONCLUSIONS: Myocardial oxidative stress is actually enhanced in the initial development of LV dysfunction. Both activation of myocardial oxidative stress and impairment of beta-adrenergic signaling become prominent at the stage of severe LV dysfunction. Myocardial oxidative stress may be involved in the development of beta-adrenergic desensitization. 相似文献
108.
Hyperthyroidism and the management of atrial fibrillation. 总被引:5,自引:0,他引:5
Taeko Shimizu Saori Koide Jaduk Yoshimura Noh Kiminori Sugino Kohichi Ito Hiroe Nakazawa 《Thyroid》2002,12(6):489-493
Atrial fibrillation is often induced in patients with hyperthyroidism and may trigger heart failure. Its prevalence and outcome were examined to obtain up-to-date information. Persistent atrial fibrillation was observed in approximately 1.7% of new hyperthyroid patients. It occurs more frequently in males (2.86%) than in females (1.36%), even though the number of male hyperthyroid patients is only one fifth of female patients. The rate increased with age, being 8% in the patients older than 70 years old. The initial treatment is to control the heart rate with routine pharmacologic therapy and to start antithyroid therapy as quickly as possible. Attempted cardioversion should be deferred until approximately the fourth month of maintaining a euthyroid state, because more than 56% of atrial fibrillation spontaneously reverts to sinus rhythm when the thyroid hormone levels start to decline. Elective cardioversion for those whose atrial fibrillation persists is highly effective and sinus rhythm maintenance rates were 56.7% and 47.6% at the 10th and the 14th year, respectively, even though the duration of atrial fibrillation prior to cardioversion was extremely long (35.0 +/- 29.0 months). 相似文献
109.
Effect of omeprazole on gastric acid secretion in rat: evaluation of dose, duration of effect, and route of administration 总被引:1,自引:0,他引:1
K Segawa S Nakazawa Y Tsukamoto C Chujoh K Yamao S Hase 《Gastroenterologia Japonica》1987,22(4):413-418
The effect of omeprazole on gastric acid output was studied in rats before and during stimulation by continuous administration of tetragastrin at 50 micrograms/kg-hour. From 5 to 20 mg/kg of omeprazole was given to animals intraperitoneally, perorally and intravenously from 2 to 24 hours before the gastric secretory study was started, and the respective effects on acid secretion were compared. In each administration group, 20 mg/kg of omeprazole was the most potent among the groups receiving 5, 10 or 20 mg/kg, when the drug was given 2 hours before the study. There were statistically significant differences between the control group given tetragastrin only and each of the groups given 20 mg/kg of omeprazole perorally, intraperitoneally and intravenously. There was no significant difference among the groups given 20 mg/kg of omeprazole intraperitoneally, intravenously and perorally. The effect of 20 mg/kg of omeprazole continued at least 24 hours after the agent was administered perorally. 相似文献
110.
M Seguchi T Nakanishi M Nakazawa S Doi K Momma A Takao Y Imai C Kondoh M Hiroe 《European heart journal》1990,11(3):213-218
Postoperative myocardial perfusion and function were evaluated using thallium-201 myocardial imaging and technetium-99m cardiac pool imaging in five patients with an anomalous left coronary artery arising from the pulmonary artery. The patients underwent reimplantation of the left coronary artery at an age ranging from 10 months to 13 years. Postoperative electrocardiographic and radionuclide studies were performed both at rest and during stress 1 to 4 years after the operation. Electrocardiograms which were abnormal preoperatively returned to normal after surgery except that the T wave in lead aVL remained negative. Postoperatively, left ventricular ejection fraction measured by technetium-99m cardiac pool imaging was normal in all patients. Postoperative thallium-201 myocardial imaging, however, showed a perfusion defect with incomplete redistribution at the high-lateral or antero-lateral segment in all patients after a stress test. These data suggest that although myocardial ischaemic change decreases and global cardiac function improves after establishment of a dual coronary artery system, severe myocardial damage remains at the high-lateral or antero-lateral segment. 相似文献