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排序方式: 共有4251条查询结果,搜索用时 15 毫秒
101.
Amir Beker Jacob Erel Abraham Pinchas Shimon Abboud 《Annals of noninvasive electrocardiology》1996,1(4):386-392
Background: The effect of acute myocardial infarction and regional ischemia on the frequency content of the ECG signal has been described by several investigators. In the present study, the feasibility of assessing changes in the QRS spectrum during exercise testing, and whether these changes are related to the occurrence of ischemia were examined. Methods: Spectral analysis of the high resolution ECGs from leads V3, V4, V5, and V6 were performed in two groups of male subjects before, during, and following treadmill exercise testing. Group A included 32 coronary artery disease (CAD) patients, with arteriographically proven >75% obstruction of at least two main coronary arteries, and group B included 30 healthy subjects, without history or symptoms of CAD. Signal averaging and filtering techniques were used in order to enhance the signal-to-noise ratio of the recorded ECGs. The power spectrum of the averaged QRS waveform for the different stages of the exercise testing was computed using a Fast Fourier Transform, and the slope of the linear regression line was found in the frequency range 7.81–249.92 Hz on the plot of log((amplitude)2) versus log(frequency). Results: Regression line slopes immediately after peak exercise were significantly lower for the CAD group than for the healthy subjects in 3 of the 4 examined leads. No significant changes in slopes were found between the two groups at rest or during late recovery. Comparing the differences between slopes at different stages of the test revealed that the difference between postexercise slope and rest slope has lower mean values for the CAD group in all four leads, with a significant difference in lead V6, and for the difference between postexercise slope and recovery slope, lower mean values were found for the CAD group in all four leads, with a significant difference in V5 and V6. Conclusions: These findings indicate that ischemic changes affect the power spectrum of the QRS complex, and result in a steeper regression line on a log-log scale. 相似文献
102.
Kuriyama M Kato J Kuwaki K Morimoto N Nawa T Fujimoto T Kono H Okano N Miyaike J Morita T Okada H Suzuki S Yoshioka T Shiode J Suwaki K Sakaguchi K Shiratori Y;Japan West Ulcerative Colitis Study Group 《European journal of gastroenterology & hepatology》2008,20(7):634-641
BACKGROUND AND AIM: The health-related quality of life (HRQOL) of patients with ulcerative colitis (UC) can be impaired because of the chronic symptoms. Although UC patients suffer from such symptoms over the long term, there have been few reports on the changes of HRQOL with disease duration. The aim of this study was to clarify these changes. METHODS: The HRQOL of 331 Japanese UC patients was examined using the validated Japanese version of the Inflammatory Bowel Disease Questionnaire (J-IBDQ). HRQOL and factors affecting HRQOL identified using multiple linear regression analysis were stratified by disease duration. RESULTS: Of the 15 clinical factors examined, the clinical activity index score was the strongest determinant (P<0.0001) of all the scores of IBDQ regardless of disease duration. HRQOL did not differ significantly among patients with different disease durations. The factors, however, that affected HRQOL varied according to disease duration. In patients with disease duration of less than 5 years, the clinical activity index score was the predominant factor affecting HRQOL. Being 'on sick leave or hospitalized' was a significant factor impairing HRQOL in patients with disease duration of 5-9 years. Moreover, complications due to corticosteroids significantly impaired all of the IBDQ scores in patients with disease duration of 10 years or more. CONCLUSION: Factors that affected the HRQOL of UC patients varied according to the patients' disease duration. Our findings should assist in the development of a long-term strategy for the treatment of UC patients. 相似文献
103.
Takenaka R Kawahara Y Okada H Tsuzuki T Yagi S Kato J Ohara N Yoshino T Imagawa A Fujiki S Takata R Nakagawa M Mizuno M Inaba T Toyokawa T Sakaguchi K 《Gastrointestinal endoscopy》2008,67(2):359-363
BACKGROUND: Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE: Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN: Case series. SETTING AND PATIENTS: A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION: ESD. MAIN OUTCOME MEASUREMENTS: En bloc resection rate, complete resection rate, operation time, and complications. RESULTS: En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION: Short duration of follow-up. CONCLUSIONS: ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists. 相似文献
104.
Pulmonary ventricular outflow reconstruction with a size-reduced cryopreserved pulmonary valve allograft: mid-term follow-up 总被引:1,自引:0,他引:1
Yoshikawa Y Kitamura S Taniguchi S Kameda Y Niwaya K Sakaguchi H 《Japanese circulation journal》2000,64(1):23-26
Surgical reduction of pulmonary allografts is being performed because of the shortage of allografts of suitable size for pediatric use. However, the outcome of size-reduced pulmonary allografts for pulmonary conduits is unknown. In the present study, cryopreserved pulmonary allografts harvested from adults at the time of kidney donation were size-reduced and used in 4 children, 2 with pulmonary atresia and ventricular septal defect and 2 with atrioventricular discordance, pulmonary atresia and ventricular septal defect. They all had undergone right and/or left modified Blalock-Taussig shunt operations with a 5-mm synthetic graft prior to the reparative operations. They underwent definitive repair with a size-reduced cryopreserved pulmonary allograft valved conduit and were followed up for 2-5 years. Postoperative echocardiographic and cineangiographic assessments revealed excellent function of the pulmonary bicuspidalized valves with a minimal pressure gradient and no, or only trivial, regurgitation. Although the long-term result of a cryopreserved bicuspid pulmonary valved conduit remains unknown, the remodeled bicuspid pulmonary allograft conduits showed excellent hemodynamic characteristics in mid-term follow-up and appear to be a reasonable alternative to other types of conduits when an appropriate-sized allograft is not available. 相似文献
105.
Sakaguchi M 《Allergie et immunologie》2000,32(3):97-98
The natural occurrence of CJ pollinosis has been found in Japanese monkeys and dogs. These animals have reactivity to CJ major allergens. Monkeys and dogs can serve as a suitable animal model in the study of CJ pollinosis. 相似文献
106.
Daisuke Kozai Reiko Sakaguchi Tomohiko Ohwada Yasuo Mori 《Current Neuropharmacology》2015,13(2):266-278
The transient receptor potential (TRP) proteins are a family of ion channels that act as
cellular sensors. Several members of the TRP family are sensitive to oxidative stress mediators.
Among them, TRPA1 is remarkably susceptible to various oxidants, and is known to mediate
neuropathic pain and respiratory, vascular and gastrointestinal functions, making TRPA1 an
attractive therapeutic target. Recent studies have revealed a number of modulators (both activators and inhibitors) that act
on TRPA1. Endogenous mediators of oxidative stress and exogenous electrophiles activate TRPA1 through oxidative
modification of cysteine residues. Non-electrophilic compounds also activate TRPA1. Certain non-electrophilic
modulators may act on critical non-cysteine sites in TRPA1. However, a method to achieve selective modulation of
TRPA1 by small molecules has not yet been established. More recently, we found that a novel N-nitrosamine compound
activates TRPA1 by S-nitrosylation (the addition of a nitric oxide (NO) group to cysteine thiol), and does so with
significant selectivity over other NO-sensitive TRP channels. It is proposed that this subtype selectivity is conferred
through synergistic effects of electrophilic cysteine transnitrosylation and molecular recognition of the non-electrophilic
moiety on the N-nitrosamine. In this review, we describe the molecular pharmacology of these TRPA1 modulators and
discuss their modulatory mechanisms. 相似文献
107.
Production of cytokines by peripheral blood monocytes/macrophages infected with human immunodeficiency virus type 1 (HIV-1) 总被引:12,自引:0,他引:12
J M Molina R Schindler R Ferriani M Sakaguchi E Vannier C A Dinarello J E Groopman 《The Journal of infectious diseases》1990,161(5):888-893
The study of monocyte/macrophage functions after human immunodeficiency virus type 1 (HIV-1) infection may help in understanding the pathogenesis of AIDS. The production of four cytokines, tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and granulocyte-macrophage colony-stimulating factor (GM-CSF), by peripheral blood monocytes/macrophages was evaluated after in vitro infection with HIV-1. HIV-1 infection of these monocytes/macrophages did not result in release of any of these cytokines. Similarly, treatment of uninfected cells with purified recombinant HIV-1 envelope protein did not result in cytokine production. After stimulation with endotoxin or endotoxin plus interferon-gamma, HIV-1-infected monocytes/macrophages produced amounts of TNF alpha, IL-6, GM-CSF, and IL-1 beta comparable to that of uninfected cells. HIV-1 infection does not appear to induce or alter cytokine production by mononuclear phagocytes, which retain the capacity to produce these cytokines after endotoxin stimulation. 相似文献
108.
109.
Clinical features of Japanese type 1 autoimmune hepatitis patients with zone III necrosis 总被引:1,自引:0,他引:1
Yasuhiro Miyake Yoshiaki Iwasaki Ryo Terada Toru Onishi Ryoichi Okamoto Kouichi Takaguchi Hiroshi Ikeda Yasuhiro Makino Haruhiko Kobashi Kohsaku Sakaguchi Yasushi Shiratori 《Hepatology research》2007,37(10):801-805
Aim: In Caucasians in northern Europe and North America, type 1 autoimmune hepatitis is characterized by susceptibility to human leukocyte antigens DR3 and DR4, and patients with zone III necrosis more frequently have an acute onset of the disease and a lower frequency of cirrhosis than those without. In Japanese patients, however, type 1 autoimmune hepatitis is primarily associated with DR4, and there are almost no DR3-positive patients. Thus, the clinical features of Japanese patients with type 1 autoimmune hepatitis and zone III necrosis may be different from those reported previously for Caucasians. Methods: We investigated 160 consecutive patients with type 1 autoimmune hepatitis (20 males and 140 females; median age, 55 years; range, 16-79 years). Results: Forty-seven patients (29%) had zone III necrosis, and these patients had lower serum levels of albumin and higher serum levels of total bilirubin, aspartate aminotransferaseand alanine aminotransferase. Histologically, zone III necrosis was found more frequently in patients with acute hepatitis than in those with chronic hepatitis. However, there was no difference in the frequency of cirrhosis between patients with and without zone III necrosis. In addition, normalization of serum alanine aminotransferase levels within six months after the introduction of corticosteroid treatment was slightly more frequent in patients with zone III necrosis (95% vs. 88%). Conclusion: In Japanese patients, zone III necrosis may reflect not only acute autoimmune hepatitis, but also acute exacerbation of pre-existing chronic disease. Furthermore, patients with zone III necrosis may respond better to corticosteroid treatment than those without. 相似文献
110.
Yasushi Okuaki Hiroshi Miyazaki Mikio Zeniya Tomohisa Ishikawa Yasuhiko Ohkawa Shinichi Tsuno Masami Sakaguchi Masaki Hara Hiroki Takahashi Gotaro Toda 《Liver international》1996,16(3):188-194
Abstract: In the present study, we investigated the role of the spleen in experimental hepatic ischemia/reperfusion in the rat. After a 90-min period of ischemia in the left and middle hepatic lobes, the ischemia was released and the liver was reperfused for up to 24 h. Plasma alanine aminotransferase reached a peak 3 h after the onset of reperfusion, and gradually decreased thereafter. A histological examination revealed evidence of hepatocellular necrosis and degeneration, especially 24 h after the onset of reperfusion. In addition, there was a noticeable accumulation of polymorphonuclear cells in the liver following ischemia/reperfusion. A splenectomy performed just prior to ischemia/reperfusion reduced both biochemical and histological hepatocellular injury. The number of polymorphonuclear cells in the liver following ischemia/reperfusion was significantly reduced in rats subjected to splenectomy, suggesting that the increase in polymorphonuclear cells may contribute to liver injury. The number of mononuclear cells also increased in the marginal zones of the spleen following ischemia/reperfusion, and appeared to be derived from the splenic monocyte/macrophage population, based on immunohistochemical studies. The spleen plays an important role in the pathogenesis of hepatic ischemia/reperfusion injury and the splenic monocyte/macrophage population contributes to liver damage. 相似文献