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991.
Use of echocardiography for predicting myocardial viability in patients with reperfused anterior wall myocardial infarction 总被引:1,自引:0,他引:1
Iwakura K Ito H Nishikawa N Sugimoto K Shintani Y Yamamoto K Higashino Y Masuyama T Hori M Fujii K 《The American journal of cardiology》2000,85(6):744-748
Dobutamine stress echocardiography (DSE), myocardial contrast echocardiography (MCE), and ultrasonic tissue characterization with integrated backscatter are useful methods for assessing myocardial viability in acute myocardial infarction. In this study, we compared the potential of 3 methods for predicting myocardial viability in 38 patients with reperfused anterior wall acute myocardial infarction. We performed MCE shortly after coronary reperfusion with an intracoronary injection of microbubbles. We recorded 2-dimensional integrated backscatter images at rest and, then, performed low-dose (10 microg/kg/min) DSE 3 days later. In integrated backscatter images, we placed the region of interest in the midwall of the myocardial segment to reconstruct the cyclic variation of myocardial integrated backscatter. The myocardial segment was judged viable when it showed active contraction 3 months later. Among 74 segments analyzed, 34 were judged viable. Presence of contractile response during DSE predicted segmental viability with 91% sensitivity and 78% specificity. Intense and homogenous contrast enhancement with MCE predicted viability with 82% sensitivity and 73% specificity. The presence of synchronous contraction of cyclic variation predicted myocardial viability with 79% sensitivity and 83% specificity. There were no differences in sensitivity and specificity among the 3 methods. Thus, MCE and ultrasonic tissue characterization can predict myocardial viability as accurately as DSE in patients with acute myocardial infarction. The logistics of the methods may determine clinical application. 相似文献
992.
Kenji Yonekura Takafumi Ichida Kazunari Sato Satoshi Yamagiwa Moriaki Uchida Satoshi Sugahara Shinichi Ito Toru Abo Hitoshi Asakura 《Liver international》2000,20(5):357-365
Abstract: Aim: Hepatitis C virus (HCV) is a major cause of post‐transfusional and sporadic hepatitis, and leads to chronic liver disease. It has been suggested that virus‐specific cytotoxic T lymphocytes are responsible for liver injuries that occur in HCV‐infected patients. However, the detailed characteristics of these lymphocytes have not yet been defined. We have previously reported that CD56+ T lymphocytes, as intermediates between natural killer cell and T lymphocytes, predominantly infiltrated the liver and were increased in patients with chronic hepatitis related to HCV (CH‐C). Material and Methods: We obtained peripheral blood and liver tissues from 32 patients diagnosed as having CH‐C, and 10 other liver disease patients (5 chronic hepatitis related to HBV, 5 alcoholics), and analyzed peripheral blood and liver‐infiltrating lymphocytes using flow cytometric and immunohistochemical techniques. Results: The CD56+ T lymphocyte ratio in the liver of patients with a high histology activity index (HAI) score for chronic hepatitis was higher than that of patients with a low HAI score and patients with other liver diseases. In addition, T lymphocytes from patients with chronic hepatitis with a high HAI score carried mostly γδ‐TCR. There was a correlation between the ratio of CH‐C and serum alanine aminotransferase, category I (periportal inflammation and necrosis), and IV (fibrosis) of the HAI scoring system. The ratio was highest in zone 1 of the hepatic lobules. Conclusion: The correlation between CD56+ T lymphocyte ratios and hepatocellular damage was examined. These findings suggest strongly that liver‐infiltrating CD56+ T lymphocytes play an important pathologic role in hepatocellular injury in CH‐C. 相似文献
993.
994.
Effects of betazole hydrochloride and cyclic AMP on the pepsinogen secretion by rabbit gastric mucosa in organ culture 总被引:1,自引:0,他引:1
M Ito Y Noguchi K Yokochi T Kishimoto T Tomomatsu K Katsumi T Takeuchi 《Digestion》1982,23(3):169-173
The effects of betazole hydrochloride, dibutyryl cyclic AMP (DB-cyclic AMP) and betazole hydrochloride plus aminophylline on pepsinogen secretion by rabbit gastric mucosa were studied in organ culture. Betazole hydrochloride alone did not stimulate pepsinogen secretion at the concentrations of 10(-8), 10(-6), 10(-5) and 10(-4) M. However, 10(-3) M DB-cyclic AMP produced a significant stimulation of pepsinogen secretion into the culture medium when compared with the control. In the presence of 3 x 10(-3) M aminophylline, betazole hydrochloride in the concentration of 10(-5) and 10(-4) M stimulated pepsinogen secretion into the culture medium, and the magnitude of this increase was 2.0- and 2.8-fold, respectively, compared with the control. Aminophylline alone could not change pepsinogen secretion into the culture medium. These results suggested that the pepsinogen secretion, stimulated by betazole hydrochloride, was mediated by cyclic AMP in the chief cells. 相似文献
995.
OBJECTIVE: To elucidate the mechanism of the reported association between serum gamma-glutamyl transferase (GGT) activity and cardiovascular mortality. METHODS: Cross-sectional analysis of the relationship between serum GGT activity and the risk factors for cardiovascular disease was performed. PATIENTS AND MATERIALS: Middle-aged Japanese male personnel of the Self-Defense Forces who underwent retirement check-up. RESULTS: Serum GGT activity was associated with total cholesterol, triglyceride, fasting plasma glucose, total homocysteine and systolic blood pressure. The association remained in the analysis adjusted for possible confounders including cigarette smoking, ethanol consumption and body mass index. CONCLUSION: The observed association between serum GGT and cardiovascular risk factors may partly explain the reported relationship between serum GGT activity and cardiovascular disease. Serum GGT activity may be regarded as a marker of cardiovascular risk factors or oxidative stress rather than a mere indicator of excessive ethanol consumption or obesity. 相似文献
996.
Ito H Osteen RT Bleday R Zinner MJ Ashley SW Whang EE 《Diseases of the colon and rectum》2004,47(4):474-480
PURPOSE Appendiceal adenocarcinomas are very rare. We analyzed contemporary outcomes associated with surgical therapies for these malignancies.METHODS Retrospective outcomes for patients treated at a tertiary academic medical center from 1981 through 2001 were analyzed.RESULTS A total of 36 patients (22 females (61 percent) mean age, 52 years) with appendiceal adenocarcinoma were treated. Eighty-eight percent of patients presented with symptoms of acute appendicitis. Eighteen (50 percent) patients underwent curative resection (7 primary right hemicolectomies, 10 appendectomies + subsequent right hemicolectomy, and 1 appendectomy alone). Mean length of follow-up was 55 months. Overall five-year survival rate was 46 percent. The five-year survival rate after curative resection was 61 percent and after palliative surgery was 32 percent (P < 0.05). Among patients who underwent curative resection, factors associated with improved five-year survival rates included histologic type (79 vs. 32 percent for colonic vs. mucinous types, respectively; P < 0.05), T stage (75 vs. 47 percent for T1 and 2 vs. T3 and 4, respectively; P < 0.05), and tumor grade (100 vs. 46 percent for well-differentiated tumors vs. moderately or poorly differentiated tumors, respectively; P < 0.05).CONCLUSIONS Patients undergoing surgery for appendiceal adenocarcinoma can be stratified according to prognostic variables. The role of adjuvant therapies for patients with poor prognostic factors needs to be evaluated in a multi-institutional setting.Presented at World Congress of Digestive Surgery, Hong Kong, China, December 9 to 11, 2002. 相似文献
997.
998.
Yamada H Oki T Tabata T Mishiro Y Abe M Onose Y Wakatsuki T Iuchi A Ito S 《Echocardiography (Mount Kisco, N.Y.)》1999,16(8):775-783
To determine the systolic characteristics of the hypertrophied myocardium in patients with hypertrophic cardiomyopathy (HCM), we evaluated the left ventricular [left ventricle (LV)] myocardial velocity profile (MVP) and gradient obtained from tissue Doppler imaging (TDI). Transmural wall-motion velocities in the ventricular septum and LV posterior wall were recorded in 12 patients with asymmetric septal hypertrophy and 12 healthy volunteers, and their profiles and gradients were determined. The maximum systolic myocardial velocity gradient in the ventricular septum was significantly lower in the HCM group than in the control group (0.88 ± 0.35 versus 2.24 ± 0.41; P < 0.001), whereas the gradient in the LV posterior wall was only slightly lower in the HCM group than in the control group (2.69 ± 0.82 versus 3.45 ± 0.96). In the control group, the MVPs in the ventricular septum and LV posterior wall were closely linear, suggesting that the transmural velocity is uniform during systole. MVPs in the ventricular septum and LV posterior wall in the HCM group also were closely linear, whereas the distribution of velocities in the ventricular septum was fairly dispersed compared with the control group. The myocardial velocity gradient on the right ventricular side of the ventricular septum decreased or disappeared in the patients with HCM, suggesting a nonuniform distribution of velocities. In conclusion, the MVP and gradient obtained from TDI may represent new indices for evaluating regional LV contractile abnormality in patients with HCM. 相似文献
999.
1000.
Miyaji H Azuma T Ito S Abe Y Gejyo F Hashimoto N Sugimoto H Suto H Ito Y Yamazaki Y Kohli Y Kuriyama M 《Journal of gastroenterology and hepatology》2000,15(3):257-262
BACKGROUND: The manner in which Helicobacter pylori is transmitted is of fundamental importance when considering strategies for its control, yet, to date, the exact mode of transmission remains uncertain. METHODS: The seroprevalence of H. pylori in a relatively isolated rural town in Japan (A-town) was examined to analyse the H. pylori infection route. The immunoglobulin G antibodies against H. pylori in 1684 subjects who had received public health examinations in A-town were determined with an enzyme-linked immunosorbent assay. The seroprevalence was compared in five areas according to the water source. The possibility and frequency of intrafamilial infection was analysed by comparing the seroprevalence among family members residing in the same home. RESULTS: The seroprevalence of H. pylori did not differ significantly between the five areas examined. Seropositivity was significantly more common in the children whose mothers were seropositive (45.0%, 27/60) than in the children whose mothers were seronegative (10.0%, 2/20; odds ratio (OR) = 7.36, P = 0.0036, 95% confidence interval (CI) = 1.57-34.59). Seropositivity was significantly more common in the children whose older siblings were seropositive (55.0%, 22/40) than in the children whose older siblings were seronegative (23.5%, 20/85; OR = 3.97, P = 0.00051, 95% CI = 1.79-8.84). There was no significant relationship in seroprevalence between children and fathers, grandchildren and grandfathers, grandchildren and grandmothers, or within couples. Seropositivity was significantly more common in the adolescents who had attended a nursery school (44.4%, 20/45) than in the adolescents who had not attended a nursery school (25.6%, 109/426) (OR = 2.33, P = 0.0070, 95% CI = 1.24-4.36). CONCLUSIONS: The acquisition of H. pylori infection occurs by close contact with infected individuals in early childhood, especially via contact with infected mothers and other infected children. 相似文献