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901.
This report describes a patient with a single coronary artery in whom the right coronary artery originated from the distal left circumflex artery. Single coronary artery is a rare congenital anomaly of the coronary circulation which is often associated with other congenital cardiac malformations. This anomaly is thought to be clinically significant especially in patients with atrial fibrillation, although no other associated cardiac anomaly was detected.  相似文献   
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BACKGROUND/AIMS: We investigated the impact of different treatments on the prognosis of cirrhosis patients with esophageal varices and thrombocytopenia. METHODOLOGY: This prospective study enrolled 52 cirrhosis patients with esophageal varices and hypersplenism (platelet count < 50,000/mm3). In 26 patients, endoscopic variceal ligation plus partial splenic embolization were performed, while endoscopic variceal ligation alone was done in 26 patients. Endoscopic variceal ligation was repeated until complete eradication of varices was achieved. Partial splenic embolization was performed using the Seldinger method and embolic material was injected until a 60% to 80% reduction of splenic blood flow was achieved. The primary endpoints during the follow-up period included recurrence of varices, variceal bleeding, and death. RESULTS: Comparison of endoscopic variceal ligation plus partial splenic embolization with endoscopic variceal ligation alone by multivariate analysis showed a relative risk ratio of 0.390 (95% CI [0.178-0.854]; p = 0.024) for new varices, 0.191 (95% CI [0.047-0.780]; p = 0.021) for variceal bleeding, and 0.193 (95% CI [0.053-0.699]; p = 0.012) for death. CONCLUSIONS: These results suggest that endoscopic variceal ligation plus partial splenic embolization can prevent variceal recurrence, bleeding, and death in cirrhosis patients with esophageal varices and thrombocytopenia.  相似文献   
904.
Carnosine, homocarnosine, and anserine are present in high concentrations in the muscle and brain of many animals and humans. However, their exact function is not clear. The antioxidant activity of these compounds has been examined by testing their peroxyl radical-trapping ability at physiological concentrations. Carnosine, homocarnosine, anserine, and other histidine derivatives all showed antioxidant activity. All of these compounds showing peroxyl radical-trapping activity were also electrochemically active as reducing agents in cyclic voltammetric measurements. Furthermore, carnosine inhibited the oxidative hydroxylation of deoxyguanosine induced by ascorbic acid and copper ions. Other roles of carnosine, such as chelation of metal ions, quenching of singlet oxygen, and binding of hydroperoxides, are also discussed. The data suggest a role for these histidine-related compounds as endogenous antioxidants in brain and muscle.  相似文献   
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OBJECTIVE: To compare the efficacy and safety of two antiplatelet regimens, ticlopidine alone (200 mg daily) and ticlopidine (100 mg daily) plus aspirin (81 mg daily), in patients with ischemic stroke from the Tokai district of Japan. METHODS: A randomized comparative study was performed from April 1992 until December 1995, with follow-up for an average of 1.59 years (maximum: 3 years). Statistical analysis was done on 270 eligible patients (138 treated with ticlopidine alone and 132 treated with ticlopidine plus aspirin). PATIENTS: A total of 276 patients who had cerebral infarction within the previous 1 to 6 months, or one or more transient ischemic attacks within the previous 3 months. RESULTS: The incidence of ischemic and hemorrhagic stroke, myocardial infarction, and other vascular events was 10.1% (n = 14) in the ticlopidine group and 9.8% (n = 13) in the ticlopidine plus aspirin group, showing no significant difference (p = 0.933). There was also no significant difference in the event-free rate between the two groups (p = 0.5003, Kaplan-Meier analysis and log-rank test). Regarding serious adverse reactions, neutropenia occurred in one patient from the ticlopidine group, while gastric ulcer and thrombocytopenia occurred in one patient each from the ticlopidine plus aspirin group. CONCLUSION: We conclude that both antiplatelet regimens are comparable in efficacy and safety for preventing the recurrence of ischemic stroke.  相似文献   
909.
910.
OBJECTIVE: Although isolated diastolic heart failure with preserved left ventricular (LV) systolic function frequently occurs, regulation of local neurohumoral factors in the transition from diastolic dysfunction without signs of heart failure to diastolic failure, a target for therapeutic strategy, remains to be clarified, partly because of a lack of animal models. Our laboratory recently demonstrated that Dahl-Iwai salt-sensitive (Dahl-S) rats fed on a high-salt diet since 7 weeks of age develop hypertension followed by compensated LV hypertrophy at 13 weeks and transition to isolated diastolic heart failure at 19 weeks. METHODS: Gene expression of the components of the renin-angiotensin system, endothelin (ET) system and natriuretic peptide system in the left ventricle was investigated in the transition to isolated diastolic heart failure in this model. RESULTS: The compensated ventricular hypertrophy was associated with slight increases in angiotensin-converting enzyme (ACE) and angiotensin II type-1a (AT1a) receptor mRNA levels. Although preproET-1 (ppET-1) and ET-converting enzyme-1 (ECE-1) mRNA levels were not increased, mRNA levels of ET type-A (ETA) and ET type-B (ETB) receptors were increased. Atrial natriuretic peptide (ANP) mRNA level increased, but not brain natriuretic peptide (BNP) mRNA level. At the decompensated failing stage (at 19 weeks), ACE mRNA level further increased without downregulation of ATla receptor mRNA level. The mRNA levels of ppET-1 and ECE-1 increased with persistent upregulation of mRNA levels of ETA and ETB receptors, and immunohistochemical staining for ET-1 was found at endothelial cells and myocytes. BNP mRNA level increased with a further increase in ANP mRNA level. CONCLUSIONS: The transition to isolated diastolic heart failure in hypertrophied hearts was associated with preserved gene expression of the renin-angiotensin system and 'overdrive' of gene expression of the ET system. BNP gene expression is likely to be activated by the progression of diastolic failure rather than by LV hypertrophy alone.  相似文献   
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