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991.
We report a case of macroscopic T-wave alternans occurring 30 min before the onset of amiodarone-induced torsade de pointes, illustrating a means to monitor for proarrhythmia.  相似文献   
992.
993.
Catechins, compounds derived from green tea, have been shown to improve cholesterol metabolism in animal studies, but the molecular mechanisms underlying this function have not been fully understood. We performed DNA microarray analysis in order to clarify the effects of epigallocatechin gallate (EGCG), the dominant catechin in green tea, on cholesterol metabolism in HepG2 hepatocytes. This revealed that the expression levels of several genes related to cholesterol metabolism, including the LDL receptor, were changed by EGCG treatment. Using a real-time PCR technique, we confirmed that EGCG treatment up-regulated mRNA expression level of the LDL receptor. Moreover, EGCG decreased extracellular apoB levels. These findings indicated that EGCG improves cholesterol metabolism through the up-regulation of LDL receptor and also reduces extracellular apoB levels.  相似文献   
994.
995.
A 78‐year‐old man with a history of open sigmoidectomy for sigmoid cancer presented with abdominal pain and vomiting. Abdominal multi‐detector CT revealed an obstructive ileocecal tumor with distended small bowel on the oral side. We performed emergency drainage using a transnasal decompression tube, and 2 days later, we conducted a colonoscopic examination, which lead to a provisional diagnosis of obstruction with a malignant tumor invading the ileocecal valve. We then placed a self‐expanding metallic stent (SEMS) through the ileocecal valve. We confirmed patency of the ileocecal valve and removed the transnasal decompression tube 2 days after SEMS placement. We then performed elective laparoscopic colectomy 8 days after SEMS placement. To the best of our knowledge, there has been only one previous report of laparoscopic colectomy after decompression with SEMS placement through the ileocecal valve for right‐sided malignant colonic obstruction.  相似文献   
996.
Minimal access via lower partial sternotomy for congenital heart defects   总被引:2,自引:0,他引:2  
To evaluate the invasiveness of a minimal access approach for simple congenital heart defects, and determine whether it can be regarded as a standard operation, 83 patients with an atrial septal defect and 73 with a ventricular septal defect underwent repair through a minimal skin incision and lower partial median sternotomy. There were no operative deaths, severe intraoperative complications, or conversion to full sternotomy. The clinical course of 106 patients was compared with that of 21 treated using a full sternotomy by the same surgeon; there were no significant differences, except in the operative time for ASD patients. The clinical courses of 2 minimal access subgroups (50 patients operated on by residents and 106 treated by the staff surgeon were compared; operative time, bypass time, ventricular fibrillation time (ASD repair), and cardiac arrest time (VSD repair) were significantly shorter in those operated on by the staff surgeon, but there was no difference in clinical course. The minimal access approach produced good cosmetic results, its invasiveness was similar to that of a full sternotomy, and it may be considered a standard operation for pediatric patients with septal defects.  相似文献   
997.
OBJECTIVES: This study focused on 1) the determination of the optimal preconditioning (PC) duration, and 2) the protective effect of nicorandil (NC), a hybrid nitrate with a KATP channel opening effect, during a percutaneous transluminal coronary angioplasty (PTCA) model in humans. BACKGROUND: The ischemic PC effect is induced in 180 s ischemia, but not in 120 s ischemia in rabbit hearts. However, the duration of ischemia that induces PC effect and the role of the KATP channel in the PC effect in humans are still unclear. METHODS: Forty-six patients with stable angina were randomly allocated to four groups: the duration of the first inflation as PC ischemia was 60 s in the PC60 group (n = 12), and 180 s in the PC180 group (n = 12). In the other groups, NC (80 microg/kg) was intravenously given for 1 min in the NC group (n = 12), and isosorbide dinitrate (ISDN) (40 microg/kg) was given in the ISDN group (n = 10). Five minutes after first inflation or drug administration, a second inflation was conducted for 120 s in each group. In the ECG, the lead with the largest shift in ST segment (deltaST max), and the sum of elevated ST levels in all leads (sigmaST) were determined. RESULTS: In the PC60 group, no significant difference was observed in either deltaST max or sigmaST between the first and second inflation. However, the second inflation in the PC180 group showed significantly lower levels of deltaST max and sigmaST compared with those of the first inflation. In the NC group, both deltaST max and sigmaST measured at 30 s and 60 s after balloon inflation were significantly lower than those of the first inflation in the PC60 and PC180 control groups. In the ISDN group, no significant difference was observed in deltaST max or sigmaST. CONCLUSION: In human PTCA models, a PC effect is observed in 180 s ischemia, but not in 60 s ischemia. A pharmacological PC effect is induced by NC, a KATP channel opener with a nitrate-like effect but not ISDN. This suggests that the opening of KATP channels plays an important role in the protecting effect of NC.  相似文献   
998.
Gastric inflammatory fibroid polyps (IFPs) are rare benign lesions that occur in the distal stomach. We describe a 70-year-old woman with Helicobacter pylon-positive gastric IFP treated with eradication. Gastroduodenal endoscopy revealed a pyramidal-shaped, broad-based tumor with an ulcerated apex at the antrum. Helicobacter pylori was positive by both histology and tissue culture, and eradication (a proton pump inhibitor, amoxicillin, and clarithromycin) was performed. After 3 months, the tumor morphologically changed and the apex ulcer was markedly enlarged. This case suggests that H. pylori may play a role in the pathophysiology of IFPs.  相似文献   
999.
We report on two patients diagnosed as having Mycobacterium xenopi infections. Case 1 occurred in a 40-year-old man. His chest radiograph revealed a cavitary lesion with a granular shadow in the right upper lung field. His sputum and bronchial lavage were negative for acid-fast bacilli and malignant cells. For a definitive diagnosis, lung resection was performed by video-assisted thoracoscopy. Case 2 was in a 45-year-old man. His chest radiograph showed a cavitary lesion with infiltration in the right upper lung field. Acid-fast bacilli were seen in his sputum specimens and M. xenopi was identified by culture. Despite medication with isoniazide, rifampicin and ethambutol, the infiltrative shadow in his radiograph increased in size. In this case, right upper lobectomy was performed. In recent years, 8 cases of pulmonary Mycobacterium xenopi infection have been reported in Japan. In the future, the number of such case reports may increase as a result of diagnosis by molecular biological methods. It is necessary to consider carefully whether surgical resection is required when chemotherapy is refused by the patient or is likely to be unsuccessful.  相似文献   
1000.
INTRODUCTION: The aim of this study was to clarify the ventricular tachyarrhythmia mechanism induced by the I(Kr)-blocking agent E4031, simulating the LQT2 form. Electrophysiologic properties were examined in 13 canines before and after administration of E4031. METHOD AND RESULTS: Thirty-six needle electrodes were inserted into the anterior left ventricular wall. From each needle, local unipolar electrograms were obtained from four intramural sites. Activation time (AT) and activation-recovery interval (ARI) were measured. To evaluate the susceptibility to ventricular arrhythmia, intramural ARI dispersions and the restitution relationship between ARI and diastolic interval were calculated. After E4031 administration, ARI prolonged uniformly in each myocardial layer. However, ARI dispersion was not augmented compared with control. The slope of the ARI restitution curve after E4031 was significantly steeper than control. A steep slope may result from augmented ARI alternans. In 11 of the 13 canines, ventricular tachyarrhythmia was induced by programmed stimulation after E4031, whereas no arrhythmia was induced by the same protocol in control. CONCLUSION: Steepness of electrical restitution may play a major role in arrhythmogenicity in LQT2 hearts.  相似文献   
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