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81.
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83.
In two patients, ventricular pamsystole (VP) was associated with ventricular tachycardia (VT), and in one patient, catheter ablation was successful. In patient 1, with dilated cardiomyopathy, VP led to VT, which converted to ventricular fibrillation. In patient 2, VP led to symptomatic nonsustained polymorphic VT. The origin of parasystolic focus was determined byendocardial mapping, and a radiofrequency current was delivered to patient 2. Both VP and VT disappeared immediately, and no recurrence has been observed during a follow-up of 8 months. Catheter ablation to the parasystolic focus was effective and a relationship between VP and VT was strongly suggested.  相似文献   
84.
OBJECTIVES: In a variety of cancers, several polymorphisms of the tumor necrosis factor (TNF) genes have been reported to result in different clinical outcomes. We investigated whether a polymorphism of the TNF gene is associated with a susceptibility to bladder cancer and its disease status. METHODS: Polymorphisms in the TNF-alpha gene promoter (-308 bp) and the NcoI site in the first intron of the TNF-beta gene were analyzed in 141 Japanese patients with bladder cancer and 173 Japanese controls by polymerase chain reaction-restriction fragment length polymorphism. The correlations between the polymorphisms of the TNF genes and the clinicopathological features were analyzed. RESULTS: The number of cases and controls with TNF-alpha2 was too small to be assessable. In contrast, the TNF-beta1/2 genotype at the NcoI site in the first intron conferred a 1.71-fold increased risk of bladder cancer compared to the TNF-beta2/2 genotype. In the bladder cancer group, patients with the TNF-beta1 allele had a significantly higher risk for a high-grade tumor (grade 3) or carcinoma in situ (CIS) than those without the TNF-beta1 allele. Moreover, in the superficial bladder cancers, patients with the TNF-beta1 allele showed a significantly higher intravesical recurrence rate than those without the TNF-beta1 allele. CONCLUSION: This polymorphism in the TNF-beta gene appears to be associated with tumor occurrence and disease status, such as the tumor grade and the presence of CIS. Further study with an increased sample size is warranted.  相似文献   
85.
Transcatheter aortic valve implantation (TAVI) is an alternative treatment to surgical aortic valve replacement for treating severe aortic stenosis. With the increased use of TAVI, the risk of cerebrovascular complications during the procedure has become an emerging problem. We evaluated the safety and feasibility of our total cerebral protection methods using embolic protection devices (EPDs) for carotid artery stenting. We collected the results of cases in which the clinical team determined that our protection method was necessary among patients undergoing TAVI from May to October 2019 in our medical center. We applied this method to patients who had a potentially high risk of cerebrovascular events during the procedure. The methods of protection were selected comprehensively based on the potential of collateralization of brain perfusion when some arteries were blocked with a balloon, accessibility of the brain arteries, and the ability to cover the brain arteries with devices. Five patients, aged 83.8 ± 1.8 years, were included in the study. Technical success was achieved in all five patients. No cases showed any new neurological symptoms after the procedures; however, head MRI on the day after showed new ischemic lesions in three of five cases (60%). In all cases, emboli were found in the collected filters. This report demonstrates protection of the entire perfusion area in each case using EPDs in patients at high risk of intraoperative embolism. The methods we used were feasible and can potentially reduce cerebrovascular events following TAVI.  相似文献   
86.
We studied contrast-enhanced ultrasound (CEU) for recurrence of renal cell carcinoma (RCC) at the contralateral kidney during postoperative follow up of localized renal cell carcinoma. CEU successfully detected all recurring cases, despite the fact that 5/6 cases were observed using conventional ultrasound; the remaining one case was not detected using conventional ultrasound. CEU using Levovisto successfully revealed renal tumors as RCC. Lesions were diagnosed as cystic renal tumors by Bosniac classification, and pathological findings demonstrated RCC, in accordance with the prior tumor.  相似文献   
87.
In 44 patients with acromegaly treated by transsphenoidal pituitary microsurgery, the relationship between changes in pre- and post-operative GH dynamics and postoperative fasting plasma GH levels was examined to clarify which is the optimal approach for evaluating postoperative removal of the tumour. TRH, LHRH and bromocriptine tests, which act directly on the pituitary somatotroph, and the oral glucose tolerance test (oGTT) and insulin tolerance test (ITT), which act via hypothalamus, were carried out pre- and post-operatively. Abnormal responses postoperatively were found in most patients with fasting postoperative plasma GH over 5 ng/ml. In 24 patients with postoperative fasting plasma GH level of 5 ng/ml or below, 7 of 17 (41%) showed abnormal responses in the TRH test, 2 of 5 (40%) in the LHRH test and 3 of 13 (23%) patients in the bromocriptine test. All patients with a fasting plasma GH level less than 10 ng/ml, except for those with panhypopituitarism, showed normal responses to ITT and the paradoxical increases with the oGTT were absent. These results indicate that abnormal responses caused by a direct action on adenoma cells do not necessarily disappear even when the fasting plasma GH level is below 5 ng/ml. Abnormal responses caused by indirect actions, through the hypothalamus, disappear when the level is less than 10 ng/ml.  相似文献   
88.
Abstract— We investigated the metabolism of tolbutamide by using synthetic 1-butyl-3-(p-formylphenyl)sulphonylurea (ATB), an intermediate in the metabolic pathway of tolbutamide. ATB (40 mg kg?1) administered intravenously to rabbits was oxidized to 1-butyl-3-(p-carboxyphenyl)sulphonylurea (CTB) and also reduced to 1-butyl-3-(p-hydroxymethylphenyl)sulphonylurea (HMTB). Therefore, it is likely that in the metabolism of tolbutamide, the oxidation of HMTB to ATB involved the reverse reaction, suggesting the reduction of ATB to HMTB. The oxidation of ATB to CTB was inhibited by disulfiram pretreatment. ATB was detected in the blood following intravenous administration of HMTB in rabbits pretreated with disulfiram. These results, confirm that ATB is an intermediate in the oxidative metabolism of tolbutamide in the rabbit.  相似文献   
89.
Background: Local anesthetics have been demonstrated to attenuate acetylcholine-induced relaxation of vascular smooth muscle, but the mechanism responsible has not been elucidated. The present study was undertaken to ascertain whether this effect of local anesthetics is due to suppression of the vascular nitric oxide (NO)-cyclic GMP (cGMP) system. Methods: Isolated rat aortae were cut into helical strips and mounted in bathing solution to measure isometric tension changes. They were precontracted with phenylephrine (0.3 μM)then exposed to cumulative concentrations of relaxants including acetylcholine, sodium nitroprusside (SNP) and papaverine, in the absence or presence of local anesthetics. Aortaefor cGMP measurements were cut longitudinally into pairs of strips and bathed in the solution without tension. In the absence or presence of anesthetics, they were stimulated with acetylcholine or SNP, and the cGMP content of each strip was radioimmunoassayed. Results: Acetylcholine-induced, endothelium-dependent relaxation of phenylephrine-precontracted aortae was attenuated by lidocaine (30–300 μM), tetracaine (10–30 μM), bupivacaine (10–100 μM) and ropivacaine (30–100 μM). SNP-inducedrelaxation was attenuated by lidocaine (300 μM), tetracaine (30 μM), bupivacaine (10–100 μM) and ropivacaine (30–100 μM). Papaver-ine-induced relaxation was attenuated by lidocaine (300 μM), bupivacaine (30–100 μM) and ropivacaine(30–100 μM), and augmented by tetracaine (30 μM). Cyclic GMP levels in acetylcho-line-stimulated aortae were reduced significantly by lidocaine (300 μM), tetracaine(100 μM) and bupivacaine (300 μM) treatment, but not by ropivacaine (300 μM). SNP-stimulated cGMP levels were reduced by tetracaine (100 μM) but not by any other anesthetics at the concentrations tested. Conclusion: We conclude that lidocaine, tetracaine and bupivacaine suppress acetylcholme-stimulated formation of cGMP. However, the attenuation of acetylcholine-induced relaxation by local anesthetics is not totally ascribable to reduced cGMP levels.  相似文献   
90.
Abstract We treated a patient who had previously undergone a hepatic resection for ruptured hepatocellular carcinoma (HCC) but developed a solitary peritoneal recurrence at the site of the incision 8 years and 9 months later. Since no other recurrence was evident, we resected the tumour. The primary tumour was 2.5 cm in size and histological examination revealed HCC without any histological risk factors for intrahepatic recurrence. The peritoneal tumour consisted of less differentiated cancer cells than those found in the primary tumour. The positive rates of Ki-67 were 10% in the primary tumour and 23.3% in the peritoneal recurrence. The DNA indexes in both tumours were considered to be identical.
The comparison between the primary and peritoneal tumours suggested that the histological differentiation and proliferation activity can change after recurrence, in spite of consistent DNA ploidy contents. Clinically, a patient who undergoes a hepatic resection for ruptured HCC can survive for a long time, such as 10 years, if they have good liver function and small HCC without any histological risk factors for intrahepatic recurrence. However, since late recurrence is possible, a follow up for as long as 10 years is recommended.  相似文献   
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