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991.
A 62-year-old Japanese man was referred to our hospital because of general fatigue. Abdominal ultrasonography and enhanced computed tomography scanning revealed many enlarged lymph nodes, mainly around the pancreas tail and the hilus of the spleen. Neither blood examination nor gallium scintigraphy revealed any abnormalities, whereas the diagnostic tuberculin test was strongly positive. Because we could not reach a final diagnosis, an exploratory laparotomy was performed. Histopathological examination revealed mantle-cell lymphoma. After chemotherapy combined with radiotherapy, the lymph-node swelling had disappeared. Herein, we report this case of stage-I mantle cell lymphoma that was difficult to differentiate from metastatic pancreatic cancer and abdominal tuberculous lymphadenitis. Received: January 9, 2001 / Accepted: July 6, 2001 Reprint requests to: H. Yoshiji  相似文献   
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Since myocardial lesion size during radio-frequency (RF) ablation is limited at high power by impedance rise when electrode tip temperature exceed 100 °C, controlling tip temperature by continuous intraelectrode saline infusion could permit generation of larger lesion. (1) Two dogs randomly received either standard or cooled tip RF ablation at 4 to 6 separate LV sites. Power output of 30 W was delivered via modified 7 Fr deflectable catheter with 4 mm tip for up to 120 sec or until impedance rise occurred. (2) Six dogs randomly received cooled tip RF ablation at power output of 20, 30, 40 W for 120 sec. (3) Three dogs randomly received cooled tip RF ablation using room temperature saline (21–25 °C) or chilled saline (1–4 °C) infusion. Results: Overall, peak tip temperature was lower for cooled vs standard RF deliveries (97±17 °C vs. 42±8 °C). Lesion depth and volume were significantly larger for cooled burns. Lesion depth and volume and the incidence of abrupt impedance rise/popping did not differ between room temperature saline and chilled saline infusion. The catheter-tip temperature at the onset of popping and abrupt impedance rise was 54±5 °C(48–60 °C) and 59±10 °C(50–75 °C). Conclusion: Cooled tip RF current delivery at high power is associated with increased myocardial lesion size which may facilitate successful ablation of ventricular tachycardia associated with acquired structural heart disease. Catheter-tip temperature should be maintained below 45 °C to prevent popping and abrupt impedance rise during RF energy delivery.  相似文献   
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To compare the effects of class Ic and III antiarrhythmic agents on the termination and prevention of atrial fibrillation, the present study investigated the use-dependent electrophysiological effects of flecainide, nifekalant and d,l-sotalol on the human atrium. Flecainide significantly prolonged effective refractory period (ERP), intra-atrial conduction time (IACT) and monophasic action potential duration (MAPD), and its effects on ERP and IACT were use-dependent. Nifekalalant significantly prolonged ERP and MAPD, and these effects were reverse use-dependent; however, there was no significant change in IACT. d,l-Sotalol significantly prolonged MAPD and the effect was reverse use-dependent. It significantly prolonged ERP, but the effect was not reverse use-dependent. d,l-Sotalol increased IACT in a use-dependent manner. Thus, for atrial fibrillation, class Ic antiarrhythmic agents might be more effective in termination and class III antiarrhythmic agents might be more effective in prevention.  相似文献   
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Ingestion of alcohol acutely decreases vascular resistance and blood pressure (BP) with activation of the sympathetic nervous system in Orientals. Although alpha1-blockers are widely used in the treatment of hypertension, the possible interaction between alcohol and alpha1-blockers has not been clarified. We examined the effects of prazosin on the alcohol-induced BP changes in Japanese men with mild hypertension. Ten hypertensive patients (54 +/- 3 years, mean +/- SE) were given 1 mL/kg of alcohol or isocaloric control drink with a light meal in the evening before and 5 to 7 days after treatment with prazosin (1 mg three times daily). Ambulatory BP monitoring was carried out every 30 min for 24 h in each period using Colin ABPM-630. Blood samples were obtained before and 2 h after intake of alcohol or control drink. Before prazosin treatment, alcohol ingestion decreased BP for several hours with a significant reduction in average 24-h BP, whereas it increased heart rate, plasma norepinephrine, and plasma renin activity. Treatment with prazosin caused a significant decrease in 24-h BP (136.3 +/- 4.0/82.8 +/- 2.5 v 131.6 +/- 3.2/80.0 +/- 2.3 mm Hg). The alcohol-induced hypotension at 2-4 h after ingestion was enhanced by prazosin (-18.0 +/- 3.7/-11.8 +/- 2.7 v -24.4 +/- 4.9/-17.8 +/- 2.8 mm Hg, P < .05 for diastolic BP). These results suggested that inhibition of the sympathetic nervous system with alpha1-blockers accentuates alcohol-induced hypotension. Ingestion of alcohol may cause a marked BP reduction in hypertensive Orientals treated with alpha1-blockers.  相似文献   
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Purpose

To determine if a 20 % reduction in the contrast material dose is acceptable in the CT evaluation of patients with head and neck malignancy.

Materials and methods

Sixty consecutive patients (mean age 67 years) with head and neck malignancy underwent contrast-enhanced CT according to two different protocols: protocol A (80 mL of contrast material administered at an injection rate of 1.5 mL/s) and protocol B (100 mL at 1.9 mL/s). The enhancement of anatomical structures and detectability of metastatic nodes were compared between the two protocols. Pathologic analysis of the surgical resection served as the reference standard.

Results

CT numbers of the anatomical structures were not significantly different between the two protocols. Mean sensitivity (64 and 77 % for protocols A and B, respectively), specificity (78 and 84 %), and accuracy (74 and 83 %) tended to be higher for protocol B than for A, but no significant difference was found.

Conclusion

Reducing the contrast material dose by 20 % did not significantly impair the enhancement of anatomical structures or the detection of metastatic cervical lymph nodes. Radiologists should therefore consider reducing the contrast material dose used in head and neck CT.  相似文献   
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Ureteral endometriosis is a rare but important clinical problem that requires early detection and treatment. The urinary tract is affected in approximately 2% of women with endometriosis. Even though the bladder is the most frequent urinary tract organ affected in these patients,the ureter is also affected in 10-40% of the cases, thus requiring immediate clinical attention. The majority of endometrial lesions is typically located in the lower segment of the ureter and is often difficult to differentiate between endometriosis and malignancy. Ureteral endmetriosis should be considered for women with hydronephrosis. In this report we present one clinical case of mixed-type ureteral endometriosis. A 37-year-old woman was referred to our hospital due to left hydronephrosis. Contrast-enhanced CT scan confirmed left hydronephrosis and also showed a solid mass at the left lower ureter. Retrograde pyelography revealed stenosis of the left lower ureter and Renogram revealed severely impaired renal function. Laparoscopic nephroureterectomy was performed. Pathologically, mixed-type endometriosis of the left ureter was diagnosed.  相似文献   
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