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991.
Ultrasonography should be used for screening of hepatocellular carcinoma, but there are few reports on the relationship between liver ultrasonographic findings and the development of hepatocellular carcinoma (HCC). Using prospective follow-up studies, we examined the role of liver with a hypoechoic nodular pattern as a high-risk factor in HCC. The study was performed by follow-up on 593 patients with chronic liver disease recorded at our hospital. The ultrasonographic pattern of the liver parenchyma was classified either as a small or large hypoechoic nodular pattern or as a nonnodular pattern. Patients were followed up from the time of initial ultrasonographic examination (1985–1987) until January 1, 1991. During the follow-up period (average, 4.2 years, range, 0.3–6.0 years), 62 patients were found to have HCC (12%). Patients whose livers showed small or large hypoechoic nodular pattern had a significantly higher risk of HCC than did patients whose livers showed a nonnodular pattern (rate ratios were 14.0 and 20.0, respectively, adjusted for age, sex, hepatitis virus markers, ICG R15, α-fetoprotein concentration, and ultrasonographic pattern of the liver). Liver showing a hypoechoic nodular pattern is a major risk factor in HCC.  相似文献   
992.
993.
A patient underwent radiofrequency (RF) catheter ablation for a drug-refractory ventricular tachycardia, but RF energy application at an endocardial site of the left ventricular outflow tract and at the left sinus of Valsalva could not eliminate the tachycardia. The earliest ventricular activation during the arrhythmia, which preceded the onset of the QRS complex by 32 ms, was found within the great cardiac vein and complete elimination of the tachycardia was finally achieved with RF application at that site.  相似文献   
994.
Steatosis is one of the most common liver diseases and is associated with the metabolic syndrome. A line of evidence suggests that peroxisome proliferator-activated receptor (PPAR) alpha and PPARgamma are involved in its pathogenesis. Hepatic overexpression of PPARgamma1 in mice provokes steatosis, whereas liver-specific PPARgamma disruption ameliorates steatosis in ob/ob mice, suggesting that hepatic PPARgamma functions as an aggravator of steatosis. In contrast, PPARalpha-null mice are susceptible to steatosis because of reduced hepatic fatty acid oxidation. PPARgamma with mutations in its C-terminal ligand-binding domain (L468A/E471A mutant PPARgamma1) have been reported as a constitutive repressor of both PPARalpha and PPARgamma activities in vitro. To elucidate the effect of co-suppression of PPARalpha and PPARgamma on steatosis, we generated mutant PPARgamma transgenic mice (Liver mt PPARgamma Tg) under the control of liver-specific human serum amyloid P component promoter. In the liver of transgenic mice, PPARalpha and PPARgamma agonist-induced augmentation of the expression of downstream target genes of PPARalpha and PPARgamma, respectively, was significantly attenuated, suggesting PPARalpha and PPARgamma co-suppression in vivo. Suppression of PPARalpha and PPARgamma target genes was also observed in the fasted and high-fat-fed conditions. Liver mt PPARgamma Tg were susceptible to fasting-induced steatosis while being protected against high-fat diet-induced steatosis. The opposite hepatic outcomes in Liver mt PPARgamma Tg as a result of fasting and high-fat feeding may indicate distinct roles of PPARalpha and PPARgamma in 2 different types of nutritionally provoked steatosis.  相似文献   
995.
Percutaneous management of bile duct injuries after cholecystectomy   总被引:2,自引:0,他引:2  
Intraoperative biliary tract injuries are relatively uncommon, but are a cause of significant morbidity and mortality. We have repaired open biliary tract injuries found postoperatively in three patients without reoperation by percutaneous intervention. In two cases, biliary stents were placed percutaneously across the injured portion of the bile duct. For this procedure, a unique coaxial guidewire technique was used. The bile leaks resolved soon after insertion of the biliary stents. In one patient, an expandable metallic biliary endoprosthesis was inserted, and the temporary stent was removed. This patient had no signs or symptoms of cholangitis or biliary obstruction at the 6-year follow-up. The other patient died of heart failure soon after reconstruction. In the last patient, a biliary drain was inserted through the injured duct via the biliocutaneous fistula. In this case, biliary drainage alone resulted in resolution of the bile leak, because the injury was partial without a stricture. This patient was well at the 3-year follow-up. Percutaneous management of bile duct injuries is an alternative in selected patients.  相似文献   
996.
PURPOSE: We retrospectively analyzed prognostic factors for surgical resection and intraoperative radiation therapy to identify indicators for this treatment strategy. METHODS: Thirty-nine consecutive patients with locally recurrent colorectal cancer who underwent surgical resection with intraoperative radiation therapy from January 1, 1987, to June 30, 1999, were analyzed. The mean electron energy was 10.5 MeV and the mean intraoperative radiation dose was 22.6 Gy. Kaplan-Meier survival estimates were obtained for the 37 patients who recovered postoperatively. Prognostic factors were analyzed univariately by log-rank test and multivariately by Coxs proportional hazards model. RESULTS: Three-year cumulative survival was 44 percent (standard error = 11) for 26 patients free of unresectable distant metastasis who underwent surgical resection and intraoperative radiation therapy for pelvic recurrence of colorectal cancer, but none of the 11 patients with unresectable distant metastasis survived 3 years. Preoperative prognostic factors which were significant on univariate and multivariate analysis were unresectable distant metastasis (P = 0.001) and elevated preoperative serum CA 19–9 (P = 0.02). Patients with synchronous resection of local recurrence and distant metastasis had a significant survival advantage over those without resection of metastases (P = 0.02). Univariate analysis in a subgroup of 26 patients without unresectable distant metastasis revealed pain (P = 0.0003) to be a useful preoperative prognostic indicator, whereas tumor fixation (P = 0.01) and amount of residual tumor after surgical resection (P = 0.01) were significant intraoperative and postoperative factors, respectively. Fluorouracil-based postoperative systemic chemotherapy produced a significant survival benefit (P = 0.04). CONCLUSIONS: Patients with unresectable distant metastasis are not suitable candidates for surgical resection and intraoperative radiation therapy, whereas those with resectable metastasis are potential candidates. Intraoperative radiation therapy may be less useful for patients with pain, elevated preoperative CA19–9, fixed tumors, or gross residual tumor after surgical resection. Multimodal treatment strategies combining preoperative and/or postoperative external beam radiation therapy and intraoperative radiation therapy with fluorouracil-based systemic chemotherapy are recommended for patients with these indicators.  相似文献   
997.
In Japan the composition of gallstones is changing rapidly from the once-predominant brownpigment stones to cholesterol ones. The present work was undertaken to clarify the mechanism of cholesterol supersaturated bile production in Japanese patients with cholesterol gallstones. In 26 non-obese and normolipidemic patients (11 with cholesterol gallstones, 8 with black- or brown-pigment gallstones, 7 without gallstones) a liver biopsy and hepatic bile were surgically obtained under standardized conditions. The cholesterol saturation of hepatic bile was significantly higher in cholesterol gallstone patients than in gallstone-free controls (195 ±10 vs. 146 ±8%, respectively; P < 0.01). The microsomal activities of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme for cholesterol synthesis, cholesterol 7 α-hydroxylase, the rate-limiting enzyme for bile acid synthesis, and 7 α-hydroxy-4-cholesten-3-one 12 α-hydroxylase (12 α-hydroxylase), the rate-limiting enzyme for cholic acid synthesis, were assayed simultaneously in the same subjects. There were positive correlations between HMG-CoA reductase and cholesterol 7 α-hydroxylase activities (Rs = 0.62, P < 0.005), and between cholesterol 7 α-hydroxylase and 12 α-hydroxylase activities (Rs = 0.44, P < 0.05) in all subjects, irrespective of the existence of gallstones. The activities of the three rate-limiting enzymes did not differ significantly among the three groups (cholesterol stone, pigment stone and stone-free). In conclusion, the cholesterol supersaturation of hepatic bile in nonobese and normolipidemic Japanese patients with cholesterol gallstones does not result from an increased hepatic cholesterol synthesis or a decreased bile acid synthesis. This study was supported in part by a Grant-in-Aid for Scientific Research (No. 02454226) from the Ministry of Education, Science and Culture of Japan, and a grant from University of Tsukuba Project Research.  相似文献   
998.
Pulmonary artery obstruction is a rare complication of acute thoracic aortic dissection. A 74-year-old woman was admitted to hospital with respiratory distress. Computed tomography scan showed right pulmonary artery occlusion and a thoracic aortic dissection of the Stanford A type. Lung perfusion scan revealed a defect in the entire right lung field. These findings mimicked acute pulmonary thromboembolism accompanying aortic dissection. On the other hand, pulmonary angiography revealed a round smooth defect of the right pulmonary artery, indicating an extrinsic compression. The patient finally died of cardiac tamponade. Autopsy disclosed that the right pulmonary artery was compressed by a hematoma in the adventitial space around the pulmonary artery. Such a mechanism of pulmonary artery obstruction caused by acute aortic dissection is unique, and is distinct from that caused by chronic non-dissecting aortic aneurysms, which themselves compress the pulmonary arteries. This complication inevitably follows aortic rupture; therefore, emergency operation to repair the dissected aorta must be performed to avoid the following catastrophic event.  相似文献   
999.
The relationship between Helicobacter pylori (H. pylori) and gastric diseases (e.g. peptic ulcer, MALT lymphoma, and stomach cancer) has been widely accepted. Recent studies have also suggested an association between H. pylori infection and idiopathic thrombocytopenic purpura (ITP). In this study, an H. pylori eradication treatment was administered to 20 ITP patients and elucidated for its effectiveness. Among those 20 patients, H. pylori infection was confirmed in 17 (85%) through a C14 urea breath test, a rapid urease test, or a culture examination of a biopsied sample obtained by gastrointestinal endoscopy. Although the other 3 were negative to H. pylori, the H. pylori eradication treatment was also attempted because no other effective treatments had been established at the time of this study. In the H. pylori eradication treatment, lansoprazole (LPZ) 60 mg bid, amoxicillin (AMPC) 1500 mg bid, and clarithromycin (CAM) 400 mg bid were given to each patient for 7 days. For 4 cases, CAM was replaced with metronidazole (MNZ) 750 mg bid. The patients whose H. pylori infection was not eradicated after the first treatment received the re-eradication treatment with LPZ 60 mg bid, AMPC 1500 mg bid, and MNZ 750 mg bid for 7 days. After the treatments, the success of eradicating H. pylori was confirmed in all 17 H. pylori positive patients. In addition, platelet recovery was obtained in 11/20 patients (55%), which included 2 H. pylori negative patients and 2 patients whose H. pylori eradication was not successful after the first treatment. No relationship was found between the eradication effectiveness and the following clinical parameters: age, gender, previous therapies, disease duration, presence of anti-nucleus antibody, endoscopic atrophic change in the stomach, or kinds of antibiotics used for the treatment. These results support the efficacy of an H. pylori eradication treatment for ITP patients. A noteworthy result of this study was that an increase of platelet count was observed not only in H. pylori positive ITP patients, but also in 2 out of 3 H. pylori negative ITP patients after H. pylori eradication. Further studies are required to elucidate the efficacy of H. pylori eradication therapy in the patients negative for H. pylori.  相似文献   
1000.
Background We examined the current status and diagnostic accuracy of currently available techniques for tumor staging and assessed treatment outcomes in patients with superficial esophageal cancer who received esophaguspreserving therapy, such as endoscopic mucosal resection (EMR) alone or combined with chemoradiotherapy (CRT). Methods In 274 patients with superficial esophageal cancer, we examined the depth of tumor invasion and the degree of lymph node metastasis by means of endoscopy, magnifying endoscopy, endoscopic ultrasonography (EUS), computed tomography (CT), and cervical and abdominal ultrasonography (US). We compared treatment outcomes among treatment groups according to the depth of tumor invasion. Results The rates of correctly diagnosing the depth of tumor invasion were 89.6% on conventional endoscopy, 90.1% on magnifying endoscopy, and 85% on scanning with a high-frequency miniature ultrasonic probe (miniature US probe). Diagnostic accuracy for the m3 or sm1 cancers was poor. Magnifying endoscopy allowed invasion to be more precisely estimated, thereby improving diagnostic accuracy. However, lesions that maintained their surface structure despite deep invasion were misdiagnosed on magnifying endoscopy. A miniature US probe was useful for the assessment of such lesions. The diagnostic accuracy of EUS for lymph node metastasis was 83%, with a sensitivity of 76%. The sensitivity of CT was 29%, and that of cervical and abdominal US was 17%. Patients with m1 or m2 cancer had good outcomes after esophagus-preserving therapy. Although there were no significant differences in survival rates, many patients with sm2 or sm3 cancer who received CRT died of their disease. Nodal recurrence was diagnosed by EUS. In patients who received CRT, the time to the detection of recurrence was slightly prolonged. Conclusions Long-term follow-up at regular intervals is essential in patients with m3 or sm esophageal cancers who receive esophagus-preserving treatment. At present, EUS is the most reliable technique for the diagnosis of lymph node metastasis and is therefore essential for pretreatment evaluation as well as for follow-up. Earlier detection of recurrence at a level that would potentially salvage treatment remains a topic for future research. Review articles on this topic also appeared in the previous issue (Volume 4 Number 3). An editorial related to this article is available at .  相似文献   
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