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1.
Background and Aim: Duodenal lymphangitis carcinomatosa has been sporadically described, but so far little attention has been paid to duodenal lymphangitis carcinomatosa. Methods: Four cases with duodenal lymphangitis carcinomatosa were endoscopically and histologically examined. Results: The four cases exhibited multiple polypoid lesions along the Kerckring's folds and/or were covered by characteristically granular, non‐ulcerated mucosa upon thickening. The granularity seems to been caused by dilated lymph vessels containing the carcinoma cells. The lesions were microscopically characterized by: (i) involvement of lymph vessels located in the upper portion of the lamina propria; (ii) no inflammatory changes; and (iii) no desmoplastic changes. Primary sites were thought to be the stomach in case 1, the pancreas in cases 2 and 4, and unknown in case 3. All patients died within 6 months after admission or endoscopic examination. Conclusions: As duodenal lymphangitis carcinomatosis shows characteristic endoscopic appearance, endoscopic diagnosis is not difficult. We should realize that the lesion represents extremely poor prognosis, and it should be distinguished from ordinary metastatic duodenal carcinoma.  相似文献   
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Background: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. Methods: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. Results: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal‐looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal‐looking surface or non‐elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable‐sized vacuoles, and were related to lymph follicles. Conclusion: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.  相似文献   
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BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
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FK070, a thromboxane A2 (TXA2) receptor antagonist/TXA2 synthetase inhibitor, was given orally to healthy male volunteers in a single-and multiple-dose study. In the single-dose study (200, 300, 400 mg), the area under the plasma concentration—time curve (AUC) and the maximum plasma concentration (Cmax) increased non-linearly with dose, while the mean elimination half-life (t1β) was essentially unchanged (3.9-7.3 h). Recovery of the unchanged drug in the urine was 12–25%. Cmax and AUC as determined with 200 mg of drug after a meal decreased by about 60 and 30%, respectively. Ex-vivo platelet aggregation in the plasma by a TXA2 analogue, U46619, was almost completely inhibited within 1 h, after all doses of drug, with a significant dose-dependent inhibition maintained for 8 h or more, which was much longer than was expected from drug plasma concentration. The aggregation by adenosine diphosphate (ADP) was inhibited to a lesser extent. FK070 also inhibited TXA2 synthetase as evidenced by decreased production of TXB2 and reciprocally increased production of 6-keto-prostaglandin F in the serum during ex-vivo whole blood coagulation. These effects peaked 1 h after drug and lasted until 4 h with the higher doses. In the multiple-dose study (300 mg, twice a day, after meals for 6.5 days), drug concentrations in the plasma were well fitted to a three-compartment open model with first-order absorption. FK070 afforded extensive inhibition of platelet aggregation by U46619 throughout the administration period, with a significant inhibition lasting as long as 48 h after conclusion of administration. No clearly drug-related changes were found in routine laboratory tests, subjective and objective findings, or vital signs. FK070 was concluded to be well tolerated and to provide long-lasting blockade of TXA2 receptors, and plasma concentration-dependent inhibition of TXA2 synthetase in the platelets.  相似文献   
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Aim: Differential diagnosis, including the respective distinctions between benign and malignant tumors, follicular and papillary neoplasms, and follicular adenoma and follicular carcinoma, are always required in clinical practice, because therapeutic strategy largely depends on the diagnosis made. Methods: The present study describes a novel approach to obtaining clinically useful markers by means of the simultaneous comparison of multiple molecules using tissue array analysis. The markers examined in this study include galectin‐3, CD44v6, p53, HBME‐1, maspin and S100A4, which were reportedly useful for making these distinctions in association with metastasis and invasion. A total of 45 cases of thyroid tumors (seven adenomatous goiters, 16 follicular adenomas, 12 follicular carcinomas and 10 papillary carcinomas) were analyzed. Results: The results demonstrated the following suggestive phenotypes: galectin‐3, HBME‐1 and maspin+ as benign lesions, galection‐3, HBME‐1+ and maspin as follicular carcinoma, and galectin‐3+, HBME‐1+ and maspin+ as papillary carcinoma. Conclusions: The expression of the molecules was assessed in each case and the expression profiles were compared. Useful multiple molecules were selected for each distinction and were correlated with each other. To understand the complex relationship, a logistic regression model was constructed. These results suggested that combined analysis of multiple molecules enhanced the differential diagnostic accuracy.  相似文献   
8.
The aim of the present study was to clarify whether bile acids influence chemiluminescence (CL) in the liver in vivo. Hepatic CL was determined on the surface of the liver of anaesthetized rats by using a photon counter. In normal rats, hepatic CL was significantly decreased 30 min after enteral administration of chenodeoxycholic acid (CDCA) or deoxycholic acid (DCA), but returned to its initial level 3 h later, after part of the CDCA administered was metabolized. Ursodeoxycholic acid (UDCA) and cholic acid had no effect on CL. In contrast, hepatic CL was markedly increased 30 min after CDCA or DCA administration in rats given either buthionine sulphoximine (BSO), an inhibitor of γ-glutamylcysteine synthetase, or diethyldithiocarbamate (DDC), an inhibitor of both superoxide dismutase and glutathione peroxidase. Chenodeoxycholic acid further increased the CL of BSO- or DDC-treated rats during inhalation of oxygen via a tracheal cannula. Coadministration of UDCA eliminated the effects of CDCA on the hepatic CL of normal and BSO- or DDC-treated rats with or without oxygen inhalation. We conclude that cytotoxic bile acids, such as CDCA, increase CL in the antioxidants-depleted or oxidative-stressed liver in vivc, but that UDCA prevents CDCA from developing CL.  相似文献   
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A 60‐year‐old man underwent routine colonoscopy, and was noted to have a pedunculated polyp in the sigmoid colon. The pathologic diagnosis was adenoma, and due to patient’s personal circumstances, the lesion was left untreated. The colonoscopic examination was repeated 4 years and 11 months later, to find that the polyp had transformed into an elevated lesion with irregularly depressed surface. The patient was diagnosed as having early sigmoid cancer, and underwent sigmoidectomy. The histologic examination of the excised specimen revealed well‐differentiated adenocarcinoma with invasion into the submucosal layer. Through studying the natural course of colon cancer, it has become known that the advanced cancers commonly develop from polyps with short pedicles (sessile polyps). This case represents an early sigmoid cancer developed from a pedunculated polyp, which differs from the current mainstream concept of ‘polyp‐cancer sequence of colon cancer.’  相似文献   
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