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1.
In Kobe University Hospital, a new method for endoscopic mucosal resection (EMR) using insulated‐tip electrosurgical knife (IT‐EMR) for early gastric cancer (EGC) was introduced from November 2001. To achieve an effective and safe IT‐EMR procedure, we use a high‐frequency surgical unit for cutting and coagulation (ERBOTOM ICC 200) with automatically controlled cutting mode (ENDOCUT). In this study, we show not only our results of IT‐EMR for EGC in comparison with those of the conventional strip biopsy method, but also the optimal conditions for the apparatus of a high‐frequency surgical unit to prevent complications such as bleeding and perforation.  相似文献   
2.
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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Abstract A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature.  相似文献   
6.
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   
7.
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor.  相似文献   
8.
Transesophageal echocardiography was conducted to determine the systolic pattern of the anterior mitral leaflet in patients with flat chest, and to differentiate it from that associated with mitral valve prolapse. The fronto-sagittal index (an index of chest flattening) was determined in 50 subjects using chest radiographs, and was used to classify them into a flat chest group (index < 0.38, n = 28) and a normal chest group (index ≥ 0.38, n = 22). We then used transesophageal echocardiography to examine the anterior leaflet in these subjects. A significant positive correlation was observed between the fronto-sagittal index and the short-to long-axis diameter ratio of the left ventricle in all patients. These parameters, and the left atrial dimension were lower in the flat than the normal chest group. The clear zone area of the anterior leaflet during mid-to late-systole was significantly larger in the flat chest group. However, no intergroup differences existed in the rough zone area of the anterior leaflet or in the middle scallop area of the posterior leaflet. Mitral regurgitation was observed in 20 and 12 subjects in the flat and normal chest groups, respectively. The maximum mitral regurgitant area did not differ between the two groups. The clear zone area of the anterior leaflet increased significantly following inhalation of amyl nitrite in 22 subjects of both groups, but the other areas did not increase. The mitral regurgitant area decreased or disappeared after amyl nitrite at a similar rate in each group. Thus, the decrease in the antero-posterior dimension of the thorax in subjects with flat chest affects the systolic pattern of the clear zone of the anterior leaflet more than that of the rough zone of the anterior leaflet or the posterior leaflet. This systolic pattern in such patients differs from that associated with mitral valve prolapse.  相似文献   
9.
SUMMARY: A comparative immunohistological study was performed for the glomerular deposition of complements (C1q and C3c), fibrin/fibrinogen‐related antigen (FRA), the expression of intercellular adhesion molecule‐1 (ICAM‐1), and the infiltration of leucocytes bearing β2 integrins (leucocyte function associated antigen‐1 (LFA‐1), complement receptor 3 (CR3) and complement receptor 4 (CR4)) on renal biopsy specimens from 49 cases with Henoch‐Schoenlein purpura nephritis (HSPN), and 49 age‐matched cases with immunoglobulin A nephropathy (IgAN). the glomerular expression of ICAM‐1 was signifcantly correlated with the glomerular infiltration of leucocyte function associated antigen (LFA)‐1+ leucocytes in both diseases, and with that of CR3+ leucocytes in HSPN. the expression of ICAM‐1 was closely localized with the infiltration of LFA‐1+ leucocytes in the study with double immunostaining. the incidence and intensity of glomerular deposition of FRA were significantly higher in HSPN than in IgAN (P< 0.001), and those of C3c were significantly lower in HSPN than in IgAN (P< 0.001). the glomerular deposition of FRA was significantly correlated with the glomerular infiltration of CR4+ leucocytes in HSPN (P<0.05) but not in IgAN. In contrast, the glomerular deposition of C3c was significantly correlated with the glomerular infiltration of CR4+ leucocytes in IgAN (P<0.05), but not in HSPN. Studies with double immunostaining revealed a close association of CR4+ leucocytes with FRA deposition in HSPN and with C3c deposition in IgAN, respectively. the number of glomerular leucocytes bearing β2 integrins was significantly correlated with urinary protein at the time of renal biopsy in both diseases. These results suggested the differential roles of β2 integrins in the induction of glomerular injury in HSPN and IgAN. the ICAM‐1/LFA‐1 interaction may commonly be involved in the glomerular infiltration of leucocytes in both diseases. the ICAM‐1/CR3 interaction may be involved only in HSPN. Complement receptor 4 may function as a fibrin/fibrinogen receptor in HSPN, while CR4 may function as a complement receptor in IgAN.  相似文献   
10.
The vacuolating cytotoxin and urease secreted by Helicobacter pylori are thought to be virulent factors. Because vacuolation is potentiated by the presence of ammonium ion, which is produced by urease in vitro, it is of interest to examine whether cytotoxin and urease work reciprocally in the development of atrophic gastritis or duodenal ulcer. In the present study, patients (all H. pyloripositive) were divided into four groups: mild atrophic gastritis (group 1; nine patients), severe atrophic gastritis (group 2; 36 patients), duodenal ulcer with mild atrophic gastritis (group 3; 19 patients) and duodenal ulcer with severe atrophic gastritis (group 4; 12 patients). Cytotoxin production and urease activity of H. pylori isolated from these patients were analysed. Cytotoxin production was observed in four of nine (44.4%), 28 of 36 (77.8%), 11 of 19 (57.9%) and eight of 12 (66.7%) isolates from groups 1, 2, 3 and 4, respectively. Cytotoxin-producing H. pylori isolates were found significantly more in patients with severe atrophy than in patients with mild atrophy (P= 0.048). The mean of relative activity of cytotoxin in H. pylori isolate was 1. 6. ± 2. 3, 7. 9. ± 7. 4, 5. 8. ± 6. 0 and 9. 0 ± 9. 1 in groups 1, 2, 3 and 4, respectively. Helicobacter pylori isolates from severe atrophy or duodenal ulcer patients in groups 2 or 4 possessed significantly higher activity than those from non-ulcer patients in group 1 (P= 0.017 and 0.030, respectively). The mean of urease activity was 8. 6 ± 4. 6, 10. 0 ± 5. 9, 10. 0 ± 8. 5 and 11. 2 ± 7. 7 IU/mg in groups 1, 2, 3 and 4, respectively. These differences indicated no statistical significance. In each H. pylori isolate, the production of cytotoxin and urease were independent, which indicated that there was no reciprocal effect between them in vivo. Thus, cytotoxin-producing H. pylori isolates were more prevalent in patients with severe atrophic gastritis and the cytotoxin activities of H. pylori isolates from the patients with severe atrophic gastritis or duodenal ulcer were much higher than those from the patients with mild atrophic gastritis, which suggested that vacuolating cytotoxin may be a disease-inducing factor.  相似文献   
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