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91.
A 47-year-old Japanese woman in whom obstructive jaundice had already been diagnosed, was found to have a dome-shaped elevated tumor approximately 3 cm in diameter located in the area very close to the papilla of Vater on endoscopical and radiographical investigations. Histopathologically, the resected tumor was composed mainly of solid nests of atypical argyrophilic cells, and partially of an area of well differentiated tubular adenocarcinoma, showing mutual transition in the mucosal layer. Both immunohistochemical and ultrastructural analyses confirmed the difference in character of tumor cells between these two areas: neuroendocrine cell carcinoma and tubular adenocarcinoma of common type in the intestine. To the best of our knowledge, this is only the third case reported to be a coexisting malignant carcinoid tumor and adenocarcinoma arising in the periampullary region.  相似文献   
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INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs.  相似文献   
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Substance P containing nerve fibers in rectal mucosa of ulcerative colitis   总被引:3,自引:0,他引:3  
BACKGROUND AND PURPOSE: The intestine is rich in peptidergic innervation, which modulates mucosal immune responses. Among neuropeptides, substance P (SubP) has received considerable attention for stimulatory effects on various immunocytes in inflammatory diseases. In our prior study, we demonstrated increased innervation of SubP containing nerve fibers (SubP fibers) in ulcerative colitis (UC) surgically resected colonic specimens. In the present study, we examined the alterations of SubP fibers among various subgroups of UC, divided according to clinicopathologic features. METHODS: Distribution of SubP fibers were examined immunohistochemically in the rectal biopsy specimens of UC. The UC group was further divided into subgroups according to six clinicopathologic parameters. The linear density of SubP fibers was measured by digitalized morphometry for quantitative analysis. RESULTS: Multivariate analysis revealed significant correlations between linear density of SubP fibers vs.activity of diseases and total dose of prednisolone. Linear density was significantly increased in active cases of UC (active UC, 22.6±1.6 μm/1,000 μm 2;vs.inactive UC, 12.2±0.8 μm/1,000 μm 2;P<0.01). Furthermore, the increase was pronounced in cases that showed persistent inflammation and, accordingly, needed a high dose or continuous administration of prednisolone. CONCLUSION: Alterations in SubP fibers appear to play an important role in the pathogenesis of UC.  相似文献   
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An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.  相似文献   
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Purpose

To evaluate the surgical outcomes of small-gauge vitrectomy with subretinal injection of recombinant tissue plasminogen activator (rt-PA) for a submacular hemorrhage caused by a ruptured retinal arterial macroaneurysm (RAM).

Methods

Non-comparative, consecutive case-series performed at two ophthalmological institutions. We examined 22 eyes of 22 patients with a submacular hemorrhage associated with a RAM but without a preretinal or sub-internal limiting membrane hemorrhage at the fovea. During 25-gauge vitrectomy, approximately 4000–8000 IU of rt-PA was injected subretinally, followed by the injection of air or 10 % sulfur hexafluoride as a tamponade. The patients maintained an upright position for 1 hour, then turned to a facedown position for 1 to 3 days. The best-corrected visual acuity (BCVA) and postoperative complications were evaluated.

Results

The average interval from the onset of symptoms to surgery was 8.4?±?7.6 days, and the average size of the subretinal hemorrhage was 3.4?±?1.0 disc diameters. The submacular hemorrhage was displaced from the foveal area in all eyes after 1 week. The mean baseline BCVA was 1.41?±?0.41 logMAR units, and it improved to 0.91?±?0.43 at 1 month and to 0.64?±?0.45 at the final visit (P?=?0.0001, P?<?0.0001 respectively). A macular hole was detected intraoperatively in two eyes and postoperatively in two eyes, and both were closed by internal limiting membrane peeling or a second vitrectomy.

Conclusions

Small-gauge vitrectomy with subretinal rt-PA injection and gas tamponade were effective in displacing a submacular hemorrhage associated with a RAM.
  相似文献   
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Journal of Gastroenterology - Hepatitis B virus (HBV) is one of the most prevalent chronic viral infections that causes chronic hepatitis B (CHB). In Japan, genotypes B and C account for most of...  相似文献   
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Objective For patients with Gaucher disease (GD), a rare, inherited lysosomal storage disease, obtaining a definitive diagnosis is currently time-consuming and costly. A simplified screening method to measure the glucocerebrosidase (GBA) activity using dried blood spots (DBS) on filter paper has recently been developed. Using this newly developed screening method, we evaluated real-world GD screening in patients suspected of having GD. Methods This multicenter, cross-sectional, observational study with a diagnostic intervention component evaluated real-world screening in patients suspected of having GD based on their clinical symptoms and a platelet count <120,000/μL. The endpoint was the number of patients with low GBA activity determined using DBS. Results In 994 patients who underwent initial DBS screening, 77 had low GBA activity. The assay was not repeated in 1 patient who was diagnosed as having a high possibility of GD due to clinical symptoms, and a further 21 patients completed the study without undergoing the second assay. Of the remaining 55 patients who had 2 DBS assays performed, 11 had a low GBA activity in both assays. Overall, DBS screening identified 12 (1.2%) patients with a low GBA activity, a proportion consistent with prior screening studies. Conclusion These results suggest that the simplified DBS method was less burdensome to patients, was easily utilized by many physicians, and could be a useful first-tier screening assay for GD prior to initiating burdensome genetic testing.  相似文献   
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