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991.
Cholangiographic findings of early-stage extrahepatic bile duct carcinoma   总被引:1,自引:0,他引:1  
BACKGROUND: To clarify the cholangiographic findings of early-stage (T1, tumor confined to the mucosal or fibromuscular layer) extrahepatic bile duct carcinoma. METHODS: Cholangiographic images were retrospectively analyzed without other information in 55 patients with extrahepatic bile duct carcinoma who underwent surgical treatment. Tumor stages were T1 (n = 10). T2 (n = 17), and T3 (n = 28). Cholangiographic findings were classified as "diffuse sclerosis," "stenosis," "papillary polypoid filling defect," or "nodular polypoid filling defect". "Papillary polypoid filling defect" was the term used when the width of the base was smaller than the width of the polypoid filling defect. RESULTS: T1 patients showed papillary polypoid filling defects (n = 8) or nodular polypoid filling defects (n = 2) on cholangiography. When cholangiography showed papillary polypoid filling defects, 8 of the 14 resected patients showed T1 stage tumor histologically. CONCLUSIONS: In this study, 57% (8/14) of resected patients with papillary polypoid filling defects showed T1 stage tumor. No T1 stage tumor showed stenosis or diffuse sclerosis.  相似文献   
992.
A 72-year-old man with acute myelocytic leukemia (AML) suffered relapsing massive bleeding from gastric angiodysplasia. He was referred to our hospital in February 2000 because of anemia and thrombocytopenia. He had hypercellular (nucleated cell count 42 x 10(4)/microl) bone marrow with 90% myeloblasts, and AML (FAB: M1) was diagnosed. Remission induction therapy by BHAC/DM regimen failed. While considering subsequent regimens, massive hematemesis from a solitary gastric angiodysplasia developed. In April, after re-remission induction by CAG regimen, hematemesis from the same lesion reccurred. Hemostasis was achieved by topical transendoscopic injection of polidocanol. After achievement of complete remission by CAG therapy, he was treated on an outpatient basis. In July, his AML relapsed and he was treated mainly by transfusion therapy. In September, hematemesis recurred resulting in hemostasis with the same procedure. In the course of endoscopic injections, his mucosal lesion became difficult to observe. Gastric angiodysplasia is occasionally observed in the elderly, but massive bleeding is a rare complication. In this case, topical injection of polidocanol was an effective procedure for the massive bleeding from it even in an elderly patient with the complication of thrombocytopenia due to AML.  相似文献   
993.
The etiopathogenesis of extrahepatic manifestations including vasculitis in the context of HCV infection is still unknown. We report a case with lethal extrahepatic manifestations due to chronic hepatitis C virus (HCV) infection. The patient presented leukocytoclastic vasculitis, sensorimotor neuropathy and membranoproliferative glomerulonephritis with positive rheumatoid factor but lacked cryoglobulin. Hypocomplementaemia and deposition of IgM and C3 in the vascular lesion and glomeruli suggested that immune complex disease played a role in the pathogenesis of extrahepatic manifestations independent of cryoglobulin. Although HCV was successfully eliminated by treatment with interferon alpha, she died of cryptococcal infection.  相似文献   
994.

Background

IgG4 production is regulated by type 2 (IL-4 and IL-13) and regulatory (IL-10) cytokines involved in the pathophysiology of chronic rhinosinusitis (CRS). We sought to determine the pathophysiological characteristics of IgG4-positive cells in sinonasal tissues in CRS, especially eosinophilic CRS (ECRS).

Methods

IgG4-positive cells in uncinate tissues (UT) and nasal polyps (NP) were examined by immunohistochemistry. Associations between the number of IgG4-positive cells and clinicopathological factors were analyzed. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of IgG4-positive cells in tissue that can predict the post-operative course.

Results

IgG4 was mainly expressed in infiltrating plasma and plasmacytoid cells, and the number of IgG4-positive cells was significantly higher in NP, especially those from severe ECRS patients, than in UT. In CRS patients, the number of IgG4-positive cells significantly and positively correlated with blood and tissue eosinophilia, radiological severity, and serum level of total IgE. The number of infiltrating IgG4-positive cells was significantly higher in patients with a poor post-operative course (sustained sinus shadow 6 months after surgery) than in those with a good one. The number of IgG4-positive cells in NP could discriminate patients with a good or a poor post-operative course (area under the curve: 0.769). Also, 73.3% sensitivity and 82.5% specificity were achieved when the cut-off value was set at 17 cells/high-power field.

Conclusions

Our results suggest that the local expression of IgG4 on cells may be used as a biomarker that reflects the pathophysiology of CRS, including the post-operative course.  相似文献   
995.
The present study was conducted to examine the effect of eicosapentaenoic acid supplements on pulse wave velocity (PWV) in patients with dyslipidemia as a prospective open-labeled study. Eicosapentaenoic acid supplements (1,800 mg/day) were prescribed to 40 patients, and diet therapy in consultation with a nutritionist was conducted in 44 patients as a control group. These interventions were continued for 12 months, and PWV and blood examinations were performed at the start and end of these interventions. PWV increased in the control group but not in the eicosapentaenoic acid group. After adjustment for age, gender, the initial PWV, and the changes in mean blood pressure during the study period, a general linear model univariate analysis post hoc comparison demonstrated that the change in PWV during the period of study was significantly larger in the control group (42 +/- 20 cm/s) than in the eicosapentaenoic acid group (-9 +/- 19 cm/s) (p<0.05). Thus, this preliminary study suggested that eicosapentaenoic acid supplements attenuate age-related increases in arterial stiffness in patients with dyslipidemia. A further study with a larger number of subjects is proposed to confirm this beneficial effect of eicosapentaenoic acid supplements on arterial stiffness.  相似文献   
996.
997.
To investigate the relationship between plasma levels and coronary vasodilation after administration of isosorbide dinitrate (ISDN), the plasma concentration and diarneters of six segments of the left coronary artery were measured before and after sublingual (SL) ISDN (5 mg) and left intracoronary (IC) administration of ISDN (3 mg) in 12 patients. After SL-ISDN, the systolic aortic pressure decreased with no significant concomitant changes in heart rate or diastolic aortic pressure. After IC-ISDN, all hemodynamic parameters showed significant changes, and these were greater after IC-ISDN than those after SL-ISDN. The individual mean vasodilation of six segments induced by SL- and IC-ISDN, were 23± 9 and 35± 11% (p<0.01), respectively. Before SL-ISDN, ISDN was not detected in plasma. After SL- and IC-ISDN, however, the plasma values of the ISDN were 36.1± 53.3 and 101.5± 90.0 ng/ml (p<0.01), respectively. Thus, both coronary vasodilative responses and plasma ISDN levels after IC-ISDN were significantly greater than those after SL-ISDN. However, neither the individual mean coronary vasodilation nor the hemodynamic changes correlated significantly with plasma ISDN levels. Consequently, with administration of the same dose, the coronary vasodilative response to ISDN did not correlate with plasma levels. Furthermore, IC-ISDN dilates coronary arteries more effectively than SL-ISDN.  相似文献   
998.
Blockade of brain melanin-concentrating hormone 1 receptor (MCH1R) significantly ameliorates fatty liver as well as obesity. However, the mode of action of this effect is unknown. This study examined the effect of a MCH1R antagonist in murine steatohepatitis models with and without obesity and clarified whether these pharmacological effects were attributed to anti-obesity effects. Steatohepatitis with concomitant obese phenotypes was developed after 52-week exposure to a high-fat diet, and steatohepatitis with reduced body weight was developed by exposure to a methionine- and choline-deficient diet for 10 days. Chronic intracerebroventricular infusion of a peptidic MCH1R antagonist reduced hepatic triglyceride contents and ameliorated steatohepatitis on histological observations in both mice models. Improvement of steatohepatitis was concomitant with amelioration of obese phenotypes such as hyperinsulinemia and hyperleptinemia in the case of the obese model, whereas body weight reduction was not associated with amelioration of steatohepatitis by the antagonist in the lean model. Reduction of hepatic gene expressions encoding cytochromes P450 4A was identified by treatment with the antagonist in both the obese and lean models. These results suggest that brain blockade of MCH1R could alleviate steatohepatitis independently from anti-obesity effects. In conclusion, MCH1R antagonist could have a new therapeutic potential for the treatment of human nonalcoholic steatohepatitis.  相似文献   
999.
A microsurgical technique was used in performing anterior hepatic segmentectomy and pancreatoduodenectomy with reconstruction of the posterior hepatic artery in a 64-year-old man with widespread bile duct cancer from the intrapancreatic bile duct over the hepatic hilus. The anterior hepatic artery was obviously involved and the posterior hepatic artery just behind common hepatic duct was very close to the cancer. Microsurgical anastomosis between the remnant gastroduodenal artery and the posterior hepatic artery at the hepatic hilus made it possible to preserve the posterior segment of the liver and to perform a curative resection of the cancer. The patient had pyrexia because of suprahepatic abscess after the operation, but the abscess drained spontaneously. Postoperative arteriogram showed neither obstruction nor kinking of the reconstructed artery. He was discharged 2 months after surgery and has been enjoying a normal quality of life for 10 months since, with no signs of recurrence. It is suggested that a microsurgical technique is useful for performing an accurate anastomosis with good patency that allows not only a safe but also a highly curative operation for advanced bile duct cancer.  相似文献   
1000.
PTEN is a tumor suppressor gene but whether cancer can develop in all PTEN-deficient cells is not known. In T cell-specific PTEN-deficient (tPTEN−/−) mice, which suffer from mature T cell lymphomas, we found that premalignancy, as defined by elevated AKT and senescence pathways, starts in immature T cell precursors and surprisingly not in mature T cells. Premalignancy only starts in 6-week-old mice and becomes much stronger in 9-week-old mice although PTEN is lost since birth. tPTEN−/− immature T cells do not become tumors, and senescence has no role in this model because these cells exist in a novel cell cycle state, expressing proliferating proteins but not proliferating to any significant degree. Instead, the levels of p27kip1, which is lower in tPTEN−/− immature T cells and almost nonexistent in tPTEN−/− mature T cells, correlate with the proliferation capability of these cells. Interestingly, transient reduction of these cancer precursor cells in adult tPTEN−/− mice within a crucial time window significantly delayed lymphomas and mouse lethality. Thus, loss of PTEN alone is not sufficient for cells to become cancerous, therefore other developmental events are necessary for tumor formation.  相似文献   
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