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951.
An 82-year-old woman was referred to our hospital because of hypoalbuminemia and generalized edema. Hypercortisolemia was subsequently found as the levels of serum cortisol and plasma adrenocorticotropic hormone (ACTH) sampled in a fasting morning were 140 pg/mL and 41.9 μg/dL, respectively. These hormones were not suppressed after taking low-dose dexamethasone the previous night and increased to a mild extent in response to administration of corticotrophin-releasing hormone, suggesting presence of pituitary adenoma producing ACTH (Cushing's disease). However, intrasella localization of pituitary adenoma could not be determined by magnetic resonance imaging. Soon after administration of metyrapone was started in an attempt to reduce her cortisol levels, the patient suffered from severe pneumonia. The pulmonary infection and peripheral edema were improved with decreases in cortisol levels by continuing metyrapone administration with antibiotics and finally she was discharged from the hospital on foot. Metyrapone is a useful therapeutic choice to achieve a remission of cortisol levels in the elderly patients with Cushing's disease in association with serious hypercortisolemia impending severe infection.  相似文献   
952.
目的 利用短期口服小剂量双氯芬酸建立大鼠非甾体类抗炎药(NSAID)小肠黏膜损伤模型,观察甲硝唑、雷贝拉唑对NSAID所致小肠黏膜损伤的预防作用.方法 将64只大鼠随机抽签分为空白组、模型组、甲硝唑组和雷贝拉唑组,每组16只.再将各组动物进一步分为T1(急性期)和T2(亚急性期)亚组,每组8只.甲硝唑组和雷贝拉唑组大鼠在造模前1 d分别给予甲硝唑50 mg/kg或雷贝拉唑15 mg/kg灌胃1次.次日,空白组以1 ml蒸馏水灌胃每天2次;模型组给予双氯芬酸7.5 mg/kg每天2次;甲硝唑组给予双氯芬酸7.5 mg/kg和甲硝唑50 mg/kg,每天2次;雷贝拉唑组给予双氯芬酸7.5 mg/kg和雷贝拉唑15 mg/kg,每天2次.各组的T1亚组灌胃1 d后处死,T2亚组灌胃5 d后处死.结果 小剂量双氯芬酸能引起小肠黏膜显著出血性损伤,小肠黏膜可见大量红斑、糜烂、溃疡,局部肠腔可见囊样扩张.模型组的T1、T2亚组损伤均较空白组严重(P<0.05),且T2组损伤明显大于T1组(P<0.05).甲硝唑和雷贝拉唑组的T1,T2亚组的损伤均小于模型组(均P<0.05).模型组T1亚组的血清一氧化氮含量明显低于空白组(P<0.05),T2亚组则明显高于空白组(P<0.05).模型组与甲硝唑组、雷贝拉唑组之间一氧化氮含量比较差异无统计学意义(P>0.05).结论 短期小剂量口服双氯芬酸后,即可引起小肠黏膜损伤.并随时间呈进行性加重; 血清一氧化氮含量在小肠黏膜损伤后呈现先降低,后升高趋势.甲硝唑、雷贝拉唑对NSAID诱发的小肠黏膜损伤具有一定的预防作用.  相似文献   
953.
954.
Background: Upregulation of matrix metalloproteinase‐9 (MMP‐9) induced by tumour necrosis factor‐α (TNF‐α) is reportedly involved in a variety of non‐neoplastic and neoplastic diseases. In this study, we examined which signalling pathways are involved in TNF‐α‐induced MMP‐9 upregulation in cholangiocarcinoma (CC). Methods: We used two CC cell lines: HuCCT‐1 and CCKS‐1. Results: In an ex vivo study using HuCCT‐1 and CCKS‐1 cells, TNF‐α treatment induced MMP‐9 production and activation via interaction with TNF receptor‐1 (TNF‐R1) but not with TNF receptor‐2 (TNF‐R2), shown by zymography, and increased MMP‐9 promoter activity (luciferase assay). As for the signalling pathway, TNF‐α stimulation led to the phosphorylation of extracellular signal‐regulated kinase 1/2 (Erk1/2) and p38 mitogen‐activated protein kinase (p38MAPK) and translocation of nuclear factor κB (NF‐κB) (p65) into the nuclei. Inhibition studies using SB203580 (inhibitor of p38MAPK), U0126 (inhibitor of mitogen‐activated or extracellular signal‐regulated protein kinase 1/2) and MG132 (inhibitor of NF‐κB) showed that the phosphorylation of Erk1/2 and p38MAPK with activation of NF‐κB was closely related to MMP‐9 upregulation in both cell lines. Conclusion: These data suggest that TNF‐α/TNF‐R1 interaction leads to the phosphorylation of Erk1/2 and p38MAPK and nuclear translocation of NF‐κB, which is closely associated with the production and activation of MMP‐9 in cultured CC cells of HuCTT‐1 and CCKS‐1. Upregulation of MMP‐9 with NF‐κB activation may be involved in the tumour invasion of CC.  相似文献   
955.
Perineural invasion in pancreatic cancer.   总被引:37,自引:0,他引:37  
INTRODUCTION: Perineural invasion is regarded as a factor associated with local recurrence of pancreatic cancer. AIM: To examine perineural invasion of pancreatic cancer pathologically and clinically. METHODOLOGY: In 24 cases of surgically resected pancreatic cancer, correlations among the degree of perineural invasion, differentiation, interstitial connective tissue, lymph node metastasis, and survival rate were examined. Consecutive 5-microm serial sections (n = 1072) were made in six cases that showed characteristic mode of perineural invasion. RESULTS: Perineural invasion was observed in 17 cases (70.8%; ne0-7; ne1-6; ne2-9; and ne3-2 cases). Perineural invasion was absent in three of five cases of papillary carcinoma, but was observed in 12 of 14 cases of moderately differentiated carcinoma. The survival rate for ne0 was better than that of the other groups, with the 3-year survival rate being 57.1%. Perineural cancer glands had developed discontinuously in two cases. CONCLUSIONS: Perineural invasion is an important prognostic factor in pancreatic cancer, increasing as the cancer becomes undifferentiated. Even if there are no cancer cells at the margin of the pancreas at the time of surgery, the cancer cells may spread further to the noncancerous pancreas or retroperitoneum. Sufficient dissection of the neural plexus or intraoperative radiation may be required.  相似文献   
956.
Radical resection for pancreatic cancer   总被引:10,自引:0,他引:10  
Ductal adenocarcinoma of the pancreas is still characterized by (1) poor prognosis after surgery and (2) extreme difficulty in early diagnosis, and we need a breakthrough. For the first problem, we have performed a wide range of lymphatic and connective tissue clearance (extended pancreatectomy) which has succeeded in improving the 5-year survival rate from 8% to 24% via decreasing the incidence of locoregional recurrence. When liver perfusion chemotherapy via the hepatic artery and the portal vein was added to the patients who had received extended pancreatectomy, the 5-year survival rate was further elevated to 40% via decreasing the incidence of hepatic metastasis. We conclude that pancreatic cancer should be treated by the better-balanced treatments between locoregional control and prevention of hepatic metastasis. For the second problem, we have more actively collected pancreatic juice to perform cytodiagnosis even though no obvious tumor was delineated by the conventional imaging diagnoses. When cancer cells were detected in the pancreatic juice, our method of intraoperative cytology was very useful in precisely locating the occult lesion indicating an appropriate range of pancreatectomy. The resected pancreas was proven to have included borderline malignancy and in situ or minimally-invasive carcinoma by the postoperative histology, and disease-free 5-year survival rate was 100%. In the future, we need to detect patients with a high risk of pancreatic cancer and develop a less-painful method to collect the pancreatic juice.  相似文献   
957.
Recent research progress indicates a close link between ghrelin, a natural ligand of GH secretagogues receptor (GHS-R), and both the metabolic balance and body composition. To clarify the involvement of ghrelin and GHS-R in the process of adipogenesis, we measured the expression of GHS-R and peroxisome proliferator-activated receptor gamma 2 (PPAR-gamma 2) mRNA in rat adipocytes using semiquantitative RT-PCR methods. The levels of GHS-R mRNA increased by up to 4-fold in adipose tissue from epididymal and parametrial regions as the rat aged from 4-20 wk and were significantly elevated during the differentiation of preadipocytes in vitro. Ghrelin (10(-8) M for 10 d) stimulated the activity of glycerol-3-phosphate dehydrogenase and the differentiation of rat preadipocytes in vitro. Ghrelin treatment also significantly increased the levels of PPAR-gamma 2 mRNA in primary cultured rat differentiated adipocytes. In addition, isoproterenol (10(-8) M, 40 min)-stimulated lipolysis was significantly reduced by simultaneous ghrelin treatment in a dose-dependent manner in vitro. In conclusion, the expression of GHS-R in rat adipocytes increases with the age and during adipogenesis. Ghrelin in vitro stimulates the differentiation of preadipocytes and antagonizes lipolysis. Ghrelin may therefore play an important role in the process of adipogenesis in rats.  相似文献   
958.
OBJECTIVE: Coupling factor 6 is an endogenous inhibitor of prostacyclin synthesis and might function as an endogenous vasoconstrictor in the fashion of a circulating hormone in rats. We investigated the role of coupling factor 6 in human hypertension. METHODS AND RESULTS: The patients with essential hypertension (EH) (n = 30) received a series of normal salt diet (12 g salt/day) for 3 days, low salt diet (2 g salt/day) for 7 days, and high salt diet (20-23 g salt/day) for 7 days. Normotensive control subjects (n = 27) received normal and low salt diets. The plasma level of coupling factor 6, measured by radioimmunoassay, during normal salt diet was higher in patients with EH than in normotensive subjects (17.6 +/- 1.7 versus 12.8 +/- 0.5 ng/ml, P < 0.01). Whereas the plasma level of coupling factor 6 was unchanged after salt restriction in normotensive subjects, it was decreased after salt restriction (from 12 g/day to 2 g/day) and was increased after salt loading (from 2 g/day to 20-23 g/day) in patients with EH. This increase in plasma level of coupling factor 6 was abolished by oral administration of ascorbic acid, but the level of blood pressure was unaffected. The percentage changes in plasma coupling factor 6 level after salt restriction and loading were positively correlated with those in mean blood pressure (r = 0.57, P < 0.01), and negatively correlated with those in plasma nitric oxide level (r = -0.51, P < 0.05). CONCLUSION: These indicate that circulating coupling factor 6 is elevated in human hypertension and modulated by salt intake presumably via reactive oxygen species.  相似文献   
959.
Background: It has been unclear whether psychological distress and prevalence of metabolic syndrome (MS) is associated independent of cardiorespiratory fitness and/or visceral fat area in patients with type 2 diabetes mellitus (type 2 DM). Methods: Ninety-seven newly diagnosed Japanese men with type 2 DM (aged 26-81) who did not receive any intervention or pharmacological therapy were divided into two groups of highly distressed (HD) and less distressed (LD) by the cutoff point of the General Health Questionnaire (GHQ). In addition, cardiorespiratory fitness (estimated oxygen uptake: [Formula: see text] O(2)max), visceral fat area (VFA), glucose and lipid metabolism, and resting blood pressure were assessed. MS was defined based on the criteria proposed by the World Health Organization (WHO). The odds-ratios (OR) for the frequency of a low level of fitness, extremely accumulated VFA, metabolic abnormalities, and MS in both groups were calculated using a logistic regression model. Results: The OR for the frequency of a low level of fitness, the top quartile of VFA, hyperinsulinemia, and MS were significantly higher in the HD than in the LD. The significantly high OR of hyperinsulinemia and MS in the HD disappeared after adjusting for [Formula: see text] O(2)max and/or VFA. Conclusions: Our study suggests that the association of psychological distress with hyperinsulinemia and MS might depend on cardiorespiratory fitness and/or VFA in Japanese men with type 2 DM.  相似文献   
960.
BACKGROUND/AIM: Trefoil factor family (TFF)1,2,3 are involved in a homeostasis/repair process of mucosal epithelia. In this study, the significance of TFF family and deleted in the malignant brain tumor-1 (DMBT1), a putative receptor of TFF2, in the intrahepatic biliary tree was investigated in normal and diseased livers. MATERIALS AND METHODS: Expression of TFF1,2,3 and DMBT1 were examined immunohistochemically in primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), chronic viral hepatitis (CVH), extrahepatic biliary obstruction (EBO), and normal livers. RESULTS: In normal livers, TFF1,3 and DMBT1 were infrequently detectable in large and rarely in small bile ducts, respectively. TFF2 was not detectable in large bile ducts. In large bile duct diseases (PSC and EBO), expression of TFF3 and DMBT1 were increased. In small bile duct diseases (PBC and CVH), expression of TFF2/DMBT1 was induced in moderately to severely damaged ducts irrespective of etiology. CONCLUSION: The intrahepatic biliary tree shows a site-characteristic expression and induction of TFF1,2,3 and DMBT1. In large bile ducts, TFF1,3 were constitutively expressed and increased in pathologic bile ducts. In small bile ducts, TFF2/DMBT1 is induced in damaged ducts irrespective of etiologies. However, the cytoprotective/repair property of TFF2/DMBT1 may not be enough to prevent the following bile duct loss in PBC.  相似文献   
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