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 The aim of the current study was to elucidate the synergism of dietary calcium restriction and exhaustive exercise in the antioxidant enzyme system of rat soleus muscle, and to investigate the involvement of neutrophils in exercise-induced muscle damage. Forty-eight male Wistar rats were assigned to the following groups: control (C) or calcium-restricted [1 month (1 M) or 3 months (3 M)]. Each group was subdivided into acutely exercised or non-exercised groups. Soleus muscle from each rat was analysed to determine the levels of antioxidant enzymes [Mn-superoxide dismutase (SOD), Cu,Zn-SOD, glutathione peroxidase (GPX), and catalase (CAT)]. Dietary calcium restriction resulted in calcium deficiency and upregulated the antioxidant enzymes examined except GPX. Conversely, exhaustive exercise significantly decreased GPX and CAT, but not SODs activities in the calcium-restricted (1 M and/or 3 M) rats. Contents of immunoreactive Mn-SOD and Cu,Zn-SOD were only increased in the 3 M rats. During calcium restriction, the mRNA expression of both forms of SOD showed initial upregulation, followed by downregulation. Exhaustive exercise significantly increased the mRNA expressions only in the 3 M rats. Moreover, exhaustive exercise markedly increased myeloperoxidase activity in soleus muscles from the 1 M and 3 M rats compared with the C rats, and significantly enhanced the ability of neutrophils to generate superoxide in the 3 M rats. The results demonstrate that dietary calcium restriction upregulates certain antioxidant enzyme activities in rat soleus muscle, indicating an enhanced resistance to potential increases in intracellular reactive oxygen species. The results also suggest that exhaustive exercise may cause oxidative damage in soleus muscle of calcium-deficient rats through the activation of neutrophils. Received: 4 August 1997 / Received after revision: 29 September 1997 / Accepted: 26 November 1997  相似文献   
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A rare case of nonfunctioning islet cell carcinoma associated with tumor thrombi in both the portal and splenic veins is reported. The patient, a 49-year-old male, had a 2-year history of occasional abdominal pain. Computed tomography (CT) disclosed a huge mass in the body of the pancreas, and celiac arteriogram showed a tumor stain in the body and tail of the pancreas. Percutaneous transhepatic portography (PTP) demonstrated an irregular filling defect, indicating intraportal tumor growth. Curative surgery, which included total pancreatectomy with combined resection (50 mm in length) and reconstruction of the portal vein, distal gastrectomy, and partial resection of the transverse colon, was performed. Histological examination of the surgical specimen led to a diagnosis of nonfunctioning islet cell carcinoma with a negative immunohistochemical stain for insulin, glucagon, somatostatin, and adrenocorticotropic hormone. The patient has been well for 38 months to date without any sign of tumor recurrence. Our experience with this case has introduced a radical resection for islet cell tumor of the pancreas, even if the tumor has extended into the portal vein.  相似文献   
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We describe a case of mucosal bile duct carcinoma with superficial spread in a 69-year-old man with gallstone pancreatitis. The patient was seen at the hospital because of abdominal pain, fever, and jaundice. Endoscopic retrograde cholangiography (ERC) demonstrated a protruding lesion in the lower third of the common bile duct (CBD) showing wall irregularity suggestive of malignancy. Percutaneous transhepatic cholangioscopy (PTCS) disclosed a papillary tumor with granular mucosa extending continuously to the middle third of the CBD. Cholangioscopic biopsy specimens taken from both the papillary tumor and surrounding granular mucosa revealed papillary adenocarcinoma. After this assessment of extent of cancer by PTCS, we performed pancreatoduodenectomy with extrahepatic bile duct resection and regional lymph node dissection. Pathology examination revealed papillary adenocarcinoma limited to the mucosal layer. The resected margin of the bile duct was free of tumor. We also reviewed 25 cases of early mucosal bile duct carcinoma described in detail in the Japanese literature, and we discuss the diagnostic advantages of PTCS.  相似文献   
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Group A rotavirus (RVA) is a major cause of acute gastroenteritis in infants and young children worldwide. This study aims to clarify the distribution of G/P types and genetic characteristics of RVAs circulating in Thailand. Between January 2014 and September 2016, 1867 stool specimens were collected from children and adults with acute gastroenteritis in six provinces in Thailand. RVAs were detected in 514/1867 (27.5%) stool specimens. G1P[8] (44.7%) was the most predominant genotype, followed by G3P[8] (33.7%), G2P[4] (11.5%), G8P[8] (7.0%), and G9P[8] (1.3%). Unusual G3P[9] (0.8%), G3P[10] (0.4%), G4P[6] (0.4%), and G10P[14] (0.2%) were also detected at low frequencies. The predominant genotype, G1P[8] (64.4%), in 2014 decreased to 6.1% in 2016. In contrast, the frequency of G3P[8] markedly increased from 5.5% in 2014 to 65.3% in 2015 and 89.8% in 2016. On polyacrylamide gel electrophoresis, most (135/140; 96.4%) of the G3P[8] strains exhibited a short RNA profile. Successful determination of the nucleotide sequences of the VP7 genes of 98 G3P[8] strains with a short RNA profile showed that they are all equine-like G3P[8] strains. On phylogenetic analysis of genome segments of two representative Thai equine-like G3P[8] strains, it was noteworthy that they possessed distinct NSP4 genes, one bovine-like and the other human-like. Thus, we found that characteristic equine-like G3P[8] strains with a short RNA electropherotype are becoming highly prevalent in children and adults in Thailand.  相似文献   
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We have studied the surgical anatomy of the intrahepatic bile duct, hepatic hilus, and caudate lobe based on intraoperative findings and selective cholangiography of surgical patients and resected specimens, and have established the cholangiographic anatomy of the intrahepatic subsegmental bile duct. Thorough knowledge of the three-dimensional anatomy of the subsegmental bile duct, hepatic hilus, and caudate lobe is indispensable for curative surgery of hilar cholangiocarcinoma. We designed and actually performed 15 kinds of hepatic segmentectomies with caudate lobectomy and extrahepatic bile buct resection in 100 consecutive patients, with curative resection being possible in 82 patients. Postoperative survival after curative resection of hilar cholangiocarcinoma was better than expected, and the 5-year survival rates for all 82 patients with curative resection and for 55 patients with curative surgery without portal vein resection were 31% and 43%, respectively. Hepatic segmentectomy with caudate lobectomy and extrahepatic bile duct resection should be designed not only in accordance with the preoperative diagnosis of tumor extension into the intrahepatic bile ducts but also so that curative surgery for advanced hilar cholangiocarcinoma can be performed.  相似文献   
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Unsuspected gallbladder carcinoma after laparoscopic cholecystectomy   总被引:5,自引:0,他引:5  
Background/Purpose Many cases have been reported of disastrous port-site recurrence after laparoscopic cholecystectomy (LC) revealed unsuspected gallbladder carcinoma (GBC). Some investigators have reported that the prognosis of patients after LC showed unsuspected GBC is not worsened by laparoscopic procedures. We retrospectively reviewed our cases and the literature to reconfirm the intrinsic risks of LC for unsuspected GBC. Methods Of 1663 patients who underwent LC from January 1991 to December 2003 in a single institution, 9 (0.54%) with unsuspected GBC were reviewed. Results These 9 patients consisted of 5 men and 4 women, whose ages ranged from 58 to 87 years, with a median age of 73 years. Two patients with a pT1a tumor (limited to mucosa) and 2 patients with a pT1b tumor (muscle layer) underwent no further operation. The remaining 5 patients with a pT2 tumor (subserosa) underwent further operations with lymph node dissection. Five patients (2 patients with pT1b and 3 patients with pT2) developed recurrence and all of them died within a median period of 19 months (range 14–37 months) after LC. The causes of death were bone metastases in 1 patient (pT2), local recurrence in 2 patients (pT1b and pT2), and peritoneal metastasis in 2 patients (one elderly patient with pT1b who underwent laparoscopic common bile duct exploration, and one patient with pT2 in whom the cystic duct was damaged during surgery). Four patients (2 with pT1 and 2 with pT2) have been doing well with a median follow-up of 39.5 months (range 12–99 months) after LC. Conclusions Surgeons should always prevent bile spillage during LC and when removing the resected gallbladder. When laparoscopic common bile duct exploration is planned, especially for elderly women, surgeons should also bear in mind the increasing possibility of unsuspected GBC.  相似文献   
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