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排序方式: 共有4317条查询结果,搜索用时 31 毫秒
91.
Tatsujiro Oka Toshiyuki Itoi Naoto Terada Hiroki Nakanishi Ryo Taguchi Kenji Hamaoka 《Circulation journal》2008,72(8):1359-1366
BACKGROUND: The effects of chronic hypoxia on cardiac membrane fatty acids and on lipid peroxidation were examined, as well as the effect of l-carnitine (LCAR), which suppresses lipid peroxidation, on this process. METHODS AND RESULTS: Four-week-old Sprague-Dawley rats were exposed to 10% oxygen for 14 days ("Hypoxia"), and then to 100% oxygen for 12 h (O2). LCAR (200 mg/kg) was administered by intraperitoneal injection daily for 2 weeks. Fatty acid composition, malondialdehyde (MDA) as a lipid peroxidation product, and antioxidants (superoxide dismutase (SOD), glutathione peroxidase and catalase) were measured. The concentration of linoleic acid was lower, and that of docosahexaenoic acid, which has more double bonds than linoleic acid, was increased in hypoxic hearts. SOD activity decreased in hypoxia, whereas MDA was unchanged, but significantly increased in "Hypoxia"+O2. LCAR reduced the increase in MDA, and had no effect on SOD activity or fatty acid composition. The administration of LCAR caused an increase in the ventricular levels of acetylcarnitine. CONCLUSIONS: These results suggest that chronic hypoxia changes the cardiac fatty acid composition of juvenile rats to fatty acids that contain more double-bonds and reduce SOD activity, and that lipid peroxidation was augmented by exposure to oxygen. 相似文献
92.
Clinical significance of the accessory pancreatic duct 总被引:4,自引:0,他引:4
Kamisawa T Egawa N Nakajima H Sakaki N Tsuruta K Okamoto A 《Hepato-gastroenterology》2003,50(54):2196-2198
BACKGROUND/AIMS: The accessory pancreatic duct is the smaller and less constant pancreatic duct in comparison with the main pancreatic duct. We investigated the patency of the accessory pancreatic duct and its role in pancreatic pathophysiology. METHODOLOGY: Dye-injection endoscopic retrograde pancreatography was performed in 411 patients. In patients in whom the main pancreatic duct could be selectively cannulated, contrast medium with indigo carmine was injected through the catheter. Excretion of the dye from the minor duodenal papilla was observed endoscopically. RESULTS: Patency of the accessory pancreatic duct was 43% of the 291 control cases. In the 46 patients with acute pancreatitis, 8 (17%) had a patent accessory pancreatic duct. The difference in patency between this group and the normal group was significant (p < 0.01). Especially, patency of the accessory pancreatic duct was only 8% of the 13 patients with acute biliary pancreatitis. In the patients with pancreaticobiliary maljunction, biliary carcinoma occurred in 72% of patients with a nonpatent accessory pancreatic duct, but in contrast, it occurred only in 30% of those with a patent accessory pancreatic duct. This difference was significant (p < 0.05). Lower amylase level in the bile of patients with pancreaticobiliary maljunction with a patent accessory pancreatic duct was frequently observed than those with a nonpatent accessory pancreatic duct. CONCLUSIONS: A patent accessory pancreatic duct may prevent acute pancreatitis by lowering the pressure in the main pancreatic duct. In cases of pancreaticobiliary maljunction with a patent accessory pancreatic duct, the incidence of carcinogenesis of the bile duct might be lower, as the reflux of the pancreatic juice to the bile duct might be reduced by the flow of the pancreatic juice into the duodenum through the accessory pancreatic duct. 相似文献
93.
Mongan NP Jääskeläinen J Green K Schwabe JW Shimura N Dattani M Hughes IA 《The Journal of clinical endocrinology and metabolism》2002,87(3):1057-1061
The androgen insensitivity syndrome (AIS) is the most common cause of male undermasculinization and is typically caused by mutations in the AR gene. Affected individuals may exhibit either complete external feminization (complete AIS) or a partial phenotype (partial AIS). Here we describe monozygotic twins diagnosed with complete AIS who each possess two substitutions (C-->G at position 2930 and T-->C at position 2955, both in exon 7), leading to Phe(856)Leu and Ser(865)Pro mutations, respectively. Neither parent was found to be a carrier for these mutations, indicating that the double mutation arose de novo. Both mutations were recreated by site-directed mutagenesis and compared functionally with the wild-type receptor. The Phe(856)Leu mutation did not affect androgen binding when expressed in COS-1 cells, nor did this mutation decrease androgen-dependent trans-activation in transfected HeLa cells. However, the Ser(865)Pro mutation completely ablated androgen binding and trans-activation. In this study we demonstrate that the replacement of serine by proline at position 865 is sufficient in itself to cause complete AIS in these twins. Analyses of nuclear receptor structures suggest that this mutation is likely to perturb the conformation of helix 10/11, which plays a role in ligand binding, dimerization, and receptor activation. To our knowledge this is the first confirmed instance of AIS (complete or partial) due to an AR mutation occurring in twins. Furthermore, the phenotype was associated with two mutations that were both novel in nature. 相似文献
94.
95.
Shigeo Koido Toshifumi Ohkusa Kosaburo Nakae Tetsuji Yokoyama Tomoyoshi Shibuya Naoto Sakamoto Kan Uchiyama Hiroshi Arakawa Taro Osada Akihito Nagahara Sumio Watanabe Hisao Tajiri 《World journal of gastroenterology : WJG》2014,20(22):6961-6967
AIM:To evaluate significant risk factors for incomplete colonoscopy at a Japanese academic hospital.METHODS:A total of 11812 consecutive Japanese people were identified who underwent a colonoscopy at an academic hospital.A multiple logistic regression model was used to evaluate retrospectively the significant risk factors for incomplete colonoscopy.RESULTS:The cecal intubation rate was 95.0%.By univariate analysis,age,female sex,poor bowel cleansing,and a history of abdominal or pelvic surgery were significant risk factors for incomplete colonoscopy(P<0.001).Moreover,age-and sex-adjusted analysis showed that significant risk factors for incomplete colonoscopy were female sex(OR=1.38,95%CI:1.17-1.64,P=0.0002),age≥60 years old(OR=1.44,95%CI:1.22-1.71,P<0.0001),a history of prior abdominal or pelvic surgery(OR=1.55,95%CI:1.28-1.86,P<0.0001),poor bowel cleansing(OR=4.64,95%CI:3.69-5.84,P<0.0001),and inflammatory bowel disease(IBD)(OR=1.48,95%CI:1.13-1.95,P=0.0048).In Japanese men,by age-adjusted analysis,IBD(OR=1.69,95%CI:1.18-2.43,P=0.005)was an independent risk factor for incomplete colonoscopy.CONCLUSION:Several characteristics in the Japanese population were identified that could predict technical difficulty with colonoscopy. 相似文献
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98.
Arief Rahadian Daiju Fukuda Hotimah Masdan Salim Shusuke Yagi Kenya Kusunose Hirotsugu Yamada Takeshi Soeki Masataka Sata 《Journal of atherosclerosis and thrombosis》2020,27(11):1141
Aim: Recent studies have demonstrated that selective sodium–glucose cotransporter 2 inhibitors (SGLT2is) reduce cardiovascular events, although their mechanism remains obscure. We examined the effect of canagliflozin, an SGLT2i, on atherogenesis and investigated its underlying mechanism.Method: Canagliflozin (30 mg/kg/day) was administered by gavage to streptozotocin-induced diabetic apolipoprotein E-deficient (ApoE−/−) mice. Sudan IV staining was performed at the aortic arch. Immunostaining, quantitative RT-PCR, and vascular reactivity assay were performed using the aorta. In vitro experiments using human umbilical vein endothelial cells (HUVECs) were also performed.Result: Canagliflozin decreased blood glucose (P < 0.001) and total cholesterol (P < 0.05) levels. Sudan IV staining showed that 12-week canagliflozin treatment decreased atherosclerotic lesions (P < 0.05). Further, 8-week canagliflozin treatment ameliorated endothelial dysfunction, as determined by acetylcholine-induced vasodilation (P < 0.05), and significantly reduced the expressions of inflammatory molecules such as ICAM-1 and VCAM-1 in the aorta at the RNA and protein levels. Canagliflozin also reduced the expressions of NADPH oxidase subunits such as NOX2 and p22phox in the aorta and reduced urinary excretion of 8-OHdG, suggesting a reduction in oxidative stress. Methylglyoxal, a precursor of advanced glycation end products, increased the expressions of ICAM-1 and p22phox in HUVECs (P < 0.05, both). Methylglyoxal also decreased the phosphorylation of eNOSSer1177 and Akt but increased the phosphorylation of eNOSThr495 and p38 MAPK in HUVECs.Conclusion: Canagliflozin prevents endothelial dysfunction and atherogenesis in diabetic ApoE−/− mice. Anti-inflammatory and antioxidative potential due to reduced glucose toxicity to endothelial cells might be its underlying mechanisms. 相似文献
99.
Yoshiyuki Abe Ken Yamaji Yukari Endo Makio Kusaoi Soichiro Nakano Kwang‐Seok Yang Kurisu Tada Hiroshi Tsuda Naoto Tamura 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2020,24(2):208-214
Diffuse alveolar hemorrhage (DAH) is well known as a serious complication of microscopic polyangiitis (MPA). We examined the effectiveness of plasma exchange (PLEX) therapy to reduce mortality in Japanese DAH patients with MPA. This retrospective, double‐center, observational cohort study included 20 DAH patients with MPA who were admitted to Juntendo University Hospital or Juntendo Koto Geriatric Medical Center between April 1998 and March 2018. The primary outcome was non–disease‐specific mortality. The 1‐year survival rate of patients with PLEX therapy (N = 4) was higher than that of patients with conventional therapy (N = 16, 75% and 13%, respectively, P = 0.037). Higher values of the 1996 Five‐Factor Score (FFS) and 2009 FFS were associated with increased mortality, with hazard ratios of 2.29 (P = 0.040) and 2.41 (P = 0.043), respectively, by Cox univariate analysis. We investigated PLEX therapy for reducing mortality in DAH patients with MPA, and the 1996 FFS and 2009 FFS were both independent prognostic factors. 相似文献
100.