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101.
With increasing expectations for carbon neutrality, dry reforming is anticipated for direct conversion of methane and carbon dioxide: the main components of biogas. We have found that dry reforming of methane in an electric field using a Pt/CeO2 catalyst proceeds with sufficient rapidity even at a low temperature of about 473 K. The effect of the electric field (EF) on dry reforming was investigated using kinetic analysis, in situ DRIFTs, XPS, and DFT calculation. In situ DRIFTs and XPS measurements indicated that the amount of carbonate, which is an adsorbed species of CO2, increased with the application of EF. XPS measurements also confirmed the reduction of CeO2 by the reaction of surface oxygen and CH4. The reaction between CH4 molecules and surface oxygen was promoted at the interface between Pt and CeO2.

In the dry reforming of methane in an electric field, the reaction between CH4 molecules and surface oxygen was promoted at the interface between Pt and CeO2.  相似文献   
102.
A 58-year-old Japanese man was brought to the emergency room due to disturbance of consciousness. He regained consciousness on the day of admission and started taking hospital meals, but he needed intravenous glucose administration for eight days. The total amount of glucose administration was 4,464 g. It took over three weeks for exogenous insulin to be almost undetectable. While degludec binds to albumin and exerts glucose-lowering effects for a long time, the above-mentioned period of three weeks was consistent with the half-life of albumin. Hypoglycemia induced by massive dose of insulin degludec is persistent and prominent.  相似文献   
103.
104.
BACKGROUND & AIMS: We investigated the effects of macrophage migration inhibitory factor (MIF) antibodies in experimental colitis-induced dextran sulfate sodium (DSS) and trinitrobenzenesulfonic acid (TNBS) and examined whether plasma levels of MIF were elevated in patients with inflammatory bowel disease (IBD). METHODS: BALB/c or C57BL/6 mice were fed 4% DSS in their drinking water for up to 7 days with and without administration of an anti-MIF antibody every 2 days. The severity of inflammation in the cecum and colon was assessed by clinical signs and histologic scoring. Tissue levels of MIF, tumor necrosis factor (TNF)-alpha, interferon gamma (IFN-gamma), interleukin (IL)-4, and matrix metalloproteinase (MMP)-13 messenger RNA (mRNA) were measured. The effects of anti-MIF antibody on chronic colitis induced by TNBS was assessed in BALB/c mice. Plasma MIF concentrations were assayed in patients with Crohn's disease, ulcerative colitis, and healthy controls. RESULTS: During DSS-induced colitis, colonic MIF mRNA expression was increased. Clinical signs and histopathologic features were significantly improved in animals given anti-MIF antibody. DSS-induced up-regulation of colonic TNF-alpha and IFN-gamma were significantly suppressed in animals given the anti-MIF antibody. Colonic IL-4 was decreased during DSS but restored to baseline by the anti-MIF antibody. The anti-MIF antibody prevented MMP-13 up-regulation by DSS and ameliorated TNBS colitis. Plasma MIF was elevated in patients with Crohn's disease or ulcerative colitis compared with healthy controls. CONCLUSIONS: We conclude that anti-MIF antibodies reduce the severity of experimental colitis and limit the up-regulation of Th1-type cytokines. Anti-MIF antibodies are of potential therapeutic use in IBD.  相似文献   
105.
Degradation of p57Kip2 mediated by SCFSkp2-dependent ubiquitylation   总被引:19,自引:0,他引:19       下载免费PDF全文
The abundance of the cyclin-dependent kinase (CDK) inhibitor p57Kip2, an important regulator of cell cycle progression, is thought to be controlled by the ubiquitin-proteasome pathway. The Skp1/Cul1/F-box (SCF)-type E3 ubiquitin ligase complex SCFSkp2 has now been shown to be responsible for regulating the cellular level of p57Kip2 by targeting it for ubiquitylation and proteolysis. The elimination of p57Kip2 was impaired in Skp2-/- cells, resulting in abnormal accumulation of the protein. Coimmunoprecipitation analysis also revealed that Skp2 interacts with p57Kip2 in vivo. Overexpression of WT Skp2 promoted degradation of p57Kip2, whereas expression of a dominant negative mutant of Skp2 prolonged the half-life of p57Kip2. Mutation of the threonine residue (Thr-310) of human p57Kip2 that is conserved between the COOH-terminal QT domains of p57Kip2 and p27Kip1 prevented the effect of Skp2 on the stability of p57Kip2, suggesting that phosphorylation at this site is required for SCFSkp2-mediated ubiquitylation. Finally, the purified recombinant SCFSkp2 complex mediated p57Kip2 ubiquitylation in vitro in a manner dependent on the presence of the cyclin E-CDK2 complex. These observations thus demonstrate that the SCFSkp2 complex plays an important role in cell-cycle progression by determining the abundance of p57Kip2 and that of the related CDK inhibitor p27Kip1.  相似文献   
106.

Background  

Little is understood about worldwide changes in the epidemiological distribution of the etiology of liver cirrhosis (LC). The present study examines the etiology of liver cirrhosis in Japan using a nationwide survey.  相似文献   
107.
The study group of the Japanese Society of Gastroenterology released evidence-based clinical practice guidelines for chronic constipation (CC) in 2017, and irritable bowel syndrome (IBS) was treated as one of the causes of CC. We examined the differences in characteristics between IBS and non-IBS subjects with CC who underwent a medical check-up in Japan. A total of 10,658 subjects participated in this study, and we focused on 467 subjects who fulfilled the diagnostic criteria of CC using a questionnaire survey. The number of IBS subjects was 21, and they had sleep disorders, were more symptomatic (e.g., abdominal pain, abdominal bloating/distension, feeling stressed, annoyance, lack of motivation, fatigue upon waking, and feeling depressed), and had more episodes of sensation of incomplete evacuation and anorectal obstruction/blockage during defecation than non-IBS subjects. Furthermore, stool frequency of IBS subjects was significantly different from non-IBS subjects. Multivariate ordinal logistic regression analysis revealed that the factors associated with a higher stool frequency were IBS [odds ratio (OR), 2.46; 95% confidence interval (CI), 1.00–6.05; p = 0.049], male sex (OR, 1.97; 95% CI, 1.20–3.23; p = 0.007), and regular exercise (OR, 1.80; 95% CI, 1.05–3.07; p = 0.033). These findings suggest that IBS has unique characteristics in subjects with CC.  相似文献   
108.
Mediastinal hemangiopericytoma (HPC) was diagnosed in a 3‐year‐old female. The incidence of this tumor is rare in children, and few data are available to guide clinical management. The surgical resection was incomplete and she received adjuvant radiation therapy and chemotherapy. The patient is alive without adverse events 6 years after diagnosis. Pediatr Blood Cancer 2009;53:206–207. © 2009 Wiley‐Liss, Inc.  相似文献   
109.
Of all distant metastases from carcinoma of the papilla of Vater (CPV), the liver is the most frequent site (more than 60%) and should be specifically targeted in the effort to improve the prognosis. However, the optimal chemotherapy regimen for nonresectable liver metastasis has not been clearly established. In this preliminary report, we note a patient with multiple hepatic metastases from CPV successfully treated using intrahepatic infusion of 5-fluorouracil (FU) with low-dose cisplatin. A 62-year-old woman underwent curative pylorus-preserving pancreaticoduodenectomy for CPV. Four months after surgery, followup computed tomography (CT) demonstrated multiple liver metastases. Weekly intrahepatic arterial infusion chemotherapy of 5-FU, 350 mg/m2, with low-dose cisplatin (7 mg/m2) was started. Ten months after starting chemotherapy, a complete response was obtained. To date, the patient continues to receive this weekly hepatic arterial infusion chemotherapy without any side effects, and she has successfully maintained a long-term complete response for 20 months. The patient remains well and was able to proceed with daily activity at the last follow up 30 months after starting this chemotherapy regimen. This regimen is safe and effective and is recommended as one of the treatment choices for liver metastases from CPV.  相似文献   
110.
To estimate the relationship between the visceral adipose tissue (AT) area and cancer cachexia, 13 cachectic patients (7 males, 6 females; age 65.2 ± 11.0 years; body mass index 20.8 ± 4.1 kg/m2) were examined by computed tomography (CT) scanning. Cachectic cancer patients who had a 10% decrease of body weight and died within 6 months because of gastrointestinal carcinoma had a significantly smaller visceral AT area than control subjects (mean ± sd: 43.9 ± 42.2 cm2 vs. 93.4 ± 56.0 cm2, P < 0.05, P=0.014). Otherwise, there were no significant differences between the visceral AT areas of cachectic cancer patients and those of cancer patients with resectable tumors treated by curative operation (mean ± sd: 68.8 ± 57.7 cm2) (NS, P=0.206). There was, however, a tendency for cachectic cancer patients to have a smaller visceral AT area than those with resectable tumors. This result suggests that the visceral AT area is not preserved in the cachectic state associated with cancer. © 1994 Wiley-Liss, Inc.  相似文献   
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