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41.
Chang Mo Li Fumiko Kimura Yasushi Endo Chizuko Maruyama Kenshiro Fujimoto 《European Journal of Lipid Science and Technology》2005,107(3):173-179
The stabilities of a commercial diacylglycerol‐rich oil (DAG) and a salad oil (TAG) that had been prepared from a mixture of rapeseed and soybean oils were compared while frying potatoes at 180 °C for 3 h. The representative chemical and physical characteristics of the oils were assessed before and after frying, together with the amount of volatile aldehydes in the exhaust of frying. Among the deterioration indications, the carbonyl value, polymer content, and residual polyunsaturated fatty acid content were similar and not significantly different between the TAG and DAG. On the other hand, the characteristics relating to free fatty acids, i.e. the acid value and emission of chemiluminescence at 100 °C, were greater and the smoke and flash points were lower in the DAG than in the TAG. An irritating odor was generated from the DAG after 1 h of frying and got stronger as frying continued. These results suggested that DAG more easily forms free fatty acids under frying conditions than TAG. 相似文献
42.
In this study, both naturally occurring and artificial amino acids were successfully transformed into the corresponding urethane derivatives using diphenyl carbonate. The urethanes thus prepared could be efficiently cyclized into amino acid N‐carboxyanhydrides (NCAs) without the requirement of phosgene. In addition, the presence of primary amines converted the urethane derivatives into NCAs and initiated the ring‐opening polymerization of the in situ formed NCAs, allowing for the well‐defined synthesis of polypeptides. These polypeptides contained initiating ends functionalized by an amine‐derived residue and propagating ends bearing the reactive amino group. By precise control of the structures of the polypeptides, various polypeptide conjugates such as block copolymers and graft copolymers were successfully synthesized as designed, and their applications in antifouling coatings against proteins, drug delivery systems and biosensors were demonstrated. © 2019 Society of Chemical Industry 相似文献
43.
Izabela Wysocka Agata Markowska‐Szczupak Piotr Szweda Jacek Ryl Maya Endo‐Kimura Ewa Kowalska Grzegorz Nowaczyk Anna Zieliska‐Jurek 《Indoor air》2019,29(6):979-992
The photocatalytic deactivation of volatile organic compounds and mold fungi using TiO2 modified with mono‐ and bimetallic (Pt, Cu, Ag) particles is reported in this study. The mono‐ and bimetal‐modified (Pt, Cu, Ag) titanium(IV) oxide photocatalysts were prepared by chemical reduction method and characterized using XRD, XPS, DR/UV‐Vis, BET, and TEM analysis. The effect of incident light, type and content of mono‐ and bimetallic nanoparticles deposited on titanium(IV) oxide was studied. Photocatalytic activity of as‐prepared nanocomposites was examined in the gas phase using LEDs array. High photocatalytic activity of Ag/Pt‐TiO2 and Cu/Pt‐TiO2 in the reaction of toluene degradation resulted from improved efficiency of interfacial charge transfer process, which was consistent with the fluorescence quenching effect revealed by photoluminescence (PL) emission spectra. The photocatalytic deactivation of Penicillium chrysogenum, a pathogenic fungi present in the indoor environment, especially in a damp or water‐damaged building using mono‐ and bimetal‐modified (Pt, Cu, Ag) titanium(IV) oxide was evaluated for the first time. TiO2 modified with mono‐ and bimetallic NPs of Ag/Pt, Cu, and Ag deposited on TiO2 exhibited improved fungicidal activity under LEDs illumination than pure TiO2. 相似文献
44.
45.
Saito M Kozutsumi D Kawasaki M Kanbashi M Nakamura R Sato Y Endo M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(3):228-238
A simple, sensitive and selective method with gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed to detect 342 pesticides and veterinary drugs contaminating bovine milk at the maximum residue limits (MRLs) defined in the "positive list system". Sample preparation was performed by extracting the analytes with acetonitrile, followed by salting-out with sodium chloride. For some pesticides, the extract was further cleaned up by n-hexane partitioning and PSA cartridge column chromatography. GC/MS-EI or -NCI was used to determine pesticide residues, while LC/MS/MS-ESI was applicable to the determination of pesticide and veterinary drug residues. The variation of the recoveries of these drugs at MRL was relatively wide; however the relative standard deviations of the recovery of each drug were within 28%, suggesting that the present method is good enough for use as a screening test for contaminants at the MRLs. These results show that this method is useful for multiresidue analysis of numerous pesticides and veterinary drugs in bovine milk. 相似文献
46.
Compound-specific factors influencing sorption nonlinearity in natural organic matter 总被引:2,自引:0,他引:2
Endo S Grathwohl P Haderlein SB Schmidt TC 《Environmental science & technology》2008,42(16):5897-5903
Nonlinear sorption by natural organic matter may have a significant impact on the behavior of organic contaminants in soils and sediments. This study presents a molecular probe approach based on linear solvation energy relationships (LSERs) to identify and quantify the molecular interactions causing concentration-dependent sorption and proposes estimation methods for sorption nonlinearities. Sorption isotherms ranging over concentrations of more than 4 orders of magnitude were determined in batch systems for 23 and 16 chemically diverse probe compounds in a lignite sample and a peat soil, respectively. Each sorbent showed characteristic nonlinear sorption with Freundlich exponents (1/n) being 0.7-1. The LSER-based analysis revealed that the strength of nonspecific interactions did not vary with concentration for both sorbents. In lignite, specific interactions did not affect sorption nonlinearity either, suggesting that compound-independent factors of lignite were responsible for the nonlinear sorption. In the peat soil, by contrast, the specific interactions related to the solute polarizability/dipolarity parameter (S) decreased with increasing concentration. Consequently, compounds of higher S values were more susceptible to nonlinear sorption in the peat soil. Phenol probes have shown that hydrogen bond donating properties of sorbate compounds have a substantial impact on the overall strength of sorption with organic matter, but no significant influence on sorption nonlinearity. Heterocyclic aromatic compounds appear to undergo additional interactions that are not accounted for by the LSER. These additional interactions considerably enhance both sorption capacity and nonlinearity. 相似文献
47.
T Takeshita T Arita H Asao N Tanaka M Higuchi H Kuroda K Kaneko H Munakata Y Endo T Fujita K Sugamura 《Canadian Metallurgical Quarterly》1996,225(3):1035-1039
We molecularly cloned a cDNA coding for a novel phosphotyrosine molecule with a 70 kDa molecular mass, named STAM (signal transducing adaptor molecule), which is tyrosine-phosphorylated rapidly after stimulation with various cytokines such as IL-2, IL-3, IL-4, IL-7, GM-CSF, EGF and PDGF. STAM contains an SH3 (Src-homology 3) domain and the ITAM (immunoreceptor tyrosine-based activation motif), suggesting that STAM acts as an adaptor molecule involved in signal transducing pathways from the cytokine receptors. 相似文献
48.
K Endo 《Canadian Metallurgical Quarterly》1995,14(2):185-198
Human plasma fibronectin (pFN), an adhesive protein, was covalently immobilized onto an alkylaminosilane derivative of a NiTi substrate with glutaraldehyde through Schiff's base formation. The surface at different stages of the modification was characterized by X-ray photoelectron spectroscopy (XPS), and the amount of immobilized pFN was determined by a fluorometric method. The spreading behavior of human gingival fibroblasts was examined on the modified surface. The XPS spectra suggested that gamma-aminopropyltriethoxysilane (gamma-APS) was bonded to the surface through metallosiloxane bonds (Ti-O-Si) formed via a condensation reaction between the silanol end of gamma-APS and the surface hydroxyl group, with a highly cross-linked siloxane network formed after heat treatment of the silanized surface at 100 degrees C. The pFN was immobilized at the surface density of 1.1 micrograms.cm-2, and significantly promoted fibroblast spreading, suggesting that this chemical modification offers an effective means of controlling metal/cell interactions. These results may contribute to the development of bioactive metallic implants. 相似文献
49.
H Takahashi M Sagawa M Sato A Sakurada C Endo M Minowa S Sugawara Y Saito S Fujimura 《Canadian Metallurgical Quarterly》1998,36(10):857-863
Cystic neoplasms of the pancreas constitute about 9% of all cystic lesions of the pancreas and less than 1% of all pancreatic neoplasms. The case of a 70 years-old woman with microcystic cystadenoma is reported. CT-scan of the abdomen diagnosed a 5 cm multilocular septated cyst, with calcifications in the context, localized in the head-uncinate process of the pancreas. The mass was well separated by a sharp cleavage plane with portal vein and superior mesenteric vessels. An ERCP showed cephalic symmetrical stenosis (diameter 3 mm) of the main pancreatic duct (MPD), mildly dilated in the remaining tract (diameter 6 mm). An intraoperative biopsy of the cystic wall was performed. Therefore, it was decided to proceed with a duodenum-preserving resection of the head of the pancreas (DPPHR), including the stenosis tract of the MPD in the surgical specimen. The reconstructive procedure consisted, by i.v. jejunal loop transposition, in a side-to-side pancreatico-jejunostomy, including in the anastomosis both corpocaudal stump and the resection cavity of the pancreatic head, and an end-to-side Roux-en-Y jejuno-jejunostomy. With respect to long-lasting pain relief and preservation of the endocrine and exocrine functions of the pancreas, DPPHR is a highly effective surgical procedure with a low early and late morbidity and mortality due to limited surgical resection. This technique, introduced into surgical practice by Beger, is indicated in patients with chronic pancreatitis with an inflammatory mass in the head of the pancreas. The authors conclude that this procedure can be performed also in case of pancreatic benign tumors, as microcystic cystadenoma. Advantages of this technique makes DPPHR an attractive alternative to Pylorus-Preserving-Pancreatico-Duodenectomy (PPPD). 相似文献
50.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献