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排序方式: 共有697条查询结果,搜索用时 31 毫秒
171.
Irungu J Dalpathado DS Go EP Jiang H Ha HV Bousfield GR Desaire H 《Analytical chemistry》2006,78(4):1181-1190
Structural analysis of sulfated glycans is essential in understanding their biological significance. Here, we present a new approach to characterize sulfated glycans present on glycoproteins. The analysis is performed on glycopeptides, so information about the sulfated species is obtained in a glycosylation site-specific manner. This method employs an ion-pairing reagent to stabilize the SO3 group of the glycopeptide, allowing useful information to be obtained during MS/MS experiments. The amount of structural information obtained from (+)ESI-MS/MS of the ion-pair complexes for sulfated glycopeptides of equine thyroid stimulating hormone is compared with information obtained by (-)ESI-MS/MS of the underivatized, sulfated glycopeptides. The results indicate that this new method provides detailed insights into the sequence, branching, and type of N-glycans present, compared to analysis via (-)ESI-MS/MS. 相似文献
172.
173.
The retention of Cs+, Cd2+, Pb2+ and Cr3+ by the compounds formed as a result of the hydrothermal treatment of the bottom ash from the fluidized-bed incineration of municipal solid wastes is examined in this work. The amount of Cs+ retained and the distribution coefficient, Kd, were considerably lower than those for Cd2+, Pb2+ and Cr3+, independently of the type of compounds formed by the different bottom ash treatments. The high percentage of Cs+ retained (31%), with a Kd of 222 ml/g, occurred after treatment of the bottom ash in NaOH at 200 degrees C, where zeolite-type A (Na6[AlSiO4]6.4H2O) was the major compound, together with aluminum tobermorite (Ca5Si5Al(OH)O17.5H2O). In the case of Cd2+, Pb2+ and Cr3+, the amount retained was approximately 99% under all of the conditions studied. 相似文献
174.
A Seebeck microprobe (SMP) measurement system has been developed and employed to determine the spatial distribution of the
Seebeck coefficient of a polycrystalline Zn13Sb10 specimen prepared by a gradient freeze (GF) method. The spatial distribution of the Seebeck coefficient strongly reflects
that of the grains observed using an optical polarizing microscope, the magnitude of which ranges from 100 μV/K to 130 μV/K. This fact strongly indicates that the observed spatial distribution of the Seebeck coefficient arises from the anisotropic
Seebeck effect of grains with different crystal orientations in the polycrystalline Zn13Sb10. 相似文献
175.
E Mendel LT Khoo JL Go D Hinton CS Zee ML Apuzzo 《Canadian Metallurgical Quarterly》1999,44(1):203-209
We studied the effects of bile stasis in a guinea pig model of pigment gallstone. The common bile ducts of guinea pigs were partially ligated, and the guinea pigs killed one or two weeks later. Biliary sludge or stones were examined with the Fourier transform infrared spectroscopy and the scanning electromicroscopy. The bile was analyzed for pH, free calcium, bile acids and bilirubin fractions, and the activities of both bacterial and endogenous beta-glucuronidase. After bile duct ligation, calcium bilirubinate precipitates or stones formed in all except one of the animals studied. The bile pH and the proportion of unconjugated bilirubin rose after bile duct ligation, with a concomitant fall of bilirubin monoglucuronide. The activity of bacterial beta-glucuronidase decreased after ligation, while the activity of endogenous beta-glucuronidase rose at week 2. Our results imply that precipitation of calcium bilirubinate in this animal model was induced by an increased bile pH and the nonenzymatic hydrolysis of conjugated bilirubin. 相似文献
176.
177.
J. Go Biowski 《Journal of Materials Science》1999,34(19):4661-4664
The fabrication of the thin piezoelectric layers on the silicon substrate by means of the pulse dc and the dc magnetron sputtering methods is discussed. The influences of the different kind of the surface, the conditions of deposition as well as the process of the thermal stabilising on the properties of the piezoelectric layer were investigated. The results of the investigations of the diffraction spectrum for the thin ZnO films are presented and discussed. The selection of the technological process parameters for the production of the thin ZnO layers in the sensor membranes with the ultrasonic wave generated was analysed. 相似文献
178.
Jun Yong Oh Eunshil Choi Batakrishna Jana Eun Min Go Eunji Jin Seongeon Jin Jinhyu Lee Jong-hoon Bae Gyeongseok Yang Sang Kyu Kwak Wonyoung Choe Ja-Hyoung Ryu 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2300218
Metal-organic framework (MOF) nanoparticles have recently emerged as a promising vehicle for drug delivery with high porosity and feasibility. However, employing a MOF-based drug delivery system remains a challenge due to the difficulty in controlling interfaces of particles in a biological environment. In this paper, protein corona-blocked Zr6-based MOF (PCN-224) nanoparticles are presented for targeted cancer therapy with high efficiency. The unmodified PCN-224 surface is precoated with glutathione transferase (GST)-fused targetable affibody (GST-Afb) proteins via simple mixing conjugations instead of chemical modifications that can induce the impairment of proteins. GST-Afb proteins are shown to stably protect the surface of PCN-224 particles in a specific orientation with GST adsorbed onto the porous surface and the GST-linked Afb posed outward, minimizing the unwanted interfacial interactions of particles with external biological proteins. The Afb-directed cell-specific targeting ability of particles and consequent induction of cell death is demonstrated both in vitro and in vivo by using two kinds of Afb, which targets the surface membrane receptor, human epidermal growth factor receptor 2 (HER2) or epidermal growth factor receptor (EGFR). This study provides insight into the way of regulating the protein-adhesive surface of MOF nanoparticles and designing a more effective MOF-hosted targeted delivery system. 相似文献
179.
Guatemala provides an example of epidemiological superposition, in which health problems typical of developed countries and developing countries are both observed. Nutritional deficiencies in some micronutrients like vitamin A and iron coexist alongside chronic diseases such as diabetes type II and cardiovascular diseases. The importance of black beans in the normal Guatemala diet is well known:70g per capita of black beans are consumed daily. Black beans are an important sources of protein and energy in the diet. They contain "lente" digestion carbohydrates and a high proportion of non-digested carbohydrates that may be fermented in the large intestine. Theses types of carbohydrates are associated with a low glycemic response, low serum cholesterol levels, and a decrease of colon cancer risk factors. These physiological effects may be related to colonic fermentation end products (propionic and butyric acids). Black beans also contain several antinutritional compounds (enzymatic inhibitors, haemaglutenins, saponins and phytic acid, etc.), some of them thermolabiles that are partially eliminated during culinary processes and may modify the nutritional quality of beans. Black beans play a crucial role in the etiology of several diseases in Guatemala. 相似文献
180.