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941.
942.
Low levels of fetal calf serum (FCS), used as protein supplement in cell culture medium, were traced in preparations of primary murine macrophages (bone-marrow-derived macrophages (BMM) and peritoneal macrophages (PM)). Main components of this common additive were mapped in 2-DE by means of differential image gel electrophoresis and immunoblotting. Additional washing steps in cell preparation helped to decrease the levels of the four highest abundance foetal serum proteins (serum albumin (SA), alpha1-fetoprotein (AFP), alpha1-antitrypsin (alpha1AT) and transferrin (Tf)) to less than 1% of total protein. Macrophage spot pattern was recorded in parallel and showed little variation. Results presented are supposed to be of general interest for cell preparations with similar background. 相似文献
943.
Yang Z Ma X Jancik V Zhang Z Roesky HW Magull J Noltemeyer M Schmidt HG Cea-Olivares R Toscano RA 《Inorganic chemistry》2006,45(8):3312-3315
Three novel aluminum-containing tin(IV) heterobimetallic sulfides are reported. The reaction of [LAl(SLi)2(THF)2]2 (1) [L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3] with Ph2SnCl2, Me2SnCl2, and SnCl4 in THF respectively afforded LAl(mu-S)2SnPh2 (2), LAl(mu-S)2SnMe2 (3), and LAl(mu-S)2Sn(mu-S)2AlL (4) in moderate yields. Compounds 2, 3, and 4 were characterized by elemental analysis, NMR, electron-impact mass spectrometry, and single-crystal X-ray structural analysis. 相似文献
944.
Yang Z Ma X Oswald RB Roesky HW Noltemeyer M 《Journal of the American Chemical Society》2006,128(38):12406-12407
The reaction of LAl (L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3) or LAlH2 with PhB(OH)2 yields the unprecedented spirocyclic LAl[(OBPh)2O] compound. The former reaction proceeds under hydrogen formation and simultaneous oxidation of the aluminum(I). 相似文献
945.
946.
Valincius G McGillivray DJ Febo-Ayala W Vanderah DJ Kasianowicz JJ Lösche M 《The journal of physical chemistry. B》2006,110(21):10213-10216
The rate of Ca2+ -triggered phospholipase A2 (PLA2) degradation of tethered bilayer membranes (tBLMs), composed of a synthetic lipid, beta-mercaptoethanol, and palmitoyloleoylphosphatidylcholine (POPC), is approximately 80 times greater than for those prepared with diphytanoylphosphatidylcholine (DPhyPC). Electrochemical impedance spectroscopy (EIS) and neutron reflectivity (NR) data indicate complete, water-free tBLMs that exhibit near ideal capacitive behavior and the presence of a water reservoir in the bilayer subspace proximal to the substrate (Au) surface for both tBLMs. Together these data indicate that the POPC and the DPhyPC tBLMs are structurally similar along the surface normal but markedly different at the outer leaflet/solution interface and that PLA2 is a sensitive probe of short length scale structural differences not revealed by EIS and NR. 相似文献
947.
Wind M Spickermann J Schleimer M Donzelli M Gebhardt K Sturm-Haurany R Klauer D Fullhardt P Schmitt-Hoffmann A 《Journal of mass spectrometry : JMS》2006,41(7):903-910
The metabolic profile of BAL4815, an antifungal azole drug, was determined using in vitro rat hepatocyte incubations and subsequent analysis by capillary LC-qTof-MS and MS/MS including accurate mass determination. For the detection of the metabolites, a mixture of the drug and its deuterium-labelled analogue was used for incubations. Metabolic stability of BAL4815 was high in cultured rat hepatocytes. However, several low-abundant metabolites were detected by the use of capillary LC-qTof-MS and manual investigation of the data. The peak intensity of the most abundant metabolite was close to the limit of detection. Except for an apparent oxidation product, the masses of the other detected metabolites could not be assigned to a single and frequently occurring biotransformation. Accurate mass determination and possible elemental compositions suggested that metabolism occurred through a combination of glutathionylation and defluorination. This was verified using accurate mass MS/MS. The use of accurate mass measurements and the derived suggestions for the elemental compositions were essential to elucidate this atypical metabolic pathway. A mass accuracy better than 8 ppm could be achieved for most assigned MS and MS/MS signals with intensities less than 6 cps in the spectra. 相似文献
948.
[reaction: see text] The Cu(I)-catalyzed cycloisomerization of tertiary 5-en-1-yn-3-ols with an 1,2-alkyl shift affords stereoselectively tri- and tetracyclic compounds of high molecular complexity. These results are in agreement with a mechanism in which the cyclopropanation precedes the rearrangement. 相似文献
949.
Débora Caperucci Gervásio Henrique Bechara Maria Izabel Camargo Mathias 《Micron (Oxford, England : 1993)》2010,41(7):710-721
The digestive tract of Amblyomma cajennense, as well as other species of ticks, is divided into the anterior, medium and posterior intestines and is the organ responsible for digestion of blood ingested during the meal on the host. The anterior and posterior regions are derived from the ectoderm and the medium one from the endoderm. In the present ultrastructural study, we analyzed the midgut of females in a semi- and fully engorged stages, on the rabbit host, which was subjected to three infestations, where were analyzed the changes that the epithelial cells went through. The results showed that during the feeding period the outermost layer the intestine is composed of muscle fibres, as observed in those semi-engorged and engorged ones in the 1st infestation and semi-engorged in the 2nd infestation. The cytoplasm of digestive cells of feeding females, and those of the semi-engorged and fully engorged in the 1st, 2nd and 3rd infestations showed some intact regions (preserved organelles) with others were disorganized. Large lipid droplets and protein granules were observed in the cytoplasm of the cells of the intestine in all phases of feeding process. Cytoplasmic spherocrystals were only observed in the semi-engorged and engorged females in the 1st and 2nd infestations. Intense vacuolation was observed in the digestive cells of the midgut of semi-engorged and engorged A. cajennense females in the 2nd infestation and those engorged in the 3rd infestation. The data showed that the gut of the females of the A. cajennense tick is actually going through big changes during the feeding period, which become more pronounced when reinfesting. These changes are probably due to the host immune response that returns antibodies to the ectoparasite and thus acquires resistance to their secreted products. 相似文献
950.
Huseyin Tas Lon J. Mathias 《Journal of polymer science. Part A, Polymer chemistry》2008,46(23):7785-7793
New ether dimer (ED‐Od) and diester (ODE) derivatives of α‐hydroxymethylacrylate, each having two octadecyl side chains, were synthesized and (co)polymerized to evaluate the effects of differences in the structures of the monomers on final (co)polymer properties, particularly glass transition temperature. The free radical polymerizations of both monomers yielded high‐molecular weight polymers. Cyclopolymer formation of ED‐Od was confirmed by 13C NMR analysis and the cyclization efficiency (0.95 or greater) was found to be as high as the cyclization efficiencies of the cyclopolymerizations of ether dimers of various alkyl α‐hydroxymethylacrylates synthesized previously. Copolymers of both ED‐Od and ODE with methyl methacrylate (MMA) showed significant Tg decreases over PMMA due to octadecyl side groups causing “internal” plasticization. Comparison of the Tg's of the copolymers of octadecyl methacrylate, ED‐Od and ODE with MMA revealed that the impacts of these monomers on depression of Tg's are identical. That is, the magnitude of decrease in Tg's was quantitatively related to the number of the octadecyl side groups in the copolymers rather than their placement on the same or randomly incorporated repeat units. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7785–7793, 2008 相似文献