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131.
132.
Nicole Brasseur Karina Lewis Jacques Rousseau Johan E. van Ller 《Photochemistry and photobiology》1996,64(4):702-706
Abstract— The clinical perfusion agent 99m Tc-MIBI was used to monitor changes in tumor vascular perfusion (TVP) induced by Photofrin® (Pll)-mediated photodynamic therapy (PDT). BALB/c mice bearing an EMT-6 tumor on each hind thigh were given an intravenous injection of 1, 2 or 5 mg kg−1 PII. Twenty-four hours later, one tumor was illuminated (600–650 run, 200 mW cm−2 400 J cm−2 ) while the other served as a control. At various time intervals after PDT (0, 2 and 24 h) mice received an intravenous injection of 99m Tc-hexakismethoxy(sobutyusonitri-le (MIBI) (0.18 MBq g−1 ) and were sacrificed 2 min later. The light-treated and the untreated tumors were then dissected, the radioactivity was counted and the percentage of the injected dose per gram of tumor (%ID g−1 ) was calculated as a measure of TVP. We observed that TVP is drug dose dependent, develops progressively with time post-PDT and is inversely related to PDT efficacy. Our data show that early tumor retention of 99m MIBI is a simple method to assess TVP and vascular damage induced by PDT. 相似文献
133.
Suwannee Junyapoon Andrew B. Ross Keith D. Bartle Bernard Frere Alastair C. Lewis Michael Cooke 《Journal of separation science》1999,22(1):47-51
Programmed temperature vaporization injection (PTV) coupled to gas chromatography and atomic emission detector (AED) has been studied for large volume injection of gaseous samples. As examples of the effectiveness of the technique, the results of the analysis of a series of headspace samples of foods such as garlic and onion, and of landfill gases are presented. The volumes of gaseous samples reconcentrated varied from a few milliliters up to liters depending on analyte dilution, through focusing onto a sorbent trap, then rapid liberation into the GC-AED system by programmed thermal desorption. Despite the high carrier gas flow rates associated with direct PTV-GC, AED performance and sensitivity were unaffected. The detailed elemental information obtained from the PTV-GC-AED analyses was confirmed using a PTV coupled to a gas chromatograph with ion trap detector mass spectrometer as detector (PTV-GC-ITD/MS). 相似文献
134.
SimonW. Breeden Andrew Coop StephenM. Husbands JohnW. Lewis 《Helvetica chimica acta》1999,82(11):1978-1980
In the pursuit of ring-constrained analogues of buprenorphine, we wished to prepare 6-O-demethylated analogues of the thevinols and orvinols. Previously it had been disclosed that lithium aluminum hydride (LAH) in THF containing a chlorinated solvent could achieve this transformation. Here we report the results of our work with LAH in the non-coordinating solvent toluene. In refluxing toluene, the selective 6-O-demethylation of thevinols could be achieved with no 3-O-demethylation being observed. It appears that a C(20)−OH or C(20)−NH2 group is needed on the substrate for this hydrogenolysis to proceed. 相似文献
135.
Maram A. Q. Al-Sayaghi Jeremy Lewis Chris Buelke 《International Journal of Polymer Analysis and Characterization》2018,23(6):566-576
Aromatic polyimides are known for their remarkable thermal and chemical properties which are greatly influenced by their precursors. In this study, we report synthesis and characterization of four different aromatic polyimides. The four different dianhydrides (ODPA, BTDA, BPDA, and PMDA) were reacted with a diamine (BisAPAF) via azeotropic imidization under same conditions. FTIR analysis confirmed the formation of aromatic polyimides and all but one polyimide (HPI-BPDA) were found to be completely soluble in common solvents. The obtained molecular weights were between 16,000 and 32,000?g/mol, glass transition temperatures were between 250?°C and 275?°C, degradation temperatures were above 550?°C, and the d-spacing values were around 5?Å. These properties are promising and can be beneficial for various applications such as thin films and membranes. 相似文献
136.
Lawrence JF Niedzwiadek B Menard C Lau BP Lewis D Kuper-Goodman T Carbone S Holmes C 《Journal of AOAC International》2001,84(4):1035-1044
More than 100 samples of blue-green algae products (consisting of Aphanizomenon, Spirulina, and unidentified blue-green algae) in the form of pills, capsules, and powders were collected from retail outlets from across Canada. The samples were extracted with 75% methanol in water and centrifuged to remove solids. Aliquots of the extracts along with spiked blank sample extracts were sent to each participating laboratory and independently analyzed for microcystins by enzyme-linked immunosorbent assay (ELISA), protein phosphatase inhibition assay, and by liquid chromatography-tandem mass spectrometry (LC-MS/MS) after sample cleanup using C18 solid-phase extraction. The results obtained by ELISA and LC-MS/MS agreed very well over a concentration range of about 0.5-35 microg/g. The colorimetric phosphatase results generally agreed with the other 2 methods. While the 2 biochemical assays measured total microcystin content compared with a standard of microcystin LR, the LC-MS/MS method measured specific microcystins (LA, LR, RR, YR) using external standards of these for identification and quantitation. Microcystin LR was found in all positive samples by LC-MS/MS. Microcystin LA was the only other microcystin found in the samples analyzed. These 2 microcystins represent essentially all the microcystins that were present in the extracts. Otherwise, the LC-MS/MS results would have been significantly lower than the results of the biochemical assays had other unknown microcystins been present. 相似文献
137.
Kevin Burgess Brian F.G. Johnson Jack Lewis Paul R. Raithby 《Journal of organometallic chemistry》1982,224(4):C40-C44
Organic azides [N3R] react with [Os3(CO)11(NCMe)] and with [Os3(μ-H)2(CO)10] to form [Os3(CO)10(NCMe)(N3COR)] (R Ph) and [Os3(μ-H)(CO)10(HN3R)] (R Ph, n-Bu, CH2Ph, cyclo-C6H11), respectively; the latter may be converted to [Os3(μ-H)2(CO)9(μ3-NR)] by thermolysis; the molecular structure of the phenyl derivative of each class of compound has been confirmed by x-ray analysis. 相似文献
138.
Larry N. Lewis 《Journal of organometallic chemistry》1982,234(3):355-365
The photoacoustic spectrum (PAS) was measured in the near IR region (1000 to 2600 nm) for organic compounds (C6H6, C6D6, C7H8, and C6H12) and organometallic compounds (Cp2Fe, Cp2Fe2(CO)4, Cp4Fe4(CO)4, Cp4Fe4S4, C6H6Cr(CO)3, CpCo(C4Ph4) and CpCo(CO)2). Band assignments were made by comparison to the infrared spectra. The bands were assigned as the CH overtone stretch and combinations of CH and other IR fundamentals. These bands provide fingerprint spectra for these compounds. 相似文献
139.
Muscarine, oxazole, thiazole, imidazole and peptide alkaloids and other miscellaneous alkaloids. 总被引:1,自引:0,他引:1
J R Lewis 《Natural product reports》1992,9(1):81-101
140.
Woodward C. A. Macinnis J. M. Lewis S. N. Greenbaum E. 《Applied biochemistry and biotechnology》1992,34(1):819-826
Applied Biochemistry and Biotechnology - Normal photosynthesis byCyanidium results in O2 evolution, suggesting that the uptake and subsequent reduction of CO2 also occur. This process, therefore,... 相似文献