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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Underivatized short-chain polysaccharides such as two inulins from different plants containing up to 35-40 monosaccharide units with molecular weights of up to 6500 Da and dextran T 1.5 containing up to 16-20 monosaccharide units with molecular weights of up to 3200 Da have been investigated by direct chemical lionization. Under soft ionization conditions such as ammonia chemical ionization and reduced ion-source temperature, it was possible to obtain spectra of the native polysaccharides showing dominant ion series corresponding to ammonia adduct ions of oligosaccharides, and also ion series corresponding to ammonia adduct ions of anhydro-oligosaccharides.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1540-8183
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Ninety-five patients 75 years or older (range 75–90, mean 79) underwent PTCA from 1987 to 1991. Forty-two patients were 80 years or older. Forty-four had prior MI, 5% had prior coronary bypass surgery (CBS), 13% had a prior history of recent cardiac failure, and 81% (77/95) presented with unstable angina, refractory to intravenous treatment in 31 cases. The mean left ventricular ejection fraction was 62% (range 34%–80%). Thirty-nine percent had single vessel disease, 41% had two vessel disease, and 20% had three vessel disease. Coronary calcifications were present in 28%. A single vessel was dilated in 81 patients, two vessels in 14 patients; complete revascularization was achieved in 41%. The clinical angiographic primary success rate was 79% (75/95). There were five procedural deaths, five MI, five CBS and, ten hematomas. Follow-up data were obtained in 100% cases, with a mean follow-up duration of 12 months (ranging from 1–36). There were four deaths, one MI, and two CBS. Twenty percent (15/74) of patients had a second PTCA with a 73% success rate. Finally, 70% of the initial population was asymptomatic after first or second PTCA at mid-term follow-up. We conclude that PTCA is safe and effective in elderly patients, with 70% clinical success rate at mid-term follow-up in spite offrequent incomplete revascularization limited to the culprit lesion. (J Interven Cardiol 1993; 6:169–174)
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1052-9306
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0951-4198
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: A number of different low molecule weight and volatile compounds have been tested and compared as matrices in 252Cf plasma-desorption mass spectrometry (PDMS) measurements of oligosaccharides. Some heteroaromatic amines (2-aminothiazole and 3-aminopyridine), hydroxyanthraquinones (alizarin and quinalizarin) and phthaleins (fluorescein) proved to be especially suited to enhancing the quasimolecular ion intensity of oligosaccharides. Discrimination effects could be reduced by matrix addition and thus, quantitative results of PDMS could be improved. Oligosaccharides with broad molecular weight distribution (dextrin 10 and dextran T 1.5) have been successfully analyzed by PDMS. The mass spectra obtained compared quite well with ion chromatograms of the respective oligosaccharides.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1573-5044
    Keywords: acylated anthocyanins ; cinnamic acids ; daucus carota (wild carrot) ; flavonoid intermediates ; HPLC separations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Anthocyanins isolated and characterized from the wild carrot suspension cultures used here were 3-O-β-D-glucopyranosyl-(1→6)-[β-D-xylopyranosyl-(1→2)-]β-D〈-galactopyranosylcyanidin (1), 3-O-[β-D- xylopyranosyl-(1→2)-β-D-galactopyranosyl]cyanidin (2), 3-O-(6-O-sinapoyl)-β-D-glucopyranosyl-(1→6)-[β-D- xylopyranosyl-(1→2)-]β-D-galactopyranos ylcyanidin (3), 3-O-(6-O-feruoyl)-β-D-glucopyranosyl-(1→6)-[β- D-xylopyranosyl-(1→2)-]β-D-galactopyranosylcyanidin (4), 3-O-(6-O-coumaroyl)-β-D-glucopyranosyl-(1→6)- [β-D-xylopyranosyl-(1→2)-]β-D-galactopyrano sylcyanidin (5), 3-O-[6-O-(3,4,5-trimethoxycinnamoyl)]-β- D-glucopyranosyl-(1→6)-[β-D-xylopyranosyl-(1→2)-]β-D-galactopyranosylcyanidin (6), 3-O-[6-O-(3,4-dime- thoxycinnamoyl)]-β-D-glucopyranosyl-(1→6)-[β-D-xylopyranosyl-(1→2)-]β-D-galactopyranosylcyanidin (7), 3-O-[(6-O-sinapoyl)-β-D-glucopyranosyl-(1→6)-β-D-galactopyranosyl]cyanidin (8), and 3-O-(β-D-galactopyranosyl)cyanidin (9). Except when cinnamic acids were provided in the culture medium, the major anthocyanin present in the two clones examined was 2. When the naturally occurring and some non-naturally occurring cinnamic acids were provided individually in the medium, 1 and 2 were minor components and the anthocyanin acylated with the supplied cinnamic acid, namely 3, 4, 5, 6, or 7 was the major anthocyanin present in the tissue. When caffeic acid was provided the major anthocyanin in the tissue was 4, thereby suggesting that the caffeic acid was methylated before its use in anthocyanin biosynthesis. Other cinnamic acids supplied had limited effects on the anthocyanins accumulated and appeared not to result in the accumulation of new anthocyanins by the tissue. Thus the tissue can use some but not all analogues of sinapic acid to acylate anthocyanins. Additional anthocyanins were detected in extracts of the wild carrot tissue cultures using mass spectrometry (both MS/MS and HPLC/MS). The additional compounds detected have also been found in cultures of black carrot, an Afghan cultivar of Daucus carota ssp. sativa and the flowers of wild carrot giving no evidence for qualitative differences in the anthocyanins synthesized by subspecies, cell cultures from subspecies, or clones from cell cultures. There are major differences in the amounts of individual anthocyanins found in cultures from different subspecies and in different clones from cell cultures. Here anthocyanins without acyl groups were usually found in the tissues and their accumulation is discussed. On the basis of the structures of the isolated anthocyanins, a likely pathway from cyanidin to the accumulated anthocyanins is proposed and discussed.
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  • 6
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The isobutane and methane direct chemical ionization (DCI) mass spectra of mono- and dianhydrosugars are substantially influenced by their stereochemistry at temperatures of 150-250°C. The best results are obtained under isobutane CI at 200 or 250°C. l,6:3,5-Dianhydrogulofuranose gives proton-bridge stabilized MH+ ions and fewer fragment ions compared with its ido epimer. The four diastereomeric 1,5-anhydropentofuranoses show increased MH+ and M2H+ abundances for the lyxo and ribo isomers with cis-1,2-diol sites capable of proton bridging. The xylo isomer gives a dominant [M — OH]+ ion. All isomers, but especially xylo and ribo, give abundant [C3H5O2]+ skeleton cleavage ions. They are attributed to an RDA fragmentation of pyranoglycosyl-type MH+ ions. The eight diastereomeric 1,6-anhydrohexofuranoses with endo/exo configured triol structures show very characteristic MH+ abundances (4-41% Σ). They parallel the amount of proton solvation in cis-diol sites of the isomers (gluco ≤ ido ≤ altro 〈 gulo 〈 galacto 〈 talo 〈 allo 〈 manno). The [M — OH]+ ion abundances (15-47% Σ) are also very characteristic (galacto ≤ talo 〈 manno 〈 altro ≪ atto 〈 gluco ≤ ido ≪ gulo). They reflect the possible H2O or C4H,OH loss from the MH+ and (M · C4H9]+ ions, respectively, with formation of protonated 1,6:3,5-and 1,6: 23-dianhydrehexofuranose species; the slightly flattened C(5) site of M might favour the departure of the 5-OH group. In addition, there are especially high abundances of skeleton fragment ions, 15% Σ [MH — HCOOH]+, 10% Σ [M — OH — H3O — CH3O]+ and 42% Σ [M — OH — C2H4O2)+, for the ido, galacto and gluco isomers, respectively.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
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