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971.
Abstract Murine monoclonal antibodies (mAbs) were selected against a cell wall glycoprotein of Saccharomyces cerevisiae . One of the mAbs (92-276/018) specifically identified S. cerevisiae and the sibling species S. paradoxus, S. pastorianus and S. bayanus in immunofluorescence studies and immunoblot analyses, while no other yeast genera except Saccharomyces were recognized. Further analysis indicated that the mAb 92-276/018 reacts with an epitope in the carbohydrate chain of the cell wall glycoproteins. 相似文献
972.
973.
Michael Landry 《CMAJ》1977,116(12):1392-1394
Although odontogenic keratocysts are benign they are often locally destructive and tend to recur after conservative surgical treatment. They must therefore be distinguished from other cysts of the jaw. Keratocysts possess outpouchings and microscopic daughter cysts from which recurrences may arise. Histologic examination is essential for diagnosis since the appearances on roentgenograms and at operation usually do not reveal the true nature of the lesion. Since many nondental surgeons and pathologists are unaware of odontogenic keratocysts a case is presented in which surgical treatment was originally conservative and finally relatively radical. 相似文献
974.
975.
H Kessler A Haupt M Schudok K Ziegler M Frimmer 《International journal of peptide and protein research》1988,32(3):183-193
Cyclic hexapeptide analogues representing the modified retro sequence of the amino acid residues 7-11 of natural somatostatin are known to protect liver cells from phalloidin poisoning. To determine the influence of steric, lipophilic, and charge effects on (a) the conformation of the backbone and the aromatic side chains and (b) the biological response, the side chains of Phe2, Lys4, and Phe6 of cyclo(-D-Pro1-Phe2-Thr3-Lys(Z)4-Trp5-Phe6-), 1a, one of the most active peptides found so far, were modified by various residues. The discussion of conformationally relevant parameters proves that neither backbone conformations nor populations of aromatic side chain rotamers were altered by these substitutions. The potency of these derivatives in a cytoprotection assay varies by at most one order of magnitude (more or less active than the parent peptide 1a). A qualitative evaluation of lipophilic, steric, and charge effects reveals the dominance of lipophilic effects of aromatic residues; the most potent compounds contain aromatic substructures in the side chain of Lys4. 相似文献
976.
G Maina R J Kessler D E Green 《Biochemical and biophysical research communications》1975,67(4):1567-1574
Insulin, in the presence of Mg2+ and Pi, can transport D-glucose across a bulk phase separating two aqueous phases. All three molecular species (Mg2+, Pi, D-glucose) are transported simulataneously in 1:1:1 stoichiometry. The same system will transport D-galactose and L-arabinose, but not L-glucose, D-arabinose, D-mannitol, D-fructose and 3-0-methyl glucose. Phloridzin completely suppresses transport, not only of glucose, but also of Mg2+ and Pi. Other divalent metal ions are less efficient (Mg2+ >Mn2+ >Ca2+ >Zn2+). The capability of insulin for transport of D-glucose is not duplicated by proinsulin or glucagon. Amino acids and citric cycle substrates are also transported, some as rapidly as D-glucose. Pi is replaceable by phosphate esters such as AMP, ADP and ATP, less efficiently with Mg2+, but more efficiently with Ca2+ as metal ion. The transport of D-glucose in the systems formed by insulin, Ca2+ and nucleotide is less sensitive to phloridzin than the standard Mg2+, Pi system. 相似文献
977.
978.
Using sensitive radio-enzymatic assays, levels of plasma total catecholamines and norepinephrine in rats change dramatically with changes in body temperature. The decrease in plasma catecholamines induced by warming the animal is reflected in an apparent arterio-venous difference when arterial blood is obtained at room temperature and tail sampling is aided by heat induced vasodilation. Combined blockade of extraneuronal and neuronal uptake reduces this arterio-venous difference. Blood samples obtained from the decapitated trunk of the rat contain similar levels of plasma catecholamines as those obtained from indwelling carotid catheters. Blood levels of dopamine-betahydroxylase were similar whether obtained by venous sampling during heat-induced vasodilation, decapitation or indwelling arterial cannula. 相似文献
979.
980.
John H. Pazur Michael E. Tay Beverly A. Pazur Frank J. Miskiel 《Journal of Protein Chemistry》1987,6(5):387-399
Sets of isomeric anti-lactose antibodies with specificity for the lactose units of a cell wall polysaccharide fromStreptococcus faecalis strain N were induced in rabbits immunized with a vaccine of nonviable cells of the organism. Such sets of anti-lactose antibodies
were isolated from the serum of immunized animals by affinity chromatography on lactosyl-Sepharose. Gel electrofocusing experiments
showed that the preparations consisted of multiprotein components. One preparation of antibodies of 13 isomers was separated
into homogeneous components by liquid isoelectrofocusing. The individual isomeric antibodies exhibit specificity for the lactose
units of the antigenic polysaccharide, possess isoelectric points in the range of 5.9–8.0, and belong to the IgG class of
immunoglobulins, and each member yields one light chain and one heavy chain on dissociation in sodium dodecyl sulfate (SDS)
and mercaptoethanol. These results have been interpreted as evidence for the assembly of the chains of isomeric antibodies
by a single-chain pairing mechanism. 相似文献