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141.
J P Allison M A Pellegrino S Ferrone G N Callahan R A Reisfeld 《Journal of immunology (Baltimore, Md. : 1950)》1977,118(3):1004-1009
HLA antigens of both the A and B loci were shown to be associated with the high density lipoprotein fraction of serum prepared by ultracentrifugal flotation. HLA-A9 antigens were purified 100-fold with essentially complete recovery by a simple procedure of high density lipoprotein preparation involving precipitation with polyanions and ultracentrifugal flotation. The purified lipid-associated antigen was immunogenic since it elicited the formation of cytotoxic xenoantibodies in rabbits. Serum HLA-A9 antigens were found by immunoprecipitation and gel electrophoresis to consist of a 45,000 m.w. heavy chain associated with beta2-microglobulin. The size of the HLA-lipid complex (less than 190,000 m.w.) and of the HLA-deoxycholate complex (less than 102,000 m.w.) suggests that HLA antigens are shed into plasma as a complex of a single HLA molecule and a single beta2-microglobulin chain, associated with boundary lipid. 相似文献
142.
From the aerial part of Teucrium chamaedrys a new neo-clerodane diterpenoid, dihydroteugin, has been isolated, besides the previously known diterpenoids teucrin A and teugin. The structure of dihydroteugin, (12S)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16), 14-diene-18,19:20,12-diolide, was established by chemical and spectroscopic means and by partial synthesis from teugin. 相似文献
143.
Vincenzo Carelli Felice Liberatore Antonio Casini Rosanna Mondelli Alberto Arnone Italo Carelli Giuseppe Rotilio Irene Mavelli 《Bioorganic chemistry》1980,9(3):342-351
The composition and the structure of the product from the known electrochemical dimerization of the NAD+ have been conclusively demonstrated. A detailed analysis of the 1H and 13C nmr spectra has in fact led to the conclusion that the product contains three diastereoisomeric dimers of the 4,4′-tetrahydrobipyridyl type. Furthermore, the cytoplasmic fraction obtained from a standard mitochondrial preparation of rat liver has been shown to catalyze the oxygen uptake by the dimers. A 1 : 1 molar ratio of the reagents in the redox process is indicated by manometric data on oxygen uptake complemented by spectrophotometric analysis of the oxidized substrates, suggesting that H2O2 is the reduction product. NAD+ was identified as the oxidation product by an enzymatic method. 相似文献
144.
A total of 51 restriction sites were recognized within the BK virus genome by the combination of 10 different restriction endonucleases. These sites were mapped and oriented relative to one another as well as to the five fragments generated by the digestion of BK virus DNA with HindIII and EcoRI. The result was a comprehensive physical map suitable for in-depth characterization of the functions of BK virus at the molecular level. 相似文献
145.
C Mangoni di S Stefano M Ruggiero M Brunese S Morelli 《Bollettino della Società italiana di biologia sperimentale》1979,55(14):1398-1404
Metabolic rate of obese patients is reported, recorded to cellular active mass. The metabolic rate is higher in obese patients and the value is diucthy related to individual actual weight. The dinamic-specific action of proteins is normal. 相似文献
146.
147.
A combination of serological (cytotoxicity, binding assay, lysostrip) and immunochemical (indirect immunoprecipitation, sequential immunoprecipitation, two-dimensional gel electrophoresis) assays have shown that the monoclonal antibody Q6/64 recognizes an antigenic determinant which is expressed by certain gene products of the A and B loci of the HLA region. The determinant identified by Q6/64 is spatially close to those which define the serological polymorphism of the HLA-A, B, C antigenic system. The results presented in this study in conjunction which those recently published by other investigators indicate that sharing of determinants among HLA-A and -B allospecificities is more frequent than originally assumed on the basis of the cross-reactivity pattern obtained with alloantisera. This conclusion is in agreement with the high degree of homology in the primary amino-acid sequence of A and B allospecificities. 相似文献
148.
149.
Vito Quaranta Michele A. Pellegrino Gerald N. Callahan Soldano Ferrone 《Immunogenetics》1981,13(4):311-317
The anti-H-2 alloantiserum D-32 [(BlO.A(2R) × C3H.SW) anti-C3H] is cytolytic to human lymphocytes. Fab2 blocking assays, indirect immunoprecipitation and sequential immunoprecipitation experiments showed that the anti-H-2 alloantiserum D-32 recognizes antigenic determinants which are expressed on the heavy chain of subpopulations of HLA-A, B antigens. These determinants are different from those defining the serological polymorphism of the HLA-A, B, C system, are the same as or spatially close to those recognized by the anti-HLA-A, B monoclonal antibody Q6/64 and are expressed on rabbit, rat or guinea pig lymphocytes. 相似文献
150.
Michael Fernandes Gaddo Onesti Roberto Fiorentini Giuseppe Bellini Anne B. Gould Kwan Eun Kim Charles Swartz 《Life sciences》1977,20(4):623-626
Renal hypertension was induced by ligation of the aorta between renal arteries in rats sympathectomized with 6-hydroxydopamine. In the early phase, equally severe hypertension developed in the denervated group as compared to innervated controls. Later, blood pressure was lower in the denervated rats. Initially, increases in plasma renin were seen in both groups; the levels, however, were markedly lower in the denervated rats. Later, the renin levels were similar and not different from baseline. It is concluded that adrenergic neural activity is not essential in the development of renal hypertension; the maintenance of the chronic state, however, depends in part on adrenergic innervation. 相似文献