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111.
Summary 1242 HLA-ABC haplotypes of the North German population (Hamburg) as deduced by family analyses are described. They are in perfect agreement with recently published data by Mayr (1977) from Austria (Vienna) in all parameters tested: frequency of the single HLA-alleles, haplotype distribution and linkage disequilibrium values. Gametic association studies revealed that 69.4% of the B and C genes (map distance 0.2 cM) 36.9% of the A and C genes (0.6 cM), but only 23.2% of the A and B genes (0.8 cM) were significantly more often combined than expected due to their frequencies. From these findings it seems likely that the linkage disequilibrium within the MHC is rather due to a short evolutionary period than to selective forces. Some observations as to the most common European haplotype A1,B8 are discussed. 相似文献
112.
Antonín Vězda 《Folia Geobotanica》1978,13(1):99-102
Eine nèue foliikole Flechte (Pleurotrema epiphylla sp. n.) aus Zaïre (Zentral-Afrika) wird beschrieben. Die systematischen Beziehungen der neuen Art zu den anderenPleurotrema-Arten und die Stellung der GattungPleurotrema innerhalb der FamilieParatheliaceae wird kurz diskutiert. 相似文献
113.
John Leo Abernethy Charles M. Lovett Anton Haddad Jeff D. Felberg 《Bioorganic chemistry》1982,11(3):251-261
Acylated crude papain has been shown to exert stereoselective behavior toward racemic hydrazides devoid of an amino acid residue, namely, (RS)-mandelic and (RS)-atrolactic hydrazides. These hydrazides functioned as nucleophiles to yield N1,N2-diacylhydrazines. Several achiral acylating agents for the enzyme were chosen, including Z-glycine, BOC-glycine, AOC-glycine, and hippuric acid. With the exception of hippuric acid as the acylating agent, the reaction product, in every instance for these achiral hydrazides, consisted of an excess of the (+)-N1,N2-diacylhydrazine. The relative rates of product formation for the mandelic hydrazides were considerably greater than for corresponding reactions with racemic atrolactic hydrazide. When chiral Z-l-alanine was employed to acylate crude papain, the stereoselective action was most pronounced, with the formation of a mixture of diastereoisomers consisting of 73% N1-(Z-l-alanyl)-N2-[(R)-mandelyl]hydrazine. The relative reactivities for the electrophiles was Z-l-alanine ? Z-glycine ? hippuric acid ? AOC-glycine > BOC-glycine. The hydrazides of (R)-, (S)-mandelic, and (RS)-atrolactic acids were prepared by conversion of the corresponding acids to their esters by means of a catalytic dehydrating agent and subsequent treatment with a methanolic solution of hydrazine. 相似文献
114.
An ultracentrifugation procedure is described to concentrate protein solutions on the microliter scale. Protein solutions were centrifuged in U-shaped lengths of polyethylene tubing at 160 000 × g for 15 h and thereafter fractionated by cutting the tubing. The method can be performed in a conventional ultracentrifuge and needs no special equipment. 相似文献
115.
Summary Treatment of human lymphocytes in vitro with trimethylpsoralen or 8-methoxypsoralen and UVA irradiation (PUVA) induced chromosome damage, mainly constrictions and gaps, but also breaks and exchanges, and increased the frequency of sister chromatid exchange (SCE). The localization of the chromosome aberrations was nonrandom. The coincidence of many PUVA hits with mercaptoenthanol hits suggests that PUVA may have other targets in the cell than the DNA, perhaps the folding proteins of the chromosomes and the nuclear membrane/chromatin attachment organelles.Caffeine increased in a synergistic way the chromosome aberration yield if added after PUVA treatment, but there was no effect when caffeine was present before and during PUVA treatment. The SCE frequency was increased in the presence of caffeine. 相似文献
116.
Anton Weber 《Plant Systematics and Evolution》1977,127(2-3):201-216
Within the genusLoxonia
Jack, currently regarded as monotypic, three species are recognized:L. hirsuta
Jack (Sumatra, Mentawai-Islands, Java, Borneo, Anambas-Islands, Malay Peninsula),L. discolor
Jack (Sumatra) andL. burttiana
A. Weber, spec. nova (Borneo). [Key with English translation p. 203.] There is evidence thatL. discolor is the most primitive species within the genus, the two others being derived from it.
Teil V der Beiträge zur Morphologie und Systematik derKlugieae undLoxonieae (Gesneriaceae). 相似文献
117.
Marden A. de Alvarenga Raimundo Braz Fo Otto R. Gottlieb João P. de P. Dias Aderbal F. Magalhães Eva G. Magalhães Gouvan C. de Magalhães Mauro T. Magalhães José G.S. Maia Raquel Marques Anita J. Marsaioli Antônio A.L. Mesquita Anselmo A. de Moraes Alaide B. de Oliveira Geovane G. de Oliveira Gentil Pedreira Sebastião K. Pereira Sonildes L.V. Pinho Celira C. Santos 《Phytochemistry》1978,17(3):511-516
Wood samples, infested by fungi during storage, were shown to contain, besides the known 5-methyl-mellein, additional (3R)-8-hydroxy-3-methyl-3,4-dihydroisocoumarins substituted by 7-methyl, 5-formyl, 5-carboxy, 5-hydroxy, 5-methoxy, 6-methoxy-5-methyl and 6,7-dimethoxy-5-methyl groups, as well as 6-formyl-7-hydroxy-5-methoxy-4-methylphthalide. Several 2-methylchromanones were synthesized in order to show that this class of compounds can be distinguished from 3-methyl-3,4-dihydroisocoumarins by MS. 相似文献
118.
John H. Collins Bliss Forbush Lois K. Lane Eleanor Ling Arnold Schwartz Anita Zot 《生物化学与生物物理学报:生物膜》1982,686(1):7-12
Highly purified lamb kidney (Na++K+)-ATPase was photoaffinity labeled with the tritiated 2-nitro-5-azidobenzoyl derivative of ouabain (NAB-ouabain). The labeled (Na++K+)-ATPase was mixed with unlabeled carrier enzyme. Two proteolipid (γ1 and γ2) fractions were then isolated by chromatography on columns of Sepharose CL-6B and Sephadex LH-60. The two fractions were interchangeable when rechromatographed on the LH-60 column, suggesting that γ1 is an aggregated form of γ2. The total yield was 0.8–1.5 mol of γ component per mol of catalytic subunit recovered. This indicates that the γ component is present in stoichiometric amounts in the (Na++K+)-ATPase. The proteolipids that were labeled with NAB-ouabain copurified with the unlabeled proteolipids. 相似文献
119.
Willem Nieuwenhuizen Jef J. Emeis Anton Vermond 《Biochemical and biophysical research communications》1982,105(3):1122-1127
Solubilization of fibrin monomers (Fm's) is usually performed with dilute acetic acid, urea or sodium bromide. These solvents can affect the biological properties of Fm's. Therefore we describe a new method to keep Fm's in solution, under milder conditions i.e. by generating them in Dcate solutions and avoiding non-physiological conditions. The in vivo behaviour of iodinated rat Fm's injected in rats and prepared by this new method was compared with that of Fm's dissolved in acetic acid, urea or sodium bromide.Fm's prepared in Dcate solutions accumulate rapidly, within 10 minutes after injection, in all organs tested, predominantly in kidney, liver and lung, probably by interaction with endothelial cells. The blood radioactivity remains nearly constant during the first 90 minutes and decreases thereafter exponentially. Fm's dissolved in sodium bromide behave similarly. However, Fm's dissolved in acetic acid or urea behave differently and do not accumulate in organs. This suggests that Fm's loose their capability to accumulate in organs and probably to interact with endothelial cells when they have been dissolved in acetic acid or urea.The slow exponential clearance phase does not differ significantly between the various Fm's and their are estimated to lie between 5 and 7 hours. 相似文献
120.
Antonín Vězda 《Folia Geobotanica》1983,18(1):45-70
This paper deals with 19 species of foliicolous lichens collected in the summer months of 1977 to 1980 during several excursions to the vicinity of the spas Sochi, Gagra and Sukhumi on the east shores of the Black Sea (part of the Colchis). Some new taxa and one new combination are proposed:Raciborskiella minor Vězda (sp. n.),Porina colchica Vězda (sp. n.),Gyalectidium caucasicum (Elenk. etWoronich.)Vězda (comb. n.),G. colchicum Vězda (sp. n.),Bacidia vasakii Vězda (sp. n.). Taxonomical, ecological and plant geographical notes to all species are given. 相似文献