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11.
Olga O. Blumenfeld Anthony M. Adamany Karen V. Puglia Wladyslaw W. Socha 《Biochemical genetics》1983,21(3-4):333-348
Chimpanzee erythrocytes express strong M but weak, occasional N blood-group activity, as detected by anti-M and anti-N reagents. We have found that the M activity is carried by a major membrane glycoprotein that is similar but not identical to the human MM glycoprotein (glycophorin A). We have isolated and characterized this glycoprotein from erythrocyte membranes of four individual chimpanzees. The purified glycoproteins strongly inhibited agglutination of M cells by rabbit anti-human M sera and only weakly inhibited the agglutination of N cells by rabbit anti-human N sera. They also displayed medium-to-strong inhibitory activity against chimpanzee iso- and crossimmune antisera tested with chimpanzee erythrocytes of various V-A-B-D and Wc specificities, which are known as chimpanzee extensions of the human type M-N system and the Miltenberger counterpart, respectively. Each glycoprotein was cleaved with CNBr into three fragments, whose size, solubility, and composition were analogous to those obtained by similar treatment of the human M-N antigens. The amino-terminal fragment was found to be a glycooctapeptide whose amino acid composition and partial sequence indicated that it is an intermediate form of the human M and N glycooctapeptides. Its carbohydrate content comprised two threonine-linked saccharide units that, although similar in composition to the human threonine-linked units, were fewer in number than the three units found in the corresponding human glycooctapeptides. Structural similarities to the human antigens strongly suggest that the amino terminus bears the major antigenic determinants of the molecule, and the occurrence in this region of numerous, albeit rare, variants among humans and in chimpanzees indicates that the corresponding coding sequence of the structural gene is particularly susceptible to mutational events. We conclude that the chimpanzee M gene product is a variant of the human type and that the chimpanzee gene is an allele of the human polymorphic M-N locus.This research was supported by National Institutes of Health Grants GM 16389 and HL 19011 and March of Dimes Grant 1-661. 相似文献
12.
Mitsuhiko Sano 《Environmental Biology of Fishes》1989,25(1-3):195-203
Synopsis Stomach content data from 32 species of Japanese butterflyfishes of the family Chaetodontidae were used to classify them into
feeding groups and to determine their important food resources. Four major feeding groups were distinguished: (1) obligative
coral feeders which prey exclusively or mostly on Scleractinian corals, (2) facultative coral feeders that take both corals
and other benthic organisms, (3) noncoralline invertebrate feeders which consume benthic invertebrates other than corals,
and (4) zooplankton feeders. Ten species representing 31% of the butterflyfishes belong to the first category. The second
and third categories include 13 (41%) and 8 (25%) species, respectively. The fourth category is represented by only one species
which picks individual zooplankters, especially calanoid copepods, in midwater above the reefs. Facultative coral feeders
consumed varying quantities of scleractinians (from 2 to 74% of food volume), along with a variety of benthic organisms including
algae, alcyonarians, sea anemones, sedentary polychaetes, sponges, hydroids, etc. Noncoralline invertebrate feeders, on the
other hand, tend to have low diversified diets, predominated by one prey item such as sea anemones, zoanthideans, polychaetes,
or colonial ascidians. These dietary data suggest that scleractinian corals are the most important food resource for the Japanese
butterflyfishes, and next important are sea anemones, sedentary polychaetes, alcyonarians, and algae. 相似文献
13.
The symbiotic effectiveness of Bradyrhizobium strains isolated from three species of Parasponia and from legumes were compared
on Parasponia grown in Leonard-jars. Effectiveness of each symbiotic association was estimated from dry weight and total nitrogen
of shoots and nodules of plants grown on medium free of combined nitrogen. Twenty strains isolated from three species of Parasponia
were found to vary in their effectiveness on P. andersonii, the least effective fixing one fifth of the nitrogen of the most effective strains. The outcome of the symbiosis was not
associated with the host source of the test strain. P. andersonii, P. rugosa and P. rigida responded differently to a selection of seven strains of Parasponia Bradyrhizobium; some strains were either ineffective
or fully effective on each host, while others varied in their symbiotic performance. P. andersonii fixed significantly (P < 0.001) larger quantities of nitrogen than either P. rugosa or P. rigida with p. rigida being the least effective. In contrast to Bradyrhizobium strains from Parasponia spp. which formed nodules rapidly (within 11–20 days), nine strains isolated from legumes required between 25 and 74 days
to form partially effective nodules. The thre Parasponia species formed relatively large quantities of nodule tissue relative to the amount of nitrogen fixed and shoot dry matter
produced. The Bradyrhizobium isolated from Parasponia plants growing in Papua New Guinea soils could be grouped together on
the basis of their infection characteristics on Parasponia and legumes. 相似文献
14.
Z. Satovic A. M. Torres J. I. Cubero 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(7):1130-1138
Thirteen F2 families of faba bean (Vicia faba L.), descended from plants trisomic for chromosomes 3, 4, 5 and 6, have been analyzed for morphological, isozyme and RAPD markers. This allowed the establishment of linkage relationships among these markers as well as the assignment of some markers and/or linkage groups to their respective chromosomes. The linkage analysis of partially overlapping sets of informative genetic markers for the data pooled from 13 F2 families has revealed 48 linkage groups, six of which have been precisely assigned to specific chromosomes. A statistical procedure to analyze the data of joint segregation analysis in families derived from trisomic plants has been developed. 相似文献
15.
16.
Twelve of 24 monospecific caprine reagents produced by absorption of alloimmune antisera identified a complex blood group
system of goats which was designated B, based on the results of a small comparison test with ovine reagents. The frequencies
of the 12 B factors differed significantly among the Australian Angora, Texan Angora, Cashmere, and Dairy goat breeds. Three
of the antigens detected by the reagents were shown to be related as linear subtypes, designated Ba1, Ba2, and Ba3, and inherited as alleles. The segregations of B factors in 80 sire groups involving 1086 offspring demonstrated that groups
of B factors (phenogroups) segregated as products of allelic genes.
This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia. 相似文献
17.
汉族ABO血型的皮纹特征分析 总被引:2,自引:1,他引:1
作者对芜湖地区382例(男220人;女162人)汉族ABO血型的皮纹特征进行了分析,其中O型130人,A型113人,B型101人,AB型38人。分析比较了指纹类型、指纹组合格局、指嵴纹计数、掌嵴纹计数、atd角,掌部真实花纹,掌褶纹和拇趾球纹等项参数,结果表明,ABO各血型的皮纹参数间有若干统计学差异。 相似文献
18.
S. S. Papiha S.M.S. Chahal D. F. Roberts I. P. Singh 《American journal of physical anthropology》1980,53(2):275-283
Data are presented on serological and electrophoretic variants of 18 systems of red cells in 228 individuals belonging to a scheduled tribe (Kanet) and a scheduled caste (Koli) of Kinnar district in Himachal Pradesh, India. Differences in gene frequencies clearly indicate biological distinction in the local population. The possible cause of this genetic heterogeneity is discussed. 相似文献
19.
本文提供了男、女两性共404人ABO、MN血型各表现型的35个体质特征测量数据,对血型和测量体征的关系进行了初步讨论。统计分析表明,不同血型群体的某些单个体征平均值之间有显著差异。对所调查的35个体征作整体分析,可见男性MN系统和女性ABO、MN系统各血型群体平均值之间差异显著。在MN血型系统,MN型群体的测量体征平均值低于M型和N型与MN基因型的杂合状态有密切关系。本文还分析了4个民族的血型资料,表明MN血型在ABO血型系统是随机分布的。 相似文献
20.
L T Nash 《American journal of physical anthropology》1976,44(1):63-77
During a 13 month field study of baboons in the Gombe Stream National Park, Tanzania, the troop under observation divided into two groups. One group left the main troop to become ultimately an independent troop with a separate range. The troop fission followed a period of instability in the male status hierarchy. The events prior to and during the troop fission are described in detail and the membership of the group which left is analyzed. Social bonds prior to the fission, including kinship, determined membership in the group which left. Aggression from members of the main troop played a major role in causing the group which left to establish a new range. This fission is compared with troop fissions observed in rhesus and Japances macaques. 相似文献