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61.
N. M. Blake B. R. Hawkins R. L. Kirk K. Bhatia P. Brown R. M. Garruto D. C. Gajdusek 《American journal of physical anthropology》1983,62(4):343-361
As part of a multidisciplinary survey of populations in the Banks and Torres Islands of Vanuatu and the Southern and Central Districts of the Solomon Islands, nearly 2,400 persons have been tested for ABO blood groups and a number of serum protein and red cell enzyme genetic marker systems. For the ABO system, the populations are characterized in general by high gene O and low gene B frequencies except in two of the Polynesian Outlier Islands, Rennell and Bellona, which have high frequencies of B. Among the serum proteins, several alleles have distributions indicating significant movement of people between islands. These include Albumin New Guinea and the transferrin alleles Tf, and Tf, and Tf. Similar specific alleles for red cell enzymes also show distributions reflecting interisland population movement as well as contact with persons from outside the southern Pacific region. Examples are ACP in the acid phosphatase system, PGM and PGM, PGM and PGM, PGK4 and also HbJTongariki. The data available for 11 polymorphic systems were used to generate genetic distances. Of the four Polynesian Outlier Islands, Anuta is most remote genetically, with Rennell and Bellona also relatively isolated. The fourth Polynesian Outlier, Tikopia, occupies a position genetically close to the Melanesian populations of the Banks and Torres Islands and the southern Solomons. The history of early European contact and voyaging in the Pacific, as well as archaeological and linguistic evidence and local legends, indicate that significant movements of people occurred between islands and provided opportunities for genes to be introduced from Europeans, Africans, and Asians. The genetic marker studies give evidence for genes from all these sources, though at a low level. Despite this admixture, the Polynesian Outlier and Melanesian populations have preserved their own distinctive genetic patterns. 相似文献
62.
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
63.
By coupling Anisakis larval hemoglobin with cyanogen bromide-activated Sepharose, a stable and sensitive antigen for the indirect fluorescent antibody test for anisakiasis was prepared. Using this antigen, cross-reaction with other helminth infections was minimized and the test was greatly simplified.Furthermore, the results obtained indicate that this technique may be useful not only in the sero-diagnosis of anisakiasis but may also be applicable to the diagnosis of other helminthic diseases. 相似文献
64.
E. Follenius 《Cell and tissue research》1970,106(1):61-68
Résumé Dans l'hypothalamus de l'Epinoche, certains prolongements nerveux présentent une organisation particulière du réticulum endoplasmique. Des séries de vésicules interconnectées sont disposées en stries transverses espacées de 0,3 à 1,3 . Cette organisation particulière du réticulum endoplasmique existe dans les prolongements nerveux de fort diamètre (1 ), même dans les fibres neurosécrétrices.
Special organization of the endoplasmic reticulum in some hypothalamic nerve processes ofGasterosteus aculeatus
Summary In some nerve processes of the hypothalamus ofGasterosteus aculeatus, the endoplasmic reticulum displays a special organization. Small interconnected smooth vesicles constitute transverse lines spaced between 0.3 and 1.3 . This special organization of the endoplasmic reticulum has been found in nerve processes with a diameter larger than 1 even in neurosecretory ones.相似文献
65.
Neville W. Pankhurst 《Environmental Biology of Fishes》1989,26(3):201-211
Synopsis Thirty one species of shallow water teleosts were captured from the NE coast of New Zealand. Ocular morphology was assessed in terms of eye size, pupil shape, theoretical sensitivity and acuity based on retinal morphology, and regional distribution of photoreceptors within the retina. Eye size was relatively or absolutely larger in carnivores than herbivores. Diurnal planktivores and nocturnal species of small body size maximise vision by having relatively large eyes. Anterior aphakic spaces were present in most of the species examined, and 25% of the species also had posterior aphakic spaces. Theoretical sensitivity was generally higher among nocturnal than diurnal species, however, a number of benthic and pelagic carnivores showed retinal specialization for enhanced sensitivity. Diurnal species displayed high spatial acuity, with maximum acuity occurring in carnivorous species. Crepuscular species had either high or low acuity, whereas that of nocturnal species was generally lower than in diurnal species. Ten species displayed regional variation in rod density, with crepuscular and nocturnal species showing streaks of high rod density in the retina. Eleven species of carnivores displayed regional variation in cone density, with highest density usually occurring in the caudal part of the retina. In most of the species with areas of high cone density, there was a forward visual axis that coincided with the location of the aphakic space, suggestive of accomodation along that axis. 相似文献
66.
Synopsis The reproductive biology of the coral reef butterflyfish,Chaetodon multicinctus, was investigated by histological examination of gonads sampled over an 18 month period from a shallow inshore population
on Oahu, Hawaii. Most gonads developed directly from previously undifferentiated tissue. Ovarian development (the structural
formation of lamellae and primary oocytes) was observed in fish ≥44 mm and testicular development (the formation of spermatogenic
crypts) in fish ≥62 mm standard length (SL). In addition, testis formation was identified within the ovarian lamellae of several
differentiated but immature fish. It is hypothesized that prematurational sex change may facilitate monogamy within the highly
competitive social structure of this site attached species. Oocyte development in mature females was marked by distinct phases
of primary growth, the formation of yolk vesicles, and vitellogenesis. Spawning activity was histologically identified by
the maturation and hydration of fully yolked oocytes, and presence of postovulatory follicles. Recently spawned females from
field collections and experimental gonadotropin-treatments exhibited postovulatory follicles that were estimated to persist
at least 24 h after ovulation. Atresia of yolked oocytes was classified into four stages of cell degeneration and resorption.
Monthly analyses of oocyte development and atresia within the sample population show thatC. multicinctus has a protracted annual spawning season with a major peak during the early spring and evidence of spawning activity among
some individuals in the fall. Histological analyses of spawning activity provide more accurate and unambiguous information
than do traditional gonadosomatic assays in this and probably other coral reef fishes. 相似文献
67.
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
68.
Phillip S. Lobel 《Environmental Biology of Fishes》1989,24(3):161-171
Synopsis The spawning patterns of four Hawaiian reef fishes with similar reproductive habits, but different biogeographic distributions
were studied from September 1980 to October 1981. Two species are Hawaiian endemics [Centropyge potteri (Pomacanthidae) and Chaetodon multicinctus (Chaetodontidae)] and the other two have pan-tropical Pacific distributions [Ctenochaetus strigosus and Zebrasoma flavescens (Acanthuridae)]. All showed increased spawning activity from January to July, the prevalent pattern among a majority of coastal
marine fishes in Hawaii. Environmental correlatives to the period of peak reproduction include cycles of (a) daylight length
and temperature which probably function as proximate cues and (b) seasonal variations in ocean current patterns which may
ultimately affect survival of larvae and dispersal. Peak reproduction takes place during months when (1) mesoscale eddies
most likely occur, and (2) the probability is greatest of drifting objects remaining near the islands. 相似文献
69.
Phillip S. Lobel 《Environmental Biology of Fishes》1989,25(1-3):125-130
Synopsis Spawning by the banded butterflyfish,Chaetodon multicinctus (Chaetodontidae) was observed on coral reefs off Kona, Hawaii. These fish occurred in male-female pairs during normal daytime
activities, a behavior which is typical for the family. Courtship is also a paired male-female activity. During spawning,
however, other individuals (males?) may intrude on the spawning pair. Spawning typically takes place at least a meter or two
above the bottom. The spawning position consists of the male below and behind the female with his snout against the female's
ventral flank or anal fin area. Intruding individuals may join in when the pair is in position and about to spawn. Intruders
line-up against the male in the same position as he is against his female. Underwater photographs are included to illustrate
these behaviors. 相似文献
70.
严重缺碘对体质及遗传性状影响的研究 总被引:3,自引:2,他引:1
对严重缺碘地区一个容貌特殊,身材较矮,智力低下的人群进行了体质特征及遗传性状的研究,并与国内有关本地区的调查资料进行了对照,提出人类体质特征和遗传性状除与人种、地理环境异同直接相关外,人体不可缺少的微量元素的摄入水平在一定程度上对其也产生影响。并且认为同一人种、民族居住同一地理位置所产生的体质差异应从水文、地质、生活方式、生活水平的不同进行综合分析。 相似文献