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1.
In this paper, data on genetic distances among five tribal populations ae given. Among the five tribes, Koya Dora, Raj Gond and Naikpod are autochthonous populations of the Deccan plateau whereas the other two groups, Pardhan and Lambadi are migrants. Kova Doras were sampled from five distant localities. Genetic markers typed are: A1A2B0, Rho(D) blood group systems glucose-6-phosphate dehydrogenase deficiency, transferrin, haptoglobin, groupspecific component, haemoglobin, colour-vision deficiency and tastability to P. T. C. Using frequency data for the above nine genetic loci, genetic distances between the five endogamous tribes, and between the five groups of Koya Dora are calculated by adopting the statistical method of Edwards (1971). While genetic distances between Koya Dora, Raj Gond and Lambadi are minimal, the genetic distance between Pardhans and other tribal groups is maximum. Naikpods occupy an intermediate position. The closeness of Lambadi with Koya Dora and RAJ Gond can be regarded as coincidental. Interestingly, the differences in the genetic distance values between five Koya Dora groups are as great as the differences between the five endogamous tribal populations tested for the same loci. Genetic affinities of these tribal populations are discussed in relation to their ethnic origin migration and geographical isolation.  相似文献   

2.
A 57-kb region of tomato chromosome 7 harboring five different genes was compared with the sequence of the Arabidopsis genome to search for microsynteny between the genomes of these two species. For all five genes, homologous sequences could be identified in a 30-kb region located on Arabidopsis chromosome 1. Only two inversion events distinguish the arrangement of the five genes in tomato from that in Arabidopsis. Inversions were not detected when the arrangement of the five Arabidopsis genes was compared with the arrangement in the orthologous region of Capsella, a plant closely related to Arabidopsis. These results provide evidence for microcolinearity between closely and distantly related dicotyledonous species. The degree of microcolinearity found can be exploited to localize orthologous genes in Arabidopsis and tomato in an unambiguous way.  相似文献   

3.
Asteraceae account for 10% of all flowering plant species, and 35%–40% of these are in five closely related tribes that total over 10 000 species. These tribes include Anthemideae, Astereae, Calenduleae, Gnaphalieae, and Senecioneae, which form one of two enormous clades within Subfamily Asteroideae. We took a phylogenomics approach to resolve evolutionary relationships among these five tribes. We sampled the nuclear and plastid genomes via HybSeq target enrichment and genome skimming, and recovered 74 plastid genes and nearly 1000 nuclear loci, known as Conserved Orthologous Sequences. We tested for conflicting support in both data sets and used network analyses to assess patterns of reticulation to explain the early evolutionary history of this lineage, which has experienced whole‐genome duplications and rapid radiations. We found concordance and conflicting support in both data sets and documented four ancient hybridization events. Due to the timing of the early radiation of this five‐tribe lineage, shortly before the Eocene–Oligocene extinction event (34 MYA), early lineages were likely lost, obscuring some details of their early evolutionary history.  相似文献   

4.
Abstract. We tested the following hypotheses forthe first five years of a grassland succession: (a) community changes are mainly directional and related to time after disturbance ratherthanto environmental fluctuations; (b) rates of succession decrease over time, and (c) plant communities in different plots converge on a similar composition within five years of succession. We tested those hypotheses using a Principal Components Analysis applied to data from four successional plots established in successive y ears in a large cropland in the Inland Pampa, Argentina. Community changes were correlated to the age of the plots, and unrelated to rainfall variability, a major environmental variable in grasslands. Successional rates were constant over the five years, probably because of the continued dominance of different annuals; we conclude that successional rates depend on the life history of the dominant species rather than on any emergent community property. We found no evidence of convergence ordivergence; we concluded that the results of successional studies may depend on the temporal and spatial scale of observation.  相似文献   

5.
This paper reports an immunochip for the detection of five kinds of chemicals: atrazine, nonylphenol, 17-beta estradiol, paraverine and chloramphenicol, which are harmful to human health and environment due to unconscionable use or abuse. Five antigen conjugates were synthesized, purified and then labeled with Cy3 dye. Meanwhile, the immunochip was prepared by immobilization the five kinds of specific antibodies on aldehydized slides as probes. A series of experimental conditions were optimized and selected. Standard curves were plotted and the detection ranges were 0.001-5 microg/mL with good logistic correlation and linear correlation (R(2)>0.99). All the five chemicals can be simultaneously and quantitatively determined in a chip, and the relative standard deviations were within 10%. The immunochip will become a highly sensitive, rapid, alternative analytical tool for detection of chemicals or toxicants.  相似文献   

6.
The length‐weight relationships and new total length are described for five fish species in the Pengxi River basin of the Three Gorges Reservoir. Fish were occasionally sampled from five sites between 2009 and 2014, using various gill nets (mesh size range 2–12 cm) and electrofishing. For four of the five species studied a new maximum total length not yet recorded in previous length‐weight estimates have been found. These data will help to convert length data from field studies in the Three Gorges Reservoir into weight and biomass.  相似文献   

7.
Human chorionic gonadotropin (hCG), human luteinizing hormone, human thyroid-stimulating hormone, and human follicle-stimulating hormone are closely related family of proteins which share a common alpha-subunit. However, their sugar moieties are quite different. hCG contains five acidic asparagine-linked sugar chains. These five sugar chains are derived by sialylation from three neutral oligosaccharides: two biantennary (N-1 and N-2) and one monoantennary (N-3) complex-type oligosaccharides. Although hCG purified from the urine of pregnant women is more enriched in sialylated sugar chains than that purified from placenta, the molar ratio of N-1, N-2, and N-3 of these two hCGs are the same (1:2:1). Comparative study of the sugar moieties of the alpha- and beta-subunits of hCG revealed that alpha contains 1 mol each of N-2 and N-3, while beta contains 1 mol each of N-1 and N-2. This specific distribution of oligosaccharides at the four asparagine loci of the hCG molecule is now helping us to consider the functional role of the sugar moiety of glycohormones. hCG is produced not only by the trophoblast but also by various trophoblastic diseases. The hCGs purified from the urine of patients with hydatidiform mole contain the same oligosaccharides as normal hCG. However, those from the urine of choriocarcinoma patients contain five additional neutral oligosaccharides. In contrast, hCGs from invasive-mole patients contain three of the five oligosaccharides, specifically found in choriocarcinoma hCGs. The malignant transformational change of the sugar moiety of hCG can be explained by an increase of a fucosyltransferase, which forms the Fuc alpha 1----6GlcNAc group and by ectopic expression and subsequent modification of N-acetylglucosaminyltransferase IV. The appearance of tumor-specific sugar chains of hCG has been used to develop a new diagnostic method for invasive mole and choriocarcinoma.  相似文献   

8.
The inheritance of mitochondrial genes and genomes are uniparental in most sexual eukaryotes. This pattern of inheritance makes mitochondrial genomes in natural populations effectively clonal. Here, we examined the mitochondrial population genetics of the emerging human pathogenic fungus Cryptococcus gattii . The DNA sequences for five mitochondrial DNA fragments were obtained from each of 50 isolates belonging to two evolutionary divergent lineages, VGI and VGII. Our analyses revealed a greater sequence diversity within VGI than that within VGII, consistent with observations of the nuclear genes. The combined analyses of all five gene fragments indicated significant divergence between VGI and VGII. However, the five individual genealogies showed different relationships among the isolates, consistent with recent hybridization and mitochondrial gene transfer between the two lineages. Population genetic analyses of the multilocus data identified evidence for predominantly clonal mitochondrial population structures within both lineages. Interestingly, there were clear signatures of recombination among mitochondrial genes within the VGII lineage. Our analyses suggest historical mitochondrial genome divergence within C. gattii , but there is evidence for recent hybridization and recombination in the mitochondrial genome of this important human yeast pathogen.  相似文献   

9.
Two new chromosome complements of Aotus trivirgatus griseimembra are described making a total of five different karyotypes observed in this subspecies inhabiting Panama and the northwestern part of Colombia, South America. Detailed comparisons of the G-banded chromosomes of these five karyotypes suggest that the polymorphism of chromosome numbers 56 and 55 in Panamanian Aotus and 54, 53, and 52 in Colombian Aotus stems primarily from a Robertsonian translocation mechanism involving pairs B13 and B14 (or A1). A second Robertsonian translocation mechanism involving pairs B28 and B29 (or A2) constitutes the karyotypic differences between the two chromosomal races.  相似文献   

10.
Abstract Eight families of Symphyta for the Western Hemisphere south of the United States are reviewed: Xyelidae (one genus, two species), Pamphiliidae (one genus, four species), Cimbicidae (five genera, nine species), Diprionidae (three genera, thirteen species), Xiphydriidae (four genera, seventeen species), Siricidae (six genera, nine species), Orussidae (five genera, twelve species), and Cephidae (one genus, one species). New taxa are Acantholyda nigrostigmata (Pamphiliidae); Zadiprionfalsus, Neodiprion bicolor, N.equalis, N.omosus (Diprionidae); Derecyrta circularis, Steirocephala lateralba (Xiphydriidae); Sirotremex, S.flammeus (Siricidae); and Ophrynopus depressatus, O.plaumanni (Orussidae). Lopesiana is a new name for Lopesia Conde (Cimbicidae). Three new combinations and six new synonyms are proposed. The Xyelidae, Pamphiliidae, Diprionidae, Siricidae and Cephidae are primarily northern groups with southern extensions into Mexico, Central America and/or Cuba. The Cimbicidae, Xiphydriidae and Orussidae are more generally distributed throughout the neotropics. Keys to families, genera and species are provided.  相似文献   

11.
广西兰科植物增补   总被引:3,自引:0,他引:3  
报道了广西兰科植物区系 2个新记录属和 5个新记录种。  相似文献   

12.
Lysosomal enzymes require a mannose 6-phosphate recognition marker, constructed on asparagine-linked oligosaccharide chains, for targeting to lysosomes. We have identified the glycosylation sites of human beta-hexosaminidase B and have determined the influence of individual oligosaccharides on the phosphorylation, lysosomal targeting, and catalytic activity of the enzyme. The five potential glycosylation sites of the hexosaminidase beta-chain were modified individually by site-directed mutagenesis, and the constructs were expressed in COS 1 cells. By this analysis, we determined that four of the five potential sites were glycosylated. Two of the four oligosaccharides were preferentially phosphorylated. The absence of these two preferentially phosphorylated oligosaccharides resulted in greatly reduced amounts of the lysosomal form of the enzyme with increased secretion into the medium. The catalytic activity of beta-hexosaminidase B was not significantly altered by the absence of individual oligosaccharides suggesting the folding and assembly of the enzyme was not disrupted.  相似文献   

13.
Three of the five major species of catfishes in Lake Victoria displayed continuous, protracted (fractional) spawning activity with half or more of the population in gonadal stages IV–VI. Pulses in reproductive activity occurred in all species and were generally positioned between the established, rainy seasons for East Africa. Although highly variable, relative fecundity was positively correlated with body length and weight of fish in all species. All five species matured sexually between their first and third year of life.  相似文献   

14.
SUMMARY. Growth rates of Amphinemura sulcicollis were investigated at five main stations in the upper River Wear, Northern England. Retardation of growth was noted during November, December and January and comparison was made of the degree of such retardation at high and low stations.  相似文献   

15.
To clarify the taxonomic status of the Burmoniscus ocellatus complex in Japan, we carried out morphological observations and phylogenetic analyses of specimens collected from Yonagunijima, Iriomotejima, Ishigakijima, and Miyakojima Islands of the southern Ryukyus and from Okinawajima Island of the central Ryukyus in southwestern Japan. Observations of the holotypes of Aphiloscia iriomotensis ( Nunomura, 1986 ), Ap. ishigakiensis ( Nunomura, 1986 ), and Ap. yonakuniensis ( Nunomura, 1986 ), in addition to the specimens newly collected from the five islands, indicated that these specimens belong to the genus Burmoniscus. Analyses of five morphological characters of 268 specimens collected from the five islands showed that the body size of Okinawajima specimens is distinctly smaller than those of the specimens from the southern Ryukyus. The ranges of the five morphological characters tended to overlap among the specimens from Yonagunijima, Iriomotejima, Ishigakijima and Miyakojima Islands; these morphological characters were congruent with those of 6. ocellatus (Verhoeff, 1928). The phylogenetic analyses were based on three regions of mitochondrial DNA-COI, 12S rRNA, and 16S rRNA-and indicated that the specimens collected from the southern Ryukyus constitute a monophyletic group, which is clearly distinct from the clade composed of the Okinawajima specimens. These results strongly suggest that Ap. iriomotensis, Ap. ishigakiensis, and Ap. yonakuniensis are synonymous with B. ocellatus, a species widely distributed in the southern Ryukyus. On the other hand, the species from Okinawajima Island in the central Ryukyus is considered to be an undescribed Burmoniscus species, which is closely related to but clearly distinct from S. ocellatus.  相似文献   

16.
Our studies of the external morphology of five species of deepwater skates (Amblyraja jenseni, Bathyraja pallida, B. richardsoni, Rajella bigelowi, and R. kukujevi) showed that their males and females differ significantly in 9 characters in the first species, 14 characters in the second, 11 characters in the third and fourth, and 10 characters in the fifth. Sexual differences occur most frequently in the length of the first gill slit (in four species out of five), the length of the nasal curtain, the mouth width, and the length of the third gill slit (in three species out of five), the width and length of the disc, the length of the first and second dorsal fin bases, the tail height at the tip of the ventral fin, the length of the fifth gill slit, the distance between the first and fifth gill slits, the interspiracular distance, the preanal length, distance from the tip of the snout to the maximum disc width, and the interorbital distance (in two species out of five).  相似文献   

17.
A comparative study was made of nine commonly used membrane filters from five manufacturers, all recommended for enumeration of coliform bacteria. Bacterial recoveries and flow rates were examined from three types of water and were found to correlate with the surface pore structure determined by scanning electron microscopy. The sorption of metals was also determined. The results of these studies indicate that the five best membranes for fecal coliform recovery could be placed in two groups: Millipore HC and Gelman, followed by Johns-Manville SG and AG and Sartorius 13806.  相似文献   

18.
Although in these five genera the long broad first primary and rounded wing agree with Timalia pileata, as does the profile of the bill of Argya fulvus and Argya rubiginosus, they do not do so in any other respect,. neither in their habits, nest and eggs, nor in the scutation of the tarsus. We therefore propose to remove them all from the Timaliidae and place them in two separate families, but leaving them in their present position in the classification as placed by Sclater in Syst. Av. Æthiop. ii. 1930.  相似文献   

19.
This paper provides the length‐weight and length–length relationships for five fish species in the Zigui section of the lower Three Gorges Reservoir of the Yangtze River. Specimens were collected from December 2014 to January 2017, using various types of fishing gear and electroshock fishing techniques. Length‐weight relationships (LWRs) for one fish species and Length–length relationships (LLRs) for five fish species are unknown to FishBase. New maximum total lengths for four species were also recorded for FishBase. Moreover, standard‐length to total‐length equations for converting size measurements for these five species are presented.  相似文献   

20.
Pure cultures of Bacillus cereus, Pseudomonas fluorescens, and Achromobacter sp. were shown to transform five pyrethroid insecticides in the presence of Tween 80. One of the major products, 3-phenoxybenzoic acid, was further transformed to 4-hydroxy-3-phenoxybenzoic acid. Permethrin was the most rapidly transformed of the pyrethroids, with a half-life of less than 5 days.  相似文献   

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