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Plantago exhibit great deal of differences in the breeding system. The reproductive effort calculated on the basis of, (i) dry biomass
of foliar and floral parts and (ii) seed output-weight (mg) per unit leaf area (cm2), exhibits relation with breeding system. The predominantly inbreeding taxa invest higher reproductive effort compared to
their outbreeding allies. In terms of sex allocation strategies, the outbreeding species like P. lanceolata, P. lagopus invest more to the development of floral features and to male functions. On the contrary, inbreeding species such as P. patagonica, P. drummondii, and P. ovata invest greater resources to the female function.
Received 13 April 1998/ Accepted in revised form 6 November 1998 相似文献
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Adem BIC Ahmet AK 《Acta Botanica Sinica》2000,42(8):864-867
Thc pollen grains in the atmosphere of Burdur have been studied for a two-year period(1996through 1997)with a Durham sampler.A total of 11 881 pollen grains belongins to 39 taxa have been identi-fied 相似文献
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Norimah AK H. C. Koo Hamid Jan JM Mohd Nasir MT S. Y. Tan Mahendran Appukutty Nurliyana AR Frank Thielecke Sinead Hopkins M. K. Ong C. Ning E. S. Tee 《PloS one》2015,10(10)
Background
Diets rich in whole grain are associated with several health benefits. Little is known however, about whole grain consumption patterns in Malaysia. The aim of this study was to assess whole grain intakes and dietary source in Malaysian children and adolescents.Methods
This analysis is from the MyBreakfast study, a national cross sectional study investigating eating habits among primary and secondary school children throughout Malaysia, conducted in 2013. Children (n = 5,165) and adolescents (n = 2,947) who completed two days of dietary assessment using a food record or recall respectively were included. The whole grain content of foods was estimated mainly through the use of quantitative ingredient declarations on food labels. All wholegrain foods were considered irrespective of the amount of whole grain they contained.Results
Overall, only 25% of children and 19% of adolescents were wholegrain consumers. Mean daily intakes in the total sample were 2.3g/d (SD 5.8g/d) in children and 1.7g/d (SD 4.7g/d) in adolescents and in the consumer’s only sample, mean intakes reached 9.1g/d (SD 8.6) and 9.2g/d (SD 7.1g/d) respectively. Wheat was the main grain source of whole grain while ready to eat breakfast cereals and hot cereals were the main food contributors. Less than 3% of the children and adolescents reached the US quantitative whole grain recommendation of 48g/day.Conclusion
Whole grain is consumed by only a minority of Malaysian children and adolescents and even among consumers, intakes are well below recommendations. Efforts are needed to firstly understand the barriers to whole grain consumption among Malaysian children in order to design effective health promotion initiatives to promote an increase in whole grain consumption. 相似文献46.
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Tim Downing David J. Lynn Sarah Connell Andrew T. Lloyd AK Fazlul Haque Bhuiyan Pradeepa Silva Arifa N. Naqvi Rahamame Sanfo Racine-Samba Sow Baitsi Podisi Cliona O’Farrelly Olivier Hanotte Daniel G. Bradley 《Immunogenetics》2009,61(4):303-314
There have been significant evolutionary pressures on the chicken during both its speciation and its subsequent domestication
by man. Infectious diseases are expected to have exerted strong selective pressures during these processes. Consequently,
it is likely that genes associated with disease susceptibility or resistance have been subject to some form of selection.
Two genes involved in the immune response (interferon-γ and interleukin 1-β) were selected for sequencing in diverse chicken
populations from Pakistan, Sri Lanka, Bangladesh, Kenya, Senegal, Burkina Faso and Botswana, as well as six outgroup samples
(grey, green, red and Ceylon jungle fowl and grey francolin and bamboo partridge). Haplotype frequencies, tests of neutrality,
summary statistics, coalescent simulations and phylogenetic analysis by maximum likelihood were used to determine the population
genetic characteristics of the genes. Networks indicate that these chicken genes are most closely related to the red jungle
fowl. Interferon-γ had lower diversity and considerable coding sequence conservation, which is consistent with its function
as a key inflammatory cytokine of the immune response. In contrast, the pleiotropic cytokine interleukin 1-β had higher diversity
and showed signals of balancing selection moderated by recombination, yielding high numbers of diverse alleles, possibly reflecting
broader functionality and potential roles in more diseases in different environments.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
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Molecular cloning and characterization of an alpha1,3 fucosyltransferase, CEFT-1, from Caenorhabditis elegans 总被引:2,自引:1,他引:1
We report on the identification, molecular cloning, and characterization of
an alpha1,3 fucosyltransferase (alpha1,3FT) expressed by the nematode,
Caenorhabditis elegans . Although C. elegans glycoconjugates do not express
the Lewis x antigen Galbeta1-- >4[Fucalpha1-->3]GlcNAcbeta-->R,
detergent extracts of adult C.elegans contain an alpha1,3FT that can
fucosylate both nonsialylated and sialylated acceptor glycans to generate
the Lexand sialyl Lexantigens, as well as the lacdiNAc-containing acceptor
GalNAcbeta1-->4GlcNAcbeta1-- >R to generate GalNAcbeta1-->4
[Fucalpha1-->3]GlcNAcbeta1-->R. A search of the C.elegans genome
database revealed the existence of a gene with 20-23% overall identity to
all five cloned human alpha1,3FTs. The putative cDNA for the C.elegans
alpha1,3FT (CEFT-1) was amplified by PCR from a cDNA lambdaZAP library,
cloned, and sequenced. COS7 cells transiently transfected with cDNA
encoding CEFT-1 express the Lex, but not sLexantigen. The CEFT-1 in the
transfected cell extracts can synthesize Lex, but not sialyl Lex, using
exogenous acceptors. A second fucosyltransferase activity was detected in
extracts of C. elegans that transfers Fuc in alpha1,2 linkage to Gal
specifically on type-1 chains. The discovery of alpha-fucosyltransferases
in C. elegans opens the possibility of using this well-characterized
nematode as a model system for studying the role of fucosylated glycans in
the development and survival of C.elegans and possibly other helminths.
相似文献
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A codon-based model designed to describe lentiviral evolution 总被引:7,自引:6,他引:1