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21.
Synonymous substitution rates have been shown to vary among evolutionary
lineages of both nuclear and organellar genes across a broad range of
taxonomic groups. In animals, rate heterogeneity does not appear to be
correlated across nuclear and mitochondrial genes. In this paper, we
contrast substitution rates in two plant groups and show that grasses
evolve more rapidly than palms at synonymous sites in a mitochondrial, a
nuclear, and a plastid gene. Furthermore, we show that the relative rates
of synonymous substitution between grasses and palms are similar at the
three loci. The correlation in synonymous substitution rates across genes
is particularly striking because the three genes evolve at very different
absolute rates. In contrast, relative rates of nonsynonymous substitution
are not conserved among the three genes.
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Lewis Landsberg MD Louis J. Aronne MD Lawrence J. Beilin MB BS MD MA Valerie Burke MD Leon I. Igel MD Donald Lloyd‐Jones MD ScM James Sowers MD 《Obesity (Silver Spring, Md.)》2013,21(1):8-24
In light of the worldwide epidemic of obesity, and in recognition of hypertension as a major factor in the cardiovascular morbidity and mortality associated with obesity, The Obesity Society and The American Society of Hypertension agreed to jointly sponsor a position paper on obesity‐related hypertension to be published jointly in the journals of each society. The purpose is to inform the members of both societies, as well as practicing clinicians, with a timely review of the association between obesity and high blood pressure, the risk that this association entails, and the options for rational, evidenced‐based treatment. The position paper is divided into six sections plus a summary as follows: pathophysiology, epidemiology and cardiovascular risk, the metabolic syndrome, lifestyle management in prevention and treatment, pharmacologic treatment of hypertension in the obese, and the medical and surgical treatment of obesity in obese hypertensive patients. Obesity (2012) 相似文献
24.
A likelihood approach for comparing synonymous and nonsynonymous nucleotide substitution rates, with application to the chloroplast genome 总被引:29,自引:24,他引:5
A model of DNA sequence evolution applicable to coding regions is
presented. This represents the first evolutionary model that accounts for
dependencies among nucleotides within a codon. The model uses the codon, as
opposed to the nucleotide, as the unit of evolution, and is parameterized
in terms of synonymous and nonsynonymous nucleotide substitution rates. One
of the model's advantages over those used in methods for estimating
synonymous and nonsynonymous substitution rates is that it completely
corrects for multiple hits at a codon, rather than taking a parsimony
approach and considering only pathways of minimum change between homologous
codons. Likelihood-ratio versions of the relative-rate test are constructed
and applied to data from the complete chloroplast DNA sequences of Oryza
sativa, Nicotiana tabacum, and Marchantia polymorpha. Results of these
tests confirm previous findings that substitution rates in the chloroplast
genome are subject to both lineage-specific and locus-specific effects.
Additionally, the new tests suggest tha the rate heterogeneity is due
primarily to differences in nonsynonymous substitution rates. Simulations
help confirm previous suggestions that silent sites are saturated, leaving
no evidence of heterogeneity in synonymous substitution rates.
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Yulia Anita Muhammad Radifar Leonardus BS Kardono Muhammad Hanafi Enade P Istyastono 《Bioinformation》2012,8(19):901-906
Eugenol is an essential oil mainly found in the buds and leaves of clove (Syzygium aromaticum (L.) Merrill and Perry), which has
been reported to have activity on inhibition of cell proliferation and apoptosis induction in human MCF-7 breast cancer cells. This
biological activity is correlated to its activity as an estrogen receptor antagonist. In this article, we present the construction and
validation of structure-based virtual screening (SBVS) protocols to identify the potent estrogen receptor α (ER) antagonists. The
selected protocol, which gave acceptable enrichment factors as a virtual screening protocol, subsequently used to virtually screen
eugenol, its analogs and their dimers. Based on the virtual screening results, dimer eugenol of 4-[4-hydroxy-3-(prop-2-en-1-
yl)phenyl]-2-(prop-2-en-1-yl)phenol is recommended to be developed further in order to discover novel and potent ER antagonists. 相似文献
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The immunophenotype of HT29 human colon cancer cells implanted into severe combined immunodeficient mice was assessed in primary
tumours and their metastases in the lungs using an indirect immunohistochemical method. After primary tumours were surgically
removed, the metastases were given time to develop, thus paralleling the clinical situation. While vimentin was negative in
both primary and secondary tumours, E-cadherin was present as membrane-bound labelling in the primary tumours only. Whereas
the markers p53, MIB1, PCNA and CEA were consistently positive in both primary and metastatic tumours, CD44 variant 6 and
CA125 were negative in metastases but positive in the primary tumours. There was a significant increase in the percentage
of cells labelled for p53 in the primary tumours compared with the metastases. For the proliferation markers, there was no
significant difference in labelling between primary tumours and metastases for MIB1. Of the cytokeratins examined, CK 20 gave
the strongest and most consistent reaction in both primary and secondary tumours. The results indicate that, for certain immunohistochemical
markers, results are the same in both primary tumours and metastases. Hence, in these cases, antigens that are expressed on
the primary tumour as well as on the metastases can serve as target molecules for immunologically based forms of treatment
of metastases.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
30.