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21.
Bakker MF Verstappen SM Welsing PM Jacobs JW Jahangier ZN van der Veen MJ Bijlsma JW Lafeber FP;Utrecht Arthritis Cohort study group 《Arthritis research & therapy》2011,13(3):R70
Introduction
The aim of this study was to investigate whether serum biomarker levels of C2C, C1,2C, CS846, and CPII can predict the long-term course of disease activity and radiographic progression early in the disease course of rheumatoid arthritis (RA). 相似文献22.
We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
相似文献
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25.
MM El-Shazly El Elzayat IIA El-Sebeay YA Edmardash MM Soliman 《African Journal of Aquatic Science》2016,41(3):289-296
Manzala Lake, as one of the main Egyptian wetland ecosystems, is facing risks of pollution. An in vitro cytotoxicity test using a mammalian cell line was employed to determine the toxicity of multiple pollutants in the water and Tilapia zillii fish sampled from the lake. The concentrations of seven polychlorinated dibenzo-p-dioxins and ten polychlorinated dibenzofurans were investigated in water and muscle of the fish in 2014. Cytotoxicity testing showed that the percentage inhibition of cell viability in the studied sites ranged between 56.16% and 83.22%. Dioxin analysis indicated that the average concentrations of 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, 1,2,3,4,7,8-hexachlorodibenzofuran, 1,2,3,4,6,7,8-heptachlorodibenzofuran and 1,2,3,4,6,7,8,9-octachlorodibenzofuran were higher than the toxic equivalence quotients (TEQs) set by the World Health Organization (WHO) in all water and fish muscle samples; however, the average concentration of 2,3,7,8-tetrachlorodibenzofuran was higher only in fish muscle samples. The bioaccumulation factor (BAF) ranged dramatically between 2 and 58.5 for the detected dioxins. Adverse human health effects through the consumption of fish are not expected, because dioxin levels in fish muscle are deemed safe for human consumption. Implementation of a strategic multidisciplinary action plan is strongly recommended to sustain this delta wetland ecosystem. 相似文献
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In the companion paper (Holmquist et al. 1988), we concluded that there is
no agreement on either the correct branching order or differential rates of
evolution among the higher primates, and we examined in depth why this
uncertainty in the evolutionary understanding of our closest living
relatives persists. Recently, Lake developed two novel methods, based on
group properties of transition and transversion operators, that (a) permit,
in principle, objective resolution of problems of the above type and (b)
attach a statistical significance level to the conclusions drawn. In the
present paper, we develop formulas for using these two methods in tandem
and apply them to study transversion differences in (1) nuclear DNA for a
7-kb segment of the psi eta-globin locus and a 3-kb intergenic region
between the psi beta- and delta- globin loci and (2) mitochondrial DNA for
the 896-bp fragment of Brown et al. Although each of these nucleotide
sequence regions has its characteristic tempo and mode of evolution, the
nuclear and mitochondrial data together, comprising a total of 10,939 base
positions, support a Homo/Pan clade at the 97% confidence level. If we
calibrate the divergence point for humans and chimpanzees at 5 Myr,
consideration of the transversion branch lengths for the combined nuclear
data indicates that the gorilla lineage branched off 600,000- 900,000 years
prior to that, although the 2 sigma sampling errors do not preclude either
a temporal trifurcation for the three species or a considerably more
ancient branch point for the gorilla. To resolve the length of this central
branch to a relative accuracy of 25% and 30% will require a factor of 16
and nine times more data, respectively-- i.e., in excess of 100,000
homologous nucleotides for each of the four primates. For the nuclear
genes, heterogeneity in evolutionary rates between different parts of the
genome is mostly restricted to the human lineage for these two segments.
The lineage leading to chimpanzees has evolved 0.4 (3-kb fragment) to 3.5
(7-kb segment) times as rapidly as the lineage leading to humans, and that
leading to the gorilla has evolved approximately one-fifth to one-half as
rapidly as that leading to chimpanzees. Thus, even local molecular clocks
can "tick" badly. As significant is the fact that virtually contiguous
parts of the genome tick at markedly different rates.(ABSTRACT TRUNCATED AT
400 WORDS)
相似文献
28.
Jana Milucka Mathias Kirf Lu Lu Andreas Krupke Phyllis Lam Sten Littmann Marcel MM Kuypers Carsten J Schubert 《The ISME journal》2015,9(9):1991-2002
Freshwater lakes represent large methane sources that, in contrast to the Ocean, significantly contribute to non-anthropogenic methane emissions to the atmosphere. Particularly mixed lakes are major methane emitters, while permanently and seasonally stratified lakes with anoxic bottom waters are often characterized by strongly reduced methane emissions. The causes for this reduced methane flux from anoxic lake waters are not fully understood. Here we identified the microorganisms and processes responsible for the near complete consumption of methane in the anoxic waters of a permanently stratified lake, Lago di Cadagno. Interestingly, known anaerobic methanotrophs could not be detected in these waters. Instead, we found abundant gamma-proteobacterial aerobic methane-oxidizing bacteria active in the anoxic waters. In vitro incubations revealed that, among all the tested potential electron acceptors, only the addition of oxygen enhanced the rates of methane oxidation. An equally pronounced stimulation was also observed when the anoxic water samples were incubated in the light. Our combined results from molecular, biogeochemical and single-cell analyses indicate that methane removal at the anoxic chemocline of Lago di Cadagno is due to true aerobic oxidation of methane fuelled by in situ oxygen production by photosynthetic algae. A similar mechanism could be active in seasonally stratified lakes and marine basins such as the Black Sea, where light penetrates to the anoxic chemocline. Given the widespread occurrence of seasonally stratified anoxic lakes, aerobic methane oxidation coupled to oxygenic photosynthesis might have an important but so far neglected role in methane emissions from lakes. 相似文献
29.
Sans résuméI. Analyse électrocapillaire des matières colorantes. Rev. gén. Mat. Col. 1926 Vol. 30 pp 34–45II. Phénomènes électrocapillaires et le problème du cancer. Arch. Med. Exper. 1926 Vol. I p 381III. Phénomènes électrocapillaires et l'antagonismes microbiens. Bol. Istituto Sier. Milano 1927 Vol. VI p 313. 相似文献
30.