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991.
Paraoxonase is an HDL-associated enzyme that plays a preventive role against oxidative stress, which is thought to contribute
to cancer development. PON1 activity varies widely among individuals, which is in part related to two common nonsynonymous
polymorphisms in the PON1 gene (Q192R and L55M). The polymorphisms in PON1 have been implicated in cancer risk. However, results
from the studies to date have been conflicting. To clarify the association, a meta-analysis was performed for 7,073 cases
and 9,520 controls from 25 published case–control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used
to assess the strength of the association. Significant associations between PON1-L55M but not Q192R polymorphism and total
cancer were observed from all the comparisons. In stratified analyses, PON1-55M allele was a risk factor for breast cancer.
Similarly, increased risk was observed for prostate cancer (OR = 1.18, 95% CI: 1.01–1.36, P
heterogeneity = 0.260) and Caucasian population (OR = 1.18, 95% CI: 1.02–1.38, P
heterogeneity = 0.1) of the LM genotype, compared with the LL genotype. For PON1-Q192R polymorphism, PON1-192R allele was a decreased risk
factor for cancer in the Asian group (RR vs QQ: OR = 0.61, 95% CI: 0.38–0.98, P
heterogeneity = 0.268; QR vs QQ: OR = 0.71, 95% CI: 0.52–0.96, P
heterogeneity = 0.130; RR + QR vs QQ: OR = 0.71, 95% CI: 0.53–0.95, P
heterogeneity = 0.135). Although some modest bias could not be eliminated, this meta-analysis suggests that the PON1-55M allele is a risk factor for the development of cancer, in particular for breast cancer. Future studies with larger sample
sizes are warranted to further evaluate these associations. 相似文献
992.
Peng Wang Yongzhong Xing Zhikang Li Sibin Yu 《Molecular breeding : new strategies in plant improvement》2012,29(4):903-913
To facilitate marker-assisted transfer of desirable genes for improvement of yield traits, we used a set of backcross recombinant
inbred lines (BRIL) derived from two elite parental lines, ‘Zhenshan97’ and ‘93-11’, to resolve a quantitative trait loci
(QTL) cluster for heading date and yield-related traits in rice. Four main-effect QTL (qHD6.1, qHD6.2, qHD7, and qHD8) and four epistatic QTL affecting heading date in the BRIL were detected in two experimental trials. The major QTL (qHD8) was confirmed in three heterogeneous inbred families (HIF) that segregated for this target region, and narrowed down to
a 20-kb segment in a large HIF-derived population. qHD8 was found to interact with qHD7 and had a pleiotropic effect responsible for heading date and yield components. To test usability of the identified QTL in
rice improvement, we further developed near-isogenic lines (NIL) containing one or more target genes by marker-assisted transfer
of ‘93-11’ alleles at qHD8, qHD7, and qHD6.1, and the GS3 gene for grain size into ‘Zhenshan97’. The pyramid line NIL(qHD8 + GS3) had higher yield potential, longer grains, and a more suitable heading date than ‘Zhenshan97’. Comparison of the NIL showed
existence of epistasis between alleles at different loci and background effect on qHD8, which are very important for pyramiding of desirable alleles at the target QTL. These results will be particularly useful
not only to understand the genetic basis of yield-related traits but also to improve the efficiency of marker-assisted selection
for favorable loci in rice breeding programs. 相似文献
993.
994.
Georgia E. Knauss Walter G. Joyce Tyler R. Lyson Dean Pearson 《Pal?ontologische Zeitschrift》2011,85(2):125-142
A nearly complete turtle shell from the Late Cretaceous (Maastrichtian) Hell Creek Formation of Slope County, North Dakota,
represents the most complete remains to date of a Mesozoic kinosternoid turtle and a new species, Hoplochelys clark nov. sp. The new taxon is diagnosable from other representatives of Hoplochelys by the plesiomorphic placement of the humeral/femoral sulcus behind the hyo/hypoplastral suture and the autapomorphic development
of an interrupted median (neural) keel. All six previously named Paleocene (Puercan and Torrejonian) representatives of Hoplochelys lack diagnostic characters and are synonymized as Hoplochelys crassa. A phylogenetic analysis reveals that Hoplochelys spp. and Agomphus pectoralis are most parsimoniously placed within Kinosternoidea along the phylogenetic stem of the extant Mesoamerican River Turtle
Dermatemys mawii, extending that taxon’s stem lineage from the early Eocene to the late Maastrichtian. The two primary crown lineages of Kinosternoidea
are thus known from the Mesozoic and split prior to the late Campanian. The presence of a thickened cruciform plastron, true
costiform processes, only three inframarginals, and the reduction of the medial contact of the abdominals are synapomorphies
of Chelydroidea, the clade formed by Chelydridae and Kinosternoidae. 相似文献
995.
The ethoxy chains of short ethoxy chain nonylphenol (NPEOav2.0, containing average 2.0 ethoxy units) were dehydrogenated by cell-free extracts from Ensifer sp. strain AS08 grown on a basal medium supplemented with NPEOav2.0. The reaction was coupled with the reduction in 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide and phenazine
methosulfate. The enzyme (NPEOav2.0 dehydrogenase; NPEO-DH) was purified to homogeneity with a yield of 20% and a 56-fold increase in specific activity. The
molecular mass of the native enzyme was 120 kDa, consisting of two identical monomer units (60 kDa). The gene encoding NPEO-DH
was cloned, which consisted of 1,659 bp, corresponding to a protein of 553 amino acid residues. The deduced amino acid sequence
agreed with the N-terminal amino acid sequence of the purified NPEO-DH. The presence of a flavin adenine dinucleotide (FAD)-binding
motif and glucose–methanol–choline (GMC) oxidoreductase signature motifs strongly suggested that the enzyme belongs to the
GMC oxidoreductase family. The protein exhibited homology (40–45% identity) with several polyethylene glycol dehydrogenases
(PEG-DHs) of this family, but the identity was lower than those (approximately 58%) among known PEG-DHs. The substrate-binding
domain was more hydrophobic compared with those of glucose oxidase and PEG-DHs. The recombinant protein had the same molecular
mass as the purified NPEO-DH and dehydrogenated PEG400-2000, NPEOav2.0 and its components, and NPEOav10, but only slight or no activity was found using diethylene glycol, triethylene glycol, and
PEG200.
English edition: The paper was edited by a native speaker through American Journal Experts (). 相似文献
996.
Qin Zhou Fan Zhao Ze-ping Lv Chen-guang Zheng Wei-dong Zheng Liang Sun Na-na Wang Shenghang Pang Fabiana Michelsen de Andrade Mian Fu Xiang-hua He Juan Hui Wen-yu Jiang Chu-yu Yang Xiao-hong Shi Xiao-quan Zhu Guo-fang Pang Yi-ge Yang Hai-qun Xie Wan-dong Zhang Cai-you Hu Ze Yang 《PloS one》2014,9(1)
Background
Previous association studies examining the relationship between the APOC1 polymorphism and susceptibility to Alzheimer’s disease (AD) have shown conflicting results, and it is not clear if an APOC1 variant acts as a genetic risk factor in AD etiology across multiple populations.Methods
To confirm the risk association between APOC1 and AD, we designed a case-control study and also performed a meta-analysis of previously published studies.Results
Seventy-nine patients with AD and one hundred fifty-six unrelated controls were included in case-control study. No association was found between the variation of APOC1 and AD in stage 1 of our study. However, our meta-analysis pooled a total of 2092 AD patients and 2685 controls. The APOC1 rs11568822 polymorphism was associated with increased AD risk in Caucasians, Asians and Caribbean Hispanics, but not in African Americans. APOE ε4 carriers harboring the APOC1 insertion allele, were more prevalent in AD patients than controls (χ2 = 119.46, OR = 2.79, 95% CI = 2.31–3.36, P<0.01).Conclusions
The APOC1 insertion allele, in combination with APOE ε4, likely serves as a potential risk factor for developing AD. 相似文献997.
This paper deals with the botanical study of a family funerary enclosure located in the Porta Nocera necropolis in Pompeii
(southwestern Italy). This study is part of a Franco-Italian programme investigating Roman funerary rituals. The choice of
the context was due to the exceptional preservation of the archaeological features, which offered the opportunity to observe
the remains of the proceedings which took place in a funerary enclosure in great detail. An adequate methodology had to be
developed and a 3D recording of every single artefact or ecofact has been made. Both ground surfaces and graves provided botanical
results. Those from the ground surfaces consisted mainly of fruit offering residues (especially fig and grape), while a much
wider range of species was observed in the tombs, including cereals, pulses, other kinds of fruits, weeds and bread/pastry.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
998.
Bengt Steen 《The International Journal of Life Cycle Assessment》2007,12(2):103-108
Goal, Scope and Background The life cycles of many products including textiles contain chemicals for which process flow data are not known or are too
time consuming to collect. Although each chemical may not contribute significantly to the LCA results of the product, which
might justify excluding them, but together their contribution could be significant. Similarly, rough estimates of the process
flows for the production of a single chemical may be very uncertain and considered meaningless, while the estimates of the
cumulative data of process flows for several chemicals may be less uncertain and be a meaningful contribution to the quality
of the LCA results. There are methods for estimation of process flows for different types of products, with varying demands
regarding input data and time and with varying accuracy of the results. This work contributes to the available methods, focusing
on simple estimations for production of chemical substances. The goal was to create a fast method for estimation of emissions,
resource and energy flows (process flows) for the production of chemicals, based on easily available data on the properties
of the chemicals. The process flows investigated were limited to those normally associated with process industries and contributing
most to depletion of resources, to global warming, acidification, eutrophication and photochemical ozone production, i.e.
use of energy, crude oil, coal, natural gas, uranium in ore and emissions of CO2, SOx, NOx, NMVOC, methane, BOD, COD and total
N. Toxic substances were excluded, since toxic emissions are substance specific and cannot be included in a generalization.
Method Available data for the process flows for the production of chemicals of mainly fossil origin were correlated to properties
of chemicals such as amount of carbon in the molecule, heat of formation and average number of chemical reaction steps in
the production. The production procedures were found in readily available literature. Up to about six reaction steps were
evaluated in the correlation study. The variations in the process flows among the chemicals studied were calculated.
Results and Discussion There were weak correlations between average number of chemical reaction steps in the production and energy use, COD measured
in water emissions, and SOx and NOx emissions to air. For the remaining properties of chemicals and process flows, there were
only weak correlations for share of double bonding in the molecule if only molecules containing double bondings were included.
Conclusions The precision in estimation of the process flows increases non-significantly when adding information on the number of reaction
steps or share of double bonding for chemicals containing double bonding is added.
Recommendations and Outlook It seems reasonable to start with a simple grouping method to estimate the process flows for the production of a chemical
of fossil origin. Further investigations might investigate whether there is a correlation between process flows and the costs
of chemicals, and further study the correlations between process flows and share of double bonding for chemicals containing
double bondings. 相似文献
999.
Images of human erythrocytes from a healthy donor were recorded under differential interference contrast (DIC) microscopy;
they were acquired rapidly (~336 Hz) and the intensity of the centermost pixel of each cell was recorded for ~60 s (20,000
values). Various techniques were used to analyze the data, including detrended fluctuation analysis (DFA) and multiscale entropy
(MSE); however, power spectrum analysis was deemed the most appropriate for metrifying and comparing results. This analysis
was used to compare cells from young and old populations, and after perturbing normal conditions, with changes in temperature,
adenosine triphosphate (ATP) concentration (using NaF, an inhibitor of glycolysis, and α-toxin, a pore-forming molecule used
to permeabilize red cells to ATP), and water transport rates [using glycerol, and p-chloromercuriphenylsulfonic acid (pCMBS) to inhibit aquaporins, AQPs]. There were measurable differences in the membrane
fluctuation characteristics in populations of young and old cells, but there was no significant change in the flickering time
series on changing the temperature of an individual cell, by depleting it of ATP, or by competing with the minor water exchange
pathway via AQP3 using glycerol. However, pCMBS, which inhibits AQP1, the major water exchange pathway, inhibited flickering
in all cells, and yet it was restored by the membrane intercalating species dibutyl phthalate (DBP). We developed a computer
model to simulate acquired displacement spectral time courses and to evaluate various methods of data analysis, and showed
how the flexibility of the membrane, as defined in the model, affects the flickering time course. 相似文献
1000.
Ali Zohaib Muhammad Saqib Muhammad Ammar Athar Jing Chen Awais-ur-Rahman Sial Saeed Khan Zeeshan Taj Halima Sadia Usman Tahir Muhammad Haleem Tayyab Muhammad Asif Qureshi Muhammad Khalid Mansoor Muhammad Ahsan Naeem Bing-Jie Hu Bilal Ahmed Khan Ikram Din Ujjan Bei Li Wei Zhang Yun Luo Yan Zhu Cecilia Waruhiu Iahtasham Khan Xing-Lou Yang Muhammad Sohail Sajid Victor Max Corman Bing Yan Zheng-Li Shi 《中国病毒学》2018,33(5):410-417
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels. 相似文献