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排序方式: 共有816条查询结果,搜索用时 265 毫秒
71.
72.
Serena P. Koenig Alexandra Bornstein Karine Severe Elizabeth Fox Jessy G. Dévieux Patrice Severe Patrice Joseph Adias Marcelin Dgndy Alexandre Bright Ngoc Pham Pierre Cremieux Jean William Pape 《PloS one》2015,10(11)
Objective
We assessed the association between gender and mortality on antiretroviral therapy (ART) using identical models with and without sex-specific categories for weight and hemoglobin.Design
Cohort study of adult patients on ART.Setting
GHESKIO Clinic in Port-au-Prince, Haiti.Participants
4,717 ART-naïve adult patients consecutively enrolled on ART at GHESKIO from 2003 to 2008.Main Outcome Measure
Mortality on ART; multivariable analyses were conducted with and without sex-specific categories for weight and hemoglobin.Results
In Haiti, male gender was associated with mortality (OR 1.61; 95% CI: 1.30–2.00) in multivariable analyses with hemoglobin and weight included as control variables, but not when sex-specific interactions with hemoglobin and weight were used.Conclusions
If sex-specific categories are omitted, multivariable analyses indicate a higher risk of mortality for males vs. females of the same weight and hemoglobin. However, because males have higher normal values for weight and hemoglobin, the males in this comparison would generally have poorer health status than the females. This may explain why gender differences in mortality are sometimes observed after controlling for differences in baseline variables when gender-specific interactions with weight and hemoglobin are omitted. 相似文献73.
Tess V. Clendenen Justin Rendleman Wenzhen Ge Karen L. Koenig Isaac Wirgin Diane Currie Roy E. Shore Tomas Kirchhoff Anne Zeleniuch-Jacquotte 《PloS one》2015,10(8)
Background
Large epidemiologic studies have the potential to make valuable contributions to the assessment of gene-environment interactions because they prospectively collected detailed exposure data. Some of these studies, however, have only serum or plasma samples as a low quantity source of DNA.Methods
We examined whether DNA isolated from serum can be used to reliably and accurately genotype single nucleotide polymorphisms (SNPs) using Sequenom multiplex SNP genotyping technology. We genotyped 81 SNPs using samples from 158 participants in the NYU Women’s Health Study. Each participant had DNA from serum and at least one paired DNA sample isolated from a high quality source of DNA, i.e. clots and/or cell precipitates, for comparison.Results
We observed that 60 of the 81 SNPs (74%) had high call frequencies (≥95%) using DNA from serum, only slightly lower than the 85% of SNPs with high call frequencies in DNA from clots or cell precipitates. Of the 57 SNPs with high call frequencies for serum, clot, and cell precipitate DNA, 54 (95%) had highly concordant (>98%) genotype calls across all three sample types. High purity was not a critical factor to successful genotyping.Conclusions
Our results suggest that this multiplex SNP genotyping method can be used reliably on DNA from serum in large-scale epidemiologic studies. 相似文献74.
PGE2 plays an important role in a broad spectrum of physiological and pathological processes mediated through a membrane-bound G protein-coupled receptor (GPCR) called EP receptor. In mammals, four subtypes of EP receptor (EP 1-4) are identified and each of them functions through different signal transduction pathways. Orthologous EP receptors have also been identified in other non-mammalian species, such as chicken and zebrafish. EP4 is the only identified PGE2 receptor to date in Atlantic salmon but its tissue distribution and function have not been studied in any detail. In this study, we first sequenced EP4 receptor in different tissues and found that the presence of the 3nt deletion in the 5’ untranslated region was accompanied by silent mutation at nt 668. While attempting to amplify the same sequence in TO cells (an Atlantic salmon macrophage-like cell line), we failed to obtain the full-length product. Further investigation revealed different isoform of EP4 receptor in TO cells and we subsequently documented its presence in different Atlantic salmon tissues. These two isoforms of EP4 receptor share high homology in their first half of sequence but differ in the second half part with several deletion segments though the final length of coding sequence is the same for two isoforms. We further studied the immunomodulation effect of PGE2 in TO cells and found that PGE2 inhibited the induction of CXCL-10, CCL-4, IL-8 and IL-1β genes expression in a time dependent manner and without cAMP upregulation. 相似文献
75.
The current research applied a mid-level evolutionary theory that has been successfully employed across numerous animal species—life
history theory—in an attempt to understand the Dark Triad personality trait cluster (narcissism, psychopathy, and Machiavellianism).
In Study 1 (N = 246), a measure of life history strategy was correlated with psychopathy, but unexpectedly with neither Machiavellianism
nor narcissism. Study 2 (N = 321) replicated this overall pattern of results using longer, traditional measures of the Dark Triad traits and alternative,
future-discounting indicators of life history strategy (a smaller-sooner, larger-later monetary dilemma and self-reported
risk-taking behaviors). Additional findings suggested two sources of shared variance across the Dark Triad traits: confidence
in predicting future outcomes and openness to short-term mating. 相似文献
76.
77.
WOX4 Promotes Procambial Development 总被引:1,自引:0,他引:1
Jiabing Ji Josh Strable Rena Shimizu Daniel Koenig Neelima Sinha Michael J. Scanlon 《Plant physiology》2010,152(3):1346-1356
78.
79.
Koenig A Roegler C Lange K Daiber A Glusa E Lehmann J 《Bioorganic & medicinal chemistry letters》2007,17(21):5881-5885
The vasoactive properties of 14 organic mononitrates were investigated in vitro using PGF(2alpha)-precontracted porcine pulmonary arteries. A surprisingly wide range of vasorelaxant potencies was observed (pD(2): 3.36-7.50). Activities showed to be highly sensitive to the molecular structure and the substituents at the molecular carrier of the nitrate group. A correlation between lipophilicity and vasorelaxant potency could not be recognized. 2-Nitrooxyethylammoniumnitrate (1) was found to be slightly superior to the high potency trinitrate GTN. 相似文献
80.
Idell S Allen T Chen S Koenig K Mazar A Azghani A 《American journal of physiology. Lung cellular and molecular physiology》2007,293(1):L25-L32
High levels of adenosine can be measured from the lungs of asthmatics, and it is well recognized that aerosolized 5'AMP, the precursor of adenosine, elicits robust bronchoconstriction in patients with this disease. Characterization of mice with elevated adenosine levels secondary to the loss of adenosine deaminase (ADA) expression, the primary metabolic enzyme for adenosine, further support a role for this ubiquitous mediator in the pathogenesis of asthma. To begin to identify pathways by which adenosine can alter airway tone, we examined adenosine-induced bronchoconstriction in four mouse lines, each lacking one of the receptors for this nucleoside. We show, using direct measures of airway mechanics, that adenosine can increase airway resistance and that this increase in resistance is mediated by binding the A(1) receptor. Further examination of this response using pharmacologically, surgically, and genetically manipulated mice supports a model in which adenosine-induced bronchoconstriction occurs indirectly through the activation of sensory neurons. 相似文献