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71.
Shen M Zhang L Lee KM Vermeulen R Hosgood HD Li G Yin S Rothman N Chanock S Smith MT Lan Q 《Experimental & molecular medicine》2011,43(6):374-378
Benzene, a recognized hematotoxicant and carcinogen, can damage the human immune system. We studied the association between single nucleotide polymorphisms (SNPs) in genes involved in innate immunity and benzene hematotoxicity in a cross-sectional study of workers exposed to benzene (250 workers and 140 controls). A total of 1,236 tag SNPs in 149 gene regions of six pathways were included in the analysis. Six gene regions were significant for their association with white blood cell (WBC) counts (MBP, VCAM1, ALOX5, MPO, RAC2, and CRP) based on gene-region (P<0.05) and SNP analyses (FDR<0.05). VCAM1 rs3176867, ALOX5 rs7099684, and MPO rs2071409 were the three most significant SNPs. They showed similar effects on WBC subtypes, especially granulocytes, lymphocytes, and monocytes. A 3-SNP block in ALOXE3 (rs7215658, rs9892383, and rs3027208) showed a global association (omnibus P = 0.0008) with WBCs even though the three SNPs were not significant individually. Our study suggests that polymorphisms in innate immunity genes may play a role in benzene-induced hematotoxicity; however, independent replication is necessary. 相似文献
72.
Kumari H Kline SR Schuster NJ Atwood JL 《Chemical communications (Cambridge, England)》2011,47(45):12298-12300
The stability of copper-seamed C-alkylpyrogallol[4]arene hexamers with varying chain lengths in solution has been studied using small-angle neutron scattering (SANS). The progression in diameter of spherical capsules with increasing alkyl chain lengths of copper-seamed hexamers in solution suggests both robustness as well as a close correlation between the solid phase and solution phase structures. 相似文献
73.
Imaz I Rubio-Martínez M An J Solé-Font I Rosi NL Maspoch D 《Chemical communications (Cambridge, England)》2011,47(26):7287-7302
Biomolecules are the building blocks of life. Nature has evolved countless biomolecules that show promise for bridging metal ions. These molecules have emerged as an excellent source of biocompatible building blocks that can be used to design Metal-Biomolecule Frameworks (MBioFs). This feature article highlights the advances in the synthesis of this class of MOFs. Special emphasis is provided on the crystal structures of these materials, their miniaturization to the submicron length scale, and their new potential storage, catalytic, and biomedical applications. 相似文献
74.
The origin of long homochiral biopolymers in living systems has recently been the focus of intense research. In one particular research line, scientists studied, experimentally and theoretically, chiral amplification obtained during peptide formation by polymerization of amino acid building blocks. It was suggested that processes leading to temporal or spatial separation, and thus, to the growth of homochiral polymers at the expense of their heterochiral counterparts, can explain the chirality observed in larger molecules. We introduce a simple model and stochastic simulation for the polymerization of amino acids and β-sheet formation, showing the crucial effects of the β sheets on the distributions of peptide lengths. When chiral affinities are included, racemic β sheets of alternating homochiral strands lead to the formation of chiral peptides, the isotacticity of which increases with length, consistent with previous experimental results in aqueous solutions. The tendency to form isotactic peptides is shown for both initially racemic and initially nonracemic systems, as well as for closed and open systems. We suggest that these or similar mechanisms may explain the origin of chiroselectivity in prebiotic environments. 相似文献
75.
Jewell Nathaniel; Denier James P. 《The Quarterly Journal of Mechanics and Applied Mathematics》2006,59(4):651-673
This paper considers the decay of Poiseuille flow within a suddenlyblocked pipe. For small to moderate times the flow is shownto consist of an inviscid core flow coupled with a boundarylayer at the pipe wall. A small-time asymptotic solution isdeveloped and it is shown that this solution is valid for timesup to the point at which the boundary layer fills the wholepipe. A small-time composite solution is used to initiate anumerical marching procedure which overcomes the small-timesingularity that arises in the flow and so allows us to describethe ultimate decay of the flow within a blocked pipe. The stabilityof this flow is then considered using both a quasi-steady approximationand a transient-growth analysis based upon marching solutionsof the linearized NavierStokes equations. Our transientstability analysis predicts a critical Reynolds number, fortransition to turbulence, in the range 970 < Re < 1370. 相似文献
76.
W. J. King E. D. Campbell W. B. Hurley O. L. Maag C. H. Mc Collam U. S. Steel Corporation J. Kassler A. Chilesotti J. Sand O. Burger Johanna Maas A. Rosenheim G. Garfunkel C. Krauskopf C. E. Swartz G. Spurge S. L. Malowan E. Wendehorst H. ter Meulen Dorothy Hall K. Agte H. Becker-Rose und G. Heyne 《Fresenius' Journal of Analytical Chemistry》1928,74(3-4):122-131
Ohne Zusammenfassung 相似文献
77.
78.
Nathaniel Chafee 《Journal of Differential Equations》1974,15(3):522-540
We consider a parabolic partial differential equation ut = uxx + f(u), where ? ∞ < x < + ∞ and 0 < t < + ∞. Under suitable hypotheses pertaining to f, we exhibit a class of initial data φ(x), ? ∞ < x < + ∞, for which the corresponding solutions u(x, t) approach zero as t → + ∞. This convergence is uniform with respect to x on any compact subinterval of the real axis. 相似文献
79.
80.
Heinz Nadig Urs Squin Richard H. Bunge Timothy R. Hurley David B. Murphey James C. French 《Helvetica chimica acta》1985,68(4):953-957
A novel antibiotic, PD 121,222, was isolated from a complex of pluramycin-like compounds containing mostly kidamycin and neopluramycin. Spectral analyses showed that this compound is the 14,16-dihydroxy analog of rubiflavin A. 相似文献