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101.
Ann-sphere order is a finite partially ordered set representable by containment ofn-spheres in Euclidean (n+1)-space. We present a sequence {P
i
} of ordered sets such that eachP
i
is ann-sphere order only forni; one consequence is that we are able to determine the dimension of a Euclidean space-time manifold from the finite suborders of its causality order.Research supported by ONR grant N00014 85-K-0769. 相似文献
102.
103.
104.
The multi-component isotherms for human insulin (HI) and desamido human insulin (dHI) over reversed phase packing (C18) and with 29.8% (w/w) ethanol-water as mobile phase have been determined experimentally. The isotherms of HI in ethanol-water differ from those obtained with the more commonly applied methanol-water and acetonitrile-water mobile phase, as described in this paper. The isotherm exhibits anti Langmuirian behavior and can be very well modeled by an anti Langmuir isotherm presented in this paper. The HI and dHI anti Langmuir isotherm are determined as: qHI = (8.4C(HI) + 3C(HI)CdHI)/(1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI) and qdHI = (11.4CdHI + 2C(HI)CdHI)/ (1 - 0.05C(HI) - 0.14CdHI + 0.04C(HI)CdHI) 相似文献
105.
微量元素对人体健康的影响 总被引:15,自引:2,他引:15
阐述了微量元素的生理作用以及对人体健康的影响和微量元素平衡的重要性,对临床医学及日常生活有一定的参考价值。 相似文献
106.
Treatment of (thd)H (thd=2,2,6,6-tetramethyl-3,5-heptandionate) with excess Os3(CO)12 in an autoclave at 180°C gives the formation of a brown metal chain complex [Os2(CO)5(thd)2]2 (1) and a yellow CO2 cluster complex [Os4(-H)(-CO2)(thd)(CO)13] (2) in low yields. Complex 2 was fully identified by a combination of spectroscopic methods and X-ray diffraction study, showing a unique CO2 ligand bridging a triosmium metal fragment, Os3(-H)(CO)10 and a monometallic osmium fragment, Os(CO)3(thd). Upon treatment of 1 with Me3NO at an elevated temperature, oxidation of the CO ligand occurred at the position trans to the unique CO2 ligand on the Os(CO)3(thd) fragment, giving the formation of a second CO2 cluster [Os4(-H)(-CO2)(thd)(CO)12(NCMe)] (3), which is stabilized by a weakly coordinated acetonitrile molecule. 相似文献
107.
Anna Michnik K. Michalik A. Kluczewska Zofia Drzazga 《Journal of Thermal Analysis and Calorimetry》2006,84(1):113-117
The thermal denaturation process of bovine and human
both fatty acid containing and fatty acid free albumins in aqueous solution
was studied by use of differential scanning calorimetry. Human serum albumins
were found to be more stable than their bovine counterparts. Fatty acid free
albumins were characterized as generally less stable, more susceptible to
aggregation, their unfolding endothermic transition was less cooperative and
with the smaller degree of reversibility. Deconvolution analysis with using
a non-two-state model with two component transitions showed essential differences
in the thermodynamic parameters between all studied albumins, particularly
regarding the high-temperature component transition. 相似文献
108.
High-level expression of soluble human β-defensin-2 fused with green fluorescent protein in Escherichia coli cell-free system 总被引:2,自引:0,他引:2
Human β-defensin-2 (hBD2), a small cationic peptide, exhibits a broad range of antimicrobial activity and does not acquire
any microbial resistance. To produce this uneasily detectable, degradable, and toxic polypeptide efficiently, an alternative
approach based on the Escherichia coli cell-free biosynthesis system was proposed. The approach implies that a polypeptide of interest is synthesized as a fusion
protein linked to a green fluorescent protein (GFP) through a cleavable spacer. With batch-mode operation, a significant amount
of hBD2 fused with GFP (0.25 mg/mL) can be expressed in this cell-free system. The productivity of the fusion protein can
be improved up to 1.2 mg/mL by employing a continuous-exchange cell-free system. Furthermore, the GFP moiety provides directly
visible and quantitative monitoring of the polypeptide synthesis, and the product is soluble and stable. This work will be
helpful in allowing the rapid and visible expression of other similar defensins using an in vitro cell-free system. 相似文献
109.
HIV infection leads to progressive alterations of humoral immune functions, including B-cell hyperplasia, hypergammaglobulinemia,
elevated autoantibody titers, a poor response to neoantigens and mitogens, polyclonal B-cell activation, monoclonal gammopathies,
and a significant deterioration of the antigen-specific humoral response. There is also an important isotypic imbalance of
the antibody (Ab) response in the systemic compartment and a profound modification of mucosal immune functions. These abnormalities
may contribute to disease progression and development of opportunistic infections, despite the presence of serum-neutralizing
anti-HIV Abs. Equally important are the abnormal selection mechanisms of the Ab repertoire that seem to be responsible for
B-cell clonal deletions. The VH3 gene family, which encodes for approx 50% of immunoglobulins expressed by peripheral B-cells from normal adults, is underrepresented
in human monoclonal antibodies to HIV-1 and in the peripheral B-cells of AIDS patients. These abnormalities, together with
features of germinal center alteration, could be responsible for the clonal elimination of a subset of B-cells, and could
contribute to HIV pathogenesis. 相似文献
110.
Study of the development of thermoresistance in human pancreatic carcinoma cell lines using proteome analysis 总被引:3,自引:0,他引:3
In order to find candidate proteins that are potentially associated with the thermoresistant phenotype in combination with drug resistance, we analyzed the differential protein expression in vitro in the human pancreatic cancer cell line EPP85-181-P and classical and atypical multidrug-resistant variants and their thermoresistant counterparts using proteomics. This study identifies sets of proteins that may lead to the development of thermoresistance. These results provide a fundamental basis to elucidate the molecular mechanism of thermoresistance and chemoresistance phenomena that may assist the therapy of inoperable cancers. 相似文献