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81.
Rothman DM Petersson EJ Vázquez ME Brandt GS Dougherty DA Imperiali B 《Journal of the American Chemical Society》2005,127(3):846-847
We present the chemical and biological synthesis of caged phosphoproteins using the in vitro nonsense codon suppression methodology. Specifically, phosphoamino acid analogues of serine, threonine, and tyrosine with a single photocleavable o-nitrophenylethyl caging group were synthesized as the amino acyl tRNA adducts for insertion into full-length proteins. For this purpose, a novel phosphitylating agent was developed. The successful incorporation of these bulky and charged amino acids into the alpha-subunit of the nicotinic acetyl choline receptor (nAChR) and the vasodilator-stimulated phosphoprotein (VASP) using an in vitro translation system is reported. 相似文献
82.
83.
Deborah Evelyn 《The Journal of the Operational Research Society》1982,33(2):201-202
84.
Thomas Bauch Andrea Sanders Charles V. Magatti Paul Waterman Deborah Judelson Warren P. Giering 《Journal of organometallic chemistry》1975,99(2):269-279
The reactions between cis- and trans-1,2-dibromo- or 1,2-diidobenzocyclobutene and NaFe(CO)2Cp (NaFp) were investigated. The mechanism of formation of 1,2-bis(cyclopentadienyldicarbonyliron)benzocyclobutene (I) and 1-(cyclopentadienyldicarbonyliron)benzocyclobutene (II) is thought to involve initial formation of benzocyclobutadiene, addition of a Fp radical to benzocyclobutadiene and subsequent addition of a second Fp radical to form I, or hydrogen abstraction from FpH to form II. 相似文献
85.
Aldridge S Kays DL Al-Fawaz A Jones KM Horton PN Hursthouse MB Harrington RW Clegg W 《Chemical communications (Cambridge, England)》2006,(24):2578-2580
The reaction of (eta(5)-C5H5)Fe(CO)2B(C6F5)2 with CO has been shown to proceed via ligand substitution at the metal with accompanying transfer of the boryl fragment (via C-H insertion) to the Cp ring, thereby generating the zwitterion [eta(5)-C5H4B(C6F5)2H]Fe(CO)3 in quantitative yield. 相似文献
86.
87.
An exactly solvable model of multisite condensed-phase vibrational relaxation was studied in Paper I (Peter, S.; Evans, D. G.; Coalson, R. D. J. Phys. Chem. B 2006, 110, 18758.), where it was shown that long-time steady-state site populations of a degenerate N-level system are not equal (hence, they are non-Boltzmann) and depend on the initial preparation of the system and the number of sites that it comprises. Here we consider a generalization of the model to the case of a nondegenerate three-level system coupled to a high-dimensional bath: such a model system has direct relevance to a large class of donor-bridge-acceptor electron transfer processes. Because the quantum dynamics of this system cannot be computed analytically, we compare numerically exact path integral calculations to the predictions of second-order time-local relaxation theory. For modest system-bath coupling strengths, the two sets of results are in excellent agreement. They show that non-Boltzmann long-time steady-state site populations are obtained when the level splitting is small but nonzero, whereas at larger values of the system bias (asymmetry) these populations become Boltzmann distributed. 相似文献
88.
Let M be a 3-connected binary matroid and let n be an integer exceeding 2. Ding, Oporowski, Oxley, and Vertigan proved that there is an integer f(n) so that if |E(M)|>f(n), then M has a minor isomorphic to one of the rank-n wheel, the rank-n tipless binary spike, or the cycle or bond matroid of K3,n. This result was recently extended by Chun, Oxley, and Whittle to show that there is an integer g(n) so that if |E(M)|>g(n) and x∈E(M), then x is an element of a minor of M isomorphic to one of the rank-n wheel, the rank-n binary spike with a tip and a cotip, or the cycle or bond matroid of K1,1,1,n. In this paper, we prove that, for each i in {2,3}, there is an integer hi(n) so that if |E(M)|>hi(n) and Z is an i-element rank-2 subset of M, then M has a minor from the last list whose ground set contains Z. 相似文献
89.
Alessio Alesci Andrea Salvo Eugenia Rita Lauriano Teresa Gervasi Deborah Palombieri Maurizio Bruno 《Natural product research》2015,29(12):1122-1126
The effect of astaxanthin (3,3′-dihydroxy-s-carotene-4,4′-dione) on alcohol-induced morphological changes in Carassius auratus, as an experimental model, was determined. The yeast Phaffia rhodozyma was used as a source of astaxanthin. The animals were divided into three groups for 30 days: one group was treated with ethanol at a dose of 1.5% mixed in water, the second one with EtOH 1.5% and food enriched with astaxanthin from P. rhodozyma, and the third was a control group. After a sufficient experimental period, the samples were processed using light microscopy and evaluated by histomorphological and histochemical staining, and the data were supported by immunohistochemical analysis, using a wide range of antibodies, such as calbindin, vimentin and alpha-smooth muscle actin. The results show that the alcoholic damage in the kidney led to hypoxia. In contrast, the group fed with astaxanthin from P. rhodozyma showed a normal morphological picture, with better glomeruli organisation and the presence of the area of filtration. Furthermore, the immunohistochemistry has confirmed these results. 相似文献
90.
Deborah Bromfield Lee 《Green Chemistry Letters and Reviews》2019,12(2):107-116
ABSTRACTGreen Chemistry principles can be used to re-cast traditional Organic chemistry experiments into more guided-inquiry based experiments. Inquiry questions related to green chemistry principles and metrics have been incorporated into our laboratory for the development of more guided-inquiry based experiments. Re-casting traditional experiments provides time for guided-inquiry by allowing students to evaluate reaction conditions and wastefulness of reactions. This includes evaluating solvent choices, heating methods, use of renewal materials, and contemplating reactants and products impacts on human health and environment. Students examine the changes as it pertains to green chemistry, the success of the reaction and the potential impacts on the mechanism. Involving students in these discoveries rooted in a guiding question made the Organic experiments guided-inquiry. Students were surveyed about their exposure to green chemistry and guided-inquiry based labs. Examples of some of the re-casted experiments, excerpts from student reports, and student impressions of the theme are presented. 相似文献