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21.
Mackiewicz P Kowalczuk M Mackiewicz D Nowicka A Dudkiewicz M Laszkiewicz A Dudek MR Cebrat S 《Yeast (Chichester, England)》2002,19(7):619-629
We have compared the results of estimations of the total number of protein-coding genes in the Saccharomyces cerevisiae genome, which have been obtained by many laboratories since the yeast genome sequence was published in 1996. We propose that there are 5300-5400 genes in the genome. This makes the first estimation of the number of intronless ORFs longer than 100 codons, based on the features of the set of genes with phenotypes known in 1997 to be correct. This estimation assumed that the set of the first 2300 genes with known phenotypes was representative for the whole set of protein-coding genes in the genome. The same method used in this paper for the approximation of the total number of protein-coding sequences among more than 40 000 ORFs longer than 20 codons gives a result that is only slightly higher. This suggests that there are still some non-coding ORFs in the databases and a few dozen small ORFs, not yet annotated, which probably code for proteins. 相似文献
22.
Poly(N-isopropylacrylamide), NIPA, thermoresponsive hydrogels with well-defined concentrations of an electroactive probe, 1,1'-ferrocenedimethanol, Fc(MeOH)2, were prepared. The discontinuous reversible volume phase transition of such gels occurs at 32 +/- 1 degrees C and results in a release of approximately 93% of the solution from the polymeric network. Transport of Fc(MeOH)2 in both swollen and collapsed gels was studied using steady-state voltammetry and chronoamperometry at platinum microelectrodes. The diffusion coefficient of Fc(MeOH)2 in collapsed gels was approximately 2 orders of magnitude smaller than that in swollen gels. UV/vis spectroscopic studies showed that for 3.0% NIPA gel, the concentration of Fc(MeOH)2 in the collapsed phase was approximately 6 times higher than that in released solution and 4.5 times higher than in the original swollen gel. 相似文献
23.
Lewera A Miecznikowski K Chojak M Makowski O Golimowski J Kulesza PJ 《Analytical chemistry》2004,76(10):2694-2699
A novel electroanalytical approach is proposed here, and it is demonstrated with the direct and simultaneous determination of two unknowns: the concentration of redox sites and the apparent diffusion coefficient for charge propagation in a single crystal of dodecatungstophosphoric acid. This Keggin-type polyoxometalate serves as a model bulk redox conducting inorganic material for solid-state voltammetry. The system has been investigated using an ultramicrodisk working electrode in the absence of external liquid supporting electrolyte. The analytical method requires numerical solution of the combination of two equations in which the first one describes current (or charge) in a well-defined (either spherical or linear) diffusional regime and the second general equation describes chronoamperometric (or normal pulse voltammetric current) under mixed (linear-spherical) conditions. The iterative approach is based on successive approximations through calculation and minimizing the least-squares error function. The method is fairly universal, and in principle, it can be extended to the investigation of other bulk systems including sol-gel processed materials, redox melts, and solutions on condition that they are electroactive and well behaved, they contain redox centers at sufficiently high level, and a number of electrons for the redox reaction considered is known. 相似文献
24.
Malgorzata Nogala-Kalucka Magdalena Rudzinska Ryszard Zadernowski Aleksander Siger Inga Krzyzostaniak 《Journal of the American Oil Chemists' Society》2010,87(12):1481-1487
The lipophilic and hydrophilic antioxidants were evaluated in eight plants: safflower (Carthamus tinctorius), viper’s bugloss (Echium vulgare), quince (Cydonia vulgaris), evening primrose (Oenothera biennis), rose mosqueta (Rosa affinis rubiginosa), black seed (Nigella sativa), sea buckthorn (Hippophae rhamnoides) and borage (Borago officinales). The highest amounts of tocopherols were contained in seeds of borage and sea buckthorn (66.9 mg/100 g and 45.9 mg/100 g,
respectively). The sea buckthorn seed lipids had the highest amount of total sterols (10.4 mg/g of lipids). The predominant
form was campesterol. Sitosterol was the major sterol in the lipids of other tested seeds. The content of phenolic compounds
ranged from 736.5 mg/100 g dry matter (d.m.) (evening primrose) to 74.8 mg/100 g d.m. (safflower). The highest antioxidant
activity, expressed in % scavenged DPPH· free radicals, was observed for evening primrose (91.2%), while the lowest for safflower
(36.2%). The correlation coefficient between the level of phenolic compounds and antioxidant activity was 0.53. 相似文献
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We report a substantial reduction of frequency chirp of a single-mode laser-pumped zigzag dye laser. A linear optical cavity using counterpropagating orthogonally polarized waves was injection-seeded at 568 mn and operated with a laser output of about 1 J. The chirp was controlled by an intracavity Pockels cell that was configured to add optical density at a rate which counterbalanced the decrease in optical density due to dye-solvent heating during the ~1-μs laser pulse. Heterodyne measurements were used to determine that the bandwidth was near the transform limit and chirp rate of ~1 MHz/μs. The beam quality of the laser was measured at 10 Hz as 1.7 XDL 相似文献
28.
Katarzyna M. Terlikowska Anna M. Witkowska Malgorzata E. Zujko Bozena Dobrzycka Slawomir J. Terlikowski 《International journal of molecular sciences》2014,15(12):21703-21722
Recent findings on the molecular basis of ovarian cancer development and progression create new opportunities to develop anticancer medications that would affect specific metabolic pathways and decrease side systemic toxicity of conventional treatment. Among new possibilities for cancer chemoprevention, much attention is paid to curcumin—A broad-spectrum anticancer polyphenolic derivative extracted from the rhizome of Curcuma longa L. According to ClinicalTrials.gov at present there are no running pilot studies, which could assess possible therapeutic benefits from curcumin supplementation to patients with primary epithelial ovarian cancer. Therefore, the goal of this review was to evaluate potential preclinical properties of curcumin and its new analogues on the basis of in vivo and in vitro ovarian cancer studies. Curcumin and its different formulations have been shown to display multifunctional mechanisms of anticancer activity, not only in platinum-resistant primary epithelial ovarian cancer, but also in multidrug resistant cancer cells/xenografts models. Curcumin administered together with platinum-taxane chemotherapeutics have been reported to demonstrate synergistic effects, sensitize resistant cells to drugs, and decrease their biologically effective doses. An accumulating body of evidence suggests that curcumin, due to its long-term safety and an excellent profile of side effects should be considered as a beneficial support in ovarian cancer treatment strategies, especially in patients with platinum-resistant primary epithelial recurrent ovarian cancer or multidrug resistant disease. Although the prospect of curcumin and its formulations as anticancer agents in ovarian cancer treatment strategy appears to be challenging, and at the same time promising, there is a further need to evaluate its effectiveness in clinical studies. 相似文献
29.
An alternative RP‐HPLC method for the separation and determination of tocopherol and tocotrienol homologues as butter authenticity markers: A comparative study between two European countries
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