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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
Edwards KW Ogg M Bellerive A Britton DI Hyatt ER MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kotov S Kravchenko I Kwak N Lam H Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR Wappler F Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Sung M White C Wolf A Zoeller MM Butler F Fu X Nemati B 《Physical review letters》1995,74(17):3331-3335
932.
van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871
933.
934.
Youngwon Lee Charles P. Emerson Myoung Hee Kim 《Applied biochemistry and biotechnology》1995,55(3):231-240
TnINEO fusion gene was constructed by fusing 3.4-kbp of quailTnI genomic DNA sequences spanning the promoter to exon 5 and aneo gene in frame. A myoblast cell line was established after transfection of pTnINEO. Since this cell line was passaged several
times, a high frequency of neomycin (G418) sensitivity conversion was detected. Two drug-resistant variants were analyzed
through genomic Southern blot and S1 nuclease protection assay. One variant has a mutation(s) in the regulatory element that
activated the dormantTnI promoter-enhancer in myoblast, and the other has shown the genomic rearrangement. This result presented the possibility of
isolating factor(s) that activate the muscle-specificTnI promoter simply by screening drug-resistant cells having appropriate mutations. 相似文献
935.
Summary A new method for the determination of microcystins PR and LR in cyanobacterium was developed using cyano-type prepacked cartridges. The microcystins were extracted with 10% acetic acid and the extract applied to a Baker 10 cyano cartridge. After elution from the cartridge with 0.5M acetic acid-acetonitrile (19) the microcystins were determined by HPLC. Better recoveries and chromatograms were observed than with ODS cartridges. 相似文献
936.
Using the temperature dependence of pKa for acetic acid, the pKa for 2,5-dinitrophenol have been spectrophotometrically determined in acetate buffer at elevated temperatures under the saturation vapor pressures. For 2,5-dinitrophenol $$pK_a = - 33.206 + 2106.7/T + 5.495\ln T$$ where T is in Kelvin. Similarly, pKa values of propionic acid were obtained at temperatures from 25°C to 175°C producing $$pK_a = - 43.703 + 2128.6/T + 7.2686\ln T$$ From this result, several thermodynamic functions of propionic acid were calculated and compared with those obtained from emf measurement. 相似文献
937.
Five crown ethers, namely, 4'-picrylamino-5'-nitrobenzo-18-crown-6 (I), dibenzo-18-crown-6 (III), dibenzo-30-crown-10 (IV), dicyclohexano-18-crown-6 (V) and bis-[(benzo-15-crown-5)-15-ylmethyl pimelate] (VI) have been compared with valinomycin (II) for their role as potassium ion-sensors in PVC matrix membrane ion-selective electrodes (ISEs). Sensor I was found to be the best, but fell short of the high quality of the well established sensor II (valinomycin) in terms of selectivity towards potassium over sodium and ammonium. Nevertheless, electrodes made from membranes containing sensor I, 2-nitrophenyl octyl ether (NPOE) or 2-nitrophenyl phenyl ether and potassium tetra-p-chloro-phenylborate (anion excluder) in PVC were of long lifetimes. The loss of slope of the ISEs is linked to small falls in the electrical resistance of the ISE membranes; this being associated with leaching of sensor and solvent mediator from the membranes into test or storage solutions. No chromatographic evidence was found of anion excluder being leached. 相似文献
938.
J. -E. Lee 《Theoretical and Mathematical Physics》1994,101(2):1281-1288
This paper is a continuation of work by Forest and Lee [1,2]. In [1,2] it was proved that the function theory of periodic soliton solutions occurs on the Riemann surfaces ? of genusN, where the integrals over paths on ? play the most fundamental role. In this paper a numerical method is developed to evaluate these integrals. Predisely, the aim is to develop a computational code for integrals of the form $$\int\limits_\gamma {f(z)\frac{{dz}}{{R(z)}}, or} \int\limits_\gamma {f(z)R(z)dz,} $$ wheref(z) is any single-valued analytic function on the complex planeC, andR(z) is a two-valued function onC of the form $$R^2 (z) = \prod\limits_{k = 1}^{2N + \delta } {(z - z_0 (k)), \delta = 0 or 1,} $$ where {z 0(k),1≤k≤2N+δ} are distinct complex numbers which play the role of the branch points of the Riemann surface ? = {(z, R(z))} of genusN?1+δ. The integral path γ is continuous on ?. The numerical code is developed in “Mathematica” [3]. 相似文献
939.
940.
Cinabro D Henderson S Liu T Saulnier M Wilson R Yamamoto H Bergfeld T Eisenstein BI Gollin G Ong B Palmer M Selen M Thaler JJ Sadoff AJ Ammar R Ball S Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kwak N Lam H Kubota Y Lattery M Nelson JK Patton S Perticone D Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Nemati B O'Neill JJ Severini H Sun CR Zoeller MM Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Malchow R Morrow F Skovpen Y 《Physical review letters》1994,72(10):1406-1410