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41.
Summary Host cell reactivation capacity for ozone T3 phage was determined for differentE. coli strains deficient in one or more of the DNA repair mechanisms. The results indicate that DNA polymerase I appears to play a key role in the repair of damage produced on the DNA by ozone while thelexA gene product seems to play a minor one.This research was sponsored by the National Sciences and Engineering Council of Canada. One of us (PLH) acknowledges a scholarship from the NSERCof Canada. 相似文献
42.
Summary The nature of antigen Dd, an antigen present in the extracts of human dandruff which precipitates human sera selectively, and antibodies reacting with it are reported.This work was supported through U.G.C. Grant No. F.23-230/75/SR II. H.K. participated in this study, first as J.R.F. of U.G.C. and then as S.R.F. of I.C.M.R. We are grateful to Dr Baruch S. Blumberg for his invaluable suggestions and to Professor H. Walter for the gift of IgG, IgM and IgA immune sera. 相似文献
43.
Chromosomal effects of adeno-associated virus vector integration. 总被引:17,自引:0,他引:17
Adeno-associated virus (AAV) vectors are currently being used in several clinical gene-therapy trials (see the NIH OBA Human Gene Transfer Clinical Trials Database); however, little is known about the chromosomal effects of vector integration. Here we report that integrated vector proviruses are associated with chromosomal deletions and other rearrangements and are frequently located on chromosome 19 (although not at the wildtype AAV integration site). 相似文献
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45.
Jacob W. Ulvila 《Journal of forecasting》1985,4(4):377-385
Recent years have seen an increasing cross-fertilization between the fields of decision analysis and forecasting. Decision-analytic models often require forecasts as inputs, and aspects of the Bayesian decision-theoretic framework underlying decision analysis have proved useful to forecasting, particularly in contexts where subjective judgemental inputs are required. This paper describes the use of decision tree analysis for forecasting and illustrates its use for corporate divisional forecasting and planning. A specialized decision-analytic technique, acts as events, is also described and illustrated to forecast a new product's earnings. Conclusions are drawn about the applicability of decision analysis for forecasting. 相似文献
46.
J. W. Faigle H. Stierlin H. Mory T. Winkler H. -P. Kriemler 《Cellular and molecular life sciences : CMLS》1985,41(4):476-478
Summary Indoxyl derivatives were detected as minor products among the urinary metabolites of two trial drugs, a benzodiazepine (GP 55 129) and a benzophenone (CGP 11 952). Their structures were elucidated by NMR and mass spectroscopy. Presumably, metabolites containing potential aldehyde functions react spontaneously with endogenous indoxyl. Such derivatives have not hitherto been encountered in drug metabolism. 相似文献
47.
A diffusion chamber technique based on time-lag analysis for the estimation of effective diffusion coefficients of radiolabelled macromolecules of varying molecular weights through native mucus gel is reported. For all solutes studied, a reduction in effective diffusion coefficients was observed with a retardation of solute flux in both aqueous and mucus layers. Over the molecular weight range of solutes investigated (126-186,000 Daltons), a consistent effect of molecular weight was evident with regard to the retarding effect of mucus. No apparent or absolute molecular weight cut-off for macromolecular transfer was exhibited. However, at high molecular weights (greater than 30,000 Daltons) the retardation was greatly enhanced. The results confirm that mucus can be regarded as a gel with finite pores, but that it does not constitute an absolute barrier to even high molecular weight solutes. 相似文献
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50.
卢武星 《北京师范大学学报(自然科学版)》1994,(4)
1.0MeV208Pb离子在非晶Si中的投影射程RP和射程偏差ΔRP作为注量和温度二者的函数用背散射法进行测定.注量的变化范围为5×1013~7×1014cm-2.注入是在室温和t=-120℃下完成的.由由实验所确定的投影射程,射程偏差与注量或温度无关,并且分别等于295和72.2nm.与TRIM86的计算结果相比较,发现RP的偏离为18%,而ΔRP的偏离为36%.RP和ΔRP二者与注量及温度的无关性,排除了所观察到的与TRIM的矛盾是由于注入期间辐射增强扩散或离子束混合效应而引起的解释。 相似文献