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71.
Insulin rapidly induces rat liver S14 gene transcription 总被引:1,自引:0,他引:1
72.
E Hu K Watkins S Groshen S C Chen B Malloy R Agah P Nichols J Parker A Martin M G Boosalis 《Molecular biotherapy》1990,2(2):96-103
A phase I trial of interleukin-2 and interferon gamma combination treatment in patients with advanced malignancies was performed based on preclinical in vitro and in vivo data which demonstrated synergistic antitumor effect. The toxicities, immune parameters, and tumor responses are described. The clinical and biologic maximal tolerated doses were extrapolated from these data. 相似文献
73.
74.
Y Saga J S Tung F W Shen T C Pancoast E A Boyse 《Molecular and cellular biology》1988,8(11):4889-4895
75.
76.
77.
Recombinational resolution in primate cells of two homologous human DNA segments with a gradient of sequence divergence. 总被引:1,自引:0,他引:1
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![点击此处可从《Nucleic acids research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Human alpha-thalassemia-2 genotype -alpha 4.2 is the result of meiotic recombination between two 1.3 kb long, homologous DNA segments, X(alpha 2) and X(alpha 1), located in the adult alpha globin locus. The two segments can also undergo intramolecular recombination on extrachromosomal vectors transfected into mitotically dividing primate cells (COS 7). The existence of a gradient of sequence divergence between X(alpha 2) and X(alpha 1) makes them an interesting system to study the relationship between efficiencies of homologous DNA recombination and the extent of dispersed and localized base mismatches. By partial restriction mapping and DNA sequencing of plasmids recombined in COS 7 cells and rescued from bacteria HB 101, we have determined the distribution of recombinational resolution sites along the two X blocks. Most, if not all, of the homologous recombination events between the two X blocks appear to be single crossing-over without efficient gene correction or repair of base mismatches. The distribution of the sites of recombinational resolution is inversely correlated with that of the gradient of sequence divergence, with only approximately 7% of the X recombinants resolved within the 3' third of the X blocks where two diverged Alu family repeats reside. The Alu sequence within which one of the X recombinants resolved is homologous to a previously characterized alpha thalassemia deletion point. 相似文献
78.
M Hu P J Sinko A L deMeere D A Johnson G L Amidon 《Journal of theoretical biology》1988,131(1):107-114
The boundary layer approach to analyzing the results of the perfused intestinal segment method of measuring membrane permeabilities is applied to the amino acids; leucine, valine, phenylalanine, lysine and aspartic acid and the beta-lactam antibiotics, cephalexin and penicillin V. The analysis indicates that in determining the membrane parameters, Pw vs. Cw data are preferable to using Jss = PwCw vs. Cw data. It is further shown that the carrier permeability, Pc* = Jmax*/Km, may be the most significant parameter to consider since luminal amino acid or drug concentration may generally be below the Km value. A comparison of P*c values for the beta-lactams with results for passively absorbed compounds indicates that the cephalosporins would be expected to be well absorbed orally based on the perfusion results. This suggests that this approach may be useful in estimating oral drug absorption for compounds that are absorbed passively as well as by a carrier-mediated mechanism. 相似文献
79.
Functional organization of the murine leukemia virus reverse transcriptase: characterization of a bacterially expressed AKR DNA polymerase deficient in RNase H activity 总被引:6,自引:3,他引:3
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![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
J G Levin R J Crouch K Post S C Hu D McKelvin M Zweig D L Court B I Gerwin 《Journal of virology》1988,62(11):4376-4380
80.
A developmentally regulated hydroxyproline-rich glycoprotein in maize pericarp cell walls 总被引:12,自引:3,他引:9
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![点击此处可从《Plant physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We have studied the accumulation of peptidyl hydroxyproline in the pericarp of developing maize (Zea mays L., Golden cross Bantam sweet corn) kernels. Although this hydroxyproline accumulates throughout development, it is most soluble and its content per milligram dry weight greatest at midmaturation stages of development. Salt-soluble proteins containing this hydroxyproline from isolated cell walls of developing kernels were fractionated on a CsCl density gradient and on a Chromatofocusing column, resulting in the purification of an hydroxyproline-rich glycoprotein, PC-1. PC-1 is a basic protein of approximately 65 to 70 kilodaltons in molecular weight with an isoelectric point of at least 10.2 and a density of 1.38 to 1.39 in CsCl. Amino acid composition data indicate that it is rich in hydroxyproline, threonine, proline, lysine, and glycine. Its relation to dicot extensin is discussed. 相似文献