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81.
Subhash C. Gupta Catherine Potrikus Reese J. Woodland Hastings 《Archives of microbiology》1986,143(4):325-329
A recombinant plasmid which carried a 5 kb fragment of Vibrio harveyi DNA containing the luxA and luxB genes was mobilized from Escherichia coli into luminescence-deficient mutants of V. harveyi. The cloned genes complemented a temperature sensitive luciferase mutation, but failed to complement lesions in two different aldehyde deficient mutants. Expression of the cloned genes was not subject to autoinduction in either E. coli or in V. harveyi. 相似文献
82.
The use of a recently developed cation-exchange HPLC packing material for the separation of hemoglobin types in human blood has been investigated. Adult and newborn hemolysates from normal individuals and from subjects with hemoglobin disorders were analyzed using a weak cation carboxymethyl-bonded phase on 5-micron-particle-size silica. Elution was accomplished using a Bistris (2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)-1, 3-propanediol) gradient. Seven well-resolved HbA1 fractions eluted before the major HbA peak. Hbs A1a, A1b, A1c and an HbA1 fraction that increased with aging of the hemolysates were separately eluted. HbF when present or when added to the hemolysates eluted as a distinct peak. HbA was followed by Hbs A2, S, and C when present. An early-eluting peak corresponding to Hb Bart's was identified in newborn hemolysates. It is concluded that cation-exchange HPLC provides a new tool for the reliable separation of minor hemoglobin components. 相似文献
83.
Genomic and copy-back 3'' termini in Sendai virus defective interfering RNA species 总被引:7,自引:3,他引:4 下载免费PDF全文
Direct sequencing of nine Sendai virus defective interfering RNA species revealed two kinds of 3'-terminal sequences. Six RNA species had 3' termini identical to the virus genome (negative strand), confirming that internal deletions are a frequent cause of Sendai virus defectiveness. The other three RNA species had 3'-terminal sequences identical to that described as the complement of the 5' terminus of the virus genome (R. A. Lazzarini, J. D. Keene, and M. Schubert, Cell 26:145-154, 1981), indicating that they are of the copy-back type. Extensive homology between these two types of 3' sequences evidently accounts for the ability of the copy-back sequence to function as an initiation signal for viral RNA replication. There may not be a selective advantage of one type of terminus over the other, since one defective interfering strain possessed two RNA species, one of which had the genomic 3' terminus and the other copy-back type. 相似文献
84.
Akhil G. Jhingran R.C. Gupta Suprabhat Ray A.K. Agarwal M.M. Singh Nitya Anand 《Steroids》1983,42(6):627-634
The syntheses of (±) 2α,6β-diethyl-7α-ethynyl-3α-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol (), (±)2β,6β-diethyl-7α-ethynyl-3β-(-methoxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and (±) 2α,6β-diethyl-7α-ethynyl-3β-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and their derivatives, which are essentially B-seco-steroids having and geometries have been carried out. A study of their antiimplantation activities (AI) and receptor binding affinities (RBA) show that compounds are biologically most potent, followed by the corresponding and compounds. The most potent compound is active at 1 mg/kg in rats. Introduction of 7α-ethynyl group increases their AI activity; however, no significant effect on their RBA is observed. 相似文献
85.
From the uppermost parts of the Muth Quartzite Formation the following ammonoids are described which here are reponed from the Himalayas for the first time:Discoclymenia cucullata (v. Buch);Prionoceras (Imitoceras) intermedium Schindewolf;Pr. (I.) cf.rotundum Petter;Cyrtodymenia sp.; andDiscoclymenia striata (Münster). The levels containing ammonoids appear in the Famennian V(Clymenia zone). Their extension up to the earliest Tournaisian(Gattendorfia zone) is not likely although theoretically it cannot be excluded. 相似文献
86.
Two new compounds, isolated from the rhizomes of Cryptocoryne spiralis, have been characterized as ethyl 14-oxotetracosanoate and 15-oxoeicosanyl 14-oxoheptadecanoate by spectral data and chemical studies. Hentriacontane and sitosterol have also been isolated and identified. 相似文献
87.
88.
(Ca2+ or Mg2+)-ATPase in lung lamellar bodies 总被引:1,自引:0,他引:1
89.
Determination of Rubella Hemagglutination-Inhibiting Antibody in Whole Blood 总被引:1,自引:0,他引:1 下载免费PDF全文
A technique is described for determination of rubella hemagglutination-inhibiting antibody in only 50 to 100 muliters of whole blood. 相似文献
90.