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101.
R Rastogi S Sharma N Anand A Dutta N Fatma R K Chatterjee A B Sen 《Journal of helminthology》1984,58(3):251-254
The synthesis and filaricidal activity of 1-iso-butoxycarbonyl-4-methylpiperazine against Litomosoides carinii in Sigmodon hispidus and Dipetalonema viteae in Mastomys natalensis is reported. At an intraperitoneal or oral dose of 3 mg/kg given for 6 days, the compound removed 91% of the circulating microfilariae but had no effect on adult L. carinii. However, it killed all microfilariae and adults of D. viteae at a subcutaneous dose of 50 mg/kg given for 6 days. The compound also possessed chemoprophylactic activity against the larvae of L. carinii and D. viteae at a dose of 30 and 50 mg/kg respectively. 相似文献
102.
Summary A major portion of the genomes of three millet species, namely, barn yard millet, fox tail millet and little millet has been shown to consist of interspersed repeat and single copy DNA sequences. The interspersed repetitive DNA sequences are both short (0.15–1.0 kilo base pairs, 62–64% and long (>1.5 kilo base pairs, 36–38%) in barn yard millet and little millet while in fox tail millet, only long interspersed repeats (>1.5 kilo base pairs) are present. The length of the interspersed single copy DNA sequences varies in the range of 1.6–2.6 kilo base pairs in all the three species. The repetitive duplexes isolated after renaturation of 1.5 kilo base pairs and 20 kilo base pairs long DNA fragments exhibit a high thermal stability with Tms either equal to or greater than the corresponding native DNAs. The S1 nuclease resistant repetitive DNA duplexes also are thermally stable and reveal the presence of only 1–2% sequence divergence.The present data on the modes of sequence arrangement in millets substantiates the proposed trend in plants, namely, plants with 1C nuclear DNA content of less than 5 picograms have diverse patterns of sequence organization while those with 1C nuclear DNA content greater than 5 picograms have predominantly a short period interspersion pattern.Abbreviations kbp
kilobase pairs
NCL Communication No. 3606. 相似文献
103.
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
104.
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
105.
Genomic and copy-back 3'' termini in Sendai virus defective interfering RNA species 总被引:7,自引:3,他引:4
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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
106.
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
107.
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
108.
Putrescine, spermidine and spermine of high vigour, low vigour and non-viable (classes 1, 2 and 3 respectively) seeds of Oryza sativa increased with loss of viability. The largest concentration of spermine was found in non-viable embryos. Spermine was absent in the husks of all the three categories of seeds. Arginine decarboxylase was greatest in high vigoured seeds and its activity gradually declined with loss of viability. However, diamine oxidase and polyamine oxidase activities gradually increased with the loss of viability of the seeds while DNA, RNA and protein contents decreased. The total content of polyamines increased on kinetin treatment but declined on ABA treatment. DNA, RNA and protein followed the same trend as polyamines. The polyamine contents increased by ca 3- and 4-fold, respectively, in high vigoured and low vigoured seeds on 10?4 M kinetin treatment. The activity of ADC followed the same change as that of the polyamines in both cases, but the reverse was observed for the activities of diamine and polyamine oxidases. 相似文献
109.
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