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71.
72.
The paper describes the logic of a computer method for identifying unbranched enzyme kinetic mechanisms on the basis of observed initial velocity and product inhibition patterns (Cleland, 1963). The method establishes initially an acceptable order of reactant addition and release, proceeds to list all the mechanisms consistent with that order and the data, and finally determines which of these can also explain data which require either non-competitive or dead-end inhibition. 相似文献
73.
Jeanette J. Chen Erla R. Smith Gary D. Gray Julian M. Davidson 《Primates; journal of primatology》1981,22(2):253-260
Seasonal changes in body weight, plasma testosterone and ejaculatory capacity were observed in five intact and two testosterone-implanted
castrated squirrel monkeys for a total of 13 months. Electroejaculation was employed for obtaining data concerning ejaculation.
In the intact animals, there were significant increases in body weight, ejaculate volume and plasma testosterone during the
breeding season. With the exception of one animal, there was also a decrease in ejaculation latency during the season. Seasonal
differences in the sperm count and sperm motility were not observed. Testosterone-implanted castrates showed changes in both
ejaculate volume and ejaculation latency similar to those seen in intact monkeys during the breeding season. The body weight
and plasma testosterone of the castrates remained quite constant throughout the year.
Supported by NIH grants HD 00778, MH 21178 and MH 23645. 相似文献
74.
Arlette Acoutte-Panvier Julian E. Davies Linda R. Gritz Barbara S. Littlewood 《Molecular & general genetics : MGG》1980,179(2):273-282
Summary The cytoplasmic ribosomal proteins (r-proteins) of seventeen yeast species of the genera Saccharomyces and Kluyveromyces were analyzed by one-dimensional gradient polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. The electrophoretic patterns of cytoplasmic r-proteins from different species display extensive differences in both the 40S and the 60S subunit. Relatedness of species suggested by r-protein patterns correlates well with that based on DNA/DNA homology (Bicknell and Douglas 1970). Immunochemical cross-reactions and antibiotic susceptibility tests were also used to compare different species.Analyses of r-proteins from two different interspecific hybrids showed that their ribosomes were hybrid, containing r-proteins from both parents. These findings are discussed in relation to the evolution of yeast species and the regulation of expression of r-proteins in cucaryotes. 相似文献
75.
Eugenia mcvaughii is described from a forest remnant of the Jardin Botánico of Caracas, Venezuela. Found also in the hills adjacent to Caracas, it may be considered as an endemic species of the Interior Coastal Cordillera. 相似文献
76.
Julian A. Steyermark 《Brittonia》1980,32(1):17-23
Three new species,Lubaria szczerbanii (Rutaceae),Croton guaiquinimae (Euphorbiaceae), andStomatochaeta colveei (Asteraceae), are described from the summit of Cerro Guaiquinima, Venezuela. The generic affinities betweenLubaria andMyllanthus, and betweenStomatochaeta andStenopadus are discussed. 相似文献
77.
Julian A. Steyermark 《Brittonia》1978,30(1):39-49
Ten new species (Billbergia manarae, Croizatia naiguatensis, Croton huberi, Rinorea oraria, Anaectocalyx manarae, Linociera avilensis, Cynanchum beatricis, C. manarae, Matelea costanensis, and M. manarae) are described in preparation for the forthcoming Flora of Avila and Naiguatá. 相似文献
78.
The enzyme tyrosinase (E.G. 1.14.18.1) has been immobilized in a polyacrylamide gel and intermittently assayed for enzyme activity over a period of 19 days using phenol as the substrate. The results of these studies indicate that the immobilized enzyme could be incorporated into a system to detect phenol and related compounds that are found in industrial effluents and as surface water contaminants. 相似文献
79.
80.
Maintaining up-to-date annotation on reference genomes is becoming more important, not less, as the ability to rapidly and
cheaply resequence genomes expands. 相似文献