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741.
Tablés 1 to 3 were omitted from the final printing ofthis article. They are reprinted here. 相似文献
742.
M R Ondrias S D Carson S C Wood J A Shelnutt 《Comparative biochemistry and physiology. B, Comparative biochemistry》1984,79(4):637-642
Using resonance Raman difference spectroscopy, the Raman-active vibrational modes of hemoglobins from adult, neotenic, and larval forms of the salamander, Ambystoma tigrinum have been compared to each other and to human hemoglobin. The local heme environment of the adult and neotenic proteins were identical and differed from that of the larval protein. Differences were observed in modes sensitive to porphyrin pi electron density and axial ligation. Systematic differences were also observed between human and adult salamander hemoglobins particularly in modes sensitive to the heme vinyl environment. The relationship between these environmental differences, oxygen binding affinity, and the effects of allosteric modulators are discussed. 相似文献
743.
744.
A new staining method is described using naphthalene black 12B and Gurr's improved R66 Giemsa for staining all known crystal types produced by Bacillus thuringiensis. 相似文献
745.
746.
747.
Urease was immobilized on O-alkylated nylon tubes coated with polyaminated derivatives of starch or dextran. The specific activity of the enzyme coil and the relative stability of the immobilized enzyme, compared with immobilized urease derived from other nylon tube modifications, were enhanced. Also, the nonspecific binding of urease to O-alkylated nylon tubes was virtually eliminated by the coating process. 相似文献
748.
749.
Sporadic (less than regular weekly) coital activity is associated with a particular type of infertility—the short hyperthermic (luteal) phase. This preliminary report is the first suggestion that a reduced frequency of human sexual activity might, itself, be associated with subfertile reproductive function. 相似文献
750.