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871.
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874.
John Seale 《BMJ (Clinical research ed.)》1964,2(5423):1522-1524
875.
876.
Neville Prentice W. C. Burger Jeannine Kastenschmidt John David Huddle 《Physiologia plantarum》1967,20(2):361-367
The activity of barley and wheat peptidases which hydrolyze alpha-N-benzoyl-dl-arginine-p-nitronnilide (BAPA) and alpha-N-benzoyl-l-arginine ethyl ester (BAEE) has been measured in proximal and distal portions of ungerminated grain and in these tissues during 6 and 7 day incubations. The proximal portion of ungerminated barleys contained the major part of both the acidic (BAPA-ase and acidic BAEE-ase) and neutral (neutral BAEE-ase) peptidases. In ungcrminated wheat these acidic and neutral peptidases were nearly evenly distributed between the proximal and dislal portions. Commercial wheat embryo was very high in acidic peptidase but contained no neutral peptidase. During the germination of both wheat and barleys, acidic and neutral peptidase activity in the seedlings increased with time. No such consistent increase was observed for aleurone and starchy endosperm tissue for any of these grains. Aleurone and starchy endosperm tissue incubated in the absence of the proximal portion of the kernel showed reduced peptidase activities. 相似文献
877.
Summary Recombinant B factors were recovered from crosses of class Ixclass III B factors. Factors of class III are constituted of two loci, but intrafactor recombination occurs at a low frequency. B of class III B factors differs in its properties from B of class I, but B is identical with B of class I. The B locus has at least two alleles. 相似文献
878.
The action spectrum for promotion of elongation of protonemata of Onoclea sensibilis has peaks at 400–420, 580–600 and 640–660 nm. The largest growth increments at saturating light doses are produced by yellow and far-red light. Elongation induced by yellow and far-red irradiation persists in old as well as young filaments, while red-light promotion is found only in young filaments. The growth promotion caused by yellow light is partially reversed by red light down to the level of growth produced by red irradiation alone. Elongation of rhizoids is under reversible red, far-red control, while yellow light is inactive. A model is proposed and discussed in which the light-sensitive elongation of filaments is accounted for by the presence of three distinct photoreceptors: phytochrome; a pigment absorbing yellow light. P580; and a pigment absorbing blue light, P420. 相似文献
879.
Properties of r Mutants of Bacteriophage T4 Photodynamically Induced in the Presence of Thiopyronin and Psoralen 总被引:15,自引:2,他引:13 下载免费PDF全文
About 4 x 10(-4)r mutants were induced per lethal hit, a frequency characteristic of weak mutagens. Collections of mutants produced in the presence of either dye were indistinguishable in most of their properties. The rII mutants differed sharply from spontaneous mutants in their mutational spectra (fine scale map distribution) and their reversion responses to specific mutagens. Few or none of the induced mutants were induced to revert with proflavine (sign mutants; reading frame shift mutants). A majority were induced to revert with base analogues (base pair substitution mutants), and about half of these also responded to the hydroxymethylcytosine-specific agent hydroxylamine. A large minority of the mutants reverted spontaneously but failed to respond either to proflavine or to base analogues. We believe these mutants, as well as some of the mutants which did respond to base analogues, to be transversions (base pair substitutions which reverse the purine-pyrimidine orientation). 相似文献
880.
Jerome Harold Kay Harold K. Tsuji John V. Redington Yasunaru Kawashima Yuzuru Kagawa Takashi Yamada Peter Caponegro Adolfo Mendez 《The Western journal of medicine》1967,106(3):165-169
A disc valve of new design was used successfully for the replacement of the mitral valve in patients with rheumatic mitral valve disease. This valve would appear to have the following advantages over the mitral ball valve prosthesis:• Lower left atrial pressure after replacement.• Elimination of the hazard of left ventricular outflow tract obstruction with mitral valve replacement.• Decreased incidence of thromboembolization.• Abolition of possibility of ventricular septal irritation.Despite the better outlook for this valve compared with the ball valve for mitral valve substitution, the mitral valve should always be repaired whenever feasible. Repair is possible in the majority of patients. 相似文献