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71.
I. Chanarin M. Hutchinson Anne McLean Margaret Moule 《BMJ (Clinical research ed.)》1966,1(5484):396-399
72.
Substitution of Manganese for Tomato Juice in the Cultivation of Lactic Acid Bacteria 总被引:10,自引:7,他引:3
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Tomato juice was separated by chemical and physical methods into various active fractions, as measured by growth response and acid production by numerous lactic acid bacteria. Incineration of the treated extracts with little apparent loss in activity established the fact that the stimulatory component was of inorganic composition. Of the various cations tested, manganese was the only element that produced biological activity comparable to that of the original extract. Of the 71 strains of lactic acid bacteria tested, 63 strains showed a definite requirement for manganese or tomato juice. 相似文献
73.
Menzel, Margaret Y. (Florida State U., Tallahassee), and F. D. Wilson. Cytotaxonomy of twelve species of Hibiscus section Furcaria. Amer. Jour. Bot. 50(3): 262–271. Illus. 1963.—Metaphase-I chromosome numbers and pairing in 88 accessions showed that H. cannabinus, H. costatus, and H. surattensis are diploid (n = 18); and H. acetosella, H. aculeatus, H. bifurcatus, H.furcellatus, H. meeusei, H. radiatus, H. rostellatus and H. sabdariffa are tetraploid (n = 36), with similar low multivalent frequencies, hence probably allotetraploids each combining 2 well-differentiated genomes. No intraspecific variation in ploidy was found. Fertile, vigorous F1 hybrids between H.furcellatus and H. bifurcatus showed complete chromosome pairing (n = 36), confirming a close relationship between the parents. Two African strains of H. diversifolius were octoploid (n = 72) with low multivalent frequency and hence probably contain 4 differentiated genomes. At least 4, perhaps 5 or 6, differentiated genome groups are represented in tropical Africa, and at least 2 in the American tropics. 相似文献
74.
E. Y. Lasfargues Dan H. Moore Margaret R. Murray Cushman D. Haagensen E. C. Pollard 《The Journal of cell biology》1959,5(1):93-95
Thin sections of tissue cultures grown from tumors of the RIII high-breast-cancer strain mice were studied in the electron microscope. These tissues contain an abundance of particles whose morphology is consistent with biophysical measurement of the milk agent. These particles, found only extracellularly in our cultures, are formed at the cell membrane. The process of formation, as reconstructed from sections, appears to include a thickening and protrusion of the cell membrane which then evolves gradually into a dense sphere and separates from the cell in much the same manner as does influenza virus. The contents of the newly formed body are later rearranged to form a nucleoid within a membranous sac. 相似文献
75.
Margaret Kain Balbach 《American journal of botany》1965,52(4):317-330
A reinvestigation of the 4 American species of Lepidocarpon described from petrifactions and of Illiniocarpon cadyi, also described from petrifactions, shows that they are all conspecific. When they, in turn, are compared with specimens of the British petrifaction L. lomaxi, no significant differences can be demonstrated. The criteria cited as diagnostic for the American petrifaction species of Lepidocarpon were found to fail as bases of discrimination when 400 specimens of Lepidocarpon found in coal balls of Pennsylvanian age were studied. Measurements and observations made of a sample size of 136 of these 400 specimens reveal a degree of variation compatible with that of a single species. All previously described American and British petrifaction taxa fall within (or not significantly beyond) this range of variability of a single species as determined from this sample. Additional evidence concerning the 3-dimensional sporophyll structure of this one species of Lepidocarpon and the configurations obtained by certain planes of section through it have served to demonstrate that Illiniocarpon cadyi is in reality a taxon based on sectioned structures of the sporophyll of this Lepidocarpon species. Under the rules of priority, this species of Lepidocarpon and the following are assigned to Lepidocarpon lomaxi: Illiniocarpon cadyi, Lepidocarpon ioense, L. magnificum (megasporangiate form), L. crenatum and L. palmerensis. On the basis of the morphological evidence, the British petrifaction described as Lepidocarpon wildianum is also equated with L. lomaxi. 相似文献
76.
Relative Stability of Pertussis Vaccine Preserved with Merthiolate, Benzethonium Chloride, or the Parabens 总被引:2,自引:2,他引:0
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When stored at 4 C, or heated at 22 or 35 C followed by storage at 4 C, the potency of pertussis vaccines preserved with Merthiolate was more stable than the potency of vaccines preserved with benzethonium chloride or the parabens (methyl- and propyl-p-hydroxybenzoate). Without preservative, potency was more stable than in the presence of benzethonium chloride or the parabens, but less stable than when Merthiolate was present. The histamine-sensitizing factor of the vaccines likewise decreased with the loss of potency. The deleterious effect of benzethonium chloride and the absence of the stabilizing effect of Merthiolate were contributing factors, if not the sole cause, for the instability of pertussis vaccine in quadruple antigen vaccine (diphtheria and tetanus toxoids and pertussis and poliomyelitis vaccines). 相似文献
77.
Summary When grown with glucose, S. discophorus synthesized large amounts of poly--hydroxybutyrate which accumulated intracellularly as sudanophilic granules. The rate of endogenous oxygen consumption by such cells was markedly increased by Mn++ and even more by Mg++. It has been shown that these inorganic ions stimulate the oxidation of the intracellular poly--hydroxybutyrate.Dedicated by the senior author to Prof. C. B. van Niel on the occasion of his 70th birthday with gratitude for many unforgettable years of association, instruction and stimulation. 相似文献
78.
Margaret M. Clark 《BMJ (Clinical research ed.)》1967,2(5546):247-248
79.
Chromosome pairing was studied in the following hybrids: Hibiscus radiatus-meeusei (tetraploid F1), H. sabdariffa-meeusei (tetraploid F1 and spontaneous allooctoploid F2), and hexaploid H. acetosella-(sabdariffa-meeusei). Genome constitutions of the species adduced from these data are symbolized as follows: H. radiatus and H. acetosella, AABB; H. meeusei, AAXX; H.sabdariffa, XXYY or AAYY. 相似文献
80.
One hundred and forty-eight basal cell carcinomas were treated by curettage and electrosurgery. Twenty-six recurrent carcinomas were treated and 24 did not recur during a minimum two-year follow-up. Seventy-two newly diagnosed carcinomas were treated by the same method, and a two-year recurrence-free rate of 97.4% was obtained. About 50 new and recurrent lesions were treated in three patients in whom extensive cutaneous changes from actinic atrophy and previous therapy made the distinction between new and recurrent lesions difficult or impossible. This technique has a particular place in the management of multiple lesions. Patient acceptance is good. Lesions at some sites, e.g. on the nose, where closure of a wound is difficult, are better managed by this method than by surgical excision. Secondary infection is rare and the cosmetic results are excellent. 相似文献