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181.
Seed Proteins of Peas in Relation to Nitrogen Fixation 总被引:2,自引:0,他引:2
The influence of the source of nitrogen on the amount and compositionof the seed protein has been examined. The plants were grownin sterile compost and those that had received their nitrogenas ammonium nitrate compared with those in which nitrogen fixationoccurred in the root nodules. The absence of nodules in theformer and the presence of nitrogen fixation in the latter wasconfirmed. The source of nitrogen did not affect the amountsof extractable seed protein, the proportions of the differentfractions or their composition. 相似文献
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JOHNSTON CD 《Archives of biochemistry and biophysics》1951,31(3):375-382
DDT and several of its related compounds were found to be inhibitory to rat heart succinoxidase at concentrations of from 10?4 to 10?5M, the degree of inhibition being about 70–90% at the higher concentrations. This inhibition could also be shown for cytochrome oxidase, but not for succinic dehydrogenase. The inhibition was demonstrable when the insecticide or its derivatives were added to the enzyme system as alcoholic solutions. Cholesterol at the same concentrations did not inhibit succinoxidase.When DDT was present in an oil emulsion, only a slight inhibition could be shown toward the succinoxidase system, even though the concentration in the emulsion was 10 times that of the highest level in alcohol.DDA, the acetic acid derivative of DDT, and a known metabolite thereof, was much less inhibitory toward the succinoxidase and cytochrome oxidase systems, even at 5 × 10?4M. 相似文献
184.
Polychaete systematics: Past and present 总被引:13,自引:0,他引:13
In this paper, we first demonstrate the historical background for the current unsatisfactory state of systematics of the polychaetes. We then briefly discuss our knowledge of internal and external structures. A review of the polychaete families makes up the third section; 81 families are treated in detail. Five families have been recently synonymized with others, and six families are too poorly known to be sufficiently characterized. Fossil polychaetes are briefly mentioned, with specific attention to problems associated with incorporating them in recent systematics.
The traditional separation in 'errant' and 'sedentary' polychaetes has increasingly become recognized as being unsatisfactory; however, the current trend towards grouping the polychaetes in many orders without specifying the relationships among the orders, is no more satisfactory. The lack of consistent morphological information is a major source of uncertainty. Intensive morphological studies should remove terminological ambiguities and alleviate some of the problems. 相似文献
The traditional separation in 'errant' and 'sedentary' polychaetes has increasingly become recognized as being unsatisfactory; however, the current trend towards grouping the polychaetes in many orders without specifying the relationships among the orders, is no more satisfactory. The lack of consistent morphological information is a major source of uncertainty. Intensive morphological studies should remove terminological ambiguities and alleviate some of the problems. 相似文献
185.
SYNOPSIS. Haemogregarina bigemina was found in all Blennius pholis which exceeded 5.0 cm in length, but in none measuring less than 3.5 cm. No exoerythrocytic development was recorded. The first B. pholis eggs hatched in May while the first patent infections of H. bigemina occurred from September onward in metamorphosed fish. Consequently, if the life cycle of H. bigemina includes a vector, that organism is active between May and September at least. Circumstantial evidence indicates that the hematophagous isopod, Gnathia maxillaris and not leeches, could be a vector of H. bigemina. Developmental stages of sporozoa were found in a small number of the isopods which had fed on infected B. pholis but the parasites could not be identified as H. bigemina with certainty. Subcellular organization, typical of sporozoa, was recorded by electron microscopy of H. bigemina. 相似文献
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FREDRIK PLEIJEL GREG W. ROUSE CHRISTINE RUTA HELENA WIKLUND ARNE NYGREN 《Zoological Journal of the Linnean Society》2008,152(4):625-634
Vrijenhoekia balaenophila gen. nov., sp. nov. (Polychaeta, Hesionidae) is described from a whale carcass at near 3000 m depth in Monterey Canyon off the coast of California. The phylogenetic relationships of V. balaenophila are assessed in a parsimony analysis of morphological data together with nucleotide data from 28S rDNA, 16S rDNA and cytochrome oxidase I genes. Within the hesionids V. balaenophila belongs to Psamathini, where it is the sister group to Sirsoe . Among psamathins it is morphologically distinguished by having six glandular lip pads around the mouth opening, papilla-shaped neuropodial lobes on segment 3, extreme length of the dorsal cirri, and by a characteristic growth pattern in which the maximum number of segments is already formed in subadults, and further growth takes place through size increase of the segments. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 625–634. 相似文献
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