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921.
922.
923.
SAPROPHYTIC BEHAVIOUR OF SOME CEREAL ROOT-ROT FUNGI: IV. SAPROPHYTIC SURVIVAL IN SOILS OF HIGH AND LOW FERTILITY 总被引:3,自引:0,他引:3
F. C. BUTLER 《The Annals of applied biology》1959,47(1):28-36
In southern New South Wales the resumption of ley land for wheat growing has been accompanied by an increase in take-all ( Ophiobolus graminis ) and Fusarium root rot ( Fusarium culmorum ). No such increase has been observed in foot and root rots of wheat caused by Helminthosporium sativum and Curvularia ramosa.
It is shown experimentally that these differences are related to the relative capacity of the causal fungi to persist in wheat straw buried in each of two unsterilized soils which, because of past cultural treatments, differed in their organic carbon and total nitrogen content. While the saprophytic survival of O. graminis and F. culmorum was promoted by high soil fertility that of H. sativum was markedly depressed. The survival of C. ramosa was little affected by soil fertility.
F. culmorum, H. sativum and C. ramosa each remained viable under the soil conditions best suited to their survival in one-third to one-half of the test straws for 2 years but O. graminis was not recovered after the 52nd week of sampling. 相似文献
It is shown experimentally that these differences are related to the relative capacity of the causal fungi to persist in wheat straw buried in each of two unsterilized soils which, because of past cultural treatments, differed in their organic carbon and total nitrogen content. While the saprophytic survival of O. graminis and F. culmorum was promoted by high soil fertility that of H. sativum was markedly depressed. The survival of C. ramosa was little affected by soil fertility.
F. culmorum, H. sativum and C. ramosa each remained viable under the soil conditions best suited to their survival in one-third to one-half of the test straws for 2 years but O. graminis was not recovered after the 52nd week of sampling. 相似文献
924.
925.
926.
927.
Andrew W. Saxe Ji-Won Yoon Phillip Gorden Murray F. Brennan 《In vitro cellular & developmental biology. Plant》1982,18(10):884-890
Summary Dispersed cells from both fresh and cryopreserved human insulinoma have been maintained in cell culture. Initial yield of
viable cells was 50% for fresh and 25% for cryopreserved tissue. Viability of cells in culture was documented by increasing
numbers of cells (doubling time approximately 5 d initially and 2 d at the sixth subculture for both fresh and cryopreserved
tissue) and continued release of insulin over time (approximately 100 ng/ml per 105 cells at 10 d and 175 ng/ml per 105 cells at 30 d of culture for both fresh and cryopreserved tissue). Evidence that cells growing in culture were beta cells
was provided by: (a) recovery of intracellular and extracellular immunoreactive insulin (IRI), (b) electron microscopic morphology,
and (c) immunohistochemical staining. Cells from fresh insulinoma incubated with increasing concentrations of extracellular
glucose released increasing amounts of IRI up to approximately 15 mM glucose, which paralleled changes in plasma insulin obtained during a preoperative glucose tolerance test.
Under an Intergovernmental Personnel Act Exchange from the Department of Surgery, University of California, Davis, Sacramento
Medical Center. 相似文献
928.
929.
Leonard F. Liebes Howard Fleit Dorothea Zucker-Franklin Robert Silber 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,633(2):245-257
Tubulin has been purified from human blood and tonsil lymphocytes. Using gel filtration, the molecular weight of human lymphocyte tubulin was estimated to be 119 000. The proteins was shown to consist of two subunits, with molecular weights of 61 000 and 58 000 comparable to the α and β polypeptides of human brain tubulin. A partial identity reaction was observed between lymphocyte tubulin and human tubulin when tested by double immunodiffusion against a rabbit anti-human brain tubulin antibody. In the presence of GTP, the purified protein polymerized to form microtubules. Tubulin was localized to the cell's juxtacentriolar region by immunofluorescence and electron microscopy. When assayed by a colchicine-binding assay corrected for time decay, the binding affinity was 1.50 ± 0.86 · 106M?1 and a level in normal lymphocytes of 1.21 · 10?2 ± 0.79 g/g of soluble protein was determined. Since chronic lymphocytic leukemia lymphocytes have an anomalous capping behavior as well as an unusual susceptibility to colchicine toxicity, the properties and levels of tubulin were determined in these cells. Similar values were obtained for the level, decay rate, molecular weight, and Ka for colchicine as for normal lymphocytes. Chronic lymphocytic leukemia lymphocyte tubulin polymerized in a normal fashion. It thus appears that a decrease in the quantity or function of tubulin does not account for these anomalies in the chronic lymphocytic leukemia lymphocyte. 相似文献
930.
Summary Eastern screech owls bring live blind snakes to their nestlings, whereas all other prey are delivered dead. Some of the snakes are eaten but most live in nest debris, where they eat soft-bodied insect larvae from the decomposer community in fecal matter, pellets, and uneaten prey. Consumption of larvae may reduce larval parasitism on owl nestlings or larval competition with nestlings for food stored in the nest, because nestlings with live-in blind snakes grow faster and experience lower mortality than same-season broods lacking snakes. We propose a commensalistic association in which the screech owl benefits reproductively and the live-in blind snake is not affected. 相似文献