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971.
Polygalacturonase (PG) activity and changes in respiratory intensity of apple fruits were investigated. The respiratory rate was decreased to a preclimacteric minimum from 30 Aug. to 20 Sept., Then increased to a climacteric peak (20–30 Sept.) and again drop down gradually with approaching the senescence stage. The PG activity was undetectable in a developing fruit until the onset climacteric phase. It rose rapidly after harvest, and reaching its highest level on 27 Oct. Just a month after the climacteric peak. The PG activity fell gradually. The amount of the fractions of pectic acid in fruits changed with the modifications of PG activity. With the ripening of fruits, the content of alcohol-soluble small molecules of pectic acids was increased from 12 to 13 5 mg/100 g of tissue, while the amount of alcohol- insoluble large molecules of pectic acids reduced from 530 to 280/100 g of tissue. PG activity would indicate the destruction of cell walls and the separation of cells. The onset of softening of fruits occurred 20 days after the rise of PG activity. It is supposed that the process of softening is directly controlled by PG activity. 相似文献
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A radioisotopic procedure for the assay of 3-hydroxybutyrate is presented. It is based on the measurement of NADH, generated in the 3-hydroxybutyrate dehydrogenase reaction, through the conversion of 2-[U-14C]ketoglutarate to 14C-labeled L-glutamate in the presence of beef liver glutamate dehydrogenase. The assay is linear in the range of 2.5 to 20.0 pmole/sample and about 100-times more sensitive than previous methods. The procedure proved useful for the measurement of 3-hydroxybutyrate in liver samples not exceeding 25 micrograms wet weight. 相似文献
975.
Rapid phosphorylation of Ets-2 accompanies mitogen-activated protein kinase activation and the induction of heparin-binding epidermal growth factor gene expression by oncogenic Raf-1. 总被引:8,自引:7,他引:8
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976.
Modelling and projecting the response of local assemblage composition to land use change across Colombia
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Susy Echeverría‐Londoño Tim Newbold Lawrence N. Hudson Sara Contu Samantha L. L. Hill Igor Lysenko Enrique Arbeláez‐Cortés Inge Armbrecht Teun Boekhout Jimmy Cabra‐García Yamileth Dominguez‐Haydar Guiomar Nates‐Parra Doris L. Gutiérrez‐Lamus Diego Higuera Paola Johanna Isaacs‐Cubides Carlos A. López‐Quintero Eliana Martinez Daniel Rafael Miranda‐Esquivel Luis Eduardo Navarro‐Iriarte Jorge Ari Noriega Samuel Eduardo Otavo Alejandro Parra‐H Katja Poveda Martha P. Ramirez‐Pinilla Juan Carlos Rey‐Velasco Loreta Rosselli Allan H. Smith‐Pardo José Nicolás Urbina‐Cardona Andy Purvis 《Diversity & distributions》2016,22(11):1099-1111
977.
Summary Phosphorus (H3P32O4) absorption was studied in detached bean leaves and leaf discs and later computed per unit surface area and per unit edge
length vis-a-vis discs of 4–18 mm diameters. Not only absorption through edge predominantly contributed to total disc absorption
it was also directly proportional to disc diameter.
Part of the work carried out during senior author's (BKG) tenure as IAEA expert at Bogota. 相似文献
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Ingrid Evans-Osses Andres Mojoli Marcia Holsbach Beltrame Denise Endo da Costa Wanderson Duarte DaRocha Thirumalaisamy P. Velavan Iara de Messias-Reason Marcel Ivan Ramirez 《FEBS letters》2014
To produce an infection Trypanosoma cruzi must evade lysis by the complement system. During early stages of infection, the lectin pathway plays an important role in host defense and can be activated by binding of mannan-binding lectin (MBL) to carbohydrates on the surface of pathogens. We hypothesized that MBL has a dual role during parasite-host cell interaction as lectin complement pathway activator and as binding molecule to invade the host cell. We used two polarized strains of T. cruzi, R4 (susceptible) and 860 (resistant) strains, to investigate the role of MBL in complement-mediated lysis. Interestingly R4, but not 860 metacyclic strain, markedly increases the invasion of host cells, suggesting that MBL drives the invasion process while the parasite deactivates the Lectin complement pathway. 相似文献