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1.
2.
S. H. Habib S.-E. Ooi Ond?ej Novák Danu?e Tarkowská Jakub Rol?ík Karel Dole?al S. S. R. Syed-Alwee C.-L. Ho P. Namasivayam 《Plant Growth Regulation》2012,68(2):313-317
Comparative mineral and hormonal analyses were made on tissue culture derived truncated leaf syndrome and wild type oil palm seedlings. Mineral analysis confirmed that Boron, Zinc and chlorophyll levels were significantly lower in truncated leaf syndrome leaves than those of wild type. Hormonal analysis also revealed various cytokinin derivatives such as trans-zeatin, trans-zeatin riboside, trans-zeatin O-glucoside and trans-zeatin riboside 5??mono phosphate were significantly higher in truncated leaf syndrome leaves compared to wild type leaves. Brassinolide level was also significantly higher in truncated leaf syndrome leaves than those of the wild type. These observations suggest that the truncated leaf syndrome abnormality could be associated to high cytokinin and brassinosteroid production which affects the uptake of Boron and Zinc. 相似文献
3.
Five popular but iron-inefficient cultivars were crossed with three efficient genotypes and both parents and F1s were evaluated for iron-efficiency in potted calcareous and noncalcareous soil. The iron-efficient genotypes were dark green or green in both noncalcareous and calcareous soils whereas inefficient types were light green to yellow in calcareous soil. The chlorophyll and active iron (Fe2+) concentration of leaves was less in iron-efficient genotypes compared to efficient types in calcareous soil and reduction of both the parameters from noncalcareous to calcareous soil was considerably high in iron-inefficient lines. There was significant correlation between visual scores, chlorophyll and active iron content. There were no differences among F1s for iron chlorosis and they were all iron-inefficient. The frequency of iron-inefficient plants was higher than the efficient plants in all F2 populations. But most of the productive plants came from iron-efficient segregants indicating strong association between iron-efficiency and productivity. Based on the results selection for iron-efficiency in early generations and extensive evaluation for productivity in advanced generations is suggested for developing varieties for cultivation in calcareous soils. 相似文献
4.
Demet Tademir Ayegül Karaküük‐yidoan Mustafa Ulali Tuba Takin‐Tok Emne Eln Oru‐Emre Hasan Bayram 《Chirality》2015,27(2):177-188
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
5.
A kinetic analysis of the 5 alpha-reductases from human liver and prostate is presented. Human prostatic 5 alpha-reductase follows an ordered sequential mechanism in which NADPH binds first followed by testosterone. The order of release of products is DHT followed by NADP+. The apparent Km of prostatic 5 alpha-reductase for testosterone is 0.0339 +/- 0.006 microM, while the apparent Km for NADPH is 2.52 +/- 0.65 microM. Human liver 5 alpha-reductase also follows a sequential mechanism. The apparent Km of the liver enzyme is 0.110 +/- 0.08 microM; the apparent Km for NADPH is 6.2 +/- 0.6 microM. The fact that both the liver and prostatic 5 alpha-reductases have a sequential kinetic mechanism rules out the possibility that the reduction of testosterone to dihydrotestosterone involves an electron transport system as previously proposed. 相似文献
6.
Two new proteins with apparent molecular masses of 53 kDa and 190 kDa have been identified in both sarcoplasmic reticulum and human blood platelets using a monoclonal antibody, FII1b5. The sarcoplasmic reticulum FII1b5 antigens were present in the terminal cisternae fraction, but were absent from light sarcoplasmic reticulum. The platelet and skeletal muscle proteins were not sensitive to digestion with endoglycosidase H under conditions that removed carbohydrate from the 53 kDa glycoprotein in sarcoplasmic reticulum or GPIIIa in platelet microsomes and did not bind 45Ca in a nitrocellulose overlay calcium-binding assay. These results distinguished the FII1b5 antigens from the 53 kDa glycoprotein and calsequestrin of sarcoplasmic reticulum. The 190 kDa platelet and sarcoplasmic reticulum proteins were extracted from membranes with high concentrations of NaCl, indicating that the high molecular mass FII1b5 antigens are peripherally associated with the bilayers. In contrast, the platelet and muscle 53 kDa proteins remained membrane-bound in the presence of high salt concentrations, suggesting that they are integral proteins. 相似文献
7.
Akhlaq A. Farooqui Tahira Farooqui Allan J. Yates Lloyd A. Horrocks 《Neurochemical research》1988,13(6):499-511
Protein kinase C has recently attracted considerable attention because of its importance in the control of cell division, cell differentiation, and signal transduction across the cell membrane. The activity of this enzyme is altered by several lipids such as diacylglycerol, free fatty acids, lipoxins, gangliosides, and sulfatides. These lipids may interact with protein kinase C either directly or through calcium ions and produce their regulatory effect (activation or inhibition) on the activities of the enzymes phosphorylated by this kinase. These processes widen our perspective of the regulation of intercellular and intracelluular communication.Abbreviations used (PK-C)
Protein kinase C
- (cAMP-PK)
cAMP dependent protein kinase
- (DAG)
diacylglycerol
- (PtdSer)
phosphatidylserine
- (InsP
3)
inositol 1,4,5-trisphosphate
- (PtdIns 4,5-P2)
inositol 4,5 bisphosphate
- (FFA)
free fatty acid
- (MBP)
myelin basic protein
- (ATP)
adenosine triphosphate
- (GTP)
guanine triphosphate
- (TPA)
12-tetradecanoylphorbol-13-acetate
- (EGF)
epidermal growth factor
- (PDGF)
platelet derived growth factor
- (NeuNAc)
and N-acetylneuraminic acid 相似文献
8.
Autonomous DNA binding domains of lambda integrase recognize two different sequence families 总被引:35,自引:0,他引:35
The 40 kd lambda Integrase protein is shown to contain two autonomous DNA binding domains with different sequence specificities. Competition experiments in which the binding activity of Int is assayed through nuclease protection demonstrate the functional independence of the two DNA recognition specificities. Proteolytic cleavage of Int and footprinting analysis of the resulting two major peptides allow the physical separation and identification of two DNA binding domains: an amino-terminal peptide that interacts with "arm-type" sites and a carboxy-terminal peptide that binds to "core-type" sequences. In addition, the data suggest that the two domains can bind DNA simultaneously, consistent with a model in which Integrase would link two disparate DNA sequences. 相似文献
9.
Summary Snake flask experiments were carried out as a preliminary study of fat formation byTrichoderma
reesei (formallyviride) QM 9123 using a glucose based medium. The maximum quantity of fat production was 16% of the dry weight. The pH of the medium, as much as its composition, appeared to influence the quantity of fat that was produced. The fatty acids formed by the hydrolysis of the fats were found to be mainly unsaturated, with the 182 (linoleic) acid predominating. 相似文献
10.
R. Habib 《Plant and Soil》1988,108(2):267-274
A method is proposed for estimating the total length of a root system from sub-samples. This method is based on the measurement
of the length and diameter of small pieces of roots, and on the measurements of the bulk density of root sub-samples. It is
assumed that roots are cylinders with a given bulk density. The length and diameter of small root pieces are measured by image
analysis. A weighted quadratic mean (W.Q.M.) root diameter is then calculated and used in estimating the root length. This
W.Q.M. diameter is defined as the real mean diameter of an equivalent single root with the same length and volume as the tested
root system. The accuracy of prediction is demonstrated for one theoretical root system. The standard deviation of estimation
can be calculated using sampling simulations. 相似文献