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112.
This article focuses on anthropometric parameters as height for age, weight for age and weight for height, which are among the most used tools for assessing well-being of infants and children. Such data have been collected between 1992--1993 from samples of infants and children aged between 2 and 10 years from urban and rural areas of Ethiopia. Similar to many other reports from developing countries the great amount of malnourished children is preoccupying as reflected by about 15% of children below the 5th centile of weight for height and about 53% of children below the 5th centile of height for age and about 45% below the 5th centile of weight for age. 相似文献
113.
Tremetsberger K Weiss-Schneeweiss H Stuessy T Samuel R Kadlec G Ortiz MA Talavera S 《Molecular phylogenetics and evolution》2005,35(1):102-116
Hypochaeris has a disjunct distribution, with more than 15 species in the Mediterranean region, the Canary Islands, Europe, and Asia, and more than 40 species in South America. Previous studies have suggested that the New World taxa have evolved from ancestors similar to the central European H. maculata. Based on internal transcribed spacer (ITS) sequences and fluorescence in situ hybridization (FISH) with 5S and 18S-25S rDNA of the previously overlooked Hypochaeris angustifolia from Moyen Atlas, Morocco, we show that it is sister to the entire South American group. A biogeographic analysis supports the hypothesis of long-distance dispersal from NW Africa across the Atlantic Ocean for the origin of the South American taxa rather than migration from North America, through the Panamian land bridge, followed by subsequent extinction in North America. With the assumption of a molecular clock, the trans-Atlantic dispersal from NW Africa to South America is roughly estimated to have taken place during Pliocene or Pleistocene. 相似文献
114.
Fibronectin (FN) is a multifunctional extracellular matrix glycoprotein, which participates in cell migration and signalling to adhering cells. Due to alternative splicing and post-translational modifications, different isoforms of FN are generated by a wide variety of cells. T lymphocytes synthesize a surface-associated isoform of FN, containing the two 'extradomains' EDA and EDB. In the present study, we identified gangliosides within the T-cell membrane as specific binding sites for the N-terminal 30 kDa fragment of FN. When T cells were activated with anti-CD3 coated beads, FN, together with the ganglioside GM1, converged at the contact zone. Moreover, endogenous FN was present in the detergent insoluble microdomain. The function of FN in T cells is still under investigation; however, its presence together with gangliosides at the activation site suggests participation in T-cell signalling. 相似文献
115.
Amino acid contents and transport in oilseed rape (<Emphasis Type="Italic">Brassica napus</Emphasis> L.) under different nitrogen conditions 总被引:1,自引:0,他引:1
Oilseed rape (Brassica napus L.) needs very high nitrogen fertilizer inputs. Significant amounts of this nitrogen are lost during early leaf shedding and are a source of environmental and economic concern. The objective of this study was to investigate whether the remobilization of leaf amino acids could be limiting for nitrogen use efficiency. Therefore, amino acid concentrations were analyzed in subcellular compartments of leaf mesophyll cells of plants grown under low (0.5 mM NO3–) and high (4 mM NO3–) nitrogen supply. With high nitrogen supply, young leaves showed an elevated amino acid content, mainly in vacuoles. In old leaves, however, subcellular concentrations were similar under high and low nitrogen conditions, showing that the excess nitrogen had been exported during leaf development. The phloem sap contained up to 650 mM amino acids, more than four times as much than the cytosol of mesophyll cells, indicating a very efficient phloem-loading process. Three amino acid permeases, BnAAP1, BnAAP2, and BnAAP6, were identified and characterized. BnAAP1 and BnAAP6 mediated uptake of neutral and acidic amino acids into Xenopus laevis oocytes at the actual apoplastic substrate concentrations. All three transporters were expressed in leaves and the expression was still detectable during leaf senescence, with BnAAP1 and BnAAP2 mRNA levels increasing from mature to old leaves. We conclude that phloem loading of amino acids is not limiting for nitrogen remobilization from senescing leaves in oilseed rape. 相似文献
116.
An image based two-dimensional (2-D) reference map of very alkaline yeast cell proteins was established by using immobilized pH gradients (IPG) up to pH 12 (IPG 6-12, IPG 9-12 and IPG 10-12) for 2-D electrophoresis and by using matrix-assisted laser desorption/ionization-time of flight mass spectrometry peptide mass fingerprinting for spot identification. Up to now 106 proteins with theoretical isoelectric points up to pH 11.15 and molecular mass between 7.5 and 115 kDa were localized and identified. Additionally, due to the improved resolution of steady-state isoelectric focussing with IPGs, even low copy number proteins with codon bias below 0.02 were detected and identified. 相似文献
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118.
Gertrud Kolb 《Zoomorphology》1986,106(4):244-246
Summary The ommatidia in the two dorsal rows at the rim of the eye of Aglais urticae differ from all the other ommatidia of the large dorsal area, in rhabdom structure, length, and configuration of the ninth retinula cell. The type of rhabdom in this dorsal rim zone provides the structural prerequisites for the reception of polarized light; functional subdivision of the retina into two parts is indicated. 相似文献
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120.
Rebekka Harting Jessica Starke Harald Kusch Stefanie Pöggeler Isabel Maurus Rabea Schlüter Manuel Landesfeind Ingo Bulla Minou Nowrousian Ronnie de Jonge Gertrud Stahlhut Katharina J. Hoff Kathrin P. Aßhauer Andrea Thürmer Mario Stanke Rolf Daniel Burkhard Morgenstern Bart P. H. J. Thomma James W. Kronstad Susanna A. Braus-Stromeyer Gerhard H. Braus 《Molecular Plant Pathology》2021,22(8):939-953