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排序方式: 共有858条查询结果,搜索用时 937 毫秒
81.
82.
Nazaret Hidalgo Giulia Mangiameli Teresa Manzano Galina G. Zhadan John F. Kennedy Valery L. Shnyrov Manuel G. Roig 《Biotechnology and Bioprocess Engineering》2011,16(4):821-829
The degradation and removal of a series of dyes used in the textile industry for polyester/wool (PES/WO) blends and present
in effluents, such as Green, Ash-Grey, Black, Navy Blue, Red and Yellow Domalan, and Orange and Red Bemacid, by catalytic
action, in the presence of H2O2, of extracts of a novel peroxidase from postharvest lentil stubble was investigated. The extracts of this peroxidase (LSP)
were effective in degrading these lastgeneration textile dyes, especially Green Domalan, Orange Bemacid, Grey and Black Domalan.
A sensitivity study was carried out for Green Domalan biodegradation to determine the effects of process parameters such as
pH, H2O2, enzyme and dye concentrations, contact and centrifugation times, and temperature. Standard ecotoxicity studies performed
with Vibrio fischeri revealed that the dye solutions treated with peroxidase and H2O2 were less ecotoxic than the untreated ones. 相似文献
83.
Lonardo E Hermann PC Mueller MT Huber S Balic A Miranda-Lorenzo I Zagorac S Alcala S Rodriguez-Arabaolaza I Ramirez JC Torres-Ruíz R Garcia E Hidalgo M Cebrián DÁ Heuchel R Löhr M Berger F Bartenstein P Aicher A Heeschen C 《Cell Stem Cell》2011,9(5):433-446
Nodal and Activin belong to the TGF-β superfamily and are important regulators of embryonic stem cell fate. Here we investigated whether Nodal and Activin regulate self-renewal of pancreatic cancer stem cells. Nodal and Activin were hardly detectable in more differentiated pancreatic cancer cells, while cancer stem cells and stroma-derived pancreatic stellate cells markedly overexpressed Nodal and Activin, but not TGF-β. Knockdown or pharmacological inhibition of the Nodal/Activin receptor Alk4/7 in cancer stem cells virtually abrogated their self-renewal capacity and in vivo tumorigenicity, and reversed the resistance of orthotopically engrafted cancer stem cells to gemcitabine. However, engrafted primary human pancreatic cancer tissue with a substantial stroma showed no response due to limited drug delivery. The addition of a stroma-targeting hedgehog pathway inhibitor enhanced delivery of the Nodal/Activin inhibitor and translated into long-term, progression-free survival. Therefore, inhibition of the Alk4/7 pathway, if combined with hedgehog pathway inhibition and gemcitabine, provides a therapeutic strategy for targeting cancer stem cells. 相似文献
84.
R.P. Bateman E. Hidalgo J. García C. Arroyo G.M. ten Hoopen V. Adonijah & U. Krauss 《The Annals of applied biology》2005,147(2):129-138
This article describes two field trials carried out at La Lola, Costa Rica, to assess control measures against frosty pod rot of cocoa (Theobroma cacao) caused by Moniliophthora (Crinipellis) roreri. In the first, factorial, trial the control agents were applied using motorised mistblowers (MMs) and hydraulic sprayers fitted with a narrow angle cone nozzle. There was an interaction between agents and application methods; together with previous application data for the most active fungicide (copper hydroxide), these trials indicate that best yields are achieved with sprays that maximise deposits on pods. We describe the droplet size spectra produced by a Stihl SR400 MM under a range of conditions because this has become the standard method of fungicide application in this series of trials at La Lola. The factor that had the largest effect on droplet size spectrum was the presence or the absence of a detachable baffle plate in front of the air‐shear nozzle. In both trials described here, MMs were fitted with baffle plates, a formulation pump and restrictor transmitting 550 mL min?1 to deliver an estimated equivalent of 190 L ha?1. Copper hydroxide as prophylactic applications at 1500 g a.i. ha?1 have, to date, shown the most consistent (but incomplete) improvement in healthy pod yield. Use of copper fungicides may be cost effective when farm‐gate cocoa prices exceed approximately $1.25 kg?1. In these trials, isolates of the hyperparasitic fungi Clonostachys byssicola and Trichoderma asperellum and two off‐patent triazole fungicides (bitertanol and triadimenol) made no significant improvement to healthy yields. The systemic oxathiin fungicide flutolanil, at a dosage of 300 g a.i. ha?1, appears to protect pods substantially at early stages but gives proportionately less control of M. roreri than copper at later stages of pod development. 相似文献
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Gascue C Mimbacas A Sans M Gallino JP Bertoni B Hidalgo P Cardoso H 《Human biology; an international record of research》2005,77(6):873-878
mtDNA Amerindian polymorphisms were studied in 108 inhabitants of Montevideo, Uruguay, using PCR RFLP analysis. Amerindian haplogroups were found in 20.4% of the sample. The frequency of Amerindian polymorphisms in Montevideo differed significantly from that observed in Tacuarembó, a city about 400 km away, indicating the high level of variation within Uruguay. Results for mitochondrial markers indicate that admixture occurred primarily as a result of Amerindian females mating with European males. 相似文献
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90.
Zhao M Hartke C Jimeno A Li J He P Zabelina Y Hidalgo M Baker SD 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,819(1):73-80
A rapid, sensitive and specific method was developed and validated using liquid chromatography-tandem mass spectrometry (LC/MS/MS) for determination of gefitinib in human plasma and mouse plasma and tissue. Sample preparation involved a single protein precipitation step by the addition of 0.1 mL of plasma or a 200 mg/mL tissue homogenate diluted 1/10 in human plasma with 0.3 mL acetonitrile. Separation of the compounds of interest, including the internal standard (d8)-gefitinib, was achieved on a Waters X-Terra C18 (50 mm x 2.1 mm i.d., 3.5 microm) analytical column using a mobile phase consisting of acetonitrile-water (70:30, v/v) containing 0.1% formic acid and isocratic flow at 0.15 mL/min for 3 min. The analytes were monitored by tandem mass spectrometry with electrospray positive ionization. Linear calibration curves were generated over the range of 1-1000 ng/mL for the human plasma samples and 5-1000 ng/mL for mouse plasma and tissue samples with values for the coefficient of determination of > 0.99. The values for both within- and between-day precision and accuracy were well within the generally accepted criteria for analytical methods (< 15%). This method was subsequently used to measure concentrations of gefitinib in mice following administration of a single dose of 150 mg/kg intraperitoneally and in cancer patients receiving an oral daily dose of 250 mg. 相似文献