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11.
Cristina Sánchez-Roldán Antonio Heredia Victoriano Valpuesta Martin J. Bukovac 《Journal of Plant Growth Regulation》1990,9(1-3):171-174
The indole-3-acetic acid (IAA) content in peach pericarp (Prunus persica L. Batsch cv. Merry) was highest at early stage I of development (200 ng/g fresh wt), decreased to the lowest level during stage II, and rose again at stage III to 60–70 ng/g fresh wt. High activity of glutamine synthetase was found in the pericarp during stage I. The soluble peroxidase activity was highest in the meso- and exocarp at stage II, and isoenzymatic changes in this fraction corresponded to the transition from cationic isoenzymes, predominant at stage I, to anionic isoenzymes at stage III. The ionically bound peroxidase activity in these tissues was highest at stage I. The three developmental stages showed marked differences in auxin content and enzyme activities; for peroxidases these changes reflect a developmental expression pattern for the isoenzymes. 相似文献
12.
Summary Phenotypic analyses of genetic combinations involving the gene extramacrochaetae (emc) reveal its participation in the differentiation of both sensory elements and wing veins. The study of near-amorphic alleles of emc in mitotitc recombination clones indicates that it also affects cell proliferation. These clones show abnormal sizes, shapes and spatial distribution. They differentiate extra sensory elements as well as extra veins. A gain of function mutation in the gene causes opposite phenotypes in both differentiation systems. The effects of the mutant on proliferation and patterning are consistent with the emc gene being involved in the transfer of information between neighbouring cells, which leads to the spatial expression of the achaetescute gene complex and genes involved in vein formation. 相似文献
13.
Antonio Gomez Sanchez Manuel Mancera Francisco Rosado Manuel Rico 《Carbohydrate research》1984,134(1):75-82
3,4,5,6,7-Penta-O-acetyl-1,2-dideoxy-1-nitro-d-gluco-hept-1-enitol reacts with methyl acetoacetate in an unusual Michael reaction, giving the normal adduct (6), and a bicyclic derivative (9) that arises from quasi-dimerization of the former when a high concentration of the base is used. Acetylation of compound 9 gives the hydroxylamine O-acetate (10).From the reactions of 3,4,5,6,7-penta-O-acetyl-1,2-dideoxy-1-nitro-d-galacto-hept-1-enitol with ethyl and tert-butyl acetoacetate, the normal adducts (7 and 8) were isolated. The structures of compounds 6 to 10 were established on the basis of their spectral properties (u.v., i.r., mass, and 1H- and 13C-n.m.r.) 相似文献
14.
Antonio G. Gonzalez Jaime Bermejo Barrera Francisco J. Tolfdo Marante 《Phytochemistry》1983,22(4):1049-1050
The fruit bodies of the Basidiomycete Scleroderma polyrhizum have been shown to contain the steroids ergosta-4,6,8(14) 22-tetraen-3-one and 5α,8α-epidoxyergosta-6,22-dien-3β-ol and also palmitic and oleic acids. 相似文献
15.
Facchiano Angelo; Facchiano Antonio; Facchiano Francesco; Ragone Raffaele; Colonna Giovanni 《Bioinformatics (Oxford, England)》1989,5(4):299-303
A flexible package designed to study protein structure is described.The package is devoted to the analysis of protein sequencesby drawing structural profiles of specific structure-relatedamino acid parameters. An Aminoacidic Parameters Data Bank (CHAMP)containing 32 different series of physico-chemical parametersof amino acids is available. Sequences can be loaded from anyASCII format data bank or from keyboard. The program possessesa routine which enables easy updating of the protein data bankand CHAMP Data Bank. FAST reads statistical correlations betweentwo plots in order to identify structural similarities. Plotscan be printed, saved or used for correlation, comparison orgraph overlap by using common spreadsheets (e.g. Lotus 123).Plots can be smoothed by a running mean or a running median.The program also has a special featurea global flexibilityanalysis of proteins. The package runs on IBM or compatiblesand requires DOS 3.0 or later.
Received on June 20, 1989; accepted on August 2, 1989 相似文献
16.
Antonio Balas Felix Garcia-Sanchez Fernando Gomez-Reino Jose L. Vicario 《Immunogenetics》1994,39(6):452-452
Correspondence to: J. L. Vicario. 相似文献
17.
Paula Tatiana Lopes Seixas Antonio Jacinto Demuner Luiz Claudio Almeida Barbosa Cristiane Isaac Cerceau Daiane Einhardt Blank Marcelo Henrique Dos Santos Elizeu de Sá Farias Marcelo Coutinho Picanço 《Journal of Applied Entomology》2023,147(2):116-125
Aedes aegypti L. (Diptera: Culicidae) is a vector for serious diseases in tropical regions. This pest is mainly controlled by commercial larvicides but the application of such products has led to environmental problems. Essential oils (EO) have been consistently reported as molecules with insecticidal activity and can be used to produce more environmentally friendly larvicides in the control of A. aegypti. In this study, the larvicidal effect of essential oils (EO) from the leaves of three Artemisia species was evaluated against A. aegypti. The oils were obtained from steam distillation and their chemical composition was determined by gas chromatography–mass spectrometry. The EO of Artemisia camphorata was the most active in the screening bioassay and presented LC50 and LC95 of 64.95 and 74.18 μg ml−1, respectively. In addition, we found that germacrene D-4-ol was the constituent responsible for the toxicity of this EO. Artemisia camphorata EO and its major constituent, germacrene D-4-ol, are promising for the development of natural larvicides against A. aegypti. 相似文献
18.
Antonio P. Linares Stuart H. Cohen Elliot Goldstein Alan D. K. Kelley Toby K. Eisenstein 《The Western journal of medicine》1984,141(2):203-205
Salmonella thompson, a common pathogen of poultry, has received scant attention as a cause of human gastroenteritis. At least 45 persons were infected with S thompson in Sacramento, California, after eating at a chicken restaurant and 38 became symptomatic. Ten required admission to hospital, and all were treated with antibiotics and improved. In 19 cases cultures of stool specimens for S thompson over a 60-day period showed slower but statistically insignificant differences in salmonellal elimination in 7 patients who received antibiotics when compared with 12 who were untreated. We report this outbreak to increase awareness of the virulence and prevalence of gastroenteritis due to S thompson. 相似文献
19.
Fatichenti Fabrizio Farris Giovanni Antonio Deiana Pietrino Ceccarelli Salvatore 《Applied microbiology and biotechnology》1984,19(6):427-429
Summary Fermentation tests in clearly defined laboratory conditions were carried out with eight functionally selected strains of Saccharomyces cerevisiae. Analysis of the data showed that there were no significant differences in malic acid production between the strains when the acid was initially present. When it was initially absent, however, significant differences were observed two strains (Nos. 1141 and 1083) showing marked productive superiority. With malic acid as the sole C source, two strains (Nos. 1109 and 1141) showed less acid consumption. 相似文献
20.
p-Hydroxyphenylglyoxal reacts with arginine residues in proteins to give a single product which can be quantitated spectrophotometrically. The reaction takes place under mild conditions, pH 7–9 and 25°C. Under these conditions up to complete modification of Nα-citraconyl-l-arginine was obtained within 60 min with less than 5% modification of other common amino acid side chains. The extent of modification in a protein can be determined at 340 nm using the molar absorption coefficient of 1.83 × 104m?1 cm?1 for the product at pH 9.0 and 25°C following removal of excess reagent by gel filtration. Several proteins, previously shown to have essential arginines, were modified by p-hydroxyphenylglyoxal and the losses in arginines were determined spectrophotometrically. These results were in close agreement with those of previous investigators. Rhea ovomucoid, a glycoprotein without arginines but containing an essential lysine, was relatively unaffected. 相似文献