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61.
Amino acid composition of zein molecular components 总被引:1,自引:0,他引:1
Elisabetta Gianazza Vittorio Viglienghi Pier Giorgio Righetti Francesco Salamini Carlo Soave 《Phytochemistry》1977,16(3):315-317
Zein extracted from maize endosperm has been fractionated into four polypeptide chains, having the following MWs 23 000, 21 000, 13 500 and 9600. By amino acid analysis the two smaller MW chains (representing 30% of total zeins) have been found to be zein-type molecules. These two chains are thought to be responsible for zein granule formation via -S-S- bridges. Zein is also highly heterogeneous in charge, and is resolved into at least 15 components, with pI's in the pH range 5–9. As demonstrated by amino acid analysis, part of this heterogeneity is due to spot mutations in some of the genes responsible for zein synthesis. 相似文献
62.
63.
Green hydra with endosymbionts are smaller than brown asymbiotic ones. Regeneration experiments, mitotic index studies on algal and hydra tissue, and evidence for consumption and expulsion of algae are reviewed and it is suggested that larger green hydra have more difficulty controlling algal increase than smaller ones and that hydra have an upper size limit for maintenance of stable symbioses. A mathematical model is discussed which starts with simple physiological assumptions about hydra and generates field testable conclusions about how body and bud size, and reproductive rates depend on food particle size, quantity and temporal distribution. Unlike most analytic ecological-evolutionary models, this one integrates physiology, ecology and evolution without needing simplifying assumptions. 相似文献
64.
Barbara Frigo Lucio Scopsi Carlo Patriarca Franco Rilke 《Biotechnic & histochemistry》1991,66(3):159-166
A reliable and practical method is proposed for increasing sensitivity and detection efficiency of immunocytochemical techniques, based on silver enhancement of the nickel-diaminobenzidine product of the peroxidase reaction. The procedure produces a strong signal at the site of the end product of the peroxidase reaction which is visible as black grains at the light microscopic level. The method has been used to detect peroxidase labeled probes in immunocytochemical tissue preparations and blotting assays and is ideal for the purposes of double staining and photographic documentation. 相似文献
65.
A circular dichroism-based detection system presents several advantages in the HPLC analysis of chiral compounds because of the selective monitoring of optically active molecules. Its use allows reliable determination of enantiomeric excesses and elution order. To this end, the application of empirical, semiempirical, and nonempirical methods to get stereochemical information from the CD signal is reported. Furthermore, recording the CD spectra on line and evaluation of the dissymetry factor make the CD detection very powerful in characterizing the stereochemistry of chiral eluates. 相似文献
66.
Knowiedge on community structure of North Sea meiofauna has greatly increased recently. A quasisynoptic picture of meiofauna
densities and copepod community structure from 171 stations of the southern North Sea, sampled in April–May 1986, has been
obtained during the North Sea Benthos Survey. Latitudinal patterns in meiofauna abundance and copepod weight, abundance and
diversity exist in an area between 51°30′N and 58°30′N. Using TWINSPAN-classification five major groups of copepod species
can be recognized which are related to sediment type, latitude and depth. The part of the meiofauna in total benthic energy
flow, their role in the benthic food web and in biogeochemical cycles is discussed based on existing literature. There are
still considerable gaps in knowledge and the field is not progressing rapidly.
Publication no. 599 Netherlands Institute of Ecology, Centre for Estuarine and Coastal Ecology, Yerseke, The Netherlands. 相似文献
67.
Tiziano Fossati Simona Parisi Gianalfredo Abbiati Carlo Castiglioni 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,577(2)
A high-performance liquid chromatographic method for the determination of picotamide in human plasma and urine is described. After addition of an internal standard (bamifylline), the plasma and urine samples were subjected to liquid—liquid extraction and clean-up procedures. The final extracts were evaporated to dryness and the resulting residues were reconstituted in 100 μl of methanol—water (50:50, v/v) and chromatographed on a LiChrosorb RP-SELECT B reversed-phase column coupled to an ultraviolet detector monitored at 230 nm. Chromatographic analysis takes about 10 min per sample. The assay was linear over a wide range and has a limit of detection of 0.005 and 0.1 μg/ml in plasma and urine, respectively. It was selective for picotamide, accurate and robust and thus suitable for routine assays after therapeutic doses of picotamide. 相似文献
68.
Giuseppe Sancesario Carlo Cavallotti Dr. Francesco Amenta 《Cell and tissue research》1982,227(3):691-693
Summary The autonomic innervation of rat jugular vein was studied using glyoxylic acid fluorescence and acetylcholinesterase histochemical methods. The rat jugular vein is provided with both adrenergic and cholinergic nerve fibers organized in plexuses located at the adventitial-medial border. The existence of these nerve plexuses does not seem to support biochemical findings that suggest a lack of innervation in the rat jugular vein and which propose this blood vessel as a model for the analysis of drug-smooth muscle cell interaction without the interference of neuronal uptake mechanisms. 相似文献
69.
Carlo M. Ignoffo Clemente Garcia Michael J. Kroha 《Journal of invertebrate pathology》1982,39(2):198-202
The LD50 for larvae of Trichoplusia ni injected with blastospores of Nomuraea rileyi was 4.30 ± 1.16 hyphal bodies/larva; the LD50 for injected conidia was ca. 25,000 conidia/larva. The dose-mortality regression line for blastospores was Y = 4.6504 + 0.5487 X. Larval mortalities of Anticarsia gemmatalis and T. ni at 100 blastospores/larva were 0.4 ± 0.5% and 96.7 ± 1.9%, respectively. At a dosage of 25,000 conidia/larva, larval mortalities for A. gemmatalis and T. ni were 0.4 ± 0.5% and 43.1 ± 8.7%, respectively. Thus, larvae of A. gemmatalis were > 100 times and >200 times more resistant to injected conidia and blastospores, respectively, than were larvae of T. ni. Resistance of A. gemmatalis to N. rileyi may not be solely at the integumental barrier, as is often believed, but may also be a function of an internal physiological response. 相似文献
70.
Giacomino Randazzo Antonio Evidente Alberto Boccalatte Carlo Rossi 《Phytochemistry》1981,20(9):2177-2181
Measurement of isotope ratios in 1α,2α,3β-trihydroxy-p-menthane, which has been biosynthesized in Fusicoccum amygdali from 3H- and 14C-labelled mevalonate and in its degradation product diosphenol indicates that: (a) four tritium atoms arising from [5-3H2, 2-14C]MVA are retained, one more than suggested from the hydroxylation pattern, (b) menth-2-ene-1-ol is generated from an α-terpinyl cation through a 1,3-hydride shift and (c) trans-cleavage of an α-epoxide by hydrolysis gives 1α,2α,3β-trihydroxy-p-menthane. 相似文献