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111.
The paper is concerned with the investigation of 52 patients who received i.v. thrombolytic therapy and "delayed" balloon dilatation of the coronary arteries in the first hours of acute myocardial infarction for the first 6 days. The investigation was repeated 6 mos after the onset of disease. Analysis of the coronaroventriculography results has shown that a combined use of i.v. thrombolytic therapy and delayed balloon dilatation of the coronary arteries results in a considerable and prolonged improvement of vascular permeability attended by a significant improvement of left ventricular local function and a decrease in the number of reocclusions. Infarction-related artery restenosis after combined therapy has little influence on left ventricular function which can be probably associated with a slow rate of its formation. Infarction-related vascular reocclusion leads to marked impairment of left ventricular total and local function. 相似文献
112.
Utilization of l-malic acid by yeast strain Hansenula anomala IGC 4380 is subject to glucose repression. Derepressed mutants were obtained with UV light by use of the nonmetabolizable glucose analog 2-deoxyglucose as a selective agent. Three mutant strains degraded l-malic acid in the presence of up to 30% (wt/vol) glucose and are of potential interest for the biological deacidification of grape must. The mutant strains, as compared with the parent strain, displayed inverse diauxy in glucose-malate medium, glucose being metabolized only after malate consumption had been completed. 相似文献
113.
Cysteine: Depolarization-Induced Release from Rat Brain In Vitro 总被引:3,自引:2,他引:1
Hans Jörg Keller Kim Quang Do Markus Zollinger Kaspar H. Winterhalter Michel Cuénod 《Journal of neurochemistry》1989,52(6):1801-1806
Compounds released on depolarization in a Ca2+-dependent manner from rat brain slices were screened to identify candidates for neuroactive substances. Lyophilized superfusates were analyzed by reversed-phase HPLC after derivatization with 9-fluorenyl N-succinimidyl carbonate. One of the compounds that showed an increase of concentration in superfusates in the presence of iodoacetamide was identified as the cysteine (Cys) derivative, S-carboxamidomethylcysteine, by fast atom bombardment mass spectrometry and other methods. This stable Cys derivative originates from endogenous, extracellular Cys. The finding led to a method for quantification of Cys in superfusates by immediate cooling of the superfusates to 0 degrees C and reaction of Cys with N-ethylmaleimide. Depolarization-induced Ca2+-dependent release of Cys was most prominent in the neocortex, followed by the mesodiencephalon, striatum, and cerebellum. This suggests that Cys is released from a neuronal compartment and might be involved in neurotransmission. 相似文献
114.
115.
Benzoxazinone kanamycin A conjugate. A new fluorescent probe suitable to detect mycoplasmas in cell culture 总被引:1,自引:0,他引:1
M Monsigny P Midoux C Depierreux C Bebear M T Le Bris B Valeur 《Biology of the cell / under the auspices of the European Cell Biology Organization》1990,70(3):101-105
The synthesis of a new benzoxazinone derivative suitable to detect early infection of cultured cells with mycoplasmas is described. p-[beta-(7-dimethylamino 1,4-benzoxazin 2-one 3yl)-vinyl]- phenylpropenoic acid was coupled to kanamycin A, an aminoglycoside leading to a cationic fluorescent probe which fluoresces at 600 nm upon excitation at 490 nm. This fluorescent probe is shown to heavily label the glycocallix of all the mycoplasma strains tested which are found to be associated with contaminated cultured cells and to allow an easy and rapid detection of contamination by fluorescence microscopy and flow cytometry. 相似文献
116.
D Le Guellec L Frappart R Willems 《Biology of the cell / under the auspices of the European Cell Biology Organization》1990,70(3):159-165
We have studied the expression of the fibronectin gene in 7 day-old chick embryo (stage 32) by in situ hybridization at the light and electron microscope levels, using a 397 base-pairs chicken cDNA, labeled by radioisotope or biotin-11dUTP. Cryostat sections of whole chick embryos displayed a selective label on the upper layer of the dermis, fibrous sclera and mesenchymal cells but not on cartilagenous sclera cells. These results show that the expression of the fibronectin gene varies in relation to the morphogenetic events. Hybridization at the ultrastructural level on thin sections of sclera embedded in Lowicryl K4M showed a selective labelling on various cell compartments. Biotin-11dUTP and radiolabeled probes were compared. The labeling was found precisely on the membrane of the rough endoplasmic reticulum and on the nuclear envelope. A few silver grains were located on the nucleus and in the perinucleolar region. This study shows that the postembedding in situ hybridization is a powerful procedure to study the expression of the extracellular protein genes and gives further information on the localization of mRNA. 相似文献
117.
Differential priming for endotoxin-induced circulating cytokine production by tumor necrosis factor-alpha and interleukin 1 beta 总被引:1,自引:0,他引:1
In unprimed mice, a single injection of a non-lethal dose of lipopolysaccharide (LPS) produced a rise in tumor necrosis factor (TNF) and interleukin 6 (IL 6) activities. Peak serum concentrations were attained, respectively, 1.5 hr and 2.5 hr after the challenge. Pretreatment with recombinant human TNF-alpha (rHuTNF) had a priming effect for enhanced production of both serum cytokines without any change in kinetics. The enhancement was more pronounced in the TNF (15-fold) than in the IL 6 (4-fold) response. Recombinant murine TNF caused a comparable increase in LPS-induced cytokine release. In contrast, comparable pretreatment with another macrophage-derived cytokine, recombinant human interleukin 1 beta (HuIL1-beta), revealed a negative effect on LPS-induced TNF release whereas IL 6 in the blood reached levels similar to those found after priming with rTNF. Moreover, when administered in combination with rHuTNF, rHuIL1-beta inhibited the priming effect on TNF autocrine production. 相似文献
118.
Abstract. South African mountain fynbos has been severely invaded by trees and shrubs introduced from other mediterranean-climate regions. Management of these invasions should involve controlling current invaders and screening future introductions. Invasion windows are described and functional groups are defined for pines based on life history attributes important for invasion in the fire-prone mountain fynbos. The most successful invasive pines here (Pinus halepensis, P. pinaster and P. radiata) are fire-resilient and have small seeds, low seed-wing loadings, short juvenile periods, moderate to high degrees of serotiny and relatively poor fire-tolerance as adults. Other species with these attributes, especially from mediterranean-climate regions, wouldbe high-risk introductions. Taxa in other functional groups have not become major weeds even with widespread man-aided dissemination. Experience with pine invaders was used to define functional groups in western Australian Banksia species (Proteaceae), shrubs and trees which include taxa with similar attributes to fynbos invaders (e.g. Hakea and Pinus spp.). Banksias have only recently been introduced to the Cape, and are likely to be increasingly cultivated for the cut flower market. Tall serotinous shrubs with many small seeds per plant, short juvenile periods and low fire tolerance were identified as high risk introductions. This group includes thicket-forming species which maintain very large viable seed banks, e.g. Banksia burdettii, B. hookeriana and B. leptophylla. Low sprouting shrubs with few large seeds per plant and long juvenile periods are unlikely to become invasive in mountain fynbos. The approach of defining functional groups based on life history attributes and invasion windows is valuable for predicting the probability of invasive success. Chance interactions suchas an opportunistic dispersal mutualism between Pinus pinea and an introduced squirrel sometimes confound these predictions and underscore the idiosyncracies inherent in biological invasions. 相似文献
119.
Résumé Les variations d'abondance des 2 cochenillesPhenacoccus manihoti Matile-Ferrero etFerrisia virgata Cockerell et des 2 prédateurs CoccinellidaeHyperaspis senegalensis hottentotta Mulsant etExochomus flaviventris Mader sont étudiées dans une parcelle de manioc.
La colonisation de cette dernière parE. flaviventris est précoce, en présence de faibles niveaux numériques des 2 proies, mais avec une dominance deF. virgata; celle d'H. s. hottentotta intervient un mois plus tard en relation semble-t-il avec la présence d'une population deP. manihoti abondante et jeune.
Nos observations font ressortir une dynamique des populations propre à chaque espèce de coccinelle, conditionnée par l'abondance
de l'une ou l'autre des proies, la structure des colonies de chaque cochenille et les conditions climatiques (température)
qui interviennent en synergie. Ainsi, la réponse numérique deH. s. hottentotta, plus forte que celle d'E. flaviventris, semble en relation plus étroite avecP. manihoti. PourE. flaviventris il appara?t difficile de séparer ce qui revient à chaque espèce de cochenille:F. virgata joue sans doute un r?le important pour son implantation dans les champs, puis sa raréfaction, mais c'est probablementP. manihoti qui permet l'augmentation de ses effectifs.
相似文献
120.
Sensory receptors of the ovipositor ofTrichogramma maidis are described. Sense organs are found on the 2nd valvifers (1 type), on the tip of the 3rd valvulae (2 types) and on the 1st valvulae (4 types). The nature and possible functions of these sensilla are discussed.
相似文献