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21.
Agns Maisonneuve Isabelle Callebat Lydia Debordes Lucien Coppet 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,583(2)
A sensitive and specific capillary gas chromatographic method has been developed to measure trace amounts of 2,2′-dichlorodiethyl sulphide (sulphur mustard) in environmental or biological samples. Sulphur mustard was isolated from water or plasma by a solid-phase extraction procedure and from blood by liquid—liquid extraction. The accuracy and precision of the methods were demonstrated using replicate analyses of spiked water, plasma or blood: within-run and between-run variabilities were less than 20%. These analytical methods were used to evaluate the rate of sulphur mustard degradation in water or plasma. Good linear calibration curves, with a detection limit of 45 ng/ml, were obtained for quantitation and determination of sulphur mustard in blood following its intravenous administration to rats. Initial toxicokinetic data were obtained. 相似文献
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Hepatic δ-aminolevulinic acid synthetase was induced in rats injected with allylisopropylacetamide. The induction process was studied in relation to experimental perturbation of cytochrome P-450 in the liver. Animals were treated with either administered endotoxin or exogenous heme, both of which accelerate degradation of cytochrome P-450 heme. These manipulations were effective in blocking induction of δ-aminolevulinic acid synthetase, and the effect of each compound was proportional to its ability to stimulate degradation of cytochrome P-450 heme. The findings suggest that the heme moiety of cytochrome P-450 dissociates reversibly from its apoprotein and, prior to its degradation, mixes with endogenously synthesized heme to form a pool that regulates δ-aminolevulinic acid synthetase activity. A similar or identical heme fraction appears to mediate stimulation of heme oxygenase, which suggests that the regulation of δ-aminolevulinic acid synthetase and of heme oxygenase in the liver are closely interrelated. 相似文献
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P. Robert E. Castelli P.-C. Chung T. Chiroux C.F. Crispim-Junior P. Mallea F. Bremond 《IRBM》2013,34(2):186-190
Functional assessments are designed to ascertain a person's ability to perform activities of daily living (ADL) and provide valuable diagnostic as well as care-planning information. Currently, the gold standard for the assessment of functional ability involves clinical rating scales. However, scales are often limited in their ability to provide objective and sensitive information. In contrast, information and communication technologies (ICT) may overcome these limitations by capturing more fully the functional, as well as behavioral and cognitive disturbances associated with Alzheimer disease (AD). In this context, the ANR Tec San 2009 SWEET-HOME project aims at building an innovative framework for modeling ADL. The first result of the SWEET-HOME project has been the installation in a classical consultation setting of a specific room equipped with audio and video sensors. This leads to the following results: (1) physical activity recognition done by patients, (e.g., balance test, repeated transfers between sitting and standing): the monitoring system is able to detect the full set of activities with a detection rate varying from 96.9% to 100% (true positive rate); (2) activity of daily living: the monitoring system had an average sensitivity of 90% and an average precision of 83.51%. Using a functional score it is possible to differentiate AD patients from healthy controls; (3) acceptability of the system: results of the survey (all the 64 participants who accepted to be assessed using the system) indicated that the assessment has been perceived as pleasant (83%). 相似文献
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Summary The authors show that in certain isolated tissues (cornea of frog, mouse cancer) the mitotic processes continue during at least one hour. They are very strongly stimulated by heat and also by mitogenetic radiation. In the case of the cancer cells new mitoses are promoted in considerable number. A detailed analysis of both energy factors leads to the conclusion that they effect a disturbance of the unstable constellations (structures) of the elementary particles in the cell-body. Thus a certain degree of disorganisation of its plasma seems to stimulate cell-division. This statement is, in the opinion of the authors a proof that cell-division is controlled by a field, the trajectories of the elementary particles of the cell-body being a function of their coordinates relative to the cell-axes.
Résumé Les auteurs démontrent que dans certains tissus survivants (la cornée des yeux de grenouille et le cancer de souris) les mitoses continuent leur processus d'évolution durant au moins une heure. Par l'application de chaleur aussi bien que par l'irradiation mitogénétique on peut accélérer beaucoup le rhythme des mitoses en cours d'évolution et provoquer (dans les cas de cancer seulement) l'apparition d'un nombre considérable de nouvelles mitoses. L'analyse de l'action de ces deux facteurs d'énergie aboutit à la conclusion qu'il ne peut s'agir que d'un dérangement des constellations instables des éléments du corps cellulaire. On peut en déduire qu'un certain degré de désorganisation du plasme est favorable aux divisions cellulaires. En poursuivant et en développant cette conception, les auteurs arrivent à la conception du champ cellulaire de division, définissant les trajectoires des particules élémentaires comme fonction de ses coordonnés relativement aux axes des cellules.相似文献
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C. Shanker M. Mohan M. Sampathkumar Ch. Lydia G. Katti 《Biocontrol Science and Technology》2013,23(4):480-484
The diversity of natural enemies harboured by flowering forbs on rice field bunds was recorded. Ageratum conozoides with a maximum Shannon diversity index of 1.8 followed by Acmella uliginosa, Eclipta alba and Tridax procumbens are amenable for ecological engineering, providing nectar, pollen and alternate prey to natural enemies. 相似文献
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Dr. J. F. Castelli 《Plant Systematics and Evolution》1851,1(8):60-61
Ohne ZusammenfassungIn der Wienerzeilung vom 23. Juni 1843 ist eine Schilderung dieses Parkes von mir enthalten, allein seit 8 Jahren hat er sich so vervollkommnet, dass ich eine neue Beschreibung um so mehr für zweckmässig und willkommen halte, als diese auch in den gegenwärtigen Blättern mehr zur Kenntniss der Botaniker gelangt. Anmerk. des Aut. 相似文献
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Nicolas Tromas Zofia E. Taranu Mathieu Castelli Juliana S. M. Pimentel Daniel A. Pereira Romane Marcoz B. Jesse Shapiro Alessandra Giani 《Environmental microbiology》2020,22(4):1238-1250
Understanding how ecological traits have changed over evolutionary time is a fundamental question in biology. Specifically, the extent to which more closely related organisms share similar ecological preferences due to phylogenetic conservation – or if they are forced apart by competition – is still debated. Here, we explored the co-occurrence patterns of freshwater cyanobacteria at the sub-genus level to investigate whether more closely related taxa share more similar niches and to what extent these niches were defined by abiotic or biotic variables. We used deep 16S rRNA gene amplicon sequencing and measured several abiotic environmental parameters (nutrients, temperature, etc.) in water samples collected over time and space in Furnas Reservoir, Brazil. We found that relatively more closely related Synechococcus (in the continuous range of 93%–100% nucleotide identity in 16S) had an increased tendency to co-occur with one another (i.e. had similar realized niches). This tendency could not be easily explained by shared preferences for measured abiotic niche dimensions. Thus, commonly measured abiotic parameters might not be sufficient to characterize, nor to predict community assembly or dynamics. Rather, co-occurrence between Synechococcus and the surrounding community (whether or not they represent true biological interactions) may be a more sensitive measure of realized niches. Overall, our results suggest that realized niches are phylogenetically conserved, at least at the sub-genus level and at the resolution of the 16S marker. Determining how these results generalize to other genera and at finer genetic resolution merits further investigation. 相似文献