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851.
Thierry Gauquelin Valerie Bertaudiere Nicolas Montes Wadii Badri Jean-françois Asmode 《Biodiversity and Conservation》1999,8(11):1479-1498
Thuriferous juniper is only found in isolated parts of the western Mediterranean: France (Alps, Pyrenees and Corsican highlands), Spain, Algeria and Morocco. These semi-arid mountain stands, where thuriferous juniper trees grow in low-density open woodland, are seriously endangered: (i) In the Atlas mountains, the thuriferous juniper stands are heavily degraded as a result of the intensive wood removal and livestock activity in these densely populated areas. This situation, which will soon become irreversible unless remedial measures are urgently taken, has produced impoverished soils and hillside instability while contributing to desertification. (ii) In Spain, although livestock activity and cultivation have strongly reduced areas occupied by Juniperus thurifera, stands are still numerous and, in some regions, show a good regeneration due to conservation measures. (iii) In France, the decline in human and livestock activities over recent decades has led to a recolonization of some of the Juniper stands by pines or oak. A forest management system that enables these original stands to survive and regenerate must be undertaken without delay. The dynamics of evolution of these stands is quite different north and south of the Mediterranean. In both cases, conservation measures are urgently required to protect or rehabilitate these original stands with floristic, ecological and socio-economic interest. 相似文献
852.
A case of trisomy 9p in a family with translocation 9/15. 总被引:1,自引:0,他引:1
853.
Glycine betaine relieved sodium chloride-mediated inhibition of growth in Azospirillum lipoferum ATCC 29708. 35S-methionine labelling of proteins after salinity up-shock revealed strong induction of a 30 kDa protein which cross-reacted with the anti-glycine betaine binding protein antibody from Escherichia coli. This suggested that A. lipoferum had a salinity-induced ProU-like high-affinity glycine betaine transport system. A genomic library of A. lipoferum ATCC 29708 was screened for the proU-like gene by complementation of a proU mutant of E. coli. Four recombinant cosmids, capable of restoring growth of the proU mutant on plates containing 600 mM NaCl and 1 mM glycine betaine were selected. Selected recombinant cosmids hybridized with a proU gene probe from E. coli. Complementation of E. coli proU mutant with the A. lipoferum genomic DNA was evident by the ability of proU mutant (containing selected recombinant cosmids) to grow on minimal medium supplemented with 600 mM NaCl and 1 mM glycine betaine. 相似文献
854.
Magali Giacomoni Thierry Bernard Olivier Gavarry Sabine Altare Guy Falgairette 《European journal of applied physiology and occupational physiology》1999,80(6):591-597
Diurnal variations in ventilatory and cardiorespiratory responses to submaximal treadmill exercise were analysed in 11 eumenorrhoeic women and in 10 women using monophasic oral contraceptives. Subjects performed submaximal treadmill exercise at three intensities averaging 7, 8, and 9 km x h(-1), each for 4 min at 0800, 1300 and 1700 hours, assigned randomly on 3 separate days. Rectal temperature was measured before (T(rec(b))) and after (T(rec(a))) exercise. Cardiac frequency (f(c)), ventilation (V(E)), oxygen uptake (VO(2)), carbon dioxide output (VCO(2)), and respiratory exchange ratio (R) were assessed in the last minute of each stage of the exercise. Both T(rec(b)) and T(rec(a)) increased from 0800 to 1700 hours (P < 0.001). For a given submaximal work rate, VO(2) and VCO(2) were higher in the afternoon compared to the morning. Similarly, R was increased at 1700 hours compared to 0800 hours during the recovery period following exercise (P < 0.05). However, V(E) did not vary significantly during the day at any of the running intensities. No significant interactions (group x time of day) were observed in any of the studied parameters. In contrast to ventilation, the VO(2) and VCO(2) of the females during submaximal exercise were both affected by the time of day, without any differences between eumenorrhoeic women and users of oral contraceptives. 相似文献
855.
DNA Extraction from Activated Sludges 总被引:16,自引:0,他引:16
To optimize the cell lysis step for DNA extraction from activated sludge samples, two floc dispersion methods (sonication
versus stirring with a cation exchange resin), and three cell lysis treatments (lysozyme + SDS, sonication in a water bath,
and thermal shock) were tested. For dispersion, stirring with cation exchange resin was more efficient than sonication. The
cell lysis procedures were applied in two sequences, and DNA was quantified after each cell lysis treatment. Lysozyme + SDS
was the most effective step in the cell lysis procedures. The cell lysis treatment sequences giving the highest DNA yields
were not the same for all the sludges. The differences in sludge microbial compositions and floc structures required specifically
adapted cell lysis protocols. The proposed protocols were highly efficient for DNA extraction, yielding about 50 mg DNA g−1 volatile suspended solids, and allowed PCR amplification of 16S rDNA.
Received: 26 September 1998 / Accepted: 13 February 1999 相似文献
856.
857.
Developing Porphyra/salmon integrated aquaculture for bioremediation and diversification of the aquaculture industry 总被引:1,自引:0,他引:1
Thierry Chopin Charles Yarish Robert Wilkes Ellen Belyea Shan Lu Arthur Mathieson 《Journal of applied phycology》1999,11(5):463-472
For rapid growth and appropriate pigmentation,Porphyra requires the constant availability of nutrients, especially in summer when temperate waters are generally nutrient depleted.
Cultivation near salmon cages allows the alleviation of this seasonal depletion by using the significant loading of fishf
arms, which is then valued (wastes become fertilisers) and managed (competition for nutrients between desirable algal crops
and problem species associated with severe disturbances). Porphyra,being an extremely efficient nutrient pump, is an excellent candidate for integrated aquaculture for bioremediation and economic
diversification. Frequent harvesting provides for constant removal of significant quantities of nutrients from coastal waters,
and for production of seaweeds of commercial value. The production of P. yezoensis being limited in the Gulf of Maine, an assessment of the potential of seven native north-west Atlantic Porphyra species is presently in progress. To enable the production of conchospores for net seeding, the phenology of these species
and the conditions for their vegetative conchocelis exponential growth, conchosporangium induction, and conchospore maturation
were determined. The development of integrated aquaculture systems is a positive initiative for optimising the efficiency
of aquaculture operations, while maintaining the health of coastal waters.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
858.
859.
Thierry C. Vrain 《Journal of nematology》1999,31(4):424-436
Bioengineering strategies are being developed that will provide specific and durable resistance against plant-parasitic nematodes in crops. The strategies come under three categories: (i) transfer of natural resistance genes from plants that have them to plants that do not, to mobilize the defense mechanisms in susceptible crops; (ii) interference with the biochemical signals that nematodes exchange with plants during parasitic interactions, especially those resulting in the formation of specialized feeding sites for the sedentary endoparasites—many nematode genes and many plant genes are potential targets for manipulation; and (iii) expression in plant cells of proteins toxic to nematodes. 相似文献
860.
Laurence Lins Annick Thomas-Soumarmon Thierry Pillot Joël Vandekerckhove Maryvonne Rosseneu Robert Brasseur 《Journal of neurochemistry》1999,73(2):758-769
In a previous work, we predicted and demonstrated that the 29-42-residue fragment of beta-amyloid peptide (Abeta peptide) has in vitro capacities close to those of the tilted fragment of viral fusion proteins. We further demonstrated that apolipoprotein E2 and E3 but not apolipoprotein E4 can decrease the fusogenic activity of Abeta(29-42) via a direct interaction. Therefore, we suggested that this fragment is implicated in the neurotoxicity of Abeta and in the protective effects of apolipoprotein E in Alzheimer's disease. Because structurally related apolipoproteins do not interact with the Abeta C-terminal domain but inhibit viral fusion, we suggested that interactions existing between fusogenic peptides and apolipoproteins are selective and responsible for the inhibition of fusion. In this study, we simulated interactions of all amphipathic helices of apolipoproteins E and A-I with Abeta and simian immunodeficiency virus (SIV) fusogenic fragments by molecular modeling. We further calculated cross-interactions that do not inhibit fusion in vitro. The results suggest that interactions of hydrophobic residues are the major event to inhibit the fusogenic capacities of Abeta(29-42) and SIV peptides. Selectivity of those interactions is due to the steric complementarity between bulky hydrophobic residues in the fusogenic fragments and hydrophobic residues in the apolipoprotein C-terminal amphipathic helices. 相似文献