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31.
Murphy WJ Larkin DM Everts-van der Wind A Bourque G Tesler G Auvil L Beever JE Chowdhary BP Galibert F Gatzke L Hitte C Meyers SN Milan D Ostrander EA Pape G Parker HG Raudsepp T Rogatcheva MB Schook LB Skow LC Welge M Womack JE O'brien SJ Pevzner PA Lewin HA 《Science (New York, N.Y.)》2005,309(5734):613-617
The genome organizations of eight phylogenetically distinct species from five mammalian orders were compared in order to address fundamental questions relating to mammalian chromosomal evolution. Rates of chromosome evolution within mammalian orders were found to increase since the Cretaceous-Tertiary boundary. Nearly 20% of chromosome breakpoint regions were reused during mammalian evolution; these reuse sites are also enriched for centromeres. Analysis of gene content in and around evolutionary breakpoint regions revealed increased gene density relative to the genome-wide average. We found that segmental duplications populate the majority of primate-specific breakpoints and often flank inverted chromosome segments, implicating their role in chromosomal rearrangement. 相似文献
32.
Cruz-Migoni A Hautbergue GM Artymiuk PJ Baker PJ Bokori-Brown M Chang CT Dickman MJ Essex-Lopresti A Harding SV Mahadi NM Marshall LE Mobbs GW Mohamed R Nathan S Ngugi SA Ong C Ooi WF Partridge LJ Phillips HL Raih MF Ruzheinikov S Sarkar-Tyson M Sedelnikova SE Smither SJ Tan P Titball RW Wilson SA Rice DW 《Science (New York, N.Y.)》2011,334(6057):821-824
The structure of BPSL1549, a protein of unknown function from Burkholderia pseudomallei, reveals a similarity to Escherichia coli cytotoxic necrotizing factor 1. We found that BPSL1549 acted as a potent cytotoxin against eukaryotic cells and was lethal when administered to mice. Expression levels of bpsl1549 correlate with conditions expected to promote or suppress pathogenicity. BPSL1549 promotes deamidation of glutamine-339 of the translation initiation factor eIF4A, abolishing its helicase activity and inhibiting translation. We propose to name BPSL1549 Burkholderia lethal factor 1. 相似文献
33.
The effects of canopy, soil physico-chemical and microbiological variables on Sclerotinia stem rot (SSR) on soybean were assessed in two soils (clay loam and sandy loam) using multiple regression and canonical redundancy analysis (RDA) and their partial form to control for the rotation (2 or 3-y-corn/soybean monoculture) and fertilization (mineral/urban compost) or spatial variables effects. The models revealed the minimal sets of variables that best explain the variance of the survival of Sclerotinia sclerotiorum’s sclerotia, carpogenic germination, disease severity and their associations. In clay loam, the 3-y-corn rotation reduced disease severity mainly through the reduction of weed biomass that favoured carpogenic germination. Urban compost has a conducive effect explained by a better soil surface drainage. Additionally, total N was found suppressive to sclerotial survival. In sandy loam, the carpogenic germination was negatively correlated with high C mineralization quotient and aggregate stability but correlated positively with Ca. Sclerotial survival was negatively correlated with pH and Ca, and positively correlated with biological fertility index. Aggregate stability, Ca and pH were associated with the urban compost. The regression and RDA analyses allowed to identify key variables that drived SSR development and explain their relationship with the cultural practices, soil health, as well as the spatial variation of disease variables. 相似文献
34.
L. Elizabeth Cruz-Ricque Jean Guillaume Gérard Cuzon AQUACOP 《Journal of the World Aquaculture Society》1987,18(4):209-217
The growth response to supplementation of mixed diets with a protein extracted from frozen squid (squid protein fraction: SPF) was tested at levels of 1.5, 3.0, 6.0 and 16.0% in the diet in four species of shrimp: Penaeus stylirostris, P. vannamei, P. monodon and P. indicus. In P. stylirostris and P. vannamei , growth rates were significantly improved by SPF even at the lowest level of supplementation. Improvement was obtained only with 6 and 16 percent in P. monodon , while no significant response was observed in P. indicus. The growth promoting effect of SPF at 16% of the diet could be explained by its nutritional value, particularly by its amino acid content, although all diets were supposed to be well balanced in all known nutrients. However, at lower levels the results obtained seemed to be due to the unknown growth factor (UGF) already mentioned in previous reports. 相似文献
35.
1. Guinea-fowl of both sexes and female chickens were fed from 1 to 12 weeks on diets the energy concentration of which was constant at either 2-6, 2-9 or 3-2 Mcal/kg (10-8, 12-1 or 13-4 MJ/kg) while the calorie to protein ratios were changed, for some groups, from 124 to 157 or 200 at 4 and 8 weeks. 2. Guinea-fowl, but not chickens, were unable to overconsume when the protein concentration was low with the result that the body fat content was not reduced when the protein concentration was increased. 3. In the second trial the ME level of the diets was fixed at 12-6 MJ/kg while the protein content was varied, from 21 to 28% in the diets fed to 6 weeks of age and from 15 to 24% in those fed from 6 to 12 weeks. 4. It is concluded that for the growing guinea-fowl the diet should contain 12-6 MJ ME/kg, the protein concentration reducing from 24 to 26% in the period 0 to 4 weeks to 19 to 20% in the period 4 to 8 weeks and to 16% or less in the period 8 to 12 weeks. 相似文献
36.
Picque D Lieben P Corrieu G Cantagrel R Lablanquie O Snakkers G 《Journal of agricultural and food chemistry》2006,54(15):5220-5226
Mid-infrared spectroscopy was applied to the analysis and discrimination of Cognacs and other distilled drinks (Armagnacs, whiskies, brandies, bourbons, rums, and counterfeit products). Strong correlations were found between dry extract spectra, polyphenolic dry extract spectra, and the total polyphenol concentration of samples, notably of Cognacs. Principal component analysis applied to spectral data made it possible to emphasize the importance of dry extract data when a distinction is made between Cognacs and Armagnacs, whiskies, bourbons, and rums, and of polyphenol concentration when Cognacs, brandies, and counterfeit products are separated. Ninety-six percent of samples in the test set were correctly assigned to Cognacs and non-Cognacs by partial least-squares discriminant analysis. 相似文献
37.
Jack‐Yves Deschamps Jean‐Michel Gaulier Guillaume Podevin Yan Cherel Nicolas Ferry Françoise A Roux 《Veterinary anaesthesia and analgesia》2012,39(6):653-656
Case history and presentationTwo non-human primates (Macaca fascicularis), weight 3.5 kg, enrolled in an experimental protocol received a 25 μg hour?1 transdermal fentanyl patch for postoperative analgesia. The following day both animals were clinically normal, but after a new induction of anaesthesia with ketamine, they developed severe and prolonged respiratory distress, profound coma and myosis.Management and follow-upAttempted reversal with naloxone was ineffective. After several hours of ventilation, both primates eventually died, 7 and 15 hours after ketamine injection, respectively. In both cases, the patch was discovered in the animal's cheek pouch. Subsequent fentanyl serum concentration measurements (8.29 and 14.80 μg L?1) confirmed fentanyl overdose.ConclusionsThis report of two fatal intoxications in non-human primates secondary to ingestion of a transdermal fentanyl patch demonstrates that this method of analgesia is inappropriate for non-human primates, because of their tendency to chew almost anything they can reach. 相似文献
38.
Drought and frost resistance of trees: a comparison of four species at different sites and altitudes
Katline Charra-Vaskou Guillaume Charrier Rémi Wortemann Barbara Beikircher Hervé Cochard Thierry Ameglio Stefan Mayr 《Annals of Forest Science》2012,69(3):325-333
Context
Drought and frost resistances are key factors for the survival and distribution of tree species. 相似文献39.
With the objective of controlling the day of ovulation, 40 mares were assigned to a control or three treated groups: A3d, A4d, and A5d. The treated groups received antarelix (Teverelix 0.01 mg/kg, i.v., twice a day) for 3, 4, or 5 days from the day the dominant follicle (F1) reached 28 mm (=D0), and one injection of hCG (1600 IU, i.v.) on D1, D2, or D3, respectively. Control mares received one injection of hCG when F1 reached 35 mm. Plasma LH, FSH, progesterone, and total estrogens were assayed. In the A3d, A4d, and A5d groups, 9 (90%), 6 (60%), and 5 (50%) out of 10 mares, respectively, ovulated on the expected day (i.e. between 24 and 48 h after hCG injection). In the control group, 7/10 (70%) presented the typical response to hCG. For 3 mares in both the A4d and A5d groups, the dominant follicle at the time the treatment was started did not ovulate and ovulation was postponed for between 11 and 15 days after the end of treatment. In the treated mares, the LH surge was abolished, and total estrogens were depressed during the preovulatory peak but the concentrations of FSH were not modified. Endocrine parameters were not altered in postponed cycles. Fertility did not differ in treated and control cycles. These results demonstrate that in mares: (1) ovulation can be programmed on a specific day of a 3-day period, with a success rate of 67%, by a treatment associating antarelix and one injection of hCG; (2) nevertheless in 20% of cases the dominant follicle regresses and does not ovulate; (3) for these mares ovulation is postponed by approximately 2 weeks; (4) terminal growth of the preovulatory follicle only requires low circulating concentrations of LH but atresia induced by a GnRH antagonist is significant when this treatment is administrated for more than 18 h. 相似文献
40.
Guillaume Lescuyer 《Small-Scale Forestry》2013,12(1):51-66
In Cameroon, community forests are frequently presented as a relevant option to increase the welfare of rural populations and simultaneously improve local governance and forest resources conservation. But apart from community forests, rural livelihoods also depend on forest areas, designated as ‘domestic forests’ in this article, where local users enjoy informal customary rights. The specific contributions of community and domestic forests to the evolution of the prevailing socio-ecological system are assessed through a diachronic study of a village which is located in southern Cameroon. The Sustainable Livelihoods Framework is used to compare the progress of this social-ecological system between January 2008 and December 2009. The overall evolution of livelihoods was found to be positive during that period. In this case study, domestic forests and community forests are based on complementary models, which are often observed in southern Cameroon. Domestic forests constitute the basis of socio-economic development, while community forests might offer opportunities for a local-level carbon sequestration payment mechanism. 相似文献