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排序方式: 共有111条查询结果,搜索用时 15 毫秒
101.
Courtin F Huerre M Fyfe J Dumas P Boschiroli ML 《Journal of Feline Medicine and Surgery》2007,9(3):238-241
A 2-year-old, 4 kg, healthy, domestic shorthair female cat presented with ulcerated subcutaneous nodules on the commissures of its mouth. The cat was negative for feline leukaemia virus and feline immunodeficiency virus. Skin mycobacteriosis was diagnosed after detection of numerous acid-fast bacilli in Ziehl Neelsen-stained smears from the ulcers. Feline leprosy was suspected following preliminary polymerase chain reaction results: positive for Mycobacterium genus but negative for Mycobacterium tuberculosis and Mycobacterium avium complexes. Mycobacterium lepraemurium was later identified following DNA sequence analysis of the 5' end of the 16S rRNA gene and the 16S-23S internal transcribed spacer region. Microscopic lesions consisted of pyogranulomas containing mainly large foamy macrophages with 10-100 intra-cellular acid-fast bacilli per field. The cat was cured after surgery and a 14-week course of clofazimine (30 mg daily) and clarithromycin (50 mg twice daily). 相似文献
102.
103.
Summary Canopies of 22-year-old Santa Rosa plum trees irrigated with mini-sprinklers below the canopy with nonsaline (0.3 dS/m) water were sprayed weekly during one irrigation season with water having six levels of salinity (0.3, 1.1, 2.1, 3.3, 4.5, and 6.8 dS/m) to evaluate the extent of leaf injury, foliar absorption of Cl and Na, and yield response. Recognizable leaf injury was caused by spray water containing 29 mol/m3 of chloride and 15 mol/m3 of sodium. Severe leaf damage occurred when the leaf chloride and sodium concentrations exceeded 300 and 125 mmol/kg (dry weight), respectively. These concentrations were higher than those causing foliar damage on other trees in the same orchard which had been irrigated below the canopy with water having the same salinity as that sprayed on the canopy. No residual foliar injury was observed during the irrigation season following the year when the spray treatments were applied. Fruit yield measured six weeks after treatments were initiated was unaffected. In the following 2 years, yield was reduced by the highest salinity levels, even though the salt spray treatments were not continued and no foliar injury was visible. 相似文献
104.
Purification of a Low Molecular Weight Fucoidan for SPECT Molecular Imaging of Myocardial Infarction
Pierre Saboural Frédéric Chaubet Francois Rouzet Faisal Al-Shoukr Rana Ben Azzouna Nadia Bouchemal Luc Picton Liliane Louedec Murielle Maire Lydia Rolland Guy Potier Dominique Le Guludec Didier Letourneur Cédric Chauvierre 《Marine drugs》2014,12(9):4851-4867
Fucoidans constitute a large family of sulfated polysaccharides with several biochemical properties. A commercial fucoidan from brown algae, containing low molecular weight polysaccharidic species constituted of l-fucose, uronic acids and sulfate groups, was simply treated here with calcium acetate solution. This treatment led to a purified fraction with a yield of 45%. The physicochemical characterizations of the purified fucoidan using colorimetric assay, MALLS, dRI, FT-IR, NMR, exhibited molecular weight distributions and chemical profiles similar for both fucoidans whereas the sulfate and l-fucose contents increased by 16% and 71%, respectively. The biodistribution study in rat of both compounds labeled with 99mTc evidenced a predominant renal elimination of the purified fucoidan, but the crude fucoidan was mainly retained in liver and spleen. In rat myocardial ischemia-reperfusion, we then demonstrated the better efficiency of the purified fucoidan. This purified sulfated polysaccharide appears promising for the development of molecular imaging in acute coronary syndrome. 相似文献
105.
Takudzwa C. Madzivanzira Josie South Bruce R. Ellender Russell Chalmers Gethings Chisule Christine R. Coppinger Fernandu H. Khaebeb Francois J. Jacobs Machaya Chomba Bumango Musando Chanda Mwale Tamuka Nhiwatiwa Craig L. Rennie Naomi Richardson Olaf L. F. Weyl 《水产资源保护:海洋与淡水生态系统》2021,31(11):3156-3168
- Crayfish are invasive polytrophic keystone species, which are phylogenetically unique on the African continent. The Australian redclaw crayfish Cherax quadricarinatus is invasive in southern African freshwater systems including the Zambezi River Basin. Surveys conducted across the Zambezi Basin (Botswana, Zimbabwe, Namibia and Zambia) between 2017 and 2019 showed that C. quadricarinatus is broadly distributed across the Upper and Middle Zambezi and is rapidly spreading through natural and human-mediated means across several ecoregions.
- The probability of capture (Pcapture), catch per unit effort (CPUE) and population characteristics of C. quadricarinatus from the recent Barotse floodplain invasion were compared with older invasions from Lake Kariba and Kafue River.
- The Pcapture and CPUE of C. quadricarinatus in the recently invaded region of the Barotse floodplain were similar to those of the older invasions. Mass and carapace length of C. quadricarinatus from the Barotse floodplain were significantly lower than those of C. quadricarinatus from the older invasions. Sex ratios differed significantly between the three invasive populations. The Barotse floodplain population had a disproportionate investment in females (65.3%) and intersex individuals (8.4%). No crayfish were detected in the Zambezian Headwaters or the Okavango Floodplains ecoregions, but current spread rates are 49 km yr−1 downstream and 12 km yr−1 upstream.
- Investment in population management and the prevention of spread will have high conservation value across the invaded regions in order to restrict crayfish ecological impacts via direct predation and competition. In areas where crayfish are in high abundance, existing fisheries are affected through damage to nets, leading to increased net abandonment and ghost gear pollution in invaded regions.
- The emphasis should be on developing cohesive transboundary biosecurity policies in southern Africa to limit further spread that will threaten the integrity of freshwater ecosystems. However, long-term monitoring is needed to gauge invasion risk to sensitive areas such as the Okavango Floodplains ecoregion and determine field-based ecological impacts.
106.
Athale CA Dinarina A Mora-Coral M Pugieux C Nedelec F Karsenti E 《Science (New York, N.Y.)》2008,322(5905):1243-1247
During spindle assembly, chromosomes generate gradients of microtubule stabilization through a reaction-diffusion process, but how this is achieved is not well understood. We measured the spatial distribution of microtubule aster asymmetry around chromosomes by incubating centrosomes and micropatterned chromatin patches in frog egg extracts. We then screened for microtubule stabilization gradient shapes that would generate such spatial distributions with the use of computer simulations. Only a long-range, sharply decaying microtubule stabilization gradient could generate aster asymmetries fitting the experimental data. We propose a reaction-diffusion model that combines the chromosome generated Ran-guanosine triphosphate-Importin reaction network to a secondary phosphorylation network as a potential mechanism for the generation of such gradients. 相似文献
107.
Nguyen D Joshi-Datar A Lepine F Bauerle E Olakanmi O Beer K McKay G Siehnel R Schafhauser J Wang Y Britigan BE Singh PK 《Science (New York, N.Y.)》2011,334(6058):982-986
Bacteria become highly tolerant to antibiotics when nutrients are limited. The inactivity of antibiotic targets caused by starvation-induced growth arrest is thought to be a key mechanism producing tolerance. Here we show that the antibiotic tolerance of nutrient-limited and biofilm Pseudomonas aeruginosa is mediated by active responses to starvation, rather than by the passive effects of growth arrest. The protective mechanism is controlled by the starvation-signaling stringent response (SR), and our experiments link SR-mediated tolerance to reduced levels of oxidant stress in bacterial cells. Furthermore, inactivating this protective mechanism sensitized biofilms by several orders of magnitude to four different classes of antibiotics and markedly enhanced the efficacy of antibiotic treatment in experimental infections. 相似文献
108.
Estimates of terrigenous fluxes at three different water depths at two sites in the equatorial Atlantic by normalization against excess (230)Th flux indicate that the flux of terrigenous material to the seafloor was significantly higher during the last glacial period than it is today. Fluxes started to decrease during deglaciation and reached minimal values in the middle of the Holocene. From 15,000 to 5,000 years ago, there was a substantial increase in flux with increasing water depth below 2,800 meters; this increase may reflect resuspension and lateral transport of slope and rise sediment, possibly because of intensification of deepwater circulation during that period. 相似文献
109.
Andrianilana Fidelis Rasolo Francois Rakotonjanahary Roland Bienvenido O. Juliano Consuelo M. Perez J. C. Flinn B. B. Shahi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1990,40(1):21-30
A survey of rice in retail markets of Madagascar with emphasis on the surplus regions of Marovoay and Lac Alaotra and the deficient area, Antananarivo City showed rices of Madagascar to be predominantly medium-long, medium-shaped, with high apparent amylose content, low gelatinization temperature, and soft, hard or medium gel consistency. Mean protein content was 7.5%. Percent white grains among red and white grains ranged from 0 to 100% (mean 56%), head rice 0–94%, translucency 6–66% and Kett whiteness 12–48%. 相似文献
110.
Quoc Thinh Nguyen Caroline Douny Minh Phu Tran Francois Brose Phuong Thanh Nguyen Do Thi Thanh Huong Patrick Kestemont Marie‐Louise Scippo 《Aquaculture Research》2019,50(1):247-255
To develop an easy and reliable method for detecting pesticides and their residues in the Mekong Delta, a GC‐MS analytical method was developed and validated according to European guidelines (SANTE/11945/2015) for the determination of residues of three pesticides (quinalphos, trifluralin and dichlorvos) in water. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.002 and 0.007 μg/L, respectively, for quinalphos and trifluralin, and 0.016 and 0.053 μg/L, respectively, for dichlorvos and quinalphos. The repeatability, the within‐laboratory reproducibility as well as the trueness met the European criteria. The recovery rate ranged between 72% (for dichlorvos and quinalphos) and 82% (for trifluralin). The developed method was then applied for the analysis of 33 water samples, collected in April 2013, at the beginning of the rainy season in the Mekong Delta in Vietnam. Thirteen samples were from rice field, 10 were collected from cat fish ponds and from red tilapia cages. Results showed that only 9% of total water samples analysed contained residues of pesticides, but only in water from rice fish systems. From the 13 samples taken in these systems, quinalphos was detected in three samples. The other two pesticides were not detected. A comparison between analytical results obtained from GC‐MS and an alternative method, that is GC‐ECD indicated that GC‐ECD is less sensitive than GC‐MS, with LOQ ranging from 0.37 to 1.18 (depending on the pesticide). However, for samples with concentrations above these LOQ, no significant difference was observed between the results obtained from the two analytical methodologies. 相似文献