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排序方式: 共有230条查询结果,搜索用时 15 毫秒
221.
Burgos-González Carlos Huerta-Aparicio Maricela Aguirre Virginio Vázquez Reyes Orihuela Agustín Pedernera Mariana 《Tropical animal health and production》2018,50(3):683-687
Tropical Animal Health and Production - The aim of the present study was to characterize milk production and preweaning development of lambs from Katahdin and Saint Croix sheep. Milk production was... 相似文献
222.
MAGIC Collaboration Albert J Aliu E Anderhub H Antonelli LA Antoranz P Backes M Baixeras C Barrio JA Bartko H Bastieri D Becker JK Bednarek W Berger K Bernardini E Bigongiari C Biland A Bock RK Bonnoli G Bordas P Bosch-Ramon V Bretz T Britvitch I Camara M Carmona E Chilingarian A Commichau S Contreras JL Cortina J Costado MT Covino S Curtef V Dazzi F De Angelis A De Cea Del Pozo E de Los Reyes R De Lotto B De Maria M De Sabata F Mendez CD Dominguez A Dorner D Doro M Errando M Fagiolini M 《Science (New York, N.Y.)》2008,320(5884):1752-1754
The atmospheric Cherenkov gamma-ray telescope MAGIC, designed for a low-energy threshold, has detected very-high-energy gamma rays from a giant flare of the distant Quasi-Stellar Radio Source (in short: radio quasar) 3C 279, at a distance of more than 5 billion light-years (a redshift of 0.536). No quasar has been observed previously in very-high-energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high-energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts. 相似文献
223.
A three‐year‐old male neutered domestic shorthair cat was presented for loss of vision associated with hyperthermia, lethargy and anorexia. Ophthalmic examination revealed a bilateral panuveitis. Cytological examination of aqueous and vitreous humours was performed and revealed a suppurative inflammation associated with numerous cocci. Enterococcus faecalis was identified by bacterial culture from aqueous and vitreous humour. No primary infection site was identified. Active uveitis resolved after systemic antibiotic therapy, but the vision loss was permanent. To the authors’ knowledge, this is the first reported case of endogenous bacterial endophthalmitis secondary to E. faecalis infection in a cat. 相似文献
224.
225.
Alisha Wehdnesday Bernardo Reyes Tran Xuan Ngoc Huy Son Hai Vu Hyun Jin Kim Jin Ju Lee Jeong Soo Choi John Hwa Lee Suk Kim 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(2)
BackgroundWe previously elucidated the protective mechanism of Korean red ginseng oil (RGO) against Brucella abortus infection, and our phytochemical analysis revealed that palmitic acid (PA) was an abundant component of RGO. Consequently, we investigated the contribution of PA against B. abortus.ObjectivesWe aimed to investigate the efficacy of PA against B. abortus infection using a murine cell line and a murine model.MethodsCell viability, bactericidal, internalization, and intracellular replication, western blot, nitric oxide (NO), and superoxide (O2-) analyses and flow cytometry were performed to determine the effects of PA on the progression of B. abortus infection in macrophages. Flow cytometry for cytokine analysis of serum samples and bacterial counts from the spleens were performed to determine the effect of PA in a mouse model.ResultsPA did not affect the growth of B. abortus. PA treatment in macrophages did not change B. abortus uptake but it did attenuate the intracellular survivability of B. abortus. Incubation of cells with PA resulted in a modest increase in sirtuin 1 (SIRT1) expression. Compared to control cells, reduced nitrite accumulation, augmented O2-, and enhanced pro-inflammatory cytokine production were observed in PA-treated B. abortus-infected cells. Mice orally treated with PA displayed a decreased serum interleukin-10 level and enhanced bacterial resistance.ConclusionsOur results suggest that PA participates in the control of B. abortus within murine macrophages, and the in vivo study results confirm its efficacy against the infection. However, further investigations are encouraged to completely characterize the mechanisms involved in the inhibition of B. abortus infection by fatty acids. 相似文献
226.
Twenty-one apple accessions were characterised and classified taxonomically with randomly amplified polymorphic DNA (RAPD). The results were compared with morphological and isoenzymatic classifications of the same material by calculating the congruence between similarity matrices. The results confirmed the greater discrimination capacity of RAPD compared with isoenzymes, although the taxonomic clusters obtained with both types of markers were congruent. The genetic relationships calculated using RAPD and isoenzymes showed little congruence with the morphological relationships among accessions. Isoenzymatic markers are useful in germplasm banks to evaluate the diversity of newly introduced accessions. The use of RAPD markers are especially beneficial to discriminate between material that is genetically similar, to evaluate genetic variability within a collection and to choose the components of the core collection. 相似文献
227.
Fermin Rivera Patricia Bonilla Sandra Soriano Jose Luis Reyes Fernando Lares Jesus Islas 《Water, air, and soil pollution》1987,32(3-4):397-406
A survey on Chromobacterium sp. and Flavobacterium sp. was conducted in a waste stabilization pond system at Santo Tomas Atzingo, State of Mexico. For this purpose methods for the isolation and identification of Chromobacterium sp. and Flavobacterium sp. from wastewater were developed and proved to be efficient. Such methods are the result of combining and modifying a series of previously reported techniques for this genera strains, but for environments different from wastewater. 相似文献
228.
G Orton JL Ortiz K Baines G Bjoraker U Carsenty F Colas A Dayal D Deming P Drossart E Frappa J Friedson J Goguen W Golisch D Griep C Hernandez W Hoffmann D Jennings C Kaminski J Kuhn P Laques S Limaye H Lin J Lecacheux T Martin G McCabe T Momary D Parker R Puetter M Ressler G Reyes P Sada J Spencer J Spitale S Stewart J Varsik J Warell W Wild P Yanamandra-Fisher G Fazio J Hora L Deutsch 《Science (New York, N.Y.)》1996,272(5263):839-840
Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile. 相似文献
229.
Brembs B Lorenzetti FD Reyes FD Baxter DA Byrne JH 《Science (New York, N.Y.)》2002,296(5573):1706-1709
Operant conditioning is a form of associative learning through which an animal learns about the consequences of its behavior. Here, we report an appetitive operant conditioning procedure in Aplysia that induces long-term memory. Biophysical changes that accompanied the memory were found in an identified neuron (cell B51) that is considered critical for the expression of behavior that was rewarded. Similar cellular changes in B51 were produced by contingent reinforcement of B51 with dopamine in a single-cell analog of the operant procedure. These findings allow for the detailed analysis of the cellular and molecular processes underlying operant conditioning. 相似文献
230.
Sierra-Alvarez R Yenal U Field JA Kopplin M Gandolfi AJ Garbarino JR 《Journal of agricultural and food chemistry》2006,54(11):3959-3966
Monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) are extensively utilized as pesticides, introducing large quantities of arsenic into the environment. Once released into the environment, these organo-arsenicals are subject to microbial reactions. Aerobic biodegradation of MMAV and DMAV has been evaluated, but little is known about their fate in anaerobic environments. The objective of this study was to evaluate the biotransformation of MMAV and DMAV in anaerobic sludge. Biologically mediated conversion occurred under methanogenic or sulfate-reducing conditions but not in the presence of nitrate. Monomethylarsonous acid (MMAIII) was consistently observed as an important metabolite of MMAV degradation, and it was recovered in molar yields ranging from 5 to 47%. The main biotransformation product identified from DMAV metabolism was MMAV, which was recovered in molar yields ranging from 8 to 65%. The metabolites indicate that reduction and demethylation are important steps in the anaerobic bioconversion of MMAV and DMAV, respectively. 相似文献