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381.
Veterinary Research Communications - A cross-sectional study was conducted in Colombia to recover Brucella spp. DNA from bovine whole-blood samples through probe-based real-time PCR (qPCR). By an...  相似文献   
382.
Rojas R  Doroteo V  Bustamante B  Bauer J  Lock O 《Fitoterapia》2004,75(7-8):754-757
The antimicrobial and free radical scavenging activity of the ethanol extract and fractions of Gentianella nitida have been assessed. The most susceptible microorganisms were Candida albicans, Trichophyton mentagrophytes and Microsporum gypseum. The antifungal activity was concentrated in the 90% methanol and nonsoluble fractions, while the radical scavenging activity was stronger in the ethyl acetate and nonsoluble fractions.  相似文献   
383.
Thiem B  Goślińska O 《Fitoterapia》2002,73(6):514-516
The antimicrobial activity of ethanolic and methanolic extracts of Solidago virgaurea herb from micropropagated plants and callus tissue was evaluated.  相似文献   
384.
Bacterial associations with plant roots are thought to contribute to the success of phytoremediation. We tested the effect of addition of a polycyclic aromatic hydrocarbon contaminated soil on the structure of the rhizosphere microbial communities of wheat (Triticum aestivum), lettuce (Lactuca sativa var. Tango), zucchini (Cucurbita pepo spp. pepo var. Black Beauty), and pumpkin (C. pepo spp. pepo var. Howden) 16S rDNA terminal restriction fragment length polymorphism (T-RFLP) profiles of rhizosphere microbial communities from different soil/plant combinations were compared with a pairwise Pearson correlation coefficient. Rhizosphere microbial communities of zucchini and pumpkin grown in the media amended with highest degree of contaminated soil clustered separately, whereas communities of these plants grown in unamended or amended with lower concentrations of contaminated soil, grouped in a second cluster. Lettuce communities grouped similarly to cucurbits communities, whereas wheat communities did not display an obvious clustering. The variability of 16S rDNA T-RFLP profiles among the different plant/soil treatments were mostly due to the difference in relative abundance rather than presence/absence of T-RFLP fragments. Our results suggest that in highly contaminated soils, the rhizosphere microbial community structure is governed more by the degree of contamination rather than the plant host type.  相似文献   
385.
There are few traceability systems other than genetic markers capable of distinguishing between sea products of different origin and quality. Here, we address the potential of stable isotopes combined with metabolic and growth parameters as a discriminatory tool for the selection of fish seeds with high growth capacity. For this purpose, sea bream fingerlings produced in three hatcheries (Spanish Mediterranean coast, MC; Cantabrian coast, CC; and South-Iberian Atlantic coast, AC) were subjected to isotopic analysis (δ15N and δ13C), and indices of growth (RNA and DNA) and energy metabolism [cytochrome-c-oxidase (COX) and citrate synthase (CS) activities] were calculated. These analyses were performed prior to and after a "homogenization" period of 35 days under identical rearing conditions. After this period, fingerlings were discriminated between hatcheries, with isotopic measures (especially δ15N), metabolic parameters (COX and CS), and proximal composition (fat content) in muscle providing the highest discriminatory capacity. Therefore, particular rearing conditions and/or genetic divergence between hatcheries, affecting the growth capacity of fingerlings, are defined mainly by the isotopic imprint. Moreover, the muscle isotopic signature is a more suitable indicator than whole fish for discrimination purposes.  相似文献   
386.
A serological survey was conducted in 2007 in the breeding goat population in Poland to gain insights into the epidemiology of pestivirus infection. All breeding herds were included in the study and representative serum samples were taken in each herd to evaluate herd-level seroprevalence at 10% expected individual-level prevalence and 95% level of confidence. Altogether 1060 serum samples from 49 herds were tested with blocking ELISA and then the positive and inconclusive results were confirmed in a serum neutralisation test, which also allowed us to determine the pestivirus species responsible for seroconversion. Herd-level seroprevalence proved to be 10.2% and bovine viral diarrhoea virus type 1 (BVDV-1) was responsible for the seroconversion in seven out of eight cases. In the remaining serum sample the causative virus could not be identified due to a pronounced cross-neutralising activity possibly derived from multiple infections. This is the first report on the diagnosis of BVDV-1 infection in Polish goats.  相似文献   
387.
In 2007 a survey on herd-level seroprevalence of Toxoplasma gondii and Neospora caninum infections in goats in Poland was carried out. Sera were collected from all 49 breeding goat herds, scattered over the entire country, with the vast majority of them located in the western, central and northern provinces. Only adult females (≥12 months of age) were included in the study. A herd was recorded as infected if at least one seropositive female was detected. In each herd, simple random sampling was applied and sample size was determined in a way, which allowed to evaluate serological status of a herd at expected individual-level seroprevalence 10% and level of confidence 95%. In total, 1060 sera were tested using two commercial indirect ELISA kits. Sera positive to N. caninum were subsequently confirmed with IFAT. The true herd-level seroprevalence was 100% for T. gondii and 9.0% for N. caninum infection. Three herds positive to T. gondii infection were randomly selected and all adult goats were tested with an ELISA. Individual-level true seroprevalence in these herds ranged from 30.2% to 100%. This is the first time that antibodies to N. caninum have been detected in goats in Poland.  相似文献   
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European Journal of Plant Pathology - To investigate the current status of viroid infection in potato fields in Russia, potato spindle tuber viroid (PSTVd) and chrysanthemum stunt viroid (CSVd)...  相似文献   
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