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11.
A physical map of the 1-gigabase bread wheat chromosome 3B   总被引:2,自引:0,他引:2  
As the staple food for 35% of the world's population, wheat is one of the most important crop species. To date, sequence-based tools to accelerate wheat improvement are lacking. As part of the international effort to sequence the 17-billion-base-pair hexaploid bread wheat genome (2n = 6x = 42 chromosomes), we constructed a bacterial artificial chromosome (BAC)-based integrated physical map of the largest chromosome, 3B, that alone is 995 megabases. A chromosome-specific BAC library was used to assemble 82% of the chromosome into 1036 contigs that were anchored with 1443 molecular markers, providing a major resource for genetic and genomic studies. This physical map establishes a template for the remaining wheat chromosomes and demonstrates the feasibility of constructing physical maps in large, complex, polyploid genomes with a chromosome-based approach.  相似文献   
12.
Six tests for the detection of West Nile virus (WNV) antibodies in the serum of experimentally infected chickens were compared. The tests included the hemagglutination-inhibition test (HIT), immunoglobulin M (IgM)-capture enzyme-linked immunosorbent assay (ELISA) with WNV-infected mouse brain antigen, immunoglobulin G (IgG) indirect ELISA with tickborne encephalitis viral antigen, the microtitre virus neutralization test, the standard plaque reduction neutralization test (PRNT), and the microtitre PRNT (micro-PRNT). Thirty adult chickens, intravenously and intramuscularly inoculated with 107 plaque-forming units (PFU) of WNV strain Egypt 101, were bled and given a booster of 107 PFU at 7, 15, and 21 d postinoculation; the final blood collection was on day 28. Although the micro-PRNT is capable of detecting the highest antibody titres during both early and late infection, because of the technical complexity and time requirements of this test a combination of IgM and IgG ELISAs is recommended for serologic screening. Serum samples that give positive results in the ELISAs can then be tested by the micro-PRNT to determine the specificity of antibodies to WNV.  相似文献   
13.
A tick cell line derived from Dermacentor variabilis (RML-15) was inoculated with bovine RBC infected with Anaplasma marginale. Two hours after inoculation, numerous RBC were phagocytized by the tick cells. After one passage of the cell culture, numerous groups of Anaplasma-like particles were seen in the tick cell cytoplasm. Increased numbers of Anaplasma-like particles also were present. Seemingly, Anaplasma can multiply in tick cells.  相似文献   
14.
Citrus fruits were treated with wax coatings containing sodium 2-phenylphenate tetrahydrate (SOPP) and stored at 10 °C. No injuries appeared during 30 days' storage in Valencia oranges sprayed with waxes containing up to 4.75% of SOPP, or during 70 days' storage in Shamouti oranges and in grapefruit dipped in waxes containing up to 2.16% of SOPP. In Shamouti oranges and grapefruit dipped in waxes containing 3.1 to 3.88% of SOPP, injuries appeared at the beginning of storage. In non-injured fruits, the amounts of SOPP applied by waxing did not exceed 74.7 μg/cm2 of the fruit surface and the 2-phenylphenol (OPP) residues in the fruits did not exceed 36.8 parts/million; in injured fruits the amounts of SOPP applied varied between 105.1 and 211.3 μg/cm2 and the OPP residues between 41.5 and 123.6 parts/million. In non-injured fruit the amount of wax applied did not exceed 3.46 μl/cm2; in injured fruits the figure varied between 3.19 and 6.2 μg/cm2, suggesting that the wax coating concentrates at some places on the peel, causing injuries to the fruit. In injured grapefruit 7.93 μl/cm2 of wax was found on the injured part of the peel, and 3.21 μl/cm2 on the non-injured part, so that 124.6 μg of SOPP/cm2 corresponding to 61.6 parts/million of OPP in the fruit was applied to the fruit without causing injuries.  相似文献   
15.
Coagulase-negative staphylococci (CNS) are the most prevalent mastitis pathogens. However, virulence characteristics of CNS have not been well determined. The presence of genes for enterotoxins (sea-sej), toxic shock syndrome toxin-1 (tst), the exfoliative toxins (eta, etb), Panton–Valentine leukocidin (pvl) and mecA of CNS species isolated from cows and ewes with subclinical mastitis was investigated in this study. A total of 121 CNS (81 cows, 40 ewes) representing 18 different Staphylococci species were examined by PCR, and 38.1% (33 cows and 13 ewes) of CNS isolates had one or more se genes. The difference between percentages for SE toxin genes of CNS strains isolated from cows (40.7%) and ewes (32.5%) was not statistically significant (P > 0.05; χ 2 = 0.380). It was found that S. simulans isolates had the highest prevalent se genes. Furthermore, the most common SE gene types was seh-sej. In this study, none of the isolates harbored the toxic shock syndrome toxin gene (tsst) and the exfoliative toxin genes (eta, etb). Five cow (6.17%) and three ewe CNS (7.5%) isolates had mecA gene. Three cow (3.7%) and two ewe CNS (5.0%) isolates had pvl gene. In conclusion, the present study showed that CNS species isolated from cows and ewes could serve as potential reservoir of se, mecA, and pvl genes.  相似文献   
16.
This article analyses motivations and attitudes of small-scale forest owners in the Czech Republic towards joining associations. The research is a follow-up to a field investigation performed within the National Forest Programme II for 2007–2013 in the Vyso?ina region in 2010. The present research was carried out in the Pilsen region in 2012 and the Central Bohemia region in 2015, applying the same method of investigation as in 2010—a questionnaire survey. The findings are based on the results of all three surveys and supported by the analysis of legal and forestry-related documents concerning financial subsidies for forest owners’ associations. The study has revealed reluctance of small-scale owners to join associations. Their lack of motivation is caused by insufficient funding from the government supporting the administration and management of associations. The reluctance also results from the request for associations to be legal entities, which most applicants do not meet as they are either not registered or are registered under unsuitable legal forms. Between 2011 and 2013, no contributions were paid by the government to associations, and no new small-scale forest owners’ associations were formed. To increase associations, we propose that the government should provide sufficient funding not only for the administration and management of associations but also for the process of establishing associations and initial investments. It is also necessary to make major innovations in legislature regarding the transition of ownerships to more convenient legal forms.  相似文献   
17.
European Journal of Plant Pathology - In the past two decades, viruses in the genera Crinivirus and Begomovirus, transmitted by whiteflies, have emerged as threatening diseases to cucurbit...  相似文献   
18.
The health status of 200- to 400-year-old trees growing in an area alongside a road was described in detail on the basis of evaluation of hazard trees in urban areas and analyzed using the acoustic scanning and modified earth impedance (MEI) methods. Acoustic analysis was used to characterize tree trunks and coarse roots; MEI was used to characterize the active absorptive root surfaces (the electric impedance of soils and sapwood were also included). Several groups of trees were distinguished according to the extent of damage (slight, serious or extreme), which was easily detectable from the MEI results. It was confirmed that both methods gave similar results, which also corresponds to the detailed observations. Instrumental measurements provided additional information about trunk and root injuries, which cannot be directly observed. A combination of both methods is recommended to achieve the most reliable results. This unique approach is applicable for testing eventual threats by old ill trees for safety reasons over the landscape.  相似文献   
19.
The effects of resveratrol and pterostilbene (two structurally related stilbene compounds) on three human colon cancer cells were systematically compared. Cell viability tests indicated that IC(50) values of pterostilbene were 2-5-fold lower than those of resveratrol in all three cancer cells. Pterostilbene was also more potent in inhibiting colony formation of all three cancer cells. Annexin V/propidium iodide costaining assay and Western blotting analysis showed pterostilbene had a stronger apoptosis-inducing effect, which was evidenced by the higher percentage of annexin V positive cells and higher levels of cleaved caspase-3 and poly(ADP-ribose) polymerase proteins in cancer cells treated with pterostilbene compared with resveratrol. High-performance liquid chromatography analysis demonstrated that intracellular levels of pterostilbene were 2-4-fold higher than those of resveratrol after treatments with individual compounds at the same concentration. Overall, the results demonstrated that pterostilbene had more potent inhibitory effects on colon cancer cells than resveratrol, which may be associated with the superior bioavailability of pterostilbene to resveratrol.  相似文献   
20.

Background

The aim of the present study was to investigate biochemical and oxidative stress responses to experimental F. tularensis infection in European brown hares, an important source of human tularemia infections.

Methods

For these purposes we compared the development of an array of biochemical parameters measured in blood plasma using standard procedures of dry chemistry as well as electrochemical devices following a subcutaneous infection with a wild Francisella tularensis subsp. holarctica strain (a single dose of 2.6 × 109 CFU pro toto).

Results

Subcutaneous inoculation of a single dose with 2.6 × 109 colony forming units of a wild F. tularensis strain pro toto resulted in the death of two out of five hares. Plasma chemistry profiles were examined on days 2 to 35 post-infection. When compared to controls, the total protein, urea, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were increased, while albumin, glucose and amylase were decreased. Both uric and ascorbic acids and glutathione dropped on day 2 and then increased significantly on days 6 to 12 and 6 to 14 post-inoculation, respectively. There was a two-fold increase in lipid peroxidation on days 4 to 8 post-inoculation.

Conclusions

Contrary to all expectations, the present study demonstrates that the European brown hare shows relatively low susceptibility to tularemia. Therefore, the circumstances of tularemia in hares under natural conditions should be further studied.  相似文献   
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