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51.
Anthrax is a serious disease caused by Bacillus anthracis. Humans can become infected by handling products from infected animals, by breathing spores and rarely by eating undercooked meat from infected animals. The genome of B. anthracis is highly monomorphic and thus shows very low DNA sequence variation. We analysed the molecular characteristics of 12 B. anthracis isolates from outbreaks in Croatia and Bosnia and Herzegovina, which have occurred during the past 10 years along with two vaccine strains. Genotyping system based on variable‐number tandem repeat analysis at six loci revealed that six isolates belong to genotype from the A1.a cluster whilst six isolates relate to the B2 cluster, compared to 89 previously described genotypes. The distribution of two evolutionarily distant clusters suggests an introduction of B. anthracis to this area in at least two separate events. 相似文献
52.
Stefancíková A Stĕpánová G Derdáková M Pet'ko B Kysel'ová J Cigánek J Strojný L Cisláková L Trávnicek M 《Veterinary research communications》2002,26(8):601-611
In the course of epizootological research on Lyme borreliosis in domestic and farm animals, the serological evidence for the occurrence of this zoonosis in cattle was screened. An ELISA showed that 25.2% of cattle from seven geographical areas in Slovakia were positive for anti-Borrelia IgG antibodies. In particular localities, the seroprevalence ranged from 0.6% to 34.3%. Of 33 cases with clinical signs, 20 ELISA-positive samples were also confirmed in Western blots. The most frequent clinical signs were lameness and swollen joints, but most of the cases were asymptomatic. The occurrence of Borrelia burgdorferi antibodies and suspected clinical signs in cattle of Slovak regions indicates that veterinarians should pay attention to this disease in their clinical practice and include it within the differential diagnosis. 相似文献
53.
Sheep complement (C) is haemolytic for sheep erythrocytes sensitized with rabbit antibody (sheep E-rabbit A) provided serum is used as soon as possible after collection. If left at 4 °C to separate from the clot, serum C activity for sheep E-rabbit A is markedly reduced. Heparinized plasma retains its haemolytic titre for at least 24 h at 4 °C. Plasma from Mg2+-ethyleneglycoltetraacetic acid (EGTA) blood is non-haemolytic, but addition of Ca2+ partially restores the titre. A high concentration of rabbit A is necessary to sensitize sheep E.Sheep C is haemolytic for human erythrocytes sensitized with sheep antibody (human E-sheep A) in the presence of Mg2+-EGTA. This C activity is stable at 4 °C for 24 h in serum, Mg2+-EGTA plasma and heparinized plasma. Haemolytic activity of serum heated at 50 °C for 30 min was restored by a factor B containing CM-cellulose fraction of foetal lamb serum in the presence of Mg2+-EGTA for human E-sheep A but not sheep E-rabbit A.These findings show that sheep C haemolysis of sheep E-rabbit A requires a Ca2+-Mg2+-dependent pathway that is labile in vitro for 24 h at 4 °C. 相似文献
54.
55.
Extract Because of the large range of neoplasms included in this report, a summary of all reports on the subject has not been attempted. References will be made only to those ovine neoplasms which have been reported from New Zealand. 相似文献
56.
Stefan Patzold Franz Michael Mertens Ludger Bornemann Britta Koleczek Jonas Franke Hannes Feilhauer Gerhard Welp 《Precision Agriculture》2008,9(6):367-390
Crop protection seldom takes into account soil heterogeneity at the field scale. Yet, variable site characteristics affect
the incidence of pests as well as the efficacy and fate of pesticides in soil. This article reviews crucial starting points
for incorporating soil information into precision crop protection (PCP). At present, the lack of adequate field maps is a
major drawback. Conventional soil analyses are too expensive to capture soil heterogeneity at the field scale with the required
spatial resolution. Therefore, we discuss alternative procedures exemplified by our own results concerning (i) minimally and
non-invasive sensor techniques for the estimation of soil properties, (ii) the evidence of soil heterogeneity with respect
to PCP, and (iii) current possibilities for incorporation of high resolution soil information into crop protection decisions.
Soil organic carbon (SOC) and soil texture are extremely interesting for PCP. Their determination with minimally invasive
techniques requires the sampling of soils, because the sensors must be used in the laboratory. However, this technique delivers
precise information at low cost. We accurately determined SOC in the near-infrared. In the mid-infrared, texture and lime
content were also exactly quantified. Non-invasive sensors require less effort. The airborne HyMap sensor was suitable for
the detection of variability in SOC at high resolution, thus promising further progress regarding SOC data acquisition from
bare soil. The apparent electrical conductivity as measured by an EM38 sensor was shown to be a suitable proxy for soil texture
and layering. A survey of arable fields near Bonn (Germany) revealed widespread within-field heterogeneity of texture-related
ECa, SOC and other characteristics. Maps of herbicide sorption and application rate were derived from sensor data, showing
that optimal herbicide dosage is strongly governed by soil variability. A phytoassay with isoproturon confirmed the reliability
of spatially varied herbicide application rates. Mapping areas with an enhanced leaching risk within fields allows them to
be kept free of pesticides with related regulatory restrictions. We conclude that the use of information on soil heterogeneity
within the concept of PCP is beneficial, both economically and ecologically. 相似文献
57.
Loose M Fischer-Friedrich E Ries J Kruse K Schwille P 《Science (New York, N.Y.)》2008,320(5877):789-792
In the bacterium Escherichia coli, the Min proteins oscillate between the cell poles to select the cell center as division site. This dynamic pattern has been proposed to arise by self-organization of these proteins, and several models have suggested a reaction-diffusion type mechanism. Here, we found that the Min proteins spontaneously formed planar surface waves on a flat membrane in vitro. The formation and maintenance of these patterns, which extended for hundreds of micrometers, required adenosine 5'-triphosphate (ATP), and they persisted for hours. We present a reaction-diffusion model of the MinD and MinE dynamics that accounts for our experimental observations and also captures the in vivo oscillations. 相似文献
58.
Gui Xiao Frances Nikki Borja Ramil Mauleon Jonas Padilla Mary Jeanie Telebanco-Yanoria Jianxia Yang Guodong Lu Maribel Dionisio-Sese Bo Zhou 《Rice》2017,10(1):37
Background
The rice Pi2/9 locus harbors multiple resistance (R) genes each controlling broad-spectrum resistance against diverse isolates of Magnaporthe oryzae, a fungal pathogen causing devastating blast disease to rice. Identification of more resistance germplasm containing novel R genes at or tightly linked to the Pi2/9 locus would promote breeding of resistance rice cultivars.Results
In this study, we aim to identify resistant germplasm containing novel R genes at or tightly linked to the Pi2/9 locus using a molecular marker, designated as Pi2/9-RH (Pi2/9 resistant haplotype), developed from the 5′ portion of the Pi2 sequence which was conserved only in the rice lines containing functional Pi2/9 alleles. DNA analysis using Pi2/9-RH identified 24 positive lines in 55 shortlisted landraces which showed resistance to 4 rice blast isolates. Analysis of partial sequences of the full-length cDNAs of Pi2/9 homologues resulted in the clustering of these 24 lines into 5 haplotypes each containing different Pi2/9 homologues which were designated as Pi2/9-A5, ?A15, ?A42, ?A53, and -A54. Interestingly, Pi2/9-A5 and Pi2/9-A54 are identical to Piz-t and Pi2, respectively. To validate the association of other three novel Pi2/9 homologues with the blast resistance, monogenic lines at BC3F3 generation were generated by marker assisted backcrossing (MABC). Resistance assessment of the derived monogenic lines in both the greenhouse and the field hotspot indicated that they all controlled broad-spectrum resistance against rice blast. Moreover, genetic analysis revealed that the blast resistance of these three monogenic lines was co-segregated with Pi2/9-RH, suggesting that the Pi2/9 locus or tightly linked loci could be responsible for the resistance.Conclusion
The newly developed marker Pi2/9-RH could be used as a potentially diagnostic marker for the quick identification of resistant donors containing functional Pi2/9 alleles or unknown linked R genes. The three new monogenic lines containing the Pi2/9 introgression segment could be used as valuable materials for disease assessment and resistance donors in breeding program.59.
M. Šrot 《Journal of pest science》1970,43(5):79-79
60.
Jonas DM 《Science (New York, N.Y.)》2003,300(5625):1515-1517