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Ralstonia solanacearum is a known bacterial pathogen of eucalypt and potato plants in Africa. A survey was undertaken to detect this pathogen in eucalypt plantations in South Africa, the Democratic Republic of Congo, and Uganda. Numerous bacterial strains were isolated from trees with symptoms typical of bacterial wilt, but only seven were positively identified as R. solanacearum. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique, based on the hrp (hypersensitive response and pathogenicity) gene region was used to determine and group the biovars of these R. solanacearum strains. The eucalypt isolates and one potato isolate formed a biovar 3 cluster, whereas the two other potato isolates formed a cluster that corresponded to biovar 2. Amplified fragment length polymorphism (AFLP) analysis confirmed these clusters. Therefore, PCR-RFLP can be used as a reliable diagnostic technique to enable researchers to rapidly identify the pathogen.  相似文献   
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Chronic bleeding due to extensive haemorrhage from a ruptured corpus haemorrhagicum developed 2–4 weeks after parturition and was identified as the cause for a haemoperitoneum in a 7‐year‐old Shetland Pony mare, leading to anaemia. Diagnosis was made upon exploratory coeliotomy and a unilateral ovariectomy was performed. Intra‐ and post operatively, the mare received autologous blood transfusions of noncitrated blood. To our knowledge, this is the first report of an autologous blood transfusion accomplished using noncitrated blood collected from the abdominal cavity.  相似文献   
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Uittreksel

Die bogrondse groei van Medicago truncatula, cvv. Cyprus en Jemalong, M. aculeata var. inermis, cv. SA 4438, M. orbicularis, pv. SA 2552 en M. rugosa, cv. Paragosa, afkomstig van ‘n besproeide veldproef, is vir ruproteïen en vir in vitro‐ verteerbaarheid ontleed. Die betrokke genotipes is op drie verskillende plantdatums, c. 30 dae gespasieer, van einde Februarie tot einde April, gevestig, en die gedroogde materiaal wat aan die begin van blomstadium en met die aanvang van peulverkleuring versamel is, is ontleed.

Met blom het die proteïeninhoud gewissel van 12,8% by Paragosa, wat swak genoduleerd was, tot 27,9% by SA 2552. Die gemiddelde was 21,3%. Op die peulverkleurstadium was die gemiddelde 15,2%, met ‘n wisseling van 8,5% by Paragosa tot 19,4% by SA 4438. Planttyd het feitlik geen invloed op die persentasie gehad nie. Wat proteïen‐produksie betref, was daar, met die uitsondering van Paragosa, ‘n duidelike positiewe verband tussen groeiperiode en hierdie parameter. SA 4438 met 2,3t/ha het die hoogste proteïenopbrengs op die peulverkleurstadium gelewer.

Die afgeleide verteerbaarheid op die blomstadium was gemiddeld 77,4%, met ‘n wisseling van 75,1% by SA 2552 tot 80,6% by Paragosa. Met peulverkleuring was die gemiddelde 67,9%, met ‘n wisseling van 64,9% by Cyprus tot 70,0% by SA 2552. Die invloed van plantdatum was gering.  相似文献   
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Biofumigation is considered a good alternative to chemical fumigation because it can control crop pathogens and diseases with lower health and environmental risks than chemical fumigants. Glucosinolates are volatile compounds found in most Brassica species, and when hydrolysed, it forms a range of natural toxins including isothiocyanates that act as biofumigants. However, the effect of glucosinolates and their breakdown products on non-target and beneficial soil organisms is not well documented. Three biofumigants, broccoli, mustard and oilseed radish, were evaluated for their effect on earthworms (Eisenia andrei) and the soil microbial community. Sub-lethal endpoints, including growth and reproductive success of the earthworms, were monitored. Genotoxicity of the biofumigants towards earthworms was evaluated by means of the comet assay. Broccoli reduced earthworm reproduction while mustard induced more DNA strand breaks in earthworm cells compared to the control. Soil microbial community function and structure were evaluated by means of community level physiological profiling and phospholipid fatty acid analyses. The effects exerted by the biofumigants on the microbial community were the most pronounced within the first 14 days after application. Carbon substrate utilisation was most affected by the oilseed radish treatment and microbial community structure by the mustard treatment.  相似文献   
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Neoplasia is a rare cause of ataxia in horses. This report describes a 2-year-old colt presented with sudden-onset ataxia in which a cervical vertebral osteosarcoma causing severe compression of the spinal cord was diagnosed. Radiological changes included a large osteolytic lesion in the vertebral body, the vertebral arch, the right cranial articular process and the right transverse process of C4, interrupting the borders of the vertebral foramen and the right transverse foramen. Myelography revealed a marked spinal cord compression. Necropsy confirmed the presence of a well-demarcated, invasive and firm mass protruding from the fourth cervical vertebral body that led to severe compression of the spinal cord. In spite of its strongly pleomorphic nature, the detection of osteoid confirmed the diagnosis of a central osteosarcoma of the combined type. To the best of our knowledge, a primary single vertebral osteosarcoma causing ataxia in a juvenile horse has not previously been reported, and findings of this case report could help in the diagnostic work-up of similar cases.  相似文献   
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Observations of core-diffracted P (Pdiff) and SH (SHdiff) waves recorded by the Missouri-to-Massachusetts (MOMA) seismic array show that the ratio of compressional (P) seismic velocities to horizontal shear (SH) velocities at the base of the mantle changes abruptly from beneath the mid-Pacific (VP/VS = 1.88, also the value predicted by reference Earth models) to beneath Alaska (VP/VS = 1.83). This change signifies a sudden lateral variation in material properties that may have a mineralogical or textural origin. A textural change could be a result of shear stresses induced during the arrival at the core of ancient lithosphere from the northern Pacific paleotrench.  相似文献   
19.
A persistent reversal in the expected polarity of the initiation of vertically polarized shear waves that graze the D' layer (the layer at the boundary between the outer core and the lower mantle of Earth) in some regions starts at the arrival time of horizontally polarized shear waves. Full waveform modeling of the split shear waves for paths beneath the Caribbean requires azimuthal anisotropy at the base of the mantle. Models with laterally coherent patterns of transverse isotropy with the hexagonal symmetry axis of the mineral phases tilted from the vertical by as much as 20 degrees are consistent with the data. Small-scale convection cells within the mantle above the D' layer may cause the observed variations by inducing laterally variable crystallographic or shape-preferred orientation in minerals in the D' layer.  相似文献   
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