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31.
ABSTRACT

Selenium (Se) deficiency in Scandinavian soils is a common problem, and crops generally contain inadequate amounts to meet human need. This study shows a relationship of the Se concentration in spring wheat (Triticum aestivum L., c.v. ‘Helena’) and leaching water with timing of nitrogen (N) [as ammonium nitrate (NH4NO3)] and Se [as sodium selenate (Na2SeO4)] application. Ammonium-nitrate was applied by two methods (i) whole amount at sowing and (ii) in split application as 75% at sowing and 25% at stem elongation. Selenate was applied at cereal growth stages after sowing, e.g., tillering, stem elongation, head emergence, and milking. Split N application in comparison to one N application increased the grain protein content from 12.1 to 13.7 mg g? 1, and grain Se was increased from 0.8 to 1.1 mg kg? 1 when Se was applied at stem elongation and from 0.6 to 0.9 mg kg? 1 when applied at heading. The highest Se concentration in plant was achieved with the split N application and Se application at stem elongation or heading. Selenium leaching losses increased with increasing selenium concentration in the wheat grains. No differences in Se leaching losses were obtained with split N application. Applying selenate and ammonium-nitrate together after tillering increased the grain Se concentration, but did not affect the potential leaching of Se, and thus could be considered as an appropriate time of application of these elements.  相似文献   
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Genetic Resources and Crop Evolution - Lactuca indica L. is an undomesticated medicinal crop in the Asteraceae family. The study was carried out to identify elite genotypes for lettuce cultivation...  相似文献   
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Factors associated with the outcome of peritonitis in horses are seldom described. The objectives of this study were to determine the common clinical signs and clinicopathologic findings and to reveal prognostic factors associated with the outcome of peritonitis in equine patients. Data were examined in a retrospective manner in 55 horses diagnosed with and treated for peritonitis. The most common clinical and clinicopathologic findings were tachycardia (94%), increased amount of peritoneal fluid on ultrasound (84%), altered mucous membranes (82%), bacteria noted on the direct smear (67%), hyperfibrinogenaemia (58%) and left shift (40%). The most commonly isolated organism was E. coli (37%). Survival rates were as follow: 78% in the whole study, 81% in the abdominal lavage group, 93% in the medically and 46% in the surgically managed groups. Complications were more common in the non-survivor group (P < 0.001). Initial haematocrit and surgical interventions were strongly associated with non-survival in the multivariate logistic regression model (P = 0.049, OR: 1.07 and P = 0.01, OR: 9.87, respectively). Prognosis of peritonitis without gastrointestinal rupture depends on the initial hydration status, surgical interventions and development of secondary complications, while other clinical and clinicopathologic findings do not appear to correlate with survival. Prospective evaluation of hydration and perfusion parameters and abdominal lavage warrants further investigation.  相似文献   
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Here we report a case of canine babesiosis with unusual morphology of the causative agent. A male, seven-week-old Labrador retriever puppy, exhibiting severe anaemia and haemoglobinuria, was presented at the Clinic of Internal Medicine in February 2011. The puppy was euthanised. The most relevant pathological changes were icterus, severe splenomegaly, generalised lymphadenopathy and haemoglobin nephrosis. Samples were collected from various organs for histology within one hour post mortem. Impression smears were also prepared from the spleen after overnight storage at 4 °C. Tissue sections and smears showed the presence of multiple, coccoid intraerythrocytic bodies that measured 1-2 μm and resembled small babesiae. No large piroplasms were seen. DNA was extracted from the spleen, and a conventional PCR was performed for the amplification of a 450-bp region of the 18S rRNA gene of piroplasms. The causative agent was identified as Babesia canis canis, with 99% sequence identity to other European isolates. Sequence identity to B. gibsoni was only 91%. This is the first account to verify that the morphology of the large canine piroplasm, B. canis, can be uniformly small babesia-like post mortem or following the storage of tissue samples.  相似文献   
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Helianthus tuberosus agg., an herbaceous perennial plant from the Asteraceae family, is native to North America and was introduced as a crop to Europe in the seventeenth century. The status of this plant has been rather controversial in the Carpathian Basin. This paper reviews its taxonomy, chorology, and ethnobotany in this region, using data obtained from herbarium specimens, ethnobotanical surveys performed in Transylvania, and data published earlier, documenting the invasive features of the plant since the beginning of the nineteenth century. Our results suggest that (1) Helianthus tuberosus agg. has been present in the Carpathian Basin from the nineteenth century, (2) its taxonomy is problematic since the first part of the nineteenth century; (3) ethnobotanical surveys confirmed that the plant’s tuber has been locally used mostly as a food in Transylvania, collected from cultivation. Overall, Helianthus tuberosus agg. is both a ‘blessing and a curse’ at the same time, it is a valuable crop with beneficial nutritional value, and also an environmentally dangerous invasive element for the diversity of the flora of the Carpathian Basin.  相似文献   
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