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排序方式: 共有73条查询结果,搜索用时 171 毫秒
21.
Lauri V. Punto MD ScD DVM PhD Timo O. Nevalainen DVM MS Sirkka A. Wiljasalo MD ScD Ilkka V. O. Alitalo DVM PhD 《Veterinary radiology & ultrasound》1984,25(1):43-45
A dog with aspiration pneumonia was examined by computed tomography (CT) with 8-mm continuous scans of the chest. The results demonstrated that CT is a useful procedure for evaluating pneumonia, although high cost prevents its routine use. A normal littermate was examined, and normal structures of the chest and chest wall were compared. 相似文献
22.
Marjatta Kärkkäinen DVM Drmedvet Matti Mero DVM MD Pentti Nummi MSc Lauri Punto DVM MD 《Veterinary radiology & ultrasound》1991,32(2):71-74
Magnetic resonance (MR) imaging is a relatively new method of medical imaging. MR studies on the normal canine central nervous system were performed using a low field MR scanner. The regions of interest were the head, neck, and lumbar region. The MR findings in two patients with brain atrophy and cervical neck disc protrusion were also evaluated. Based on our findings it appears that low-field scanners will be satisfactory for use in veterinary diagnostic imaging. 相似文献
23.
Pirjo Peltonen-Sainio Arjo Kangas Yrj Salo Lauri Jauhiainen 《Field Crops Research》2007,100(2-3):179-188
Multi-location data collected over 30 years in Finland on major cereal crops (spring barley, oat and wheat, and winter wheat and rye) provide an opportunity to characterise variation, interrelation and relative importance of the grain yield determining components, grain number per square meter (GNO) and single grain weight (SGW). In addition to evaluating differences among cereal crops in yield determination, changes among different age groups (AG) were compared. Field experiments were carried out in 1970–2001 at 25 locations in Finland. Grain yield was recorded (at 15% moisture) and SGW (mg) and GNO (number m−2) determined. Frequencies of different GNO and SGW combinations were analysed for all crops and component means in different yield groups as well as among four AGs. In most cases GNO dominated SGW, representing the major yield component determining grain yield. GNO was highly responsive to favourable growth conditions. The change in GNO was especially high when recurrent, relatively low yield groups were compared, while at higher yields the role of SGW became increasingly important, but did not exceed that of GNO. The degree of GNO domination varied according to crop. Increased grain yield in spring oat and winter rye was associated with higher numbers of set grain, while spring barley and winter wheat responded to yield favouring conditions also through higher SGW. Despite GNO dominated SGW due to its responsiveness to growing conditions, its role in yield improvement was not obvious when the entries (n ≥ 30) were classified into four AGs. Improvements in grain yield derived from AG were associated with crop-specific GNO and/or SGW changes. 相似文献
24.
E. Costes P. E. Lauri S. Simon B. Andrieu 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(3):455-470
Plant architectural traits have been reported to impact pest and disease, i.e., attackers, incidence on several crops and to potentially provide alternative, although partial, solutions to limit chemical applications. In this paper, we introduce the major concepts of plant architecture analysis that can be used for investigating plant interactions with attacker development. We briefly review how primary growth, branching and reiteration allow the plant to develop its 3D structure which properties may allow it (or not) to escape or survive to attacks. Different scales are considered: (i) the organs, in which nature, shape and position may influence pest and pathogen attack and development; (ii) the individual plant form, especially the spatial distribution of leaves in space which determines the within-plant micro-climate and the shoot distribution, topological connections which influence the within-plant propagation of attackers; and (iii) the plant population, in which density and spatial arrangement affect the micro-climate gradients within the canopy and may lead to different risks of propagation from plant to plant. At the individual scale, we show how growth, branching and flowering traits combine to confer to every plant species an intrinsic architectural model. However, these traits vary quantitatively between genotypes within the species. In addition, we analyze how they can be modulated throughout plant ontogeny and by environmental conditions, here considered lato sensu, i.e. including climatic conditions and manipulations by humans. Examples from different plant species with various architectural types, in particular for wheat and apple, are provided to draw a comprehensive view of possible plant protection strategies which could benefit from plant architectural traits, their genetic variability as well as their plasticity to environmental conditions and agronomic manipulations. Associations between species and/or genotypes having different susceptibility and form could also open new solutions to improve the tolerance to pest and disease at whole population scale. 相似文献
25.
H Mameri I Bouchez C Pecquet N Raison-Peyron D Choudat H Chabane S Kerre S Denery-Papini Y Gohon P Briozzo M Laurière J Snégaroff 《Journal of agricultural and food chemistry》2012,60(32):8059-8068
Among the wheat prolamins, D-type glutenins display a highly repetitive sequence similar to ω-gliadins, but they contain a cysteine, that allows them to be included in the gluten macropolymers. An ω-gliadin-like D-type glutenin, an α-gliadin, and an ω5-gliadin-like D-type glutenin were obtained as recombinant proteins and compared using synchrotron radiation circular dichroism. This technique evidenced the strong thermostability of the ω5-gliadin-like protein. The IgE reactivity of recombinant proteins was evaluated using 45 sera from wheat-allergic patients. The sera from patients diagnosed with cutaneous hypersensitivity to hydrolyzed wheat proteins often reacted with the ω-gliadin-like D-type glutenin and α-gliadin, whereas the IgE reaction was less frequent after dietary sensitization. So, these two proteins could be useful to diagnose these diseases. The sera from patients with exercise-induced anaphylaxis recognized the ω5-gliadin-like protein as a positive control and, less frequently, the other proteins tested. Only some sera from patients with baker's asthma reacted with the proteins tested. 相似文献
26.
Long days partially depress tiller growth of spring cereals. In this study we characterised and quantified growing conditions and cultivar-induced variation in tiller traits and contribution of tillers to grain yield. Experiments were done at two locations in southern Finland, incorporating two nitrogen fertiliser application rates (80 and 120 kg N ha−1) and 12 two-row barley (Hordeum vulgare L.), 10 six-row barley, ten oat (Avena sativa L.) and 11 wheat (Triticum aestivum L.) cultivars. Spring cereal species differed significantly in their tillering: two-row barley was superior compared with other spring cereals, with the highest number and growth capacity of tillers and head-bearing tillers. Grain yield produced by tillers was, however, always modest compared with that of main shoots, ranging from 13% and 15% in oat and wheat to 20% in six-row barley and 64% in two-row barley. Cultivar and growing condition-induced differences were marked in tiller traits, but tillers were never able to out-yield the main shoot. This is likely to be emphasised by standard use of high seeding rates. Tillers are dominated by the main shoot under long day conditions at high latitudes, and tiller yield potential remains clearly underutilised even under conditions favouring growth. 相似文献
27.
Do Eurasian minnows (Phoxinus phoxinus L.) inhabiting brackish water enter fresh water to reproduce: Evidence from a study on otolith microchemistry 下载免费PDF全文
Roland Svirgsden Mehis Rohtla Anu Albert Imre Taal Lauri Saks Aare Verliin Markus Vetemaa 《Ecology of Freshwater Fish》2018,27(1):89-97
Dynamics of coastal fish assemblages in the Baltic Sea are still rather poorly understood. In particular, little information is available on migrations and movements of the small‐bodied littoral fish species like Eurasian minnow (Phoxinus phoxinus L.). Minnow is considered typically as a river and lake species, but it also inhabits brackish coastal waters of the Baltic Sea. In this study, we investigated movement patterns of brackish water inhabiting minnows using otolith microchemistry. Fish were collected from four different sites (from two bays and two stream mouths) around Saaremaa Island. The results indicated that at least three distinct migration patterns exist: (i) seawater residency, (ii) fast springtime migrations to fresh water or to bays with lower salinities (areas near stream mouths) and (iii) prolonged migrations to fresh water (some cases overwintering in streams). Migration patterns listed above were not evenly distributed among sites, and some individuals did not migrate to fresh water in every year. None of the analysed fish were freshwater residents. Additionally, potentially ontogenetic effects on Mn and Sr concentrations were observed in the otolith core regions, which may have important implications for the interpretation of otolith chemistry data. The overall findings of this study demonstrate that much more complex migration patterns exists in brackish water inhabiting minnow populations than previously thought and at least some individuals do enter freshwater to reproduce. 相似文献
28.
Lauri Rautkari Milena Properzi Frédéric Pichelin Mark Hughes 《Wood Science and Technology》2010,44(4):679-691
The chemistry and wetting behaviour of surface densified wood were investigated using FT-IR spectroscopy and contact angle
analyses. Furthermore, set-recovery of the surface under conditions of fluctuating humidity was measured and quantitative
microscopy analyses were undertaken. FT-IR indicated that no significant chemical changes took place during the densification
process. However, the wettability of the densified surfaces was significantly lower than unmodified surfaces. Following several
high humidity-oven dry cycles, it was found that this densification process was almost completely reversible, i.e., there
was full set-recovery. 相似文献
29.
Djers Göran Hadengganan Sakti Kuusipalo Jussi Otsamo Antti Vesa Lauri 《New Forests》1998,16(3):185-197
Seedling production from wildlings and early field performance of planted wildlings of four ecologically and commercially important Shorea species were studied in rainforest conditions of South Kalimantan (Indonesian Borneo). We report results from eight trials on Shorea johorensis, S. leprosula, S. faguetiana and S. parvifolia. Five trials were conducted in the nursery and three in the field. Growth medium, container type, wildling size or duration of shading period did not have significant effects on survival or growth of wildlings in the nursery. Keeping the potted wildlings in the greenhouse resulted in significantly higher survival than keeping them under shading net. Duration of greenhouse period had a significant effect on the survival of wildlings, with three weeks being the minimum period resulting in acceptable survival. Early field performance of hardened wildlings was better than that of seedlings raised from seed. Wildlings of 10–40 cm can be grown successfully in the nursery in several growth media and container types. A greenhouse period of 3–5 weeks is necessary for rooting and high survival. Use of wildlings is recommended as a supplementary method for producing dipterocarp planting stock. The techniques tested in the study are simple and appropriate for seedling production in conditions where skilled labor and advanced technology are not available. 相似文献
30.
Transfer of the Kosena Rfk1 gene,required in hybrid seed production,from oilseed rape to turnip rape
Radiant frost is a major abiotic stress, and one of the principal limiting factors for agricultural production worldwide,
including Australia. Legumes, including field pea, faba bean, lentil and chickpea, are very sensitive to chilling and freezing
temperatures, particularly at the flowering, early pod formation and seed filling stages. Radiant frost events occur when
plants and soil absorb the sunlight during the day time and radiate heat during the night when the sky is clear and the air
is still. Dense chilled air settles into the lowest areas of the canopy, where the most serious frost damage occurs. The cold
air causes nucleation of the intracellular fluid in plant tissues and the subsequent rupturing of the plasma membrane. Among
the cool season grain legume crops, chickpea, lentil and faba bean and field pea are the most susceptible to radiant frost
injury during the reproductive stages. The more sensitive stages are flowering and podding. Frost at the reproductive stage
results in flower abortion, poor pod set and impaired pod filling, leading to a drastic reduction in yield and quality. In
contrast, in the UK and European countries, frost stress is related to the vegetative stages and, in particular, the effects
of frost have been studied on cotyledon, uni/tri-foliolate leaf and seedling stages during the first few weeks of growth.
Few winter genotypes have been identified as frost tolerant at vegetative stages. Vegetative frost tolerance is not related
to reproductive frost tolerance, and hybrids from the vegetative frost-tolerant genotypes may not necessarily be tolerant
at the reproductive stage. Tolerance to radiant frost has an inverse relationship with plant age. In the field, frost tolerance
decreases from the vegetative stage to reproductive stage. Unlike wheat and barley, it is difficult to analyse and score frost
damage in grain legume crops due to the presence of various phenophases on one plant at the reproductive stage. The extent
of frost damage depends on the specific phenophases on a particular plant. However, current studies on genetic transformation
of cold tolerant gene(s), membrane modifications, anti-freeze substances and ice nucleating or inhibiting agents provide useful
information to improve our current understanding on frost damage and related mechanisms. The effects of frost damage on yield
and grain quality illustrate the significance of this area of research. This review discusses the problem of radiant frost
damage to cool season legumes in Australia and the associated research that has been carried out to combat this problem locally
and worldwide. The available literature varies between species, specific climatic conditions and origin. 相似文献