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101.
Favrot C Steffan J Seewald W Hobi S Linek M Marignac G Olivry T Beco L Nett C Fontaine J Roosje P Bergvall K Belova S Koebrich S Pin D Kovalik M Meury S Wilhelm S 《Veterinary dermatology》2012,23(1):45-50, e11
Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD. 相似文献
102.
Using an infrared camera, we measured the leaf temperature across different canopy positions of a 23-m-tall deciduous forest tree (Fagus sylvatica L.) including typical sun and shade leaves as well as intermediate leaf forms, which differed significantly in specific leaf area (SLA). We calculated a temperature index (I(G)) and a crop water stress index (CWSI) using the surface temperatures of wet and dry reference leaves. Additional indices were computed using air temperature plus 5 °C (I(G)?+?5, CWSI?+?5) as dry references. The minimum temperature of the wet leaf and the maximum temperature of the dry leaf proved to be most suitable as reference values. We correlated the temperature indices with leaf area-related conductance to water vapor (g(L)) using porometry at the leaf level and using xylem sap flow at the branch level. At the leaf and at the branch level, I(G) and CWSI were equally well suited as proxies of g(L), whereas the relationships of I(G)?+?5 and CWSI?+?5 with g(L) were only weak or even insignificant. At the leaf level, the correlations of I(G) and CWSI with g(L) were significant in all parts of the crown. The slopes of g(L) vs. I(G) and CWSI did not differ significantly among the crown parts; this indicates that they were not influenced by SLA or irradiance. At the branch level, close correlations (r?>?0.8) were found between temperature indices and g(L) across the crown. These results demonstrate that satisfactory relationships between temperature indices and g(L) can be established in tall trees even in those canopy parts that are exposed to relatively low levels of irradiance and exhibit relatively low values of g(L). 相似文献
103.
Kautto AH Alenius S Mossing T Becher P Belák S Larska M 《Veterinary microbiology》2012,156(1-2):64-71
Herding semi-domesticated reindeer has economic and social value for Sami people in the northern territories of Fennoscandia. However, with the intensification of reindeer husbandry, interspecies transmission of pathogens between reindeer and domestic animals may become a problem, especially for countries such as Sweden, Norway, and Finland where pestivirus and alphaherpesvirus have been eradicated in domestic ruminants. This study, which included 1158 Swedish reindeer, showed relatively high prevalence of antibodies against bovine viral diarrhoea virus (BVDV) (32%) and bovine herpesvirus-1 (BoHV-1) (53%). Adult animals were more often seropositive for BVDV and BoHV-1 (50% and 78%, respectively) than were calves (18 and 11%, respectively). While the seroprevalence of alphaherpesvirus was similar in different herding districts, pestivirus seropositivity was highest in the South and diminished towards the North of the Swedish reindeer herding area. High correlation of the seropositivity against both pathogens at both individual and herd levels may indicate possible mutual synergetic effects and may be explained by the immunosuppressive nature of the viruses. While alphaherpesvirus seroprevalence was probably related to putative cervid herpesvirus 2 (CvHV-2), the pestivirus infecting reindeer remains undefined. The virus neutralisation test of reindeer sera using different pestivirus strains, revealed higher titres against Border disease virus strains like 137/4 (BDV-1) and Reindeer-1 (BDV-2) than against BVDV-1. However, the virus was not identified by real time RT-PCR in any of the samples (n=276) from seronegative reindeers. The study showed that pestivirus and alphaherpesvirus infections are endemic in the Swedish reindeer population. 相似文献
104.
Leaves, the distal section of the soil-plant-atmosphere continuum, exhibit the lowest water potentials in a plant. In contrast to angiosperm leaves, knowledge of the hydraulic architecture of conifer needles is scant. We investigated the hydraulic efficiency and safety of Pinus pinaster needles, comparing different techniques. The xylem hydraulic conductivity (k(s)) and embolism vulnerability (P(50)) of both needle and stem were measured using the cavitron technique. The conductance and vulnerability of whole needles were measured via rehydration kinetics, and Cryo-SEM and 3D X-ray microtomographic observations were used as reference tools to validate physical measurements. The needle xylem of P. pinaster had lower hydraulic efficiency (k(s)?=?2.0?×?10(-4) m(2) MPa(-1) s(-1)) and safety (P(50)?=?-?1.5 MPa) than stem xylem (k(s)?=?7.7?×?10(-4) m(2) MPa(-1) s(-1); P(50)?=?-?3.6 to?-?3.2 MPa). P(50) of whole needles (both extra-vascular and vascular pathways) was?-?0.5 MPa, suggesting that non-vascular tissues were more vulnerable than the xylem. During dehydration to?-?3.5 MPa, collapse and embolism in xylem tracheids, and gap formation in surrounding tissues were observed. However, a discrepancy in hydraulic and acoustic results appeared compared with visualizations, arguing for greater caution with these techniques when applied to needles. Our results indicate that the most distal parts of the water transport pathway are limiting for hydraulics of P. pinaster. Needle tissues exhibit a low hydraulic efficiency and low hydraulic safety, but may also act to buffer short-term water deficits, thus preventing xylem embolism. 相似文献
105.
Drought and frost resistance of trees: a comparison of four species at different sites and altitudes
Katline Charra-Vaskou Guillaume Charrier Rémi Wortemann Barbara Beikircher Hervé Cochard Thierry Ameglio Stefan Mayr 《Annals of Forest Science》2012,69(3):325-333
Context
Drought and frost resistances are key factors for the survival and distribution of tree species. 相似文献106.
Context
Rotation length is known to affect timber quality in many plantation species, but its effect on the properties of Sitka spruce (Picea sitchensis) structural timber has not been quantified. 相似文献107.
Sharifah N. Syed Jaafar Johanna Baron Susanne Siebenhandl‐Ehn Thomas Rosenau Stefan Böhmdorfer Heinrich Grausgruber 《Plant Breeding》2013,132(6):546-552
Due to their antioxidant activity, anthocyanins are of increasing interest for nutritionists, food scientists and plant breeders. Anthocyanins in wheat grains are expressed in either the pericarp or aleurone layer. Previous studies revealed that different anthocyanins are present in wheat varieties carrying genes for either the purple pericarp or the blue aleurone trait. Progeny from crosses between red‐, purple‐ and blue‐grained wheat varieties were selected over several cycles for grain colour by visual scoring. Bulked F5 grains were evaluated for their total anthocyanin content by UV‐VIS spectrophotometry and HPLC‐MS. The results demonstrate that it is possible to increase the anthocyanin content by the combination of the different genetic backgrounds for purple pericarp and blue aleurone, even though the majority of progeny were within the range of the purple‐ and blue‐grained check varieties. Visual scoring for grain colour is efficient, reliable and fast for selection in early breeding generations. Advanced breeding lines with high anthocyanin content can be identified by simple extraction methods and spectrophotometric measurements. 相似文献
108.
Sandra Wenger Stefan Hoby Fabia Wyss Chiara Adami Christian Wenker 《Veterinary anaesthesia and analgesia》2013,40(2):176-180
ObjectiveTo evaluate the effects of medetomidine, midazolam and ketamine (MMK) in captive gorillas after premedication with oral zuclopenthixol.Study designCase series.AnimalsSix gorillas, two males and four females, aged 9–52 years and weighing 63–155 kg.MethodsThe gorillas were given zuclopenthixol dihydrochloride 0.2 ± 0.05 mg kg?1 per os twice daily for 3 days for premedication. On the day of anaesthesia the dose of zuclopenthixol was increased to 0.27 mg kg?1 and given once early in the morning. Anaesthesia was induced with medetomidine 0.04 ± 0.004 mg kg?1, midazolam 0.048 ± 0.003 mg kg?1 and ketamine 4.9 ± 0.4 mg kg?1 intramuscularly (IM). Upon recumbency, the trachea was intubated and anaesthesia was maintained on 1–2% isoflurane in oxygen. Physiological parameters were monitored every 10 minutes and arterial blood gas analysis was performed once 30–50 minutes after initial darting. At the end of the procedure, 42–115 minutes after initial darting, immobilisation was antagonized with atipamezole 0.21 ± 0.03 mg kg?1 and sarmazenil 5 ± 0.4 μg kg?1 IM.ResultsRecumbency was reached within 10 minutes in five out of six animals. One animal required two additional darts before intubation was feasible. Heart rate ranged from 60 to 85 beats minute?1, respiratory rate from 17 to 46 breaths minute?1 and temperature from 36.9 to 38.3 °C. No spontaneous recoveries were observed and anaesthetic level was stable. Blood gas analyses revealed mild respiratory acidosis, and mean PaO2 was 24.87 ± 17.16 kPa (187 ± 129 mmHg) with all values being above 13.4 kPa (101 mmHg). Recovery was smooth and gorillas were sitting within 25 minutes.Conclusion and clinical relevanceThe drug combination proved to be effective in anaesthetizing captive gorillas of various ages and both sexes, with minimal cardio-respiratory changes. 相似文献
109.
?Context
Tree species differ largely in their capability to produce characteristic shade leaves with effective morphological and physiological acclimation to low light.?Aims
By examining the sun/shade leaf differentiation in leaf morphology, foliar nitrogen and photosynthetic capacity in five temperate tree species of different successional status, we aimed at identifying those leaf traits that determine the development of a typical shade crown with low light-acclimated leaves.?Methods
Leaf morphology, foliar N content, photosynthetic capacity (V cmax, J max and A max) and leaf dark respiration (R d) were measured in the canopies of 26 adult trees of Fraxinus, Acer, Carpinus, Tilia and Fagus species.?Results
Six traits (the sun/shade leaf differentiation in specific leaf area, leaf size, A max per leaf area or per mass, photosynthetic N use efficiency and R d) were found to characterise best the degree of low light acclimation in shade leaves. All five species exhibited certain modifications in leaf morphology and/or physiology in response to low light; Fagus sylvatica showed the highest and Fraxinus excelsior the lowest shade leaf acclimation.?Conclusions
Our results indicate that the five early/mid- to late-successional species have developed species-specific low light acclimation strategies in their shade crowns which differ in terms of the relative importance of leaf morphological and physiological acclimation. 相似文献110.
Predicting western corn rootworm (Diabrotica virgifera virgifera LeConte; WCR) development in the field depends on models that use experimentally determined degree-days (°D). For constant temperature regimes, this temperature sum can be reliably used to predict hatch and development of WCR larvae. In the first experiment in climate cabinets, we evaluated the effects of varying day–night (4 and 6 °C difference) temperature regimes compared to equivalent constant temperature regimes on hatch, development, and recovery of WCR larvae from a non-diapausing population. Relative to constant diurnal temperatures, varying day–night temperatures resulted in earlier larval hatch and accelerated larval development (especially when day–night temperatures differed by 6 °C) due to direct temperature effects (i.e., the Kaufmann-effect) and to enhanced plant growth. For WCR eggs, the temperature sums needed for hatch in the field are overestimated when they are determined by models based on constant experimental temperatures. Recovery of larvae from soil was not affected by temperature, but was positively associated with plant height. In a second experiment we evaluated whether the found effect of varying temperature ranges on the acceleration of larval hatch is also influenced by the level of these varying temperatures. Initial hatch started earlier by varying diurnal temperatures only under a low-temperature regime (14 ± 4 °C). For herbivorous insects like WCR, plant growth effects induced by varying temperature regimes may result in increased variation in temperature-based developmental parameters. Consideration of these effects will improve models that predict WCR hatching patterns and will improve the development and timing of control strategies. 相似文献