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1.
Randomized placebo-controlled crossover studies were carried out in dogs to evaluate how two non-steroidal anti-inflammatory drugs (NSAID) might modulate an acute post-traumatic inflammatory reaction. Two "identical" surgical interventions were performed on the forelimbs of each animal with an interval of 28 days, to enable a paired comparison of the inflammatory signs and the wound/bone healing processes. At one operation 8 dogs received 300 mg phenylbutazone twice daily for 8 days starting on the day before surgery, and at the other operation matching placebo tablets were given. In a similar placebo-controlled trial another group of 8 dogs received 5 mg indomethacin twice daily. With phenylbutazone the post-operative swelling was not significantly reduced compared to placebo, but there was less pain and limping. With indomethacin the swelling was somewhat reduced, but there was no consistent difference to placebo in the pain and limping assessments. None of the drugs appeared to distinctly effect the wound or fracture healing, as evaluated by clinical inspection, comparison of radiographs and comparison of bone sections from the sites of surgery. It proved difficult to select an appropriate dosage of indomethacin due to its high potential to induce GI ulceration and bleeding in dogs. In this experimental surgical model with an acute inflammation, neither phenylbutazone nor indomethacin showed impressive anti-inflammatory or analgesic properties. In the same model paracetamol has proved to significantly and more efficiently, reduce both swelling and pain without any noticeable adverse effects, and appears to be a better alternative than the two presently tested NSAID. 相似文献
2.
Brian Reavy Maria Sandgren Hugh Barker Pekka Heino Per Oxelfelt 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(9):829-834
Resistance tests were made on seedlings of transformed lines of Nicotiana benthamiana which contain a transgene encoding the coat protein (CP) gene of a Scottish isolate of potato mop-top virus (PMTV). This transgene has been reported to confer strong resistance to the PMTV isolate from which the transgene sequence was derived and also to a second Scottish isolate. Plants of lines of the transgenic N. benthamiana were as resistant to two Swedish and two Danish PMTV isolates as to a Scottish isolate, and of five lines tested, greater than 93.5% of transgenic plants were immune. The coat protein gene sequences of these four Scandinavian isolates were very similar to those of the two Scottish isolates. The greatest divergence between the isolates was three amino acid changes and there was less than 2% change in CP gene nucleotide sequence. It is concluded that the PMTV CP transgene used in these experiments could confer resistance against isolates from different geographical areas because it is becoming apparent that the CP genes of PMTV isolates are highly conserved. 相似文献
3.
Time-frequency and complexity analyses for differentiation of physiologic murmurs from heart murmurs caused by aortic stenosis in Boxers 总被引:1,自引:0,他引:1
Höglund K Ahlstrom CH Häggström J Ask PN Hult PH Kvart C 《American journal of veterinary research》2007,68(9):962-969
OBJECTIVE: To investigate whether time-frequency and complexity analyses of heart murmurs can be used to differentiate physiologic murmurs from murmurs caused by aortic stenosis (AS) in Boxers. ANIMALS: 27 Boxers with murmurs. PROCEDURES: Dogs were evaluated via auscultation and echocardiography. Analyses of time-frequency properties (TFPs; ie, maximal murmur frequency and duration of murmur frequency > 200 Hz) and correlation dimension (T(2)) of murmurs were performed on phonocardiographic sound data. Time-frequency property and T(2) analyses of low-intensity murmurs in 16 dogs without AS were performed at 7 weeks and 12 months of age. Additionally, TFP and T(2) analyses were performed on data obtained from 11 adult AS-affected dogs with murmurs. RESULTS: In dogs with low-intensity murmurs, TFP or T(2) values at 7 weeks and 12 months did not differ significantly. For differentiation of physiologic murmurs from murmurs caused by mild AS, duration of murmur frequency > 200 Hz was useful and the combination assessment of duration of frequency > 200 Hz and T(2) of the murmur had a sensitivity of 94% and a specificity of 82%. Maximal murmur frequency did not differentiate dogs with AS from those without AS. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that assessment of the duration of murmur frequency > 200 Hz can be used to distinguish physiologic heart murmurs from murmurs caused by mild AS in Boxers. Combination of this analysis with T(2) analysis may be a useful complementary method for diagnostic assessment of cardiovascular function in dogs. 相似文献
4.
Growth and carbon dynamics in mixed grass–red clover leys were simulated using a growth model for pure stands based on radiation use, allocation within plant and loss of biomass. The model and its parameter values were taken from previous applications of the model to pure swards of grass and red clover grown in the same experiment at the same sites and years. 相似文献
5.
Pigs deficient in vitamin E and selenium had a decreased contrast of the intracellular membranes compared with pigs supplemented with vitamin E and selenium. Other common changes in the deficient animals included a reduced number of microvilli, with a short and irregular appearance, numerous swollen mitochondria with empty spaces and intercellular oedema. It is suggested that these morphological changes are attributed to the insufficient supply of vitamin E and selenium, though it is not excluded that particular intestinal factors may participate in the development of the lesions. 相似文献
6.
Frauke Ecke Pernilla Christensen Per Sandström Birger Hörnfeldt 《Landscape Ecology》2006,21(4):485-497
Several studies indicate a long-term decline in numbers of different species of voles in northern Fennoscandia. In boreal Sweden, the long-term decline is most pronounced in the grey-sided vole (Clethrionomys rufocanus). Altered forest landscape structure has been suggested as a possible cause of the decline. However, habitat responses of grey-sided voles at the landscape scale have never been studied. We analyzed such responses of this species in lowland forests in Västerbotten, northern Sweden. Cumulated spring densities representing 22 local time series from 1980–1999 were obtained by a landscape sampling design and were related to the surrounding landscape structure of 2.5×2.5 km plots centred on each of the 22 1-ha trapping plots. In accordance with general knowledge on local habitat preferences of grey-sided voles, our study supported the importance of habitat variables such as boulder fields and old-growth pine forest at the landscape scale. Densities were negatively related to clear cuts. Habitat associations were primarily those of landscape structure related to habitat fragmentation, distance between habitat patches and patch interspersion rather than habitat patch type quantity. Local densities of the grey-sided vole were positively and exponentially correlated with spatial contiguity (measured with the fragmentation index) of old-growth pine forest, indicating critical forest fragmentation thresholds. Our results indicate that altered land use might be involved in the long-term decline of the grey-sided vole in managed forest areas of Fennoscandia. We propose two further approaches to reveal and test responses of this species to changes in landscape structure. 相似文献
7.
Seeds of Juniperus procera collected from five provenances across its geographic range in Ethiopia were subjected to cold-moist stratification at 5°C
or 10°C for 6–12 weeks. The effect of aqueous smoke solution in overcoming the light requirement for germination, and the
potential of visible (VIS) and near infrared reflectance (NIR) spectroscopy for sorting sound and insect-damaged seeds were
also investigated. Highly significant differences in germination were detected among provenances (P < 0.0001) and stratification periods (P < 0.0001), but not between temperature regimes (P=0.111). Seeds from the south and southeast distribution ranges had higher percentage germination after 6 weeks of stratification
than seeds collected from north, northwest and central ranges of distribution. The smoke treatment did not affect germination
regardless of whether the seeds were exposed to light. Exposure to light increased germination capacity three fold. Sound
and damaged seeds were distinguished with 90% accuracy using VIS + NIR spectroscopy. It can be concluded that dormancy in
juniper seeds varies with provenances, and cold stratification for 6 weeks alleviates dormancy in some seed lots. Tentatively,
smoke treatment seems ineffective in overcoming photo-dormancy in juniper seeds. VIS + NIR spectroscopy has demonstrated a
great potential for sorting damaged seeds, thereby upgrading seed lot purity. 相似文献
8.
The potential drivers in forming avian biodiversity hotspots in the East Himalaya Mountains of Southwest China 总被引:1,自引:0,他引:1 下载免费PDF全文
Little has been published to describe or interpret Asian biodiversity hotspots, including those in the East Himalayan Mountains of Southwest China (HMSC), thus making necessary a review of the current knowledge. The Pliocene and Pleistocene geological and glacial histories of the Asian continent differ from those of Europe and North America, suggesting different mechanisms of speciation and extinction, and, thus, different responses to climate changes during the Quaternary glaciations. This short review summarizes potential drivers in shaping and maintaining high species richness and endemism of birds in the HMSC. The geographical location at the junction of different biogeographical realms, the wide range of habitats and climates along the extensive elevational range, the complex topography and the distinct geological history of this region have probably contributed to the evolution of an exceptionally species‐rich and endemic‐rich, specialized montane avian fauna. The Mountain systems in the HMSC may have provided refugia where species survived during the glacial periods and barriers for preventing species dispersal after the glacial periods. More studies are required to further test this refugia hypothesis by comparing more cold‐tolerent and warm‐tolerent species. 相似文献
9.
A spawning and egg collecting system for fish with pelagic eggs is described and discussed. The spawning unit is a 175 m3 submersible plastic pen supported by a polyethylene floating collar. The eggs are collected by rotating the water column in the pen and placing a net in the rotating water. The system is inexpensive and easy to operate. Temperature and illumination control are feasible.The quantity collected in the 1981 spawning season was 138 million eggs. Obtained eggs were of good quality. The theoretical spawning potential of the brood stock was 271 million eggs. This difference was mainly ascribed to suboptimal collection, but also to incomplete spawning and sinking of unfertilized and dead eggs. 相似文献
10.
Neguvon (Bayer) was administered orally as a therapeutic against the parasitic copepod Lepeophtheirus salmonis. An effective dose is stated and the concentration remaining in fish muscle was measured. 相似文献