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101.
Blikslager AT Yin C Cochran AM Wooten JG Pettigrew A Belknap JK 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(5):1191-1196
BACKGROUND: Recent reports indicate increased amounts of mRNA from inflammation-related genes in the prodromal stage of laminitis. HYPOTHESIS: Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) undergo distinct patterns of expression in equine laminae in the developmental stage (DEV) and acute clinical stage (LAM) of laminitis. ANIMALS: Horses selected from an outbred population were placed into 1 of 4 groups: DEV (n = 5), CON-3h (control group for DEV, n = 5), LAM (n = 5) and CON-10h (control group for LAM, n = 5). METHODS: Laminar and skin samples were obtained from (1) animals either undergoing leukopenia (DEV) or the onset of clinical signs of laminitis (LAM) after black walnut extract (BWE) administration and (2) animals either 3 (CON-3h) or 10 (CON-10h) hours after administration of water. Real-time quantitative polymerase chain reaction (RT-qPCR), immunoblotting, and immunohistochemical analysis were performed for COX-1 and COX-2. RESULTS: Upon immunohistochemical analysis of all 4 groups, COX-2 was expressed by most viable epithelial cells in both laminae and skin. COX-1 exhibited similar epithelial expression to COX-2 in skin epidermis, but was expressed exclusively in the basal layer of laminar epidermis. COX-1 protein was not detectable in dermal vasculature of equine skin or laminae, whereas COX-2 was present in endothelial and vascular smooth muscle cells of dermal vasculature in both skin and laminae in all groups. A marked increase in laminar COX-2 protein concentrations was detected on immunoblotting in the DEV group, although a lesser increase was observed in the LAM group. CONCLUSIONS AND CLINICAL IMPORTANCE: COX-2 protein expression is markedly increased in the resident laminar cell types in the developmental stage of BWE-induced laminitis. 相似文献
102.
Stijn Schauvliege Anna Binetti Luc Duchateau Jacoba Johanna van Dijk Frank Gasthuys 《Veterinary anaesthesia and analgesia》2018,45(5):648-657
Objective
To evaluate the cardiorespiratory effects of a 7° reverse Trendelenburg position (RTP) in anaesthetized horses.Study design
Randomized, non-blinded clinical trial.Animals
A total of 125 horses undergoing elective surgery in dorsal recumbency.Methods
Horses were allocated to one of three weight classes and assigned to be positioned either on a horizontal table or on a table in 7° RTP, according to a randomized block design. In all horses, anaesthesia was maintained with isoflurane in oxygen and a constant rate infusion of romifidine. All horses were mechanically ventilated throughout anaesthesia, and routine cardiovascular monitoring and arterial blood gas analysis were performed at 15-minute intervals and relevant variables calculated. Data from the first 60 minutes of anaesthesia were compared between both positions using a mixed model analysis of variance.Results
A significant interaction was found between position and weight class for the alveolar to arterial oxygen tension gradient and F-shunt: these variables were lower in RTP than in horizontal position in the two lowest weight classes and vice versa in the highest weight class. Arterial oxygen tension and oxygenation indices were significantly worse in the horses in the higher weight classes.Conclusions and clinical relevance
A 7° RTP did not result in clinically relevant changes in gas exchange or cardiovascular function. Horses with a higher body weight are at increased risk for hypoxaemia during anaesthesia in dorsal recumbency. 相似文献103.
Agnieszka PLACEK Bal Ram SINGH Anna GROBELAK Dariusz WKA sgeir R. ALMS Ma lgorzata KACPRZAK 《土壤圈》2018,28(3):555-560
正Dear Editor,Pinus sylvestris L.is one of the most popular and predominant tree species in Central Europe and Scandinavia.Its cultivation depends on atmospheric conditions,soil fertility,use of fertilizers,and individual characteristics of the trees.Pinus sylvestris L.wood,roots,and needles are used for energy production.Pi- 相似文献
104.
Nilsson Anna L. K. Skaugen Thomas Reitan Trond L’Abée-Lund Jan Henning Gamelon Marlène Jerstad Kurt Røstad Ole Wiggo Slagsvold Tore Stenseth Nils C. Vøllestad L. Asbjørn Walseng Bjørn 《BMC ecology》2020,20(1):1-12
While nitrogen and carbon stable isotope values can reflect ecological segregation, prey choice and spatial distribution in seabirds, the interpretation of bulk stable isotope values is frequently hampered by a lack of isotopic baseline data. In this study, we used compound-specific isotope analyses of amino acids (CSIA-AA) to overcome this constraint and to study interspecific differences, seasonal and historical changes in trophic positions of five seabird species, three penguins and two petrels, from a sub-Antarctic seabird community. CSIA-AA allowed comparing trophic positions of seabirds with temperate and polar distributions. Gentoo and Magellanic penguins had the highest trophic positions during the breeding season (3.7 and 3.9), but decreased these (2.9 and 3.3) during the feed-up for moult. Intra-specific differences were also detected in Thin-billed prions, where carbon isotope values clearly separated individuals with polar and temperate distributions, both in the breeding and interbreeding periods. Thin-billed prions that foraged in polar waters had lower trophic positions (3.2) than conspecifics foraging in temperate waters (3.8). We further investigated historical changes by comparing museum samples with samples collected recently. Our pilot study suggests that Rockhopper penguins, Magellanic penguins and Thin-billed prions with temperate non-breeding distributions had retained their trophic levels over a 90–100 year period, while Gentoo penguins and Thin-billed prions with polar non-breeding distributions had decreased trophic levels compared to historical samples. In contrast, Wilson’s storm-petrels had slightly increased trophic levels compared to samples taken in 1924–1930. We applied compound-specific stable isotope analyses across a range of contexts, from intra-specific comparisons between stages of the breeding cycle to inter-specific seabird community analysis that would not have been possible using bulk stable isotope analyses alone due to differences in isotopic baselines. 相似文献
105.
Fulvio Bordin Chiara Dalvit Mauro Caldon Laura Zulian Rosa Colamonico Simone Trincanato Barbara Mock Stefano Reale Franco Mutinelli Anna Granato 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(4):395-406
Scrapie is an ovine transmissible spongiform encephalopathy, and its susceptibility is associated with polymorphisms in the prion protein gene (PRNP). Genetic selection is currently the most effective mean for eradication of the susceptible VRQ allele in favour of resistant ARR allele. Maintenance of genetic diversity should be one of the major objectives in breeding programmes, especially in endangered breeds, and genetic information are an excellent alternative to pedigree data where these information are missing. The aim of our study was to determine changes of genetic variability in six native sheep breeds from autonomous province of Bolzano, northern Italy, following simulation of scrapie selection scenarios. A total of 684 rams were investigated for PRNP polymorphisms and for 10 microsatellite loci to estimate genetic variability. Across all loci, a total of 163 alleles were detected with a mean of 10.4 alleles per locus. Average observed (Ho) and unbiased expected (uHe) heterozygosity overall loci were 0.74 and 0.78, respectively, showing a statistically significant deviation from Hardy–Weinberg equilibrium (HWE) in all breeds. This heterozygosity deficit was confirmed by a positive fixation index (Fis), determining a moderate inbreeding in each breed. Simulating a soft selection, where only rams having at least a VRQ allele should be excluded from reproduction, Ho, uHe and Fis values remained almost unchanged, indicating that genetic variability should not be affected by the removal of these individuals. With a mild selection scenario, considering only rams with at least one ARR allele, we observed a decrease in the mean alleles per breed (8.9) and the maintenance of heterozygosity deficiency, except for two breeds, where it was any longer significant. These results showed that selection strategies allowing use of heterozygous as well homozygous ARR rams might be the right compromise to improve resistance to scrapie and to do not dramatically affect genetic variability of these breeds. 相似文献
106.
Maria Holmberg Anu Akujärvi Saku Anttila Lauri Arvola Irina Bergström Kristin Böttcher Xiaoming Feng Martin Forsius Inese Huttunen Markus Huttunen Yki Laine Heikki Lehtonen Jari Liski Laura Mononen Katri Rankinen Anna Repo Vanamo Piirainen Pekka Vanhala Petteri Vihervaara 《Landscape Ecology》2015,30(3):561-577
107.
108.
Anna Pretova Norbert C.A. de Ruijter André A.M. van Lammeren Jan H.N. Schel 《Euphytica》1992,65(1):61-69
Summary The capacity of the maize genotype 4c1 to regenerate microcalli and embryos from cultured microspores has been examined by comparing various cold pretreatments and culture media, using microspores and pollen at different stages of development. Viability of cultured cells was tested with FDA and their development was traced with light and fluorescence microscopy using DAPI as a nuclear dye.It was found that a pre-incubation of dissected flowers floating in a liquid nutrient medium at 8°C during 10–14 days was most successful for the induction of cell division. Among the developmental stages tested only the microspores appeared to regenerate. Subculture at 25°C in the same liquid medium, supplemented with 0.1 mg/l TIBA, gave highest rates of microspore division, i.e. up to 70% at 4 to 6 days of culture.All pathways described earlier for maize androgenic embryogenesis were observed within the 4c1 genotype. Symmetric divisions occurred in cultured microspores but most frequently asymmetric divisions lead to the formation of microcalli within 12 days of culture. In at least 60% of all dividing microspores cells were derived from the generative nucleus. Microcalli further developed either into loose or compact calli. Compact calli formed embryo-like structures.Abbreviations DAPI
4,6-diamidino-2-phenylindole
- Dicamba
3,6-dichloro-2-methoxy benzoic acid
- 2,4D
2,4 dichlorophenoxyacetic acid
- FDA
fluorescein diacetate
- PAA
phenylacetic acid
- TIBA
2,3,5-triiodobenzoic acid
- YP medium
Yu-Pei basal salt medium 相似文献
109.
Julia Cartelle Anna Pedr Roxana Savin Gustavo A. Slafer 《European Journal of Agronomy》2006,25(4):365-371
Average grain weight is a major yield component contributing to its variation, especially in Mediterranean regions where grain weight is frequently exposed to terminal stresses affecting grain growth. Most of the literature agrees that wheat grain growth is hardly limited by the source. However, no source–sink ratios studies seem to have been conducted in the Mediterranean region to determine to what degree wheat grain growth is actually limited by the source in these particular regions. We conducted two field experiments in Catalonia (north-eastern Spain), where an old cultivar (Anza) and a more recently released one (Soissons) were sown in a range of different nitrogen and water availabilities and sowing dates. This was to analyse the degree of source limitation for grain growth. Sink size was modified by removing half of the spikelets c. 10 days after anthesis, virtually doubling the availability of assimilates per grain effectively growing.
Trimming the spikes did not produce significant changes in grain growth rate or duration of grain filling. Consequently, grain weight did not respond noticeably to the reduction in sink demand and any eventual response has been far from representing a strong competition among grains during grain filling. 相似文献
110.
Book reviewed in this articles: Cereal Grain Protein Improvement. Shivanna, K. R., and B. M. Johri, The Angiosperm Pollen. Structure and Function. Gustafson, J. P., Gene Manipulation in Plant Improvement. Backer, A. W., Manual of Quantitative Genetics. Fishbeck, G., W. Plarre und W. Schuster (Hrag.) , Hoffmann , W., A. Plarre : Lehrbush der Züchtung landwirtschaftlicher Kulturflanzen, Bd. 2, Spezieller Teil, 2. Auflage. Dodds, J. H. (editor and author), Plant Genetic Engineering. Fiechter, A. (managing editor), Advanced in Biochemical Engineering/Biotechnology. Vol. 31. Plant Cell Culture. 相似文献