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81.
Andreu Colom-Cadena Roser Velarde Jesús Salinas Carmen Borge Ignacio García-Bocanegra Emmanuel Serrano Diana Gassó Ester Bach Encarna Casas-Díaz Jorge R López-Olvera Santiago Lavín Luís León-Vizcaíno Gregorio Mentaberre 《Acta veterinaria Scandinavica》2014,56(1)
Background
In 2010, an Iberian ibex (Capra pyrenaica hispanica) stock reservoir was established for conservation purposes in north-eastern Spain. Eighteen ibexes were captured in the wild and housed in a 17 hectare enclosure. Once in captivity, a caseous lymphadenitis (CLA) outbreak occurred and ibex handlings were carried out at six-month intervals between 2010 and 2013 to perform health examinations and sampling. Treatment with a bacterin-based autovaccine and penicillin G benzatine was added during the third and subsequent handlings, when infection by Corynebacterium pseudotuberculosis was confirmed. Changes in lesion score, serum anti-C. pseudotuberculosis antibodies and haematological parameters were analyzed to assess captivity effects, disease emergence and treatment efficacy. Serum acute phase proteins (APP) Haptoglobin (Hp), Amyloid A (SAA) and Acid Soluble Glycoprotein (ASG) concentrations were also determined to evaluate their usefulness as indicators of clinical status.Once in captivity, 12 out of 14 ibexes (85.7%) seroconverted, preceding the emergence of clinical signs; moreover, TP, WBC, eosinophil and platelet cell counts increased while monocyte and basophil cell counts decreased. After treatment, casualties and fistulas disappeared and both packed cell volume (PCV) and haemoglobin concentration significantly increased. Hp, SAA and ASG values were under the limit of detection or showed no significant differences.Conclusions
A role for captivity in contagion rate is suggested by the increase in antibody levels against C. pseudotuberculosis and the emergence of clinical signs. Although boosted by captivity, this is the first report of an outbreak of caseous lymphadenitis displaying high morbidity and mortality in wild ungulates. Treatment consisting of both vaccination and antibiotic therapy seemed to prevent mortality and alleviate disease severity, but was not reflected in the humoural response. Haematology and APP were not useful indicators in our study, perhaps due to the sampling frequency. Presumably endemic and irrelevant in the wild, this common disease of domestic small ruminants is complicating conservation efforts for the Iberian ibex in north-eastern Spain. 相似文献82.
83.
U1-specific protein C needed for efficient complex formation of U1 snRNP with a 5' splice site 总被引:18,自引:0,他引:18
One of the functions of U1 small nuclear ribonucleoprotein (snRNP) in the splicing reaction of pre-mRNA molecules is the recognition of the 5' splice site. U1 snRNP proteins as well as base-pair interactions between U1 snRNA and the 5' splice site are important for the formation of the snRNP-pre-mRNA complex. To determine which proteins are needed for complex formation, the ability of U1 snRNPs gradually depleted of the U1-specific proteins C, A, and 70k to bind to an RNA molecule containing a 5' splice site sequence was studied in a nitrocellulose filter binding assay. The most significant effect was always observed when protein C was removed, either alone or together with other U1-specific proteins; the binding was reduced by 50 to 60%. Complementation of protein C-deficient U1 snRNPs with purified C protein restored their 5' splice site binding activity. These data suggest that protein C may potentiate the base-pair interaction between U1 RNA and the 5' splice site. 相似文献
84.
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86.
Theory predicts that local mate competition (LMC) favors the evolution of female-biased sex ratios. Empirical support of this prediction is indirect and comes from comparative studies or from studies showing that individuals can adjust their offspring sex ratio in response to varying LMC intensities. Replicate lines from a population of the spider mite Tetranychus urticae were selected under three LMC intensities for up to 54 generations. Within each selection regime, the final sex ratio matched theoretical predictions. Furthermore, the ability of individuals to adjust their offspring sex ratio diminished in females evolving under strict LMC, but not in females evolving under relaxed LMC levels. These results provide direct experimental evidence for the evolutionary process by which LMC modifies sex-allocation strategies and suggest that evolution under strict and constant LMC may lead to a loss of phenotypic plasticity. 相似文献
87.
Chloral hydrate: a solvent for biological membranes 总被引:1,自引:0,他引:1
A buffer system conitainin chloral hydrate, taurine, and bromopyridinium lactate was used to dissolve several biological membranes and separate their protein components by polyacrylamide gel electrophoresis. This solvent system was capable of separating molecules of similar size on the hasis of their charge and allows easy recovery of the proteins Thus. aqueous chloral hydrate is an effective solvent for biological membranes. 相似文献
88.
Specificity of allogeneic cell recognition by human lymphocytes in vitro 总被引:14,自引:0,他引:14
Human lymphocytes proliferate in vitro in response to foreign histocompatibility antigens that are present on allogeneic lymphocytes. Within a population of immunocompetent lymphocytes there are specific subpopulations that respond to allogeneic cells from different individuals. A means of selectively eliminating such subpopulations is suggested. 相似文献
89.
Audun Korsaeth Philip Müller-Berghfer Konrad Mollenhauer Peter Fischer Martin Bach Hans-Georg Frede 《植物养料与土壤学杂志》1997,160(4):519-523
On the Effect of Organic Surface Cover on Lateral Transport of Isoproturon on Soil Surface The losses of the herbicide isoproturon with the surface runoff and the sediment loss have been measured by means of rainfall simulations on microplots (0.5 × 1 m2) with different mulch materials and increasing soil cover percentages (wheat straw vs. rape leafs). Soil cover by straw showed no significant effect on the runoff discharge, but the total loss of isoproturon increased between 22 and 37%. Soil cover by rape leafs diminished the runoff by between 13 and 61%, the reduction of isoproturon loss was in the same range. It was shown, that the different influences of different mulch materials on runoff and soil loss can lead to different pesticide losses. Therefore, the only giving of “mulch” without specification does not describe such experiments sufficiently. 相似文献
90.