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81.
82.
Little D Brown SA Campbell NB Moeser AJ Davis JL Blikslager AT 《American journal of veterinary research》2007,68(6):614-624
OBJECTIVE: To determine the effect of meloxicam and flunixin meglumine on recovery of ischemia-injured equine jejunum. ANIMALS: 18 horses. PROCEDURES: Horses received butorphanol tartrate; were treated IV with saline (0.9% NaCl) solution (SS; 12 mL; n = 6), flunixin meglumine (1.1 mg/kg; 6), or meloxicam (0.6 mg/kg; 6) 1 hour before ischemia was induced for 2 hours in a portion of jejunum; and were allowed to recover for 18 hours. Flunixin and SS treatments were repeated after 12 hours; all 3 treatments were administered immediately prior to euthanasia. Selected clinical variables, postoperative pain scores, and meloxicam pharmacokinetic data were evaluated. After euthanasia, assessment of epithelial barrier function, histologic evaluation, and western blot analysis of ischemia-injured and control jejunal mucosa samples from the 3 groups were performed. RESULTS: Meloxicam- or flunixin-treated horses had improved postoperative pain scores and clinical variables, compared with SS-treated horses. Recovery of transepithelial barrier function in ischemia-injured jejunum was inhibited by flunixin but permitted similarly by meloxicam and SS treatments. Eighteen hours after cessation of ischemia, numbers of neutrophils in ischemia-injured tissue were higher in horses treated with meloxicam or flunixin than SS. Plasma meloxicam concentrations were similar to those reported previously, but clearance was slower. Changes in expression of proteins associated with inflammatory responses to ischemic injury and with different drug treatments occurred, suggesting cyclooxygenase-independent effects. CONCLUSIONS AND CLINICAL RELEVANCE: Although further assessment is needed, these data have suggested that IV administration of meloxicam may be a useful alternative to flunixin meglumine for postoperative treatment of horses with colic. 相似文献
83.
84.
Pablo Aran Pablo Aguilar Thomas Bowen Matthew Farson Joseline Tapia Lara Vimercati John L. Darcy Adam J. Solon Dorota Porazinska Steven K. Schmidt Cristina Dorador 《水产资源保护:海洋与淡水生态系统》2021,31(8):2293-2299
- High elevation lakes are extreme ecosystems and serve as sentinels of various global changes.
- An expedition to Volcán Llullaillaco in 1996 discovered an unstudied high-elevation lake (6,170 m a.s.l.) that probably was formed as a result of the past eruptive events or climatic processes such as glacial retreat in the lake basin.
- This article describes an initial physical characterization of the lake and its microbial communities derived from two sampling expeditions in 2013 and 2016.
- The microbial community in the lake, with an area between 1.2 and 1.4 ha and a depth of 6.8 m, was dominated by Proteobacteria, Actinobacteria and Haloarchaea. In addition, 26 bacterial isolates were identified within the genera Subtercola, Xylophilus, Rhodanobacter, Mesorhizobium and Pseudomonas.
- Lago Llullaillaco is one of the highest recorded lakes in the world, and this study highlights the unique microbial diversity of this aquatic ecosystem and the importance of its preservation to understand the complex biological processes under polyextreme conditions.
85.
86.
Rubeena Shaikh Axel Diederichsen Myrtle Harrington Jennifer Adam Robert L. Conner Lone Buchwaldt 《Genetic Resources and Crop Evolution》2013,60(1):193-201
Anthracnose caused by the fungal pathogen Colletotrichum truncatum is a severe disease of lentil (Lens culinaris Medikus subsp. culinaris) causing premature defoliation and deep penetrating lesions on the stems leading to wilting and plant death. A total of 579 accessions from 20 countries were obtained from four germplasm collections in Russia, Poland, Bulgaria and Hungary. The accessions were collected between 1923 and 1988 and comprised mostly landraces. Consequently, many of the resistant entries contained susceptible plants which necessitated one or two cycles of selection of individual resistant plants for selfing and re-testing with the pathogen. Under controlled environmental conditions, plants of each accession were inoculated at early flower with C. truncatum race Ct0 (isolate 95A8) and race Ct1 (isolate 95B36), separately. Scoring of symptoms included number of lesions on the main stem, lesion penetration into the stem and amount of wilting. Resistance was obtained by single plant selection in 23 lentil accessions (4.0 %). Fifteen lines were generated with resistance to race Ct1 (2.6 %), seven with resistance to race Ct0 (1.2 %), and one line with resistance to both races. This is the first report on resistance in L. culinaris to C. truncatum race Ct0 as well as to the two races combined. Seed of homozygous resistant lines can be requested from the corresponding author, and are labeled with their original accession number with the prefix either -Ct0, -Ct1 or -Ct0Ct1 indicating resistance to one or both races of C. truncatum. 相似文献
87.
88.
Richard B. Primack Ins Ibez Hiroyoshi Higuchi Sang Don Lee Abraham J. Miller-Rushing Adam M. Wilson John A. Silander Jr. 《Biological conservation》2009,142(11):2569-2577
A comprehensive understanding of species phenological responses to global warming will require observations that are both long-term and spatially extensive. Here we present an analysis of the spring phenological response to climate variation of twelve taxa: six plants, three birds, a frog, and two insects. Phenology was monitored using standardized protocols at 176 meteorological stations in Japan and South Korea from 1953 to 2005, and in some cases even longer. We developed a hierarchical Bayesian model to examine the complex interactions of temperature, site effects, and latitude on phenology. Results show species-specific variation in the magnitude and even in the direction of their responses to increasing temperature, which also differ from site-to-site. At most sites the differences in phenology among species are forecast to become greater with warmer temperatures. Our results challenge the assertion that trends in one geographic region can be extrapolated to others, and emphasize the idiosyncratic nature of the species response to global warming. Field studies are needed to determine how these patterns of variation in species response to climate change affect species interactions and the ability to persist in a changing climate. 相似文献
89.
Background
Intake of colostrum after birth is essential to stimulate intestinal growth and function, and to provide systemic immunological protection via absorption of Immunoglobulin G (IgG). The birth order and weight of 745 piglets (from 75 litters) were recorded during a one-week period of farrowing. Only pigs weighing greater than 0.68 kg birth weight were chosen for the trial. Sow colostrum was collected during parturition, and piglets were bled between 48 and 72 hours post-birth. Piglet serum IgG and colostral IgG concentrations were determined by radial immunodiffusion.Results
Sow parity had a significant (P < 0.001) effect on sow colostral IgG concentration, being 5% higher in multiparous females. Sow colostral IgG concentration explained 6% and piglet birth order accounted for another 4% of the variation observed in piglet serum IgG concentration (P < 0.05); however, birth weight had no detectable effect. Piglet serum IgG concentration had both a linear (P < 0.05) and quadratic effect (P < 0.05) on % survival. Piglets with 1,000 mg/dl serum IgG or less (n=24) had a 67% survival; whereas, piglets with IgG concentrations between 2250 to 2500 mg/dl (n=247) had a 91% survival. Birth order had no detectable effect on survival, but birth weight had a positive linear effect (P < 0.05). Piglets weighing 0.9 kg (n = 107) at birth had a 68% survival rate, and those weighing 1.6 kg (n = 158) had an 89% survival.Conclusion
We found that the combination of sow colostrum IgG concentration and birth order can account for 10% of the variation of piglet serum IgG concentration and that piglets with less than 1,000 mg/dl IgG serum concentration and weight of 0.9 kg at birth had low survival rate when compared to their larger siblings. The effective management of colostrum uptake in neonatal piglets in the first 24 hrs post-birth may potentially improve survival from birth to weaning. 相似文献90.
Adam C.D. Barlow Md. Ishtiaq U. Ahmed Md. Mizanur Rahman 《Biological conservation》2008,141(8):2032-2040
Baseline data on distribution and abundance of tigers in the Sundarbans is required to identify problem areas and evaluate management strategies. This paper outlines a khal (creek) bank survey of track set frequency throughout the Bangladesh Sundarbans to aid formulation of a management-driven monitoring program. Three teams of two observers surveyed a total of 1 201 km of waterways throughout the Sundarbans, recording 1 338 tiger track sets. These sets became unrecognizable as tiger sign after a mean 10 days (range 6-14). Proportion of detectable sign recorded was 0.91. Mean (±standard error) sample unit track frequency was 1.12 ± 0.86 track sets/km of khal. The mean coefficient of variance in sample unit track rate, estimated by multiple counts of six sample units, was 0.21 (range 0.06-0.34). Track frequency generally increased from northeast to southwest. Four sample units (6%) had signs of reproduction, with a mean litter size of 1.75 ± 0.5. Monte Carlo simulation suggests a monitoring program of one complete survey every two years will have power of 0.8 (α = 0.2), to detect track frequency declines of ?19% and increases of ?17%. We recommend this monitoring scheme be implemented on the Indian side of the Sundarbans to provide a standard assessment of the tiger population and to form the basis for setting management objectives and evaluating transboundary conservation initiatives. 相似文献