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81.
David Cameron Duffy 《Biological conservation》1983,26(3):227-238
The roles of the El Niño phenomenon, a cessation of upwelling, and of human fishing in limiting populations of Peruvian guano birds (Guanay cormorant Phalacrocorax bougainvillii, Peruvian booby Sula variegata, and Peruvian brown pelican Pelecanus occidentalis thagus) were investigated using historical records and the scientific literature. In normal years, the combined populations of the three species showed an 18% increase per year. El Niños occurred at approximately five-year intervals and caused a population decrease of 17% and 35% desertion of nesting areas. In severe El Niños at approximately 12-year intervals, there was a mean decrease of 47% and complete nesting failure. El Niños varied in severity and a possible explanation is presented.In non-El Niño years, commercial fishing did not directly control bird populations through starvation of adults or drowning in nets. Increased commercial fishing apparently led to decreased nesting success: the greater the quantity of fish landed, the lower the percentage increase of the bird population that year.Short-lived, heavily-fished species such as anchoveta are in constant danger of population collapse during years of occasional, unpredictable reproductive failure. Bird populations could be maintained as buffers to prevent terminally-destructive overfishing by humans. 相似文献
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The asymmetric localization of messenger RNA (mRNA) and protein determinants plays an important role in the establishment of complex body plans. In Drosophila oocytes, the anterior localization of bicoid mRNA and the posterior localization of oskar mRNA are key events in establishing the anterior-posterior axis. Although the mechanisms that drive bicoid and oskar localization have been elusive, oocyte microtubules are known to be essential. Here we report that the plus end-directed microtubule motor kinesin I is required for the posterior localization of oskar mRNA and an associated protein, Staufen, but not for the anterior-posterior localization of other asymmetric factors. Thus, a complex containing oskar mRNA and Staufen may be transported along microtubules to the posterior pole by kinesin I. 相似文献
83.
Comparison between Urine Protein: Creatinine Ratios of Samples Obtained from Dogs in Home and Hospital Settings 下载免费PDF全文
M.E. Duffy A. Specht R.C. Hill 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(4):1029-1035
Background
The urine protein:creatinine ratio (UPC) is used to quantify urine protein excretion and guide recommendations for monitoring and treatment of proteinuria.Hypothesis/Objectives
Home urine samples will have lower UPCs than hospital samples. The objectives were to compare UPCs of samples collected in each setting and to determine whether environment of sample collection might affect staging, monitoring or treatment recommendations.Animals
Twenty‐four client‐owned dogs.Methods
Prospective, nonmasked study. Clients collected a urine sample from their dog at home and a second sample was collected at the hospital. Dogs receiving corticosteroids or angiotensin‐converting enzyme inhibitors were excluded, as were those with urine samples of inadequate volume, no protein on dipstick analysis, or active urine sediment. Samples were refrigerated after collection, dipstick and sediment evaluations were completed and each sample was frozen at −80°C within 12 hours. UPCs were performed on frozen samples within 2 months.Results
From 81 paired samples, 57 were excluded. Of the remaining 24, 12/24 (50%) had higher hospital sample UPCs, 9/24 (38%) had identical UPCs, and 3/24 (12%) had lower hospital UPCs. The UPCs of hospital samples were higher than home samples for the total population (P = .005) and the subset with UPC > 0.5 (P = .001).Conclusions
Setting and related circumstances of urine collection in dogs is associated with UPC differences; results are usually higher in hospital than in home samples. This difference has the potential to affect clinical interpretation. 相似文献84.
Occurrence,Antibiotic Resistance and Molecular Characterization of Listeria monocytogenes in the Beef Chain in the Republic of Ireland 下载免费PDF全文
B. K. Khen O. A. Lynch J. Carroll D. A. McDowell G. Duffy 《Zoonoses and public health》2015,62(1):11-17
This study investigated the occurrence, concentration and key characteristics of Listeria monocytogenes in beef chain samples (n = 1100) over a 2‐year period (July 2007–June 2009). Listeria monocytogenes was isolated from bovine hides (27%), pre‐chill carcasses (14%) and ground beef (29%), but not from ready‐to‐eat (RTE) beef. The concentration of the pathogen in the majority (95%) of contaminated samples was low and detected by enrichment only. The highest concentrations recovered (100–200 CFU/g) were in ground beef samples. The most commonly isolated serotype group was 1/2a (58%) followed by 4b (12%), 1/2b (10%) and 1/2c (6%). A small portion (<5%) isolates had demonstrated resistance to key anti‐microbials including ampicillin, vancomycin and gentamycin which are recommended treatment options for listeriosis. Pulsed‐field gel electrophoresis showed indistinguishable profiles for a number of isolates recovered from the hide and carcass (after slaughter and dressing) of the same animals, highlighting the role of hides as a source of contamination. Equally, indistinguishable pulsotypes for isolates recovered at different stages and time points (up to 6 months apart) in the beef chain demonstrated the persistence of specific clones in the factory, process and distribution environments. Overall, the study demonstrated a high prevalence of clinically significant L. monocytogenes entering and progressing along the beef chain and highlights the needs to control cross‐contamination during beef processing and distribution and the need for thorough cooking of raw beef products. 相似文献
85.
Roque JB O'Leary CA Kyaw-Tanner M Latter M Mason K Shipstone M Vogelnest L Duffy D 《Veterinary dermatology》2011,22(3):257-266
Human and canine atopic dermatitis (AD) share an association with IgE specific to environmental allergens, but few studies have evaluated serum allergen‐specific IgE in nonatopic dogs. This study compared serum allergen‐specific IgE levels in 30 atopic and 18 nonatopic West Highland white terriers. Atopic dermatitis was confirmed using standard criteria. Nonatopic dogs were over 5 years of age and had no clinical signs or history of AD. Serum allergen‐specific IgE levels were measured with Allercept® IgE ELISAs using a 48‐allergen Australian panel. Positive reactions were defined as ≥150 ELISA absorbance units. Intradermal tests were performed in 16 atopic dogs, either at the time of or at various times prior to serum collection. In atopic dogs, the most common positive ELISA and intradermal test results were to Dermatophagoides farinae (11 of 30 dogs), but there were no statistically significant correlations between results from the two methods for any allergen. In nonatopic dogs, multiple high‐positive ELISA reactions were reported to 45 of 48 allergens, most commonly D. farinae and Tyrophagus putrescentiae (17 of 18 dogs each). Positive ELISA results in nonatopic dogs were statistically significantly higher than those in atopic dogs for 44 of 48 allergens, including two allergens (D. farinae and Dermatophagoides pteronyssinus) commonly regarded as significant in canine AD. In conclusion, positive allergen‐specific IgE ELISAs were not specific for canine AD, and high allergen‐specific IgE levels were seen in nonatopic dogs. The clinical significance of this and whether it characterizes a protective phenotype is unclear. 相似文献
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