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981.
982.
Muellner P Marshall JC Spencer SE Noble AD Shadbolt T Collins-Emerson JM Midwinter AC Carter PE Pirie R Wilson DJ Campbell DM Stevenson MA French NP 《Preventive veterinary medicine》2011,102(3):242-253
Until recently New Zealand had one of the highest rates of human campylobacteriosis reported by industrialized countries. Since the introduction of a range of control measures in the poultry production chain a reduction in human cases of around 50% has been observed nationwide. To inform risk managers a combination of spatial, temporal and molecular tools - including minimum spanning trees, risk surfaces, rarefaction analysis and dynamic source attribution modelling - was used in this study to formally evaluate the reduction in disease risk that occurred after the implementation of control measures in the poultry industry. Utilizing data from a sentinel surveillance site in the Manawatu region of New Zealand, our analyses demonstrated a reduction in disease risk attributable to a reduction in the number of poultry-associated campylobacteriosis cases. Before the implementation of interventions poultry-associated cases were more prevalent in urban than rural areas, whereas for ruminant-associated cases the reverse was evident. In addition to the overall reduction in prevalence, this study also showed a stronger intervention effect in urban areas where poultry sources were more dominant. Overall a combination of molecular and spatial tools has provided evidence that the interventions aimed at reducing Campylobacter contamination of poultry were successful in reducing poultry-associated disease and this will inform the development of future control strategies. 相似文献
983.
A 4 yr old pregnant female shih tzu was presented with abdominal discomfort and bloody vulvar discharge. The nongravid uterine horn was reflected caudally over the trigone, obstructing urine outflow. A cesarian section and ovariohysterectomy were performed. Postoperatively, the hematuria and pollakiuria resolved. Seventeen days later, the pelvic urethra was completely obstructed by a soft tissue mass that was identified by rectal palpation, blocked catheterization attempts, contrast radiography, ultrasonography, and surgery. Management included temporary cystostomy tube and definitive prepubic urethrostomy. Histologic diagnosis was severe, multifocal, necrosuppurative urethritis with fibroplasia, fibrosis, and cellulitis, apparently secondary to ischemia. Delayed urethral obstruction is a potential complication of canine uterine torsion. 相似文献
984.
Heegaard PM Stockmarr A Piñeiro M Carpintero R Lampreave F Campbell FM Eckersall PD Toussaint MJ Gruys E Sorensen NS 《Veterinary research》2011,42(1):50
ABSTRACT: The acute phase protein (APP) response is an early systemic sign of disease, detected as substantial changes in APP serum concentrations and most disease states involving inflammatory reactions give rise to APP responses. To obtain a detailed picture of the general utility of porcine APPs to detect any disease with an inflammatory component seven porcine APPs were analysed in serum sampled at regular intervals in six different experimental challenge groups of pigs, including three bacterial (Actinobacillus pleuropneumoniae, Streptococcus suis, Mycoplasma hyosynoviae), one parasitic (Toxoplasma gondii) and one viral (porcine respiratory and reproductive syndrome virus) infection and one aseptic inflammation. Immunochemical analyses of seven APPs, four positive (C-reactive protein (CRP), haptoglobin (Hp), pig major acute phase protein (pigMAP) and serum amyloid A (SAA)) and three negative (albumin, transthyretin, and apolipoprotein A1 (apoA1)) were performed in the more than 400 serum samples constituting the serum panel. This was followed by advanced statistical treatment of the data using a multi-step procedure which included defining cut-off values and calculating detection probabilities for single APPs and for APP combinations. Combinations of APPs allowed the detection of disease more sensitively than any individual APP and the best three-protein combinations were CRP, apoA1, pigMAP and CRP, apoA1, Hp, respectively, closely followed by the two-protein combinations CRP, pigMAP and apoA1, pigMAP, respectively. For the practical use of such combinations, methodology is described for establishing individual APP threshold values, above which, for any APP in the combination, ongoing infection/inflammation is indicated. 相似文献
985.
Cadot P Hensel P Bensignor E Hadjaje C Marignac G Beco L Fontaine J Jamet JF Georgescu G Campbell K Cannon A Osborn SC Messinger L Gogny-Goubert M Dubreuil P Moussy A Hermine O 《Veterinary dermatology》2011,22(6):554-564
This study investigated the efficacy and safety of masitinib, a selective tyrosine kinase inhibitor capable of downregulating mast cell functions, for treatment of canine atopic dermatitis (CAD). Dogs with confirmed CAD received masitinib at 12.5 mg/kg/day (n = 202) or control (n = 104) for 12 weeks. A reduction in CAD Extent and Severity Index (CADESI-02) score of ≥ 50% at week 12 was observed in 61% of masitinib-treated dogs versus 35% of control dogs (P < 0.001), according to the modified intent-to-treat population. For dogs resistant to ciclosporin and/or corticosteroids (60% of the study population), CADESI-02 response rates were 60 versus 31%, respectively (P = 0.004). The mean reduction in pruritus score of severely pruritic dogs was 46 versus 29%, respectively (P = 0.045). Furthermore, 65% of owners with severely pruritic dogs assessed masitinib efficacy as good/excellent versus 35% control (P = 0.05). Overall, 63% of investigators assessed masitinib efficacy as good/excellent versus 35% control (P < 0.001). Premature discontinuations from the modified intent-to-treat population (28.2% masitinib versus 26.0% control) were mainly due to adverse events (13.4 versus 4.8%, respectively) or lack of efficacy (12.4 versus 18.3%, respectively). In total, 13.2% dogs presented with severe adverse events (16.0% masitinib versus 7.7% control). Masitinib showed a risk of reversible protein loss, although regular surveillance of blood albumin and proteinuria allowed for discontinuation of treatment while the dog was still clinically asymptomatic. Masitinib proved to be an effective and mostly well-tolerated treatment of CAD, including severe and refractory cases, with medically manageable adverse effects. 相似文献
986.
The respiratory, acid-base, and ionoregulatory responses of juvenile rainbow trout (Salmo gairdneri) were monitored during exposure of the fish in the laboratory to inorganic Al (2.8 μM) over the pH range 4.0 to 6.5. Responses to Al were most severe at pH 6.1 and 4.5, mortality being primarily due to asphyxia at pH 6.1 and to electrolyte loss at pH 4.5. Competition between the H+-ion and Al for binding at the gill surface is offered as an explanation for the decreased toxicity of Al at pH 4.0, one which is compatible with the free-ion toxicity model that has been developed for other metals. The physiologically distinct response of S. gairdneri to Al at pH 6.1 is less amenable to unambiguous interpretation. If a mixed ligand hydroxo-Al complex is incorporated in the free-ion model, and if it is assumed that the two Al species, [Al-L-gill] and [HO-Al-L-gill], provoke distinct toxicological responses, then a bimodal toxicological response to Al is indeed predicted. An alternative explanation of the apparent toxic action of Al at pH 6.1, i.e., at pH values close to that of minimum Al solubility, is the precipitation of solid Al(OH)3 at the gill surface, i.e., a ‘physical’ effect rather than a biochemical one. 相似文献
987.
A relationship between atmospheric transmittance and the daily range of air temperature is developed. The relationship is Tt = A[1—exp(—BΔTc)] where Tt is the daily total atmospheric transmittance, ΔT is the daily range of air temperature, and A, B, and C are empirical coefficients, determined for a particular location from measured solar radiation data. Tests on three data sets indicate that 70–90% of the variation in daily solar radiation can be accounted for by this simple model. 相似文献
988.
989.
Interaction of a liver-specific nuclear factor with the fibrinogen and alpha 1-antitrypsin promoters 总被引:82,自引:0,他引:82
G Courtois J G Morgan L A Campbell G Fourel G R Crabtree 《Science (New York, N.Y.)》1987,238(4827):688-692
990.
Benschoter CA Allison TC Boyd JF Brooks MA Campbell JW Groves RO Heimpel AM Mills HE Ray SM Warren JW Wolf KE Wood EM Wrenn RT Zein-Eldin Z 《Science (New York, N.Y.)》1970,169(3944):470-472
Lunar material returned from the first manned landing on the moon was assayed for the presence of replicating agents possibly harmful to life on earth. Ten species of lower animals were exposed to lunar material for 28 days. No pathological effects attributable to contact with lunar material were detected. 相似文献