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991.
Judith D. Seltzer Alison K. Flynn‐Lurie Rosanna Marsella Meghan M. Brennan 《Veterinary dermatology》2010,21(3):249-258
Stannous fluoride (SF) is an antibacterial compound that has been successfully used to treat gingivitis in people and dogs, and cutaneous bacterial infections in horses. The purpose of this prospective, double‐blinded, placebo‐controlled clinical trial was to investigate the efficacy of 0.2% SF spray (BacDerm®; Emerald 3 Enterprises Inc., Camdenton, MO, USA) for the treatment of canine superficial pyoderma. Twenty‐six privately owned dogs with bacterial skin infections diagnosed on clinical signs, cytology and aerobic culture were enrolled. Dogs were randomly assigned to vehicle only or active ingredient treatment groups. The product was applied topically to affected areas once daily for 28 days, with assessments at days 0, 14, 28 and 42. Clinical and cytological evaluations were performed by the same investigators at each visit. Owners scored the improvement of hair coat, odour, pruritus and overall improvement at each recheck. Linear mixed models showed significant effects of treatment (P < 0.0001) and time (P = 0.0037) for investigator’s scores, and a significant time effect for owners’ haircoat (P = 0.0077) and odour (P = 0.0170) improvement scores. Dogs in both placebo and SF groups showed some improvement over time, and the investigator’s scores on days 0 and 28 were not significantly different between groups for both (t‐test P > 0.05). Spearman’s rho correlation coefficients revealed a significant negative correlation between investigator’s scores and all categories of owners’ assessment scores in dogs of both groups. Although some dogs improved on SF, this study does not support the use of 0.2% SF as sole therapy for canine superficial pyoderma. 相似文献
992.
Summerhayes GR Leavesley M Fairbairn A Mandui H Field J Ford A Fullagar R 《Science (New York, N.Y.)》2010,330(6000):78-81
After their emergence by 200,000 years before the present in Africa, modern humans colonized the globe, reaching Australia and New Guinea by 40,000 to 50,000 years ago. Understanding how humans lived and adapted to the range of environments in these areas has been difficult because well-preserved settlements are scarce. Data from the New Guinea Highlands (at an elevation of ~2000 meters) demonstrate the exploitation of the endemic nut Pandanus and yams in archaeological sites dated to 49,000 to 36,000 years ago, which are among the oldest human sites in this region. The sites also contain stone tools thought to be used to remove trees, which suggests that the early inhabitants cleared forest patches to promote the growth of useful plants. 相似文献
993.
Kai-Shu Ling D. Michael Jackson Howard Harrison Alvin M. Simmons Zvezdana Pesic-VanEsbroeck 《Crop Protection》2010
The incidence of Sweet potato leaf curl virus (SPLCV), a Begomovirus, on sweetpotato, Ipomoea batatas (L.) Lam. (Convolvulaceae), in South Carolina, U.S.A. has increased rapidly in recent years. This is likely due to the use of infected propagating materials and the increasing population of its vector, the sweetpotato whitefly, Bemisia tabaci (Gennadius). In this study, we demonstrated in field experiments that SPLCV infection reduced the yields of most heirloom sweetpotato lines relative to the yields of non-infected plants. Real-time polymerase chain reaction (PCR) technology specific to several common sweetpotato viruses was used to determine the virus infection status in 69 selected accessions of heirloom sweetpotato lines. Meristem tip culture technology was used to regenerate virus-free plants from these materials. To ensure the virus-free status, each mericlone was evaluated using real-time PCR and graft bio-indexing on the indicator species, Ipomoea setosa Ker Gawl. Mericlones of 27 cultivars were found to be free of the viruses. The 27 cultivars were included in a field test to determine the effect of SPLCV infection on yield. Yields of virus-free plants of the cultivars ranged from 10 to 80% greater than the yields of SPLCV-infected plants. However, the yield differences between virus-free and infected plants were diminished in the second year of the field experiment due to a rapid re-infection by SPLCV. These results demonstrate the importance of using certified, virus-tested seed roots or cuttings. The rapid re-infection of the virus-tested sweetpotato plants with SPLCV observed in these studies suggests that management of the whitefly population should be a critical element in control of this important virus. 相似文献
994.
Evaluation of Lameness Associated with Arthroscopy and Arthrotomy of the Normal Canine Cubital Joint
Loretta J. Bubenik DVM MS Spencer A. Johnson VMD DACVS Mark M. Smith VMD DACVS DAVDC Rick D. Howard DVM PhD DACVS Richard V. Broadstone DVM PhD DACVA 《Veterinary surgery : VS》2002,31(1):23-31
OBJECTIVE: To evaluate gait, range of motion (ROM), and lameness in normal dogs after arthroscopy or arthrotomy of the cubital joint. STUDY DESIGN: Experimental study. ANIMALS: Fourteen mature, healthy dogs. METHODS: Dogs were randomly assigned to treatment groups. Seven underwent arthrotomy and 7 underwent arthroscopy of the left cubital joint. Dogs were evaluated using kinetic gait assessment, subjective evaluation scores, and cubital joint ROM. Evaluations were performed before and on days 2, 4, 7, 15, 22, and 29 after surgery. Radiographs made before and after the surgical procedures were evaluated. RESULTS: Significant differences in peak vertical force and vertical impulse force were not observed between surgery groups (P =.88 and.49, respectively). Joint ROM was not significantly different between groups (P =.09 for flexion and.91 for extension). For all dogs, joint ROM and radiographic evaluations remained normal throughout the study period. Significant differences in subjective lameness scores, weight bearing, or pain were not observed between groups (P >/ or =.19 for all variables). CONCLUSIONS: In this study population, significant differences between dogs undergoing arthroscopy or arthrotomy of the cubital joint with respect to postoperative pain, weight bearing, joint ROM, or temporal improvement of ground reaction forces were not observed. CLINICAL RELEVANCE: The results of this study suggest that postoperative morbidity should not be a factor when making a decision to perform either arthroscopy or arthrotomy for exploration of the medial compartment of the canine cubital joint. 相似文献
995.
J. T. Howard R. E. Baynes J. D. Brooks J. L. Yeatts B. Bellis M. S. Ashwell P. Routh A. T. O'Nan C. Maltecca 《Journal of veterinary pharmacology and therapeutics》2014,37(6):531-541
Drug use in livestock has received increased attention due to welfare concerns and food safety. Characterizing heterogeneity in the way swine populations respond to drugs could allow for group‐specific dose or drug recommendations. Our objective was to determine whether drug clearance differs across genetic backgrounds and sex for sulfamethazine, enrofloxacin, fenbendazole and flunixin meglumine. Two sires from each of four breeds were mated to a common sow population. The nursery pigs generated (n = 114) were utilized in a random crossover design. Drugs were administered intravenously and blood collected a minimum of 10 times over 48 h. A non‐compartmental analysis of drug and metabolite plasma concentration vs. time profiles was performed. Within‐drug and metabolite analysis of pharmacokinetic parameters included fixed effects of drug administration date, sex and breed of sire. Breed differences existed for flunixin meglumine (P‐value<0.05; Cl, Vdss) and oxfendazole (P‐value<0.05, AUC0→∞). Sex differences existed for oxfendazole (P‐value < 0.05; Tmax) and sulfamethazine (P‐value < 0.05, Cl). Differences in drug clearance were seen, and future work will determine the degree of additive genetic variation utilizing a larger population. 相似文献
996.
BACKGROUND: Intensive livestock units frequently produce flies in large numbers that, on migration, cause nuisance to the occupants of neighbouring dwellings. The resolution of such problems is often reliant on the unequivocal identification of the origin of the flies, particularly when several potential sources exist. This study evaluated stable isotope analysis as a method for differentiating adult houseflies (Musca domestica) on the basis of their dietary history so as to determine their likely source. RESULTS: Flies were reared in the laboratory on several substrates, including chicken and cattle manure, laboratory diet and household vegetable waste. Different fly parts (wings, heads and legs) and whole flies were analysed immediately after eclosion and after 10 days. The δ13C and δ15N values for adults that had developed on each diet type were highly distinct. Both isotopic ratios altered markedly after maintaining the flies for 10 days on a diet of cane sugar solution. CONCLUSIONS: Stable isotope analysis readily differentiated flies that had developed on a range of substrates. The technique, therefore, shows potential to be employed to determine the likely source of various nuisance insects, and to contribute to the abatement of such problems. Copyright © 2011 Society of Chemical Industry 相似文献
997.
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999.
Judith L. Fisher William A. Loneragan Erik J. Veneklaas 《Biological conservation》2009,142(2):256-218
Relationships between plant invasion and the soil seed bank in highly diverse fire adapted mediterranean woodlands are poorly understood, yet critical for that ecosystem’s conservation. Within the biodiversity hotspot of southwest Australia we investigated the composition and diversity of the Banksia woodland soil seed bank in good condition (GC), medium condition (MC) and poor condition invaded by the South African perennial species Ehrharta calycina (PCe) and Pelargonium capitatum (PCp). The investigation assessed three questions: (1) Do soil seed banks of invaded sites have fewer germinants of native species and more germinants of introduced (non-native) species than sites with minimal invasion? (2) Do soil seed banks show shifts in ecological functional types with invasion? (3) Is the soil seed bank of introduced species persistent? Native species germinants, mainly shrubs and perennial herbs, were highest in GC sites and least in poorer condition sites suggesting a reduction in their numbers had occurred over time. Introduced germinants were dominated by perennial and annual grasses, and annual herbs. E. calycina had the greatest seed density (8328 germinants m−2). More introduced than native germinants occurred in the litter. Rapid germination of introduced species (30% in week 1) compared to native species (4% in week 1) provides the capacity for their early dominance. A limited native soil seed bank and dominant persistent introduced soil seed bank represent great challenges for the structural and functional conservation and restoration of woodland ecosystems. This study provides key new knowledge, applicable to a wide range of ecosystems, to help formulate conservation protocols to control dominant introduced species and conserve and restore biodiverse-rich woodlands. 相似文献
1000.