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981.
I'm Gary White, an Equine practitioner from Sallisaw, Oklahoma. I also own a contract research company and do consulting for pharmaceutical companies, and I've been in practice for 26 years.

I'm Dr Joe Bertone, Professor of Equine Medicine Western University of Health Sciences, College of Veterinary Medicine. I am a member of the AVMA Council on Biologic and Therapeutic Agents representing Equine Practice. I spent 5 years as a veterinary medical officer at the FDA Center for Veterinary Medicine.

I'm Dr Bob Stenbom, I'm the manager of Equine Professional Services for Boehringer Ingelheim Vetmedica. I was a practitioner for 14 years before coming to the industry 11 years ago.

I'm Wayne McIlwraith, Professor of Surgery and Director of Orthopedic Research at Colorado State University.

I'm Rick Mitchell, I'm a private practitioner in a group referral practice in Newtown, Connecticut. We are basically devoted to the sport horse. I've served on numerous association committees regarding the regulation of sport horse activities in the USAE, FEI, and have advised numerous drug companies on product development.  相似文献   

982.
983.
Increasing fertiliser use in agricultural landscapes is likely to threaten the viability of remnant native vegetation in many parts of the world. Australia’s prime grain production landscapes have nutrient poor soils, which formerly supported semi-arid woodland. The ecological function and capacity for regeneration of these remnants may be particularly susceptible to nutrient enrichment. The key sources of nutrients are wind and water deposition from crop fertilisation, and manure and feed from sheep. We hypothesised that these sources would result in unequal deposition of nutrients within and among remnant vegetation patches. We surveyed soil nutrients (Total N, Available P and K, C:N ratio, and soil pH) in the edges and interiors of 60 remnant woodland patches of various sizes, and in adjacent cultivated paddocks. Nutrient load was negatively correlated with remnant size and patterns were particularly strong for available P. Small remnant patches (<3 ha) were accumulation zones for nutrients, with levels comparable or higher than within crop lands. The patterns are consistent with the hypothesis that small remnants are strongly enriched as a result of being used for livestock shelter. In larger remnants, the primary cause of enrichment is consistent with edge accumulation of nutrients due to wind and water movement. In large patches, remnant edges, particularly the windward edge, were elevated compared to interiors of large patches. In these semi-arid crop lands, current trends in intensification of cropping and a shift away from livestock may reduce the input of nutrients to small patches but increase the nutrient threat to larger remnants.  相似文献   
984.
Historically, veterinary medical students' mental health has rarely been investigated, but recently there has been renewed interest in this topic. The present study evaluated depression and anxiety levels in a cross-sectional investigation of 93 first-year veterinary medical students enrolled at Kansas State University (KSU). During their first semester, students completed the Center for Epidemiological Studies Depression Scale (CES-D) and the Mental Health Inventory's Anxiety Scale (MHI-A). Results indicate that 32% of these first-year KSU veterinary students were experiencing clinical levels of depressive symptoms. Additionally, students reported elevated anxiety scores. Predictors of depression and anxiety levels include homesickness, physical health, and unclear instructor expectations. Areas of intervention with a focus on improving veterinary medical student well-being are discussed.  相似文献   
985.
Structure-activity relationships (SARs) for 10 pyrethroids against susceptible, kdr and super-kdr strains of houseflies (Musca domestica L.) were investigated by Principal Components Analysis. In the three strains with kdrLatina' all only slightly to moderately (2.6 to 26-fold) resistant to pyrethroids, no correlation between the structure and Levels of resistance could be discerned. In flies with super-kdr, SARs were influenced by the nature of the alcoholic portion of the ester. Resistance was strongest to esters of a-cyano-3-phenoxybenzyl alcohol (74 to 430-fold) and to permethrin (48 to 55-fold). It was weak (6.2 to 11-fold) to cyclopentenone derivatives, being barely stronger than for flies with kdr (2-6 to 6.3-fold). Two variants of super-kdr (3D and A2) were distinguished on the basis of their differential response to esters of 5-benzyl-3-furylmethanol. It is presumed that kdrLatina, super-kdrA2 and super-kdr3D form an allelic series in which kdrLatina represents ground level insensitivity, and the two super-kdrs the progressive extension of strong resistance to more types of ester. The strong differences in resistance to different pyrethroid esters by super-kdr flies provides scope for improving management of resistance to pyrethroid insecticides and for modifying the SAR of pyrethroids to favour weak resistance.  相似文献   
986.
Organochlorine and heavy metal residues were determined in 103 shorebirds of seven species collected at Corpus Christi, Texas, during the winter of 1976-77 to evaluate their potential effects on population survival, DDE and polychlorinated biphenyls (PCBs) were detected in most samples. Chlordane isomers, dieldrin, toxaphene, and heptachlor epoxide also occurred, but less frequently. In general, organochlorine residues were low in skinned carcasses. Geometric means on a wet weight basis ranged from 0.25 ppm to 4.76 ppm for DDE and from 0.67 ppm to 6.64 ppm for PCBs; residues of the other compounds averaged less than 1 ppm in all instances. Mercury, lead, arsenic and vanadium occurred in all shorebird livers, and selenium and cadmium were detected in all kidneys. Residues of these metals, except selenium, were low in most tissue samples. Selenium averages varied from 1.77 ppm to 5.62 ppm (wet weight) in kidneys; residues in this range may be sufficient to inhibit reproduction or to induce other forms of toxicity, especially at the higher levels.  相似文献   
987.
Organochlorine residues in wings of adult mallards and black ducks were monitored during the 1972-73 hunting season. DDE, DDT, DDD, dieldrin, and polychlorinated biphenyls (PCB's) were present in all samples. Mallard wings from Alabama contained the highest mean levels of DDE, DDT, DDD, dieldrin, and PCB's. Mallards and black ducks from the Atlantic Flyway and mallards from the Pacific Flyway contained significantly lower DDE residues than in 1969-70. Black ducks from the Atlantic Flyway contained significantly less dieldrin than in 1969-70, and mallards in the Central and Pacific Flyways contained significantly lower levels of PCB's. As in 1969-70, DDE residues were lowest in the Central Flyway and highest in the Atlantic Flyway. The average PCB level remained unchanged in the Atlantic Flyway but was higher in the Mississippi Flyway than in 1969-70, probably because of the unusually high levels in Alabama samples. All organochlorine residues in black ducks from the Atlantic Flyway significantly correlated. DDE concentrations in mallards from the Atlantic Flyway significantly correlated with those of DDT, DDD, and PCB's.  相似文献   
988.
Whole genome sequencing of a copper resistant (CuR) black rot strain of Xanthomonas campestris pv. campestris (Xcc) isolated from a broccoli plant in Trinidad revealed a unique operon for copper resistance. The cop genes of strain Xcc-BrA1 were determined to be present on a 160 to 180 kb plasmid shown to be non-conjugative with other xanthomonads. While nucleotide comparison of a putative 8.0 Kbp copLABMGF gene cluster identified in Xcc-BrA1 genome did not reveal any homologous region with other known CuR Xanthomonas strains from diverse origins, the comparison of the translated amino acid sequence indicated similarity with X. citri, X. c. pv. citrumelonis and X. vesicatoria Cop proteins. Cloning of the copLAB gene cluster from Xcc-BrA1 conferred copper resistance to other copper-sensitive xanthomonads. Although Xcc-BrA1 harbors copLAB genes with similar sizes and organization and is able to grow on Cu-amended medium as other CuR xanthomonads, the phylogenetic analysis of nucleotide sequences indicates that the cop cluster in Xcc-BrA1 is unique and distantly related to other copLAB genes from Xanthomonas and Stenotrophomonas. The origin of copper resistance genes in Xcc-BrA1 is likely a result of horizontal gene acquisition from a still unknown phylloplane cohabitant. The findings of this study have implications for the management of crop diseases caused by CuR xanthomonads. Future studies could focus on and determining the distribution, overall importance and appropriate control measures for strains harbouring these unique genes.  相似文献   
989.
This retrospective study reviews the medical records of 301 reptiles with dermatological lesions that were examined at the Veterinary Medical Teaching Hospital, University of California at Davis (VMTH-UCD) and the Unité de Dermatologie-Parasitologie-Mycologie, Ecole Nationale Vétérinaire de Nantes (UDPM-ENVN) from 1 January 1992 to 1 July 2008. The most common reptile groups differed between the two hospitals, with lizards being the most common at the VMTH-UCD and chelonians at the UDPM-ENVN. At the VMTH-UCD, boa constrictors (Boa constrictor), ball pythons (Python regius) and other Python species were over-represented, and box turtles (Terrapene carolina) were under-represented in the dermatological lesion caseload. When institutional data were combined, 47% of all reptiles at both institutions with confirmed or suspected cases of sepsis had petechiae, with the highest association seen in chelonians at 82%. Dependent on institution and reptile group, from 29% to 64% of the cases had underlying husbandry issues. Sixty-two per cent of all cases were alive at final status. Veterinarians treating reptiles with skin disease should be aware of the following: (i) that boa constrictors and Python species may be predisposed to dermatological lesions; (ii) that client education is important for proper husbandry; and (iii) that there is a possible association between petechiae and sepsis, especially in chelonians. The conjectural association between certain skin lesions and sepsis remains to be confirmed by systematically derived data that demonstrate a causal relationship between the two.  相似文献   
990.
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