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Journal of Soils and Sediments - Arsenic (As) is one of the most widespread toxic elements, affecting human health through consumption of contaminated water or food. This work studied the effects...  相似文献   
996.
Scab (Venturia effusa) is the major cause of economic loss in pecan in the south-eastern USA. We explored population genetic diversity and structure among orchards of cv. Desirable and native seedlings, and within-orchard variability among trees of all cultivars sampled. We compared the ability of 30, 15 and 7 previously developed microsatellites to characterize the population genetic diversity and structure of V. effusa. Analyses of molecular variance (AMOVA) provided little evidence of structure dependent on cultivar, but there was some evidence of structure between orchards of a cultivar based on distance. Individual orchard AMOVA showed that three of 11 orchards had between-tree population structure. Among six populations from cv. Desirable, a Mantel test showed that geographic distance was related to the pairwise genetic divergence (R2 = 0.84). Among 11 orchards of various cultivars there was little difference in diversity using 30, 15 or 7 markers, or population structure based on AMOVA. Some minor differences in population structure were seen based on discriminant analysis of principal components, or dendrograms. Thus, depending on the objectives, future studies may use as few as 15 or 7 markers without losing ability to discern population genetic diversity or structure. More populations exhibited linkage disequilibrium when using 15 or 30 markers compared to when using seven markers. Knowledge of population genetics of V. effusa in relation to host genotype is needed to understand pathogen population interactions and gene flow, knowledge that will help underpin future breeding efforts to develop durable resistance in this long-lived orchard tree.  相似文献   
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Australian veterinary classrooms are increasingly diverse and their growing internal diversity is a result of migration and large numbers of international students. Graduates interact with other students and increasingly with clients whose attitudes, beliefs, values, and behaviors differ from their own. An understanding and respect for these differences has an impact on client communication and health care outcomes. The present study explored how students understand and are likely to deal with issues of cultural diversity in veterinary professional practice as well as the educational needs that students feel should be met in regard to preparation to engage productively with diversity in professional practice. The present study also explored the extent to which the rich diversity of the undergraduate student population constitutes an educational resource. A class of final-year veterinary students was invited to participate in a workshop exploring intercultural confidence in veterinary consultation. Twelve groups of six to eight students discussed a fictitious scenario involving a challenging clinical encounter with a client from a different culture. Students were reticent to see the scenario in terms of cultural difference, although they generally recognized that awareness of cultural issues in veterinary practice was important. They also tended to not see their own ethnicity as relevant to their practice. While some felt that veterinary practice should be culture blind, most recognized a need to orient to cultural difference and to respond sensitively. Their suggestions for curricular improvements to address these issues are also included.  相似文献   
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Healthy, purpose-bred laboratory beagle dogs that had not been exposed to ticks and were seronegative for Borrelia burgdorferi and Anaplasma phagocytophilum were randomly assigned to four groups of eight dogs each. Control group 1 was not treated. Groups 2, 3 and 4 were treated with a single topical application of a new formulation of fipronil, amitraz and (S)-methoprene (CERTIFECT?, Merial Limited, GA, USA) at 28, 21 or 14 days prior to tick infestation, respectively. Each dog was infested with 25 female and 25 male field-collected adult Ixodes scapularis ticks that had infection rates of 66% for B. burgdorferi sensu stricto and 23% for A. phagocytophilum, as determined by polymerase chain reaction. Two and five days after tick infestation, control dogs had an average of 9.5 and 13.9 attached adult female ticks, respectively, whilst the 24 treated dogs remained tick-free aside from a single tick on the 2nd day after infestation. Serial serological tests demonstrated that the ticks successfully infected 8/8 control dogs with B. burgdorferi and co-infected 6/8 with A. phagocytophilum. B. burgdorferi infection also was confirmed in most control dogs by culture (6/8) and PCR (7/8) of skin biopsies. In contrast, CERTIFECT protected all 24 treated dogs against infection by both B. burgdorferi and A. phagocytophilum, as demonstrated by their negative serological tests throughout the study and the absence of any positive skin biopsy culture or PCR in these dogs.  相似文献   
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Objective: To describe peritoneal drain fluid volume, fluid cytology, and blood‐to‐peritoneal fluid lactate and glucose concentration differences after exploratory celiotomy in normal dogs. Study Design: Prospective study. Animals: Healthy Beagle dogs (n=10). Methods: After exploratory celiotomy, a peritoneal drain was placed, and peritoneal fluid was recorded every 6 hours for 7 days. Fluid was submitted for cytologic examination, and fluid and blood glucose and lactate concentrations were recorded every 12 hours. On day 7, drains were removed and drain tips submitted for aerobic bacterial culture. Results: Mean peritoneal fluid volume decreased from 2.8 mL/kg/day (day 1) to 0.6 mL/kg/day (day 7). All dogs had degenerate neutrophils in peritoneal fluid throughout the 7 days. Four dogs developed contaminated drains. Blood‐to‐peritoneal glucose concentration differences>20 mg/dL occurred after day 4. By day 7, 5 of 7 dogs with patent drains had blood‐to‐peritoneal lactate concentration differences70% of dogs had differences consistent with septic peritonitis each day. Postoperative blood‐to‐peritoneal fluid glucose and lactate difference may not be reliable indicators of septic peritonitis when evaluating abdominal fluid collected with closed suction drains.  相似文献   
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