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51.
Glyphosate-resistant Lolium multiflorum in Chilean orchards   总被引:7,自引:0,他引:7  
Summary Lolium multiflorum (Italian ryegrass) seeds suspected of being resistant to glyphosate were collected from fruit orchards at two locations, San Bernardo (SB) and Olivar (OL), Chile, that had been treated an average of three times per year with the isopropylamine salt of glyphosate during the previous 8–10 years. Laboratory experiments were conducted for each orchard population and a susceptible population, a commercial cultivar called Tama (TM), using Petri dishes containing filter paper saturated with 5 mL of glyphosate solution (0–160 mg a.e. L−1) . Pot dose–response experiments were also conducted in the greenhouse. The three L. multiflorum populations were treated with glyphosate (0.00–4.32 kg a.e. ha−1). The dose needed to reduce shoot length (Petri dish experiment) and fresh weight (pot dose–response experiment) by 50% was determined for each population. Compared with the TM population, the Petri dish experiment found that the SB and OL populations were five- and sixfold, respectively, more resistant to glyphosate, whereas the pot dose–response experiment found that the SB and OL populations were two- and fourfold, respectively, more resistant to glyphosate. These results confirm a new case of glyphosate resistance in a novel species, L. multiflorum , and correspond to the first case of glyphosate resistance reported from South America.  相似文献   
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The prevention and management of pain is fundamental to the practice of both human and veterinary medicine. The recognition and treatment of pain represents an important indicator of the quality of care delivered in human hospitals and veterinary hospitals. Yet, both human and veterinary health care professionals have cited inadequate knowledge as a significant barrier to effective pain management. The aims of this pilot study were twofold: (1) to gauge veterinary medical students' current attitudes regarding their training in pain management and (2) to assess the impact of training and practice on the use of a canine acute pain assessment teaching tool. Participants, third-year professional veterinary medical students, completed a 16-item survey questionnaire before a 30-minute training session on pain assessment using the teaching tool and completed it again after training and a one-week practice period. Questions related to canine pain, assessment of canine pain, pain management education in the professional veterinary curriculum, and an example case presentation (video) were included in the survey. The analysis of survey results indicated that professional veterinary medicine students find value in didactic and clinical training in canine pain assessment. Additionally, use of the canine acute pain teaching tool in conjunction with a training program improved students' knowledge and skill in assessment while pointing out the importance of further training. Differences with regard to gender and tracking were found and warrant further exploration.  相似文献   
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US veterinary students are subject to significant stress throughout their veterinary education. In this article, the authors characterize the use of over-the-counter (OTC) medications and relate their use to stress in a veterinary student population. Of the students sampled, 35% were OTC medication users; 33% of these were regular OTC medication users. Forty-three percent of students were energy drink (ED) users; 45% of these were regular ED users. OTC medication users had significantly higher stress scores than non-OTC medication users, and ED users had significantly higher anxiety scores than non-ED users. The most common reasons for use given by OTC medication users were to help with studying and to fall asleep at night. Depression scores were significantly higher for juniors and sophomores than for freshmen. Depression, stress, and anxiety scores were all lower in the Colorado State University students when compared with the University of Georgia students. OTC medication and ED veterinary student users had distinct characteristics that differed from those of nonusers. Users suffered from more stress and anxiety and had more difficulties with sleep, which may have affected their overall health and academic performance. Educating veterinary students about the consequences of using OTC medication and ED and providing counseling support may be of benefit to veterinary students' psychological well-being.  相似文献   
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BACKGROUND: Flumioxazin is a soil-applied herbicide recommended for broadleaf weed control in soybeans and peanuts, and was recently introduced for vineyard weed management. Considering the limited information available in relation to flumioxazin field soil behaviour, the main objectives of this study were to determine the persistence, adsorption and movement of flumioxazin in soil in four Chilean vineyard production areas. RESULTS: DT(50) values ranged from 10.6 +/- 1.0 to 32.1 +/- 3.1 days between localities, being correlated with rain events, time between herbicide application and first heavy rain event, and soil pH. Flumioxazin soil residue found at 90 days after application (DAA) varied from 9.6 to 24.9% of the initial amount applied, and depended on the total rainfall amount that occurred during the first 90 DAA. Herbicide leaching below 15 cm was approximately 45% of the flumioxazin detected at 90 DAA in the whole soil profile. Flumioxazin maximum leaching soil depth was 45 cm at all locations. K(d) values varied from 2.54 to 6.51 mg L(-1), depending on localities and soil profile depth, and correlated positively with organic carbon and clay content. CONCLUSIONS: These results indicate that flumioxazin is a herbicide with low environmental risk owing to its short DT(50), reduced soil residues 3 months after application and low effective dose.  相似文献   
56.
The use of complementary and alternative medical therapies is becoming widespread. The objective of this study was to examine the use of complementary and alternative therapies in dogs and cats with cancer. The types of modalities used, the intended purpose for each modality, sources of information pet owners used, and the level of interest in these modalities were all evaluated. Information was obtained by written survey, and 254 owners agreed to participate. Complementary and alternative therapy use was commonplace, with 76% of surveyed owners reporting some use. When prayer for health reasons was excluded, the number of owners reporting use dropped to 65%. Nutritional supplements were the most commonly used therapy.  相似文献   
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Summary A comparison has been made in 9- to 10-month-old castrated male Merino sheep of the changes in plasma total cortisol concentration and behaviour after being treated by either the modified Mules operation or by topical application of a quaternary ammonium compound to achieve non-surgical mulesing. After surgical mulesing, plasma total cortisol concentration increased immediately and rapidly and reached a peak value in 15 minutes, whereas after non-surgical treatment an immediate rise did not occur, but a similar peak value was observed in blood samples collected 24 hours after treatment. The concentrations were lower in both groups at 48 hours. Likewise postural changes indicative of discomfort were immediately apparent in the surgically treated sheep, but not until 3 to 4 hours later in those treated non-surgically. Arena testing revealed that a lasting aversion to the person who restrained them during treatment developed in the surgically mulesed sheep, but not in those treated non-surgically. The non-surgical procedure did not create large open wounds, as did the surgical operation, but still achieved similar enlargement of the bare area on the breech, and healing was quicker in the non-surgically treated sheep.  相似文献   
58.
Three PCR primer pairs, based on the cytokinins (etz) or IAA biosynthetic genes, were used for detecting Erwinia herbicola pv. gypsophilae in Gypsophila paniculata plants. The primers were specific to all gall-forming E. herbicola strains and distinguished them from saprophytic strains associated with gypsophila plants or from other gall-forming bacteria. In pure culture of the pathogen, less than one bacterial cell was detected with nested PCR using the etz primers - an increase of 100-fold in sensitivity as compared with single-round PCR. In the presence of plant extract a reduction of tenfold in sensitivity was observed by nested PCR. When cells were grown on a semi-selective medium prior to PCR (Bio-PCR), five cells from pure culture of the pathogen were detected. The bacteria could be detected by nested-PCR or Bio-PCR in symptomless gypsophila cuttings after 7 days. The Bio-PCR procedure described in this study can be used to establish disease-free nuclear stock of mother plants of gypsophila.  相似文献   
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The effects of translucent polyethylene sheeting as a thermal covering to eradicate Pueraria montana (kudzu) were investigated at Clemson, South Carolina on a clay loam. In 2005, the highest reduction of live root crowns was observed where P. montana was covered for the entire growing season (May–October) with a reduction of 42% of live root crowns compared with the control plots. Where P. montana was covered for alternate weeks throughout the growing season live root crowns were reduced by 35%. Covering P. montana for one week and then uncovering for four weeks repeatedly through the season killed 24% of root crowns. In 2006, the second year of treatment to the same plots, the three solarization treatments had similar efficacy of about 97%. The use of polyethylene sheeting appears not to be cost‐effective for general control of large P. montana infestations, but may be useful for small patches.  相似文献   
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