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Roy Greenhalgh J. David Miller Gordon A. Neish H. Bruno Schiefer 《Applied microbiology》1985,50(2):550-552
The isolation and characterization of 10 isolates of six Fusarium spp. from plant and soil samples collected in Southeast Asia is reported. The ability of these isolates to produce trichothecenes both in liquid cultures (CZ, GYEP, and MYRO) and on rice was assessed, and their toxigenic potential was examined by skin assay and gavage studies with culture filtrates. Although culture filtrates of all the isolates caused minor damage to test animals, only that of F. equiseti DAOM 189762 produced trichothecenes. 相似文献
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- Freshwater conservation is vital to the maintenance of global biodiversity. Ponds are a critical, yet often under‐recognized, part of this, contributing to overall ecosystem functioning and diversity. They provide habitats for a range of aquatic, terrestrial, and amphibious life, often including rare and declining species.
- Effective, rapid, and accessible survey methods are needed to enable evidence‐based conservation action, but freshwater taxa are often viewed as “difficult”—and few specialist surveyors are available. Datasets on ponds are therefore limited in their spatiotemporal coverage.
- With the advent of new recording technologies, acoustic survey methods are becoming increasingly available to researchers, citizen scientists, and conservation practitioners. They can be an effective and noninvasive approach for gathering data on target species, assemblages, and environmental variables. However, freshwater applications are lagging behind those in terrestrial and marine spheres, and as an emergent method, research studies have employed a multitude of different sampling protocols.
- We propose the Pond Acoustic Sampling Scheme (PASS), a simple protocol to allow a standardized minimal sample to be collected rapidly from small waterbodies, alongside environmental and methodological metadata. This sampling scheme can be incorporated into a variety of survey designs and is intended to allow access to a wide range of participants, without requiring complicated or prohibitively expensive equipment.
- Adoption of this sampling protocol would enable consistent sound recordings to be gathered by researchers and conservation organizations, and allow the development of landscape‐scale surveys, data sharing, and collaboration within an expanding freshwater ecoacoustic community—rather than individual approaches that produce incompatible datasets. The compilation of standardized data would improve the prospects for effective research into the soundscapes of small waterbodies and aid freshwater conservation efforts.
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J. K. Hawkey I. S. L. Loudon G. P. Greenhalgh G. T. Bungay 《BMJ (Clinical research ed.)》1971,4(5788):667-670
A new concept for filing medical records in general practice is described, based on an A4-size folder; in experimental use in 40 practices doctors were generally in favour of the new system. 相似文献
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Twelve mature wethers were used in an experiment of change-over design to determine the effect of complete diet feeding on intake and digestibility of diets based on alkalitreated straw and a concentrate containing rolled barley and extracted soya bean meal. Two diets were used: D1 with a 50:50, and D2 with a 75:25 ratio of straw:concentrates on a dry matter basis. The straw and concentrates of each diet were given either separately (S) or as a complete diet (C). Complete diets gave a slightly, but not significantly higher intake (C, 86.5) and S, 82.5 g dry matter /kg W0.75 per day). The separate method gave a significantly higher digestibility coefficient for dry matter (C, 62.2 and S, 65.5; P < 0.05) and for crude fibre (C, 57.2 and S, 62.5; P < 0.01). Water intake increased by 42.7 ml g?1 Na derived from NaOH. There were no significant interactions between the method of feeding and the type of diet in intake and digestibility of the diets or in the intake of water. 相似文献
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The fall in ankle systolic pressure after exercise serves as an objective indicator of the severity of haemodynamically important peripheral arterial disease. Twenty-six patients were studied to establish the effects of different work loads on the pressure response and to develop a test to standardise these effects. The patients walked for one or two minutes at 4 km/h and one or two minutes at 6 km/h, and the fall in pressure was the same when measured immediately after exercise. The time taken for the pressure to return to the pre-exercise value varied. As the fall in pressure occurs after only one minute of exercise at 4 km/h on a 10% slope, this might be adopted as a standard test. It is acceptable to the patient, since claudication, angina, and shortness of breath rarely occur. It is sensitive enough to detect mild or asymptomatic disease and is useful in following up patients. 相似文献
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L Fritsche T Greenhalgh Y Falck-Ytter H-H Neumayer R Kunz 《BMJ (Clinical research ed.)》2002,325(7376):1338-1341
ObjectiveTo develop and validate an instrument for measuring knowledge and skills in evidence based medicine and to investigate whether short courses in evidence based medicine lead to a meaningful increase in knowledge and skills.DesignDevelopment and validation of an assessment instrument and before and after study.SettingVarious postgraduate short courses in evidence based medicine in Germany.ParticipantsThe instrument was validated with experts in evidence based medicine, postgraduate doctors, and medical students. The effect of courses was assessed by postgraduate doctors from medical and surgical backgrounds.InterventionIntensive 3 day courses in evidence based medicine delivered through tutor facilitated small groups.ResultsThe questionnaire distinguished reliably between groups with different expertise in evidence based medicine. Experts attained a threefold higher average score than students. Postgraduates who had not attended a course performed better than students but significantly worse than experts. Knowledge and skills in evidence based medicine increased after the course by 57% (mean score before course 6.3 (SD 2.9) v 9.9 (SD 2.8), P<0.001). No difference was found among experts or students in absence of an intervention.ConclusionsThe instrument reliably assessed knowledge and skills in evidence based medicine. An intensive 3 day course in evidence based medicine led to a significant increase in knowledge and skills.
What is already known on this topic
Numerous observational studies have investigated the impact of teaching evidence based medicine to healthcare professionals, with conflicting resultsMost of the studies were of poor methodological qualityWhat this study adds
An instrument assessing basic knowledge and skills required for practising evidence based medicine was developed and validatedAn intensive 3 day course on evidence based medicine for doctors from various backgrounds and training level led to a clinically meaningful improvement of knowledge and skills 相似文献10.
CJ Cooksey 《Biotechnic & histochemistry》2016,91(6):438-444
Malachite green was discovered independently by two researchers in Germany in the 19th century and found immediate employment as a dye and a pigment. Subsequently, other uses, such as staining biological specimens, emerged. A much later application was the control of fungal and protozoan infections in fish, for which the dye remains popular, although illegal in many countries owing to a variety of toxicity problems. In solution, malachite green can exist as five different species depending on the pH. The location of the positive charge of the colored cation on a carbon atom or a nitrogen atom is still debated. The original names of this dye, and their origins, are briefly surveyed. 相似文献