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661.
Reversed phase ion-pair liquid chromatographic determination of nicotine in commercial tobacco products. 2. Cigarettes. 总被引:2,自引:0,他引:2
L A Ciolino D B Fraser T Y Yi J A Turner D Y Barnett H A McCauley 《Journal of agricultural and food chemistry》1999,47(9):3713-3717
A reversed phase ion-pair liquid chromatographic method for the determination of nicotine in commercial tobacco products was previously developed and optimized (Ciolino, L. A.; Turner, J. A.; McCauley, H. A.; Smallwood, A. W.; Yi, T. Y. J. Chromatogr. 1999a, 852 (2), 451-463) and provided reliable results for the determination of nicotine in commercial moist snuff (Ciolino, L. A.; McCauley, H. A.; Fraser, D. B.; Barnett, D. Y.; Yi, T. Y.; Turner, J. A. J. Agric. Food Chem. 1999b, 47, 3706-3712). The method uses an aqueous-based sample extraction and provides rapid separation of nicotine from the minor tobacco alkaloids and other commercial tobacco components. In the present work, the method is evaluated for the determination of nicotine in commercial cigarettes and compared to both an official AOAC method for total alkaloids in tobacco (AOAC, AOAC Official Methods of Analysis of AOAC International, 16th ed.; AOAC International: Gaithersburg, MD, 1995; pp 30-31), and a published GC method (Lyerly, L. A.; Greene, G. H. Beitr. Tabakforsch. 1976, 8 (6), 359-361). Good agreement was obtained between the ion-pair LC method and the GC method with relative differences in determined nicotine contents of 0.6 to 5% for a series of commercial and reference cigarettes. 相似文献
662.
CB O''SULLIVAN AJ DART N MALIKIDES RJ RAWLINSON DR HUTCHINS DR HODGSON 《Australian veterinary journal》1999,77(8):501-503
OBJECTIVE: To evaluate nonsurgical management of type II fractures of the distal phalanx in Standardbred horses. DESIGN: Retrospective study of 48 affected horses. RESULTS: Most fractures occurred on the lateral palmar process of the left forelimb or the medial palmar process of the right forelimb; 81% of horses were considered sound enough to return to training and 63% raced. Of those returning to racing, 41% competed in > 10 races, 37% in 2 to 10 races and 22% in only 1 race. There was no difference in performance before and after fracture. Twenty-four of 25 horses had a bar shoe fitted for > 50% of the treatment phase. Of those horses returning to training without a bar shoe, 89% refractured at the same site. Sixty percent of horses returning to training with a bar shoe raced successfully. The total convalescent time, the time rested in a box and the time spelled in a paddock were similar for horses returning to racing and those that did not. The age of the horse had no effect on the ability to return to racing. CONCLUSION: The prognosis for type II fractures of the distal phalanx is guarded. It is advisable to fit a bar shoe on the horse during convalescence. Horses returning to training and racing with a bar shoe appear less likely to refracture the distal phalanx. Those horses that return to racing can perform at a level similar to that prior to fracture. 相似文献
663.
664.
R. A. M. Vreeburg M. Nas B. De Paepe T. Dreo R. A. Gottsberger E. Fornefeld K. Fraser S. Leonard A. C. Le Roux E. T. M. Meekes C. Rivoal L. Smits-Mastebroek J. van Vaerenbergh 《EPPO Bulletin》2020,50(1):177-185
A test performance study (TPS) was organized in 2018 with ten official testing laboratories to evaluate the performance of different real-time PCR tests for the detection of Clavibacter sepedonicus and/or Ralstonia solanacearum in potato tubers. Participants were sent spiked potato extracts with low (0.8–1.2 × 104 cfu mL-1), medium (1.6–2.4 × 105 cfu mL-1) and high (1.6–2.4 × 107 cfu mL-1) bacterial loads, DNA extracts thereof and heel-end cores from symptomatic potato tubers. The four real-time PCR tests in this TPS for detection of C. sepedonicus were considered fit for purpose as principal screening methods. Two real-time PCRs in this TPS were considered fit for purpose as principal screening methods for detection of R. solanacearum. A third real-time PCR missed 23% of the DNA samples from low-level R. solanacearum spikes and is considered not fit for purpose as a principal screening method. Correct identification of spiked samples was lower when DNA extraction from the spiked samples was performed by the participating laboratories, highlighting the importance of appropriate DNA extraction protocols. 相似文献
665.
Effects of dietary Camelina sativa products on digestible nutrient compositions for rainbow trout (Oncorhynchus mykiss)
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J.M. Fraser S.A. Collins Z. Chen S.M. Tibbetts S.P. Lall D.M. Anderson 《Aquaculture Nutrition》2017,23(5):973-982
Two trials were conducted to determine the effect of dietary inclusion of camelina (Camelina sativa) products on their digestible nutrient compositions in rainbow trout. In the first experiment, the following camelina products: full‐fat seed, oil, high‐oil residue meal (HORM), pre‐press solvent‐extracted meal (SECM) and toasted SECM were evaluated. In the second trial, the utilization of SECM, SECM soaked in water (WS), SECM treated with a multicarbohydrase, Superzyme?‐OM, SECM treated with Bio‐Phytase and SECM treated with Superzyme?‐OM and Bio‐Phytase (MIX) was determined. The experimental diets consisted of a basal diet and test ingredient with a ratio of 70:30, except for camelina oil where the ratio was 80:20. In Experiment 1, SECM had the highest level of digestible crude protein (352 g kg?1), whereas the oil was the best source of digestible energy (8,063 kcal kg?1) and digestible crude fat (908 g kg?1). In Experiment 2, there were no significant differences in nutrient digestibility of SECM and HORM; however, WS and MIX had significantly more digestible dry matter and digestible crude fat than SECM and HORM. Camelina by‐products have the potential to replace fishery by‐products in rainbow trout feeds. 相似文献
666.
1. This paper describes the discovery of a crucian carp Carassius carassius in Loch Rannoch, a species previously not recorded in this loch and only recorded in Scotland from five other lochs. 2. Establishment of fish species in a water body previously not containing that fish species can result in significant detrimental ecological changes within that water body, and once made, introductions are irreversible. 3. Given that such introductions are occurring with increased frequency it is recommended that (a) legislation is introduced to outlaw such translocations, and (b) parties with an interest in freshwater fish are educated to regard such translocations as unethical. ©1997 John Wiley & Sons, Ltd. 相似文献
667.
William D. Dijak Brice B. Hanberry Jacob S. Fraser Hong S. He Wen J. Wang Frank R. ThompsonIII 《Landscape Ecology》2017,32(7):1365-1384