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Cristina Cruz S. Herman Lips Maria Amelia Martins‐Loucao 《Journal of plant nutrition》2013,36(8):1517-1530
The response of carob (Ceratonia siliqua L.) seedlings grown at different root zone temperatures affected by nitrate and ammonium nutrition was studied. When root temperatures ranged from 10 to 35°C, ammonium‐fed plants were significantly larger than nitrate‐fed plants. Ammonium‐fed plants displayed toxicity symptoms and were much smaller at 40°C root temperature in comparison with the nitrate‐fed plants grown at the same root temperature. Root/shoot ratio slightly increase with root temperature in ammonium‐ and nitrate‐fed plants in a similar way, and shoot demand per root unit decreased with root temperature between 15 and 25°C. There was a general increase in net photosynthesis with root temperature, though nitrate‐fed plants were more sensitive to low and ammonium‐fed plants to high temperatures. Increasing the root temperature of ammonium fed plants from 10 to 40°C leads to a 30% increase in the amount of photosynthates sent to the roots. The presence of ammonium resulted in the distribution of newly fixed carbon away from carbohydrates and into nitrogen compounds. Potassium, calcium, and nitrogen content of the plants also increased with increasing root temperature. 相似文献
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Virginia Buechner-Maxwell Mark Crisman Michael Murray William Ley Geoffrey Saunders Amelia Walton 《Journal of Equine Veterinary Science》1996,16(9):375-379
Transtracheal wash and bronchoalveolar lavage are diagnostic techniques that have been adopted from human medicine for monitoring inflammatory changes in the airway of the horse. Transendoscopic biopsy has also proven to be a valuable tool for obtaining samples of the airway mucosa in human patients. A transendoscopic technique was developed in this study for obtaining a respiratory mucosal biopsy from standing, sedated horses. Six normal adult horses were sampled at eight-week intervals for a total of three sample periods. Horses were monitored for adverse effects of the technique and none were noted. Sample sites were completely healed after eight weeks with no gross or histologic abnormalities. Biopsy samples were 3 to 4 millimeters in diameter, and 17 of 18 samples provided interpretable histological sections. Methods for handling, staining and evaluating tissue were also developed. The results of this study demonstrated that airway mucosal biopsy is a safe, repeatable technique that can be performed in the sedated, standing horse. 相似文献
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A series of experiments in the laboratory and greenhouse, were designed to test the possible causes of the field resurgence of the aphid Myzus persicae. Stimulation of reproduction occurred at topical dosages of around the LD5 value. Residual film tests indicated a significant depression in fecundity when aphids were held on sub-lethal deposits of fenvalerate, even at dosages below the LD5 value. Trends in the population build-up experiments in the greenhouse suggested there may be some stimulation when aphids are confined to aged deposits of fenvalerate 7 days after treatment, but the slight increase was not significant. 相似文献
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Rioja E Dzikiti BT Fosgate G Goddard A Stegmann FG Schoeman JP 《Veterinary anaesthesia and analgesia》2012,39(6):599-610
ObjectiveTo determine the effects of intravenous (IV) magnesium sulphate (MgSO4) as a bolus followed by a constant rate infusion (CRI) on anaesthetic requirements, neuroendocrine stress response to surgery, haemostasis and postoperative analgesia in healthy dogs undergoing ovariohysterectomy.Study designBlinded randomized clinical trial.AnimalsSixteen female dogs.MethodsAfter intramuscular premedication with acepromazine (0.05 mg kg?1) and morphine (0.3 mg kg?1), anaesthesia was induced with diazepam (0.2 mg kg?1) and propofol (2 mg kg?1) intravenously and maintained with isoflurane in oxygen in all dogs. Dogs were randomly assigned to two groups, M and C. Group M received MgSO4 (50 mg kg?1 over 15 minutes, followed by a 15 mg kg?1 hour?1 CRI). Group C received an equivalent bolus and CRI of lactated Ringer's solution. In addition, all dogs received lactated Ringer's solution (10 mL kg?1 over 15 minutes followed by 10 mL kg?1 hour?1). End-tidal isoflurane and carbon dioxide tensions, cardio-respiratory variables, arterial blood gases, electrolytes, ACTH and cortisol concentrations were measured at different time points. Thromboelastography (TEG) was performed pre- and post-anaesthesia. Postoperative pain was evaluated using the short form of the Glasgow Composite Pain Scale. Data were analysed with repeated measures anova and Mann–Whitney U tests (p< 0.05).ResultsNo statistically significant differences between groups were found in any of the measured variables. However, the alpha angle and maximal amplitude recorded by TEG in group M were significantly increased post-anaesthesia, but remained within the reference interval. One dog in Group M and two in Group C received rescue analgesia during recovery.Conclusions and clinical relevanceAs used in this study, MgSO4 failed to decrease isoflurane requirements, postoperative pain and stress hormone concentrations; however, it did not produce any cardio-respiratory or major haemostatic side effects. Administration of intravenous MgSO4 together with an opioid during ovariohysterectomy in dogs does not seem to provide any clinical advantage. 相似文献
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