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Abstract. Inputs of acidity to the ground arise through two distinct routes: wet deposition which includes all acidity deposited in rain and snow and dry deposition, the direct sorption of SO2 , NO2 or HNO3 gases by vegetation or soil surfaces. The acidity from dry deposition of SO2 and NO2 is created during the oxidation of deposited SO2 and NO2 to SO2 4 and NO3 − respectively. The areas of Britain experiencing the largest wet deposition of acidity are the high rainfall areas of the west and north, in particular the west central highlands of Scotland, Galloway and Cumbria where inputs exceed 1 kp H+ ha−1 annually. Wet deposited acidity in the east coast regions of Britain is in the range 0.3–0.6 kg H+ ha−1 a−1 . Monitoring data for rainfall acidity at rural sites throughout northern Britain show a decline in deposited acidity of about 50% during the last six years. Dry deposition is largest in the industrial midlands and southeast England and in the central lowlands of Scotland, where concentrations of SO2 are largest. In these regions the dry deposition of SO2 following oxidation may lead to acid inputs approaching 3 kg H+ ha−1 a−1 and greatly exceeding wet deposition. 相似文献
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Prognostic factors for tumor remission and survival in dogs after surgery for primary lung tumor: 76 cases (1975-1985) 总被引:1,自引:0,他引:1
G K Ogilvie R M Weigel W M Haschek S J Withrow R C Richardson H J Harvey R A Henderson J D Fowler A M Norris J Tomlinson 《Journal of the American Veterinary Medical Association》1989,195(1):109-112
The association of various prognostic factors with remission and survival after the excision of lung tumors was evaluated in 76 dogs. Overall, the median survival time of treated dogs was 120 days; 72% had tumor that underwent remission (median duration of remission, 120 days). Dogs with tumors that underwent remission had significantly (P = 0.001) increased survival time (median, 330 days vs 28 days for dogs with tumors that did not undergo remission). The finding of normal-sized lymph nodes at the time of therapeutic thoracotomy was significantly (P = 0.001) correlated with increased remission probability (85.4% remission rate vs 43.6% in dogs with large lymph nodes). Use of various diagnostic methods to find normal regional lymph nodes before surgery indicated that such finding was significantly (P less than or equal to 0.01) correlated with increased remission duration (median remission duration, 365 days, vs 60 days for tumors in dogs with large lymph nodes), and the finding of normal lymph nodes at the time of surgery was significantly (P less than or equal to 0.01) correlated with increased survival time (median, 345 days, vs 60 days for dogs with large lymph nodes). 相似文献
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Comparison of 2 Doses for ACTH Stimulation Testing in Dogs Suspected of or Treated for Hyperadrenocorticism
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N. G. Fowler 《The Journal of small animal practice》1964,5(1):39-43
Abstract— The paper reviews the humanitarian, clinical and public relations roles of the practising veterinary surgeon when dealing with an accident case.
Résumé— L'article examine les rôles humanitaire, clinique et de propagande du praticien vétérin-aire lorsque celui-ci a affaire à un accident.
Zusammenfassung— Dieser Vortrag handelt von der menschenfreundlichen und klinischen Rolle des praktischen Tierarztes und von seiner Beziehung zur Öffentlichkeit, wenn er ein bei einem Unfall verletztes Tier behandelt. 相似文献
Résumé— L'article examine les rôles humanitaire, clinique et de propagande du praticien vétérin-aire lorsque celui-ci a affaire à un accident.
Zusammenfassung— Dieser Vortrag handelt von der menschenfreundlichen und klinischen Rolle des praktischen Tierarztes und von seiner Beziehung zur Öffentlichkeit, wenn er ein bei einem Unfall verletztes Tier behandelt. 相似文献
80.
Oleoresin flow is an important factor in the resistance of pines to attack by southern pine beetle, Dendroctonus frontalis Zimm., and its associated fungi. Abiotic factors, such as nutrient supply and water relations, have the potential to modify this plant-insect-fungus interaction; however, little is known of the effects of inoculation with beetle-associated fungi on oleoresin flow. We observed that constitutive and induced resin yield in loblolly pine, Pinus taeda L., were affected by either fungal inoculation (with the southern pine beetle-associated fungus Ophiostoma minus (Hedgcock) H. & P. Sydow) or silvicultural treatment. The effects of mass wounding (400 wounds m(-2)) and mass wounding and inoculation with O. minus were assessed by comparison with untreated (control) trees. The treatments were applied to trees in a 2 x 2 factorial combination of fertilizer and irrigation treatments. Fertilization did not significantly affect constitutive resin yield. Even as long as 105 days post-treatment, however, mass-inoculated trees produced higher induced resin yields than control or wounded-only trees, indicating a localized induced response to fungal inoculation. We noted no systemic induction of host defenses against fungal colonization. Although beetles attacking previously attacked trees face a greater resinous response from their host than beetles attacking trees that had not been previously attacked, the effect of an earlier attack may not last more than one flight season. Despite mass inoculations, O. minus did not kill the host trees, suggesting that this fungus is not a virulent plant pathogen. 相似文献