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171.
Ackerman LJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(6):185-188,189
Pemphigus and pemphigoid are uncommon dermatological entities in domestic animals and of a presumed autoimmune nature. In one form or another, they have been reported in the dog, cat, horse and goat. Although these diseases are considered to be bullous dermatoses, the clinical presentation may vary from ulcerative to exfoliative to proliferative depending on the individual condition. Currently, four variants of pemphigus are recognized (vulgaris, vegetans, foliaceus, erythematosus) and two of pemphigoid (bullous, cicatricial) although cicatricial pemphigoid has not yet been conclusively demonstrated in animals. Diagnosis is based on history, clinical signs, histopathology and immunopathology. Therapy must be immunosuppressive to be effective and is palliative rather than curative. 相似文献
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Summary. Tracer studies using single drops of solutions containing 3–amino-1,2,4–triazole-5–14 C (aminotriazole-14 C) or 2,2–dichloropropionic acid-2–14 C (datapon-14 C) revealed that in couch plants (Agropyron repens (L.) Beauv.) growing under field conditions in the autumn and at the stage where the aerial shoots were 40–50 cm long, both compounds moved in both symplast and apoplast. Dalapon was less mobile in the symplast than aminotriazole and only negligible amounts of dalapon were translocated to the rhizomes. The nodes of the treated shoots appeared to act as barriers to translocation, a phenomenon more pronounced for dalapon than for aminotriazole.
Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully-expanded leaf.
In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots. 相似文献
Application to a basal green leaf led to a more uniform distribution of the compounds within plants and rhizomes than when the application was made to the youngest fully-expanded leaf.
In couch plants with aerial shoots 10–15 cm long treated in the stubble, the distribution of both aminotriazole and dalapon was mainly restricted to the treated shoots. Even 15 days after application only trace amounts of radioactivity could be found in the rhizomes and untreated shoots. 相似文献
174.
175.
J. L. HAMMERTON 《Weed Research》1967,7(4):331-348
Summary. Seeds of Polygonum persicaria from several sources, or from plants subjected to in lain treatments, were chilled for varying periods and incubated for a 3-week germination test period. Populations differed widely in seed weight and to some extent in the response to different periods of chilling. No relationship between this response and the climate of the locality of origin could be found. There was much variation in seed weight and germination behaviour between individual plants within populations. A total of four polymorphic seed categories were observed. The proportions of seeds in the two main categories varied widely between and within populations, and were affected by certain environmental factors. These factors also appeared to affect the degree of inter-plant variation in seed shape and germination behaviour.
Travaux sur les espàes indésirables du genre Polygonum L. V. Variations dans le poids des semences, leur comportement à la germination et leur polymorphisme chez P. persicaria L. 相似文献
Travaux sur les espàes indésirables du genre Polygonum L. V. Variations dans le poids des semences, leur comportement à la germination et leur polymorphisme chez P. persicaria L. 相似文献
176.
177.
Summary. It is practicable to use herbicides as an alternative to ploughing grass swards for the preparation of a seedbed for the sowing of cereals and kale. The yields of spring barley and kale following a glaass/clover sward killed with 10 lb/ac amitrole-T were similar to those obtained following ploughing. Yields of tip to 40 cwt/ac of winter wheat were obtained following grass swards killed with amitrole-T compared with up to 45 cwt/ac after ploughing.
The ideal herbicide must kill all plants in a sward and have no residual toxicity to the subsequent crop. At 10 lb/ac, amitrole-T killed most plants in the sword, but it was considered necessary to delay sowing for at least 3 weeks after spraying to minimize the danger of residual toxicity. Ploughing gave the lowest incidence of grasses persisting from the sward. Paraquat did not control clover and Agropyron repens , while broad-leaved weeds were more common on the ploughed than on the sprayed land.
There were differences in the amount of nitrogen mineralized in ploughed and In undisturbed soil, but these were insufficient to affect crop yields materially. When a lower yield followed herbicidal destruction of the sward, this was not accompanied by a reduced percentage nitrogen content.
L'emploi des déherbants pour la rénovation des prairies 相似文献
The ideal herbicide must kill all plants in a sward and have no residual toxicity to the subsequent crop. At 10 lb/ac, amitrole-T killed most plants in the sword, but it was considered necessary to delay sowing for at least 3 weeks after spraying to minimize the danger of residual toxicity. Ploughing gave the lowest incidence of grasses persisting from the sward. Paraquat did not control clover and Agropyron repens , while broad-leaved weeds were more common on the ploughed than on the sprayed land.
There were differences in the amount of nitrogen mineralized in ploughed and In undisturbed soil, but these were insufficient to affect crop yields materially. When a lower yield followed herbicidal destruction of the sward, this was not accompanied by a reduced percentage nitrogen content.
L'emploi des déherbants pour la rénovation des prairies 相似文献
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