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51.
52.
DNA from a replication-defective spleen focus-forming virus (SFFV) was reconstructed and transfected into psi-2 cells containing a packaging-defective mutant of Moloney murine leukemia virus. Replication-incompetent retrovirus particles (helper virus-free containing genomes that express the transforming envelope gene of SFFV (gp52) transformed bone marrow cells in vitro and, after direct intravenous introduction of the vector, induced malignant erythroid disease in vivo. Disease induction was dependent on prior treatment of mice with phenylhydrazine, which probably increased the availability of erythroid target cells. Since there was no evidence of virus particle expression in mice with malignant disease, this study demonstrates the acute oncogenic potential of a limited number of erythroid cells expressing SFFV gp52. Direct inoculation of animals with nonreplicating retroviral vectors containing transforming genes may be useful in study the oncogenic effects of such genes.  相似文献   
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Abstract

The occurrence of a disease of annato apparently restricted to the pods is reported, and is caused by a Colletotrichum state of Glomerella cingulata.  相似文献   
54.
Abstract

Leaf scald of rice (Rhynchosporium oryzae Hashioka &; Yokogi) is reported from Brunei. The influence of cultivation system and fertiliser regime on the severity of the disease is discussed. The presence of adequate nitrogen appears to increase the severity of the disease. Leaf scald has the potential of becoming a serious threat to rice in the area.  相似文献   
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ABSTRACT

Case history: Two dogs presented separately to the Small Animal Hospital, University of Florida (Gainsville, FL, USA) for ingestion of ibuprofen. The first dog ingested 561.8?mg/kg ibuprofen in addition to paracetamol and caffeine and vomited prior to admission. This patient also received fluid therapy for 8 hours prior to charcoal haemoperfusion. The second dog ingested 500?mg/kg of ibuprofen and the owners induced vomiting with hydrogen peroxide prior to presentation. Due to the severity of clinical signs, both patients were treated with charcoal haemoperfusion.

Clinical findings: The concentrations of ibuprofen in the blood of the dogs prior to treatment were 478 and 301?mg/L. During the treatment ibuprofen concentrations were reduced by 95.8% and 45.5%, respectively, with no treatment side effects and minimal clinical signs after treatment.

Diagnosis: Toxicity due to ingestion of ibuprofen toxicity that was successfully treated with charcoal haemoperfusion.

Clinical relevance: In the cases described here minimal benefit was seen after 3 hours of treatment using one haemoperfusion cartridge. This is in contrast to a previously published report in which dogs were treated for 6 hours with two charcoal haemoperfusion cartridges. This suggests that one cartridge may be sufficient. The amount of ibuprofen ingested was not a reliable predictor of the concentration in blood at the initiation of treatment. Charcoal haemoperfusion is an effective means of reducing plasma concentrations of ibuprofen, however, its use may be limited by its cost and availability.  相似文献   
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Zoonotic diseases are an ever-present concern in small animal veterinary practice and are often overlooked. A variety of nonparasitic zoonotic diseases may be encountered in small animal practice, including cat scratch disease (bartonellosis), cat bite abscesses, rabies, leptospirosis, methicillin-resistant Staphylococcus aureus, Clostridium difficile-associated diarrhea, salmonellosis, avian chlamydiosis, campylobacteriosis, dermatophytosis, and blastomycosis. These may cause human disease ranging from mild and self-limiting to fatal. The risk of development of a zoonotic disease can be lessened by early recognition of infected animals, proper animal handling, basic biosecurity precautions, and, most importantly, personal hygiene.  相似文献   
58.
1. Traditionally, the living and nonliving natural resources of the coastal waters of The Netherlands have been exploited. Part of this exploitation took the form of embankment and reclamation to produce new agricultural land. 2. The first nature reserve within the coastal waters was established in 1916. After this year the number of coastal nature reserves gradually increased. However, until about 1970 the status of a nature reserve provided little protection when other interests claimed the same area. 3. In the period 1965–1980 the situation changed drastically. The Dutch government took far-reaching decisions with regard to the protection of the Wadden Sea and the Oosterschelde estuary. 4. At the start of this century about 10 000 km2 of coastal waters existed between the mainland coast and the three-miles territorial border of The Netherlands. Of these, 4500 km2 have been embanked and reclaimed or changed into freshwater lakes, 4000 km2 have protected status, and about 1500 km2 within the former three-miles zone and in the Westerschelde estuary (250 km2) are still unprotected. 5. The present situation with regard to the conservation of coastal waters in The Netherlands is largely due to private initiatives. Scientists played an active part in the conservation movement by providing information, especially in the early phases of this development. © 1997 John Wiley & Sons, Ltd.  相似文献   
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