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91.
92.
The interactive effects of UV-B and insecticide exposure on tadpole survival, growth and development
Because declines within amphibian populations can seldom be attributed to a single cause, it is important to focus on multiple stressors, both natural and anthropogenic. Variables such as UV-B radiation and chemical contamination can interact with one another in ways that might not be predicted from single-factor studies. We exposed southern leopard frog (Rana sphenocephala) tadpoles to the insecticide carbaryl and varying intensities of UV-B radiation in artificial ponds and examined their effects on survival, size at metamorphosis, and the duration of the larval period. Tadpole survival to metamorphosis was positively influenced by UV-B intensity. Tadpoles in ponds exposed to carbaryl contained over three times more algae and yielded larger metamorphs than control ponds. Although previous laboratory studies have indicated carbaryl becomes more toxic in the presence of UV-B, we did not find such an effect, perhaps because of the protection afforded by dissolved organic carbon within the ponds. Our research emphasizes the importance of conducting field studies to more accurately predict what occurs under a natural setting. 相似文献
93.
G. J. Baker R. G. Breeze Christine O. Dawson 《The Journal of small animal practice》1972,13(11):649-653
An oral lesion in a cat caused by the actinomycete Dermatophilus con-golensis is described. Multiple granulomata were present in biopsy material taken from a tongue lesion. After surgical excision and daily penicillin therapy the condition regressed.
Résumé. Une lésion oralle dans un chat, causée par l'actinomycète Dermatophilus congolensis est décrit. Des granulomes multiples étaient présentes dans la substance de la biopsie, prise de la lésion de la langue. Après l'excision chirurgicale et la thérapie journalière de pénicilline, la condition décroissait.
Zusammenfassung. Man beschreibt eine orale Verletzung in einer Katze, die durch den Strahlenpilz Dermatophilus congolensis , verursachet wird. Die multipelen Granulomata waren im Stoff von der Biopsie, Welches von der Verletzung der Zunge, genommen wird. Der Zustand klang ab, nach der chirurgischen Exicision und nach der täglichen Heilung von Penizillin. 相似文献
Résumé. Une lésion oralle dans un chat, causée par l'actinomycète Dermatophilus congolensis est décrit. Des granulomes multiples étaient présentes dans la substance de la biopsie, prise de la lésion de la langue. Après l'excision chirurgicale et la thérapie journalière de pénicilline, la condition décroissait.
Zusammenfassung. Man beschreibt eine orale Verletzung in einer Katze, die durch den Strahlenpilz Dermatophilus congolensis , verursachet wird. Die multipelen Granulomata waren im Stoff von der Biopsie, Welches von der Verletzung der Zunge, genommen wird. Der Zustand klang ab, nach der chirurgischen Exicision und nach der täglichen Heilung von Penizillin. 相似文献
94.
Phorate residues in peat blocks and lettuce were determined following incorporation of the insecticide into different block and ‘Speedling’ cell sizes. Between-block variability was influenced little by block size. Phorate oxidation was most extensive in the largest blocks containing the smallest dose. Total residue concentrations in the lettuce declined from the time of planting to harvest, although accumulation of insecticide continued and was related more to dose than to block or cell size. Residues in the lettuce at harvest exceeded the proposed maximum limit of 0.2 mg kg?1 in some treatments. Residues at planting comprised mainly the parent sulphoxide and sulphone, but by harvest, the oxygen analogue sulphoxide and sulphone predominated. Lettuce weight was not influenced by dose but was related directly to block size. Carbofuran and chlorfenvinphos residues were determined in calabrese sown into two sizes of blocks. At planting time, carbofuran residue concentrations were 100 times greater than those of chlorfenvinphos but residues of both insecticides in the mature heads were < 0.01 mg kg?1. Seedling weights in both sowings declined with increasing concentrations of the insecticides. It was concluded that manipulations of block size and the dose of insecticide need to be evaluated for individual insecticide/crop combinations to exploit the technique fully. 相似文献
95.
Following experimental and commercial applications to soil of a granular formulalation of phorate (O,O-diethyl S-ethylthiomethyl phosphorodithioate), residues in the soil and in lettuce were determined by gas-liquid chromatography. When applied by the bow-wave method as a continuous logarithmically-changing dose ranging from approximately 0.9 to 16.0 kg a.i. ha?1, the proportional rate of oxidation in soil of phorate sulphoxide to phorate sulphone was inversely related to dose. Ten weeks after application, total phorate residues in the soil had declined by about 35% at all dose levels. Residues in mature lettuce, from the 1-5 kg ha?1 dose-range, comprised the parent and oxygen analogue sulphoxides and sulphones; the relative proportions of the individual metabolites were independent of dose. Over this dose-range, total residue concentrations in the crop became proportionally slightly greater with increasing dose. When single doses of 1.1, 2.0 or 2.2 kg a.i. ha?1 were applied at drilling, the total residue concentrations in the lettuce declined from 5 mg kg?1 in seedlings from some treatments to <0.05 mg kg?1 at harvest. In plants raised in peat blocks containing 10 or 20 mg a.i. per block, however, residues in seedlings totalled 45-47 mg kg?1 and declined to only 0.7 mg kg?1 at harvest. It was concluded that bowwave applications of phorate when field-sowing lettuce were unlikely to lead to unacceptable residues in the harvested crop, but that residues in lettuce raised in phorate-treated peat blocks may be unacceptably high. 相似文献
96.
The case histories of thirty-five dogs with cervical spondylopathy are described with particular emphasis on diagnosis and surgical treatment, with follow-up records of both treated and untreated cases. Some evidence is presented to show that the syndrome is an inherited defect. 相似文献
97.
Stephanie C. Essman DVM John P. Hoover MS DVM Robert J. Bahr DVM Jerry W. Ritchey DVM PhD Christine Watson DVM 《Veterinary radiology & ultrasound》2002,43(3):255-259
A 7-year-old, neutered male Labrador Retriever presented for a persistent, productive cough and regurgitation. Radiography, ultrasonography, and computed tomography confirmed a large, smoothly marginated intrathoracic mass causing tracheal compression. The mass was removed via a thoracotomy, and a malignant peripheral nerve sheath tumor, most likely originating from the ventral spinal nerve roots, was confirmed using immunohistochemistry. 相似文献
98.
Sven Reese Dr Med Vet Christine Ruppert Dr Med Vet 《Veterinary radiology & ultrasound》2001,42(3):272-275
The purpose of this study was to evaluate the applicability of ultrasonographic imaging of the vagosympathetic trunk in the dog. Cervical ultrasound was performed in 30 healthy dogs. In all 30 dogs the vagosympathetic trunk was detected as a hypoechoic structure in the carotid sheath, adhering the dorsomedial surface of the common carotid artery. The echotexture of the nerve was heterogeneous with anechoic areas separated by hypoechoic bands. A scanner equipped with a 5 to 8 MHz linear array probe was used for imaging and measurements. The diameter of the vagosympathetic trunk ranged from 0.59 to 2.48 mm varying in correlation to the body weight. In summary, ultrasonography is a helpful noninvasive method to image and evaluate the cervical vagosympathetic trunk in the dog. 相似文献
99.
The use of porcine small intestinal submucosa in ten cases of feline corneal disease 总被引:3,自引:0,他引:3
Heidi J. Featherstone Jane Sansom Christine L. Heinrich† 《Veterinary ophthalmology》2001,4(2):147-153
Porcine small intestinal submucosa (SIS) was used as a novel graft material in the management of 10 cases of feline corneal disease. Five cases had stromal ulceration associated with trauma, ocular foreign body and/or suspected infection and required a grafting procedure. Five cases had feline sequestra that were managed by a keratectomy prior to placement of SIS as a graft material. Eight eyes healed with minimal corneal scarring with a very good cosmetic and visual result. One eye with continued aqueous leakage in the immediate postoperative period required a conjunctival pedicle graft to reinforce the SIS graft site. One eye required enucleation 48 h following grafting due to progressive keratomalacia but the SIS material remained intact. 相似文献
100.
Frances J. Barr MA VetMB Mark W. Patteson MA Vetmb Vanda M. Lucke BVSc PHD Christine Gibbs BVSc PHD 《Veterinary radiology & ultrasound》1989,30(4):169-173
Persistent hypercalcemia in the dog is most commonly seen as a paraneoplastic syndrome or in association with widespread osteolytic lesions. In high concentrations calcium is a potent nephrotoxin and may cause severe and irreversible renal damage. The ultrasonographic changes in the kidneys of three dogs with hypercalcernic nephropathy are described'and compared with the changes described in the same human condition. It is suggested that ultrasound could be a useful technique for evaluation of the severity of renal damage and the potential return of renal function in such instances. 相似文献