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排序方式: 共有894条查询结果,搜索用时 15 毫秒
1.
Dominique G. Penninck DVM Antony S. Moore BVSc MVSc Amy S. Tidwell DVM Michael E. Matz DVM Greg O. Freden DVM 《Veterinary radiology & ultrasound》1994,35(4):299-306
Clinical, radiological and ultrasonographic findings from 22 cats with gastrointestinal lymphosarcoma were reviewed. The most common clinical findings were anorexia, weight loss, vomiting, lethargy, depression, fever, anemia and a palpable abdominal mass. Abdominal radiographs of 12 cats revealed a mass associated with the gastrointestinal tract and/or mesentery, and decreased serosal detail, suggestive of peritoneal effusion. The most common ultrasonographic finding was transmural gastric or intestinal thickening associated with loss of normal wall layering, reduced wall echogenicity and localized hypomotility. As is noted in people, other patterns such as transmural-segmental, transmural-nodular, transmural-bulky and mucosal infiltration were represented. In 3 cats, mesenteric lymph-adenopathy was responsible for most of the mass-effect. Fine-needle aspiration biopsy, automated microcore biopsy, endoscopic biopsy or necropsy confirmed the diagnosis of lymphosarcoma in all cats. Chemotherapy was instituted in 19 cats. Only 6 cats had a complete response to treatment. The results of this study indicate that ultrasonography is a valuable tool for the diagnosis of feline alimentary lymphosarcoma and that biopsies can be obtained under ultrasonographic guidance. 相似文献
2.
Amy M Grooters Joseph Taboada 《Veterinary Clinics of North America: Small Animal Practice》2003,33(4):749-58, vi
Fungal pathogens are becoming increasingly important for human and small animal medicine. This article highlights many standards-of-care and new agents for treatment of these pathogens for small animals and people. 相似文献
3.
Amy Wells Karen A Terio Michael H Ziccardi Linda Munson 《Journal of zoo and wildlife medicine》2004,35(1):8-14
The captive North American cheetah (Acinonyx jubatus) population is not self-sustaining because of high prevalences of unusual diseases and poor reproductive success. Cheetahs are commonly moved between zoos for breeding purposes to maintain genetic diversity within the captive population, and movement may exacerbate infertility and disease. Fecal corticoids were analyzed by radioimmunoassay to measure the stress response of cheetahs to movement between facilities. Fecal samples were collected from 15 cheetahs for 14 days before movement and for at least 30 days after movement. For each cheetah, premovement fecal corticoid concentrations were used to determine baseline and then compared with trends in postmovement concentrations. In general, postmovement corticoid concentrations either increased (n = 8), did not change (n = 2), or decreased (n = 5). Although individual animal differences occurred, corticoid concentrations increased for most animals moved on-exhibit and decreased in animals moved off-exhibit. Animals moving on-exhibit had an 18-times greater risk of having corticoids elevated more than two standard deviations above baseline for 30 days after movement compared with animals that moved off-exhibit. In addition, greater day-to-day variation in corticoids occurred in animals moved on-exhibit. In general, animals with initially low baseline corticoid concentrations had a greater postmovement corticoid response than cheetahs with initially high baseline levels. These results indicate that some cheetahs have a prolonged stress response when moved between facilities, and the magnitude and character of this response is influenced by the exhibit environment. 相似文献
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Amy M. Treonis Roger Cook Lorna Dawson Susan J. Grayston Tony Mizen 《Biology and Fertility of Soils》2007,43(5):541-548
We studied the effects of the root endoparasitic nematode Heterodera trifolii on rhizodeposition and the root architecture of white clover (Trifolium repens). Rhizosphere solutions were collected from the root systems of plants growing with and without H. trifolii (200 juveniles per inoculated plant) in sand-based microlysimeters. The organic carbon (C) content of these solutions was
analyzed, and they were applied to plant-free soils to investigate microbial responses. Although plant biomass was unaffected
by nematodes, the architecture of the root systems was significantly altered, with a decrease in overall root length and an
increase in the density of lateral branches from the primary root. The presence of nematodes reduced the concentration of
organic compounds in the rhizosphere solutions but only on the final sampling date (75 days). Analysis of microbial signature
phospholipid fatty acids revealed no change in the structure of the microbial communities in soils to which rhizosphere solutions
were applied. However, these microorganisms did respond with changes in substrate utilization patterns (community-level physiological
profiles). Microbes in soils that received rhizosphere solutions from the nematode-infected clover showed lower utilization
of most substrates but higher utilization of oligosugars. These responses appear to be related to changes in roots and rhizodeposition
associated with nematode infection of clover roots. The results of this study suggest that root herbivory can negatively impact
carbon-limited soil microbial communities via changes in root architecture that moderate rhizodeposition. 相似文献
7.
Kapatkin AS Gregor TP Hearon K Richardson RW McKelvie PJ Fordyce HH Smith GK 《Journal of the American Veterinary Medical Association》2004,224(4):542-546
OBJECTIVE: To evaluate hip joint laxity in 10 breeds of dogs via 2 radiographic techniques. ANIMALS: 500 clinically normal dogs. DESIGN: Prospective study. PROCEDURE: Radiographs obtained via routine hip joint evaluations performed in sedated dogs of 10 popular breeds were randomly selected from a database. Measurements of distraction index (DI) and hip-extended index (HEI) on 1 hip joint radiograph randomly chosen from each dog were made. RESULTS: Mean age of dogs was 20.7 months. Mean HEI was 0.17 (range, 0.0 to 0.72) and mean DI was 0.44 (range, 0.07 to 0.96). Borzois had uniformly tight hip joints as judged by use of both methods and were considered the gold standard by which hip joint laxity was judged (all Borzois had DI < or = 0.32). Overall, DI was significantly greater than HEI. Within each breed, mean DI was always greater than mean HEI. Significant differences were detected among breeds for HEI; however, compared with DI, the magnitude of differences among breeds was less. CONCLUSIONS AND CLINICAL RELEVANCE: Distraction radiography detected the greatest range and magnitude of passive hip laxity in the 10 breeds of dogs. The difference in values between breeds known to have high prevalence of canine hip dysplasia and those in Borzois was greater for DI than for HEI. Breeds must be evaluated individually because of inherent differences in hip joint laxity. 相似文献
8.
Paul E. Kendra Amy L. Roda Wayne S. Montgomery Elena Q. Schnell Jerome Niogret Nancy D. Epsky Robert R. Heath 《Postharvest Biology and Technology》2011,59(2):143-149
Tephritid fruit flies are serious economic pests worldwide. As larvae, they feed and develop within the pulp of host fruits, making infestation difficult to detect by visual inspection. At U.S. ports of entry, incoming produce shipments are checked for infestation by manually cutting open a small sample of fruit and searching for tephritid larvae. Consequently, there is a need for more sensitive, high-throughput screening methods. This study evaluated gas chromatography (GC) as a potential technology for improved detection of hidden infestation. Grapefruits (Citrus × paradisi Macfad.) infested with immature stages of the Caribbean fruit fly Anastrepha suspensa (Loew) (Diptera: Tephritidae) were examined to determine if infested fruit emitted a chemical profile distinct from that of non-infested fruit. Peaks identified by GC analysis were grouped into three classes. Chemicals detected in similar quantities in all samples, or slightly elevated in infested samples, were regarded as non-diagnostic background volatiles. Chemicals highly elevated after oviposition, during the last instar exit stage, and in experimentally-pierced fruit were interpreted to be indicators of citrus peel injury, and included d-limonene and β-ocimene. Chemicals elevated exclusively in the larval infestation stages were considered indicators of feeding damage and potentially diagnostic of infestation, and included hexyl butanoate and an unidentified compound. The peaks associated with injury and feeding were also detectable with a portable ultra-fast GC analyzer that required less than 80 s per sample. Further studies will investigate the potential application of these results for development of a rapid, non-destructive screening method for detection of tephritid infestation. 相似文献
9.
Georgios Kallifatidis Dominic Hoepfner Tiphaine Jaeg Esther A. Guzmán Amy E. Wright 《Marine drugs》2013,11(9):3500-3516
Manzamine A, a member of the manzamine alkaloids, was originally isolated from marine sponges of the genus Haliclona. It was recently shown to have activity against pancreatic cancer cells, but the precise mechanism of action remained unclear. To further our understanding of the mechanism of action of manzamine A, chemogenomic profiling in the yeast S. cerevisiae was performed, suggesting that manzamine A is an uncoupler of vacuolar ATPases. Fluorescence microscopy confirmed this effect on yeast vacuoles, where manzamine A produced a phenotype very similar to that of the established v-ATPase inhibitor bafilomycin A1. In pancreatic cancer cells, 10 µM manzamine A affected vacuolar ATPase activity and significantly increased the level of autophagosome marker LC3-II and p62/SQSTM1 as observed by western blot analysis. Treatment with manzamine A in combination with bafilomycin A1 (inhibitor of autophagosome-lysosome fusion) did not change the levels of LC3-II when compared to cells treated with bafilomycin A1 alone, suggesting that manzamine A is a potential inhibitor of autophagy by preventing autophagosome turnover. As autophagy is essential for pancreatic tumor growth, blocking this pathway with manzamine A suggests a promising strategy for the treatment of pancreatic cancer. 相似文献
10.
Songita SONOWAL Amy R. NAVA Sanket J. JOSHI Siddhartha Narayan BORAH Nazim F. ISLAM Soumya PANDIT Ram PRASAD Hemen SARMA 《土壤圈》2022,32(1):198-210
Biosurfactants are biomolecules produced by microorganisms, low in toxicity, biodegradable, and relatively easy to synthesize using renewable waste substrates. Biosurfactants are of great importance with a wide and versatile range of applications, including the bioremediation of contaminated sites. Plants may accumulate soil potentially toxic elements(PTEs), and the accumulation efficacy may be further enhanced by the biosurfactants produced by rhizospheric microorganisms. Occasionally, the growth of bacteria slows down in adverse conditions, such as highly contaminated soils with PTEs. In this context,the plant's phytoextraction capacity could be improved by the addition of metal-tolerant bacteria that produce biosurfactants. Several sources, categories,and bioavailability of PTEs in soil are reported in this article, with the focus on the cost-effective and sustainable soil remediation technologies, where biosurfactants are used as a remediation method. How rhizobacterial biosurfactants can improve PTE recovery capabilities of plants is discussed, and the molecular mechanisms in bacterial genomes that support the production of important biosurfactants are listed. The status and cost of commercial biosurfactant production in the international market are also presented. 相似文献