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排序方式: 共有343条查询结果,搜索用时 15 毫秒
1.
Clifford R. Berry DVM Kathy N. Wright DVM Edward B. Breitschwerdt DVM Jerome M. Feldman MD 《Veterinary radiology & ultrasound》1993,34(1):52-55
A 13-year-old neutered female Yorkshire terrier presented with a history of progressive episodic weakness and disorientation of 4 months duration. Physical and neurologic examinations were normal at presentation. Abdominal ultrasound revealed a mass involving the right adrenal gland. Standard planar scintigraphy was performed at 4, 18, and 24 hours after intravenous injection 185 MBq (5mCi) of 123 I-labeled metaiodobenzylguanidine (123 I-MIBG). An area of focal intense uptake was identified in the area of the right adrenal gland. A pheochromocytoma was confirmed histologically after surgical excision. 相似文献
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The use of plant water status indicators such as midday stem water potential (Ψstem) and maximum daily trunk shrinkage (MDS) in irrigation scheduling requires the definition of a reference or threshold value, beyond which irrigation is necessary. These reference values are generally obtained by comparing the seasonal variation of plant water status with the environmental conditions under non-limiting soil water availability. In the present study an alternative approach is presented based on the plant’s response to water deficit. A drought experiment was carried out on two apple cultivars (Malus domestica Borkh. ‘Mutsu’ and ‘Cox Orange’) in which both indicators (Ψstem and MDS) were related to several plant physiological responses. Sap flow rates, maximum net photosynthesis rates and daily radial stem growth (DRSG) (derived from continuous stem diameter variation measurements) were considered in the assessment of the approach. Depending on the chosen plant response in relationship with Ψstem or MDS, the obtained reference values varied between −1.04 and −1.46 MPa for Ψstem and between 0.17 and 0.28 mm for MDS. In both cultivars, the approach based on maximum photosynthesis rates resulted in less negative Ψstem values and smaller MDS values, compared to the approaches with sap flow and daily radial stem growth. In the well-irrigated apple trees, day-to-day variations in midday Ψstem and MDS were related to the evaporative demand. These variations were more substantial for MDS than for midday Ψstem. 相似文献
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Ponnampalam EN Sinclair AJ Egan AR Blakeley SJ Li D Leury BJ 《Journal of animal science》2001,79(4):895-903
In a previous study we showed that feeding fish meal significantly increased muscle long chain n-3 fatty acids (FA) and hot carcass weight. In this study we compared the effect of fish meal and fish oil on increasing muscle long-chain FA. We also investigated whether the increase in carcass weight was due to the effect of dietary enrichment of muscle long-chain n-3 FA on muscle membrane phospholipids and(or) to rumen by-pass protein provided by fish meal. Forty crossbred ([Merino x Border Leicester] x Poll Dorset) wether lambs between 26 and 33 kg BW were randomly assigned to one of five treatments: 1) basal diet of oaten:lucerne chaff (Basal); 2) Basal + fish meal (9% DM) = FM; 3) Basal + fish oil (1.5% DM) with protected sunflower meal (9% DM ) = FOSMP; 4) Basal + fish oil (1.5% DM) = FO; or 5) Basal + protected sunflower meal (10.5% DM) = SMP. Daily intake of ME (9.60 - 10.5 MJ ME/d) and CP (150 to 168 g/d) in all treatments was kept similar by varying the ratio of oaten:lucerne chaff and by feeding the animals at 90% ad libitum intake. Blood samples were collected at the start of the experiment and on the day (d 42) prior to slaughter. Lambs were then slaughtered at a commercial abattoir. At 24 h postmortem carcass traits were measured and longissimus thoracis muscle taken for analysis of FA of phospholipid and triglyceride fractions. Lambs fed FO and FOSMP showed a marked increase in muscle longchain n-3 FA (P < 0.001) and a reduction in magnitude of the rise in insulin concentration (P < 0.001) after feeding compared with lambs fed Basal and SMP diets. Lambs in FM had a moderate increase (P < 0.001) in muscle long-chain n-3 FA content. Compared with Basal diet, both plasma total cholesterol (P < 0.02) and high-density lipoprotein cholesterol (P < 0.001) levels were greater in SMP and less in FO and FOSMP treatments. The i.m. fat content was reduced (P < 0.05) in FM and FO treatments, but carcass weight was increased only with fish meal (P < 0.03). Adding SMP to FO produced muscle with an intermediate level of i.m. fat, whereas muscle long-chain n-3 FA, i.m. fat, and insulin concentration were unchanged with SMP treatment. These results indicate that an increase in carcass weight in FM may be due to the supply of ruminally undegraded protein. They also suggest that fish oil along with fish meal can increase long-chain n-3 FA content in phospholipid of muscle membrane. This may be associated with reduced i.m. fat content and altered insulin action and lipoprotein metabolism. 相似文献
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Kathy C. Tater DVM Sharon Drellich DVM DACVECC Kathy Beck DVM DACVR 《Journal of Veterinary Emergency and Critical Care》2005,15(1):52-59
Objective: To report a case of femoral artery thrombosis and its medical management in a young dog. Case summary: A 13‐week‐old, female Boxer puppy presented with hind limb paralysis after an abdominal crush injury. A left femoral artery thrombus was identified on ultrasound. No spinal trauma was visualized in imaging studies. Clinical management of arterial thrombosis in a 13‐week‐old puppy with streptokinase and dalteparin therapy is described. New or unique information provided: This paper describes an unusual presentation of arterial thrombosis. The medical management with streptokinase and dalteparin is also out of the ordinary. Images that document the development of compensatory circulation around the thrombosed vessel are included. Additionally, this paper also documents the altered development that occurred in this immature dog after the thrombotic event. 相似文献
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New evidence is presented to support the contention that the amoeba/cyst colonies isolated from surface-sterilized Spongospora subterranea f.sp. subterranea -infected potato tubers and spore balls have a saprophytic phase but are contaminants and not S. subterranea. Amoebae isolated from infected tissues and spore balls formed colonies associated with bacteria on 1% water agar at 18°C and encysted after 5–7 days. These cysts were morphologically distinct from the resting spores of S. subterranea and were formed singly or in a layer, unlike the spore ball (cystosorus) of S. subterranea . Amoebae, cysts and mixtures of amoebae and cysts in primary, secondary and tertiary subcultures failed to infect tomato roots. PCR amplification of DNA from amoebae, cysts and spore balls using the S. subterranea -specific primer pair SsF/R generated a 434-bp product from S. subterranea spore balls only and not from amoebae or cysts. When an amoeba/cyst-specific primer pair AmF/R was designed and used for PCR amplification, a single 411-bp product was generated from DNA of amoebae and cysts, but not from DNA of S. subterranea spore balls. These results are discussed in relation to earlier reports claiming the successful isolation of S. subterranea and other plasmodiophorids in vitro . 相似文献
8.
Parker S Campbell J McIntosh K Gajadhar A 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(9):732-734
The diagnostic test for Tritrichomonas foetus in bulls is microscopic examination of cultured preputial samples. Trichomonads other than T. foetus can be present in a preputial sample. Both a staining technique and a polymerase chain reaction assay were useful in differentiating between T. foetus and another trichomonad observed in samples from virgin bulls. 相似文献
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Cloning,expression, purification,and biological activity of five feline type I interferons 总被引:1,自引:0,他引:1
Wonderling R Powell T Baldwin S Morales T Snyder S Keiser K Hunter S Best E McDermott MJ Milhausen M 《Veterinary immunology and immunopathology》2002,89(1-2):13-27
Type I interferons (IFN) are important mediators of the host defense against viral infections in mammals. In humans multiple subtypes of IFN-alpha exist, most of which possess antiviral activity. Little is known about the type I IFN genes in cats and the role they may play in feline immunological responses to viruses. We have isolated cDNAs encoding five feline IFN-alpha (feIFN) subtypes that share from 95 to 99% amino acid sequence identity. FeIFN-alpha5 has five additional amino acids inserted at position 139, which are not present in the other four subtypes. Sequence identity of the feIFN proteins encoded by the five clones compared to human IFN-alpha2 is approximately 60%. Unlike most of the human subtypes, each of the five feline IFN sequences has an N-glycosylation recognition site. Expression of all five feIFN-alpha subtypes in Chinese hamster ovary (CHO) cells was confirmed by Western blot analysis, and all resulting proteins were glycosylated. The antiviral activity of each feIFN-alpha subtype produced in transiently transfected CHO cell cultures was tested in vitro. In addition, subtype feIFN-alpha6 was expressed in the yeast, Pichia pastoris. The resulting secreted mature recombinant protein was purified and demonstrated significant antiviral activity and induction of 2',5'-oligoadenylate synthetase activity in vitro. 相似文献