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排序方式: 共有387条查询结果,搜索用时 140 毫秒
1.
Karol A. Mathews DVM DVSc Melanie J. Brooks RVT Anne E. Valliant BSC 《Journal of Veterinary Emergency and Critical Care》1996,6(1):33-43
A one year prospective study was conducted to determine the association between intravenous catheter contamination and increased dwell time, and to identify any related risk factors. Intravenous catheters obtained from 23 cats and 98 dogs in the Intensive Care Unit at the Ontario Veterinary College with dwell times > 72 hours for the test group (n=58) and < 72 hours for a corresponding control group (n=63) were cultured between April 1991 and March 1992. One hundred and twenty one catheters were cultured, 16 jugular, 99 cephalic, and 6 saphenous. The overall contamination rate was 13 out of 121 catheters cultured (10.7%); 9/63 (14.3%) control and 4/58 (6.9%) test catheters. The bacteria isolated were E.aerogenes, S.aureus (3), P.aeruginosa, P.multocida, and Bacillus sp (7). The Bacillus sp positive catheters (5 control and 2 test) were placed during a five day period, and contaminated gauze squares were identified as the source of infection in these catheters. After these were removed from the study, the group infection rate was 6.9% control and 3.6% test. There was no significant difference between groups and no associated risk factors were identified. We conclude that intravenous dwell time need not be restricted to <72 hours. 相似文献
2.
S.K. Weldon D.A. Mosier K.R. Simons R.C. Craven A.W. Confer 《Veterinary microbiology》1994,40(3-4):283-291
To identify antigens which may be important for stimulating immunity to pneumonic pasteurellosis, a bovine antiserum to whole P. haemolytica was used to screen a recombinant lambda gt11/P. haemolytica expression library. One of the recombinant bacteriophage clones identified with the bovine antiserum, SW20C, expressed a fusion protein which was also recognized by rabbit antiserum to partially purified P. haemolytica culture supernatant and was found to be immunogenic in guinea pigs. The guinea pig antibody recognized a 100 kDa protein in P. haemolytica cell lysates. Sequence analysis of the cloned DNA from SW20C identified a fragment of 1443 bp with a small open reading frame that was contiguous with the lacZ sequence. The 153 bp P. haemolytica-specific open reading frame encoded a polypeptide of approximately 6kDa. Homology searches of Genbank and the EMBL data bases revealed no homology of this open reading frame with any other bacterial sequences including P. haemolytica leukotoxin and Ssa1. Evaluation of sera from calves that were scored either susceptible or resistant to experimental pneumonic pasteurellosis demonstrated a significant (P < 0.001) correlation between the intensity of the antibody response to the SW20C antigen and resistance to disease. 相似文献
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Melanie C. Wergin Med. Vet. Kurt Ballmer-Hofer PhD Malgorzata Roos PhD Roger E. Achermann Med. Vet. Natalie Inteeworn Med. Vet. Margarete K. Akens Med. Vet. Hans Blattmann PhD Barbara Kaser-Hotz Dr. Med. Vet. 《Veterinary radiology & ultrasound》2004,45(3):247-254
High plasma vascular endothelial growth factor (VEGF) concentrations are associated with radiation resistance and poor prognosis. After an exposure to ionizing radiation in cell culture an early phase and a late phase of increased VEGF have been documented. The activation was dependent on the radiation dose. Therefore, the purpose of this study was to measure baseline plasma VEGF and changes in VEGF over the course of fractionated radiation therapy in dogs with spontaneous tumors. Dogs with tumors had a significantly higher pretreatment plasma VEGF than did dogs without tumors. Immediately after irradiation no increased plasma VEGF was observed. Over the course of radiation therapy there was an increased plasma VEGF in dogs treated with low doses per fraction/high total dose, whereas plasma VEGF remained stable in dogs irradiated with high doses per fraction/low total dose. The regulatory mechanisms are very complex, and therefore the value of plasma VEGF measurements as an indirect marker of angiogenesis induced by radiotherapy is limited. 相似文献
5.
Carmen Klein Melanie Feist Gabriela Knubben-Schweizer Britta Dobenecker 《Journal of animal physiology and animal nutrition》2021,105(6):997-1001
High-yielding dairy cows collapsed and died displaying signs of a disturbed central nervous system (muscle tremor, convulsion) and a considerably reduced body condition score. An intense diagnostic screening did not allow to confirm a definite diagnosis. Therefore, further analyses including an evaluation of feeds and feeding were initiated. The herd was fed a total mixed ration (TMR) based on corn and grass silage of moderate nutritive value supplemented with various amounts of chocolate chips. In retrospect, the amount of chocolate chips added to the respective TMR batches could not be quantified. These chips were purchased from a company producing bakery and chocolate products for human consumption and added to the silage and therefore to the TMR in order to increase the energy intake of the animals. Because the TMR, which was fed during the time of the incidence, was no longer available, a sample of a later batch of silage was examined. The amount of chocolate chips was quantified (0.44% per fresh matter), and a theobromine analysis was performed in the chocolate chips of the available batch (69.7 mg/100 g fresh matter). Because of the possible link between chocolate intake and observed signs, an immediate cessation of using the chocolate chips was recommended in addition to an optimisation of the TMR, that is an increase of the energy density. Even though the theobromine intake during the time of the incidence is unknown and information about toxicity of theobromine in ruminants is limited, we suspect that the feeding of chocolate in this case caused all signs including the sudden death of the cows. Further reasons are that no differential diagnoses were established and the problems at the farm stopped after removing the chocolate from the TMR. 相似文献
6.
Buchholz J Wergin M Walt H Gräfe S Bley CR Kaser-Hotz B 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):770-775
BACKGROUND: Squamous cell carcinomas are common skin tumors in cats. We investigated photodynamic therapy (PDT) using a new liposomal photosensitizer as a minimally invasive, effective treatment that can be easily performed while achieving good cosmetic results. AIM: The goal of this study was to assess and describe possible toxicities using a liposomal formulation of the photosensitizer meta-(Tetrahydroxyphenyl)Chlorin (m-THPC) and investigate if favorable pharmacokinetics translate into favorable tumor response and control. ANIMALS: Eighteen client-owned cats with 20 spontaneous cutaneous squamous cell carcinomas were included in the study. METHODS: PDT was performed using a new, liposomal formulation of the photosensitizer. Toxicity, tumor response, and tumor control were evaluated retrospectively. RESULTS: No general adverse effects were observed in cats treated with the new liposomal formulation. Mild local toxicity such as erythema and edema were seen in 15% of the patients. All cats responded to therapy, with a complete response rate of 100%. The overall 1-year control rate was 75%. The tumor recurrence rate was 20% with a median time to recurrence of 172.25 +/-87.1) days. CONCLUSIONS AND CLINICAL IMPORTANCE: A new liposomal photosensitizer was successfully used for squamous cell carcinoma in cats and was well tolerated. There were no systemic adverse effects observed with the liposomal formulation. The favorable pharmacokinetics of the liposomal drug resulted in a favorable tumor response. 相似文献
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8.
Melanie Schmitt Andreas Turberg Michael Londershausen August Dorn 《Pest management science》1996,48(4):375-388
The calcium channel and the ‘calcium release channel’ of muscle membrane of the cockroach Periplaneta americana have been characterized. Biological assays with calcium channel blockers and ryanodine on different insects and acari revealed pronounced insecticidal effects with ryanodine, but not with calcium channel blockers, at concentrations between 0·1 and 300 μg ml−1. Skeletal muscle membranes derived either from the tubular network or from the sarcoplasmatic reticulum of P. americana were characterized with respect to the binding of the dihydropyridine (DHP) [3H]isradipine (PN 200-110), the phenyl-alkylamine [3H]verapamil and the alkaloid [3H]ryanodine. Preliminary binding studies with the benzothiazepine [3H]diltiazem suggest a low-affinity binding site with a IC50 value of 3·3 μM . All binding sites tested were sensitive to treatment with proteinase K. Optimal conditions for binding of the radioligand ryanodine revealed the highest specific binding at pH 8 and at calcium chloride concentrations between 100 and 500 μM . EGTA at 10 μM abolished 95% of the ryanodine binding. Binding studies with calcium channel binding sites revealed a pronounced effect of low Ca2+ concentrations on specific isradipine binding, whereas verapamil and diltiazem binding were only reduced by the presence of 200 μM EGTA. With respect to high Ca2+ concentrations, specific binding of diltiazem, isradipine and verapamil was reduced by 73, 40 and 20%, respectively, at 5 mM Ca2+. Radioligand binding experiments showed high-affinity binding sites for ryanodine and isradipine. KD values of 0·95 nM (Bmax=550 fmol mg−1 protein) and 0·75 nM (Bmax=213 fmol mg−1 protein) were determined respectively. A lower-affinity binding site was identified in binding studies with verapamil (KD=7·4 nM and Bmax=27 fmol mg−1 protein). [3H]isradipine displacement studies with several dihydropyridines revealed the following ranking of affinity: nitrendipine>isradipine>Bay K8664≪nicardipine. Displacement of [3H]verapamil binding by effectors of the phenylalkylamine binding site showed that bepridil and S(-)verapamil had the highest affinities of the compounds tested followed by (±)verapamil, nor-methylverapamil and R(+)verapamil. 相似文献
9.
Substitution of fish meal (FM) as a protein source in aquaculture diets is required to reduce cost and promote a sustainable industry. Potential protein sources include a range of traditional products from agricultural production such as plant or animal proteins. However, there are also a number of manufacturing coproducts, including bacterial dried fermented biomass (DFB,) for which there is an increased interest. Hence, the objective of this study was to evaluate DFB as a replacement for FM in practical diets for Florida pompano, Trachinotus carolinus. Four diets were prepared in which different levels of FM (15%, 10%, 5%, and 0% of the diet) were replaced with DFB (0%, 4.27%, 8.54%, and 12.82%) on an iso-nitrogenous and iso-lipidic basis, to contain 40% crude protein and 10% lipid. A 10-week growth trial was conducted in a recirculating system consisting of 12 indoor 1.0 m3 tanks, stocked with 20 juvenile pompano (mean initial weight 8.1 g) per tank. There were no significant differences in final weight (64.5 g?79.5 g), survival (81.7%–96.7%), percent weight gain (711.6%–879.0%), FCR (2.1–2.0), or thermal-unit growth coefficient (0.1013?0.1149), regardless of the levels of dietary FM or DFB tested. Based on these results, it is recommended that DFB can be included up to 12.8% in practical diets for Florida pompano without significantly reducing growth performance. The response to higher levels of DFB inclusion should be evaluated. 相似文献
10.