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561.
562.
J. Jiang L. Feng Y. Liu W.‐D. Jiang K. Hu S.‐H. Li X.‐Q. Zhou 《Aquaculture Nutrition》2014,20(6):731-740
Glutaminase (GLS) is the key enzyme of glutamine (Gln) metabolism and utilization. In this study, a cDNA encoding GLS protein was identified from common carp Cyprinus carpio intestine. The open reading frame of GLS cDNA encodes a polypeptide of 595 amino acids, which shows a high similarity with its zebrafish Danio rerio counterpart. Bioinformatic analysis showed the protein belongs to kidney‐type GLS. The putative protein has glutaminase domain and ankyrin repeats domain, which are highly conserved among vertebrate orthologues. Real‐time quantitative PCR analysis revealed that the abundance of GLS mRNA was the highest in the white muscle, followed by the brain, eyeball and pituitary. Glutaminase was ubiquitously expressed in all intestinal segments of common carp. The activity of GLS did not distribute uniformly along the entire length of the intestine. In primary culture enterocyte, and the expression of GLS mRNA is up‐regulated quickly and effectively by Gln. 相似文献
563.
K. E. O'Neill M. A. Labato M. H. Court 《Journal of veterinary pharmacology and therapeutics》2016,39(2):202-204
Fenoldopam is a selective dopamine‐1 receptor agonist that improves diuresis by increasing renal blood flow and perfusion and causing peripheral vasodilation. Fenoldopam has been shown to induce diuresis and be well‐tolerated in healthy cats. It is used clinically in cats with oliguric kidney injury at doses extrapolated from human medicine and canine studies. The pharmacokinetics in healthy beagle dogs has been reported; however, pharmacokinetic data in cats are lacking. The goal of this study was to determine pharmacokinetic data for healthy, awake cats receiving an infusion of fenoldopam. Six healthy, awake, client‐owned cats aged 2–6 years old received a 120‐min constant rate infusion of fenoldopam at 0.8 μg/kg/min followed by a 20‐min washout period. Ascorbate stabilized plasma samples were collected during and after the infusion for the measurement of fenoldopam concentration by HPLC with mass spectrometry detection. This study showed that the geometric mean of the volume of distribution, clearance, and half‐life (198 mL/kg, 46 mL/kg/min, and 3.0 mins) is similar to pharmacokinetic parameters for humans. No adverse events were noted. Fenoldopam at a constant rate infusion of 0.8 μg/kg per min was well tolerated in healthy cats. Based on the results, further evaluation of fenoldopam in cats with kidney disease is recommended. 相似文献
564.
Assessment of defined antigens for the diagnosis of bovine tuberculosis in skin test-reactor cattle 总被引:17,自引:0,他引:17
Pollock JM Girvin RM Lightbody KA Clements RA Neill SD Buddle BM Andersen P 《The Veterinary record》2000,146(23):659-665
The continued use of purified protein derivative (PPD) tuberculin is considered to be the main factor which limits the specificity of diagnostic tests for bovine tuberculosis (TB). This study evaluated a whole blood interferon-gamma (IFN-gamma) assay and compared the diagnostic potential of PPD with two tuberculosis-specific antigens, ESAT-6 and MPB70. To provide estimates of sensitivity and specificity, responses were measured in 180 skin test-reacting cattle, of which 131 were confirmed as tuberculous, and in 128 cattle from TB-free herds. For the skin test reactors, there was a positive correlation between the IFN-gamma responses to PPD from Mycobacterium bovis (PPDB) and PPD from Mycobacterium avium (PPDA), indicating cross-reactivity between these complex antigens which are the basis of the skin test. In comparisons of the ESAT-6 IFN-gamma test with a PPD IFN-gamma test (using PPDB compared with PPDA), there was a decrease in sensitivity (76.3 per cent vs 89.3 per cent), but a clear increase in specificity (99.2 per cent vs 92.2 per cent). The provision of high specificity, even with lower sensitivity, offers major benefits for testing in areas with a low incidence of TB. 相似文献
565.
Strip loins from two experiments were used to evaluate effects of feeding dry (DDG) or wet (WDG) distiller's grains on beef color, tenderness, and sensory traits of Holstein steers. In Exp. 1, conducted at the University of Illinois at Champaign-Urbana, dietary treatments consisted of a control whole corn-corn silage diet with soybean meal (SBM) or diets formulated with 12.5% DDG plus urea, 25% DDG, 25% WDG, 50% DDG, or 50% WDG (DM basis). In Exp. 2, conducted at Iowa State University, dietary treatments consisted of cracked corn-corn silage-hay diets with either SBM or urea (Urea) as the control diets, or diets formulated with 10, 20, or 40% DDG or WDG (DM basis). Within each study, strip loins from each of four steers (representing 45.7 and 66.6% of steers in Exp. 1 and 2, respectively) in four replicate pens per treatment were aged for 13 d at 4 degrees C for subsequent color, tenderness, and palatability evaluation. Color of steaks was measured objectively using a HunterLab Miniscan XE spectrophotometer and was subjectively evaluated by a trained panel. Tenderness was measured using the Warner-Bratzler shear force (WBSF) instrument on steaks cooked to 70 degrees C. For sensory evaluation, 95 consumers were recruited to evaluate tenderness, juiciness, and flavor of cooked steaks. In Exp. 1, steaks from steers fed 25% WDG had higher (P < 0.05) a* values after 138 h of simulated retail display than all other treatments, except for those from steers fed 12.5% DDG. In Exp. 2, a greater (P < 0.05) percentage of steaks from steers fed 40% DDG or 40% WDG were considered moderately undesirable during retail display (steaks that received a consumer acceptability score of 3 or less). There were no (P = 0.20 in Exp. 1, and P = 0.33 in Exp. 2) differences among treatments in Exp. 1 and Exp. 2 for WBSF (1.47 +/- 0.66 kg and 1.58 +/- 0.72 kg, respectively) or taste panel tenderness (5.7 +/- 0.30 and 6.2 +/- 0.22, respectively), beef flavor (6.0 +/- 0.23 and 6.2 +/- 0.22, respectively), and juiciness (5.6 +/- 0.31 and 5.8 +/- 0.23). Feeding distiller's grains at up to 50% of the dietary DM did not affect tenderness or sensory traits, and seems to be a viable feed alternative without negatively impacting sensory attributes. 相似文献
566.
567.
N. BHARATHAN W. R. GRAVES K. R. NARAYANAN D. J. SCHUSTER† H. H. BRYAN R. T. McMILLAN JR 《Plant pathology》1990,39(3):530-538
A disorder of unknown aetiology appearing as silvering on squash (Cucurbita pepo) leaves has become prevalent in south Florida. Typical symptoms, observed after 2 weeks of exposure to adults of Bemisia tabaci , the sweet potato whitefly (SPWF) include vein clearing followed by silvering of whole leaves. Fruits from affected plants are blanched or streaked longitudinally. The silverleaf syndrome was not mechanically transmissible when crude extracts of symptomatic leaves were used as inoculum. Two sizes of double-stranded RNA (dsRNA) of c. 4.6 and 4.2 kilobase pairs (kbp) were consistently observed in leaf extracts of caged, whitefly-infested, symptomatic plants. In contrast, caged plants not exposed to whiteflies showed no symptoms and contained no detectable dsRN A. In addition, squash plants exposed to SPWF colonies from California neither developed silverleaf symptoms nor contained any dsRNA. Double-stranded RNA could also be readily detected in whitefly-infested yellow summer squash and zucchini from the field. However, asymptomatic eggplant and watermelon infested with SPWF from nearby fields did not contain detectable dsRNA. Dot-spot hybridization assays using an RNA-specific probe detected homologous sequences in both adults and nymphs of SPWF that induced silverleaf symptoms but not in adults and nymphs of SPWF that could not induce silverleaf symptoms. These results, along with the non-endogenous nature of the detected dsRNA suggest that the dsRNA is or is associated with the causal agent of whitefly-mediated leaf silvering in squash. 相似文献
568.
Autochthonous Chagas disease in the southern United States: A case report of suspected residential and military exposures 下载免费PDF全文
N. Harris L. Woc‐Colburn S. M. Gunter R. Gorchakov K. O. Murray S. Rossmann M. N. Garcia 《Zoonoses and public health》2017,64(6):491-493
Chagas disease is a parasitic infection that can result in a progressive dilated cardiomyopathy. Here, we present the epidemiologic details of a suspected locally acquired transmission case originating from the southern United States. This is the first published report of Chagas disease in a young, healthy United States veteran with repeat triatomine exposures in Arizona. Military personnel and Arizona residents should be aware of their Chagas disease transmission risks. 相似文献
569.
Three experiments were conducted to test the hypothesis that different starter feeding programs (High, high quality; Low, low quality) will affect growth performance and body composition of pigs from weaning to market weight and that this effect may be influenced by gender (barrows or gilts) and breed (F, Yorkshire-Duroc x Hampshire; P, PIC Camborough 15 x PIC line 405). In Exp. 1, 21 +/- 4-d-weaned F pigs (n = 90) were used in a 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 2, 21 +/- 3-d-weaned pigs (n = 184) were used in a 2 (F or P) x 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 3, 21 F pigs from each gender and feeding program treatment were killed at d 0, 3, 7, 14, 42, 82, or 152 postweaning for evaluating body composition. Two starter feeding programs (High or Low) were applied to pigs for 6 wk postweaning. Pigs from both High and Low treatments were provided the same corn-soybean meal-based diets for the growing and finishing periods. Although the ADG of all pigs receiving the High treatment during the early starter period were higher (P < .01) than those of the Low, the terminal BW of F barrows were similar between High and Low (Exp. 1 and 2) and those of gilts were similar between High and Low (Exp. 2) (P > .80). However, the BW of P pigs receiving the High treatment, regardless of gender, tended to be heavier than those receiving the Low (Exp. 2) and F barrows receiving the High treatment tended to be heavier than those receiving the Low (Exp. 1). For the first 7 d postweaning, the High-fed pigs gained more protein (P < .05) and lost less fat (P < .05) than Low-fed pigs. During the growing-finishing period, the Low-fed pigs exhibited compensatory protein gain and achieved a body protein content similar (P < .60) to High-fed pigs by termination. Protein gains from weaning to termination between High- and Low-fed pigs were not different in Exp. 2 and 3. The protein gain of gilts was higher (P < .05) than that of barrows. Similarly, fat gain within genders was not affected by starter feeding program. Fat gain of gilts, however, was lower (P < .08) than that of barrows in Exp. 3. In conclusion, the nutritional quality of the starter feeding program affected growth performance immediately after weaning but did not affect protein gain over the entire production period. 相似文献
570.
Radiodiagnostic methods have not been used previously for studying the anatomy and diseases of the swimbladder of freshwater fish species. In this study, the radiographic anatomy of the swimbladder and species-related differences in swimbladder structure were studied on plain radiographs taken of 12 Hungarian fish species of major economic importance. Changes observed by radiography were also studied by conventional parasitological methods. The radiodiagnostic method reported here appears to be a useful complement to diagnostic examinations that have been based merely on dissection so far. It enables evaluation of the pathological lesions in live condition, without causing damage to the fish. 相似文献