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981.
A comparative randomized crossover study was conducted to determine the pharmacokinetics of theophylline in male and female camels (Camelus dromedarius) and goats (Caprus hircus). Theophylline is an established 'probe drug' to evaluate the drug metabolizing enzyme activity of animals. It was administered by the intravenous (i.v.) route and then intramuscularly (i.m.) at a dose of 2 mg/kg. The concentration of the drug in plasma was measured using a high-performance liquid chromatography (HPLC) technique on samples collected at frequent intervals after administration. Following i.v. injection, the overall elimination rate constant (lambda z,) in goats was 0.006 +/- 0.00076/min and in camels was 0.0046 +/- 0.0008/min (P < 0.01). The elimination half-life (t 1/2 lambda z) in goats (112 .7 min) was lower than in camels (154.7 min) (P < 0.01). The apparent volume of distribution (Vz) and the total body clearance (Cl) in goats were 1440.1 +/- 166.6 ml/kg and 8.9 +/- 1.4 ml/min/kg, respectively. The corresponding values in camels were 1720.3 +/- 345.3 ml/kg and 6.1 +/- 1.0 ml/min/kg, respectively. After i.m. administration, theophylline reached a peak plasma concentration (Cmax) of 1.8 +/- 0.1 and 1.7 +/- 0.2 microg/ml at a post-injection time (Tmax) of 67.5 +/- 8.6 and 122.3 +/- 6.7 min in goats and camels, respectively. The mean bioavailability (T) in both goats and camels was 0.9 +/- 0.2. The above data suggest that camels eliminate theophylline at a slower rate than goats.  相似文献   
982.
疫苗是一类需要给予精心管理的敏感产品,将其置于适当的温度下进行保存和运输极为重要.热应激可能会降低疫苗的效价,或甚至会使其失去活性,目前的疫苗热稳定剂功效如何呢?  相似文献   
983.
Our objective was to evaluate kidney antioxidant status in rats subjected to an ultrasound examination. Thirty rats were divided into five groups for injection of saline (S) or anesthetic (A), and application of ultrasound using different modes, B mode, pulsed wave Doppler, and continuous wave Doppler, under anesthesia. Ultrasound was performed on days 1, 3, and 5 relative to the initiation of the experiment. Rats were then scarified on day 6. The kidney tissue thiobarbituric acid reactive substance (TBARS) level and superoxide dismutase (SOD) activity were measured. Both TBARS level and SOD activity increased, 21% and 38%, respectively, due to anesthesia (P < 0.04 for both). SOD activity increased further by a factor of 1.2 in response to ultrasound examination (P < 0.05), whereas TBARS level was not affected by Doppler and continuous wave Doppler compared to anesthesia. Increases in the level of TBARS (P < 0.03) and SOD activity (P < 0.01) were greatest when B-mode ultrasound was employed. These substances did not increase further when continuous wave Doppler was employed. The peak-negative acoustic pressure (9.16 vs. 9.74 MPa) and frequency (3.57 vs. 6.95 MHz) for B mode and pulsed wave Doppler were greater than those for continuous wave Doppler (0.22 MPa and 1.96 MHz). The estimated mechanical indexes were 4.87, 3.70, and 0.15 for B mode, pulsed wave Doppler, and continuous wave Doppler, respectively. In conclusion, anesthesia may cause tissue damage as reflected by elevated lipid peroxidation and free radical formation and ultrasound examination may amplify tissue damage through mechanical effects caused by ultrasound absorption.  相似文献   
984.
985.
Staphylococcus aureus is a commensal and pathogenic bacterium with impact on public health and livestock industry. The study investigated nasal carriage, antibiotic resistance, and molecular characterization of S. aureus in pigs and pig workers. Nasal swabs from 300 backyard-raised pigs and 101 pig workers were used for the study. Resulting isolates were confirmed using MALDI-TOF MS, tested for antibiotic resistance, and three different multiplex PCRs were used to detect enterotoxin, mecA, spaA, scn, and pvl genes. spa typing was used to annotate the isolates into MLST clonal complexes (CC). Structured questionnaire was used to access possible risk factors for S. aureus carriage. The prevalence of S. aureus in pigs and pig workers were 5.3 and 12.9%, respectively. The isolates were resistant to beta-lactams (97%), tetracycline (62%), sulfonamide (52%), aminoglycoside (20.6%), fluoroquinolone (24%), and mupirocin (3.4%). Twenty seven (93%) of the isolates carried scn, 7(24%) pvl, and 12 (41%) enterotoxin genes, respectively. Questionnaire survey showed medical-related occupation of household members was associated (p?<?0.5) with S. aureus carriage. This study suggests the presence of human multidrug resistant strains of S. aureus, high carriage of pvl, and enterotoxin genes, and CC5, CC15, and CC152 were the CC-groups shared among pigs and pig workers.  相似文献   
986.
BACKGROUND: Little information exists on the hypothalamic-pituitary-adrenal axis in septic foals. HYPOTHESIS: The plasma concentrations of adrenocorticotropin (ACTH) and cortisol are expected to be higher in septic foals as compared to normal foals. The concentrations of hormones in septic foals also are expected to differ further depending upon survival. ANIMALS: Twenty-eight control foals and 46 septic foals <14 days of age were included in this study. METHODS: Blood was collected in EDTA once from 28 normal foals born in the University of Georgia or Cornell University equine research herds and from 46 septic foals within 12 hours after admission to 1 of the 3 tertiary care referral centers involved in the study. Septic foal selection was based on a sepsis score of >11 or a positive blood culture. The control foals were age matched to the septic foals in the study. ACTH and cortisol concentrations were measured by a chemiluminescent immunoassay system. RESULTS: Cortisol concentrations in control foals did not vary with age. Septic foals had significantly higher mean ACTH, cortisol, and ACTH/cortisol ratios than did normal foals. Within the septic foal group, 28 foals survived to discharge, and 18 were euthanized or died. The mean age was not significantly different between the septic surviving and nonsurviving foals. The mean ACTH/cortisol ratio was significantly higher in the septic nonsurviving foals as compared to the septic surviving foals. CONCLUSIONS AND CLINICAL IMPORTANCE: Septic foals had higher hormone concentrations as compared to normal foals, which is an expected endocrine response to critical illness. The increased ACTH/cortisol ratio in nonsurviving septic foals in comparison to surviving septic foals could indicate hypothalamic-pituitary-adrenal axis dysfunction at the level of the adrenal gland in critically ill septic foals.  相似文献   
987.
Current literature on restorative environments generally shows the importance of urban natural landscapes in increasing perceived restorativeness of urban environments. However, little is known about the positive role of visual characteristics of urban natural landscapes in increasing Perceived Restorative Potential (PRP) of urban environments. This study aimed to understand the role of four predictors of visual preference as characteristics of urban natural landscape on the restorativeness of environments. In this study, 120 students from Universiti Putra Malaysia rated 12 colored slides of urban natural landscape scenes for four restorative components (Being away, Fascination, Coherence, and Compatibility), four predictors of visual landscape preference (Coherence, Complexity, Legibility, Mystery) and a criterion variable (PRP). Coherence, however, was considered as a predictor of visual landscape preference since it is not a significant predictor in explaining PRP. Results indicate that Coherence, Complexity, and Mystery positively explained PRP while Legibility did not. Further analysis revealed that the effect of Coherence and Complexity on PRP was fully mediated by the restorative components and Mystery was only partially mediated. The findings indicate that some predictors of visual landscape preference of urban natural landscapes contribute to increasing PRP of urban landscapes. Although Coherence as a restorative component was not a significant predictor of PRP, it contributed toward increasing the restorative potential of urban natural landscapes when considered as a predictor of visual landscape preference. The results of this study can aid city planners, landscape architects and developers with regards to the influence of visual landscape characteristics in increasing the restorative potential of urban environments.  相似文献   
988.
The cryoprotective effects of trehalose on fish myofibrillar protein were compared with those of sucrose, glucose and sorbitol. The frozen surimi with trehalose exhibited significantly higher Ca2+-ATPase activity through-out the storage periods, resulting in higher gel-forming ability than that of without trehalose. The amount of unfrozen water was significantly increased in the surimi upon addition of trehalose at any concentrations tested. The findings suggest that trehalose constructed bound water molecules in protein structure, consequently suppressed freeze-induced denaturation of protein and maintained gel-forming ability. An addition of 5.0% to 7.5% concentration of trehalose showed threshold behavior to increase the amount of unfrozen water and to prevent freeze-induced denaturation of protein. The effects of trehalose were almost similar to those of other sugars.  相似文献   
989.
This study was motivated by the need to find a solution to poor egg quality and the resulting mass mortality of hatchery-produced larvae of the tiger prawn, Penaeus monodon. The approach adopted sought to improve the broodstock condition and determine its effect on egg quality using rates of fertilization, hatching and metamorphosis. Broodstock specimens were given four separate dietary treatments (D1–D4), all of which comprised squid and trash fish plus supplements. D2, D3 and D4 were supplemented with bloodworm, bioencapsulated bloodworm and a commercial broodstock diet, respectively. Tricalcic phosphate (Ca3(PO4)2) was used to enrich the live bloodworm. The bioencapsulated ration performed better than regular bloodworm and other diets. This was evident from the bioencapsulation results which showed the highest rate of hatching, survival of nauplii and larvae metamorphosing into zoea stage.  相似文献   
990.
Abstract:   The total lipid content and fatty acid composition were determined in the flesh and skin of wild and cultured rainbow trout in Turkey. The effect of diet content was also investigated on cultured trout. Gas chromatography-mass spectrometry (GC-MS) was used for fatty acid analyses. Total lipid content of skin was higher than flesh in both types and when compared appreciably higher in cultured fish. The predominant fatty acid was palmitic acid (C16:0) in saturated fatty acids and oleic acid (C18:1n-9) in monounsaturated fatty acids. The amount of eicosapentaenoic acid was double in wild and docosahexaenoic acid (DHA) 1.5 times higher in cultured fish flesh. The n-3/n-6 ratio was higher in cultured fish than wild fish. The levels of palmitic, oleic, linoleic (C18:2n-6) and palmitoleic (C16:1n-7) acids were high in skin. The level of EPA was the same in skin of wild fish but 5.5 times higher in cultured fish, whereas the proportion of DHA in skin was lower for wild and 3.5 times higher in cultured fish. Wild fish had a high level of linoleic, arachidonic (C20:4n-6) and linolenic (C18:3n-3) acids. The total amount of n-3 and n-6 polyunsaturated fatty acids was higher in flesh of wild fish than cultured fish, contrary to skin of cultured fish. The data obtained demonstrated that fatty acid composition of cultured fish did not depend on that of feed.  相似文献   
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