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1.
Using a crossover study design, the pharmacokinetics of carfentanil and naltrexone after i.v., i.m., and s.c. administration were determined in eight domestic goats (Capra hircus). Serial blood samples were taken up to 120 hr after carfentanil administration, and the plasma drug concentrations were determined using liquid chromatography and mass spectroscopy. All goats were immobilized with 40 microg/kg carfentanil i.m., although the resulting neurologic effects varied considerably. Plasma profiles showed rapid carfentanil absorption and a simple biphasic decline for 12-48 hr. Naltrexone given at 100 mg naltrexone/mg carfentanil 30 min after carfentanil administration produced rapid reversal of immobilization after all routes of administration. Variable fluctuations in the naltrexone plasma concentrations during the first 2.5-3.5 hr were observed, followed by a more consistent biphasic decline. The time to standing was significantly shorter after i.v. compared with s.c. naltrexone, although the time difference (1 min) had little clinical relevance. No statistically significant differences between the naltrexone pharmacokinetic parameters measured for the three routes of naltrexone administration were identified, although the recoveries after i.m. administration were, subjectively, the smoothest. The carfentanil half-life did not differ significantly in the goats given naltrexone by different routes. Although it is currently recommended that the naltrexone dose be divided into s.c. and i.v. portions, this practice does not appear to offer any benefit.  相似文献   
2.
Unique features of elephant hematology are known challenges in analytical methodology like two types of monocytes typical for members of the Order Afrotheria and platelet counts of the comparatively small elephant platelet. To investigate WBC differential and platelet data generated by an impedance-based hematology analyzer without availability of validated species-specific software for recognition of elephant WBCs and platelets, compared to manual blood film review. Blood samples preserved in ethylenediaminetetraacetic acid (EDTA) of 50 elephants (n = 35 Elephas maximus and n = 15 Loxodonta africana) were used. A Mann-Whitney test for independent samples was used to compare parameters between methods and agreement was tested using Bland-Altman bias plots. All hematological variables, including absolute numbers of heterophils, lymphocytes, monocytes, eosinophils, basophils, and platelets, were significantly different (p < 0.0001) between both methods of analysis, and there was no agreement using Bland-Altman bias plots. Manual review consistently produced higher heterophil and monocyte counts as well as platelet estimates, while the automated analyzer produced higher lymphocyte, eosinophil, and basophil counts. The hematology analyzer did not properly differentiate elephant lymphocytes and monocytes, and did not accurately count elephant platelets. These findings emphasize the importance of manual blood film review as part of elephant complete blood counts in both clinical and research settings and as a basis for the development of hematological reference intervals.  相似文献   
3.
Tillage practices may reduce the organic matter content in near-surface soil horizons causing crust formation. Surface conditions may cause an increase in surface run-off, thus enhancing contaminant transfer of heavy metals or an acceleration in nutrient loss. This study examines the effect of applying crop residues to the surface of tilled soils on heavy metal losses by run-off. Losses in iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) were analysed. Run-off and sediment yield were measured on 1 m2 plots using a rainfall simulator with a constant 65 mm/h intensity. Four successive rainfall applications were performed, the first three at 25 mm each and the last at 65 mm. Added corn straw varied between 0 and 4 t/ha in the five studied treatments. After 140 mm cumulative rainfall, total heavy metal losses were as follows: Fe from 137 to 950 mg/L, Mn from 2.3 to 12.83 mg/L, Cu from 0.09 to 0.72 mg/L and Zn from 0.31 to 2.46 mg/L. Dissolved fractions were as follows: Fe from 0.014 to 0.229 mg/L, Mn from 0.034 to 1.45 mg/L, Cu from 0.002 to 0.013 mg/L and Zn from 0.02 to 0.12 mg/L. Total concentrations of the studied elements decreased exponentially due to the effect of corn straw on soil loss. However, dissolved contents of Fe and Cu scarcely varied. Significant positive linear correlations were observed between total heavy metal content and soil and sediment loss by run-off. It is concluded that the addition of straw to a soil of low fertility prevents heavy metal loss.  相似文献   
4.
OBJECTIVES: To clone and sequence the cDNA for feline preproparathyroid hormone (preproPTH) and to compare that sequence with other known parathyroid hormone (PTH) sequences. SAMPLE POPULATION: Parathyroid glands from 1 healthy cat. PROCEDURES: A cDNA library was constructed in lambda phage from feline parathyroid gland mRNA and screened with a radiolabeled canine PTH probe. Positive clones were sequenced, and nucleic acid and deduced amino acid sequences were analyzed and compared with known preproPTH and PTH sequences. RESULTS: Screening of approximately 2 X 10(5) recombinant plaques revealed 3 that hybridized with the canine PTH probe; 2 clones comprised the complete sequence for feline preproPTH. Feline preproPTH cDNA consisted of a 63-base pair (bp) 5'-untranslated region (UTR), a 348-bp coding region, and a 326-bp 3'-UTR. The coding region encoded a 115-amino acid peptide. Mature feline PTH consisted of 84 amino acids. Amino acid sequence analysis revealed that feline PTH was > 83% identical to canine, bovine, swine, equine, human, and macaque PTH and 69, 71, and 44% identical to mouse, rat, and chicken PTH, respectively. Within the region responsible for hormonal activity (amino acids 1 to 34), feline PTH was > 79% identical to other mammalian PTH sequences and 64% identical to the chicken sequence. CONCLUSIONS AND CLINICAL RELEVANCE: The amino acid sequence of PTH is conserved among mammalian species. Knowledge of the cDNA sequence for feline PTH may be useful to investigate disturbances of calcium metabolism and alterations in PTH expression in cats.  相似文献   
5.
A 47-yr-old female Asian elephant (Elephas maximus) developed a corneal stromal abscess in her right eye. The elephant was trained to open her eye for topical ophthalmic therapy, and was treated six times daily with antibiotics and an antifungal solution for almost 2 mo. Nonsteroidal anti-inflammatory drugs were used to control pain, and atropine was applied topically to dilate the pupil and provide additional comfort. Vascularization of the abscess began shortly after initiating therapy, and complete resolution was obtained by 7 wk.  相似文献   
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7.
Journal of Soils and Sediments - This study consists of the evaluation of metals acute toxicity levels taking into consideration a hypothetic scenario of dam breaking and land deposition of two...  相似文献   
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9.
The influence of fruit ripeness (half ripe, fully ripe, overripe) at the time of seed extraction on seed germination behaviour, at 25 °C and 13 °C, was studied in two Spanish pepper cultivars for canning. Seeds from half ripe fruits had a poorer behaviour than those taken from fully ripe fruits, especially at 13 °C. Room ripening and overripening of half ripe fruits improved the germination behaviour of the seeds although this behaviour was poorer than that of seeds extracted from fully ripe fruits that were allowed to overripen. Overripening of fully ripe picked fruits slightly improved germination behaviour.  相似文献   
10.
Hypocalcemia and hypomagnesemia are common in horses with sepsis and endotoxemia. We hypothesize that endotoxemia triggers a systemic inflammatory response that results in hypocalcemia and hypomagnesemia. The goal of this study was to determine the effect of endotoxin (lipopolysaccharide [LPS]) administration to healthy horses on serum parathyroid hormone (PTH), ionized calcium (Ca2+) and total calcium (tCa), ionized magnesium (Mg2+) and total magnesium (tMg), phosphate (Pi), potassium (K+), sodium (Na+), chloride (Cl-), and insulin concentrations, and on the urinary excretion of these electrolytes. Twelve mares were infused with Escherichia coli LPS (30 ng/kg/h i.v.) for 1 hour. Six mares were infused with saline (controls). In LPS-infused horses, heart rate increased significantly from (mean +/- SD) 40.0 +/- 1.3 to 70.0 +/- 9.0 beats/min, respiratory rate from 12.7 +/- 1.0 to 21.1 +/- 3.0 breaths/min, body temperature from 37.4 +/- 0.3 to 38.9 +/- 0.6 degrees C, and tumor necrosis factor-alpha concentrations from 6.6 +/- 3.5 to 507 +/- 260 pg/mL (P < .05). White blood cell count decreased significantly from 7570 +/- 600 to 1960 +/- 560 cells/ microL. Serum concentrations of Ca2+ decreased from 6.5 +/- 0.3 to 6.0 +/- 0.3 mg/dL, of Mg2+ from 0.53 +/- 0.06 to 0.43 +/- 0.04 mM, of tMg from 0.78 +/- 0.05 to 0.62 +/- 0.08 mM, of K+ from 4.3 +/- 0.4 to 3.0 +/- 0.5 mEq/L, and of Pi from 3.4 +/- 0.5 to 1.7 +/- 0.5 mg/dL (all P < .05). PTH increased significantly from 1.3 +/- 0.4 to 6.0 +/- 5.2 pM; however, in some horses (n=2), PTH did not increase despite hypocalcemia. Insulin increased significantly from 9.4 +/- 3.6 to 50.5 +/- 9.6 microIU/mL (n=3). Urinary fractional excretion of Ca2+ decreased significantly from 4.7 +/- 1.4 to 1.7 +/- 1.2%, of Mg2+ from 36.6 +/- 6.5 to 11.7 +/- 7.3%, and of K+ from 37.9 +/- 11.3 to 17.7 +/- 6.2%. Fractional excretion of Pi increased from 0.02 +/- 0.02 to 0.14 +/- 0.07% and of Na+ from 0.26 +/- 0.13% to 1.2 +/- 0.5%. No changes were found in serum tCa, Na+, and Cl- concentrations. In conclusion, endotoxemia in horses resulted in electrolyte abnormalities that included hypocalcemia, hypomagnesemia, hypokalemia, hypophosphatemia, and increased serum PTH and insulin concentrations.  相似文献   
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