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51.
52.
OBJECTIVE: To investigate the effects of oral administration of activated charcoal (AC) and urine alkalinization via oral administration of sodium bicarbonate on the pharmacokinetics of orally administered carprofen in dogs. ANIMALS: 6 neutered male Beagles. PROCEDURES: Each dog underwent 3 experiments (6-week interval between experiments). The dogs received a single dose of carprofen (16 mg/kg) orally at the beginning of each experiment; after 30 minutes, sodium bicarbonate (40 mg/kg, PO), AC solution (2.5 g/kg, PO), or no other treatments were administered. Plasma concentrations of unchanged carprofen were determined via high-performance liquid chromatography at intervals until 48 hours after carprofen administration. Data were analyzed by use of a Student paired t test or Wilcoxon matched-pairs rank test. RESULTS: Compared with the control treatment, administration of AC decreased plasma carprofen concentrations (mean +/- SD maximum concentration was 85.9 +/- 11.9 mg/L and 58.1 +/- 17.6 mg/L, and area under the time-concentration curve was 960 +/- 233 mg/L x h and 373 +/- 133 mg/L x h after control and AC treatment, respectively). The elimination half-life remained constant. Administration of sodium bicarbonate had no effect on plasma drug concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: After oral administration of carprofen in dogs, administration of AC effectively decreased maximum plasma carprofen concentration, compared with the control treatment, probably by decreasing carprofen absorption. Results suggest that AC can be used to reduce systemic carprofen absorption in dogs receiving an overdose of carprofen. Oral administration of 1 dose of sodium bicarbonate had no apparent impact on carprofen kinetics in dogs.  相似文献   
53.
The objective of this research was to determine the optimum dietary supplementation level of a probiotic (PowerLac?), for improving Nile tilapia Oreochromis niloticus growth performance and feed utilization, as well as enhanced protection against disease. For laboratory experimentation, a completely randomized experimental design, consisting of four treatments of a dietary probiotic (PowerLac?, containing Lactobacillus lactis D1813) supplementation at different levels (0.25, 0.5, 1.0 and 2.0 g kg?1), against a control (0 g kg?1), was performed for 8 weeks (of culture period). For field experiments, three treatments of different dietary probiotic supplementation levels (0.25, 0.5 and 1.0 g kg?1), plus a control, were employed for 22 weeks (of culture period). Under controlled experimental conditions, in the first experiment, significantly higher fish final body weight, growth and lower food conversion ratio (FCR) were achieved by treatments with dietary probiotic supplementations of 0.25 and 0.5 g kg?1 (P < 0.05). In strong partial support of this, at field experimentation level, a dietary PowerLac? supplementation of 0.5 g kg?1 showed the most pronounced results, as indicated by the higher growth, and protein and lipid retention, as well as lower FCR, and reduced mortality following the Aeromonas hydrophila challenge test (P < 0.05).  相似文献   
54.
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Over the last two decades, China's outward foreign direct investment (OFDI) has expanded rapidly. The country is now the world's second-largest source of OFDI. China is often viewed as a monolithic investor, however, without sufficient attention to the differences between investments by state-owned enterprises (SOEs) and private enterprises (PEs). To shed light on the internal complexity and heterogeneity of Chinese OFDI, we construct a panel dataset of investments in the U.S. across the 50 states and Washington, D.C. from 2005 to 2017, which we analyze using a spatial autoregressive model. We find clear evidence that the ownership structure of Chinese firms affects investment strategy and entry mode. Statistical analysis indicates that SOEs are more likely to pursue greenfield investment motivated by market-seeking and resource-seeking objectives, while PEs pursue mergers and acquisitions in order to obtain strategic assets. We also detect a positive and significant relationship between the presence of Chinese overseas communities and OFDI, with the strength of the correlation depending on ownership structure. Finally, we find that Chinese OFDI is spatially dependent, meaning that investments flow to states where they are already concentrated nearby.  相似文献   
56.
Wu  Mia M.  He  Hong S.  Liang  Yu  Huang  Chao 《Landscape Ecology》2020,35(10):2321-2337
Landscape Ecology - The rate and trajectory of forest landscape recovery after a volcanic eruption rely largely on available seed sources and patterns of seed dispersal. However, quantifying the...  相似文献   
57.
A study of the salinity effect on mineral content in rice genotypes differing in salt tolerance was conducted in a factorial Completely Randomized Design experiment. The results indicated that the genotypes developed differently by mutation conventional breeding. NS15 represented as salt-sensitive, Pokkali was included as an internationally salt-tolerant check and Iratom24 was moderately tolerant. The content of Na+, Ca2+, Mg2+ and Cl? followed an increasing pattern in roots and shoots of all the rice genotypes due to increasing salinity levels except Ca2+ and Mg2+ in the root. However, the concentration of K+ showed more or less an increasing pattern in root and a decreasing pattern in shoot. The concentration of Na+ and Ca2+ sharply increased with increasing the salinity levels in both the roots and shoots of NS15. The concentration of K+ sharply decreased in shoot and increased in the root of susceptible genotype NS15 with increasing salinity over 6 dS m?1 salinity levels, where the transformation of K+ from root to shoot was disrupted by Na+. The Cl? content sharply increased with increasing salinity in the root of NS15 as compared to shoot. The effect of different salinity levels on Na+/K+ ratio in the shoots of the selected rice genotypes sharply increased in susceptible genotype NS15 as compared to the other genotypes.  相似文献   
58.

Background

In Maine Coon (MC) cats the c.91G > C mutation in the gene MYBPC3, coding for cardiac myosin binding protein C (cMyBP-C), is associated with feline hypertrophic cardiomyopathy (fHCM). The mutation causes a substitution of an alanine for a proline at residue 31 (p.A31P) of cMyBP-C. The pattern of inheritance has been considered autosomal dominant based on a single pedigree. However, larger studies are needed to establish the significance of cats being heterozygous or homozygous for the mutation with respect to echocardiographic indices and the probability of developing fHCM. The objective of the present study was to establish the clinical significance of being homozygous or heterozygous for the p.A31P cMyBP-C mutation in young to middle-aged cats.

Methods

The cohort consisted of 332 MC cats, 282 cats < 4 years (85%). All cats were examined by 2-D and M-mode echocardiography. DNA was extracted from blood samples or buccal swabs and screened for the p.A31P cMyBP-C mutation in exon 3 of the gene, using polymerase chain reaction followed by DNA sequencing.

Results

The fHCM prevalence was 6.3% in the cohort. Eighteen cats were homozygous and 89 cats were heterozygous for the mutation. The odds ratio for having fHCM for homozygous cats was 21.6 (95% confidence interval 7.01-66.2) - when the group of equivocal cats was categorized as non-affected. Overall, 50% of the cats that were homozygous for the mutation had fHCM. p.A31P heterozygosity was not associated with a significant odds ratio for fHCM. In cats in the 4 to 6 years of age range a similar, non significant, odds ratio was seen in heterozygous cats. Only two cats over four years were homozygous and both were diagnosed with fHCM.

Conclusion

As there is no significant odds ratio associated with being heterozygous for the pA31P cMyBP-C mutation at this age, the mutation must have a very low penetrance in this group. From our data it would appear that most MC cats that develop fHCM due to the p.A31P mutation prior to the age of approximately 6 years do so because they are homozygous for this mutation.  相似文献   
59.
ABSTRACT

A 120-day feeding trial was conducted in floating cages to evaluate growth performance and digestibility of Nile tilapia (Oreochromis niloticus) juveniles fed diets containing different levels of poultry by-product meal (PBM) as a replacement for fishmeal. Nile Tilapia with an average body weight of 56.6 ± 0.28 g were used in this experiment. Five diets were formulated to contain graded levels of PBM at 0%, 5%, 10%, 20%, and 30% poultry by-product meal (PBM) and are referred as PBM0, PBM5, PBM10, PBM20, and PBM30, respectively. Groups of 25 Nile tilapia were fed close to the apparent satiation, three times a day. The results showed that growth performance, survival and whole-body composition for fish fed the experimental diets were not significantly different (P > .05) than fish fed the control diet. Apparent digestibility of dry matter, protein, lipid and amino acids of fish fed the PBM20 and PBM30 were lower compared to the other treatments (P < .05). The PBM dietary levels significantly lowered total protein, high-density-lipoprotein (HDL) and cholesterol concentration. The results of this study indicated that good quality PBM can be used up to 30% in commercial diets for Nile tilapia without any adverse effect.  相似文献   
60.
Experiments revealed that successful interspecific crosses both at diploid and tetraploid levels among Corchorus olitorius, C. capsularis and C. trilocularis were possible. The crosses between C. acutangulus with any of the above three species were not successful.  相似文献   
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