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511.
The effects of distiller's dried grains with solubles (DDGS) from different sources on growth performance, hematology, and immunity of hybrid tilapia, Oreochromis niloticus × Oreochromis aureus, were evaluated. Sex‐reversed, all‐male hybrid tilapia (3.72 ± 0.08 g initial weight) were fed diets in which 30% of protein in the control diet, supplied by a combination of soybean meal (SBM) and corn meal (CM) (SBM : CM ratio = 1.8), was replaced by wheat DDGS (WtDDGS), sorghum DDGS (SDDGS), whiskey DDGS (WkDDGS), or one of three corn DDGS (CDDGS 1–3) sources (control and six experimental diets) for 10 wk. Tilapia were stocked at 30 fish per aquaria (three aquaria per diet). Growth of tilapia fed diets containing DDGS sources was similar to or better than the control diet, and no nutritional deficiencies were observed. Tilapia fed the CDDGS 2 and 3 sources showed superior weight gain. Improved growth appeared to be caused by an increase in feed intake and not due to improvements in dietary nutritional value. Hematology and immunity were not affected by DDGS source. It is concluded that DDGS from all the sources examined can be included in the diet of juvenile hybrid tilapia at about 30% as a replacement of one‐third protein from SBM‐CM mixture without adverse effects.  相似文献   
512.
The effects of dietary linoleic (LA) and linolenic acids (LN) on growth and immunity of all‐male hybrid tilapia, Oreochromis niloticus × Oreochromis aureus, were evaluated for 10 wk. Fish fed 0.12% LA + 0% LN had the lowest weight gain (WG) but was not significantly different from diets containing 0.5% LA or 0.40% LA + 1.0% LN. Fish fed 1% LA had the highest WG but did not differ from diets with 0.5% LA, 2.0% LA, 0.26% LA + 0.5% LN, 0.69% LA + 2.0% LN, or diets containing both LA and LN at 0.25, 0.5, and 1.0%. Feed intake, feed efficiency, and survival did not differ among treatments. Total body n‐6 fatty acids (FAs) increased with increasing dietary levels of n‐6. Total body n‐3 FAs also appeared to increase with increasing dietary n‐3 levels but peaked at 1% of diet. Dietary treatment had no effect on hematology, immune function, or survival to Streptococcus iniae. This study indicates that both LA and LN are dietary essential for growth of hybrid tilapia. Dietary LA alone can meet the essential FA requirement, and a level of 1.14% of diet is required for optimum growth.  相似文献   
513.
514.

Background

Quantitative contrast‐enhanced ultrasonography (CEUS) can detect pancreatic perfusion changes in experimentally induced canine pancreatitis. However, its usefulness in detecting perfusion changes in naturally occurring pancreatitis is unclear.

Hypothesis/Objectives

To determine the feasibility of using CEUS to detect pancreatic and duodenal perfusion changes in naturally occurring canine pancreatitis.

Animals

Twenty‐three client‐owned dogs with pancreatitis, 12 healthy control dogs.

Methods

Dogs diagnosed with pancreatitis were prospectively included. CEUS of the pancreas and duodenum were performed. Time‐intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusion parameters were obtained for statistical analyses: time to initial up‐slope, peak time (Tp), time to wash‐out (TTW), peak intensity (PI), and area under the curve (AUC).

Results

For the pancreas, Tp of the pancreatitis group was prolonged when compared to controls (62 ± 11 seconds versus 39 ± 13 seconds; < .001). TTW also was prolonged but not significantly (268 ± 69 seconds versus 228 ± 47 seconds; = .47). PI and AUC were increased when compared to controls (95 ± 15 versus 78 ± 13 MPV; = .009 and 14,900 ± 3,400 versus 11,000 ± 2,800 MPV*s; = .013, respectively). For the duodenum, PI and AUC were significantly increased in the pancreatitis group when compared to controls.

Conclusions and Clinical Importance

Contrast‐enhanced ultrasonography can detect pancreatic perfusion changes in naturally occurring canine pancreatitis characterized by delayed peak with prolonged hyperechoic enhancement of the pancreas on CEUS. Additionally, duodenal perfusion changes secondary to pancreatitis were observed.  相似文献   
515.
Obesity has increased continuously in western countries during the last several decades and recently become a problem in developing countries. Currently, anti-obesity drugs originating from natural products are being investigated for their potential to overcome adverse effects associated with chemical drugs. Artemisinic acid, which was isolated from the well-known anti-malaria herb Artemisia annua (AA) L., was recently shown to possess anti-adipogenic effects in vitro. However, the anti-adipogenic effects of AA in animal models have not yet been investigated. Therefore, we conducted daily oral administration with AA water extract in a diet-induced obesity animal model and treated 3T3-L1 cells with AA to confirm the anti-adipogenic effects in the related protein expressions. We then evaluated the physiology, adipose tissue histology and mRNA expressions of many related genes. Inhibition of adipogenesis by the AA water extract was observed in vitro. In the animal model, weight gain was significantly lower in the AA treated group, but there were no changes in food intake volume or calories. Reductions in lipid droplet size and mRNA expression associated with adipogenesis were also observed in animal epididymal fat. This study is the first to report that AA has an anti-obese effects in vivo.  相似文献   
516.
In the present study, the detrimental effect of β-emission on pig skin was evaluated. Skin injury was modeled in mini-pigs by exposing the animals to 50 and 100 Gy of β-emission delivered by 166Ho patches. Clinicopathological and immunohistochemical changes in exposed skin were monitored for 18 weeks after β-irradiation. Radiation induced desquamation at 2~4 weeks and gradual repair of this damage was evident 6 weeks after irradiation. Changes in basal cell density and skin depth corresponded to clinically relevant changes. Skin thickness began to decrease 1 week after irradiation, and the skin was thinnest 4 weeks after irradiation. Skin thickness increased transiently during recovery from irradiation-induced skin injury, which was evident 6~8 weeks after irradiation. Epidermal expression of nuclear factor-kappa B (NF-κB) differed significantly between the untreated and irradiated areas. One week after irradiation, cyclooxygenase-2 (COX-2) expression was mostly limited to the basal cell layer and scattered among these cells. High levels of COX-2 expression were detected throughout the full depth of the skin 4 weeks after irradiation. These findings suggest that NF-κB and COX-2 play roles in epidermal cell regeneration following β-irradiation of mini-pig skin.  相似文献   
517.
Lee KS  Lim BV  Chang HK  Yang HY  Bahn GH  Paik EK  Park JH  Kim CJ 《Fitoterapia》2005,76(6):514-519
The aqueous extract of Liuweidihuang-tang given to rats at doses of 100 mg/kg/day for 10 days induced a reduction in the frequency of error and increased neurogenesis in the hippocampal dentate gyrus. Our data suggest that Liuweidihuang-tang improves spatial learning ability by increasing neurogenesis in the dentate gyrus.  相似文献   
518.
The experimental results of orthogonal cutting of maple and the modeling of the cutting mechanics are presented. The tool cutting forces were measured for different feed rates. A set of equations relating the tangential and feed forces to the tool edge width and feed rate (chip thickness) to calculate the chip and edge cutting force coefficients was developed. Then the chip force and edge force coefficients were calculated from experimentally obtained cutting forces and were plotted in a polar-coordinate system with respect to the fiber orientation of the maple disk. The polar-coordinate presentation of the cutting force results and the calculated cutting force coefficients provides an excellent visual appreciation of the relation between the cutting forces and the wood fiber orientation. Chips were also collected from various sectors of the wood disk. This analysis further identified the effects of fiber orientation and cutting forces on the types of chip formed and hence the cutting mechanics involved. By applying the calculated cutting coefficients for each tool orientation (in respect to the grain) it is possible to predict the feed and tangential forces for any feed rates. There is good agreement between the predicted and measured cutting forces.  相似文献   
519.
This article presents a systematic method for enhancing the estimation accuracy of ammonia emission from field-applied manure and for assessing the relative significance of ammonia emission factors, using the feedforward-backpropagation artificial neural network (ANN) approach.

The multivariate linear regression (MLR) method well describes the ammonia emission tendency with the emission factor variation. However, ammonia emission from manure slurry is too complex to be captured in a linear regression model. This necessitates a model which can describe complex nonlinear effects between the ammonia emission variables such as soil and manure states, climate and agronomic factors. In the present study, a principle component analysis (PCA) based preprocessing and weight partitioning method (WPM) based postprocessing ANN approach (called the PWA approach) is proposed to account for the complex nonlinear effects.

The ammonia emission is predicted with precision by the 11 emission factors, using the nonlinear ANN approach. The relative importance among the 11 emission factors is identified using the elasticity analysis in the MLR method and using the WPM in the ANN approach. The relative significance obtained quantitatively by the PWA approach in the present study gives an excellent explanation of the most important processes controlling NH3 emission.  相似文献   

520.
B. J. Kim    Y. C. Kwon    Y. H. Kwack    M. S. Lim  E. H. Park 《Plant Breeding》1999,118(5):435-438
The genus Allium includes several important vegetable and ornamental species, and is an economically important crop. The objective of this study was to determine the mode of reproduction in A. senescens L. (2n=6x= 48) and two Allium species collected in Korea. Chromosome numbers of embryo sac mother cells (EMCs) at diplotene of meiosis were 2n = 48 and unreduced in A. senescens. However, normal sexual reproduction was observed at diplotene in both A. senescens var. minor (2n = 2x= 16) and A. nutans L. (2n=4x= 32). Parthenogenetic embryogenesis also occurred in A. senescens at high frequencies among the three Allium species. Antipodal embryos in A. nutans were formed in unpollinated flowers. Normal seeds were not formed in flowers of A. senescens that had been emasculated and kept in sealed conditions. However, normal seeds were formed in the flowers that were pollinated 2 days after anthesis. In conclusion, diplospory, parthenogenesis, and pseudogamy occur in A. senescens.  相似文献   
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