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11.
This study was aimed at investigating the effect of low polarity water (LPW) on the extraction of bioactive compounds from Fucus vesiculosus and to examine the influence of temperature on the extraction yield, total phenolic content, crude alginate, fucoidan content, and antioxidant activity. The extractions were performed at the temperature range of 120–200 °C with 10 °C increments, and the extraction yield increased linearly with the increasing extraction temperature, with the highest yields at 170–200 °C and with the maximum extraction yield (25.99 ± 2.22%) at 190 °C. The total phenolic content also increased with increasing temperature. The extracts showed a high antioxidant activity, measured with DPPH (2,2-Diphenyl-1-picrylhydrazyl) radicals scavenging and metal-chelating activities of 0.14 mg/mL and 1.39 mg/mL, respectively. The highest yield of alginate and crude fucoidan were found at 140 °C and 160 °C, respectively. The alginate and crude fucoidan contents of the extract were 2.13% and 22.3%, respectively. This study showed that the extraction of bioactive compounds from seaweed could be selectively maximized by controlling the polarity of an environmentally friendly solvent.  相似文献   
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Canola meal (CM) contains less crude protein (CP) and more fiber and anti-nutritional factors such as glucosinolates than soybean meal (SBM) and consequently has a lower nutrient digestibility. Therefore, processing strategies that may increase the feeding value of CM warrant study. In two experiments, the effects of extrusion of Brassica napus CM on apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE) in growing pigs, and growth performance and diet digestibility in weaned pigs were assessed. Solvent-extracted CM was extruded using a single-screw extruder at three screw speeds: 250 (CM-250), 350 (CM-350), or 450 (CM-450) rpm. In exp. 1, in a double 4 × 4 Latin square, eight ileal-cannulated barrows (initial body weight [BW], 68.1 kg) were fed corn starch-based diets containing 50% CM or extruded CM. The CM sample contained 43.2% CP, 33.2% total dietary fiber (TDF), and 8.9 µmol of total glucosinolates/g on a dry matter (DM) basis. Extrusion increased (P < 0.05) the AID of CP, reduced (P < 0.05) apparent hindgut fermentation of CP, and decreased (P < 0.05) predicted net energy (NE) value of diets. Extrusion increased diet AID and CM SID of most indispensable AA by 3.1 to 5.3%-units. In exp. 2, 200 weaned pigs (initial BW, 8.3 kg) were fed diets containing 20% SBM, CM, or extruded CM starting 2 wk postweaning for 3 wk. The CM sample contained 42.7% CP, 28.3% TDF, and 5.3 µmol total glucosinolates/g DM. Wheat-based diets provided 2.3 Mcal NE/kg and 5.1 g SID Lys/Mcal NE. Dietary inclusion of extruded CM replacing SBM decreased (P < 0.05) diet ATTD of DM, GE and CP, and DE value. Average daily feed intake, average daily gain (ADG), and gain:feed (G:F) of pigs did not differ between extruded CM and SBM diets and were not affected by extrusion, but increasing extruder screw speed linearly increased (P < 0.05) ADG for day 1 to 7 and G:F for the entire trial. In conclusion, extrusion increased diet AID and CM SID of AA but not DE and predicted NE values of CM. However, increasing extruder speed did not further increase the SID of most of the AA of CM in growing pigs. Dietary inclusion of 20% CM or extruded CM did not affect the growth performance in weaned pigs.  相似文献   
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Objective: To provide information on the ingestion, and subsequent toxicity, of raw bread dough in dogs. Case summary: A report from the ASPCA animal poison control center (APCC) files of 3 cases of ingestion of raw bread dough by dogs. Clinical signs included vomiting, ataxia, blindness, hypothermia, and recumbency. All dogs were successfully treated for ethanol toxicosis. New information: Ingestion of bread dough can cause gastric obstruction, bloat, or ethanol toxicosis. The treatment of ethanol toxicosis, including decontamination, IV fluids, management of metabolic acidosis, and hypoglycemia is discussed. Yohimbine can be used in cases where the dog is comatose or has developed severe respiratory depression.  相似文献   
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Over the past decades, the general trend towards shade reduction and intensification of cacao management has led to biodiversity losses. In the Peruvian Amazon, the regional government is heavily promoting crop conversion to shift from regionally marketed foods towards cacao (Theobroma cacao) and copoazu (Theobroma grandiflorum). While this shift is already visibly impacting the farming landscape and the lives of many smallholder farmers, little is known about the reasons that drive farmers to choose certain types of Theobroma species or cacao varieties over others. In this paper, we addressed how cacao farmers perceive and manage specific and varietal Theobroma diversity. We interviewed cacao farmers (n?=?20) during a seed-exchange fair and adapted a version of the four-square analysis to explore which Theobromas are currently adopted by farmers and why. The native cacao variety (cacao chuncho) was the one cultivated by most farmers, followed by the more industrial clonal varieties. The source of seeds and seedlings for the most cultivated varieties was a mix of donations by public institutions (for clonal varieties) and informal exchange among farmers (mainly for native and criollo varieties, and species i.e. macambo (Theobroma bicolor) and cacauillo (Theobroma speciosum)). The cacao varieties incentivized by public institutions were the least desired for future investment. The motivations for farmers to plant Theobromas was mainly based on the perceived current and potential market, but their desire to invest in a given species or variety was also based on pest resistance, traditional use, farm diversification and taste. Copoazu and CCN cacao varieties are produced by many households in large areas, while macambo, cacauillo and the cacao varieties TSH and porcelana are produced by few households in small areas. Our study suggests that agroforestry systems that include alternative Theobroma species are multi-strata and more diverse than cacao-based systems. It highlights the risks of agrobiodiversity loss associated with the promotion of industrial cacao varieties, and the importance of seed and seedling access for the development of diverse farming systems. We recommend the expansion of local seed-sharing networks and the extension of public cacao-donation campaigns to neglected and underutilized Theobromas with socio-economic and environmental benefits, in order to make the local farming systems more diverse and resilient.

  相似文献   
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The aim of the present study was to evaluate the impact of dietary fatty acids (FA) during the weaning period on expression of genes involved in the oxidation and metabolism of FA (peroxisome proliferator-activated receptor (PPAR-), stearoyl-CoA-desaturase (SCD), Δ6-desaturase (D6D), acetyl CoA carboxylase (ACC) and fatty acid synthase (FAS)). Liver samples were obtained from littermates, either on day 28 of age just before weaning, or at day 56 after the 4 weeks ad lib. provision of 5% of either animal fat, fish oil or sunflower oil. In conclusion, genes involved in the regulation of FA conversion (SCD, D6D) were influenced by the n-6 to n-3 ratio, whereas the FA oxidation, as indicated by the expression of PPAR-, was highly likely regulated by the hepatic ratio between mono- and poly-unsaturated FA. Furthermore, weaning and/or age affected the hepatic expression of genes involved in FA synthesis and conversion, but not the expression of PPAR-.  相似文献   
17.
Soy-derived isoflavones have been reported to be specific inhibitors of protein tyrosine kinases like the type 1 insulin-like growth factor receptor (IGF-1R) and the epidermal growth factor receptor (EGFR). This study was conducted to investigate, whether IGF-I and EGF stimulate porcine myoblast growth and whether the responses are influenced by isoflavones. Satellite cell-born myoblasts derived from the semimembranosus muscle of newborn piglets were treated for 26h with IGF-I or EGF alone and in combination with genistein or daidzein. The DNA amount was measured and DNA synthesis was recorded as 6 h-[(3)H]thymidine incorporation during exponential growth in serum-free basal medium. IGF-I and EGF synergistically stimulated DNA synthesis of porcine myoblast with EGF causing a greater response. Genistein (100mumol/l) effectively reduced the growth factor-mediated DNA synthesis, which was associated with an inhibition of growth factor receptor protein expression. In response to daidzein no reduction in growth factor-mediated DNA synthesis was found. Daidzein (1; 10mumol/l) combined with IGF-I caused even a slight increase in DNA amount compared with the untreated control. The expression of the IGF-1R precursor protein was reduced with 10 and 100mumol/l daidzein, whereas the EGFR expression remained unchanged with daidzein. The results suggest that dietary isoflavones may interact with growth factor-induced stimulation of pig skeletal muscle growth.  相似文献   
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Caudocranial stifle radiographs with variations in positioning were made in two greyhound cadavers. Radiographs were repeated after each of three interventions: cranial cruciate desmotomy; release of the caudal horn of the medial meniscus; complete medial meniscectomy. The joint space on medial and lateral aspects of the joint was measured by a observer who was unaware of positioning or intervention. One dog had significantly wider joint space than the other (1.0 vs. 1.5mm). The lateral aspect of the joint space was wider than the medial aspect (1.7 vs. 0.7 mm). Medial rotation of the stifle resulted in an increase of 0.4 mm in width of the lateral joint space, whereas lateral rotation of the stifle reduced the lateral joint space by an average of 0.4 mm. Decentering the X-ray beam had no significant effect on joint space width. Tension increased the width of the medial joint space by an average of 1.2 mm and the lateral aspect by an average of 1.3 mm. Cranial cruciate desmotomy resulted in an average 0.3 mm increase in width of the joint space, and medial meniscectomy with an average 0.2 mm reduction of the joint space. Although the femorotibial joint space was affected by iatrogenic stifle injuries and by medial or lateral rotation, these changes were less than the differences between the two dogs. Hence it seems unlikely that the small changes in joint space width associated with cruciate ligament desmotomy and medial meniscectomy will be detectable in clinical practice.  相似文献   
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