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1.
Hashim MS  Devi KS 《Fitoterapia》2003,74(7-8):670-676
Extracts from the stem bark of Streblus asper possess insecticidal activity against the fifth instar of Dysdercus cingulatus. Methanolic extract showed an LC(50) value of 5.56 microg/insect. Partition with chloroform increased the insecticidal activity (LC(50) 2.01 microg/insect). Three polyphenolic rich fractions were obtained from silica-gel column chromatography of the chloroform fraction and found to have noteworthy insecticidal activity (LC(50): 1.82 microg, 2.70 microg, 2.26 microg/insect) by topical application. This may provide a useful beginning for the development of biopesticides.  相似文献   
2.
A 6‐week broiler study was conducted to evaluate whether subjecting the intestinal microflora of broilers to the effect of weekly variations in feed ingredients could be ameliorated by the inclusion of yeast‐derived feed additives: a yeast cell wall extract (YCW), live yeast culture (LY) or their combination (YCW + LY). Recent changes in ingredient prices have motivated producers to formulate diets not necessarily based primarily on corn and soya bean meal. Intestinal microflora in birds can vary significantly based on the ingredient composition of their diet, and the make‐up of the flora can influence overall bird performance. Within the three nutrient phases of this study, birds were fed either a traditional corn–soya ingredient profile or a variable‐ingredient regimen, which had weekly changes in the ingredient composition. There were consistent ameliorative effects of the yeast treatments in both the corn–soya and the variable‐ingredient groups throughout all 6 weeks, with the YCW + LY combination showing a reduced effect when compared to either product fed alone. The effectiveness of YCW and LY on ameliorating the effects of weekly ingredient variations appeared most effective during the starter and grower phases, but was less significant during the sixth week.  相似文献   
3.
Based on biochemical assays and electrophoretical methods, the inhibitory effects of three plant meals (soybean meal, wheat meal, winged bean meal) on digestive alkaline proteases of discus were investigated. Casein assays revealed that increasing levels of soybean meal caused a linear inhibitory effect on activity of protease. SDS-PAGE images revealed that trypsin and chymotrypsin were the inhibited enzymes. Soybean showed the lowest inhibition rate followed by wheat meal and raw winged bean. There was a quadratic relationship between wheat meal levels and its inhibition of protease acitivity. The highest inhibitory effect was obtained with the winged bean meal with inhibition of caseinolytic activities ranging from 3.6–98.6%. Results from this study showed the potential of both soybean meal and wheat meal as ingredients for practical diet for discus, while demonstrating the need for further improvement in processing method for winged bean meal.  相似文献   
4.
Encephalitogenic T cells specific for myelin basic protein share common V beta 8 peptide sequences in their T cell receptor (TCR) that can induce autoregulatory T cells and antibodies that prevent clinical signs of experimental autoimmune encephalomyelitis (EAE). It is not known, however, if TCR peptides can treat established disease. To test its therapeutic value, TCR-V beta 8-39-59 peptide was injected into rats with clinical signs of EAE. This treatment reduced disease severity and speeded recovery, apparently by boosting anti-V beta 8 T cells and antibodies raised naturally in response to encephalitogenic V beta 8+ T cells. These results demonstrate that synthetic TCR peptides can be used therapeutically, and implicate the TCR-V beta 8-39-59 sequence as a natural idiotope involved in EAE recovery. Similarly, human TCR peptides may be effective in enhancing natural regulation of autoreactive T cells that share common V genes.  相似文献   
5.
A dried high fiber product from bambangan (Mangifera pajang Kort.) fruit pulp was prepared and evaluated for proximate composition, functional properties, and soluble and insoluble dietary fiber composition. Mangifera pajang fibrous (MPF) consisted of 4.7% moisture, 0.8% fat, 4% protein, and 30 mg total polyphenol per g of dry sample, and 9, 79 and 88% soluble, insoluble and total dietary fiber, respectively. Water holding capacity, oil holding capacity, swelling, and solubility were found to be 9 g/g dry sample, 4 g/g dry sample, 16 mL/g dry sample, and 11%, respectively. The glucose dialysis retardation index of MPF was approximately double that of cellulose fiber. Soluble dietary fiber contained mannose, arabinose, glucose, rhamnose, erythrose, galactose, xylose, and fucose at 1.51, 0.72, 0.39, 0.16, 0.14, 0.05, 0.04, and 0.01%, respectively, with 5.8% uronic acid, while insoluble dietary fiber was composed of arabinose (18.47%), glucose (4.46%), mannose (3.15%), rhamnose (1.65%), galactose (1.20%), xylose (0.99%), and fucose (0.26%) with 15.5% uronic acid and 33.1% klason lignin. These characteristics indicate that MPF is a rich source of dietary fiber and has physicochemical properties which make it suitable as an added ingredient in various food products and/or dietetic, low-calorie high-fiber foods to enhance their nutraceutical properties.  相似文献   
6.
The effects of thiopentone and propofol on oesophageal pressures were examined in 39 bitches. The dogs were premedicated with either atropine (n = 13), acepromazine maleate (n = 13) or a combination of atropine and acepromazine. Anaesthesia was induced with either thiopentone (15 dogs) or propofol (24 dogs), both given intravenously. Immediately following the induction of anaesthesia, gastric pressure and lower oesophageal sphincter pressure (LOSP) were measured and oesophageal barrier pressure determined. There were no significant differences attributable to the premedication regimens used but both LOSP and barrier pressure were significantly lower in the dogs anaesthetised with propofol compared to the animals given thiopentone (LOSP 12-2 ± 4-2 cm H2O propofol group versus 26-8 ± 6-5 cm H2O thiopentone group).  相似文献   
7.
This experiment was carried out to evaluate the effects of the probiotic, Lactobacillus acidophilus , on the growth performance, haematology parameters and immunoglobulin concentration in African catfish Clarias gariepinus fingerling. Two experimental diets were formulated to contain 35 g kg−1 crude protein and 10 g kg−1 lipids accordingly and fed three times daily for 12 weeks to 25 C. gariepinus fingerlings per fibreglass tank in 12 replicates each. The control diet was prepared with no probiotic supplementation whereas the second diet was prepared supplemented with a probiotic, L. acidophilus , containing about 3.01 × 107 colonies/g of diet. The results show that growth performance [specific growth rate (SGR) and relative growth rate (RGR)], nutrient utilization [protein efficiency ratio (PER) and feed conversion ratio (FCR)] and survival were significantly ( P <0.05) higher in fish maintained on the probiotic-supplemented diet compared with those on the control diet. Haematology parameters (packed cell volume, haemoglobin, erythrocyte sedimentation rate, red blood cell and white blood cell, total serum protein, Ca2+, Mg2+, Cl, glucose and cholesterol) and total immunoglobulin concentrations were also significantly better in fish fed the probiotic-supplemented diet than in the control. Although the water quality parameters monitored were better in the fish fed the probiotic-supplemented diet than in the control, the parameters were not significantly different ( P >0.05). From the results of this experiment, we conclude that L. acidophilus can be used as a probiotic agent in African catfish culture, to enhance fish health, survival and better feed efficiency and growth performance.  相似文献   
8.
Aquaculture International - Single or combined effect of yeast, galactooligosaccharide (GOS), mannanoligosaccharide (MOS), and β-glucan was evaluated on the growth performance, nutrient...  相似文献   
9.
Most research works on the production frontier in aquaculture focus on efficiency measurement using either Stochastic Production Frontier (SPF) or Data Envelopment Analysis (DEA). The studies on productivity growth in aquaculture were limited, perhaps due to lack of time-series data. Nevertheless, total factor productivity analysis (TFP) in fish farms has started gaining popularity in recent years. In addition, the majority of the efficiency studies have centered on technical efficiency analysis but substantial increases in the output levels can be fully realized through improving overall economic efficiency. Therefore, this review suggests that future research should estimate all three efficiency indices (i.e., technical, allocative and economic efficiencies).  相似文献   
10.
对马来西亚2年和4年生巨草竹属天然林分的形态与解剖特征进行了研究。形态特征随着竹秆的年龄和高度发生变化。4年生薄壁组织和纤维的细胞壁厚度比2年生竹薄壁组织和纤维的细胞壁厚。在两个年龄组中,底部和上部的维管束的频率比中部频率大,在秆壁中部,2年和4年竹秆的导管直径没有区别。竹子的解剖结构与含水率和基本密度密切相关。  相似文献   
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