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81.
82.
Two feeding experiments were carried out to evaluate the utilization of fermented soybean meal (FSBM) in diets for Pacific white shrimp (Litopenaeus vannamei). The digestibility experiment was assessed with four diets: a reference diet and three ingredient test diets containing FSBM, local and Chilean fishmeal. The growth experiment was conducted including four isonitrogenous and isocaloric diets formulated to contain the graded levels of dietary fishmeal (0 g/kg, 150 g/kg, 300 g/kg and 450 g/kg) substituted by FSBM. The results indicated that ADCs of crude protein in FSBM were high (888.4 g/kg) and equal in local fishmeal but little lower than Chilean fishmeal while without any significant differences observed in ADCs of crude lipid among the different test ingredients. After 75 days of growth trial, survival rates and feed conversion ratio were not significantly different among the experimental treatments. However, shrimp fed the diets with increasing inclusions of FSBM had a tendency to reduce weight gain and specific growth rate. Based on the correlation between weight gain and substituted fishmeal level analysed by broken‐line regression, the optimum level of fishmeal replaced by FSBM in diet was 253.6 g/kg without adverse effects on growth and feed utilization of Pacific white shrimp.  相似文献   
83.
Chronic neuroinflammation plays an important role in the development and maintenance of neuropathic pain. The compound flexibilide, which can be obtained from cultured soft coral, possesses anti-inflammatory and analgesic effects in the rat carrageenan peripheral inflammation model. In the present study, we investigated the antinociceptive properties of flexibilide in the rat chronic constriction injury (CCI) model of neuropathic pain. First, we found that a single intrathecal (i.t.) administration of flexibilide significantly attenuated CCI-induced thermal hyperalgesia at 14 days after surgery. Second, i.t. administration of 10-μg flexibilide twice daily was able to prevent the development of thermal hyperalgesia and weight-bearing deficits in CCI rats. Third, i.t. flexibilide significantly inhibited CCI-induced activation of microglia and astrocytes, as well as the upregulated proinflammatory enzyme, inducible nitric oxide synthase, in the ipsilateral spinal dorsal horn. Furthermore, flexibilide attenuated the CCI-induced downregulation of spinal transforming growth factor-β1 (TGF-β1) at 14 days after surgery. Finally, i.t. SB431542, a selective inhibitor of TGF-β type I receptor, blocked the analgesic effects of flexibilide in CCI rats. Our results suggest that flexibilide may serve as a therapeutic agent for neuropathic pain. In addition, spinal TGF-β1 may be involved in the anti-neuroinflammatory and analgesic effects of flexibilide.  相似文献   
84.
Hung PQ  Quigg C 《Science (New York, N.Y.)》1980,210(4475):1205-1211
Recent progress toward a complete theory of the weak interactions has led to sharper predictions for the properties of the hypothetical weak-force particles known as intermediate bosons. The history of speculations about intermediate bosons is briefly summarized and the (as yet negative) searches carried out for these particles are reviewed. Prospects for future searches-both direct ad indirect-are surveyed, and the consequences of finding the expected or unexpected are noted.  相似文献   
85.
86.
A biological activated carbon process was investigated for its feasibility as a tertiary treatment process for potato processing wastewaters. Bench-scale continuous complete-mix activated sludge reactors and biological activated carbon units were operated to evaluate the removal kinetics of organic materials and to determine the design parameters for a full-scale treatment unit. Raw wastewater contained 4300 mg/1, which was reduced to 130 to 340 mg/1 following the complete-mix activated sludge treatment and to 30 to 90 mg/1 after the biological activated carbon treatment.  相似文献   
87.
Three amino acid-balanced, vitamin- and mineral-fortified peanut spreads were stored at 4, 23, and 40 degrees C for 3 months. These were 69.6% peanut/19% soybean-40.5% fat, 61.9% peanut/19% soybean-44.5% fat, and 74.1% peanut/14% nonfat dry milk (NFDM)-40% fat. The peanut spreads were fortified with vitamin A, thiamin, riboflavin, vitamin B(6), vitamin C, calcium, and iron to provide 33.3% of the Recommended Dietary Allowances for children. Water-soluble vitamins were quite stable in deaerated peanut spreads. The antioxidant activity of phytochemicals in soybean prevented vitamin A degradation in soy-containing spreads, whereas the NFDM spread lost 70% of the initial content. Instron analysis detected major changes in texture when peanut spreads were stored at 40 degrees C, suggesting that the polymorphic form of lipid transformed and the proper crystallization of stabilizer was destroyed. Panelists did not detect the texture changes in peanut spreads stored at different temperatures. At 40 degrees C, the primary deteriorative changes in sensory quality were increased browning and the development of "soybean" and "oxidized" flavors as well as decreased "roasted peanutty" flavor.  相似文献   
88.
The quantitative analysis of the initial transport of fixed isotope 15-nitrogen (15N) in intact nodulated soybean plants (Glycine max [L.] Merr. cv. Williams) was investigated at the vegetative stage (36 days after planting, DAP) and pod-filling stage (91 DAP) by the 15N pulse-chase experiment. The nodulated roots were exposed to N2 gas labeled with a stable isotope 15N for 1 h, followed by 0, 1, 3 and 7 h of exposure with normal air. Plant roots and shoots were separated into three sections (basal, middle and distal parts) with the same length of the main stem or primary root. Approximately 80 and 92% of fixed N was distributed in the basal part of the nodulated roots at the vegetative and pod-filling stages by the end of 1 h of 15N2 exposure, respectively. In addition, about 90% of fixed 15N was retained in the nodules and 10% was exported to root and shoot after 1 h of 15N2 exposure at 91 DAP. The percentage distribution of 15N in the nodules at the pod-filling stage decreased from 90% to 7% during the 7 h of the chase period, and increased in the roots (14%), stems (54%), leaves (12%), pods (10%) and seeds (4%). The 15N distribution was negligible in the distal root segment, suggesting that N fixation activity was negligible and recycling fixed N from the shoot to the roots was very low in the initially short time of the experiment.  相似文献   
89.
沙质海岸木麻黄+湿地松林不同混交模式综合效益评价   总被引:1,自引:0,他引:1  
为了筛选综合效益最佳的木麻黄+湿地松混交林模式,应用层次分析法,以蓄积量、生物量、风降率、风害率、土壤有机质质量分数和土壤速效养分质量分数为指标,对沙质海岸8年生的5种木麻黄+湿地松混交林模式(木麻黄与湿地松2:4带状混交、3:3带状混交、1:3行带混交、1:2行带混交及1:1行间混交)的生长效益、防护效益和地力维护效益状况分别进行研究,在此基础上对以上5种木麻黄+湿地松混交林模式综合效益进行评价。结果表明:5种木麻黄+湿地松混交林模式综合效益大小顺序为木麻黄与湿地松3:3带状混交模式〉2:4带状混交模式〉1:2行带混交模式〉1:1行间混交模式〉1:3行带混交模式。  相似文献   
90.
2-Methylisoborneol (2-MIB) and trans-1,10-dimethyl-trans-9-decalol (geosmin) are two commonly observed taste and odor compounds present in drinking water sources. The effects of pH on the analysis of the two chemicals are investigated using a gas chromatograph and mass spectrometric detector (GC/MSD) coupled with three pre-concentration methods, namely solid-phase micro-extraction (SPME), purge-and-trap concentration (PTC), and liquid–liquid extraction (LLE). At neutral and alkaline pH conditions, the concentrations detected for both compounds remain constant. However, a substantial reduction of concentration for both chemicals is observed when the water solution pH is less than 5. Under acidic conditions (pH ≅ 2.5), the 2-MIB concentrations detected by GC/MSD coupled with SPME, PTC, and LLE are 87%, 16%, and 37% lower than those measured at pH 6–7, respectively. For geosmin, a decrease in concentration is only observed when using GC/MSD-SPME, presumably due to the higher extraction temperature compared to the other two techniques. The pH-dependent behavior was attributed to dehydration of the tertiary alcohols of 2-MIB and geosmin under acidic conditions. The dehydration for 2-MIB and geosmin is reversible, and the analysis can be mitigated by adjusting the water solution pH back to a neutral condition.  相似文献   
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