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991.
Improvement of the gelling properties of meat emulsion gel by the addition of porcine sarcoplasmic proteins 总被引:1,自引:0,他引:1
The effects of porcine sarcoplasmic proteins (SP) on the physicochemical properties of meat emulsion gel were examined. Meat emulsion was prepared from water‐washed pork meat (WWM), corn oil and SP. Whole SP (W‐SP) enhanced the breaking stress of the WWM emulsion gel as well as other animal proteins in the presence of 0.2 mol/L NaCl. The breaking stress of the emulsion with W‐SP increased with an increase in corn oil content. Furthermore, this tendency was more noticeable at a lower NaCl concentration (0.15 mol/L) rather than at 0.45 mol/L NaCl. Ammonium sulfate (AS) treatment fractionated W‐SP into three portions (SP‐f1, SP‐f2 and SP‐f3), which were the precipitates at 0–50% and 50–75% AS saturation and the supernatant at 75% AS saturation, respectively. The fractions SP‐f2 and SP‐f3 increased the gel strength more than W‐SP. In particular, the fraction SP‐f3 increased the gel strength approximately 10‐fold compared to the control. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis analysis showed that SP‐f3 had several kinds of proteins and a main protein with a molecular mass of 35 kDa, which corresponded to glyceraldehyde 3‐phosphate dehydrogenase. These results indicate that the influence of SP should not be ignored when processing of low‐salt meat products and the fraction SP‐f3 has a gel‐enhancing factor for myofibrillar proteins. 相似文献
992.
几种牧草与春小麦抑盐效应比较研究 总被引:1,自引:0,他引:1
通过田间试验,测定了种植牧草和春小麦对土壤可溶性盐分和盐离子的影响。结果表明:种植牧草脱盐作用明显,而种植春小麦脱盐效果不明显;种植春小麦、豌豆、红豆草和毛苕子,使0~20cm土层的盐分分别下降16.2%、28.9%、18.5%和45.1%,差异较大的原因是蔓生型的豌豆和毛苕子郁闭度大于直立型的小麦和红豆草;种植牧草降低了0~20cm土层的SO42-、Na+、K+、Ca2+和Na+/K+,而种植春小麦仅降低SO42-、K+、Ca2+,提高了Na+和Na+/K+。由此可见,种植牧草改良盐碱地的作用优于种植春小麦。 相似文献
993.
将猪细小病毒病油乳剂灭活疫苗在2~8℃保存12~15个月后,进行了物理性状、无菌检验、安全检验及效力检验,检验结果符合<中华人民共和国兽用生物制品质量标准>. 相似文献
994.
H-FABP基因型对中畜黑猪I系生长性能的影响 总被引:7,自引:4,他引:7
利用PCR RFLP技术(限制性内切酶采用HinfⅠ和HaeⅢ)检测了培育品种77头中畜黑猪I系的心肌脂肪酸结合蛋白(H FABP)基因座位的遗传变异,同时对H FABP的不同PCR RFLP基因型对生产性能的影响作了初步统计分析,旨在探讨利用H FABP进行肉质性状辅助选择,是否对生产性能产生不利影响。结果表明,在H FABP基因5′上游和内含子2 区段,均发现HinfⅠRFLP 和HaeⅢRFLP、HinfⅠ* RFLP;结果显示,在HinfⅠRFLP位点上,HH和hh 2种基因型间个体170日龄体重差异显著(P<0.05),除此之外,未发现其它酶切位点的不同基因型个体生长性能之间的显著差异。研究结果为今后开展猪肉质性状和生产性能的分子辅助选育奠定应用基础。 相似文献
995.
抗猪SIgA单克隆抗体的研制 总被引:7,自引:0,他引:7
采用饱和硫酸铵盐析、SephadexG-200柱层析和离子交换柱层析技术,从猪初乳中提纯分泌型IgA(SIgA)。经SDS-PAGE电泳鉴定,纯化的SIgA达到电泳纯。以此纯化的SIgA,采用长程免疫法免疫BALB/c小鼠,取4次免疫后的脾细胞与SP2/0骨髓瘤细胞用PEG-1500进行细胞融合,第1次融合率为79.7%,第2次融合率为60.3%。建立间接ELISA,用于检测杂交瘤细胞上清中的单克隆抗体.初检阳性率分别为4.1%、16.8%。经2次亚克隆反复筛选获得了2株能稳定分泌抗猪SIgA单克隆抗体的杂交瘤细胞株,命名为CA6、5D4。ELISA和Western-blotting证实,所获得的单抗能特异性针对SIgA。CA6、5D4经反复冻存、复苏及多次传代,仍能分泌高效价抗体.CA6分泌抗体属IgM、κ型,而5D4分泌抗体属IgG1、κ型。 相似文献
996.
The effect of level and source of nutrients in late gestation on food intake, milk yield, milk composition and fertility in the subsequent lactation were evaluated in a randomized block design experiment involving 76 cows. Four experimental diets, based on grass silage, were offered to provide two levels of metabolizable energy (ME) intake (80 and 125 MJ/cow/day) either from 100:0 or 40:60 forage:concentrate (F:C) ratios for the last 28 days of gestation. Post-calving all cows were offered the same grass silage supplemented with 7 kg/day concentrates. For treatments 80 ME, 125 ME and 100:0 F:C, 40:60 F:C total dry matter (DM) intakes were 6.8, 10.5, 9.0 and 8.4 kg DM/day and ME intakes were 80, 126, 102 and 104 MJ/day, respectively, during the last 4 weeks of gestation. For weeks 1-16 of the subsequent lactation, treatment 125 ME increased milk fat content and yield but had no effect on food intake, milk protein content or onset of cyclicity. Treatment 125 ME increased condition score and live weight at calving. Altering the F:C ratio of the diets in late gestation had no effect on food intake, milk yield, milk composition or on the onset of cyclicity in the subsequent lactation. Cow parity and level of nutrient intake in late gestation provided the best fit relationships for the yields of fat and fat plus protein (R2 relationships=0.49 and 0.52, respectively) during weeks 1-16 of lactation. It is concluded that increasing nutrient intake in late gestation increased milk fat content and yield but had no effect on milk protein concentration. The improved milk fat content and yield observed in a previous study was due to increased nutrient intake rather than altering the F:C ratio. Furthermore there was no measurable benefit in food intake or animal performance in the subsequent lactation through feeding concentrates in late gestation. 相似文献
997.
Shaila Salokhe Angshuman Sarkar Samindranath Mukherjee 《Pesticide biochemistry and physiology》2006,85(2):84-90
The effect of sublethal concentrations, 0.00141% (LC20), 0.00251% (LC30), and 0.0036% (LC40) of a dispersible formulation of an acylurea insect growth regulator, flufenoxuron (Cascade) on certain biochemical parameters in the larvae of Tribolium castaneum was investigated. When neonates were fed on diet treated with sublethal concentrations for 24 h, it was observed that at all concentrations tested, there was a significant reduction in chitin content on the 15th day of development. Total soluble protein content at LC20 and LC30 decreased with increasing age of the larvae. At LC20 and LC40 concentrations there was a progressive increase in the protein: chitin ratio as a function of increase in age of the larvae. SDS-PAGE analysis of the larval tissue extracts indicated gross quantitative changes in some of the protein bands (MW 50-97 kDa). Western blot analysis revealed significant increase in the level of HSP70 in the extracts of larvae fed on LC30 treated diet, on the 7th and 10th day of development in the decreasing order. Conversely, a significant decrease in the hyper-phosphorylated form of p34cdc2 kinase due to flufenoxuron treatment indicating modulation of cell cycle regulation was observed. Thus, sublethal concentrations of flufenoxuron alter expression of developmentally regulated proteins, HSP70 and p34cdc2 and chitin formation in a stage-specific manner thereby resulting developmental abnormalities in T. castaneum. 相似文献
998.
Elevated levels of nitrate-nitrogen (NO3-N) in the surficial aquifer above the drinking water quality standard, i.e. maximum contaminant limit (MCL; 10 mg L−1), have been reported in some part of central Florida citrus production regions. Soils in this region are very sandy (sand content >95%), hence are vulnerable to leaching of soluble nutrients and chemicals below the rooting depth of the trees. The objective of this research was to develop N and irrigation best management practices for citrus in sandy soils to maintain optimal crop yield and quality, and to minimize potential leaching of nitrate below the root zone. Six years of field experiment was conducted in a high productive (mean fruit yield > 80 Mg ha−1yr−1) >20-year-old ‘Hamlin’ orange trees [Citrus sinensis (L.) Osbeck] on ‘Cleopatra mandarin’ (Citrus reticulata Blanco) rootstock grown on a well drained Tavares fine sand (hyperthermic, uncoated, Typic Quartzipsamments) in Highland county, FL. Nitrogen rates ranged from 112 to 280 kg ha−1 yr−1 applied as fertigation (FRT), water soluble granular (WSG), 50:50 mix of FRT and WSG, and controlled-release fertilizer (CRF). Tensiometers were used to monitor the soil water content as a basis to schedule optimal irrigation. Fruit yield response over the entire range of N rates was greater for the FRT and WSG sources as compared to that for the WSG + FRT or CRF sources. Using the regression analysis of the fruit yield in relation to N rate, the optimum N rate appeared to be at 260 kg ha−1 yr−1. Based on fruit production response in this study, the N requirement for production of 1 Mg of fruit varied from 2.2 to 2.6 kg across four N sources. This study demonstrated an increased N uptake efficiency, as a result of best management of N and irrigation applications. The optimal N and K concentration in the 4–6-month-old spring flush leaves were 26–30, and 15–18 g kg−1, respectively. However, fruit yield response showed no significant relationship with concentrations of P in the 4–6-month-old spring flush leaves over a range of 0.8–2.4 g kg−1. The results of fate and transport of N in soil and in soil solution with application of different rates and sources of N, and components of citrus tree N budget, are reported in a companion paper. 相似文献
999.
1000.
利用聚丙烯酰胺凝胶电泳技术,对采自北方玉米主产区的23个玉米灰斑病菌菌株进行可溶性蛋白质和同工酶电泳图谱分析及聚类分析,从蛋白质和酶学的多态性水平上分析玉米灰斑病菌的生理分化特征.研究表明,玉米灰斑病菌在可溶性蛋白质和SOD、MDH、PPO、POD、EST、CAT等的同工酶谱存在差异,不同菌株之间某些同工酶谱带数和同一迁移率谱带的亮度和色泽差异非常显著,说明菌株间的多态性可在同工酶水平上得到反映.研究还发现,来自不同地区的菌株同工酶谱带无明显的变化规律,反映出病菌同工酶的变异与地理位置关系不密切,也表明该病菌可能具有较广泛的地域适应性. 相似文献