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991.
长丰鲢是人工培育出的鲢鱼新品种。为充分了解长丰鲢的营养特性,更好地利用长丰鲢资源,对北方地区养殖的长丰鲢各部位主要营养成分进行分析,用气相色谱法(GC)测定其不同部位的脂肪酸种类和含量,并将其肌肉营养成分和脂肪酸组成与普通白鲢进行对比。结果表明:长丰鲢各部位间的营养成分存在差异,其中肌肉中的粗脂肪和粗蛋白质量分数较高,分别为3.00%和16.21%;鳍中灰分的质量分数为23.64%,是肌肉中的20倍;内脏中水分和脂肪的质量分数最高,分别为75.68%和7.41%。长丰鲢各部位的不饱和脂肪酸含量较高,鱼肉不饱和脂肪酸中C18∶1n9的质量分数最高,为21.20%。肌肉中ΣEPA+DHA的质量分数为8.48%,鱼头中为7.49%,高于其他部位。与普通白鲢相比,长丰鲢肌肉中的α-亚麻酸的含量高于白鲢,但ΣEPA+DHA低于白鲢,主要营养成分差别不大。 相似文献
992.
为了解猪肉产业链各环节价格的传导机制,考察各价格传导方向及传导路径是否畅通,采用中国牧业信息网及商务部2004年1月—2014年3月的月度数据,运用协整检验和向量误差修正模型对猪肉产业链各环节的价格传导机制进行实证分析。中国猪肉产业链各环节市场价格存在长期的均衡关系;误差修正模型中的误差修正的强度为2.3%,对促使市场价格系统均衡影响较小,因此不能完全依靠市场供求系统的自发力量调节猪肉产业链中各种价格的系统均衡;猪肉产业链各环节间价格传导不是完全通畅,有些环节存在1期或2期的传导时滞;猪肉产业链的价格传导表现为下游向上游传导、下游向中游传导以及中游向上游传导,是需求拉动型。应密切关注猪肉市场零售价格,以零售价格为信号,预测产业链各环节价格的近期走势,以利于养殖户和批发商准确把握市场信息,避免价格波动带来的收入损失。 相似文献
993.
Yoich TOMIMURA 《中国林业科技(英文版)》2002,(2)
This paper deals with the chemical components and the chemical structure of lignin of Chinese fir and Poplar I-214 from plantationforest. The results revealed that the contents ofchemical component in heart wood and sapwood were almost the same except ethanol-benzene extract both in Chinese fir and in Poplar I-214, The contents of ash, holocellulose, α -cellulose, pentosan, ethanol-benzene extract and cold-water extract in Poplar I-214 were higher than that in Chinesefir, The content of lignin in Poplar I-214 was lower than that in Chinese flr. Vanillin, vanillic acid and p-hydroxybenzaldehyde were found in Chinesefir while vanillin and vanillic acid, p-hydroxybenzoic acid, syringaldehyde and syringic acid werefound in Poplar I-214 in investigation of the chemical structure of lignin by using nitrobenzene oxidization method. 相似文献
994.
The Virtual Sound Intensity Analyzer is a new instrument which has more advantages than the traditional Sound Analyzer. This Analyzer is based on fast Fourie transformation and virtual instrument technique.As an application, combining software and hardware, all kinds of weight noise sound level measurement and real-time noise octave analyzes realized synchronously. The design method has been introduced from three ways, which includes hardware, software and panel. An applied example and error analyze of Virtual Sound Intensity Analyzer are given.This Analyzer is low cost, small volume. and it is also easy to operate. It can be widely used in actual applications. 相似文献
995.
CHU Zhi-qiang YOU Cheng-zhong QIN Yong-lin CHEN Wei-dong LU Hui-xia HAN Tian-quan ZHANG Sheng-dao TANG Wen-hao 《园艺学报》2005,21(9):1817-1820
AIM: To elucidate the relationship of inflammation, coagulation and cholesterol gallstone formation. METHODS: Hamsters were divided into four groups: control group (feeding normal diet), lithogenic diet (LD) 2 weeks group, LD 6 weeks group and LD+aspirin 6 weeks group. Gallstone incidence, antithrombin antigen (AT-Ⅲ:Ag), antithrombin activity (AT-Ⅲ:Ac), thrombin (F-Ⅱa:Ac), plasminogen activator inhibitor activity (PAI:Ac), plasmin activity (Plm:Ac), D-dimer:Ag and C-reactive protein (CRP) in gallbladder bile were observed as read-out parameters. RESULTS: The incidence of gallstones in control group, LD 2 weeks group, LD 6 weeks group and LD+aspirin group were 0%, 20%, 73% and 25%, respectively. AT-Ⅲ:Ag, F-Ⅱa:Ac, D-dimer and CRP in LD 2 weeks group and LD 6 weeks group were significantly higher than those in the control group (P<0.01). AT-Ⅲ:Ag, PAI:Ac, Plm:Ac, D-dimer and CRP in LD 6 weeks group were significantly higher than those in LD 2 weeks group (P<0.01). AT-Ⅲ:Ag, F-Ⅱa:Ac, PAI:Ac, D-dimer and CRP were strikingly decreased in LD+aspirin group compared with those in LD 6 weeks group (P<0.01). The level of CRP was closely correlated with the concentration of D-dimer (γ=0.752, P<0.01). CONCLUSIONS: Coagulation cascade is activated and crosslinked fibrin forms in gallbladder bile before gallstone formation. “Lithogenic bile” might play a central role in the inflammation of gallbladder mucosa, which activates extrinsic coagulation pathway and leads cholesterol gallstone formation. 相似文献
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