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31.
龙蒿脂肪酸成分研究   总被引:2,自引:1,他引:2  
试验对提取的龙蒿Artemisia dracunculus油脂进行甲酯化处理,采用气相色谱技术,首次对龙蒿脂肪酸成分进行了分析,结果表明,龙蒿中含有19种脂肪酸(鉴定17种)。脂肪酸性质评价显示,龙蒿的多不饱和脂肪酸与饱和脂肪酸相对含量比(PUFA/SFA)为3.25,可见龙蒿具有降血脂功能。  相似文献   
32.
栽培乌拉尔甘草根中黄酮类和皂甙类化合物的提取与分析   总被引:1,自引:0,他引:1  
采用冷浸乙醇提取法对兰州人工引种栽培的6年生乌拉尔甘草Glycyrrhiza uralensis根中的总黄酮和总皂甙类化合物进行了提取分离,并且采用重量法和3种紫外-可见分光光度法对乌拉尔甘草根中总黄酮含量进行了测定和比较分析。结果表明,3种分光光度测定方法中,黄酮含量以直接测定法为最高,硝酸铝显色法次之,氯化铝显色法最低,直接测定法测定样品中的黄酮含量因不受显色剂干扰,测定结果相对更为准确可靠。人工栽培乌拉尔甘草相对野生甘草有效成分的含量较低,但仍可作为野生药用甘草的替代品。  相似文献   
33.
甘草的利用研究进展   总被引:49,自引:0,他引:49  
乌拉尔甘草、刺毛甘草、光果甘草、胀果甘草、刺果甘草等 5种甘草从资源分布及在医药、畜牧、食品、化工领域的应用等方面的研究进行了综述 ,对甘草的进一步开发利用提供了科学依据  相似文献   
34.
哈萨克牛四种蛋白多态与体尺性状关系的分析   总被引:1,自引:0,他引:1  
哈萨克牛 Tf、Ptf、Alb和 Pa等 4个蛋白位点分别有 4、2、2和 3种表型 ,分别受 3、2、2和 2个共显性等位基因支配。应用最小二乘法拟合线性模型 ,研究 4个蛋白位点的基因型与哈萨克牛体尺性状间的关系 ,结果表明 ,在胸深性状上 ,Tf AE型的 LSE值显著高于 Tf DE型的 LSE值 ( P<0 .0 5 ) ;在胸围性状上 ,Tf AE型的 LSE值极显著高于 Tf DE型的 LSE值 ( P<0 .0 1 ) :对于胸深性状 ,Ptf AA型的LSE值显著高于 Ptf AB型的 LSE值 ( P<0 .0 5 ) ;在腰角宽性状上 ,Alb AA型的 LSE值显著高于 Alb AB型的 LSE值 ( P<0 .0 5 ) ;对于臀端高性状 ,Pa AA型的 LSE值极显著高于 Pa AB型的 LSE值 ( P<0 .0 1 ) ;对于十字部高性状 ,Pa AA型的 LSE值显著高于 Pa AB型的 LSE值 ( P<0 .0 5 )  相似文献   
35.
Recombinant fowlpox virus (rFPV/HN) expressing Newcastle disease virus (NDV) HN gene and rFPV/HN/chIL-12 co-expressing chicken IL-12 (chIL-12) and HN (rHN/chIL-12) genes have been characterized. rHN/chIL-12 or rchIL-12, expressed by our previous construct rFPV/chIL-12, co-administered with rHN was assessed for adjuvant activities of chIL-12. Chickens were vaccinated with various amounts of rHN/chIL-12 mixed with mineral oil (MO), intramuscularly. Levels of hemagglutination-inhibition (HI) antibody production depended on the concentration of the injected rHN or rHN/chIL-12. The lower HI antibody titers were obtained in chicken groups rHN/chIL-12/7-rHN/chIL-12/9, receiving 60ng rHN/8ng chIL-12 with MO, 30ng rHN/4ng chIL-12 with MO or 15ng rHN/2ng chIL-12 with MO, respectively, compared to those in chicken groups rHN/7-rHN/9, receiving rHN with MO alone. However, chickens in group rHN/chIL-12/7 or rHN/chIL-12/8 and rHN with MO alone showed the same effective protection. Chicken group rHN/chIL-12/9 was even more protective than that in group rHN/9. When rchIL-12 was co-injected with 15ng rHN plus MO, chickens produced low levels of HI antibody titers; while higher levels of IFN-γ production and an effective protection rate (83%) were obtained. On the other hand, low levels of IFN-γ production and low protection response (50%) were obtained in chickens injected with rHN with MO alone. Taken together, when the concentration of rHN decreased to certain levels, rchIL-12 reduced HI antibody production. The increase in the induction of IFN-γ production might suggest the enhancement of the cell-mediated immunity which conferred the protection from the NDV challenge.  相似文献   
36.
研究了疑核内胆碱能神经元、去甲肾上腺素能神经元、脑啡肽能神经元对机体细胞免疫机能的影响 ,并对疑核内 3种神经元之间的相互关系进行了探讨。实验用麻醉家兔 ,分 6组进行 ,分别在疑核处通过微量注射器注入氯化乙酰胆碱 ( Ach)、密胆碱 -3( HC-3)、酒石酸去甲肾上腺素 ( NA)、6-羟基多巴胺 ( 6-OHDA)、盐酸吗啡 ( MP)、盐酸纳络酮 ( NX) ,并分别于注射前和注射后不同时间取外周血 ,测定 T细胞百分率及PHA诱导的有丝分裂原反应。结果 :Ach组上述免疫指标比注射前明显升高 ;HC-3组上述免疫指标比注射前明显降低 ;NA组上述免疫指标在注射后 30、60 min时明显低于注射前 ;6-OHDA组上述免疫指标在注射后 1 0~ 1 2 0 min时明显升高 ;MP组上述免疫指标在注射后 60、1 2 0 min时明显降低 ;NX组上述免疫指标注射前、后无明显变化。提示 :疑核增强机体细胞免疫的作用可能是通过胆碱能神经元实现的 ;疑核内的去甲肾上腺素能神经元与胆碱能神经元的作用相拮抗 ;而疑核内的脑啡肽能神经元可能对前两者的活动起一种调整作用  相似文献   
37.
The enterotoxigenic Escherichia coli (ETEC) F4ac is a major cause of diarrhoea in newborn and young pigs. The locus for the intestinal ETEC F4ac receptor (F4acR) has been mapped to pig chromosome (SSC) 13q41 with known homology to human chromosome (HSA) 3q21 and q29. However, the causative gene and mutation(s) remain unknown. The aim of this study was to characterize gene-derived markers on SSC13q41 for fine mapping of the F4acR locus, and construct a high-resolution pig–human comparative map to select positional candidate genes for F4acR. Pig-specific sequence-tagged site markers were developed for 20 genes that are located in a 6.8-Mb region on HSA3q21 and q29, and a total of 34 single-nucleotide polymorphisms (SNPs) were identified in 14 of 20 markers developed. Eighteen markers were mapped to SSC13q41, while the other two markers ( PLXNA1 and KLF15 ) were assigned to SSC13q32 and SSC7q13, respectively, by radiation hybrid mapping. This result showed that there was a small conserved segment on SSC7 corresponding to HSA3q21. A framework map comprising 18 markers on SSC13q41 was established, refining the synteny breakpoint on SSC13q41 to a region of 12.3 centiRay. The comparative radiation hybrid (RH) map revealed three interesting candidate genes for F4acR from the human genome, viz. MUC4 , MUC13 and MUC20 . Linkage analysis with six marker polymorphisms revealed that MUC4 had the most significant linkage with the F4acR locus.  相似文献   
38.
The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.  相似文献   
39.
自2003年12月26日至2005年11月14日,全世界共报告126人感染禽流感病例,其中64人死亡。2004年1月27日,我国首次公布确诊湖北鄂州、广西隆安等地发生高致病性禽流感(HPAI)疫情。2005年5月至11月30日,我国的青海、湖南、安徽、新疆等地又相继发生高致病性禽流感疫情30起,发生的疫情已得到较好的控制,确诊有3例人感染禽流感病例,其中2例死亡。近两年频发的高致病性禽流感疫情给我国家禽养殖业带来了严峻挑战。疫情发生后,家禽生产销售均普遍受阻。汉川广东温氏家禽有限公司是湖北省家禽养殖的龙头企业,年出栏肉鸡1000多万只,60%在湖北省内销售…  相似文献   
40.
This study investigated the effect of dietary nutmeg oil (NO) on growth performance, blood parameters, lipid peroxidation and heat shock protein (HSP) 70 expression in Korean native chicken (KNC) reared under hot temperature. We allocated 273 meat‐type KNCs (Hanhyup3, 4‐week‐old, body weight [BW] = 539.93 ± 1.75 g) to the following three treatments with seven replicate pens (13 birds/pen) per treatment. Three treatment diets were as follows: (a) Control, basal diet without NO supplementation; (b) NO 250; and (c) NO 500, basal diet supplemented with 250 and 500 ppm NO respectively. Diets and water were provided ad libitum throughout the 6‐week feeding trial. During overall period (0–6 weeks), no differences (p > 0.05) were observed in BW gain (BWG), feed intake (FI) and feed conversion rate (FCR) among treatments. However, the FI at 0–3 weeks decreased (p < 0.05) quadratically with increasing NO levels. Most blood parameters did not differ (p > 0.05) among treatments, although the monocyte level of the NO 500 group was considerably lower (p > 0.05) than that of the other groups. Furthermore, dietary NO did not affect serum triglyceride, cholesterol, total protein, albumin, calcium, phosphorus and alanine aminotransferase (ALT) levels (p > 0.05); however, it linearly decreased serum aspartate aminotransferase (AST) level (p < 0.05). Additionally, serum malondialdehyde (MDA) concentration decreased (p < 0.05) and heart MDA concentration was lower (p = 0.08) with increasing dietary NO supplementation. After a 3‐hr heat (35°C) challenge, the rectal temperature (RT) reduced (p < 0.05) linearly with increasing NO levels. Dietary NO did not affect liver HSP70 (p > 0.05) gene expression. In conclusion, NO potentially enhanced the ability of chickens to alleviate heat stress. Furthermore, our findings suggest that lipid oxidation inhibition by dietary NO likely mediated the enhanced heat‐stress tolerance of the chickens.  相似文献   
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