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排序方式: 共有4585条查询结果,搜索用时 15 毫秒
941.
Alpha‐lipoic acid (ALA) is a multifunction antioxidant that is produced in small amount by cells as well as its dietary provision facilitates fatty acid mobilization, energy expenditure as well as can scavenge free radicals in poultry birds. It exists in oxidized as well as reduced form, characterized by growth promoting, anti‐inflammatory, antioxidative, immunostimulatory, and hypocholesterolemic properties when fed as dietary supplement to farm animals particularly chicken birds. Recently, several studies reported that dietary supplementation of ALA can influence growth performance indicators, immunological, biochemical characteristics, lipid metabolism, and oxidative stress as well as increase antioxidant potential and storability of poultry meat and meat products. Accordingly, this paper adds the reviews and discusses the outcomes of studies documenting the effect of lipoic acid dietary fortification on growth performance, biochemical, and immunological characteristics as well as the effects on lipid peroxidation of fresh meat and meat‐based products. Furthermore, this paper also describes the possibilities of utilization of ALA as a feed additive in poultry nutrition to improve the growth performance of poultry as well as meat quality of resultant chicken birds.  相似文献   
942.

Objective

To describe a successfully managed case of polyneuropathy and respiratory failure secondary to presumed monensin intoxication.

Case Summary

A 9‐month‐old Australian Shepherd was evaluated for progressive generalized weakness and respiratory distress. Several days preceding presentation, the dog was seen playing with a monensin capsule, and had free access to a barn where the product was stored and where chewed capsules were subsequently found. The dog was presented with flaccid tetraparesis, hyperthermia, and severe respiratory distress. Bloodwork and urinalysis revealed marked increase in serum creatine kinase concentration and presumed myoglobinuria. Cardiac troponin I level was markedly increased. Management included mechanical ventilation for 5 days, fluid‐therapy, active cooling, antimicrobial therapy, analgesia, gastroprotectants, antiemetics, enteral feedings, continuous nursing care, and physiotherapy. Intravenous lipid rescue therapy was administered with lack of improvement in respiratory function and muscle strength. The patient completely recovered and was discharged after 12 days of hospitalization.

New or Unique Information Provided

Monensin intoxication should be considered in the differential diagnosis of acute polyneuromyopathy and respiratory failure in dogs with access to this compound. Respiratory failure secondary to monensin intoxication does not necessarily carry a poor prognosis if mechanical ventilation can be provided as a bridge until return of respiratory function is achieved.  相似文献   
943.
Fatty acid analyses were conducted on newly hatched and 8‐day‐old‐starved and fed Stage I phyllosoma larvae of the spiny lobster, Jasus edwardsii. Fed animals were offered excess 1.5 mm juvenile Artemia (enriched using the alga Isochrysis galbana, Tahitian isolate, T. iso.). After 8 days, there were significant increases in larval dry weight and the proportion of lipid in fed phyllosoma, whereas these parameters decreased in starved phyllosoma. The abundance of the saturated fatty acids 16 : 0 and 18 : 0 increased in both starved and fed phyllosoma, whereas the main monounsaturated fatty acids 16 : 1n‐7, 18 : 1n‐9 and 18 : 1n‐7 increased with feeding but decreased with starvation. There were no significant differences in the relative proportions of the highly unsaturated fatty acids (HUFAs) arachidonic (AA, 20 : 4n‐6), eicosapentaenoic (EPA, 20 : 5n‐3) and docosahexanoic (DHA, 22 : 6n‐3) acids between newly hatched and starved animals, whereas quantitatively DHA decreased with starvation and feeding. The DHA/EPA ratio was significantly lower in the starved and fed phyllosoma (0.5) compared with that found in the newly hatched phyllosoma (0.9). The lipid profiles of the newly hatched, starved and fed phyllosoma contained large amounts of n‐6 fatty acids resulting in low n‐3 : n‐6 ratios (2.8, 2.7 and 1.6 respectively). The importance of these results and the ability of enriched Artemia to provide a suitable fatty acid profile for this species are discussed.  相似文献   
944.
植物种子共轭亚麻酸含量分析   总被引:4,自引:0,他引:4  
以栝楼、3个石榴品种(三白玉、青皮软籽和甜绿子)和6个苦瓜品种(长白、满优青、槟城一号、开化白苦瓜一号、开化白苦瓜二号和青丰)的种子为材料分析其脂质组成和共轭亚麻酸含量.结果表明:所分析的植物种子脂质组成中最主要的为甘油三酯.其质量分数在92.6%到97.0%之间;栝楼籽油主要的脂肪酸为油酸(22.6%)、亚油酸(32.6%)和石榴酸(32.6%).而总的共轭亚麻酸(conjugated linolenic acid,CLNA)质量分数为36.9%;石榴籽中石榴酸质量分数高达73.4%~77.5%,总的CLNA 质量分数迭83.4%~87.9%;苦瓜籽α-桐酸质量分数高达56.0%~63.7%,总的CLNA质量分数达65.2%~71.9%.研究结果表明这些植物种子富含CLNA,其中栝楼籽和石榴籽中主要的CLNA为石榴酸,而苦瓜籽中主要的CLNA为α-桐酸.  相似文献   
945.
The fatty acid accumulation in broodstock influences the fecundity of spawners as well as egg quality. A comprehensive understanding of the lipid and fatty acid changes in broodstock during the reproductive period can increase our knowledge of the nutritional requirements in artificial breeding programs. The study assessed the lipid and fatty acid compositions of muscle, liver and ovary of American shad at different stages of reproductive development under reared conditions. The results indicated that there were significant differences in lipid content among ovary, liver and muscle. Mean total lipid levels in ovary, liver and muscle were 15.92%–10.87%, 13.62%–6.89%, 10.39%–6.11% respectively. During the development season, the total lipid content in muscle in stages V and VI were significantly lower than those in stages II and III. The total lipid content in liver in stages IV, V and VI was significantly lower than in stages II and III, whereas the total lipid content in the ovary increased significantly as the gonad developed and reached its highest value at stage V. From II to VI stage, the liver content of docosahexaenoic acid (DHA) decreased and the ovarian content of DHA increased, whereas the content of eicosapentaenoic acid (EPA) remained relatively constant. The content of C16:0 and C18:1n‐9 decreased in muscle and liver, but significantly increased in ovary. It is therefore suggested that the lipids were preferentially transferred from muscle and liver to ovary beginning in stage IV as the gonad matured. At stage IV, the lipid transfer accelerated, and saturated and unsaturated fatty acids, such as C16:0, C18:1n‐9, DHA, EPA and arachidonic acid, were selectively transferred to and conserved in ovaries.  相似文献   
946.
杨代勤 《水产学报》2006,30(5):676-682
研究了饲料中添用不同含量胆碱对黄鳝生长、饲料利用效率、肌肉和肝脏脂肪含量、肝体指数及消化器官4种消化酶活性的影响。结果表明,饲料中添加的胆碱含量不同,对黄鳝的影响不同,饲料中胆碱添加量在0~2.0%内,随着胆碱添加量的提高,黄鳝的生长速度会加快,饲料系数会逐步降低,肌肉、肝脏的脂肪含量及肝体指数降低,前肠、后肠和肝脏的蛋白酶、胰蛋白酶、淀粉酶和脂肪酶的活性均会相应的提高,而且饲料中的添加量达0.8%~1.0%时,这些变化显著,表明胆碱对黄鳝是不可缺少的,黄鳝饲料中胆碱的适宜添加量为0.8%~1.0%。  相似文献   
947.
将人类MCP(膜辅因子蛋白)和CD59(终末阶段同源限制因子)两种基因采用混合注射的方法,导入521枚昆明小鼠的受精卵原核中,得到原代转CD59基因小鼠14只,CD59的整合率为18.4%;转MCP基因小鼠12只,MCP的整合率为15.7%;转CD59 MCP双基因小鼠7只,双基因整合率为9.2%;转基因效率5%。通过5只存活的G0代转双基因小鼠和非转基因小鼠的繁殖,得到F1代转MCP小鼠14只,转CD59小鼠16只,转双基因小鼠10只;F1代双基因占33.3%。  相似文献   
948.
4种扁桃在6月幼果膨大期的光合速率排序为:麻壳>纸皮>克西>双果,其中麻壳品种的光合速率最高为30.22mg.dm^-2h^-1。9月份果仁成熟期,克西和双果的光合速率维持在20.30mg.dm^-2h^-1,而纸皮和麻壳则降至10.52mg.dm^-2h^-1;4种扁桃相对含水量从高到低排序为:双果>克西>麻壳>纸皮,4种扁桃在6月份的细胞膜透性从大到小排序为:克西>双果>麻壳>纸皮,9月双果的细胞膜透性是4种扁桃中最低的,从相对含水量和细胞膜透性上看双果具有较强的抗旱性。  相似文献   
949.
高温胁迫对早稻根系质膜ATPase活性及NH+4吸收的影响   总被引:5,自引:0,他引:5  
选用高温耐性品种农大228、082和高温敏感品种茉莉占、协青早B,比较研究了高温胁迫对根系质膜ATPase活性和NH4^+吸收速率的影响。结果表明,高温胁迫下,农大228和082根系质膜H^+-ATPase和Ca^2+-ATPase活性均比对照提高,而茉莉占和协青早B分别比对照大幅度下降,品种间差异显著(Duncan’s法检验)。根系质膜蛋白含量在高温胁迫后均表现下降。082的NH4^+吸收速率不受高温影响,热敏感型品种NH4^+吸收速率受高温胁迫明显下降。  相似文献   
950.
微孔过滤对茶叶儿茶素类和生物碱HPLC检测的影响   总被引:2,自引:0,他引:2  
本试验分别选用4种不同材质[尼龙66(NL66)、聚醚砜(PES)、混合纤维素(MCE)和聚四氟乙烯(PTFE)]滤膜过滤茶样浸提液,考察微孔滤膜过滤对茶叶中没食子酸、儿茶素类和嘌呤碱HPLC分析检测的影响。结果表明同种材质滤膜连续过滤获得3瓶滤液(约1mL/瓶)中的没食子酸和生物碱含量基本相当;尼龙66滤膜过滤液中的儿茶素含量存在较大的瓶间差异,但PES、MCE和PTFE滤膜过滤液并无明显的先后差别。由此可见,PES、MCE和PTFE等是茶样浸提液净化预处理较为适宜的滤膜材质,而吸附作用则可能是引起NL66滤膜过滤液中儿茶素类含量测定结果不一致的主要原因。  相似文献   
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