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1.
RICHARD G. HARVEY 《Veterinary dermatology》1993,4(4):175-179
Abstract— The physiology of essential fatty acid metabolism in the cat is reviewed. Emphasis is placed on those aspects of the n:6 and n:3 fatty acids, their metabolites and interactions, which relate primarily to the skin. The functional roles, if known, of the fatty acids are discussed. Recent clinical research into the use of essential fatty acid supplements in the management of feline dermatoses is presented. Current indications for the therapeutic supplementation with essential fatty acids are summarised. 相似文献
2.
香精油抗蜂螨作用的研究进展 总被引:2,自引:0,他引:2
香精油及其组分具有显著的抗螨效果。萜类化合物(主要是单萜)是香精油的主要成分。占总量的90%左右。研究者通过筛选试验测定了多种香精油及其一些组分的抗螨能力。大部分表现出良好的抗螨效果。但只有少部分在蜂群试验中表现出强抗螨能力。因此,有必要对此作进一步的研究。以达到最优化目标。同时联合其它防治手段,建立一套全面的害虫防治策略,实现蜂螨的最终控制。 相似文献
3.
4.
为筛选出对草莓灰霉病菌具有显著抑菌作用的植物精油,采用熏蒸法,研究茶树精油、牛至精油等6 种植物单方精油及其复配精油对草莓灰霉病菌的体外抑菌效果。结果表明:牛至精油的抑菌效果最佳,其次为1-辛烯-3-醇和茶树精油,其抑菌效果明显优于肉桂精油、桉叶精油和茉莉酸甲酯;茶树精油、1-辛烯-3-醇和牛至精油的最低抑菌浓度(MIC)分别为200、100、100 mg/L;茶树精油与牛至精油复配具有协同增效作用,且二者以质量比1∶4 进行熏蒸时,对草莓灰霉病菌的抑制作用最强。综上,牛至精油、1-辛烯-3-醇、茶树精油及茶树精油与牛至精油复配(质量比1∶4)对草莓灰霉病菌的抑菌效果较优。该研究结果可为新型草莓保鲜剂的开发利用提供新的研究思路。 相似文献
5.
迷迭香精油对几种植物病原菌的抑菌活性研究 总被引:1,自引:0,他引:1
采用生长速率法和抑菌圈法测定了迷迭香精油对甜瓜蔓枯病菌、西瓜炭疽病菌、甜瓜灰霉病菌、甜瓜枯萎病菌、梨树腐烂病菌、柑橘黑腐病菌、油菜菌核病菌、蚕豆轮纹病菌和桃细菌性穿孔病菌的抑菌活性.结果表明:迷迭香精油对8种病原真菌都具有很好的抑菌活性,其EC50分别为843.9914、1 084.2372、483.9457、1 735.5866、1 011.7869、901.2150、356.8803、1 197.3657 μL/L;对桃细菌性穿孔病菌也具有一定的抑菌活性,浓度为100 mL/L时,抑菌圈直径为1.00 cm,最低抑菌浓度为1 000 μL/L. 相似文献
6.
为研究不同种植区西洋参氨基酸的含量和品质,按食品安全国家标准GB/T5009.124-2016,对加拿大多伦多市、陕西省留坝县、吉林省抚松县、山东省文登市来源的4 a生西洋参进行氨基酸种类和含量测定及对比分析。各产地西洋参均检测出17种氨基酸,其中含有人体必需的赖氨酸、蛋氨酸、异亮氨酸、苯丙氨酸、亮氨酸、苏氨酸、缬氨酸和半必需氨基酸精氨酸;含有蛋氨酸、亮氨酸、异亮氨酸、苯丙氨酸、赖氨酸、天冬氨酸、甘氨酸、谷氨酸和精氨酸等8种药用氨基酸。人体必需氨基酸及药用氨基酸含量对比分析结果表明,加拿大多伦多市来源西洋参的这两类氨基酸含量最高,分别为46.20 mg/g和61.93 mg/g,占总氨基酸含量的54.0%和72.3%,其次是陕西省留坝县来源的西洋参,分别为45.70 mg/g和61.63 mg/g,占总氨基酸含量的51.9%和70.0%。主成分分析及综合评价结果表明,从氨基酸含量及营养均衡性角度来看,陕西省留坝县西洋参是最接近原产地加拿大的西洋参。 相似文献
7.
《Veterinary anaesthesia and analgesia》2023,50(5):459-465
ObjectiveTo determine whether L-carvone increases the voltage threshold response to a noxious electrical stimulus in sheep.Study designProspective, blinded, randomized, crossover experimental study.AnimalsA group of six healthy adult sheep.MethodsSheep were instrumented with cranial dorsothoracic subcutaneous copper electrodes. A stimulator delivered a 10 ms square-wave stimulus at 50 pps starting at 0.1 V with a 0.2 V second–1 ramp. The stimulus stopped once two observers who were blinded to treatment noted a behavioral pain response or when a 15 V cut-off was reached. Next, 0.15 mL kg–1 of either a 50% L-carvone solution or a saline-vehicle control was administered intramuscularly, and electrical threshold responses were measured every 5–15 minutes over a 6 hour period using methods identical to the baseline. One week following the first treatment (L-carvone or control), sheep were studied using identical methods with the second treatment (control or L-carvone). Drug and time effects were evaluated using a two-way repeated measures analysis of variance, and pairwise comparisons were evaluated with Holm-Sidák tests with values of p < 0.05 considered significant.ResultsL-carvone significantly increased voltage threshold responses for most time points up to 75 minutes compared with baseline and with saline control. The last time point with a significantly different response between L-carvone and saline treatments was 5 hours after drug administration. The saline-vehicle control decreased voltage threshold responses at several time points after 3 hours.Conclusions and clinical relevanceIntramuscular L-carvone is analgesic in sheep, although the ethanol-propylene glycol vehicle may cause mild hyperalgesia. This study demonstrates that a food-derived compound can be used to relieve pain in a food-producing animal. 相似文献
8.
9.
S. C. Gupta 《Plant Breeding》1994,112(2):135-140
Screening of a population of Ocimum basilicum var. glabratum Benth., raised from seeds collected from France, West Africa and Kerala (India) was carried out for chemical composition of its essential oils. In all three collections, plants were found to be comprised of 3 chemotypes which were morphologically indistinguishable, but each chemotype was found to be capable of intercrossing freely with the other two. Selfing was carried out during 4 consecutive generations, after which three pure lines were established. Study of the selfed progeny of each collection exhibited an interesting segregation in S2 and S3 generations. Along with segregation in F2 and F3 generations of various hybrids the results can be explained by assuming a gene ‘M’ existing in 3 (or more) allelic forms: The allele M0 for biosynthesis of estragole (methyl chavicol) is dominant to allelcs M1 , for eugenol and M2 for camphor. Also, allele M1 is dominant to allele M2 . The assumption was further confirmed by testcrosses of F1 hybrids of each cross with their recessive parent. 相似文献
10.
Izquierdo MS Robaina L Juárez-Carrillo E Oliva V Hernández-Cruz CM Afonso JM 《Fish physiology and biochemistry》2008,34(2):117-127
The Δ6 and Δ5 desaturases and elongases show only very limited activity in marine fish, and little is known of the possibility
of enhancing Δ6 desaturase gene expression in these fish. The use of plant oils in marine fish diets is limited by their lack
of n−3 highly unsaturated fatty acids (HUFA) despite an abundant content of the 18C fatty acid precursor linoleic and α-linolenic
acids. The objective of the present study was to determine the ability of larval gilthead seabream to utilize vegetable oils
and assess the nutritional regulation of Δ6 desaturase gene expression. Seventeen-day-old gilthead seabream larvae were fed
during a 17-day period with one of four different microdiets formulated with either sardine fish oil (FO), soybean, rapeseed
or linseed oils, respectively, or a fifth diet containing defatted squid meal and linseed oil. Good larval survival and growth,
both in terms of total length and body weight, were obtained by feeding the larvae either rapeseed, soybean or linseed oils.
The presence of vegetable oils in the diet increased the levels of 20:2n−9 and 20:2n−6, 18:2n−9, 18:3n−6, 20:3n−6 and 20:4n−6, in larvae fed rapeseed and soybean oils in comparison to those fed FO. In addition, a sixfold increase in the relative
expression of Δ6 desaturase-like gene was found in larvae fed rapeseed and soybean oils, denoting the nutritional regulation
of desaturase activity through its gene expression in this fish species. However, feeding linseed oil did not increase the
expression of the Δ6 desaturase gene to such a high extent. 相似文献