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81.
动物α干扰素具有高效广谱的抗病毒作用,通过农杆菌介导法将35S驱动的干扰素基因ChIFN-α转化烟草,Southern杂交和Western杂交进行目的基因的转化、表达检测,重组蛋白的数量通过ELISA测定,对获得的转基因烟草植株进行TMV接种实验,结果表明ChIFN-α基因的转化赋予了转基因烟草对TMV的抗性,进一步的荧光定量PCR差异表达检测结果表明,该抗性可能与转基因烟草体内防卫基因PR-la、抗病N基因和信号转导MAPK基因受到上调表达有关。 相似文献
82.
Tim Bouts Nicola Harrison Karla Berry Polly Taylor Andrew Routh Frank Gasthuys 《Veterinary anaesthesia and analgesia》2010,37(3):207-214
ObjectiveInvestigate physiological and sedative/anaesthetic effects of xylazine, medetomidine or dexmedetomidine combined with ketamine in free-ranging Bennett's wallabies.Study designProspective clinical trial.AnimalsTwenty-six adult free-ranging Bennett's wallabies.MethodsAnimals were darted intramuscularly with one of three treatments: xylazine and ketamine, 2.0 and 15.0 mg kg?1, respectively (XK): medetomidine and ketamine 0.1 and 5.0 mg kg?1 (MK) and dexmedetomidine and ketamine 0.05 and 5.0 mg kg?1 (DMK). Body weights were estimated. If the animal was still laterally recumbent after 45 minutes of anaesthesia, then an alpha-2 adrenoceptor antagonist, atipamezole, was administered (XK: 0.4 mg kg?1, MK: 5 mg kg?1, DMK: 2.5 mg kg?1). Heart rate (HR) and respiratory rate (fR) were recorded at 5-minute intervals and temperature at 10-minute intervals. Venous blood was taken 30 minutes after initial injection. Statistical analysis utilized anova. p < 0.05 was considered significant.ResultsAnimals became recumbent rapidly in all groups. XK animals had muscle twitches, responded to external stimuli, and three animals required additional dosing; this was not observed in the MK and DMK groups. HR (mean ± SD beats minute?1) in XK (81 ± 4) was significantly higher than MK (74 ± 2) and DMK (67 ± 4). There were no differences in fR, temperature, blood-gas and biochemical values between groups. More animals in MK (9/10) and DMK (5/6) needed antagonism of anaesthesia compared with XK (1/10). There were no adverse effects after anaesthesia.Conclusion and clinical relevanceCardio-respiratory effects were similar in all groups. There were fewer muscle twitches and reactions to external stimuli in MK and DMK. Duration of anaesthesia was shorter in XK; most animals in MK and DMK needed atipamezole to assist recovery. All three treatments provided satisfactory sedation/anaesthesia and are suitable for use in Bennett's wallabies. 相似文献
83.
辽宁绒山羊抑制素A基因遗传变异与双羔性状的关联分析 总被引:1,自引:0,他引:1
以抑制素A基因(Inhibin alpha subunit gene,INHA)作为辽宁绒山羊双羔性状的候选基因,以便为绒山羊育种工作中分子标记选择提供理论依据。运用测序法寻找辽宁绒山羊INHA基因单核苷酸多态性,筛查到一个新的多态位点-446TC,该位点位于INHA基因的启动子区域。运用PCR-RFLP法验证并分析该位点在辽宁绒山羊双羔群体和单羔群体间的多态性。结果表明,在辽宁绒山羊中双羔和单羔群体中分布A、B两个等位基因,处于中度多态。经χ2检验,样本在该位点未达到Hardy-Weinberg平衡状态(P0.05),不同基因型在辽宁绒山羊单、双胎群体上差异达到显著水平(P0.05)。 相似文献
84.
ORIGINAL ARTICLE: 2‐Oxoglutaric acid administration diminishes fundectomy‐induced osteopenia in pigs
E. Śliwa 《Journal of animal physiology and animal nutrition》2010,94(5):e86-e95
Partial surgical removal of the stomach (fundectomy, FX) leads to osteopenia in animals and humans. FX adversely affects the bone. 2‐oxoglutaric acid is a precursor of glutamine and hydroxyproline – the most abundant amino acid of collagen. The aim of the study was to investigate the effects of 2‐oxoglutaric acid on FX‐evoked osteopenia in pigs. Eighteen castrated male pigs of the Pu?awska breed were used. Twelve pigs were subjected to FX and divided into two groups: FX + AKG (the AKG group; AKG at the daily dosage of 0.4 g/kg of body weight) and FX + Placebo (the FXC group; received CaCO3 as placebo). Remaining six pigs were sham‐operated (the SHO group). The pigs were euthanized at the age of 8 months and long bones were collected. Area bone mineral density (aBMD) and bone mineral content (BMC) were measured; morphology, geometry and biomechanical properties were determined. Moreover, the serum concentrations of selected hormones and one marker of bone metabolism were determined. FX caused osteopenia in the pigs and treatment with AKG greatly reduced these effects of FX in pigs. Negative effect of fundectomy on the skeletal system leading to decreased bone mass in pigs is associated with lowered body gain and activity of the gastric–hypothalamic–pituitary axis. Better definitions of each of the local and systemic hormonal and structural components associated with fundectomy‐induced decreased bone mass that separately and together determine the whole bone properties may lead to identify opportunities for prevention. 相似文献
85.
普通小麦及近缘粗山羊草α-醇溶蛋白基因的克降、定位与进化分析 总被引:2,自引:0,他引:2
通过特异PCR引物设计,从普通小麦品种(豫麦34和烟农19)和粗山羊草(T9、T197、T48、T176和T17)中扩增、克隆了7个新的α-醇溶蛋白基因,分别命名为Gli-YM34、Gli-YN19、Gli-T9、Gli-T197、Gli-T48、Gli-T176和Gli-T17,基因序列长度为846~891 bp,编码282~297个氨基酸残基,都具有α-醇溶蛋白的典型结构特点。其中Gli-YM34和Gli-YN19基因推导的醇溶蛋白都含有一个额外的半胱氨酸残基,可能对面筋品质有正向作用。根据α-醇溶蛋白氨基酸序列所具有的4种T细胞抗原表位和多聚谷氨酰胺重复区的平均长度以及中国春缺体四体分析,将来自普通小麦品种的Gli-YM34和Gli-YN19基因定位在6D染色体上的Gli-D2位点,而且Gli-YM34和Gli-YN19与来自粗山羊草的α-醇溶蛋白基因具有很高的序列相似性,进一步证明粗山羊草是普通小麦D基因组的供体。在克隆的4个典型α-醇溶蛋白基因中检测到21个SNP和1个9 bp的缺失。系统进化分析表明,α-醇溶蛋白基因与低分子量谷蛋白亚基基因关系较近,在大约43.69百万年时分化,与ω-醇溶蛋白和HMW-GS基因亲缘关系较远,它们的分化时间大约为79.39百万年。 相似文献
86.
对多花黑麦草等28种牧草样品进行了脂肪酸组成的测定,并进行分析比较。结果表明,α-亚麻酸是牧草中含量最高的脂肪酸,占脂肪酸组成的43.78%。多不饱和脂肪酸占牧草脂肪酸组成的54.71%,占不饱和性脂肪酸的95.18%。说明牧草的不饱和性脂肪酸主要是二键以上的多不饱和脂肪酸。禾本科牧草中,多花黑麦草及狼尾草属的牧草α-亚麻酸含量较高,其中多花黑麦草69.9%;象草(N51)67.6%;红象草62.2%;杂交狼尾草61.0%。禾本科与豆科牧草的α-亚麻酸含量差异不显著。 相似文献
87.
88.
The effect of tree cover on the biomass and diversity of the herbaceous layer in a Mediterranean dehesa
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C. López‐Carrasco A. López‐Sánchez A. San Miguel S. Roig 《Grass and Forage Science》2015,70(4):639-650
Mediterranean dehesas are an archetypal example of high nature value farmland in Europe. To better understand the interactions between trees and grasslands in the conservation and management of the dehesa, we measured, over 3 years, the contribution of scattered trees to the diversity and biomass dry‐matter (DM) yield of the herb layer and the relationship between the herb layer (biomass and diversity interaction) and the trees. The study was based on 135 subplots representing four aspects and three distances from fifteen trees selected randomly in a plot within a dehesa in central Spain. The specific questions were the following: (i) To what extent do trees affect biomass of the herbaceous layer? (ii) What is the relationship between herbaceous layer biomass and species diversity under the influence of trees? and (iii) What are the effects of trees and small‐scale topography on the herbaceous diversity? Results differed between years depending on water availability. Legume and forb DM yields were highest at the edge of the tree crown and beyond the canopy. Species richness was positively related to legume DM yield, and both were higher at the bottom of the hillside, especially in dry conditions. Given the importance of tree influence on the biomass and diversity of grasslands, maintaining proper agroforestry management practices for trees and grasslands is important for conserving dehesa diversity and productivity under the conditions of high climatic and soil variability in Mediterranean dehesas. 相似文献
89.
Bai XM Ma QG Zhao LH Xi L Ji C 《Journal of animal physiology and animal nutrition》2012,96(6):955-961
The current study was carried out to determine the effects of alpha‐lipoic acid (LA) supplementation during late‐gestation and lactation on antioxidative ability and performance of sows and their nursing piglets. A total of 160 multiparous sows were randomly allocated to four treatments with 40 replicates per treatment according to parity number and backfat (BF) thickness. Sows were fed 1 of 4 diets from day 85 of gestation to day 21 of lactation. Diets were control without LA; 400 ppm LA supplementation; 600 ppm LA supplementation; and 800 ppm LA supplementation. BF thickness of sows was determined on day 85 and 110 of gestation and days 1 and 21 of lactation. Piglet bodyweight was measured at birth, days 7, 14 and 21. Blood samples were obtained from the sows, and average daily feed intake (ADFI) of the sows during lactation was recorded. There were no differences in BF thickness or ADFI among treatment groups. Dietary LA supplementation resulted in a decrease in blood urea nitrogen (p < 0.01) concentration at days 110 of gestation. Dietary 800 ppm LA increased serum glutathione peroxidase (GSH‐Px) activity (p < 0.05) and reduced maleic dialdehyde levels (p < 0.01) of sows compared with the control diet at days 21 of lactation. Alpha‐lipoic acid supplementation increased the birthweight and weaning weight of piglets (p < 0.01) compared with the control group. Weight gains of piglets from sows fed the 800 ppm LA diets were greater (p < 0.01) between days 7 and 14 compared with piglets from control sows. Weight gains of piglets from sows fed the LA‐supplemented diets were greater between days 14 and 21 (p < 0.05) and between days 1 and 21 (p < 0.01) compared with piglets from control‐fed sows. In conclusion, the results indicate that antioxidant LA was effective in enhancing antioxidant enzymes activity and improving the performance of sows and their nursing piglets. 相似文献
90.
Heather K DiMaio Knych Vanessa Covarrubias Eugene P Steffey 《Veterinary anaesthesia and analgesia》2012,39(6):574-583
ObjectiveTo describe selected pharmacodynamic effects of detomidine and yohimbine when administered alone and in sequence.Study designRandomized crossover design.AnimalsNine healthy adult horses aged 9 ± 4 years and weighing 561 ± 56 kg.MethodsThree dose regimens were employed in the current study. 1) 0.03 mg kg?1 detomidine IV, 2) 0.2 mg kg?1 yohimbine IV and 3) 0.03 mg kg?1 detomidine IV followed 15 minutes later by 0.2 mg kg?1 yohimbine IV. Each horse received all three treatments with a minimum of 1 week between treatments. Blood samples were obtained and plasma analyzed for detomidine and yohimbine concentrations by liquid chromatography-mass spectrometry. Behavioral effects, heart rate and rhythm, glucose, packed cell volume and plasma proteins were monitored.ResultsYohimbine rapidly reversed the sedative effects of detomidine in the horse. Additionally, yohimbine effectively returned heart rate and the percent of atrio-ventricular conduction disturbances to pre-detomidine values when administered 15 minutes post-detomidine administration. Plasma glucose was significantly increased following detomidine administration. The detomidine induced hyperglycemia was effectively reduced by yohimbine administration. Effects on packed cell volume and plasma proteins were variable.Conclusions and clinical relevanceIntravenous administration of yohimbine effectively reversed detomidine induced sedation, bradycardia, atrio-ventricular heart block and hyperglycemia. 相似文献