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91.
92.
【目的】研究意大利蜜蜂(Apis mellifera)工蜂幼虫饲料中适宜色氨酸水平,为探明意大利蜜蜂工蜂幼虫发育阶段的色氨酸营养需要提供理论依据。【方法】选用1日龄工蜂幼虫1 008只,随机分为7组,每组3个重复,每个重复48只幼虫,分别饲喂色氨酸水平为7.84、8.84、9.84、10.84、11.84、12.84和13.84 mg?g-1 的7种日粮。取5日龄工蜂幼虫虫体测定色氨酸羟化酶(tryptophan hydroxylase,TPH)基因与5羟色胺受体(5-hydroxytryptamine receptors, 5-HTR)1、2α、2β、7基因表达量;取6日龄工蜂幼虫虫体测定总蛋白、丙二醛(malondialdehyde,MDA)含量、总抗氧化能力(total antioxidant capacity,T-AOC);取6日龄工蜂幼虫血淋巴测定其中游离色氨酸水平;7日龄时,统计工蜂化蛹率;取9日龄工蜂蛹测定色氨酸体沉积量,统计21日龄工蜂出房数目,计算羽化率。【结果】色氨酸水平为10.84 mg?g-1时,6日龄工蜂化蛹率最高,6日龄工蜂幼虫虫体蛋白含量最高,9日龄工蜂蜂蛹色氨酸体沉积最多,21日龄工蜂羽化率最高。色氨酸水平为10.84-11.84 mg?g-1时,5日龄工蜂幼虫TPH基因表达量最高,5日龄工蜂幼虫5-HT受体1、2α、2β基因表达水平最高,6日龄工蜂幼虫血淋巴游离色氨酸含量最高。5日龄工蜂幼虫5-HT受体7基因表达量在色氨酸水平为7.84-11.84 mg?g-1时,处于较低水平,12.84-13.84 mg?g-1时显著高于其他水平(P<0.05)。6日龄工蜂幼虫MDA含量在色氨酸水平为7.84-11.84 mg?g-1时较低,12.84-13.84 mg?g-1时含量显著高于其他水平(P<0.05)。6日龄工蜂幼虫T-AOC在色氨酸水平为7.84-9.84 mg?g-1时处于较低水平,10.84-11.84 mg?g-1时处于较高水平,12.84-13.84 mg?g-1时显著高于其他水平。【结论】意大利蜜蜂工蜂幼虫饲料适宜色氨酸水平为10.84-11.84 mg?g-1。  相似文献   
93.
Amino acids are the building blocks for growth and the major energy source during fish larval stages. Deficient amino acids can be supplemented in the diets, overcoming problems such as low growth rates and skeletal deformities. In this study, three experimental diets were tested: a balance diet supplemented with lysine, a balance diet supplemented with tryptophan and a control with no supplementation. Trials were conducted with Diplodus sargus larvae from 1 to 25 days after hatching (DAH). A microencapsulated diet was introduced at 15 DAH in co-feeding with live feed and from 20 DAH larvae were fed only this diet. The effect of the supplemented diets was assessed in terms of survival, growth rate, skeletal deformities, ammonia excretion and activity of amino acid catabolism enzymes. The results showed a similar survival in all treatments. However, larvae given tryptophan supplementation had a lower weight on 25 DAH. No significant differences were found in ammonia excretion, frequency or type of deformities or enzymatic activity. Tryptophan and lysine supplementation failed to improve larval growth, survival or larval quality.  相似文献   
94.
Glycation is a non-enzymatic reaction, and amino acids are glycated by glucose in vivo. Tryptophan is glycated with glucose to form two types of glycated compounds, tryptophan-Amadori product and (1R, 3S)-1-(D-gluco-1, 2, 3, 4, 5-pentahydroxypentyl)-1, 2, 3, 4-tetrahydro-β-carboline-3-carboxylic acid (PHP-THβC). Although PHP-THβC can be incorporated into various chicken embryonic cells, the mechanism of its incorporation into intracellular fluids has not been clarified. In this study, we examined whether PHP-THβC once incorporated into various chicken embryonic cells can combine with proteins. Embryonic cells from the breast muscle, liver, spleen, kidney, proventriculus, gizzard, and skin were prepared and 3H-PHP-THβC was added to the culture medium at final concentrations of 0, 200, 400, 600, and 800 µM to examine the incorporation of PHP-THβC. After 18 h of incubation, radioactivity was measured in the whole-cell and protein fractions of the chicken embryonic cells. As PHP-THβC concentration increased from 0 to 600 µM, its accumulation in the whole-cell fractions of all types of chicken embryonic cells linearly increased and reached the maximum level. The saturated PHP-THβC accumulation in the whole-cell fractions suggests that PHP-THβC could be incorporated into intracellular fluids across cellular membranes by some transporter proteins. As PHP-THβC concentration increased from 0 to 800 µM, its accumulation in the protein fractions of all types of chicken embryonic cells increased in a linear manner and reached a maximum level in the 800 µM PHPTHβC treatment group. This is the first study to indicate that a part of PHP-THβC incorporated into the whole-cell fraction was detected in the protein fraction of various chicken embryonic cells.  相似文献   
95.
0~3周龄肉用仔鸡色氨酸需要量的研究   总被引:4,自引:1,他引:4  
360只肉用仔鸡随机分成5个处理 ,各试验处理在色氨酸水平为0.161 %的玉米—玉米蛋白粉半纯合基础日粮上分别添加晶体L—色氨酸0 %、0.03 %、0.06 %、0.09 %、和0.12 %。试验结果表明 :玉米—玉米蛋白粉半纯合基础日粮中添加L -色氨酸可以显著改善0 -3周龄肉用仔鸡的生产性能 (P<0.05)。在基础日粮中略微提高色氨酸水平 (0.03 % )就可以显著提高平均日增重 (P<0.01)、平均日采食量和饲料转化率 (P<0.05)。析因分析表明其原因主要在于提高了日粮营养物质的利用效率 ,同时也增加了一定的采食量。随着日粮色氨酸水平的升高 ,每鸡每日摄入色氨酸量极显著增加 ,每摄入1mg色氨酸对平均日增重和饲料转化率的作用均呈现边际递减规律 (P<0.01)。通过测定血浆中5 -羟色胺含量 ,表明它与采食量有相似的变化规律 ,因而采食量的变化可能部分是由于外周5 -羟色胺的变化而引起的 (相关系数 +0.34 ,P=0.003)。回归分析结果认为 ,0~3周龄肉用仔鸡日粮色氨酸需要量为0.236 % ,表观可利用色氨酸需要量为0.210 %,每日可利用色氨酸需要量69.73mg/天 ,可利用色氨酸需要量占日粮蛋白比例为0.96 %。  相似文献   
96.
以ATCC25922为研究对象,采用改良结晶紫染色、快速银染法和扫描电镜技术对其生物被膜进行定量和定性研究,建立大肠埃希菌生物被膜体外模型,利用优化的模型条件对249株临床分离株进行验证.采用琼脂平板计数法绘制大肠埃希菌浮游菌和被膜菌生长曲线,比较其生长特性的异同.对不同成膜能力的大肠埃希菌临床分离株进行色氨酸定量试验...  相似文献   
97.
A Zhikong scallop (Chlamys farreri Jones and Preston 1904) tryptophan 2,3‐dioxygenase (TDO) gene fragment, down‐regulated by Vibrio anguillarum challenge, was isolated using mRNA differential display in our previous work. In this paper, the full‐length TDO gene was cloned by 5′‐RACE. Chlamys farreri TDO gene consists of 1292 nucleotides encoding an expected polypeptide of 383 amino acids with an estimated molecular weight of 44.8 kDa and an isoelectric point of 6.35. The deduced amino acid sequence is 54–61% homologous to TDOs from Caenorhabditis elegans, Mus musculus, Danio rerio, Homo sapiens and Drosophila melanogaster, and shares several histidine residues important for the enzyme function in other species. Chlamys farreri TDO is expressed in the mantle, gill, digestive gland, testis, adductor muscle and kidney. Immunohistochemical analysis showed that C. farreri TDO was located mainly in the cytoplasm of most cell types. The non‐specific distribution of C. farreri TDO suggests that it is involved in various cellular processes.  相似文献   
98.
[目的]探究色氨酸羟化酶2(Tph2)基因敲除对雄性大鼠焦虑、抑郁样行为和社交行为的影响,为进一步研究五羟色胺(5-HT)系统对大鼠生长发育及行为的调控机制提供参考.[方法]以SD背景的雄性大鼠为研究对象,采用高效液相色谱串联高分辨质谱检测成年野生型大鼠(WT)和Tph2基因敲除(第6外显子(98 bp)及其前128 ...  相似文献   
99.
本研究旨在探究在饲粮中添喂色氨酸(Trp)、过瘤胃色氨酸(RPTrp)对奶牛泌乳性能、血浆指标和乳中褪黑素(MLT)含量的影响。选取30头3~5岁、2~3胎次、泌乳天数为(180±46)d的健康荷斯坦奶牛,随机分为3组,分别为对照组、试验Ⅰ组和试验Ⅱ组,每组10头。对照组饲喂全混合日粮,试验Ⅰ、Ⅱ组在对照组基础上分别添喂100 g/(d·头)色氨酸和220 g/(d·头)过瘤胃色氨酸(L-色氨酸含量≥45%)。预试期7 d,正试期60 d。结果表明:1)试验Ⅰ、Ⅱ组产奶量相比于对照组分别提高了11.78%(P0.05)和17.19%(P0.01);试验Ⅰ、Ⅱ组乳糖产量极显著高于对照组(P0.01)。2)试验Ⅰ、Ⅱ组在14:00和22:00血浆中生长激素(GH)含量极显著高于对照组(P0.01);14:00时,试验Ⅱ组血浆色氨酸含量极显著高于对照组(P0.01),各组血浆褪黑素含量无显著差异(P0.05);22:00时试验Ⅱ组血浆色氨酸含量极显著高于对照组(P0.01),试验Ⅱ组血浆褪黑素含量显著高于对照组(P0.05);试验Ⅰ组在14:00和22:00血浆色氨酸、5-羟色胺(5-HT)和褪黑素的含量与对照组均无显著差异(P0.05)。3)05:00时试验Ⅱ组乳中褪黑素含量极显著高于对照组(P0.01);18:00时各组乳中褪黑素含量无显著差异(P0.05)。4)试验Ⅰ组血浆总抗氧化能力(T-AOC)极显著高于对照组(P0.01);试验Ⅱ组血浆谷胱甘肽过氧化物酶(GSH-Px)活性极显著高于对照组(P0.01);试验Ⅰ、Ⅱ组血浆超氧化物歧化酶(SOD)活性极显著高于对照组(P0.01);试验Ⅱ组血浆丙二醛(MDA)含量极显著低于对照组(P0.01)。结果提示,添喂色氨酸[100 g/(d·头)]、过瘤胃色氨酸[220 g/(d·头)]能够提高泌乳期奶牛产奶量、血浆GH含量及抗氧化能力,其中以添喂过瘤胃色氨酸效果较好;添喂过瘤胃色氨酸[220 g/(d·头)]可提高血浆色氨酸含量及夜间血浆褪黑素含量,从而提高夜间奶牛乳中褪黑素含量。  相似文献   
100.
Soybean meal (SBM) is perhaps the most common fish meal (FM) alternative used in aquafeeds; however, SBM cannot fully replace FM in sunshine bass Morone chrysops × M. saxatilis feeds without impacting growth. Reduced production performance may be the result of subtle changes in morphology and/or physiological status. Accordingly, our objective was to assess growth, gastrointestinal integrity and stress tolerance of sunshine bass fed increasing amounts of SBM. Fish (approximately 14.5 g) were fed diets (14% lipid and 40% protein) containing increasing amounts of SBM at the expense of FM (30% FM, 20% FM, 15% FM, 10% FM, 5% FM and 0% FM) for 8 weeks. As expected, complete replacement of FM reduced growth. Although some signs of enteritis were noted, no significant differences in gut integrity were observed. Following 15-min low-water stress challenge, plasma glucose levels were elevated, particularly among fish fed increasing amounts of SBM. Cortisol response was similar, but statistical differences were not resolved for this parameter. Completely replacing FM in feeds for sunshine bass elicits overt reductions in growth. More subtle physiological changes may also result from FM replacement, including alterations in stress tolerance, and these may be important to consider in terms of the suitability of aquafeed formulations and optimal nutrition of sunshine bass.  相似文献   
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