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101.
Gonad colour, determined by accumulated carotenoids, is an important marketability factor in sea urchin products. In this study, dietary carotenoids were fed to Paracentrotus lividus in prepared diets to test their effects on the sea urchin's gonad colour. All diets had the same basic content of protein, lipid, carbohydrate, ash and energy. Four diets were enriched with: (I) all-trans β-carotene; (II) astaxanthin; (III) zeaxanthin/lutein/β-carotene; and (IV) capsanthin/zeaxanthin/lutein/cryptoxanthin/β-carotene. A fifth diet had Dunaliella bardawil algal powder containing all-trans and 9-cis β-carotene added, and a sixth one was a control diet with no added carotenoids. Sea urchins were fed the control diet (no pigments) for 4 weeks, then the six experimental diets for 8 weeks. Carotenoid concentration in the gut and gonad was determined by tri-dimensional photo-diode array high performance liquid chromatography. Four qualitative colour categories were established: brown, pale yellow, medium-orange, and mango-orange.Gonad development and test diameter increased equally in all diet treatments. Carotenoid profile and concentration in the gut were higher than in the gonad or in the feed. Total carotenoid concentration was four- to ten-fold greater in the gut than in the gonad, and carotenoid profile in the gut was different from that of the diet. Gut and gonad total carotenoids, β-carotene, and echinenone concentration were not dependent on total dietary carotenoid concentration. Total carotenoid and β-carotene concentration in the gut, and total carotenoid and echinenone concentration in the gonad were significantly dependent on dietary β-carotene concentration. The percentage of gonads with acceptable colour was positively correlated with dietary and gut β-carotene concentration. Carotenoids not normally contained in the diet of P. lividus (astaxanthin, capsanthin and capsorbin), did not accumulate in the gonad. Echinenone was found in all gut and gonad samples. Over 90% of the gonads from P. lividus fed Dunaliella algal powder diet developed the optimal mango-orange colour and this diet led to the greatest echinenone concentration.  相似文献   
102.
Apparent digestibility, deposition and retention of carotenoids in the muscle of rainbow trout, Oncorhynchus mykiss, were investigated comparing the feeding of pigments from Chlorella vulgaris against commercially available pigments at two different total lipid contents (15% and 20% lipid). Algal biomass (ALG) was included in rainbow trout diets and muscle pigmentation was compared to that obtained in trout fed diets containing a 5:3 mixture of canthaxanthin and astaxanthin (MIX) (reflecting the relative concentrations of these carotenoids in the dry alga) or those fed a diet containing astaxanthin only (AST). Apparent digestibilities of pigments and nutrients were determined by the indirect method, using Cr2 O3 as indicator, and the colour intensity and pigment concentration were assessed in the muscle, using the Roche colour card for salmonids and UV-vis spectrophotometry. After 6 weeks feeding, colour intensity was similar for the various pigment sources, achieving levels 12 to 13, yet significantly higher in fish fed the diet with the higher lipid content ( 20%) (p<0.05). Pigment concentration in the muscle was also higher in the fish fed the high-fat diet. Muscle pigment concentrations were similar for fish fed diets ALG and MIX, and over 1.5 times higher than for diet AST (p<0.05) after 6 weeks. Apparent digestibility of dry matter, crude protein, lipid, total energy and specific carotenoid concentrations were also measured. Increased dietary fat content was shown to increase the deposition and the retention of carotenoids in muscle, and the difference increased with time (deposition increase of 10–20% at week 3 and 30–40% at week 6 and retention increase of 10–15% at week 3 and 30% at week 6). Pigment digestibility also apparently increases (10–20%) under those conditions despite the fact that no significant effects in terms of apparent digestibility increase were found for dry matter, protein, lipids or energy. © Rapid Science Ltd. 1998  相似文献   
103.
类胡萝卜素是一类重要的天然色素。为了分析南瓜类胡萝卜素的成分及含量,以南瓜果肉为材料,通过对不同提取剂(甲醇、乙醇、石油醚、丙酮、丙酮-石油醚(1:1)、丙酮-石油醚(1:2)、丙酮-石油醚(1:4))和提取方法(皂化和非皂化)的筛选,优化南瓜果肉类胡萝卜素的提取条件,并应用超高效液相色谱(UPLC)技术分析了23 个南瓜品种的类胡萝卜素成分及含量。结果表明,以乙醇作为提取剂并通过皂化处理更适合南瓜果肉类胡萝卜素的提取。南瓜果肉中含有β-胡萝卜素、α-胡萝卜素和叶黄素3 种类胡萝卜素,其成分组成及含量在南瓜种内及种间均存在差异,大部分印度南瓜和中国南瓜品种的类胡萝卜素总量明显高于美洲南瓜品种。实验所优化的提取及测定方法适合南瓜果肉类胡萝卜素的定性定量分析。  相似文献   
104.
To avoid winter frost, Ponkan (Citrus reticulata Blanco cv. Ponkan) fruit in Zhejiang Province, China, is frequently harvested early, while chlorophylls are still present in the peel. Postharvest degreening of Ponkan fruit, through either ethylene fumigation or ethephon dipping, was carried out to study the effects of both treatments on color development and carotenoid accumulation. An earlier and deeper orange color development after treatments was indicated by a decline in hue angle (H°) and an increase in the citrus color index (CCI). Total carotenoid content increased, while chlorophyll content decreased during storage at 10 °C, and these changes were accelerated by both treatments. The treatments stimulated preferential accumulation of carotenoids with orange color (β-carotene and β-cryptoxanthin) while reducing the abundance of carotenoids with yellow color (lutein, violaxanthin and 9-cis-violaxanthin). Gene expression of β-carotene hydroxylase (BCH) was inhibited by both treatments, which could be related to the changes in composition of these differently colored carotenoids.  相似文献   
105.
为了给小麦类胡萝卜素含量及其相关品质性状的改良提供参考,选用了15个小麦品种作为试验材料,分别在安徽省5个生态区进行区试,测定了小麦全麦粉的类胡萝卜素含量、脂肪氧化酶( LOX )活性、白度等性状。结果表明,15个小麦品种的类胡萝卜素含量及其他被测品质性状在基因型间和环境间的差异均达到极显著水平;类胡萝卜素、蛋白质、湿面筋和淀粉含量的环境变异大于基因型变异,而LOX活性、L值,a值、b值和白度等指标的基因型变异大于环境变异。基因型和环境对小麦品种的类胡萝卜素含量及其他品质性状均有重要影响,基因型与环境互作效应亦不可忽视。  相似文献   
106.
The present research assessed the radical scavenging activity against the synthetic 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radical of the water-saturated 1-butanol extracts of wholemeal flour from 63 Triticum monococcum accessions, which originated from different eco-geographical areas. On average, T. monococcum had higher radical scavenging activity than T. turgidum and T. aestivum species, which served as controls (0.90, 0.64 and 0.70 mmol TE/kg DM, for T. monococcum, T. turgidum and T. aestivum, respectively). A significant correlation between radical scavenging activity and tocol content was observed, while no correlation existed with soluble phenolics and carotenoid contents.  相似文献   
107.
Yellow pigment concentration (YPC) in durum wheat is an important criterion in the assessment of semolina quality, particularly in determining the commercial and nutritional quality of end-products. Genetic variability of YPC and carotenoid components was analysed in 102 wild and cultivated tetraploid wheat accessions in two trials. Overall, modern cultivars showed significantly higher values of YPC compared to old cultivars and wild ssp. dicoccum and ssp. dicoccoides accessions. Total carotenoid concentration varied between 1.178 and 4.416 μg/g with an average of 2.460 μg/g. The portion of carotenoids amounted to 33.2% of the YPC in 80 wheat accessions examined in the 2006 trial. Lutein was the main component of carotenoids, followed by zeaxanthin and β-carotene. α-carotene and β-cryptoxanthin were minor components. Pigment concentration was negatively correlated with kernel weight and grain protein concentration. Significant positive correlations were found between b* index and YPC. Knowledge of the carotenoid composition and concentration is useful for wheat breeders in the development of cultivars with high yellow colour and enhanced phytochemical concentrations, and provides valuable information for evaluating contributions to health benefits from the consumption of durum wheat end-products.  相似文献   
108.
木鳖果(Momordica cochinchinensis Spreng)为葫芦科苦瓜属多年生草质藤本果树,近年来,因其果实富含类胡萝卜素等功能性成分而备受关注。本文对木鳖果整个生长发育期的生物学性状进行了详细的观察和描述,发现花后60d左右是果实色素积累的关键期。此外,利用高效液相色谱对成熟果中主要类胡萝卜素的成分、含量及其分布规律进行检测和分析。结果显示,木鳖果中检测到的类胡萝卜素总含量为7504.28 ?615.43 礸/g DW,以番茄红素和β-胡萝卜素含量最高,且主要集中在果皮和假种皮。据统计,果皮中番茄红素和β-胡萝卜素的含量分别为1236.51 ?254.83 礸/g DW、1004.32 ?235.93 礸/g DW;而假种皮中番茄红素和β-胡萝卜素的含量分别为1343.98 ?96.87 礸/g DW、 728.94 ?206.99 礸/g DW。因而,该果实可成为我国消费者摄取类胡萝卜素的有效来源之一。  相似文献   
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