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51.
The experiment was designed to investigate the dietary factors that might enhance or interfere with astaxanthin (Ax) absorption in salmon including potentially interfering factors such as certain carotenoids (zeaxanthin and lutein), plant sterols, fibre and enhancing compounds such as cholesterol and vitamin E. Two hundred and eighty‐eight salmon (778 ± 78 g) were reared in sea water under controlled conditions and fed practical experimental diets. The experimental diets were supplemented with 40 mg Ax kg?1, in addition to various dietary factors, including cholesterol (2%), vitamin E (450 IU kg?1), wheat bran (5%), lutein (40 mg kg?1), zeaxanthin (40 mg kg?1) and phytosterol (2%). After 26 days of feeding, blood was collected and plasma was separated to determine the plasma Ax concentration. Ax was not detected in the plasma of fish fed the non‐pigmented diet. Fish fed diet containing 2% cholesterol significantly improved Ax absorption, which was reflected in the higher Ax concentration in plasma of Atlantic salmon. Other supplements including vitamin E, wheat bran, lutein, zeaxanthin and phytosterols in diet had no significant effect on plasma Ax concentration . Fish fed diet containing 2% cholesterol significantly increased cholesterol concentration in fish plasma. Phytosterol had no benefit to lower cholesterol plasma level in fish fed 2% phytosterol‐supplemented diet.  相似文献   
52.
Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection.  相似文献   
53.
Astaxanthin (AST) is a biomolecule known for its powerful antioxidant effect, which is considered of great importance in biochemical research and has great potential for application in cosmetics, as well as food products that are beneficial to human health and medicines. Unfortunately, its poor solubility in water, chemical instability, and low oral bioavailability make its applications in the cosmetic and pharmaceutical field a major challenge for the development of new products. To favor the search for alternatives to enhance and make possible the use of AST in formulations, this article aimed to review the scientific data on its application in delivery systems. The search was made in databases without time restriction, using keywords such as astaxanthin, delivery systems, skin, cosmetic, topical, and dermal. All delivery systems found, such as liposomes, particulate systems, inclusion complexes, emulsions, and films, presented peculiar advantages able to enhance AST properties, among which are stability, antioxidant potential, biological activities, and drug release. This survey showed that further studies are needed for the industrial development of new AST-containing cosmetics and topical formulations.  相似文献   
54.
温度对雨生红球藻生长、虾青素累积和抗氧化能力的影响   总被引:1,自引:0,他引:1  
本文研究了不同培养温度对雨生红球藻细胞密度、生长速率、虾青素含量、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)的影响。结果表明藻细胞密度、生长速率和虾青素含量随温度的增加先升高后下降,SOD活性 和GSH-Px活性随着温度的增加而逐渐上升,而T-AOC则随温度的增加先升高后下降,然后再升高;藻细胞密度、生长速率、虾青素含量和T-AOC均在培养温度为25℃时达到最大值,而SOD活性和GSH-Px活性在培养温度为35℃时最高;藻细胞内虾青素和抗氧化酶的抗氧化活性互为补充。本研究结果为雨生红球藻的大规模培养和虾青素的规模化生产和应用提供了理论基础。  相似文献   
55.
高pH值对中华绒螯蟹抗氧化能力及虾青素沉积的影响   总被引:2,自引:0,他引:2  
为了揭示高pH对河蟹体色的潜在影响,探讨了高pH胁迫下河蟹虾青素和抗氧化能力的变化。将河蟹饲养于6个规格为18 m2的水泥池中,养殖用水为沙滤河水(pH 7.5~8.0)。将其中三个水泥池的水用1 mol/L Na OH调pH至9.0~9.5。分别于pH调整后的2、24、48、96、192 h时采集河蟹血淋巴和头胸甲,分析头胸甲中虾青素含量、血清超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性和总抗氧化力(T-AOC)。结果表明:pH胁迫后96 h内河蟹头胸甲中虾青素含量显著下降(P0.05),96 h后虾青素含量趋于稳定;血清SOD、CAT、T-AOC呈现先上升后下降的趋势,SOD和CAT均在胁迫48 h后与对照组差异不显著,T-AOC在胁迫192 h时与对照组差异不显著。实验结果表明高pH胁迫会导致河蟹氧化应激,从而使河蟹体色变差。  相似文献   
56.
雨生红球藻异养转化产虾青素的条件研究   总被引:1,自引:0,他引:1  
对比自养转化与异养转化的虾青素产量,发现向培养基中添加乙酸钠进行异养转化可使羽生红球藻的虾青素产量由0.723 6 mg·L-1提高到1.216 8 mg· L-1;为进一步提高虾青素产量,在单因素实验基础上,选择乙酸钠浓度和硝酸钾浓度为自变量,虾青素产量为响应值,利用中心组合设计实验和响应面分析法,对转化培养基进行优化.结果表明:异养转化培养基中的乙酸钠和硝酸钾浓度对虾青素产量影响较大,在乙酸钠1.4605 g·L-1,硝酸钾0.008 4 g·L-1,磷酸二氢钾0.02 g·L-1时,虾青素产量最高,达10.908 mg·L-1,与对照相比提高了10.16倍,与自养转化相比提高了14.07倍.  相似文献   
57.
【目的】研究虾青素(AST)对脂多糖(LPS)诱导的小鼠急性肝损伤的影响。【方法】健康雄性ICR小鼠40只随机分为4组,包括对照组、AST组、LPS组和虾青素预保护组(AST+LPS组)。记录小鼠体质量并计算肝脏系数;通过ELISA法检测血清中髓过氧化物酶(MPO)含量;生物化学法测定肝组织中丙二醛(MDA)的含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性;荧光定量PCR法检测抗氧化酶SOD、GSH-Px、CAT、谷氨酸半胱氨酸连接酶催化亚基(GCLC)的mRNA相对表达量;通过HE染色观察各组肝脏细胞形态和肝损伤程度。【结果】各组小鼠初始体质量均为18 g,末次称量与初始体质量相比增加9~11 g,但各组间体质量增加无显著性差异(P0.05)。与LPS组相比,AST+LPS组小鼠肝脏系数(0.054)、血清MPO质量浓度(10.20 ng·m L~(–1))和肝组织中MDA质量摩尔浓度(2.83μmol·g~(–1))显著降低(P0.05),抗氧化酶SOD(512.14 U·mg~(–1))、GSH-Px(848.91 U·mg~(–1))和CAT(61.53 U·mg~(–1))活性显著提高(P0.05),抗氧化酶mRNA的相对表达量均显著升高(P0.05),同时肝脏损伤程度低,肝细胞形态完整,排列均匀。【结论】虾青素可保护小鼠肝细胞形态,提高肝脏抗氧化水平,调节肝组织中抗氧化酶mRNA的表达,从而缓解LPS引起的肝脏氧化应激,减轻急性肝损伤。  相似文献   
58.
Microalgal cells serve as solar-powered factories that produce pharmaceuticals, recombinant proteins (vaccines and drugs), and valuable natural byproducts that possess medicinal properties. The main advantages of microalgae as cell factories can be summarized as follows: they are fueled by photosynthesis, are carbon dioxide-neutral, have rapid growth rates, are robust, have low-cost cultivation, are easily scalable, pose no risk of human pathogenic contamination, and their valuable natural byproducts can be further processed. Despite their potential, there are many technical hurdles that need to be overcome before the commercial production of microalgal pharmaceuticals, and extensive studies regarding their impact on human health must still be conducted and the results evaluated. Clearly, much work remains to be done before microalgae can be used in the large-scale commercial production of pharmaceuticals. This review focuses on recent advancements in microalgal biotechnology and its future perspectives.  相似文献   
59.
60.
The present study investigated the effects of dietary astaxanthin on the growth, blood biochemical, antioxidant, immune and inflammatory response in lipopolysaccharide‐challenged Channa argus. A total of 0, 50, 100 and 200 mg/kg of astaxanthin were added to the basal die for 56 days. After the feeding experiment, each group was subjected to a lipopolysaccharide challenge (except for the Control group). The results showed that adding astaxanthin to the diet can significantly increase the weight gain and specific growth rate and decrease the feed conversion ratio of C. argus; the highest weight gain, specific growth rate and minimum feed conversion ratio occurred in the 100 mg/kg group. Furthermore, dietary astaxanthin supplementation can alleviate the negative effects of lipopolysaccharides by increasing the levels of alkaline phosphatase, lysozyme, complement 3, complement 4, total serum protein, albumin, globulin, superoxide dismutase, catalase and glutathione peroxidase and decrease the serum cortisol, aspartate aminotransferase, alanine aminotransferase, glutathione peroxidase, and malondialdehyde. Dietary astaxanthin supplementation also can decrease the relative expression of inflammatory genes (nuclear factor κB, interleukin‐1, interleukin‐8 and tumour necrosis factor‐α) in the liver, spleen, kidney and intestine. To summarise, dietary astaxanthin addition can improve the growth performance and attenuate the negative effects of lipopolysaccharide challenge in C. argus. The optimal amount of astaxanthin is 100 mg/kg.  相似文献   
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