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101.
Sixteen red grape cultivars (Md. Jean Matthias, Öküzgözü, Muscat Hamburg, Cabarnet Sauvignon, Tekirda? Çekirdeksizi, Gewürztraminer, 2B/56, Kalecik karas?, Carignan, Kokulu Siyah, Alfonse Lavallée, Bo?azkere, Adakaras?, Papazkaras?, Mourvedre and Cinsaut) which are grown in Tekirda? Viticulture Research Institute were analyzed for determination of antioxidant activities, total phenolics, anthocyanins, external colour, polyphenoloxidase activities, sugar and acidity. The lowest antioxidant activity (percentage of inhibition on peroxidation in linoleic acid system; AA) was determined in Tekirda? çekirdeksiz extracts as 87.58% and the highest AA was in Mourvedre (93.78%). Total phenolic content (TP) varied from 817 to 3062 μg/ml GAE in the same varieties, respectively. The total anthocyanin (TA) content ranged from 40.3 to 990.8 mg/l fresh weight. The lowest PPO activity was found in Bo?azkere and the highest was in Kalecik karas?. The total sugar content in the analyzed varieties varied between 13.29 and 24.46%. There was stronger correlation between AA and TP than AA and TA.  相似文献   
102.
土壤中根皮苷和根皮素对桃幼苗的影响   总被引:1,自引:0,他引:1  
以一年生桃嫁接苗为试材,在盆栽条件下研究了苹果园土壤中特征酚酸类物质——根皮苷和根皮素对桃苗生物量、根系活力、根系保护性酶活性和MDA含量的影响。结果表明,根皮苷对桃幼苗的伤害显著,与对照相比,鲜质量、干质量分别降低了16.66%和21.58%,根系活力降低了33.04%,SOD、POD活性分别降低了40.80%和31.10%,MDA含量提高了116.34%。根皮素对桃苗的影响不大。高锰酸钾处理明显缓解了根皮苷对桃苗的伤害,苹果园土壤中的根皮苷含量降低了57.80%,提高了桃苗的生物量、根系活力和保护性酶活性,降低了MDA含量。综上,老龄苹果园土壤实测含量的根皮苷(0.343mg·kg~(-1))可降低桃苗的生物量,适量的高锰酸钾能缓解根皮苷的伤害作用。  相似文献   
103.
桃3种颜色果肉中10种酚类物质的测定及比较   总被引:2,自引:0,他引:2  
 优化了桃酚类物质分析的高效液相色谱法(HPLC),并测定和比较了红、黄、白色类型桃果肉酚类物质组分。以甲醇(0.1% H3PO4)为提取剂,采用C18柱(4.6 mm × 250 mm,5 μm),以甲醇(0.1% H3PO4)和水(0.1% H3PO4)为流动相梯度冲洗,流速1.0 mL · min-1,温度30 ℃,检测波长280 nm,适于桃果肉酚类组分分析。在桃果肉中检出了绿原酸、新绿原酸、儿茶素、表儿茶素、芦丁、槲皮素、没食子酸、阿魏酸、根皮苷和根皮素。不同肉色类型桃的主要酚类组成和含量存在差异,红肉桃主要成分为表儿茶素、绿原酸、儿茶素和新绿原酸,黄肉桃为新绿原酸、绿原酸和儿茶素,白肉桃为新绿原酸、儿茶素和芦丁;红肉桃含量最高的酚类为表儿茶素最高(78.91 ~ 673.90 mg · kg-1FW),黄肉桃为新绿原酸(7.28 ~ 25.57 mg · kg-1FW),白肉桃中含量最高的酚类因品种而异,规律不明显,以新绿原酸(3.17 ~ 6.16 mg · kg-1FW)和儿茶素(4.21 ~ 14.55 mg · kg-1FW)较高;各酚类含量差异显著,对于绿原酸、新绿原酸、儿茶素、表儿茶素和芦丁等桃果肉中的主要组分而言,红肉桃的含量均显著高于白肉和黄肉桃。同一肉色不同品种间一些酚类物质的含量差异显著,可用于筛选桃特异种质。  相似文献   
104.
The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds.  相似文献   
105.
ABSTRACT

To evaluate the effects of preharvest foliar application of calcium chloride (CaCl2), potassium chloride (KCl), and salicylic acid (SA) on postharvest quantitative and qualitative attributes and storage life of “Washington navel” orange, an experiment was conducted during two consecutive years. Solutions including CaCl2 (1.5% and 3%), KCl (1.5% and 3%), SA (0.015%, 0.03% and 0.045%), and the combination of CaCl2, KCl, and SA were sprayed on the canopy at the end of the first stage of fruit growth one month after full bloom (fruit diameter was 20 mm) and repeated in late September. The fruits were harvested at commercial maturity stage and were stored at 5°C with 85 ± 5% relative humidity (RH) for 90 days. Quantitative and qualitative characteristics were assessed every month. Preharvest KCl treatment had no significant effect on measured parameters. However, CaCl2 and SA treatments had the most impact on the quantitative and qualitative characteristics, such as firmness and phenolic content of fruit during storage. The SA treatment enhanced fruit appearance and nutritional value compared to the control but could not prevent the weight loss during storage. The results showed that preharvest spray of CaCl2, KCl, SA, and their combination had positive effects on storability of “Washington navel” orange fruit during storage. However, the effect of Ca and SA was more. Application of Ca, K, and SA could be beneficial for orange postharvest instead of mixed elements fertilizers.  相似文献   
106.
Alkaline stress is caused by accumulation of alkaline salts (such as NaHCO3 and Na2CO3) in the soil. This problem, common in arid and semiarid areas of Spain, results from intensive agriculture, the use of hard water, and cultivation in areas of calcareous rock. The present study examines plant metabolic responses against this stress in Brassica oleracea L. cv. Bronco in order to better understand the systems of resistance that could promote plant growth in alkaline soils, and indicates the most relevant biomarkers of alkalinity toxicity. Alkaline stress causes a sharp reduction in biomass, an accumulation of Na+, and a nutritional deficiency. With this debilitated photosynthetic capacity and the antioxidant activity, superoxide dismutase (SOD) sharply decreases and O2.- accumulates, resulting in two of the main causes of stress. Therefore the mechanisms of uptake and compartmentalisation of nutrients and detoxification of O2.- systems should be strengthened in order to remedy alkaline stress. In this work, the authors conclude that Na, P, K, Ca, Mg, and Mn ions are the best indicators of alkaline stress, due to their strong correlation with reduced leaf biomass reduction and photosynthetic pigments, together with the greater accumulation of proline and certain antioxidant enzymes such as SOD.  相似文献   
107.
Chicory (Cichorium spp.) is a valuable vegetable crop worldwide for its edible leaves and for the production of coffee substitutes from roots. Agrobacterium rhizogenes-mediated genetic transformation of two species of chicory (C. intybus and C. endivia) was investigated using Agrobacterium strain K599 harbouring p35SGFPGUS+ plasmid and two types of explants: leave and leaf stalks. This Agrobacterium strain proved to be competent in the transformation with transformation rate about (23.1%) in leaf explants of C. intybus. However, the transformation rate with C. endivia was much lower (3.6%). Moreover, the hairy roots appeared from different infection sites of the leaf explants. Several hairy roots of the two species were acquired, out of them 11 clones (C. intybus) and two clones (C. endivia) were selected due to their fast-growing character. Growth of hairy roots was determined on the basis of total root biomass accumulation. It was found that the liquid MS-basal medium seems to be the most suitable for biomass production. PCR analysis revealed foreign DNA integration in the selected transgenic hairy root clones. Notable, the transgenic hairy roots exhibited substantially higher growth rates and accumulated higher amount of inulin than non transgenic roots (WT). Also, the total phenolic compounds were determined.  相似文献   
108.
采用小分子酚醛树脂对60根海门口遗址饱水古木进行加固处理,测定加固后古木的加固收缩率、物理力学性能、表面接触角、甲醛释放量、抗流失性等性能,并将其各项评价指标与未加固古木和健康木材进行对比。结果表明:加固后古木呈浅红褐色;平均加固收缩率横向为914%,纵向为417%;基本密度由016g/cm3增加至029g/cm3;顺纹抗压强度由367MPa增加至3778MPa;三切面的表面接触角均明显增大,加固古木的表面疏水性明显增强;采用穿孔萃取法测定加固古木的甲醛释放量为1915mg/100g,因此贮存及展示环境须密封;抗流失试验中质量损失率为547%,试件中的酚醛树脂大部分固定在古木中。研究中经酚醛树脂加固后的古木各项性能均有明显提高,能够满足古木下一步的运输、贮存及展示的要求。  相似文献   
109.
Fucales are an order within the Phaeophyceae that include most of the common littoral seaweeds in temperate and subtropical coastal regions. Many species of this order have long been a part of human culture with applications as food, feedand remedies in folk medicine. Apart from their high nutritional value, these seaweeds are also a well-known reservoir of multiple bioactive compounds with great industrial interest. Among them, phlorotannins, a unique and diverse class of brown algae-exclusive phenolics, have gathered much attention during the last few years due to their numerous potential health benefits. However, due to their complex structural features, combined with the scarcity of standards, it poses a great challenge to the identification and characterization of these compounds, at least with the technology currently available. Nevertheless, much effort has been taken towards the elucidation of the structural features of phlorotannins, which have resulted in relevant insights into the chemistry of these compounds. In this context, this review addresses the major contributions and technological advances in the field of phlorotannins extraction and characterization, with a particular focus on Fucales.  相似文献   
110.
The aim of the present study was to evaluate the effect of the addition of two olive oil-derived antioxidants, hydroxytyrosol (3,4-dihydroxyphenylethanol, HT) and 3,4-dihydroxyphenylglycol (DHPG), on ovine semen during liquid storage at 5°C and 15°C. Semen was collected, pooled, diluted and then divided into aliquots supplemented with different concentrations (5 μg/ml, 10 μg/ml, 50 μg/ml and 100 μg/ml) of HT, DHPG and a mixture (MIX) of both antioxidants. Sperm motility characteristics were assessed in the different samples at 0, 6, 24, 48, 72 and 96 hr after cooling, and a fertility trial was also conducted. The results showed that the antioxidant addition did not significantly improve total and progressive motility in ovine cooled sperm maintained at 15° or 5°C. However, in samples stored at 5°C, LIN (48, 72, 96 hr), STR (0 hr) and WOB (0, 48, 72, 96 hr) values significantly decreased in comparison with control treatment when high antioxidant concentrations were added (MIX100 or HT100). When samples were maintained at 15°C, MIX50 showed significantly higher VCL values than the control treatment after 6 hr cooling, and MIX100 showed significantly lower VCL values at 96 hr after cooling. According to the artificial insemination trial, no significant differences were observed when antioxidants were added. In conclusion, the use of HT and DHPG showed small impact in sperm motility and fertility was not affected (nor detrimentally nor positively) when insemination was carried out using antioxidant-supplemented liquid sperm.  相似文献   
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