首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   65篇
  免费   0篇
林业   2篇
农学   3篇
  28篇
综合类   4篇
农作物   11篇
水产渔业   7篇
畜牧兽医   3篇
园艺   5篇
植物保护   2篇
  2022年   1篇
  2021年   2篇
  2020年   1篇
  2019年   5篇
  2018年   6篇
  2017年   8篇
  2016年   5篇
  2015年   2篇
  2014年   2篇
  2013年   18篇
  2012年   3篇
  2011年   4篇
  2009年   2篇
  2008年   3篇
  2007年   1篇
  1985年   1篇
  1984年   1篇
排序方式: 共有65条查询结果,搜索用时 31 毫秒
1.
ABSTRACT

Roots of young ‘Golden Delicious’ apple on M9 rootstock were inoculated with four strains of Azotobacter chroococcum, which were isolated from various soils. Effects of these strains in combination with different levels of nitrogen (N) fertilizer and compost on plant growth and nutrient uptake were studied over two seasons. Therefore, a factorial arrangement included four strains of A. chroococcum, two levels of N-fertilizer (0 and 35 mg N kg?1soil of ammonium nitrate) and two levels of compost (0 and 12 g kg?1 soil of air-dried vermicompost). Among the four strains, AFA146 was the most beneficial strain, as it increased leaf area, leaf potassium (K), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and boron (B) uptake and root N, phosphorus (P), potassium (K), Mn, and Zn. The combination of AFA146 strain, compost and N fertilizer increased leaf uptake of Ca, Mg, Fe, Mn, Zn, and B, and root uptake of P, K, Ca, Mg, Mn, and copper (Cu), and root dry weight.  相似文献   
2.
Seed yield and quality are affected by water stress occurring at the reproductive stage of crops. Foliar application of micronutrients has been introduced as an agronomic approach to cope with such conditions. This study was undertaken to evaluate the effects of born (B) and zinc (Zn) on seed quantity and quality of spring safflower under late season water deficit. The experimental design was a split factorial in an randomized complete block (RCB) with three replications. The results showed that water deficit during flowering and seed-filling significantly decreased almost all traits compared to control only in 2014. Averaged over the 2 years, seedling length and vigor index were increased by Zn in all irrigation regimes. Germination rate and seed weight were increased by B and Zn in all irrigation treatments. It was concluded that foliar application of 350?ppm B and 1000?ppm Zn can considerably enhance seed yield and quality of safflower grown under terminal drought.  相似文献   
3.

This study was aimed at characterizing the anthocyanins and phenolics profile in different varieties of pigmented corn and wheat and in some of their milling fractions. Acid/ethanol extracts were used to assess total anthocyanins, overall antioxidant activity, the overall polyphenol profile, and for evaluating the inhibition of pancreatic α-amylase and of intestinal α-glucosidase. Both enzymes were inhibited in a dose-dependent manner by all extracts, but individual extracts had specific effects on each enzyme. Anti-inflammatory response was evaluated by using acid-free extracts and Caco-2 cells transiently transfected with a luciferase reporter gene responding to cytokine stimulation. The immune response of interleukin-stimulated cells decreased significantly in a dose-dependent manner in the presence of 20–50 μM/l anthocyanins from all grains extracts, again with a different efficiency. The inhibitory ability and the anti-inflammatory capability of these extracts are in most cases higher than in similar extracts from other sources, suggesting that activities in each extract may imply specific synergies between anthocyanins and other phenolics.

  相似文献   
4.
Imprinted genes display biased expression of paternal and maternal alleles in mammals. They are marked through epigenetic process during gametogenesis. Characterization of imprinted genes has expanded our understanding of the regulation and function of genes. In the current study, 22 experimentally validated imprinted genes in bovine (Bos Taurus) were analysed. Several supervised machine learning algorithms and attribute weighting methods were used to find characteristics of different types of imprinted genes and suggest a classification method for finding maternally and paternally expressed genes in bovine. For assessing the best model and comparing attributes in other organisms, we have also conducted a comparative analysis for human and sheep imprinted genes. According to the results of the present study, GC contents 10 and 100 kb upstream, Gly and Gln amino acids, Ile/ATC codon usage, LINE and SINE in 100kbup and length of first intron were significantly different between the maternal and paternal genes in cattle. Considering all species together, we found that GC content 100 kb up, LINE 100 kb up and the frequency of amino acids like Gly, Gln and Met were the most important attributes for identifying the paternal and maternal imprinted genes. These findings could imply conservation pattern in the attributes among these species.  相似文献   
5.
6.
Salinity is one of the major agricultural problems in arid and ?semi-arid regions. Considering the variation of plant’s ?sensitivity to salinity during growth, a greenhouse study with completely randomized design? was conducted to determine the relative salinity tolerance of Quinoa (Chenopodium quinoa Willd.) at different growth stages from seedling establishment to maturity (establishment, flowering and seed filling) by evaluating the Salinity Threshold Value (STV). Eight levels of ECi (i.e., Non-saline, 2, 4, 8, 12, 15, 20, 25 dSm?1) with four replications and five levels (i.e., Non-saline, 10, 15, 20, 25 dSm?1) with three triplications were applied at first and two last growth stages, respectively. A ?comparison was performed on some growth and yield parameters of plants irrigated by considering STV (T) and ?plants irrigated permanently by mentioned salinity levels regardless of STV (P) to choose ?which method (P or T) is better at each salinity level. The STV was ?evaluated 8, 20 and 15 dSm?1 at each growth stage, respectively. Seedling of Quinoa was more sensitive to salinity than the mature plant. Therefore, after establishment Quinoa has the ?feasibility of irrigation by high-saline waters. The (P) ?method was suitable only if the freshwater was available during all growth period of the plant; otherwise at higher salinities irrigation should be performed by considering STV (T method) to minimize the intensity of growth and yield reduction and to prevent yield loss at very high salinities. To achieve this, if high-saline water is available it’s possible to ?use plant propagation techniques or cultivating Quinoa simultaneously with seasonal rainfall.?  相似文献   
7.
Journal of Plant Diseases and Protection - Black spot disease is the most common diseases of landscape roses and is caused by Diplocarpon rosae Wolf. In Rosa multiflora, the screening of black...  相似文献   
8.
Four-day-old seedlings of spring wheat (Triticum aestivum L. cv. Marvdasht) can tolerate severe dehydration and recover after re-watering. In order to clarify tolerance mechanism, in a completely randomized design, the seedlings were exposed to drought by complete water cessation for 10 and 20 days, followed by re-watering for 3 and 7 days. Upon dehydration, the activity of α-amylase increased whereas growth parameters; photosynthetic pigments; and the activities of lipoxygenase, indole acetic acid (IAA) oxidase, and ascorbate peroxidase (APX) decreased. The activity of APX and the expression of its gene, however, increased after re-watering. Prolonged dehydration was also accompanied by increase in sucrose, soluble proteins, fructans, and certain amino acids, e.g. proline, glutamine, and valine. The results indicated that during dehydration, 4-day-old wheat seedlings shifted their energy expenditure from basal metabolism to withstand water deficiency via lowering the activity of membrane-damaging enzymes and enhancing the production of osmoprotectants.  相似文献   
9.
As global mercury emissions from coal fire power plants increase with the continuing rise of coal consumption, mercury capture methods are being developed to prevent mercury??s escape into the atmosphere. Titanium dioxide (TiO2) in the presence of ultra violet light (UV-A; ?? max ??360?nm) and oxygen will capture mercury as the solid product HgO(s). Testing the effects of TiO2 in the presence of other pollutants has so far been limited. We have performed kinetic and product studies of mercury adsorption in the presence of the gaseous flue co-pollutant NO2(g). We extensively studied the gas-phase reaction of NO2(g) with Hg (g) 0 . We compared the gas-phase reaction to the same reaction performed in the presence of thin TiO2 particle surfaces from 0 to 100?% relative humidity. The second-order rate constant was measured to be k?=?(3.5?±?0.5)?×?10?35?cm6 molecules?2?s?1, independent of the presence of titania or the total surface area available for adsorption. Exposure of NO2(g) to titania surfaces that were already saturated in captured mercury (HgO(s)) increased total mercury uptake onto the surface. We discuss the implications of this study to the capture of mercury emissions prior to release to the atmosphere.  相似文献   
10.
Background:Methadone therapy is a major protocol in opioid addiction cases in many health care systems. Population-based studies have shown that in addicted people, the genetic profile affects their response to methadone therapy. Therefore, this study designed to examine the frequency of two SNPs of the CYP2B6 gene (rs3745274 and rs3211371) in addicted cases in two methadone-responders and methadone non-responders groups. Methods:A total of 199 opioid-addicted individuals and 117 unaffected control subjects were genotyped for rs3745274 and rs3211371 polymorphisms of the CYP2B6 gene using the tetra-primer ARMS-PCR. Results:Results of this study revealed the significant association of rs3745274 GG (p < 0.001; OR = 0.027; 95% CI = 0.14-0.49) and GT (p < 0.001; OR = 4.04; 95% CI = 2.26-7.21) genotypes with the risk of addiction in methadone-responders. Also, a significant association between rs3745274 GG (p < 0.001; OR = 0.28; 95% CI = 0.15-0.51) and GT (p < 0.001; OR = 5.1; 95% CI = 2.8-5.28) genotypes and addiction relapse was found in methadone non-responders. Conclusion:Based on our findings, we can conclude that rs3745274 variant of CYP2B6 gene could serve as a potential biomarker, to evaluate the prognosis of addicted people fate under treatment with methadone. Key Words: Addiction, Biomarker, Methadone, Single-nucleotide polymorphism  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号