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   216篇
  免费   14篇
  国内免费   1篇
  2023年   5篇
  2022年   8篇
  2021年   21篇
  2020年   4篇
  2019年   17篇
  2018年   10篇
  2017年   5篇
  2016年   11篇
  2015年   18篇
  2014年   12篇
  2013年   17篇
  2012年   18篇
  2011年   10篇
  2010年   9篇
  2009年   6篇
  2008年   5篇
  2007年   7篇
  2006年   9篇
  2005年   7篇
  2004年   4篇
  2003年   2篇
  2002年   2篇
  2001年   5篇
  2000年   1篇
  1995年   1篇
  1993年   1篇
  1992年   3篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1987年   1篇
  1985年   1篇
  1984年   1篇
  1982年   1篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1971年   1篇
排序方式: 共有231条查询结果,搜索用时 15 毫秒
211.
Journal of Plant Growth Regulation - Nanotechnology now plays a revolutionary role in many applications; nanomaterials have experienced significant importance in both basic and applied sciences as...  相似文献   
212.
The effect of fertilizer on yield and yield related traits studied in two consecutive years at two different locations. Three different doses of fertilizer (NPK) applied at the rate of 9:23:0, 18:46:12 and 27:69:25 respectively on sixteen chickpea, genotypes (Desi and Kabuli advance lines and commercial varieties). Data recorded for days to 50% flowering, plant height, primary and secondary branches, pods per plant, 100-grain weight and grain yield (kg/ha). In Desi chickpea highest grain yield (kg/ha) in both years was produced by advance line D-12026 and in Kabuli advance line K-70005 at Faisalabad location. Grain yield kg/ha had significant positive correlation with all the considered parameters except days to 50% flowering and days to 50% maturity. The treatment comparison manifested that fertilizer doses 9:23:0 enhanced grain yield. The high dose of fertilizer is not recommendable. The grain yield of Desi and Kabuli chickpea at two locations Pulses Research Institute (PRI) Faisalabad and GBRSS (Gram Breeding Research Sub Station) Kallurkot had significant variation. The grain yield (kg ha−1) was significant high in research area of PRI, Faisalabad in both years. The NPK 9:23:0 found operative dose of fertilizer for chickpea.  相似文献   
213.
Inadequate plant stand establishment due to insufficient germination is an important bottleneck in achieving the potential yields, specifically under uncertain growing conditions. Hydropriming has been publicized as a useful tool to alleviate the stress-induced consequences. Association of DNA biosynthesis in hydroprimed seeds of maize; hybrid, PEHM 5 and its parental lines (CM150 and CM151) was studied. Seeds were hydroprimed at 25 °C for 30 h and half of them were surface dried while the other half were redried back to the original moisture contents. The treated and untreated seeds were evaluated for; germination test, mean germination time, vigour index and DNA levels in embryos of fully matured seeds. Both the treatment strategies significantly enhanced the planting value of maize seeds. Vigour index I revealed significant correlation with G2/G1 ratio whereas significant negative correlation between G2/G1 ratio and mean germination time was observed. Large amounts of 2C DNA signals in flow cytometric analysis divulged that most cells might had arrested in the cell cycle at the pre synthetic G1 phase of nuclear division. Augmentation of 4C signal in the embryonic region was noticed after imbibition that could be ascribed to cells entering the synthetic phase of nuclear division. The embryonic cells showed increased 4C:2C ratios after 30 h of imbibition. Apparently, DNA synthesis preceded germination. In dry seeds, DNA histograms revealed both a 2C signal and a considerable 4C peak. A priming period of 30 h in distilled water considerably enhanced the rate and uniformity of germination in both surface dried and redried treatment strategies. Upon priming, the ratio of 4C:2C increased during the 30 h priming period, though the level in case of redried seeds did not reach the level obtained after hydration in water without drying back. However, the 4C: 2C ratio was constant after redrying the seeds to the original moisture content, indicating that the chromosomal material in the embryonic cells had stably ceased cell cycle activity at the G2 phase. The present results indicate that the beneficial effects of priming on seedling performance could be associated with the action of replicative DNA synthesis processes prior to germination.  相似文献   
214.
215.
Auxins (Aux) are primary growth regulators that regulate almost every aspect of growth and development in plants. It plays a vital role in various plant processes besides controlling the key aspects of cell division, cell expansion, and cell differentiation. Considering the significance of Aux, and its potential applications, a study was conducted to observe the impact of indole acetic acid (IAA), a most active and abundant form of Aux on Brassica juncea plants growing under natural environmental conditions. Different concentrations (0, 10−10, 10−8, 10−6 M) of IAA were applied once in a day at 25-day stage of growth for 5 days, consecutively. Various parameters (growth, photosynthetic, biochemical, oxidative biomarkers and nutrient composition) were assessed at different days after sowing (DAS). Scanning electron microscopy (SEM) of leaf stomata, reactive oxygen species (ROS) localization in leaf and roots, and confocal microscopy were also conducted. The results revealed that all the IAA concentrations were effective in growth promotion and ROS reduction, however, the 10−8 M of IAA exhibited the maximum improvement in all the above mentioned parameters as compared to the control.  相似文献   
216.
Deregulation of the protein secretory pathway (PSP) is linked to many hallmarks of cancer, such as promoting tissue invasion and modulating cell-cell signaling. The collection of secreted proteins processed by the PSP, known as the secretome, is often studied due to its potential as a reservoir of tumor biomarkers. However, there has been less focus on the protein components of the secretory machinery itself. We therefore investigated the expression changes in secretory pathway components across many different cancer types. Specifically, we implemented a dual approach involving differential expression analysis and machine learning to identify PSP genes whose expression was associated with key tumor characteristics: mutation of p53, cancer status, and tumor stage. Eight different machine learning algorithms were included in the analysis to enable comparison between methods and to focus on signals that were robust to algorithm type. The machine learning approach was validated by identifying PSP genes known to be regulated by p53, and even outperformed the differential expression analysis approach. Among the different analysis methods and cancer types, the kinesin family members KIF20A and KIF23 were consistently among the top genes associated with malignant transformation or tumor stage. However, unlike most cancer types which exhibited elevated KIF20A expression that remained relatively constant across tumor stages, renal carcinomas displayed a more gradual increase that continued with increasing disease severity. Collectively, our study demonstrates the complementary nature of a combined differential expression and machine learning approach for analyzing gene expression data, and highlights key PSP components relevant to features of tumor pathophysiology that may constitute potential therapeutic targets.  相似文献   
217.
Abstract

Plant growth stimulating bacteria are very effective in immobilization of metals and reducing their translocation in plants through precipitation, and adsorption. A pot experiment was conducted to investigate the effectiveness of chitosan- and hematite-modified biochar and bacterial inoculations on the immobilization of nickel (Ni) in polluted soil under wheat cultivation. Application of modified biochars and inoculation with Pseudomonas putida significantly increased both wheat root and shoot dry matter yields but decreased Ni phytoextraction efficiency. The Ni concentration, translocation factor and uptake in wheat shoot and root significantly decreased the application of either modified or unmodified biochars. Bacterial inoculation significantly decreased mean translocation factor and also root and shoot concentration and the uptake Ni in the shoot. Chitosan-modified biochar was the most influential treatment in decreasing Ni uptake by wheat followed by P. putida inoculation treatment. The results demonstrated positive effects of chitosan modified biochar and inoculation with P. putida in increasing dry matter yield and decreasing Ni uptake in wheat grown on Ni-contaminated soil. According to the results of present study, modified biochars application and bacterial inoculation are influential treatments which prevent Ni toxicity probably.  相似文献   
218.
The removal of microbial and physico-chemical contaminants was investigated using an innovative biosand filter (BSF) containing three combinations of coniferous pinus bark biomass (CPBB), i.e. 1 cm (treatment 2), 2.5 cm (treatment 3) and 5 cm (treatment 4). The efficiency of BSF was assessed in batch mode experiments and the comparative reductions of contaminants were monitored over the control treatment (1) at temperature range of 1-15 °C for 90 days. Standard methods were used to analyze 9 operating, physico-chemicals and biological water quality parameters of pre-and post-water filtration samples after 15 days interval. The results showed mean 93 ± 2% and 95 ± 3% reductions of Eischerichia coli and total coliforms, respectively, for BSF containing the highest depth of CPBB (5 cm), whereby 100% removal was observed during the treatment time T30 to T45 days. The general affinity sequence for E. coli, total coliforms and turbidity removal in the four treatments was: BSF with 5 cm CPBB > BSF with 2.5 cm CPBB > BSF with 1 cm CPBB > Control. It was concluded that modified BSF with additional adsorbent of locally available CPBB is a very good decentralized treatment option for drinking water.  相似文献   
219.
In Vitro Cellular & Developmental Biology - Plant - Galega officinalis L. is known for its dominant secondary metabolite “galegine” a guanidine derivative used in the synthesis of...  相似文献   
220.
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