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   89篇
  免费   5篇
林业   9篇
农学   6篇
基础科学   1篇
  14篇
农作物   4篇
水产渔业   11篇
畜牧兽医   21篇
园艺   9篇
植物保护   19篇
  2023年   3篇
  2022年   3篇
  2021年   5篇
  2020年   8篇
  2019年   4篇
  2018年   6篇
  2017年   6篇
  2016年   7篇
  2015年   4篇
  2014年   9篇
  2013年   11篇
  2012年   5篇
  2011年   8篇
  2010年   4篇
  2009年   5篇
  2008年   2篇
  2006年   1篇
  1999年   1篇
  1998年   2篇
排序方式: 共有94条查询结果,搜索用时 468 毫秒
71.
Coprinus plicatilis, white rot fungi, capable of removing Reactive Orange 16 (Remazol Brillant Orange 3R) was immobilized in calcium alginate gel beads and used for decolorization of RO16 in aqueous in the Batch Shaking Bioreactor. The optimum conditions for immobilization of the microorganism, such as alginate and calcium ion concentration, initial cell amout, hardening time and bead size, were determined with a view to improving the RO16 removal rate. The characteristics of RO16 decolorization by immobilized fungal cells were investigated. The repeated use of immobilized cells for RO16 decolorization was performed and the results revealed that the bioactivity of immobilized cells was stable over 120 hours in the repeated batch cultivation RO16 removal. At the end of decolorization process, the metabolites of the dye decolorization produced by immobilized C. plicatilis, were analyzed via GC-MS. It was concluded that the removal of the dye by immobilized C. plicatilis was achieved.  相似文献   
72.
Foot-and-mouth disease (FMD) is one of the most devastating animal diseases, affecting all cloven-hoofed domestic and wild animal species. Previous studies from our group using DNA vaccines encoding FMD virus (FMDV) B and T cell epitopes targeted to antigen presenting cells, allowed demonstrating total protection from FMDV homologous challenge in those animals efficiently primed for both humoral and cellular specific responses (Borrego et al. Antivir Res 92:359-363, 2011). In this study, a new DNA vaccine prototype expected to induce stronger and cross-reactive immune responses against FMDV which was designed by making two main modifications: i) adding a new B-cell epitope from the O-serotype to the B and T-cell epitopes from the C-serotype and ii) using a dual promoter plasmid that allowed inserting a new cistron encoding the anti-apoptotic Bcl-xL gene under the control of the internal ribosomal entry site (IRES) of encephalomyocarditis virus aiming to increase and optimize the antigen presentation of the encoded FMDV epitopes after in vivo immunization. In vitro studies showed that Bcl-xL significantly prolonged the survival of DNA transfected cells (p?<?0.001). Accordingly, vaccination of Swiss out-bred mice with the dual promoter plasmid increased the total IgG responses induced against each of the FMDV epitopes however no significant differences observed between groups. The humoral immune response was polarized through IgG2a in all vaccination groups (p?<?0.05); except peptide T3A; in correspondence with the Th1-like response observed, a clear bias towards the induction of specific IFN-γ secreting CD4+ and CD8+ T cell responses was also observed, being significantly higher (p?<?0.05) in the group of mice immunized with the plasmid co-expressing Bcl-xL and the FMDV B and T cell epitopes.  相似文献   
73.
Fig tree mainly spread in regions where Mediterranean climate prevails can be grown over a wide range of soils without any significant deficiency or toxicity symptoms of plant nutrients. Surveys revealed that, however, quality is highly affected by nutrition especially N, K and Ca in fig production for commercial drying. This research work was initiated based on few studies performed on fertilization of fig. The experiment was performed between 2000 and 2002 in three fig orchards of cv. Sar?lop (syn. Calimyrna) in Ayd?n-Turkey. Trees received seven types of fertilization as (i) untreated control; (ii) NPK (430 g N, 200 g P2O5 and 430 g K2O per tree); (iii) NPK + 70 g Ca; (iv) NPK + 140 g Ca; (v) NPK + 280 g Ca; (vi) NPK + 420 g Ca and (vii) N + 420 g Ca, Ca(NO3)2 used as the Ca source. Tested fertilizer applications showed significant differences in respect to yield and quality of fig. Basic NPK fertilization with additional 280 g Ca treatment increased overall quality by reducing the number of fruit with ostiole-end crack and sunscald. Results showed that applied fertilizers exerted significantly in reduction of cull ratio and could alleviate the negative impact of yearly drought conditions.  相似文献   
74.
75.
Germplasm collections of C. reticulatum and C. echinospermum are limited, while both species face threats from over-grazing and habitat change in their natural environments. Recently many new accessions of C. reticulatum and C. echinospermum were collected in east and south-east Anatolia (Turkey) but they have not yet been evaluated for agro-morphological traits. Therefore, the current study investigated agro-morphological traits of new germplasm sources of C. reticulatum and C. echinospermum and evaluated resistance to biotic and abiotic stresses for chickpea improvement. The most attractive agro-morphological traits were canopy width, number of stems and pods per plant and biological yield. The most productive accessions of C. reticulatum and C. echinospermum had 712 and 625 pods per plant, respectively. Two distinct seed, flower and leaf shapes were found in accessions of C. echinospermum. Path analyses indicated that biological yield and harvest index had the most direct influence on seed yield in both species. Factor analyses showed that high seed yield in C. reticulatum depended on high biological yield and number of pods per plant, whereas high seed yield in C. echinospermum depended on harvest index. It was concluded that most accessions of C. reticulatum and C. echinospermum were not only resistant to some biotic and abiotic stresses but also had hidden alleles that could produce transgressive segregation in crosses to cultivated material.  相似文献   
76.
Investigations on soil and freshwater acidification are usually focused on well-aerated systems. This study deals with the role of reductive processes for the neutralization of acid soil solution within helocrene springs. Two toposequences consisting each of three profiles (forest soil, margin of fen, fen) were established to study the chemistry of the solid phase (soil pH, CEC, pedogenic Fe- and Al-oxides) and the soil solution in two small spring catchments on three dates during 1991 and 1992. Despite high acid inputs and acidified forest soils the pH of the spring outflow is near neutral, and the soil solid phases of the spring fens are not acidified. The results support the following hypothesis: Aluminum with its corresponding anion sulfate is leached with the soil solution into the water-saturated fens. Dissimilatory iron and sulfate reduction take place within the fen and generate alkalinity. Reduced iron either reacts with sulfide to form pyrite or migrates within the fen profile and precipitates in the uppermost, oxic horizons, consuming part of the generated alkalinity. Due to the higher pH values in the fens the incoming aluminum precipitates releasing acidity. The alkalinity generated exceeds the amount of acidity released by oxidation and precipitation of iron and the precipitation of aluminum. A balance of alkalinity consuming and alkalinity generating processes based on solid phases showed that iron and sulfate reduction can account for at least 67% of the neutralization of acidity entering the fen of one of the catchments. Due to shorter water retention times and higher discharge these processes are of minor importance in the other catchment.  相似文献   
77.
Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin content. This study was a part of the Project No. 62-02-001 TUBITAK-MAN-GMBAE named “Investigations on Biogenetically Develop Poplar Clones as a Raw Material for Pulp and Paper Industry” and financially supported by General Management of Turkish Pulp and Paper Mills.  相似文献   
78.
Abstract

This study was carried out to investigate the effects of individual versus combined housing systems on behavioural and growth responses of dairy calves in order to test the hypothesis that when calves were kept in early age individually and later in groups, they would increase growth performance and social behaviours. Twenty-four Holstein Friesian calves were allocated to two different housing systems. After three days of colostrum feeding, individually housed (IH) calves were kept in pens (1 m×1.5 m) for 60 days while combined housed (CH) calves were kept in group pens (3 m×3 m) for 30 days after individual housing during the period of 4–33 days. Each calf was monitored twice a week for a period of 1 h starting at 08.00, 10.00, 12.00, 18.00, 20.00 and 22.00 h at 10-min intervals. Behavioural activities were playing, walking, licking objects, idle standing, lying, restlessness, grooming and tongue playing. Calves’ live weights, body measurements and feed intakes were determined on a weekly basis. The results were: 1) combined housing calves increased their calf starter intake (37.35±1.24 kg vs. 23.39±0.86 kg; p<0.001), alfalfa hay intake (8.76±0.35 kg vs. 7.14±0.43 kg; p<0.05) and total feed intake (46.11±1.04 kg vs. 30.53±0.86 kg; p<0.001) compared to individual housed calves; 2) combined housing increased the proportional events of playing (12.80 vs. 2.86%), walking (19.14 vs. 3.81%) and grooming (8.06 vs. 4.60%), but decreased licking objects (1.03 vs. 2.94%), idle standing (20.73 vs. 36.29%), lying (30.19 vs. 39.53%) and restlessness (1.69 vs. 3.47%) compared to individual housing systems (p<0.001) without affecting tongue rolling (6.36 vs. 6.50%); 3) combined housing system increased body weight gain by about 2.36 kg and body length by about 1.48 cm per calf compared to those kept in individual pens (p<0.05). In conclusion, combined housing system provided calves more opportunity to show their walking, playing and grooming activities, reflecting increases in feed intake, body weight gain and length compared to individual housing system.  相似文献   
79.
Present study reported the variation in electrophoretic seed subfraction (albumins, globulin A, globulin B, glutelins) patterns in some Lathyrus species collected from their natural habitats different localities in Turkey. Electrophoretic data were documented by using a gel documentation system (Bio-Rad, USA) and analysed by using Quantity 1-D analysis software and also the dendograms were formed with 4.0% tolerance in UPGAMA (Unweighed Pair-Group Arithmetic Mean). The differences among species were observed and all seven species were clearly identifiable from the protein patterns. The dendograms obtained from cluster analysis of seed storage proteins data showed examined species have displayed a number of distinct relationships. According to our results, it seems justified to recommend a wider use of electrophoretic analysis of seed storage proteins in taxonomic investigations of leguminous plants.  相似文献   
80.
Abstract

This study aimed to assess the efficiencies of composts and vermicomposts obtained from two different composting methods on the growth, mineral nutrition and nutrient uptake of wheat. Composts and vermicomposts were applied to plastic pots under greenhouse condition with the application doses of 0, 5, 10, 20, and 40 t ha?1. The pot-experiment lasted three months. The results showed that plant dry weight increased with the increase in doses when compared to the control groups where no composts and vermicomposts were applied. However, no differences were found among the doses from 5 to 40 t ha?1 of composts and vermicomposts. Although application doses did not affect significantly on the most of the plant nutrient concentrations, Fe concentration in plant decreased with the increase in application doses. Additionally, no significant differences among the composts and vermicomposts on plant nutrient concentrations except for Mg were detected. Comparing to the control dose (0 t ha?1), nutrient uptakes by plant from the soil significantly increased with the increase of application doses, but no significant differences were determined amongst the doses of 5 and 40 t ha?1, generally. The effect of production methods on the most of investigated parameters including plant dry weight was similar.  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