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171.
The xerophytic shrub Ziziphus lotus (L) Lam may constitute the best choice as a fruit crop in arid regions and seems to have a great importance in uncultured and marginal soils. As the first report, this study investigates the genetic diversity among and within nine natural populations of Z. lotus encompassing wide range of ecological conditions in Algeria through analyses of fruits characteristics. Results reveal significant differences of fruit traits among and within populations; the morphological variability was significantly correlated with the variation of ecological conditions. In general, fruits color ranges from light to dark brown with mostly oval-shaped endocarps containing one or two seeds. In addition, fruits weight ranged between 0.43 and 0.75?g while length was comprised between 10 and 13?mm and fruit thickness varied between 9.85 and 12.81?mm. Overall, quantitative traits were significantly influenced by the environmental conditions, whereas qualitative traits were not clearly affected. Hence, three phenotypes were distinguished allowing detection of a gradual phenotypic variation following latitudinal gradient related mainly to aridity and sand content in the soil. Such variation offers a good basis for breeding objectives, principally for food and medicine objectives along with wide adaptations for various range of climate and soil. Management and conservation of Z. lotus germplasm in Algeria is highly recommended.  相似文献   
172.
A pot culture experiment was performed to study the effect of cadmium stress (Cd stress) on seedling growth, physiological traits, and remediation potency of Avena fatua, Lathyrus sativus, and Lolium temulentum. The seedlings of these native rangeland plant species were treated with 0, 2, 4, and 6 mM cadmium nitrate concentrations. Based on the results of analysis of variance (p < 0.05), the shoot height, shoot dry weight, root length, root dry weight, root: shoot ratio, total chlorophyll content, soluble sugars, and protein contentof A. fatua, L. sativus, and L. temulentum significantly decreased with increased cadmium concentrations. Generally, translocation factor (TF) and tolerance index (TI) decreased significantly as the concentration of cadmium increased. The maximum TF and TI of studied plants in various concentrations of Cd were observed in L. temulentum followed by L. sativus and A. fatua. The root concentration factor (RCF) values of all studied plants were higher than 1 under different cadmium concentrations. Our results indicate that Lolium temulentum could be labeled as an accumulator of Cd asthe values of TF and RCF are greater than 1. A. fatua and L. sativus showed a potential to be used in the phytoremediation of Cd-contaminated soils.  相似文献   
173.
The citrus cottony scale, Pulvinaria aurantii Cockerell, is the most important pest of citrus orchards in northern Iran in recent years. Owing to the harmful impacts of chemical insecticides, the use of biorational pesticides seems a safe and convenient way to control this pest. The present investigation was set up to study contact toxicity of various biorational and chemical compounds on the first, second instar nymph and overwintering adult of the citrus cottony scale, P. aurantii, and its predator, Cryptolaemus montrouzieri Mulsant under field conditions. The results indicated that the highest percentage of mortality of first instar nymph of the citrus cottony scale was observed in the Dayabon treatment of 9 and 10?ml/L, 100.0%?±?0.0% and the lowest percentage was observed in Palizin treatment of 1.5?ml/L, 34.7%?±?2.9%. In the second instar nymph, the highest mortality was seen in the Dursban treatment of 2?ml/L, 94.7%?±?2.4% and the lowest mortality in the Palizin treatment of 1.5?ml/L, 30.0%?±?2.3%. Also, for overwintering adults Dayabon 10?ml/L caused the highest mortality, 96.0%?±?4.0% during 24?h. In the case of ladybird insects, the highest and lowest percentage of mortality was observed in the Dursban treatment of 2?ml/L, 76.7%?±?8.8%, Dayabon 5?ml/L, and Palizin 2?ml/L, 3.3%?±?3.3%, respectively. The highest and lowest mortality rate of larvae of ladybird was estimated in the Dursban treatment of 2?ml/L, 83.3%?±?3.3% and Dayabon 5?ml/L, 3.3%?±?3.3%, respectively. Also, for overwintering predator adults Palizin 1.5?ml/L had the lowest mortality, 3.3%?±?3.3% during 24?h and this rate remain unchanged after 96?h after treatment. According to the results obtained, treatments with Dayabon 9 and 10?ml/L, can be a viable alternative to other high-risk chemical pesticides in addition to effectively controlling citrus cottony scale without having any adverse impacts on predator ladybird.  相似文献   
174.
The aim of this study was to assess the effect of increasing inclusion levels (100, 150, 200 and 300 g/kg) of rice bran protein concentrate (RBPC) in jundiá (Rhamdia quelen) diets using growth, body composition, somatic indices and digestive enzyme activity as parameters. Five isoproteic (370.08 ± 0.04 g/kg) and isocaloric (13.38 ± 0.04 MJ/kg) diets were formulated with four replicates per treatment. After acclimation, 500 jundiá juveniles (initial mean weight of 6.28 ± 0.12 g) were distributed into 20 round polyethylene tanks (280 L) (25 fish per tank) coupled to a thermoregulated water recirculating system. The fish were fed experimental diets three times daily (at 9:00, 13:00 and 17:00 hr) to apparent satiation. At the end of the trial (45 days), no significant differences were found in the body chemical composition, somatic indices, and trypsin and chymotrypsin enzymes of the fish fed experimental diets. A lower final weight and a lower condition factor were found in fish fed diets RBPC10 (100 g/kg of RBPC) and RBPC15 (150 g/kg of RBPC). Based on the results of this study, it is clear that the use of RBPC (at high dietary inclusion levels of 200 and 300 g kg?1) is an effective alternative protein source to fishmeal.  相似文献   
175.
It is necessary to identify the heat-tolerant cultivars of bedding plants in order to cope with the challenges of the global warming. The physiological and anatomical responses of four calendula cultivars (Candyman’, ‘Zen’, ‘Indian Prince’, and ‘Pacific Beauty’) to four duration levels (0, 7, 14 and 21 days) of heat stress (in a mean range of 35–42°C), were investigated after their establishment under greenhouse conditions. The results indicated that calendula cultivars displayed different responses to various heat duration levels in most parameters. Although the gas exchange of ‘Candyman’ was the highest in control treatment, it showed a considerable reduction in all levels of stress durations. In contrast, ‘Indian Prince’ maintained gas exchange and chlorophyll content and exhibited the most resistance to heat stress among others, especially for longer duration exposure, which might be resulted from the greater soluble sugar content, higher stomatal density, and thicker leaves. Experiment to assess cell membrane thermostability showed heat stress resulted in significant increase in electrolyte leakage percentage as the incubation temperature of all cultivars was increased. However, the least membrane stability was observed in ‘Zen’, indicating the higher sensitivity of this cultivar to heat-stress conditions in comparison to three other cultivars.  相似文献   
176.
Background:Glioblastoma multiforme is the most invasive and lethal form of brain cancer with unclear etiology. Our study aimed to investigate the molecular prevalence of HCMV and EBV infections in patients with GBM. Methods:This case-control study was conducted on 42 FFPE brain tumor samples from GBM patients and 42 brain autopsies from subjects without neurological disorders. The presence of EBV and HCMV DNA was determined, using PCR and nested-PCR assays, respectively. Results:HCMV DNA was detected in 3 out of 42 (7.1%) of GBM samples and was absent from the control group (p = 0.07). Importantly, EBV DNA was detected in 9 out of 42 (21.4%) brain tissue specimens of GBM subjects, but again in none of the control group (p = 0.001). Conclusion:Our findings indicate that infection with EBV is associated with GBM. Key Words: Brain tumor, Epstein-Barr virus, Glioblastoma, Human cytomegalovirus  相似文献   
177.
Journal of Soils and Sediments - Mining areas are low-quality habitats for macro- and microorganisms’ development, mainly due to the degradation of the soil quality by metal pollution. The...  相似文献   
178.
A novel thin film nanofibrous composite (TFNC) polyphenylsulfone (PPSU) membrane was fabricated by casting a thin PPSU barrier layer on the surface of the electrospun nanofibrous PPSU support. Polyethylene glycol (PEG) 400 was applied in the electrospinning solution to prevent the penetration of coating solution into the support. The membrane morphology and filtration performance were investigated via scanning electron microscopy (SEM), and filtration of canned beans production wastewater, respectively. Atomic force microscopy (AFM) was utilized to evaluate the surface roughness of the membranes. Furthermore, the mechanical strength and thermal stability of the membranes were determined via tensile test and thermogravimetric analysis (TGA). Comparison of the TFNC membrane and the unsupported membrane prepared through the wet phase inversion method with almost equal rejection values indicated a 2.3 fold higher PWF using the former.  相似文献   
179.
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