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51.
Further data on the morphology (the lip region characters) and phylogeny of the genus Sakia are presented. The new observations were based on scanning electron microscopy (SEM) and light microscopy (LM). A new species, Sakia sisanganensis n. sp., was recovered from rotten wood of a dead beech tree (Fagus orientalis) in northern Iran, herein described and illustrated based on an integrative approach, that is morphological, morphometric and molecular characters. The new species is characterized by a combination of the following features: fine transverse striae and vestigial single band in the lateral field in SEM. Labial area dorso‐ventrally flattened. Oral region with two concentric hexagonal plates, the inner one apparently elevated. Amphidial openings short, slit‐like. Stylet delicate. Median bulb fusiform to spindle‐shaped with weak valvular apparatus. Spermatheca functional. Tail filiform with faintly pointed tip and males common. The new species was morphologically compared with four known species of the genus, viz., S. alii, S. arboris, S. castori and S. indica, all having indistinct lateral fields. Molecular phylogenetic analyses were performed based on the small subunit ribosomal RNA gene (SSU rDNA). In the Bayesian inference (BI), S. sisanganensis n. sp. with two isolates was strongly supported as a sister taxon of a clade harbouring S. arboris + Lelenchus species. However, in the maximum likelihood (ML) analysis, the new species formed a clade with S. arboris, thus supporting the reciprocal monophyly of the genera Sakia and Lelenchus. Accordingly, the test of monophyly was performed (using Bayes factor) and the results did not reject the monophyly of sakia (i.e., S. sisanganensis n. sp. and S. arboris as sister taxa) based on the currently available data.  相似文献   
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Abstract

In order to evaluate the effects of water deficit stress and foliar application of zinc (Zn) and iron (Fe) nanoparticles on physiological characters and seed yield of pinto bean, an experiment was designed as a split factorial design based on randomized complete blocks with three replications in two growing seasons (2016–2017 and 2017–2018). Treatments were included water deficit stress (normal irrigation and water deficit stress in 50% flowering), foliar application of nano-fertilizers (control, nano-Zn (1.5?g L?1), nano-Fe (2?g L?1) and combination of nano-Zn and nano-Fe) and four cultivars of pinto bean (Sadri, Coosha, Cos16, and Ghaffar). The results showed that the soluble sugars and proline content was increased under water deficit. Water deficit stress through decreasing chlorophyll and relative water content of leaves as well as the iron and zinc content of seeds, decreased seed yield and quality. The application of nano-fertilizers of zinc and iron enhanced antioxidant enzymes activity, proline and soluble sugars content as well as leaf area. Also applied nano-fertilizers improved seed quality in terms of protein content. According to obtained results the effect of foliar spray of nano-fertilizers on iron and zinc content of seeds regards to bean cultivars was different. It was concluded that the foliar application of iron combined zinc nano-fertilizers can be useful in pinto bean cultivars under water deficit stress. In both normal and water deficit Cos16 cultivar showed the better amount of studied characteristics compared to other cultivars. The results of cluster analysis of these cultivars confirmed the superiority of Cos16 cultivar.  相似文献   
54.
Biofloc technology is considered as a method that degrades organic waste by microorganisms and produces microbial flocs. A 30-day experiment was performed to investigate the effects of partial replacement of daily feeding intake with biofloc on the growth performances, digestive enzymes activity and liver histology of the common carp Cyprinus carpio L. fingerlings. Two hundred and eight healthy fingerlings (58.6 ± 0.2 g) were randomly distributed in 12 tanks (30 L) at a density of 25.4 kg m?3 and fed experimental treatments (100 % daily feeding rate as a control, biofloc + 75 % daily feeding rate, biofloc + 50 % daily feeding rate, biofloc + 25 % daily feeding rate). At the end of experiment, the results indicated that the highest weight gain was observed in the fish fed BFT 75 % and control which differed significantly from those fed BFT 25 % (P < 0.05). Diet BFT 75 % improved total protease and pepsin activity compared with BFT 25 and 50 % (P > 0.05). No significant difference was observed in case of lipase, amylase and alkaline phosphatase activity between the treatments. In the liver, histological alterations were found in the treatments, and feeding the fish with BFT 75 % significantly improved hepatocellular quantification and qualification than the other groups. The results obtained in this experiment suggest that the biofloc improves growth performances, digestive enzyme activity and liver condition of the common carp fingerlings when 25 % of daily feeding rate (BFT 75 %) was replaced with one carbohydrate such as molasses in zero-water exchange system.  相似文献   
55.
The effectiveness of common carp pituitary extract (CPE), luteinizing hormone releasing hormone analogue (LHRH‐A2) injections and LHRH‐A2 implants for spawning induction in female sturgeon, Huso huso was examined. In the first trial, fish were injected with 7% physiological saline (control), 50 mg kg?1 CPE or LHRH‐A2 at 3.5, 7, 8 or 10 μg kg?1. In the second trial, fish were treated with LHRH‐A2 cholesterol pellet implants containing 0, 3.5, 7, 8 and 10 μg kg?1 LHRH‐A2. Ovulated eggs were removed using a minimally invasive surgical technique and were artificially fertilized. Injection of CPE and LHRH‐A2 at doses of 3.5, 7, 8 and 10 μg kg?1 resulted in the number of ovulated fish more than LHRH‐A2 implants (similar doses) or controls, although there was no significant difference at doses of 8 and 10 μg kg?1 (P ≥ 0.05). The latency period of fish receiving CPE and LHRH‐A2 injections was approximately 20 h, which was significantly lower than in fish receiving LHRH‐A2 implants (P ≤ 0.05). Furthermore, there were no significant differences in rates of fertilization or hatching among the progeny produced in any of the treatment groups (P ≥ 0.05). In conclusion, the data from this study could be useful for artificial propagation of not‐fully‐matured females of H. huso at sturgeon hatcheries.  相似文献   
56.
Over the past few decades, the usage of oxytetracycline(OTC), a kind of antibiotic, has increased with the development of aquaculture and livestock breeding. However, about 30–90% of the applied antibiotics are excreted as the parent compounds into the environment, especially with the application of animal manure to agricultural fields. This large influx of antibiotics may lead to the destruction of the natural microbial ecological community and pose great threats to human beings through the food chain. Therefore, the fate and toxicity of OTC in the environment are issues of great concern. Degradation of OTC, including the non-biodegradation and biodegradation, and the biological toxicity of its degradation products or metabolites, are reviewed in this paper. The non-biodegradation pathways include hydroxylation, quinonization, demethylation, decarbonylation, dehydration and secondary alcohol oxidation. Light(particularly UV light), pH and oxidizing substances play important roles in non-biodegradation. Biodegradation products include 4-epi-OTC(EOTC), 2-acetyl-2-decarboxy-amido-OTC(ADOTC), α-apo-OTC and β-apo-OTC. EOTC is an epimer and identied except for the configuration of the C4 dimethylamino group of OTC. Temperature and pH are the main factors affecting biodegradation pathways of OTC. In addition, this review discusses concerns over the biological toxicity of OTC degradation products.  相似文献   
57.
A feeding trial was conducted to evaluate the effects of moderate dietary concentrations of deoxynivalenol (DON) during a 21-day feeding experiment on the performance of broilers. Fifteen 1-day-old broiler chicks were randomly divided into two groups. The control group was fed non-contaminated diet. Another group of broilers was fed a diet naturally contaminated with 5 mg DON/kg diet. Deoxynivalenol had no effect (p > 0.05) on feed consumption, feed conversion, body-weight gain, live body weight or mortality. The absolute and relative weight of the organs (gizzard, pancreas, heart, spleen, colon and caecum) were not altered by the dietary inclusion of DON contaminated grain. However, both the absolute and relative weight of small intestine was decreased (p < 0.01) in DON fed broilers compared to the controls. No gross lesions were detected in any of the organs of birds fed contaminated wheat during the feeding trial. The microscopic examination revealed that, the height and the width of villi in duodenum decreased (p < 0.05) in birds fed DON contaminated wheat compared to controls. On the other hand the height and the width of jejunum villi were not affected (p > 0.05). This study indicates that feeding DON for 21 days to broiler chickens at a concentration of up to 5 mg/kg of diet influenced the weight of the small intestine as well as intestinal histology, especially the duodenum, as evidenced by shorter and thinner villi. In conclusion, diets with DON contamination below levels that induce negative impact on health and performance could affect small intestinal morphology in broilers.  相似文献   
58.
In January 2011, symptomatic chickpea and faba bean plants were observed in fields located in the Gezira state (Sudan). Faba bean plants showed yellowing and stunting, whereas chickpea plants presented yellowing, reddening and little leaves. The disease etiology was investigated using nested polymerase chain reaction (PCR) with phytoplasma-specific primers which amplify a fragment of the 16S rRNA gene. Sequencing and restriction fragment length polymorphism (RFLP) analyses revealed that the tested phytoplasmas belonged to the group 16SrII. Phylogenetic analyses of the 16S rRNA gene of the obtained sequences indicated that the chickpea and faba bean phytoplasmas from Sudan were more closely related to the phytoplasmas subgroup 16SrII-D. To our knowledge, this is the first report of phytoplasmas from the group 16SrII-D infecting chickpea in Sudan, and faba bean worldwide.  相似文献   
59.
The objective of this study was to investigate how weight-loss program would alter the proteome of the serum of Beagle dogs. For this purpose, serum samples from 5 Beagle dogs, before and after weight loss, were analyzed using 2-dimensional electrophoresis. Protein profiles of all samples were obtained, divided into 2 classes (obese and lean), and compared using specific 2-dimensional software, giving a total of 144 spot matches. Statistical analysis revealed 3 spot matches whose expressions were modulated in response to weight loss: 2 protein spots were upregulated and 1 protein spot was downregulated in the obese state in comparison with the lean state of the dogs. Mass spectrometric identification of differentially regulated spots revealed that these protein spots corresponded to retinol-binding protein 4, clusterin precursor, and α-1 antitrypsin, respectively, which could be considered potential markers of obesity and obesity-related disease processes in dogs.  相似文献   
60.
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