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111.
Pedotransfer functions (PTFs) make use of routinely surveyed soil data to estimate soil properties but their application to soils different from those used for their development can yield inaccurate estimates. This investigation aimed at evaluating the water retention prediction accuracy of eight existing PTFs using a database of 217 Sicilian soils exploring 11 USDA textural classes. PTFs performance was assessed by root mean square differences (RMSD) and average differences (AD) between estimated and measured data. Extended Nonlinear Regression (ENR) technique was adopted to recalibrate or develop four new PTFs and Wind’s evaporation method was applied to validate the effectiveness of the relationships proposed. PTFs evaluation resulted in RMSD and AD values in the range 0.0630–0.0972 and 0.0021–0.0618 cm3 cm–3, respectively. Best and worst performances were obtained respectively by PTF-MI and PTF-ZW. ENR allowed to recalibrate PTF-MI and PTF-ZW with improvements of RMSD (0.0594 and 0.0508 cm3 cm–3) and to develop two relationships that improved RMSD by 75–78% as compared to PTF-MI. The results confirmed the potential of ENR technique in calibrating existing PTFs or developing new ones. Validation conducted with an independent dataset suggested that recalibrated/developed PTFs represent a viable alternative for water retention estimation of Sicilian soils.  相似文献   
112.
Journal of Soils and Sediments - The paper aims to show the preliminary monitoring and field test results of the innovative technology tested in the framework of the MARINAPLAN PLUS LIFE project...  相似文献   
113.
A 9-year-old neutered male domestic shorthair cat was presented because of coughing, dysphagia, and prostration. Examination revealed firm bilateral anterocervical swellings extensively adhered to the surrounding tissues. Anisocoria with left-side miosis was also evident. X-ray and ultrasound examinations along with a fine-needle aspiration biopsy were performed. Slides were stained with May-Grünwald Giemsa, and a diagnosis of salivary gland carcinoma was made. At surgery, the tumor was found to involve both submandibular salivary glands as well as adjacent lymph nodes and surrounding tissues. The cat was euthanized and necropsy was performed. The majority of tissues and organs examined histologically, including mandibular and retropharyngeal lymph nodes, soft palate, laryngopharynx and lungs, contained neoplastic cells whose appearance was consistent with adenocarcinoma. Bilateral salivary adenocarcinoma has not previously been reported in cats, and extensive metastases are rare.  相似文献   
114.
This study shows that a diet including insect-resistant Bt176 maize, fed to 53 ewes and their progeny for 3 years, did not have adverse effects on their health or performance and that no horizontal gene transfer to ruminal microorganisms or animal tissues was detected. No differences were observed regarding performance, reproductive traits, haematological parameters, antioxidant defences, lymphocyte proliferative capacity, phagocytosis and intracellular killing of macrophages, and ruminal microbial population characteristics between control and genetically modified (GM) maize-fed animals. Immune response to Salmonella abortus ovis vaccination was more efficient in GM maize fed sheep. No modifications of histological features of tissues were found; however, cytochemical analyses of ruminal epithelium by Ki67 staining provided evidence of proliferative activation of basal cells in all GM maize-fed ewes. Preliminary electron microscopy analyses of the liver and pancreas revealed smaller cell nuclei containing increased amounts of heterochromatin and perichromatin granules in GM maize-fed lambs. Meat protein content and water loss by cooking were slightly affected by the dietary treatment. No transgenic DNA was detected in tissues, blood, and ruminal fluid or ruminal bacteria. Longitudinal studies should be included in evaluation of food safety whenever possible and sheep may be a useful animal model for toxicological assessment.  相似文献   
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116.
Attempting to contribute to the development of a more objective morphological evaluation of dog spermatozoa, in this study the indices of multiple sperm defects (multiple abnormalities index [MAI]; teratozoospermic index [TZI]; sperm deformity index [SDI]) were calculated following the World Health Organization (WHO) guidelines. In Experiment I, the concordance of MAI, TZI and SDI with the proportions of morphologically normal spermatozoa (MNS) was evaluated in fresh ejaculated spermatozoa (dogs = 47). In Experiment II, the potential role of indices as prognostic values was assessed in spermatozoa of different origin and treatment (fresh ejaculated: n = 6; fresh epididymal: n = 6; frozen‐thawed ejaculated: n = 6) by their correlation with different semen parameters (motility, membrane integrity and acrosome status) and with an in vitro sperm function test. Samples with different proportions of MNS showed different values of SDI, the index that better represented the decline of sperm morphology in both fresh and frozen‐thawed samples (Exp. I and II; p < 0.05). No correlations between indices and semen parameters were observed (Exp. II), but when samples were evaluated collectively, negative correlations (SDI‐motility, p = 0.01; SDI‐acrosome integrity, p = 0.002) were found. Including all the defects of each spermatozoon, SDI might be a useful index during morphological analysis and better discriminates the increase in multiple defects. A more objective morphological evaluation for dog spermatozoa was achieved by the WHO method, and in vitro tests allowed to elucidate the validity of SDI as prognostic indicator of in vitro fertilizing potential.  相似文献   
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118.
Antarctic snowfall exhibits substantial variability over a range of time scales, with consequent impacts on global sea level and the mass balance of the ice sheets. To assess how snowfall has affected the thickness of the ice sheets in Antarctica and to provide an extended perspective, we derived a 50-year time series of snowfall accumulation over the continent by combining model simulations and observations primarily from ice cores. There has been no statistically significant change in snowfall since the 1950s, indicating that Antarctic precipitation is not mitigating global sea level rise as expected, despite recent winter warming of the overlying atmosphere.  相似文献   
119.
Dissimilatory iron-reducing bacteria play a fundamental role in catalysing the redox transformations that ultimately control the mobility of As in anoxic environments, a process also controlled by the presence of competing anions. In this study, we investigated the decoupling of As from loaded Al and Fe (hydr)oxides by competing anions in the presence of iron-reducing bacteria. Hematite, goethite, ferrihydrite, gibbsite and three aluminium-substituted goethites (AlGts) were synthesised and loaded with arsenate, followed by anaerobic incubation with different phosphate or carbonate-containing media in the presence of catalytic iron-reducing bacteria. Soluble Al, As, Fe and P contents were measured in aliquots by inductively coupled plasma optical emission spectrometry following periodical sampling. Shewanella putrefaciens cells were able to utilise both non-crystalline and crystalline Fe (hydr)oxides as electron acceptors, releasing Fe and As into solution. Phosphate and carbonate affected the Fe bioreduction, probably due to the precipitation of metastable mineral phases and also to phosphate-induced stabilisation on the hydroxide surfaces. Phosphate precipitation acted as a sink for As, thus limiting its mobilisation. The highest fraction of desorbed As by phosphate was observed for gibbsite, followed by AlGts. Similarly, gibbsite showed significant amounts of arsenate displaced by carbonate. In spite of its low crystallinity, ferrihydrite was the most efficient compound in retaining arsenate, possibly due to As co-precipitation. This study provides new insight into the management of As-contaminated soils and sediments containing Al-goethites and gibbsite, where the Fe activity may be too low to co-precipitate As-bearing vivianite. Thus, the dynamics of As(V) in flooded soils are significant in agriculture and environmental management.  相似文献   
120.
Invasive alien species cost forestry billions of euros every year and their early detection is becoming of utmost importance. The aim of this study is to improve some of the techniques available for trapping alien wood boring beetles (Scolytinae, Cerambycidae, and Buprestidae) arriving at high-risk sites, such as ports. During 2009–2011, trapping carried out in four Italian seaports tested the comparative efficiency of different luring (single-lure vs. multi-lure traps) and trap designs (cross-vane vs. multi-funnel). In addition, trap captures within the ports were compared with those obtained in surrounding areas. Six out of 49 species trapped in 3 years of investigation were of alien origin: four Scolytinae and two Cerambycidae. The number of species trapped in multi-lure traps was as high as that resulting from the sum of the single-lure traps. The two trap designs performed equally well, but multi-funnel traps were more robust and easier to use in ports. In 2011, the number of species trapped in ports and surrounding areas was similar, although differently distributed. On a total of 26 species trapped in this experiment, nine were exclusive to ports, of which three aliens, eight were exclusive to surrounding areas, of which one alien, and nine were common to both habitats, of which one alien. In conclusion, we suggest the use of multi-funnel traps baited with different lures for monitoring alien wood boring beetles in ports. Using traps outside the port is also recommended to validate the surveillance program.  相似文献   
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