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71.
This study investigated the effect of bronchoscopy and bronchoalveolar lavage (BAL) on respiratory function, determined by barometric whole-body plethysmography (BWBP), of healthy and allergen-sensitized cats. Furthermore, the efficacy of inhaled bronchodilators in preventing changes in respiratory function was determined. For test 1, 18 healthy experimental cats were investigated on day 1 by BWBP. On day 2, the cats underwent BWBP after sedation (medetomidine), after anesthesia induction (propofol), and after bronchoscopy and BAL. Enhanced pause (Penh) was significantly increased after bronchoscopy and BAL (1.64 +/- 0.17 versus 1.23 +/- 0.07, P < .05). For test 2, 6 cats were sensitized to ovalbumin (OVA), 6 cats were sensitized to Ascaris suum (AS), and 6 cats served as controls. On day 0, OVA- and AS-sensitized cats underwent an inhaled allergen challenge, whereas controls were exposed to saline. On days 1 and 2, the same protocol as described for test 1 was repeated. Post-BAL Penh of the AS-sensitized cats was significantly higher than at test 1 (2.28 +/- 0.22 versus 1.69 +/- 0.33, P < .05) and was correlated with BAL fluid neutrophil count (r = 0.55, P < .05). During tests 3, 4, and 5, the same protocol as used for test 2 was applied to each cat group, with the animals being randomly treated before sedation with inhaled salbutamol (200 microg), ipratropium bromide (40 microg), or a combination of both (200 + 40 microg). Post-BAL Penh of the AS-sensitized group was significantly decreased after the salbutamol + ipratropium bromide treatment (1.56 +/- 0.18 versus 2.28 +/- 0.22, P < .05). This study suggests that bronchoscopy and BAL induce airflow limitation in cats, which is more severe in the presence of lower airway inflammation. Inhaled salbutamol + ipratropium bromide reduce BAL-induced bronchoconstriction in AS-challenged cats and might be recommended as preventive treatment of asthmatic cats undergoing bronchoscopy.  相似文献   
72.
In Southeast Asia, traditional poultry marketing chains have been threatened by epidemics caused by the highly pathogenic avian influenza H5N1 (HPAI H5N1) virus. In Thailand, the trade of live backyard chickens is based on the activities of traders buying chickens from villages and supplying urban markets with chicken meat. This study aims to quantify the flows of chickens traded during a 1-year period in a province of Thailand. A compartmental stochastic dynamic model was constructed to illustrate trade flows of live chickens from villages to slaughterhouses. Live poultry movements present important temporal variations with increased activities during the 15 days preceding the Chinese New Year and, to a lesser extent, other festivals (Qingming Festival, Thai New Year, Hungry Ghost Festival, and International New Year). The average distance of poultry movements ranges from 4 to 25 km, defining a spatial scale for the risk of avian influenza that spread through traditional poultry marketing chains. Some characteristics of traditional poultry networks in Thailand, such as overlapping chicken supply zones, may facilitate disease diffusion over longer distances through combined expansion and relocation processes. This information may be of use in tailoring avian influenza and other emerging infectious poultry disease surveillance and control programs provided that the cost-effectiveness of such scenarios is also evaluated in further studies.  相似文献   
73.
Sinonasal aspergillosis is a frequent cause of nasal discharge that occurs in otherwise healthy, young to middle-aged dogs. A local immune dysfunction is suspected in affected animals, and the role of increased interleukin-10 mRNA expression in the nasal mucosa of affected dogs is currently under investigation. Despite recent advances in imaging techniques, the "gold standard" for diagnosing the disease is direct visualization of fungal plaques during endoscopy or observation of fungal elements on cytology or histopathologic examination. Treatment can be challenging; however, the use of topical enilconazole or clotrimazole through noninvasive techniques has increased the success of treatment and decreased the morbidity and duration of hospitalization.  相似文献   
74.
The aim of this study was to develop sustained release microspheres of capsicum oleoresin as an alternative to in-feed additives. Two spray-cooling technologies, a fluidized air bed using a spray nozzle system and a vibrating nozzle system placed on top of a cooling tower, were used to microencapsulate 20% of capsicum oleoresin in a hydrogenated, rapeseed oil matrix. Microencapsulation was intended to reduce the irritating effect of capsicum oleoresin and to control its release kinetics during consumption by the animal. Particles produced by the fluidized air bed process (batch F1) ranged from 180 to 1,000 microm in size. The impact of particle size on release of capsaicin, the main active compound of capsicum oleoresin, was studied after sieving batch F1 to obtain 4 formulations: F1a (180 to 250 microm), F1b (250 to 500 microm), F1c (500 to 710 microm), and F1d (710 to 1,000 microm). The vibrating nozzle system can produce a monodispersive particle size distribution. In this study, particles of 500 to 710 microm were made (batch F2). The release kinetics of the formulations was estimated in a flow-through cell dissolution apparatus (CFC). The time to achieve a 90% dissolution value (T90%) of capsaicin for subbatches of F1 increased with the increase in particle size (P < 0.05), with the greatest value of 165.5 +/- 13.2 min for F1d. The kinetics of dissolution of F2 was slower than all F1 subbatches, with a T90% of 422.7 +/- 30.0 min. Nevertheless, because CFC systems are ill suited for experiments with solid feed and thus limit their predictive values, follow-up studies were performed on F1c and F2 using an in vitro dynamic model that simulated more closely the digestive environment. For both formulations a lower quantity of capsaicin dialyzed was recorded under fed condition vs. fasting condition with 46.9% +/- 1.0 vs. 74.7% +/- 2.7 for F1c and 32.4% +/- 1.4 vs. 44.2% +/- 2.6 for F2, respectively. This suggests a possible interaction between capsaicin and the feed matrix. Moreover, 40.4 +/- 3.9% of the total capsaicin intake in F2 form was dialyzed after 8 h of digestion when feed had been granulated vs. 32.4 +/- 1.4% when feed had not been granulated, which suggests that the feed granulation process could lead to a partial degradation of the microspheres and to a limitation of the sustained release effect. This study demonstrates the potential and the limitations of spray-cooling technology to encapsulate feed additives.  相似文献   
75.
Journal of Soils and Sediments - In urban areas, soil functions are deeply impacted by all human activities, e.g., water infiltration, carbon storage, and chemical substances degradation potential....  相似文献   
76.
Rice genes OsDjA2 and OsERF104, encoding a chaperone protein and an APETELA2/ ethylene-responsive factor, respectively, are strongly induced in a compatible interaction with blast fungus, and also have function in plant susceptibility validated through gene silencing. Here, we reported the CRISPR/Cas9 knockout of OsDjA2 and OsERF104 genes resulting in considerable improvement of blast resistance. A total of 15 OsDjA2 (62.5%) and 17 OsERF104 (70.8%) T0 transformed lines were identified from 24 regenerated plants for each target and used in downstream experiments. Phenotyping of homozygous T1 mutant lines revealed not only a significant decrease in the number of blast lesions but also a reduction in the percentage of diseased leaf area, compared with the infected control plants. Our results supported CRISPR/Cas9-mediated target mutation in rice susceptibility genes as a potential and alternative breeding strategy for building resistance to blast disease.  相似文献   
77.
Melampsora medusae is a quarantine fungus in the European Union (EU) that causes a damaging leaf rust disease on poplars. Two formae speciales of the pathogen can be distinguished, M. medusae f. sp. deltoidae and M. medusae f. sp. tremuloidae, but the EU plant health directive 2000/29/EC currently in force does not make the distinction between them. EU countries must have the ability to detect and identify rapidly the introduction of these quarantine fungi and to conduct extensive surveys in case of outbreaks. Efficient detection tools are thus needed. In this study, a sensitive real-time PCR assay was developed to detect the presence of M. medusae in poplar leaf samples. A unique primer/hydrolysis probe combination targeting both formae speciales was designed using species-specific polymorphisms observed within the internal transcribed spacer region. An additional primer/hydrolysis probe combination was designed from a region of the 28S rDNA that is highly conserved in the genus Melampsora and used in a separate real-time PCR assay in order to check the quality of the DNA extracted from Melampsora urediniospores. The test developed demonstrated a high sensitivity since it enables the reproducible detection of two M. medusae urediniospore in a mixture of 2 mg of urediniospores (ca 800 000 urediniospores) of other Melampsora species. This new real-time PCR tool should be useful for laboratories in charge of official analyses since it has many advantages over the techniques currently used to monitor this quarantine pathogen in Europe.  相似文献   
78.
Secondary plants may be added to a cropping system for the purpose of improving pest control. In a recent article (Parolin P, Bresch C, Brun R, Bout A, Boll R, Desneux N, Poncet C (2012) Secondary plants used in biological control: a review, International Journal of Pest Management 58, 91–100) we defined different categories of secondary plants used to enhance biological control: companion, repellent, barrier, indicator, trap, insectary, and banker plants are intentionally added to agricultural systems in order to improve pest management through either top-down or bottom-up processes. In the present paper, we focus on the functional characteristics of secondary plants and on the mechanisms which contribute to reducing the presence of pests. If we understand and integrate the effects that such plants have on pests and beneficial arthropods, together with the multitrophic interactions in which these organisms are involved, the application of pesticides in crop systems can be reduced and enhanced productivity in agro-ecosystems achieved. Here, we identify the main characteristics of, and the prerequisites for, plants which can enhance crop protection in agro-ecosystems.  相似文献   
79.
This study compared the metabolic fate of [(14)C]-DCP, [(14)C]-residues from radish plants, and purified [(14)C]-DCP-(acetyl)glucose following oral administration in rats. A rapid excretion of radioactivity in urine occurred for [(14)C]-DCP, [(14)C]-DCP-(acetyl)glucose, and soluble residues, 69, 85, and 69% within 48 h, respectively. Radio-HPLC profiles of 0-24 h urine from rats fed [(14)C]-DCP and [(14)C]-DCP-(acetyl)glucose were close and qualitatively similar to those obtained from plant residues. No trace of native plant residues was detected under the study conditions. The structures of the two major peaks were identified by MS as the glucuronide and the sulfate conjugates of DCP. The characterization of a dehydrated glucuronide conjugate by MS and NMR of DCP was unusual. In contrast to soluble residues, bound residues were mainly excreted in feces, 90% within 48 h, whereas total residues were eliminated in both urine and feces. For total residues, the radioactivity in feces was higher than expected from the percentage of soluble and bound residues in radish plants. This result highlighted that less absorption took place when residues were present in the plant matrix as compared to plant-free residues and DCP.  相似文献   
80.
Chemical investigation of the South-Pacific marine sponge Suberea clavata led to the isolation of eight new bromotyrosine metabolites named subereins 1–8 (2–9) along with twelve known co-isolated congeners. The detailed configuration determination of the first representative major compound of this family 11-epi-fistularin-3 (11R,17S) (1) is described. Their chemical characterization was achieved by HRMS and integrated 1D and 2D NMR (nuclear magnetic resonance) spectroscopic studies and extensive comparison with literature data. For the first time, a complete assignment of the absolute configurations for stereogenic centers C-11/17 of the known members (11R,17S) 11-epi-fistularin-3 (1) and 17-deoxyfistularin-3 (10) was determined by a combination of chemical modifications, Mosher’s technology, and ECD spectroscopy. Consequently, the absolute configurations of all our new isolated compounds 2–9 were determined by the combination of NMR, Mosher’s method, ECD comparison, and chemical modifications. Interestingly, compounds 2–7 were obtained by chemical transformation of the major compound 11-epi-fistularin-3 (1). Evaluation for acetylcholinesterase inhibition (AChE), DNA methyltransferase 1 (DNMT1) modulating activity and antifouling activities using marine bacterial strains are also presented.  相似文献   
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