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The short introduction gives a review on the complex of exogen and endogen opioids and their receptors as well as on their pharmacodynamics, pharmacokinetics and toxicity of naloxone. The clinical efficacy of naloxone as an opioid antagonist is described. Applications of naloxone for the dog are specified: antagonisation of etorphine, morphine, levomethadone and fentanyl, antagonisation of exogen and endogen opioids in puppies and treatment of lactomania in the bitch. The mean effective dose to antagonize morphines is 0.003 mg/kg bodyweight. If persisting analgesia is indicated the dose of naloxone in titrating steps in 0.001 mg/kg bw. To antagonize postpartal hypoxia in puppies 0.02 mg per animal naloxone have to be injected. For treatment of lactomania a dose of 0.01 mg/kg bodyweight twice a day for a couple of days is recommended. The clinical effectivity of naloxone is proved doubtlessly. Compatibility and safety are very high.  相似文献   
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An ideal national resistance monitoring program should deliver a precise estimate of the resistance situation for a given combination of bacteria and antimicrobial at a low cost. To achieve this, decisions need to be made on the number of samples to be collected at each of different possible sampling points. Existing methods of sample size calculation can not be used to solve this problem, because sampling decisions do not only depend on the prevalence of resistance and sensitivity and specificity of resistance testing, but also on the prevalence of the bacteria, and test characteristics of isolation of these bacteria. Our aim was to develop a stochastic simulation model that optimized a national resistance monitoring program, taking multi-stage sampling, imperfect sensitivity and specificity of diagnostic tests, and cost-effectiveness considerations into account. The process of resistance testing of Campylobacter spp. isolated from cloacal swab samples from poultry was modeled using a Markov Chain Monte Carlo model. Different sampling scenarios on the number of flocks to be tested, the number of birds from each flock, and the number of campylobacter colonies submitted to susceptibility testing were evaluated regarding the precision of the resulting prevalence estimate. Precision of the prevalence estimate was defined as the absolute difference between apparent and true prevalence of resistance. A partial budget approach was utilized to find the most cost-effective combination of samples to obtain a defined precision of the prevalence estimate. For a sampling scenario testing 100 flocks, five birds per flock, and one campylobacter colony per sample, the median error of the prevalence estimate was 2.5%, and 95% of the simulations resulted in an error of 7% or less. When the total number of samples was kept constant, maximizing the number of flocks tested, and only testing one bird per flock resulted in the most precise prevalence estimate. Submitting more than one campylobacter colony to resistance testing did not improve the prevalence estimate. Partial budget analysis indicated that the most cost-effective strategy was testing of two birds per flock, and submitting one colony per sample to resistance testing.  相似文献   
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OBJECTIVE: Evaluation of the LMA-ProSeal for positive pressure ventilation (PPV) in the pig. STUDY DESIGN: Prospective observational study. ANIMALS: Twelve German country pigs, weighing 25-62 kg. METHOD: Lungs of pigs were mechanically ventilated under general anaesthesia using the LMA-ProSeal. The ease of insertion, number of attempts and total time until placement of the LMA-ProSeal and gastric tube were recorded. Bronchoscopy was performed to determine the position of the LMA-ProSeal and to detect signs of aspiration. Ventilation variables and the leak airway pressure (P(leak)) were measured. An arterial blood gas sample was taken to determine the adequacy of ventilation. RESULTS: The airway was secured in all pigs within 39 +/- 19 seconds (27-51). Different sizes of LMA-ProSeal were used; up to 30 kg: size 3, up to 43 kg: size 4; and above 43 kg: size 5. In all but one animal the P-LMA and gastric tube were inserted at the first attempt. In nine animals gastric fluid was drained through the gastric tube. There was no evidence of aspiration in any animal. The mean [+/-SD (95%CI)]P(leak) was 28.8 +/- 7.5 cm H(2)O (24.06-33.60) and normal ventilation was achieved in all animals. CONCLUSIONS: The results of this study indicate that the airway of pigs weighing 25-62 kg can be secured safely and reliably with the sizes 3, 4 and 5 LMA-ProSeal. CLINICAL RELEVANCE: Endotracheal intubation in pigs can be difficult so there is a risk of hypoxemia in the apnoeic animal. With the LMA-ProSeal the airway can be secured rapidly, safely and reliably. Use of the Standard-LMA under PPV can be associated with gas leakage into the stomach and the subsequent risk of gastric distension and regurgitation. Both the ability to drain the stomach and the high P(leak) of the LMA-ProSeal could contribute to improved protection against aspiration under PPV.  相似文献   
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The molecular organization of presynaptic active zones during calcium influx-triggered neurotransmitter release is the focus of intense investigation. The Drosophila coiled-coil domain protein Bruchpilot (BRP) was observed in donut-shaped structures centered at active zones of neuromuscular synapses by using subdiffraction resolution STED (stimulated emission depletion) fluorescence microscopy. At brp mutant active zones, electron-dense projections (T-bars) were entirely lost, Ca2+ channels were reduced in density, evoked vesicle release was depressed, and short-term plasticity was altered. BRP-like proteins seem to establish proximity between Ca2+ channels and vesicles to allow efficient transmitter release and patterned synaptic plasticity.  相似文献   
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In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1-hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D-mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection.  相似文献   
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The microbiological meat examination (MFU), consisting of a bacteriological analysis and a testing for antibiotic residues, is one of several additional analyses used for an edibility rating of carcasses made during meat inspection. Reasons for performing a microbiological meat examination and procedures in the laboratory are defined in the Swiss ordinance for meat examination (FUV). The aim of this study was to analyze the data of 313 microbiological meat examinations from calves and 2882 microbiological meat examinations from cows carried out at the Institute for Food Safety and Hygiene during a period of 8 years. Reasons for microbiological meat examinations as reported by the meat inspectors were mainly classified to the category of "inflammation and necroses" (FUV, Annex 4, Pt 1.2; calves: 73%, cows: 48%). As declarations of the age of the pathological-anatomical changes (that influences directly the probability of detection of pathogens) were generally missing, it is not surprising that the compliance between a particular pathological-anatomical change and a specific detection of pathogens is poor (calves: 19%, cows: 18% of all MFU). About 18% (calves) and 45% (cows) of the reasons for microbiological meat examinations did not correspond to one of the reasons mentioned in the ordinance for meat examination. However, according to the data set, some reasons require a microbiological meat examination due to an often-found specific detection of pathogens. Otherwise, a remarkable number of reasons mentioned were missing the link to bacteriological etiology. Moreover, 14% (calf) and 7% (cow) of microbiological meat examinations with the declaration "no pretreatment" as well as 15% (calf) and 11% (cow) of microbiological meat examinations without declaration showed a positive result in the testing for antibiotic residues.  相似文献   
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