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211.
Pest resistance in Solanum galapagense has been associated with the presence of type IV glandular trichomes and allelochemicals. Knowledge of the genetic factors involved in determining the presence and type of trichomes may assist in the process of gene introgression for development of pest resistant tomato cultivars. In this study, we sought to identify QTLs associated with the presence of type IV trichomes in an F2 population derived from the interspecific cross of Solanum lycopersicum TOM-684?×?S. galapagense accession LA1401. Two QTLs contributing to type IV trichome occurrence and density were detected, one major QTL (gal.IV-2), responsible for 35.22% of phenotypic variation, was located on chromosome 2. The other QTL (gal.IV-3) was located on chromosome 3, and explained 23.35% of the phenotypic variation in the F2 population. These QTLs were responsible for 26.44 and 3.37% of the variation observed in a progeny derived from a backcross to TOM-684. The same QTLs were also associated with type II?+?III non-glandular trichomes, whose densities were negatively correlated to those of type IV trichomes, suggesting that the loci found may have pleiotropic effects for high type IV/low type II?+?III trichome densities. Our results indicate that the inheritance for type IV trichomes can be explained by a few genetic factors affecting the presence of a gland and the density of trichomes. These results further suggest a revision to trichome classification used for tomato may be appropriate.  相似文献   
212.
Tropical Animal Health and Production - The aim of this trial was to determine the effect of ruminal fluid adapted to crude glycerol supplementation on in vitro methane and fermentation parameters...  相似文献   
213.
ObjectivesTo compare pulmonary gas exchange, tissue oxygenation and cardiovascular effects of four levels of end-expiratory pressure: no positive end-expiratory pressure (ZEEP), positive end-expiratory pressure (PEEP) of maximal respiratory system compliance (PEEPmaxCrs), PEEPmaxCrs + 2 cmH2O (PEEPmaxCrs+2), PEEPmaxCrs + 4 cmH2O (PEEPmaxCrs+4), in isoflurane-anesthetized dogs.Study designProspective randomized crossover study.AnimalsA total of seven healthy male Beagle dogs, aged 1 year and weighing 10.2 ± 0.7 kg (mean ± standard deviation).MethodsThe dogs were administered acepromazine and anesthesia was induced with propofol and maintained with isoflurane. Ventilation was controlled for 4 hours with ZEEP, PEEPmaxCrs, PEEPmaxCrs+2 or PEEPmaxCrs+4. Cardiovascular, pulmonary gas exchange and tissue oxygenation data were evaluated at 5, 60, 120, 180 and 240 minutes of ventilation and compared using a mixed-model anova followed by Bonferroni test. p < 0.05 was considered significant.ResultsCardiac index (CI) and mean arterial pressure (MAP) were lower in all PEEP treatments at 5 minutes when compared with ZEEP. CI persisted lower throughout the 4 hours only in PEEPmaxCrs+4 with the lowest CI at 5 minutes (2.15 ± 0.70 versus 3.45 ± 0.94 L minute–1 m–2). At 180 and 240 minutes, MAP was lower in PEEPmaxCrs+4 than in PEEPmaxCrs, with the lowest value at 180 minutes (58 ± 7 versus 67 ± 7 mmHg). Oxygen delivery index (DO2I) was lower in PEEPmaxCrs+4 than in ZEEP at 5, 60, 120 and 180 minutes. Venous admixture was not different among treatments.Conclusion and clinical relevanceThe use of PEEP caused a transient decrease in MAP and CI in lung-healthy dogs anesthetized with isoflurane, which improved after 60 minutes of ventilation in all levels of PEEP except PEEPmaxCrs+4. A clinically significant improvement in arterial oxygenation and DO2I was not observed with PEEPmaxCrs and PEEPmaxCrs+2 in comparison with ZEEP, whereas PEEPmaxCrs+4 decreased DO2I.  相似文献   
214.
ObjectiveTo describe the pharmacokinetics of buprenorphine in dogs following administration of a high-concentration formulation of buprenorphine.Study designProspective, randomized, crossover study.AnimalsA total of six healthy male intact Beagle dogs, aged 9–13 months and weighing 10.3 ± 1.4 kg (mean ± standard deviation).MethodsDogs were randomized to be administered buprenorphine (0.12 mg kg–1; Simbadol, 1.8 mg mL–1) via the intravenous (lateral saphenous) or subcutaneous (dorsal interscapular) route followed by the alternative route of administration after a 14 day interval. Blood was sampled before administration and at set times up to 72 hours after injection. Plasma buprenorphine concentration was measured using liquid chromatography–tandem mass spectrometry.ResultsA three-compartment model with zero or biphasic rapid and slow first-order input in (intravenous or subcutaneous data, respectively) and first-order elimination from the central compartment best fitted the data. The rapid first-order input accounted for 63% of the dosage absorption. Typical values (% interindividual variability) for the three compartment volumes were 900 (33), 2425 (not estimated) and 6360 (28) mL kg–1. The metabolic and two distribution clearances were 25.7 (21), 107.5 (74) and 5.7 (61) mL minute–1 kg–1. The absorption half-life for the fast absorption phase was 8.9 minutes with a 0.7 (103) minute delay. The absorption half-life for the slow absorption phase was 347 minutes with a 226 (42) minute delay. Median (range) bioavailability calculated from noncompartmental analysis was 143 (80–239)%. Calculated terminal half-life was 963 minutes.Conclusions and clinical relevanceThe high-concentration formulation of buprenorphine administered subcutaneously had a large volume of distribution and a rapid absorption phase followed by slower, delayed absorption. The high estimate of bioavailability should be interpreted with caution as values above 100% are most commonly related to experimental issues.  相似文献   
215.
A pilot program to evaluate the feasibility of collecting juvenile (seed) scallops using Japanese technology was carried out from October 2001 to April 2002 in the Marine Reserve at La Rinconada, Antofagasta, Chile. The continuous presence of larvae in waters in the reserve allowed for collection of 400–15,340 spat per collector and showed the high reproductive capability of local scallops and the relationship between numbers of larvae in the water and amount of spatfall. Highest rates of settlement were proportional to high numbers of umbone larvae in the water at >5000 larvae m−3 when collectors were first immersed. Absence of a relationship between larval numbers and postlarval settlement with trophic factors such as chlorophyll and particulate organic matter in the water suggests that productivity was not limited by these factors. Harvest of spat from collectors immersed for four and five months had recovery efficiencies of 5.5% and 59.4% compared with settlement in collectors after immersion for one month. Cohort analyses of recovered spat suggested that settlement occurred over the lengthy immersion period and was due to the continuous presence of larvae in the water. The loss of a high percentage of spat over the 4–5 immersion period compared with settlement in the first month can be attributed to intraspecific competition of spat density and growth as well as clogging of the collectors by sediment and marine fouling that impeded a flow of water through the nets.  相似文献   
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218.
Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, is one of the most devastating diseases affecting maize yield worldwide. A foliar spray of nickel (Ni) to potentiate maize resistance against NCLB was investigated by examining alterations in the photosynthetic apparatus (leaf gas exchange and chlorophyll [Chl] a fluorescence parameters), production of ethylene and reactive oxygen species as well as activities of defence and antioxidant enzymes. Mycelial growth of E. turcicum was inhibited by Ni in vitro. Inoculated plants sprayed with Ni exhibited higher foliar Ni concentration, reduced NCLB symptoms, and lower concentrations of malondialdehyde and hydrogen peroxide. In inoculated leaves of plants not sprayed with Ni, concentrations of Chl a, Chl b, and carotenoids were lower and the photosynthetic apparatus was impaired at the biochemical level due to high NCLB severity. The activities of antioxidant enzymes were not affected by Ni, except an increase in glutathione reductase activity for noninoculated plants sprayed with Ni. High lipoxygenase and polyphenoloxidase activities, lower ethylene production, as well as elevated production of phenolics and lignin helped decrease NCLB severity in the leaves of Ni-sprayed plants.  相似文献   
219.
Résumé On présente les résultats des recherches effectuées pendant 4 ans, sur la persistence du parathion et du méthylparathion dans les tubercules de pomme de terre et dans le sol, à la suite des traitements du sol avec des préparations en poudre. On a effectué des déterminations pour la récolte de la même année et pour celle de l'année suivante, c'est-à-dire 6 mois et respectivement 18 mois après le traitement.En général, les résidus accumulés dans les pommes de terre ont varié entre 0,08 et 0,44 ppm. Le dépôt résiduel accumulé pendant 6 mois dans les pommes de terre présente des valeurs voisines de celles accumulé et après un intervalle de 18 mois.La quantité de substance toxique présente dans le sol au moment de la récolte a été de 3 à 6 fois plus grande que celle trouvée dans les tubercules récoltés du même sol, et elle a varié entre 0,27 et 0,58 ppm.
Summary During 4 years, investigations have been carried out on parathion and methylparathion residues in potato tubers and in soil, following soil treatments with dust preparations. Determinations were made for the crop of the same year, as well as for that of the next year, i.e. 6 months and 18 months after the treatment, respectively. In all cases, except in one year, the residues which accumulated in potatoes 6 months later, had values close to those of the residual deposit accumulated after 18 months.At harvesting, the amount of toxicant available in the soil was 3 to 6 times larger than that found in potato tubers harvested on the same soil, and varied between 0.27–0.58 ppm.No evident differences between the amounts of parathion and methylparathion residues were found, and this suggests that the same degradation factor acts on both compounds.The precipitations played an important role; thus in years with low precipitations, the toxicant deposits increased in the soil and, implicitly, also in the tubers.

Zusammenfassung Es werden die Ergebnisse einer vierjährigen Forschungsarbeit über die Verweildauer von Parathion und Methylparathion in der Kartoffelknolle und im Boden nach Bodenbehandlungen mit Stäubemitteln zusammengefaßt. Die Rückstandsanalysen wurden am Erntegut desselben Jahres, das heißt 6 Monate nach der Behandlung, und am Erntegut des nächsten Jahres, also 18 Monate nach dem Zeitpunkt der Behandlung, durchgeführt.Mit Ausnahme eines einzigen Jahres erreichte der Rückstand in der Kartoffelknolle in allen Fällen Werte zwischen 0,08 und 0,44 ppm. Die nach 6 Monaten in den Knollen festgestellten Rückstandswerte unterscheiden sich von den nach 18 Monaten nachgewiesenen nur unwesentlich.Im Boden wurden zur Zeit der Ernte drei- bis sechsmal höhere Rückstandswerte gefunden als in Knollen. Dieselben variierten zwischen 0,27 und 0,58 ppm.Die Rückstandswerte für Parathion und für Methylparathion zeigten keine deutlichen Unterschiede. Dies läßt auf die Einwirkung der gleichen Abbaufaktoren für beide Verbindungen schließen. Eine besondere Bedeutung unter den Klimafaktoren kam den Niederschlägen zu. In Jahren, in denen diese gering waren, wurden größere Rückstandswerte im Boden und auch in den Kartoffelknollen festgestellt.
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220.
A structure-antifungal activity relationship (SAR) study of 22 related cinnamic acid derivatives was carried out. Attention was focused on the antifungal activities exhibited against Aspergillus flavus, Aspergillus terreus, and Aspergillus niger. (E)-3-(4-methoxy-3-(3-methylbut-2-enyl)phenyl)acrylic acid (16) exhibited antifungal activity against A. niger, comparable to that of miconazole and a significant antifungal effect against A. flavus and A. terreus as well. A structure-activity relationship (SAR) study of related cinnamic acid derivatives has allowed a model to be proposed for the recognition of the minimal structural requirements for the antifungal effect in this series.  相似文献   
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