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排序方式: 共有170条查询结果,搜索用时 78 毫秒
81.
82.
Sergio Miguel Vélez-Zambrano Jefferson Bertin Vélez-Olmedo Susana García Bianca S. A. Bonfim Pedro Emilio Cedeño Danilo Pinho 《Forest Pathology》2023,53(5):e12830
Teak is a very important tropical timber in Ecuador. In 2017, teak samples displaying stem canker symptoms were collected in two provinces of Ecuador. From 11 symptomatic trees, 11 isolates resembling a species of Lasiodiplodia were obtained. All isolates obtained induced stem canker on teak plants after artificial inoculation, confirming them as the cause of the observed canker symptoms. Bayesian inference with concatenated sequences of complete ITS and partial TEF-α and β-TUB gene sequences from two representative isolates clustered teak isolates with other sequences of Lasiodiplodia theobromae available in Genbank. This is the first report of L. theobromae causing stem canker on teak plants in Ecuador. 相似文献
83.
Luis Augusto Di Loreto Di Raimo Eduardo Guimarães Couto José Alexandre Mello Demattê Ricardo Santos Silva Amorim Gilmar Nunes Torres Cassiano Cremon Danilo César de Mello Edwaldo Dias Bocuti Raul Roberto Poppiel Adeilson Nascimento da Silva Lucas Nunes Lima Luis Carlos Gomes Neto 《European Journal of Soil Science》2022,73(2):e13227
84.
Locatelli C Santini A Bonometti GA Palermo V Scarpa P Sala E Brambilla PG 《The Journal of small animal practice》2011,52(5):246-253
Objectives : To assess the influence of body surface area, age and gender on echocardiographic parameters and to establish echocardiographic reference values for dogue de Bordeaux dogs. Methods : Thirty‐nine healthy dogue de Bordeaux dogs of both sexes, older than one year, were recruited and 31 of these were included in the study. The classic linear regression model proved to be the best way to analyse the data. The reference limits of the echocardiographic measurements were calculated using the regression equations. The difference between the mean values of body surface area in both gender groups was evaluated by using one‐way ANOVA. Results : A significant correlation was seen between several echocardiographic parameters and body surface area or body surface area and age, and high coefficients of determination (R2) were found. No effect of gender was detected on echocardiographic variables, except for the thickness of the left ventricular posterior wall at end diastole. Clinical Significance : The echocardiographic parameters related to body surface area, in the absence of correlation with other independent variables (gender and age) should be interpreted with caution because their variation could be significant for the presence of heart disease. The proposed statistical model allows estimation of echocardiographic parameters in dogue de Bordeaux dogs with different body surface areas and ages. 相似文献
85.
Malasarn D Saltikov CW Campbell KM Santini JM Hering JG Newman DK 《Science (New York, N.Y.)》2004,306(5695):455
Arsenate [As(V)]-respiring bacteria affect the speciation and mobilization of arsenic in the environment. This can lead to arsenic contamination of drinking water supplies and deleterious consequences for human health. Using molecular genetics, we show that the functional gene for As(V) respiration, arrA, is highly conserved; that it is required for As(V) reduction to arsenite when arsenic is sorbed onto iron minerals; and that it can be used to identify the presence and activity of As(V)-respiring bacteria in arsenic-contaminated iron-rich sediments. The expression of arrA thus can be used to monitor sites in which As(V)-respiring bacteria may be controlling arsenic geochemistry. 相似文献
86.
Ireneo J. Manguiat Danilo M. Mendoza Arnel M. Perez Tadakatsu Yoneyama 《Soil Science and Plant Nutrition》2013,59(4):593-604
Abstract A study was carried out to compare the difference or N-yield method with the 15N natural abundance method for the estimation of the fractional contribution of biological N2 fixation in the different plant parts of nodulating and non-nodulating isolines of soybeans. The results indicated that the δ15N values of most plant parts of soybeans were significantly lower (p<0.05) in the nodulating than in the non-nodulating isoline. However, in the case of the root+nodule component, the δ15N value was higher in the nodulating than in the non-nodulating isoline possibly due to isotopic discrimination of 15N over 14N which may have occurred in the nodules. Inoculation of soybeans with the Bradyrhizobium japonicum strain CB 1809 increased significantly (p<0.05) the δ15N value of the root+nodule component implying that the effectiveness of the soybean-rhizobium symbiosis had increased by inoculation. Percentage of plant N derived from atmospheric N2 fixation (%Ndfa) estimated by the 15N natural abundance method was highly correlated (r=0.762, p<0.01) with that by the difference or N-yield method and the differences between the two methods were not statistically significant. The agreement between the two methods was closer at maturity than at the early reproductive stage. The %Ndfa obtained by the difference method ranged from 48.4 to 92.6% whereas the %Ndfa obtained by the 15N natural abundance method ranged from 43.2 to 92.4% in the different plant parts. Based on the 15N natural abundance method, approximately 15% of the N in pod, shoot, grain, and shell was derived from the soil but in the case of stover, this fraction was about 55%. 相似文献
87.
Antonello Santini Antonia Šrobárová Ján Pavlovkin Milada Čiamporová Alberto Ritieni 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(4):363-371
The possible role of the fusariotoxin, fusaproliferin in plant pathology was investigated with respect to cell membrane potential.
Electron microscopy was used to study both the early effect of fusaproliferin on the host’s plasma membrane and ultrastructure
responses in the cells of maize leaves. The seedlings of resistant (Lucia) and susceptible (Pavla) to the fusaproliferin maize
cultivars were grown in the presence of fusaproliferin at different concentrations, namely 5 and 35 μg ml−1, respectively, and electrophysiological measurements were compared with those obtained using two different toxic compounds,
namely fusicoccin and 3-3(3,4 dichlorophenyl)-1,1-dimethylurea (DCMU). It was observed that only the higher concentration of fusaproliferin induced the onset of visible symptoms on the
leaves. Comparing the effect of fusaproliferin to that of fusicoccin and DCMU at the higher toxin concentration, it was observed
that functional differences in membrane potential induced severe damage to the mesophyll and outer chloroplast membrane; the
extent of changes in electrophysiology and ultrastructure disturbances depended on the toxin concentration and was greater
in the susceptible cv. Pavla. Results indicated that fusaproliferin could be involved in Fusarium pathogenesis either as a virulence factor or by enhancing the activity of other toxins that might be concomitantly present
in infected plants. 相似文献
88.
89.
Leptoglossus occidentalis, an insect native to North America, was inadvertently introduced into Italy about 1999. The insect damages the cones of conifer trees, especially Pinus pinea (Italian Stone pine). Pinus pinea is also affected by Diplodia pinea, a fungus native to Italy, which is becoming an increasing threat because pine trees are becoming more susceptible to it as a consequence of global warming. Because the insect and the fungus both have the pine cones as a common habitat, a possible interaction between them has been postulated. The aim of this study was to ascertain whether L. occidentalis and D. pinea interact on P. pinea cones. The interaction was studied using real‐time PCR on a group of naturally infected insects collected from a forest, and a group raised in the laboratory and artificially inoculated with D. pinea conidia. Molecular analysis showed that D. pinea DNA occurred on both naturally infected and inoculated insects, but with significant differences between the two groups. The rapid and sensitive molecular technique made it possible to detect D. pinea DNA on the bodies of the insects, and to show that the native D. pinea occurred on the exotic insect. 相似文献
90.
Darley Oliveira Cutrim Kaliandra Souza Alves Luis Rennan Sampaio Oliveira Rozilda da Concei??o dos Santos Vanessa Jaqueline Veloso da Mata Danilo Moreira do Carmo Daiany íris Gomes Rafael Mezzomo Francisco Fernando Ramos de Carvalho 《Tropical animal health and production》2012,44(8):1855-1863
We aimed to evaluate the effects of diets, based on elephant grass or sugarcane as roughage and corn meal or rice bran as energy concentrate, on performance and body composition in terms of diet intake and digestibility. A total of 30 Santa Ines crossbreds (SIC), castrated male sheep with 19.8?±?2.0?kg initial body weight (BW) were used. Six animals were slaughtered at the onset of the experiment to estimate the initial body composition for the other animals. The remaining 24 animals were distributed in a completely randomized 2?×?2 factorial design, with four treatments (two roughages and two concentrates) and six replicates. The sheep were slaughtered when they reached 30.0?kg BW. Elephant grass diets provided higher intake and digestibility than sugarcane diets for the following contents: dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre, minerals, total carbohydrates (TC), and total digestible nutrients (TDN). Among the concentrates, corn meal diets were associated with higher intakes than rice bran diets for the following contents: DM, OM, CP, TC, and TDN. Animals from all of the treatments exhibited low average daily weight gain and low protein and high fat and energy body levels. Sugarcane and rice bran can be used as ingredients in diets for sheep with low weight gain potential. Regardless of roughage or concentrate types used in diets for confined SIC sheep, performance and body composition remained unaltered. 相似文献