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561.
To investigate the interactive effects of temperature and photoperiod on the growth performance, feeding parameters and muscle growth dynamics in juvenile Atlantic halibut (Hippoglossus hippoglossus L.), a total of 1212 juvenile halibut, including 383 tagged fish (mean initial weight of tagged individuals: 17.6 ± 0.3 g SE), were reared under a simulated natural light regime for Bergen (60°25′N) or continuous light at 9, 12 and 15 °C from 3 December 2007 until 11 March 2008. The mean weight and growth rate were significantly higher at 12 and 15 °C than at 9 °C. In addition, significantly higher mean weight and growth rate were observed in halibut reared under continuous light at a low temperature, indicating an interactive effect of temperature and photoperiod on growth performance. No effect of temperature or photoperiod was found with respect to feed conversion efficiency, whereas a higher feed consumption at increasing temperature and a higher overall daily feeding rate at continuous light at a low temperature were observed. Indications of continuous light having a stronger effect at low temperatures on muscle growth dynamics were found. A difference in the size class distribution of fibre diameter was found between photoperiod treatments at 9 °C, suggesting that continuous light resulted in elevated hypertrophic growth at low temperature. This may suggest that the increased growth rate found at continuous light at 9 °C may be a result of hypertrophic growth in juvenile halibut. 相似文献
562.
Karin Thygesen Lise Nistrup Jørgensen Kim Skov Jensen Lisa Munk 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(4):435-447
Field experiments, involving various fungicide strategies with pyraclostrobin and/or epoxiconazole were carried out in 2004
and 2005, with the overall purpose of monitoring the evolution of fungicide sensitivity in Mycosphaerella graminicola on different isolates per leaf, leaf levels at different points of time, and points in the field. Sensitivity was assessed
on single isolates by means of epoxiconazole EC50-values, and monitoring of the G143A-mutation, which confers strobilurin resistance. In both years, fungicide application
strategies did not cause any significant shifts in epoxiconazole sensitivity of the population median or variance over time
compared to the starting population. In 2004, the end-population median was the same for all sprayed strategies, although
compared to untreated median sensitivities were higher. In 2005, epoxiconazole sensitivity levels were similar on individual
flag leaves and different points in the field. Measured on all isolates the EC50-values ranged from 0.007–1.15 mg l−1. In 2004, due to the high initial level of pyraclostrobin resistance, stabilisation of pyraclostrobin resistance was observed
following the various combination treatments. No correlation between epoxiconazole sensitivities and pyraclostrobin resistance
were observed. High input strategies using a mixture of epoxiconazole and pyraclostrobin resulted in the best control and
yield response. A subpopulation of the isolates from 2004 was also screened for sensitivity towards five different triazoles
of which tebuconazole proved to be least sensitive, and this could further be split into two subpopulations. 相似文献
563.
564.
Marika Lyly Marjatta Salmenkallio‐Marttila Tapani Suortti Karin Autio Kaisa Poutanen Liisa Lhteenmki 《Cereal Chemistry》2003,80(5):536-541
The aim was to study the effect of concentration and molecular weight of four different β‐glucan preparations on the perceived sensory quality of a beverage prototype. The correlations between sensory and instrumental measures were investigated. Two of the preparations were brantype containing high molecular weight β‐glucan, two were more‐processed low molecular weight β‐glucan preparations. Twelve beverage samples containing 0.25–2% β‐glucan and one reference sample thickened with carboxymethyl cellulose (CMC) were profiled by a sensory panel and analyzed by instrumental measurements (viscosity and molecular weight). Sensory profiles of the beverages varied at the same concentration of β‐glucan, depending on β‐glucan preparation. Beverages made with the bran‐type preparations were more viscous and had higher perceived thickness than beverages made with more‐processed, low molecular weight preparations. Moderate correlations were obtained between perceived thickness and sliminess and instrumental viscosity at all shear rates between 26 and 100/sec (r = 0.63–0.78; P ≤ 0.001). Technologically, more‐processed β‐glucan preparations are easier to add into a beverage in amounts sufficient for achieving a physiologically functional amount of β‐glucan in a product. 相似文献