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151.
The chemical and microbial properties of afforested mine soils are likely to depend on the species composition of the introduced
vegetation. This study compared the chemical and microbial properties of organic horizons and the uppermost mineral layers
in mine soils under pure pine (Pinus sylvestris), birch (Betula pendula), larch (Larix decidua), alder (Alnus glutinosa), and mixed pine–alder and birch–alder forest stands. The studied properties included soil pH, content of organic C (Corg) and total N (Nt), microbial biomass (Cmic), basal respiration, nitrogen mineralization rate (Min-N), and the activities of dehydrogenase, acid phosphomonoesterase,
and urease. Near-infrared spectroscopy (NIR) was used to detect differences in the chemical composition of soil organic matter
under the studied forest stands. There were significant differences in Corg and Nt contents between stands in both O and mineral soil horizons and also in the chemical composition of the accumulated organic
matter, as indicated by NIR spectra differences. Alder was associated with the largest Corg and Nt accumulation but also with a significant decrease of pH in the mineral soil. Microbial biomass, respiration, the percentage
of Corg present as Cmic, Min-N, and dehydrogenase activity were the highest under the birch stand, indicating a positive effect of birch on soil
microflora. Admixture of alder to coniferous stand increased basal respiration, Min-N, and activities of dehydrogenase and
acid phosphomonoesterase as compared with the pure pine stand. In the O horizon, soil pH and Nt content had the most important effects on all microbial properties. In this horizon, the activities of urease and acid phosphomonoesterase
did not depend on microbial biomass. In the mineral layer, however, the amount of accumulated C and microbial biomass were
of primary importance for the enzyme activities. 相似文献
152.
153.
Mukund D. Patil Bhabani S. Das Eran Barak Pratap B. S. Bhadoria Amir Polak 《Paddy and Water Environment》2010,8(2):189-198
Polymer-coated urea (PCU) is an important alternative to uncoated urea for improving nitrogen (N) use efficiency (NUE). Only
a few studies discuss their utility for lowland rice systems. A 2-year field study was conducted to examine if nitrogen loading
is reduced in lowland rice ecosystem by using mixture of PCU and uncoated urea without sacrificing yield. Five treatments
involving two mixtures of PCU with 50 and 70% coated urea each at 70 and 50% of recommended dose (80 kg N ha−1) and one with uncoated urea at 100% recommended dose were laid out in a completely randomized design. Selected plant growth
parameters and plant available N contents (NH4–N plus NO3–N) in soil solution and ponded water were measured over a period of 65 days after transplanting. Results showed no significant
difference for vegetative and yield parameters among different treatments suggesting that treatments receiving lower doses
of nitrogen exhibited higher NUE. Analysis of partial factor of productivity (PFP) for N suggested that the total N dose may
be reduced by 50% using mixtures of coated and uncoated urea. Similarly, statistically similar PFP values for treatments receiving
the same amount of total N for both years and for both total N dose suggested that the proportion of coated urea may also
be reduced to as low as 50% without sacrificing yield. Correlation analysis on nitrogen contents in ponded water and soil
solutions and the analysis of water productivity and PFP showed that soil water regime could also significantly influence
the nitrogen status in soil even when PCU are applied. In turn, both the water regime and N contents in soil ultimately influences
grain yield. Although the constant release of N from coated fertilizer ensures adequate N supply for plant uptake, it may
not completely avoid N deficit condition especially during heavy rainfall. Analysis of the developed production function suggested
that 55–65% polymer coating and about 100 cm total water input may be ideal for achieving maximum yield. The production function
was developed for PCU treatments using data observed in treatments receiving 70% recommended N dose. The range of water input
in these treatments was 86.5–174.0 cm. 相似文献
154.
Sliwa E Adaszek Ł Tatara M Dobrowolski P 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(9-10):397-405
The aim of this study was to investigate short-term 4 and 14 weeks after fundectomy) and long-term (at the age of 8 months) postoperative effects of 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate on selected serum biochemical markers in fundectomized pigs. Experimental fundectomy was performed in 30 castrated male pigs of the Pu?awska breed who received placebo or 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate up to the age of 8 months. Plasma amino acid concentrations and selected blood parameters were analyzed. Main vital organs were weighed. Our study showed that the supplementations with alpha-ketoglutarate and/or 3-hydroxy-3-methylbutyrate to fundectomized pigs significantly prevented the reduction of stomach, liver and spleen weights. However, results of this study, either positive or negative, cannot categorically establish a beneficial effect of AKG and HMB nutritional support after fundectomy in pigs. 相似文献
155.
156.
157.
Polak M Gajecka M Jakimiuk E Obremski K Gajecki M Smoczyński L Luczyński M Góra M Baranowski M Zielonka L Zwierzchowski W 《Polish journal of veterinary sciences》2004,7(3):187-191
Zearalenone (ZEA) is a member of macrocyclic lactons family. It is a toxin--phytosteride produced by fungi of Fusarium ssp. genus. Zearalenone contaminates food and animal feeding stuffs and its destruction is difficult. It requires application of particular compounds that would bind zearalenone in the feed or feeding stuff or in the gastrointestinal tract and decrease its bio-accessibility. It should also fulfil all the safety requirements regarding the plant supplements and animals that are fed with this feed. The aim of the study was to estimate if the feed supplemented with different doses of zearalenone and zearalenone destructor causes changes of the metabolic profile in gilts. The results obtained show that applied destructor did not cause negative haematological and biochemical changes in the blood of the gilts examined. It can be suggested that it is a safe feed supplement pigs in prevention of zearalenone micotoxicosis. 相似文献
158.
Gajecka M Jakimiuk E Skorska-Wyszyńska E Zielonka L Polak M Paluszewski A Rybarczyk L Gajecki M 《Polish journal of veterinary sciences》2004,7(3):175-180
The immunological, haematological and biochemical analyses of blood plasma in bitches with 50 days lasting induced zearalenone micotoxicosis were carried out. It can be indirectly suggested that the inhibition of the humoral reaction of the organism, stimulation of detoxification effect in the liver and decreased cellular answer took place. 相似文献
159.
Michał Czopowicz Olga Szaluś‐Jordanow Marcin Mickiewicz Agata Moroz Lucjan Witkowski Iwona Markowska‐Daniel Daria Reczyńska Emilia Bagnicka Jarosław Kaba 《Animal Science Journal》2018,89(9):1364-1370
We carried out this study to determine for how long small ruminant lentivirus (SRLV)‐specific antibodies can be detected by three commercial ELISA kits in goat kids after suckling infected does in field conditions. Forty‐one kids born to SRLV‐seropositive asymptomatic does were blood sampled prior to colostrum consumption, and then weekly for 6 months in total. The sera were screened with three commercial ELISA kits: whole‐virus ELISA (wELISA), recombinant transmembrane and capsid antigen ELISA (TM/CA‐ELISA), and surface antigen ELISA (SU‐ELISA). All but one kid were seronegative in all three ELISAs right after birth. At the age of 1 week all kids turned seropositive in wELISA, 39 kids (95%) in TM/CA‐ELISA, and 35 kids (85%) in SU‐ELISA. All seropositive kids turned seronegative in wELISA by the 15th week, and in SU‐ELISA by the 19th week (median of 8 weeks in both ELISA), whereas in TM/CA‐ELISA five kids (13% of 39 initially seropositive) were still seropositive at the age of 6 months (median of 11 weeks). Antibody levels at the age of 1 week proved significantly linked to the duration of maternal antibodies in all three ELISAs and could be employed to predict for how long maternal antibodies would remain detectable. 相似文献
160.