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排序方式: 共有118条查询结果,搜索用时 15 毫秒
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Matthias Dennler Inés Carrera Katrin Beckmann Julia Ritz Maja Rütten Patrick R. Kircher 《Veterinary radiology & ultrasound》2014,55(1):68-73
A 2‐month‐old female goat was presented for depressed mental status and multifocal central neurologic signs 3 weeks after hot‐iron disbudding. Conventional magnetic resonance imaging (MRI) findings included a large intra axial mass in the left frontal lobe that was T2 hyperintense and T1 hypointense centrally with a contrast‐enhancing peripheral capsule and perilesional T2 hyperintensity. A restrictive pattern was present in diffusion‐weighted imaging. Magnetic resonance spectroscopy demonstrated an increased amount of succinate, acetate, amino acids, lipids; minimal amounts of lactate; and decreased amounts of N‐acetyl aspartate and choline. A cerebral abscess due to Trueperella pyogenes was confirmed from necropsy and tissue culture. 相似文献
33.
Maša Bošnjak Mojca Kržan Urša Lampreht Tratar Jožica Dolenc Maja Čemažar Alenka Seliškar 《Veterinary anaesthesia and analgesia》2021,48(1):35-41
ObjectiveTo investigate the pharmacokinetics of carprofen after a single intravenous (IV) dose and multiple oral doses administered to pigs undergoing electroporation of the pancreas.Study designProspective experimental study.AnimalsA group of eight female pigs weighing 31.74 ± 2.24 kg (mean ± standard deviation).MethodsCarprofen 4 mg kg?1 was administered IV after placement of a central venous catheter during general anaesthesia with isoflurane. Blood samples were collected 30 seconds before and 5, 10, 20, 30 and 60 minutes and 2, 4, 6, 8, 12 and 24 hours after carprofen administration. Subsequently, the same dose of carprofen was administered orally, daily, for 6 consecutive days and blood collected at 36, 48, 60, 72, 96, 120, 144 and 168 hours after initial carprofen administration. Plasma was analysed using liquid chromatography with mass spectrometry. Standard pharmacokinetic parameters were calculated by compartmental analysis of plasma concentration–time curves. Data are presented as mean ± standard error.ResultsThe initial plasma concentration of IV carprofen was estimated at 54.57 ± 3.92 μg mL?1 and decreased to 8.26 ± 1.07 μg mL?1 24 hours later. The plasma elimination curve showed a bi-exponential decline: a rapid distribution phase with a distribution half-life of 0.21 ± 0.03 hours and a slower elimination phase with an elimination half-life of 17.31 ± 3.78 hours. The calculated pharmacokinetic parameters were as follows: the area under the plasma concentration–time curve was 357.3 ± 16.73 μg mL?1 hour, volume of distribution was 0.28 ± 0.07 L kg?1 and plasma clearance rate was 0.19 ± 0.009 mL minute?1 kg?1. The plasma concentration of carprofen, administered orally from days 2 to 7, varied from 9.03 ± 1.87 to 11.49 ± 2.15 μg mL?1.Conclusions and clinical relevanceCarprofen can be regarded as a long-acting non-steroidal anti-inflammatory drug in pigs. 相似文献
34.
Maja Cuvardic Steinar Tveitnes Tore Krogstad Peder Lombnæs 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):193-201
The effects of crop rotation and fertilization systems on yield and soil fertility parameters have been investigated in a long-term field trial established in southeast Norway in 1953. The results indicate the small differences between crop rotations and different fertilization systems in yield and soil fertility parameters; the decreasing trend in soil organic carbon (SOC) (from 3.8 to 3.7%) and increasing trend of N with time (from 0.32 to 0.36%) and, as a result, the decreasing trend in C/N ratio (from 12 to 10). 相似文献
35.
Ash dieback is an emerging disease caused by the fungus Chalara fraxinea that severely affects Fraxinus excelsior and F. angustifolia stands in Europe. Previous studies have shown that this pathogen prefers temperatures around 20°C, while its growth in pure cultures at 30°C proved to be very limited. The purpose of this study was to determine the effects of temperature on the development and growth of C. fraxinea in pure cultures and in plant tissues, as well as to test the heat tolerance of F. excelsior saplings. The sensitivity of fungus to heat in ash tissues was higher than in pure cultures. Low isolation success rate from diseased ash tissue after a five‐hour hot water treatment at 36°C and the relatively high survival rate of ash saplings after hot water treatments at 36°C and 40°C indicate possibilities for the development of a C. fraxinea eradication method in ash saplings. Field monitoring showed that in hot weather periods, thermal conditions inside the ash tissues can be extreme enough to markedly decrease the viability of C. fraxinea in infected plant tissues. 相似文献
36.
Jelena Nikolic Gordana Pantelic Dragana Todorovic Marija Jankovic Maja Eremi? Savkovic 《Water, air, and soil pollution》2012,223(8):4823-4829
After the accident in Fukushima reactors, a daily monitoring programme was initiated in two laboratories in Belgrade, one at the Vin??? Institute for Nuclear Sciences and the other at Institute for Occupational Health Karajovic. Samples of aerosol and fallout, as well as the random samples of food and water, were collected and analysed, using gross alpha/beta and gamma spectrometry, in order to establish the presence of traces of isotopes indicating Fukushima fallout. Gamma spectrometry measurement of these samples showed clear evidence of fission products 131I, 134Cs and 137Cs wtihin 2?weeks after the accident. The activity diminished with time due to dispersion in air and, in case of 131I, short half-life. 相似文献
37.
Darka Marković Stoja Milovanović Željko Radovanović Irena Zizovic Zoran Šaponjić Maja Radetić 《Fibers and Polymers》2018,19(6):1219-1227
This study discusses a novel approach for fabrication of floating photocatalyst which can be efficiently exploited for photodegradation of dyes in aqueous solutions. A fabrication of the floating photocatalyst consisted of two steps: transformation of the poly(ε-caprolactone) beads (PCLb) into poly(ε-caprolactone) foam (PCLf) with porous structure in supercritical carbon-dioxide and subsequent loading of PCLf with TiO2 nanoparticles (NPs). Morphological characterization of the PCLf before and after TiO2 NPs loading was carried out by FESEM. The presence of titanium on the surface and inside the PCLf was detected by EDX. Photocatalytical activity of the floating photocatalyst was investigated in aqueous solution of textile dyes C.I. Acid Orange 7 (AO7) and C.I. Basic Yellow 28 (BY28) which were exposed to lamp that simulates the sun light. In addition to sustainable floatability for a long period of time, developed floating photocatalyst exhibited high rate of photodegradation since the complete discoloration of AO7 and BY28 solutions and photocatalysts alone occurred after 300 and 180 min of illumination, respectively. Its photocatalytic activity was preserved after three repeated photodegradation cycles with unchanged chemical structure that was confirmed by FTIR analysis. 相似文献
38.
Branimir Urlić Maja Jukić Špika Christine Becker Hans-Peter Kläring Angelika Krumbein Smiljana Goreta Ban 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):748-757
The effect of suboptimal supply of nitrogen (N) and of replacing nitrate in the nutrient solution with ammonia on growth, yield, and nitrate concentration in green and red leaf lettuce was evaluated over two seasons (autumn and spring) using multiple regression analysis. The plants were grown in a greenhouse on a Nutrient Film Technique (NFT) system. Nitrogen concentrations in the nutrient solution were either 3?mM or 12?mM, and the form of N was varied as follows: 100% NO3, 50% NO3?+?50% NH4, and 100% NH4. In both seasons, the biomass (fresh weight) of lettuce heads increased with increasing NO3 concentrations and in autumn, NO3 even at 1.5?mM was sufficient for high yield. However, head dry weight was affected neither by the season nor by changes in the composition of the nutrient solution. The concentration of NO3 had no effect on root dry weight, but it decreased at higher concentrations of NH4. The number of leaves increased as the ratio of NO3 to NH4 in the nutrient solution increased and was higher in autumn because of the longer growth period. Increasing the concentration of NO3 in nutrient solution increased both total N and nitrate concentration in lettuce heads (dry weight) but decreased the concentration of total C. Also, leaf nitrate concentration was lower in spring than in autumn and decreased with increasing NH4 concentration. Nitrogen utilization efficiency was maximum when NH4 levels in the nutrient solution were either 0% or 50% irrespective of the season. Our results thus show that suboptimal N supply in autumn will not affect lettuce yield, and that nitrate concentration in leaves is lower when NH4 concentrations in nutrient solution are higher and also much lower in red lettuce than in green lettuce. 相似文献
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Serge Utevsky Maja Zagmajster Andrei Atemasov Oleksandr Zinenko Olga Utevska Andrei Utevsky Peter Trontelj 《水产资源保护:海洋与淡水生态系统》2010,20(2):198-210
1. Distribution and status of medicinal leeches were re‐considered in the light of the new taxonomy recognizing four Western Palaearctic species: Hirudo medicinalis, Hirudo verbana, Hirudo orientalis and Hirudo troctina. 2. Recent records and new data obtained on expeditions to Ukraine, Russia, Azerbaijan, Kazakhstan, Uzbekistan and the Western Balkans were mapped to obtain an up‐to‐date overview of the distribution. 3. Three hypotheses explaining the current ranges of all Hirudo species were tested. The ecological hypothesis, suggesting a strong impact of large‐scale environmental factors, received the highest support, while anthropogenic influence was minimal, and no historical patterns of refugia and colonization were detected. 4. Mapped localities of all Hirudo species show extensive, belt‐shaped ranges extending from east to west. H. medicinalis is distributed from Britain and southern Norway to the southern Urals and probably as far as the Altai Mountains, occupying the deciduous arboreal zone. H. verbana has been recorded from Switzerland and Italy to Turkey and Uzbekistan, which largely corresponds to the Mediterranean and sub‐boreal steppe zone. H. orientalis is associated with mountainous areas in the sub‐boreal eremial zone and occurs in Transcaucasian countries, Iran and Central Asia. H. troctina has been found in north‐western Africa and Spain in the Mediterranean zone. 5. Based on the data gathered, and considering real and potential threats, global IUCN category Near Threatened is proposed for H. medicinalis, H. verbana, and H. orientalis, while H. troctina can only be assigned to category Data Deficient. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献