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91.
COMPARISON BETWEEN PROTON MAGNETIC RESONANCE SPECTROSCOPY FINDINGS IN DOGS WITH TICK‐BORNE ENCEPHALITIS AND CLINICALLY NORMAL DOGS 下载免费PDF全文
Christine Sievert Henning Richter Katrin Beckmann Patrick R. Kircher Ines Carrera 《Veterinary radiology & ultrasound》2017,58(1):53-61
In vivo diagnosis of tick‐borne encephalitis is difficult due to high seroprevalence and rapid viral clearance, limiting detection of antibodies in blood and cerebrospinal fluid. Magnetic resonance imaging (MRI) characteristics of tick‐borne encephalitis have been reported, however MRI studies can also be negative despite the presence of neurologic signs. Magnetic resonance spectroscopy (1H MRS) is an imaging method that provides additional information about the metabolic characteristics of brain tissues. The purpose of this retrospective cross‐sectional study was to describe brain metabolites using short echo time single‐voxel 1H MRS in dogs with confirmed tick‐borne encephalitis and compare them with healthy dogs. Inclusion criteria for the affected dogs were neurological symptoms suggestive of tick‐borne encephalitis, previous endemic stay and tick‐bite, diagnostic quality brain MRI and 1H MRS studies, and positive antibody titers or confirmation of tick‐borne encephalitis with necropsy. Control dogs were 10, clinically normal beagles that had been used in a previous study. A total of six affected dogs met inclusion criteria. All dogs affected with tick‐borne encephalitis had 1H MRS metabolite concentration alterations versus control dogs. These changes included mild to moderate decreases in N‐acetyl aspartate and creatine peaks, and mild increases in glutamate/glutamine peaks. No lactate or lipid signal was detected in any dog. Myoinositol and choline signals did not differ between affected and control dogs. In conclusion, findings supported the use of 1H MRS as an adjunctive imaging method for dogs with suspected tick‐borne encephalitis and inconclusive conventional MRI findings. 相似文献
92.
93.
Pagani L Steinacker J Bacmann A Stutz A Henning T 《Science (New York, N.Y.)》2010,329(5999):1622-1624
Cold molecular clouds are the birthplaces of stars and planets, where dense cores of gas collapse to form protostars. The dust mixed in these clouds is thought to be made of grains of an average size of 0.1 micrometer. We report the widespread detection of the coreshine effect as a direct sign of the existence of grown, micrometer-sized dust grains. This effect is seen in half of the cores we have analyzed in our survey, spanning all Galactic longitudes, and is dominated by changes in the internal properties and local environment of the cores, implying that the coreshine effect can be used to constrain fundamental core properties such as the three-dimensional density structure and ages and also the grain characteristics themselves. 相似文献
94.
95.
Rainer Froese Nazli Demirel Gianpaolo Coro Kristin M Kleisner Henning Winker 《Fish and Fisheries》2017,18(3):506-526
This study presents a Monte Carlo method (CMSY) for estimating fisheries reference points from catch, resilience and qualitative stock status information on data‐limited stocks. It also presents a Bayesian state‐space implementation of the Schaefer production model (BSM), fitted to catch and biomass or catch‐per‐unit‐of‐effort (CPUE) data. Special emphasis was given to derive informative priors for productivity, unexploited stock size, catchability and biomass from population dynamics theory. Both models gave good predictions of the maximum intrinsic rate of population increase r, unexploited stock size k and maximum sustainable yield MSY when validated against simulated data with known parameter values. CMSY provided, in addition, reasonable predictions of relative biomass and exploitation rate. Both models were evaluated against 128 real stocks, where estimates of biomass were available from full stock assessments. BSM estimates of r, k and MSY were used as benchmarks for the respective CMSY estimates and were not significantly different in 76% of the stocks. A similar test against 28 data‐limited stocks, where CPUE instead of biomass was available, showed that BSM and CMSY estimates of r, k and MSY were not significantly different in 89% of the stocks. Both CMSY and BSM combine the production model with a simple stock–recruitment model, accounting for reduced recruitment at severely depleted stock sizes. 相似文献
96.
Henning Lemche 《Journal of pest science》1937,13(5):57-60
Ohne Zusammenfassung 相似文献
97.
Henning K Sachse K Kirschen P Böhmer J Strutzberg-Minder K Grossmann E 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(1-2):1-7
The evaluation of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against chlamydiae in pig sera is described. The most widely used serological test is the complement fixation test (CFT). The CFT has a lack of sensitivity and specificity because of low antibody titers and unspecific reactions. Eight conventionally raised pigs were exposed to a pathogenic strain of Chlamydia suis, four controls were mock infected. The immune responses was monitored by CFT and indirect ELISA. There was no agreement between CFT and ELISA data. These results were confirmed by a study with 191 sera from nine pig farms. As shown by ELISA and PCR chlamydiae are widespread in swine. 相似文献
98.
我国黄土、褐土和潮土土壤中的氮素矿化潜力 总被引:4,自引:0,他引:4
在35℃下培养154天,用7、7、14、28、28、28、42天的培养间隔,测定了黄土、褐土和潮土16个土壤的氮素净矿化作用。培养前和每次间隔培养,土壤中的矿质氮用0.01 M CaCl2淋洗收集,应用紫外分光光度计测定每次淋洗液中的NO3-N。积累的净矿质氮与时间平方根t1、2呈线性相关。采用G. Stanford和S. J. Smith以及J. Richter的数学模型计算了每个土壤的氮素矿化潜力N6。结果表明,氮素矿化潜力能反映土壤的供氮能力,土壤氮素矿化潜力N0占土壤全氮百分数为10.8—23.4%。矿化速率常数k的最可靠估算为0.0064±0.0006日-1。 相似文献
99.
Modelling Ammonia Losses After Field Application of Biogas Slurry in Energy Crop Rotations 总被引:1,自引:0,他引:1
Dirk Gericke Lüder Bornemann Henning Kage Andreas Pacholski 《Water, air, and soil pollution》2012,223(1):29-47
Over the past few years the number of biogas slurries, which are generally used as nitrogen fertilisers, have seen a steady
increase in Germany. A mechanistic ammonia volatilisation model was developed to predict the ammonia losses of these slurries
when applied to bare soil, maize, wheat and rye grass canopies. Data for model development were collected from several field
measurements carried out at two locations in Northern Germany between the years of 2007 and 2008. Additionally, the behaviour
of the slurries on and in the soil was investigated through the use of infiltration pot experiments. The model includes three
main compartments: slurry, atmosphere and soil. The soil compartment model is relatively simple, as the slurry infiltration,
nitrification and ploughing dislocation into the soil determined in the experiments showed quantitatively no significant differences
between the tested slurries (mono-fermented, co-fermented and pig slurry) and soils (sand soil and loamy sand). Hence, instead
of a complex soil model, stable reduction factors, as derived from the experiments, were implemented in the model. Simulated
ammonia emissions were statistically compared (root mean square error (RMSE), modelling efficiency (ME), linear regression)
to the observed emissions. All evaluations showed an acceptable model performance (RMSE = 1.80 kg N ha−1), although there were a few number of anomalies which could not be modelled in an adequate way. A model sensitivity analysis
showed that temperature and slurry pH value are the main drivers of NH3 volatilization in the model. Following a change of +1°C or of +0.1 pH unit ammonia volatilization will increase by about
1% and 1.6% of the applied total ammoniacal nitrogen, respectively. We were able to show that a simple model approach could
explain most factors of ammonia volatilization in biogas crop rotations. 相似文献
100.
Klobasa F Schröder C Stroot C Henning M 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(1-2):19-23
603 neonatal piglets (German Landrace) were investigated for passive immunization affected by birth order, birth weight, litter size and parity. Concentrations of immunoglobulins in the blood serum of piglets on the first day of life served as measure for passive immunization. Blood samples were drawn at 12, 18 and 24 hours post partum. Quantitative measurements of immunoglobulin classes were carried out by radial immunodiffusion. There was a significant effect of birth order, because of the rapid changes in colostrum composition between onset of birth and the last piglet of each litter. The effect of birth weight was only partly significant and different for the immunoglobulin classes. There was no significant effect of litter size on passive immunization. Parity had a significant positive effect on IgG- and IgA-concentrations in sow's colostrum with litter two to six, parity 1 and 2 lead to highest IgM concentrations in the blood serum of piglets. 相似文献