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排序方式: 共有169条查询结果,搜索用时 15 毫秒
101.
Schulz C Ritzmann M Palzer A Heinritzi K Zöls S 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(5-6):177-182
Since April 2006 piglets in Germany can only be castrated without anesthesia in the first 7 days of life. However, a castration is a painful experience even for an animal of this young age. Whether the castration under isoflurane-anesthesia is a reasonable alternative to castration without anesthesia was tested in the following investigation at 206 4 to 6 day old piglets.The serum-cortisol-concentration was chosen as the parameter for the pain caused by castration. A part of the animals was castrated without anesthesia (group II, n = 42) or with anesthesia (group IV, n = 41). Additionally Meloxicam, a non-steroidal anti-inflammatory drug, was applicated to piglets castrated with anesthesia (group V, n = 41). For control another part of the animals were only handled without (group I, n = 41) or with anesthesia (group III, n = 41), but they were not castrated. Cortisol-concentration prior to castration was compared to the concentration 0.5, 1,4 and 24 hours after castration. In addition cortisol was compared between groups at all points of time. Cortisol did rise significantly in castrated animals with animals with or without anesthesia than in animals of the non-castrated control groups. Cortisol after castration was significantly lower in piglets with an application of Meloxicam prior to castration. The pain caused by castration is an explanation for the differences in cortisol-concentration between castrated and not-castrated animals. Regarding those results, we assume that castration with isoflurane-anesthesia does not fulfil the demand for reducing pain after castration compared to castrating piglets without anesthesia. 相似文献
102.
Harvey RJ Depner UB Wässle H Ahmadi S Heindl C Reinold H Smart TG Harvey K Schütz B Abo-Salem OM Zimmer A Poisbeau P Welzl H Wolfer DP Betz H Zeilhofer HU Müller U 《Science (New York, N.Y.)》2004,304(5672):884-887
Prostaglandin E2 (PGE2) is a crucial mediator of inflammatory pain sensitization. Here, we demonstrate that inhibition of a specific glycine receptor subtype (GlyR alpha3) by PGE2-induced receptor phosphorylation underlies central inflammatory pain sensitization. We show that GlyR alpha3 is distinctly expressed in superficial layers of the spinal cord dorsal horn. Mice deficient in GlyR alpha3 not only lack the inhibition of glycinergic neurotransmission by PGE2 seen in wild-type mice but also show a reduction in pain sensitization induced by spinal PGE2 injection or peripheral inflammation. Thus, GlyR alpha3 may provide a previously unrecognized molecular target in pain therapy. 相似文献
103.
Cornelia Adlhoch Aleksandra Miteva Anna Zdravkova Tihana Miki Draen Kneevic Sokratis Perdikaris Krzysztof
mietanka Edyta
wito Vilem Kopriva Martin Chudý Luis Jose Romero Gonzlez Ines Moreno Gil Annica Walln Norell Frank Verdonck 《Zoonoses and public health》2019,66(7):874-878
We estimated that more than 11,000 people were exposed to highly pathogenic avian influenza viruses in EU/EEA countries over the outbreak period October 2016–September 2018 by cross‐linking data submitted by Member States to European Food Safety Authority and EMPRES‐i. A stronger framework for collecting human exposure data is required. 相似文献
104.
Mathieu Thevenot Marie-France Dignac Cornelia Rumpel 《Soil biology & biochemistry》2010,42(8):1200-1848
Lignins are amongst the most studied macromolecules in natural environments. During the last decades, lignins were considered as important components for the carbon cycle in soils, and particularly for the carbon storage. Thus, they are an important variable in many soil-plant models such as CENTURY and RothC, and appeared determinant for the estimation of the soil organic matter (SOM) pool-size and its stabilization. Recent studies challenged this point of view. The aim of this paper was to synthesise the current knowledge and recent progress about quantity, composition and turnover of lignins in soils and to identify variables determining lignin residence time. In soils, lignins evolve under the influence of various variables and processes such as their degradation or mineralization, as well as their incorporation into SOM. Lignin-derived products obtained after CuO oxidation can be used as environmental biomarkers, and also vary with the degree of degradation of the molecule. The lignin degradation is related to the nature of vegetation and land-use, but also to the climate and soil characteristics. Lignin content of SOM decreases with decreasing size of the granulometric fractions, whereas its level of degradation increases concomitantly. Many studies and our results suggest the accumulation and potential stabilization of a part of lignins in soils, by interaction with the clay minerals, although the mechanisms remain unclear. Lignin turnover in soils could be faster than that of the total SOM. Different kinetic pools of lignins were suggested, which sizes seem to be variable for different soil types. The mechanisms behind different degradation kinetics as well as their potential stabilization behaviour still need to be elucidated. 相似文献
105.
106.
The etiology of human periodontal disease has been the focus of considerable research, yet relatively little is known about the causative agents of companion animal periodontitis. In humans, Porphyromonas gingivalis, a black-pigmented anaerobic bacteria (BPAB), has been implicated as the primary periopathogen. It has been demonstrated that BPAB are also found in companion animal periodontal pockets. While some animal BPAB have been individually identified, a study to identify the most frequently isolated subgingival BPAB has not been completed using genetic tools. The objective of this work was to identify the types and relative frequencies of pigmented anaerobic bacteria found in the periodontal pockets of dogs. Porphyromonas salivosa, Porphyromonas denticanis (a novel species) and Porphyromonas gulae were found to be the most frequently isolated BPAB associated with canine periodontitis. 相似文献
107.
Cornelia J. M. Almekinders 《Potato Research》1992,35(4):433-442
Summary Three similar field experiments with five cultivars were carried out to evaluate the effect of a 5-hour extension of the natural
daylength and a 3-hour night break on flowering and TPS production in the warm tropics. Shoot length, number of inflorescence
positions per plant and number of flowers per inflorescence varied considerably between the experiments. In each experiment,
the supplementary photoperiods delayed cessation of shoot growth and thereby increased the orders of branching and the number
of inflorescence positions per plant. The photoperiod treatments significantly increased the number of flowers at the last
produced inflorescence positions, but not at other ones. Pollen production and quality, berry set, seed set and 100-seed weight
were not affected by the photoperiod treatments. TPS production was characterized by variability in flowering and low and
variable seed production per flower. 相似文献
108.
The analysis of sugars in soil at a molecular level may help to understand their origin and function. Gas chromatographic determination of individual sugars was applied to the litter layers and all mineral soil horizons of an acid forest soil under broad-leaved trees. Hydrolysis was carried out using trifluoroacetic acid (TFA). For GC analysis, the monosaccharide units were derivatised by reduction to alditols and subsequent acetylation. The results indicate a strong contribution of microbial-derived carbohydrates in the mineral soil (Ah to Cv horizons) compared to the litter layers (L, Of and Oh horizons). 相似文献
109.
Elton Mammadov Michael Denk Frank Riedel Karolina Lewinska Cezary Kaźmierowski Cornelia Glaesser 《Communications in Soil Science and Plant Analysis》2020,51(16):2111-2136
ABSTRACT This study aimed to predict soil properties using visible–near infrared (VIS-NIR) spectroscopy combined with partial least square regression (PLSR) modeling. Special emphasis was given to evaluating effect of pre-processing methods on prediction accuracy and important wavelengths. A total of 114 samples were collected and involved in chemical and spectral analyzes. PLSR model of each soil property was calibrated for all pre-processing methods using all samples, and leave-one-out cross-validation was used to make comparisons between them. Then, PLSR model of each best pre-processing method was calibrated using a 75% of all samples and correspondingly validated with the remaining a 25%. Model accuracy was evaluated based on coef?cient of determination (R2), root mean-squared errors (RMSE), and residual prediction deviations (RPD). The high correlation coefficients were found between the tested soil properties and reflectance spectra. The pre-processing methods considerably improved prediction accuracy and filtering methods outperformed linearization methods, and the latter outperformed normalization methods. The performance of cross-validation, calibration and independent validation was similar. An excellent prediction (RPD>2.5) model was obtained for soil organic carbon (SOC) and calcium-carbonate (CaCO3), good quantitative (2.0< RPD<2.5) prediction for sand, silt, and clay, fair prediction (1.4< RPD<1.8) for pH, and poor prediction (1.0< RPD<1.4) for hygroscopic water content (WC). Important wavelengths varied depending on soil property, but some wavelengths were common. This study can be a precursor to building a pioneering soil spectral database, calibrating satellite data, and hyperspectral image mapping of soils as well as digital soil mapping, environmental, and erosion modeling in the Caucasus Mountains. 相似文献
110.
Kristen L. Corselius Steve R. Simmons Cornelia B. Flora 《Agriculture and Human Values》2003,20(4):371-383
It is important to understandfactors that influence management decisionsthat determine the level of diversificationwithin cropping systems. Because of the widevariety of cropping systems within a region,our study focused on a single county (Marshall)in northwestern Minnesota. This county wasselected because it is in an area where farmerswere reevaluating their cropping practicesduring the 1990s in response to severe plantdisease outbreaks and economic stresses. Asurvey (n = 153) and follow-up interviews (n = 9)of representative farmers in Marshall Countyshowed that they were approaching theircropping systems management decisions underthese conditions through a dominant conceptualframework (scientific) and two secondaryconceptual frameworks (institutional andspiritual), which we termed mental causalmodels. The study illustrates the ways farmersdefine and make decisions affecting theircropping systems diversity under conditions ofagronomic and economic adversity. It alsochallenges agricultural professionals to expandtheir thinking about educational strategiesthat are sensitive to the varied perspectivesof farmers beyond just the scientific mentalcausal model. 相似文献