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291.
OBJECTIVE: To describe removal of guttural pouch chondroids through a laser fenestrated mesial septum in a pony with an obstructed pharyngeal ostium of the left guttural pouch. STUDY DESIGN: Case report. ANIMALS: Pony. METHODS: Transendoscopic laser neodymium:yttrium aluminum garnet (Nd:YAG) fenestration of the mesial guttural pouch septum was made by contact method (bare fiber, 15-25 W, exposure time 4 seconds). Dissected tissue was removed by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and multiple chondroids of varying size were removed from the left guttural pouch through the fenestration. RESULTS: After removing all chondroids and repeated flushing of the left guttural pouch via the right side, inflammation of the guttural pouch membranes decreased remarkably. The pony was discharged with instructions for transendoscopic lavage once weekly and was reevaluated at 2 months. A permanent septal fenestration was observed and the pony was free of abnormal clinical signs and being used for carriage driving competitions. CONCLUSION: Nd:YAG laser fenestration of the mesial septum is an approach for access to guttural pouch chondroids. CLINICAL RELEVANCE: When guttural pouch empyema and/or chondroids is associated with adhesion of the pharyngeal ostium, laser fenestration of the mesial septum from the opposite guttural pouch should be considered as an alternative approach for access, rather than classic external surgical approaches.  相似文献   
292.
An epidemiological study on summer eczema (SE) was performed in 490 Icelandic horses from 24 stud farms located in Lower Saxony and Westphalia. The study revealed a prevalence of summer eczema of 29.8 %. Horses imported from Iceland were affected with a frequency of 71.9 %, whereas horses born in Germany and other countries had a prevalence of 15.6 % and 27.3 %. Mares (33.1 %) and geldings (29.1 %) were more often affected by summer eczema than stallions with 15.5 %. The most common sites of summer eczema were mane and tail. Five to eight years old horses were more severely affected by SE than younger or older horses. Piebald horses showed higher degrees of SE than grey horses. The high prevalence of SE in Icelandic horses kept in Germany was due to imported horses from Iceland particularly horses imported at an age of seven to 15 years were at an extremely high risk to SE (96.4 %). The prevalence of SE significantly increased with higher age. Chestnut and grey horses born in Germany were prone to a lower risk to SE than bay, black or piebald horses. In horses imported from Iceland, a higher inbreeding coefficient was significantly related to a lower prevalence of SE. The most efficient measure recommended for reduction of SE in Germany would be to abandon imports of Icelandic horse from Iceland.  相似文献   
293.
We report the historical, clinical and histopathological characteristics of skin lesions in biopsies from 37 heavy draught horses with chronic pastern dermatitis. The skin lesions were divided into four macroscopic groups: scaling (group I, n=5), hyperkeratotic and hyperplastic plaque-like lesions (group II, n=14), nodular skin masses (group III, n=16) and verrucous skin lesions (group IV, n=2). The principal histological findings were hyperkeratosis and epidermal hyperplasia. There was a gradual increase in epidermal hyperplasia from groups I to IV, suggesting that the lesions represent different stages of disease. In all cases, there was perivascular dermatitis dominated by T lymphocytes with an increase in MHC class II-positive dendritic-like cells. Immunohistochemical labelling for cytokeratins CK5/6(4), CK10 and CK14 indicated a change in their expression pattern. This correlated with the degree of epidermal hyperplasia, indicating abnormal differentiation of keratinocytes. There was a statistically significant correlation between the severity of skin lesions and several other factors including increasing age, increasing cannon circumference, prominence of anatomical structures such as fetlock tufts of hairs, ergots and chestnuts, and bulges in the fetlock region.  相似文献   
294.
Corneal esthesiometry in the healthy horse   总被引:1,自引:1,他引:0  
Objective To determine corneal sensitivity in healthy adult horses in order to establish reference values. Animals studied One hundred eyes of 50 healthy adult horses. Procedure Corneal sensitivity was determined by evaluating the corneal touch threshold (CTT) in five different corneal regions using a Cochet‐Bonnet esthesiometer. Results Comparing CTT values (in mm filament length) of the five prescribed corneal regions revealed regional variations in corneal sensitivity, with the central region (21.15 ± 6.23 mm) being the most sensitive, followed by the nasal (20.75 ± 5.14 mm), temporal (20.70 ± 5.37 mm), ventral (20.15 ± 5.88 mm) and dorsal (15.85 ± 3.70 mm) region. However, differences between the central, nasal, temporal and ventral regions were not statistically significant, whereas the dorsal region was significantly (P < 0.0001) less sensitive compared to the other regions. Division of the horses into three age groups revealed an insignificant decrease in corneal sensitivity with age in the nasal, temporal, ventral and central region, and an insignificant increase with age in the dorsal region. Correlation of corneal sensitivity with age was statistically significant in the central, ventral and temporal region. No statistically significant difference in the CTT was found between left and right eyes and between males and females. Conclusions CTT values in 100 eyes of 50 healthy adult horses evaluated with a Cochet‐Bonnet esthesiometer generated reference values. Reference values are necessary to determine alterations of corneal sensation accompanying various eye diseases or systemic diseases.  相似文献   
295.
The iron‐cyanide complexes ferricyanide, [FeIII(CN)6]3?, and ferrocyanide, [FeII(CN)6]4?, are anthropogenic contaminants in soil. We studied the interactions of ferricyanide with humic soils and charred straw (maize and rye, both charred at 300, 400 and 500°C) by batch experiments and Fourier transform infrared (FTIR) spectroscopy. All soil samples sorbed ferricyanide (up to 8.4 g kg?1). Precipitation of a manganese ferrocyanide after reduction of ferricyanide in the moderately acidic to neutral soils was deduced from both FTIR spectroscopy (CN absorption bands at 2069–2065 cm?1) and geochemical modelling. Ferricyanide was also adsorbed onto the charred straw. The amounts of iron‐cyanide complexes adsorbed increased with increasing charring temperature, with a maximum of 1.71 g kg?1. An absorption band at 2083 cm?1 indicated weakly adsorbed intermediates of the reduction of ferricyanide to ferrocyanide. This band disappeared in the samples charred at higher temperature, whereas a band at 2026 cm?1 was present in all spectra and became intensified in the high‐temperature straw. We attribute this band to ferrocyanide forming inner‐sphere complexes, presumably with quinone species of the organic matter. The band at 2026 cm?1 was also present in the spectra of the soils, indicating that soil organic matter also adsorbs ferrocyanide. However, in humic soils the main processes of ferricyanide interaction include reduction to ferrocyanide and precipitation as manganese ferrocyanide. Quantitatively, adsorption on highly aromatic substances plays only a less important role as compared with precipitation.  相似文献   
296.
OBJECTIVE: To assess the biological response to recombinant feline interferon-omega (rFeIFN-omega) following ocular or oral administration in cats via estimation of Mx protein expression in conjunctival cells (CCs) and WBCs. ANIMALS: 10 specific pathogen-free cats. PROCEDURES: In multiple single-dose drug experiments, each cat received various concentrations of rFeIFN-omega administered topically into both eyes (50 to 10,000 U/eye) and orally (200 to 20,000 units). The same cats received saline (0.9% NaCl) solution topically and orally as control treatments. The CCs and WBCs were collected prior to treatment (day 0), on day 1, and every third or seventh day thereafter until samples yielded negative results for Mx protein. Samples were examined for Mx protein expression via immunohistochemistry and immunoblotting procedures involving murine anti-Mx protein monoclonal antibody M143. RESULTS: After topical application of 10,000 U of rFeIFN-omega/eye, CCs stained for Mx protein for a minimum of 7 days, whereas WBCs were positive for Mx protein for a minimum of 31 days. After topical application of lower concentrations, CCs did not express Mx protein, in contrast to WBCs, which stained for Mx protein at 1,000 units for at least 1 day. Following oral administration, Mx protein was expressed in WBCs at rFeIFN-omega concentrations as low as 200 units, whereas CCs did not stain for Mx protein at any concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that Mx protein expression (a marker of the biological response to rFeIFN-omega) in CCs and WBCs of rFeIFN-omega-treated cats depends on the dose of rFeIFN-omega, site of administration, and cell type.  相似文献   
297.
298.
Farmers markets (FMs) have traditionally served as a space for farmers to sell directly to consumers. Recently, many FMs in the US and other regions have experienced a renaissance. This article compares the different value sets embedded in the rules and norms of two metropolitan FM regions—Minneapolis, Minnesota and in Vienna, Austria. It uses a values-based framework that reflects the relationships among FM operating structures (OS) and their values reflected by the key FM participants—i.e., farmer/vendors, consumers and market managers. The framework allows us to focus on two very contrasting value sets of metropolitan FM regions in (1) presenting and discussing the values found and embedded in the two metropolitan market regions; (2) illustrating how the values found are embodied as rules and norms in each FM region; (3) considering the alignment or not of FM participant values with their corresponding FM values; and (4) the differences and commonalities as well as the benefits and challenges of the two market regions. In contrasting metropolitan FMs we explain that FM value sets are complex and differ among and within FM participant groups and are dependent on their respective OS. We show that contrasting two metropolitan FM regions can be useful in understanding beneficial and disadvantageous relationships between the values and structures of, and in FMs, and specifically in examining institutional impediments such as governance. Thus we illustrate the possibilities and limitations of values for and within metropolitan FMs.  相似文献   
299.
An update of the 2006 American College of Veterinary Internal Medicine (ACVIM) Small Animal Consensus Statement on Lyme Disease in Dogs: Diagnosis, Treatment, and Prevention was presented at the 2016 ACVIM Forum in Denver, CO, followed by panel and audience discussion and a drafted consensus statement distributed online to diplomates for comment. The updated consensus statement is presented below. The consensus statement aims to provide guidance on the diagnosis, treatment, and prevention of Lyme borreliosis in dogs and cats.  相似文献   
300.

Background

Fungal pathogens like Fusarium graminearum can cause severe yield losses and mycotoxin contamination of food and feed worldwide. We recently showed its ability to systemically colonize wheat via root infection. However, the molecular response of wheat to Fusarium root rot (FRR) infection and systemic spread is still unknown. As a molecular camera, mass spectrometry (MS) imaging combines label-free and multiplex metabolite profiling with histopathology.

Results

Atmospheric-pressure (AP)-SMALDI-MS imaging was combined with optical microscopy to study wheat-F. graminearum interaction at the root–shoot junction, which is a crucial line of defense against a pathogen that can invade all distal plant parts. To scope the functional, temporal and local aspects of FRR disease spread, metabolic changes were simultaneous visualized in diseased and healthy stem bases of the resistant cultivar Florence-Aurore at 10, 14 and 21 days after root inoculation. Histological information was used to identify disease relevant tissues and to assist the interpretation of molecular images. Detected mycotoxin compounds secreted by F. graminearum showed a route of stem infection that was consistent with observations made by microscopy. The outer epidermis and vasculature of leaf sheath were, at different disease stages, identified as prominent sites of pathogen migration and wheat protection. Wheat metabolites mapped to these relatively small tissues indicated cell wall strengthening and antifungal activity as direct defenses as well as conservation in the wheat reactions to F. graminearum diseases that affect different plant organs.

Conclusions

AP-SMALDI-MS imaging at high spatial resolution is a versatile technique that can be applied to basic and applied aspects of agricultural research. Combining the technology with optical microscopy was found to be a powerful tool to gain in-depth information on almost unknown crop disease. Moreover, the approach allowed studying metabolism at the host–pathogen interface. The results provide important hints to an understanding of the complex spatio-temporal organization of plant resistance. Defense-on-demand responses to pathogen ingress were found, which provide opportunities for future research towards an improved resistance that does not negatively impact yield development in the field by saving plant resources and, moreover, may control different Fusarium diseases.
  相似文献   
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