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101.
Abstract The three most common canine autoimmune blistering skin diseases (AISBD), bullous pemphigoid (BP), mucous membrane pemphigoid (MMP) and epidermolysis bullosa acquisita (EBA) have recently been separated based on clinical, histological and immunological grounds. The objectives of this study were to determine the isotype profiles of circulating autoantibodies in these dermatoses. Serum was collected from 5 dogs with BP, 15 with MMP and 11 with EBA. All sera were tested using an indirect immunofluorescence method using salt-split canine gingiva as substrate. Anti-basement membrane IgG autoantibodies were detected in all patients. Among the IgG autoantibodies, IgG1 and IgG4 were encountered most frequently, while IgG2 and IgG3 were uncovered in some dogs. IgE autoantibodies were detected more often than IgA or IgM autoantibodies in any of the three entities. The predominance of IgG1, IgG4 and IgE autoantibody isotypes in dogs with AISBD is very similar to the situation found in humans with the homologous diseases.  相似文献   
102.
The purpose of this study was to evaluate the efficacy of a topical formulation of selamectin in the treatment of cheyletiellosis in cats. Fifteen adult domestic cats from the same household with naturally occurring Cheyletiella sp. infestation were enrolled in the study. On each cat, 45 mg of selamectin was applied on days 0, 30, and 60. No other treatment or environmental decontamination was performed during the trial. On days 0, 30, 60, and 120, all cats were examined, epidermal debris was collected over the dorsal area of the body with flea combs for microscopic examination, and fecal flotations were done. Clinical signs had subsided by day 60 in all 15 cats and no signs of recurrence were apparent on follow-up 1 year later. All epidermal and fecal samples were negative by day 60. No adverse reactions were observed. Under the conditions of our study, topical selamectin was a practical and well-tolerated means of treatment for cheyletiellosis in cats.  相似文献   
103.
The efficacy of tilmicosin administered in the feed to control Actinobacillus pleuropneumoniae infections in pigs was evaluated through a multisite, multitrial study. For each of 6 trials, 48 pigs (stratified by weight and sex) were randomly assigned to 6 to 8 pens. Medicated feed containing tilmicosin (200 g/t) and unmedicated feed were randomly assigned at the pen level and were provided ad libitum from day −7 to trial termination (day 14). Seeder pigs (inoculated intranasally with A. pleuropneumoniae serotype 1 and showing signs of clinical disease) were introduced to each pen on day 0. Rates of death, gross lesions, and culture of A. pleuropneumoniae at necropsy, clinical scores, average daily gain in weight, and average body temperature were compared between the medicated and unmedicated pigs. Compared with the unmedicated pigs, significantly fewer (P < 0.05) pigs given tilmicosin had lesions typical of A. pleuropneumoniae or had A. pleuropneumoniae isolated from their tissues at necropsy. Together with a significant reduction (P < 0.05) in the average percentage of pneumonic lung involvement (both visually and by weight), there were reductions in the numbers of pigs with moderate and severe pneumonic lung lesions and with A. pleuropneumoniae associated mortality. With tilmicosin treatment, the average daily weight gain, daily temperature, abdominal appearance, attitude, and respiration were also significantly better (P < 0.05). The results of this study demonstrate the in vivo effectiveness of tilmicosin (200 g/t) in controlling pleuropneumonia among swine experimentally infected with A. pleuropneumoniae.  相似文献   
104.
Four alternative functions are used for fitting tree height and diameter growth models for mongolian oak. (Quercus mongolica Fisch. et Turcz.). The data set includes 1250 random trees and 755 dominant trees coming from 510 temporary plots. The resultsshow that the Richards function is the best model for predicting height. diameter at breast height (DBH) and dominant height from age. The average growth curve of dominant height is used as a guide curve for the construction of a site index table which is partially validated using an independent data set. The Mitscherlich function is the best model for estimating height and dominant height from DBH. (Responsible Editor: Chai Ruihai)  相似文献   
105.
From June to December, we determined the effects of variations in biochemical composition on delta(13)C of tree rings of 2-year-old oaks (Quercus petraea (Matt.) Liebl.) growing under semi-natural conditions, and the dependence of these effects of water stress during the growth season. Percent abundance, carbon concentration and delta(13)C were measured in holocellulose, lignin, extractive-free wood, starch and a water-soluble fraction. Relative concentrations of lignin and holocellulose in the extractive-free wood varied little during the season or in response to water stress, indicating that these compounds could not quantitatively explain the variations in whole-wood delta(13)C. Among all sampled tree rings, the relative concentration of each structural compound (holocellulose and lignin) accounted for less than 5% of the delta(13)C variability in whole wood. Variations in holocellulose and extractive-free wood delta(13)C between tree rings were almost identical (r > 0.95), whereas variations in lignin delta(13)C were less well correlated to these compounds. Whole-wood delta(13)C had a slightly altered isotopic signal compared with that of the structural compounds because of the presence of the extractive component. These results showed that variations in lignin delta(13)C and lignin concentration have little influence on extractive-free wood delta(13)C and whole-wood delta(13)C. Rather, holocellulose influences delta(13)C the most. Thus, we confirmed that, for climatic reconstruction from tree rings, removal of extractives by soxhlet is generally sufficient and sometimes unnecessary. Our findings also indicate that, in the case of rapid and severe water stress, the structural component did not accurately record the associated increase in delta(13)C because of dilution with previously formed organic matter and cessation of trunk growth. The effect of drought on carbon isotope ratios was more pronounced in the extractive compounds, making them good water stress indicators but only on a scale of days to months.  相似文献   
106.
The aggressive Eucalyptus leaf pathogen, Teratosphaeria destructans, causes widespread damage in tropical and subtropical Eucalyptus-growing regions of Indonesia, China, Thailand, East Timor, Vietnam, Lao, and South Africa. Little is known regarding the origin, pathways of dispersal, or reproductive biology of this pathogen. The aim of this study was to investigate the genetic structure of a global collection of T. destructans isolates. This was achieved by developing and using polymorphic microsatellite markers. Low genotypic diversity and a limited number of private alleles were found in all investigated populations, with the highest maximum diversity of 10.7% in isolates from South Sumatra. This supports the hypothesis that T. destructans was introduced to these regions. High levels of clonality were common in all populations, especially in isolates sampled from the recent disease outbreak in South Africa, which were all identical. The global collection of isolates grouped into three distinct clusters, corresponding largely to their sampled regions. Low levels of genotypic diversity, high levels of clonality, and strong geographic structure suggest independent introductions into all the sampled areas from an unknown source. The results imply that strict biosecurity measures are needed to avoid introductions of additional genotypes in these areas.  相似文献   
107.
Topical amitraz is the only approved treatment for CGD; however, it is not always effective or well tolerated. Extra-label use of amitraz, milbemycin oxime, ivermectin, and moxidectin may be effective therapeutical alternatives for dogs with resistant CGD or dogs that have an intolerance to the licensed amitraz protocol. It appears that oral administration of milbemycin oxime (1-2 mg/kg), ivermectin (400-600 micrograms/kg), and moxidectin (400 micrograms/kg) daily is a practical therapeutical alternative and would provide similar cure rates. Nevertheless, milbemycin oxime is expensive, ivermectin is potentially more toxic, and only limited information is available on moxidectin. The average treatment duration with these new regimens is 4 months, with an expected range of 3 to 10 months. Treatment should be administered daily for a minimum of 3 months and for at least 1 month after a series of negative skin scrapings. For chronic cases or cases that take a relatively long time to respond to therapy, 2 to 3 months of treatment beyond negative scrapings may be more appropriate. Dogs with CGD always approach clinical normalcy weeks to months before negative skin scrapings are obtained. All dogs respond at their own rate; as long as the skin scrapings at each visit show fewer mites, the current therapy should be continued for an additional month. If the mite count starts to increase, this may suggest that the treatment protocol is not being followed or it may be that the therapy chosen was suboptimally effective. Although CGD is still a disease that is not easily treated, the prognosis for dogs with this disorder has dramatically improved in the past few years. It must be remembered, however, that the treatment alternatives for CGD described above are not approved and should not be used unless the approved therapeutical regimen has failed.  相似文献   
108.
A premature foal developed severe aspiration pneumonia secondary to persistent dorsal displacement of the soft palate associated with marked edema of the larynx and nasopharynx. Tube esophagostomy was used successfully for long-term nutritional supplementation. There were no complications, and bypass of the larynx and pharynx allowed resolution of the palatal abnormality and subsequent resolution of the aspiration pneumonia. (Vet. Emerg. Crit. Care, 10:7–12, 2000)  相似文献   
109.
Sperm of gilthead seabream, Sparus aurata, was diluted with solutions of different osmolarities and pH. The effect of the different diluents on sperm motility (intensity and percentage of motile sperm) was studied. Motility was induced as early as 10 s after mixing the sperm with diluents having an osmotic pressure higher than 500 mOsm/l. The intensity of motility decreased when the osmotic pressure was reduced, and was zero or significantly inhibited when the osmotic pressure of the diluent (300–380 mOsm/l) was close to that of the fish's seminal plasma (364.6±3.03 mOsm/l). The pH of the diluent did not have any effect on sperm motility (in a range of 6.8 to 8.9). A diluent which prevents spermatozoa motility (osmotic pressure 375 mOsm/l and pH 7.35) was successfully used to cryopreserve S. aurata sperm at −196°C. This diluent is considered promising for the long-term preservation of gilthead seabream sperm.  相似文献   
110.
This study is the first to report nitrite occurrence and variability in surface water across an agricultural watershed in the province of Quebec, Canada. Nitrite (NO2 ?) concentrations were monitored across a 2.4 km2 watershed during 2 years. Water samples were collected at the outlet from April to November and in three contrasted stream branches (six stations) during three hydrological regimes (summer low water levels, fall recharge, and snowmelt). Our study clearly demonstrates that NO2 ? levels observed at the outlet are not representative of NO2 ? variability across the micro-watershed. Surface water collected in cropped areas presents high NO2 ? concentrations during summer low water levels, often exceeding guidelines for aquatic life, with NO2 ? means ranging from 0.022 to 0.107 mg N L?1 and maximum value reaching 0.156 mg N L?1. Furthermore, the two stream branches in cropped area have demonstrated significant differences in NO2 ? concentrations and other water quality parameters. The importance of groundwater discharge to streams in the micro-watershed Bras d’Henri may potentially generate different in-stream sources of NO2 ? and water quality parameters. However, further studies are essential to determine sources and processes related to in-stream NO2 ? peaks.  相似文献   
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