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991.
Recent finding suggests that T-cells may be involved in the pathogenesis of heaves in horses. However, little is known concerning their possible contribution to pulmonary neutrophilia, a characteristic finding in heaves. Interleukin (IL)-17 is a cytokine secreted by activated T-cells that indirectly promotes the maturation, chemotaxis and activation of neutrophils. We therefore hypothesized that IL-17 may be involved in the recruitment of neutrophils into the airways and that its mRNA expression would be increased in bronchoalveolar lavage (BAL) cells of horses with heaves. Heaves susceptible horses (n=4) and control horses (n=4) when in pasture (clinical remission) and after 35 days of continuous exposure to moldy hay were studied. BAL and respiratory mechanics measurements were performed at both time periods. The mRNA expression of IL-17 in BAL was studied using real-time polymerase chain reaction (PCR) and CD3-zeta was used as a marker of T-cell numbers. There was no significant difference in IL-17 mRNA expression between groups of horses while in pasture. However, stabling resulted in an increased expression of IL-17 in all horses with heaves but in none of the control horses. These preliminary results suggest that IL-17 may contribute in the pathogenesis of horses with heaves following chronic antigen challenge.  相似文献   
992.
This paper discusses the effects of breakwaters on the Rimini coastal environment over the last half century. Sediment cores of 50 cm thick were collected in various seasons from 2002 to 2005 and were subsampled at surface and subsurface levels at 20 inshore and offshore stations in order to take account of various freshwater and wastewater inputs. A 240-cm sediment core was collected in the most impacted area in order to reconstruct the evolution of the marine ecosystem since the time of the breakwaters’ construction. Sediment grain size, physico-chemical parameters, nutrients and inorganic and organic contaminants were determined. The breakwaters have stopped coastal erosion but have given rise to a worsening of environmental quality. No impacts were detected outside the breakwaters. The integrated approach, using biogeochemical markers to reconstruct spatial and historical environmental trends within the sheltered area, proved to be very useful in highlighting its capacity for recovery and providing indications for coastal management.  相似文献   
993.
994.
The world-wide increase of antimicrobial resistance in micro-organisms complicates medical treatment of infected humans. We did a risk-factor analysis for the prevalence of antimicrobial resistant Campylobacter coli on 64 Swiss pig finishing farms. Between May and November 2001, 20 faecal samples per farm were collected from the floor of pens holding finishing pigs shortly before slaughter. Samples were pooled and cultured for Campylobacter species. Isolated Campylobacter strains were tested for resistance against selected antimicrobials. Additionally, information on herd health and management aspects was available from another study. Because data quality on the history of antimicrobial use on the farms was poor, only non-antimicrobial risk factors could be analysed. Statistical analyses were performed for resistance against ciprofloxacin, erythromycin, streptomycin, tetracycline, and for multiple resistance, which was defined as resistance to three or more antimicrobials. Risk factors for these outcomes – corrected for dependency of samples at herd level – were analysed in five generalised estimation-equation models. Prevalence of antimicrobial resistance among Campylobacter isolates was ciprofloxacin 26.1%, erythromycin 19.2%, streptomycin 78.0%, tetracycline 9.4%, and multiple resistance 6.5%. Important risk factors contributing to the prevalence of resistant strains were shortened tails, lameness, skin lesions, feed without whey, and ad libitum feeding. Multiple resistance was more likely in farms which only partially used an all-in-all-out system (OR = 37), or a continuous-flow system (OR = 3) compared to a strict all-in-all-out animal-flow. Presence of lameness (OR = 25), ill-thrift (OR = 15), and scratches at the shoulder (OR = 5) in the herd also increased the odds for multiple resistance. This study showed that on finishing farms which maintained a good herd health status and optimal farm management, the prevalence of antimicrobial resistance was also more favourable.  相似文献   
995.
996.
997.
We received 190 reports of suspected adverse events (SARs) following the use of veterinary drugs for the year 2006: 118 declarations for veterinary drugs and 72 declarations following the application of immunolgical medicinal products. Most of the 118 declarations relate to the use of antiparasitic drugs (48%) and every second declaration to drug use in dogs. Other drug classes concerned were, in decreasing order, antiinfectives (20%) and drugs used off-label (12%; other target species or other indication). For the vaccines, most of the reactions occurred in dogs (62%) followed by horses (11%) and cattle (10%). The most frequently reported reactions concerned the use of a vaccine against piroplasmosis. Another 349 requests for information were processed by the Swiss Toxicological Information center. We also present a case of a serious adverse reaction in form of a Stevens-Johnson syndrome in a cat as well as a case of ketamine abuse. We note the growing interest of practicing veterinarians with pleasure and are currently working on further adaptations to the system.  相似文献   
998.
K. K. Nkongolo    K. C. Armstrong    A. Comeau    C. A. St.  Pierre 《Plant Breeding》1992,109(2):123-129
Common wheat × hexaploid triticale hybrids were produced and evaluated for tolerance to barley yellow dwarf virus disease (BYD). The BYD tolerance expression varied with wheat × triticale combination. The selection for BYD tolerance increased the recovery of tolerant genotypes in the next generations. Homozygous tolerant and susceptible lines were obtained in advanced generations. The rye chromosomes 1R, 2R, and 4R with 7R were transmitted as disomic or monosomic, disomic, and double disomic substitution to the late generations of ‘Musala’ (common wheat) בMuskox 658’ (triticale), ‘Encruzilhada’ (common wheat) בNord Kivu’ (triticale) and ‘Encruzilhada’× 12th. International Triticale Screening Nursery 267 (12ITSN267) (triticale), respectively. A clear association was established between the 1R chromosome of the ‘Muskox 658’ triticale line and the tolerance to BYDV. Results suggest that the 2R chromosome may be involved in BYD tolerance of ‘Nord Kivu’ triticale line.  相似文献   
999.
1000.
The non-covalent interactions between the monomeric phenolic compound chlorogenic acid (5-CQA) and bovine serum albumin (BSA), lysozyme, and alpha-lactalbumin were characterized, and their effect on protein properties was examined. 5-CQA had a low affinity for all three proteins, and these interactions seemed to show a negative cooperativity. 5-CQA-BSA binding decreased with increasing temperature, whereas pH (pH 3.0 compared to pH 7.0) and ionic strength had no pronounced effect. At high 5-CQA/protein molar ratios, both the denaturation enthalpy and temperature of BSA increased; however, covalent bonds were created at high temperatures. The presence of 5-CQA had no effect on the solubility of BSA and alpha-lactalbumin as a function of pH, whereas it decreased lysozyme solubility at alkaline pH due to covalent interactions. These results indicate that the non-covalent interactions with 5-CQA do not have pronounced effects on the functional properties of globular proteins in food systems.  相似文献   
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