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Abstract— On the basis of the evaluation of Beagle breeding records extending over a 8-year period dealing with one strain of English dogs and one of American dogs, criteria are pointed out which are of value when assessing the productivity of the total breeding station and of the individual bitch. These criteria form the basis of breeding and commercial planning. The question as to how long the individual bitch can remain productive for breeding and when she should be excluded from breeding for economic considerations is discussed. Résumé— Sur la base de données relatives à 8 années d'activité d'un chenil d'élevage de chiens Beagle de race anglaise et de race américaine, I'auteur définit divers critères permettant d'évaluer la productivité totale du chenil et celle de chaque chienne. Ces critères servent de base aux prévisions en matière de reproduction et de vente. L'auteur examine en outre la dude de vie utile de la chienne reproductrice et la durée de reproduction rentable. Zusammenfassung— Eine Auswertung von Protokollen der Spuerhundzuechtung (Beagle), die sich ueber einen Zeitraum von 8 Jahren erstrecken und je eine Zucht englischer und amerikanischer Hunde umfassen, ist die Basis von Kriterien, die alswervtoll fuer eine Abschaetzung der Produktivitaet sowohl einer gesamten Zuechterei als auch einer einzelnen Huendin aufgefuehrt werden. Diese Kriterien bilden die Grundlage fuer die Zucht und fuer die kommerzielle Planung. Die Frage, wielange eine einzelne Huendin fuer die Zuechtung produktiv bleiben kann und wann sie am wirtschaftlichen Gruenden vom Zuechten ausgeschlouen werden soll, wird behandelt.  相似文献   
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A decline in T-cell-mediated immunity and transient state of immunosuppression after immunization has been reported in dogs. Nevertheless, dogs are still routinely vaccinated with polyvalent live vaccines and severe disease does not generally occur. In order to investigate these effects on the canine immune system and to elucidate possible mechanisms we determined the following immune parameters in the blood of 33 clinically sound German shepherd dogs before and after standard vaccination with a polyvalent vaccine against distemper, parvovirus, viral hepatitis, leptospirosis, kennel cough and rabies: white and differential blood cell count, the serum concentrations and/or activities of IL-1, IL-2, IFN-gamma, TNF-alpha, neopterin and IgG, natural killer (NK) cell activity, bactericidal activity and complement hemolytic activity, lymphocyte proliferation test (LPT) and nitroblue tetrazolium test (NBT).Our major findings were that significant postvaccinal decreases in T-cell mitogenic response to PHA and in neutrophil function and neopterin serum concentration were accompanied by simultaneous increase in plasma IgG and hemolytic complement activity. This suggests a transient shift in the balance between cell-mediated and humoral (T(H)1/T(H)2) immunity rather than immunosuppression.These results do not imply that dogs should not receive live vaccines, as the response to vaccines just seems to create a state of altered homeostasis when immunization elicits protection by humoral and cell-mediated immunity. However, these recognized compromises of immune function should be considered and vaccines still be applied only in healthy animals and strictly according to the rules and regulations given by the manufacturer.  相似文献   
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The BVDV envelope glycoprotein E(rns)/gp48 and the C terminal 79 amino acids of the capsid protein coding region were expressed in a baculovirus system and antigenically characterized. Western blot assay was used to detect recombinant E(rns) (r-E(rns)) in infected insect cells using specific monoclonal antibodies. The r-E(rns) was then used in an indirect ELISA to detect BVDV specific antibodies in a panel of 540 well-characterized sera. Results of the r-E(rns) ELISA were compared to those obtained with a commercially available competitive ELISA targeting anti-NS2/3 antibodies. A good correlation was observed between the 2 ELISA (kappa = 0.916, 95% C.I.: 0.876, 0.956). Using the commercial NS2/3 ELISA as the reference test, the relative sensitivity of r-E(rns) ELISA was 97.5% (95% C.I.: 94.3%, 99.1%) and the relative specificity was 93.9% (95% C.I.: 89.4%, 96.9%), while relative specificity was 100% (95% C.I.: 97%, 100%) using true negative sera (derived from a negative herd). All but 1 antigen positive animals (n = 36) tested negative in the r-E(rns) ELISA; among them all 22 confirmed PI animals were negative by r-E(rns) ELISA. The ability of r-E(rns) ELISA to identify cattle immunized with inactivated vaccine was also demonstrated in a small group of cattle, compared to an NS2/3 antibody ELISA. Results suggest that r-E(rns) ELISA represents an alternative test for antibody generated by natural infection or BVDV vaccination.  相似文献   
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The chlorophyll fluorescence kinetics of ‘Jonagold’ and ‘Cox’ apples, stored under different conditions to induce mealiness, were measured. Three different storage conditions were considered causing three mealiness levels: not mealy, moderately and strongly mealy. Also destructive measurements of the texture (firmness, hardness, juice content and soluble solids content) were done. Classification into different mealiness levels based on the fluorescence measurements was more performant than a classification based on the destructive measurements. To estimate the mealiness level in a non-destructive way from the fluorescence features, a number of different classifiers were constructed. Quadratic discriminants and supervised and unsupervised neural networks were tested and compared. The self-organising map gives promising results when compared with the multi-layer perceptrons and quadratic discriminant analysis. The different advantages of the constructed classifiers suggest that fluorescence can be used in an automatic sorting line to assess certain types of mealiness.  相似文献   
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The aim of this work was to examine in vivo whether infection with Mycoplasma hyopneumoniae (M. hyop) and/or Mycoplasma flocculare (M. floc) would interact and influence the severity of enzootic pneumonia in piglets. Specific pathogen-free, hysterectomy-derived piglets were allocated to six groups and experimentally inoculated with M. hyop. and/or M. floc at the age of 2 or 8 weeks. Clinical symptoms, frequency of coughing and temperature measurement were noted daily. Lung lesions were recorded by post-mortem examination and histological observations. The cross-inoculation with both mycoplasmas did not influence the clinical or the pathological picture of the disease. Evolution of specific and crossreacting antibodies was analyzed by ELISA and immunoblotting. Animals inoculated with M. floc did not develop any lesions but showed a weak antibody response 6-8 weeks post-infection (p.i.). No cross-reacting antibodies against M. hyop proteins were detected. In animals inoculated with M. hyop, the first antibody response was detectable 4-5 weeks p.i. and was stronger in piglets infected at the age of 2 weeks than at the age of 8 weeks. Three cross-reacting antibodies against M. floc proteins with molecular weights of 110, 47 and 33 kDa were detected by antibodies to M. hyop. Experimental infections with both mycoplasmas did not show differences in the pattern of species-specific proteins.  相似文献   
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24-hour renal clearance and excretion of endogenous substances in the mare   总被引:1,自引:0,他引:1  
Urine samples were obtained from 6 healthy mares. During a 2-day acclimation period, mares were kept in stalls, fed sweet feed and mixed grass hay, and allowed free access to water and trace mineral salt. The mares were crosstied in their stalls within reach of hay, salt, and water for 24 hours during which urine was obtained by constant flow via indwelling Foley catheters. Twenty-four-hour urine production was 7,649 to 11,904 ml/day (mean = 9,212 +/- 1,9285) or 14.7 to 25.1 ml?/day. (mean = 19.3 +/- 4.1). Urinary excretion and clearance of electrolytes and protein were determined from aliquots of well-mixed, pooled 24-hour urine samples. These values were sodium (Na) = 0 to 1.7 mEq/kg/day (mean = 0.4 +/- 0.7), chloride (Cl) = 2.0 to 4.2 mEq/kg/day (mean = 3.0 +/- 0.8), phosphorous (P) = 0.03 to 0.12 mg/kg/day (mean = 0.07 +/- 0.3), potassium (K) = 3.7 to 6.5 mEq/kg/day (mean = 5.3 +/- 1.4), and creatinine (Cr) = 32.1 to 53.9 mg/kg/day (mean = 40.3 +/- 8.5). Fractional excretions of electrolytes were Na = 0% to 0.46% (mean = 0.1 +/- 0.2), Cl = 0.48% to 1.64% (mean = 1.14 +/- 0.45), P = 0.04% to 0.16% (mean = 0.08 +/- 0.04), and K = 23.9% to 75.1% (mean = 51.7 +/- 17.3). Average clearances (ml/hr/kg) were Na = 0.12 +/- 0.19, K = 64.1 +/- 17.1, Cl = 1.21 +/- 0.33, and P = 0.09 +/- 0.51. Average endogenous Cr clearance (ml/min/kg) was 1.92 +/- 0.51.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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