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Facial abscessation and osteomyelitis due to dental disease is commonly seen in the Malayan tapir (Tapirus indicus), but little is known about the prevalence or etiology of these lesions. To determine the prevalence of dental ailments, 56 skulls and mandibles of deceased Malayan tapirs were visually and radiographically evaluated. Dental lesions were scored according to severity, and individuals were classified according to their age (juvenile/ young adult/adult) and origin (captive/free ranging). All of the lesions identified were of a resorptive nature. seemingly originating at the cementoenamel junction and burrowing towards the center of the tooth. Overall, 27% of the investigated skulls presented radiolucent dental lesions. The prevalence among captive animals was 52% (13/25), while only 6% (2/31) of the free-ranging tapirs had dental lesions. The second, third, and fourth premolars and first molar were the teeth most commonly affected, and the mandibular teeth were more often involved than the maxillary dentition. This study demonstrates a high prevalence of resorptive dental lesions in captive Malayan tapirs and provides a strong indication that age and captivity are significant risk factors in the development of these lesions. Dental disease, Malayan tapir, radiology, resorptive lesions, Tapirus indicus.  相似文献   
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The oxidation in aqueous dispersions of egg yolk powder and the influence of addition of the proposed antioxidants ascorbic acid and ascorbic acid 6-palmitate indicate that both ascorbic acid and ascorbic acid 6-palmitate propagated the oxidation of egg yolk powder dispersions. Ascorbic acid 6-palmitate was found to be more prooxidative than ascorbic acid. Moreover, it was found that addition of ascorbic acid or ascorbic acid 6-palmitate gave rise to an increase in the amount of free iron Fe(II) in the egg yolk dispersions. It is proposed that ascorbic acid and ascorbic acid 6-palmitate react with the phosvitin-Fe(III) complex found in egg yolk and release Fe(II), which subsequently propagates lipid oxidation. It appears that less oxidation occurs in egg yolk dispersions exposed to high concentrations of peroxy radicals with added ascorbic acid than egg yolk dispersions with added ascorbic acid without exposure to peroxy radicals.  相似文献   
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Analyses of the spatial and temporal variations in the natural abundance of 13C are frequently employed to study transformations of plant residues and soil organic matter turnover on sites where long continued vegetation with the C3-type photosynthesis pathway has been replaced with a C4-type vegetation (or vice versa). One controversial issue associated with such analyses is the significance of isotopic fractionation during the microbial turnovers of C in complex substrates. To evaluate this issue, C3-soil and quartz sand were amended with maize residues and with faeces from sheep feed exclusively on maize silage. The samples were incubated at 15 °C for 117 days (maize residues) or 224 days (sheep faeces). CO2 evolved during incubation was trapped in NaOH and analysed for C isotopic contents. At the end of incubation, 63 and 50% of the maize C was evolved as CO2 in the soil and sand, respectively, while 32% of the faeces C incubated with soil and with sand was recovered as CO2. Maize and faeces showed a similar decomposition pattern but maize decomposed twice as fast as faeces. The δ13C of faeces was 0.3‰ lower than that of the maize residue (δ13C −13.4‰), while the δ13C of the C3-soil used for incubation was −31.6‰. The δ13C value of the CO2 recovered from unamended C3-soil was similar or slightly lower (up to −1.5‰) than that of the C3-soil itself except for an initial flush of 13C enriched CO2. The δ13C values of the CO2 from sand-based incubations typically ranged −15‰ to −17‰, i.e. around −3‰ lower than the δ13C measured for maize and faeces. Our study clearly demonstrates that the decomposition of complex substrates is associated with isotopic fractionation, causing evolved CO2 to be depleted in 13C relative to substrates. Consequently the microbial products retained in the soil must be enriched in 13C.  相似文献   
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Cytokines have been associated with the progression of congestive heart failure (CHF) in humans and may be implicated in the pathophysiology of myxomatous mitral valve disease (MMVD) in dogs. The aim of this study was to determine the serum concentrations of cytokines in dogs with MMVD. The study included 16 Cairn terriers with no or minimal mitral regurgitation (MR), 41 Cavalier King Charles Spaniels (CKCS) with different degrees of MR and 11 dogs of different breeds with CHF due to MMVD. Granulocyte-macrophage colony-stimulating factor, interferon-γ, interleukin (IL)-2, IL-6, IL-7, IL-8, IL-10, IL-15, IL-18, keratinocyte-derived chemokine, interferon-γ-induced protein and monocyte chemoattractant protein-1 (MCP-1) were measured using a canine-specific multiplex immunoassay. CHF dogs had significantly higher MCP-1 concentrations than dogs with no or minimal MR. Among the CKCS, IL-2 and IL-7 decreased with increasing left atrial size and IL-7 also decreased with increasing MR. IL-8 decreased with increasing left ventricular end-systolic internal dimensions. MCP-1 was increased in CHF dogs compared to healthy control dogs and IL-2, IL-7 and IL-8 decreased with increasing indices of disease severity. The results suggest a role for these cytokines in canine MMVD and CHF.  相似文献   
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The dog is widely used as a translational experimental model studying the host response and new treatments for human endotoxemia. The present study evaluated the applicability of a novel patient-near neutrophil chemiluminescence assay for the measurement of endotoxin activity in human blood when applied to canine blood samples. The assay was observed to be analytically sensitive and specific to endotoxin when tested in vitro, spiked with purified Escherichia coli lipopolysaccharide and live E. coli. The diagnostic sensitivity was sustained during Gram-positive contamination. Finally, it also demonstrated diagnostic potential when able to discriminate dogs with spontaneously occurring endotoxemia from both healthy dogs and diseased dogs without endotoxemia. The rapid patient-near assessment of endotoxin activity in canine blood should facilitate future studies on endotoxemia in both spontaneous disease and in experimental settings.  相似文献   
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Background: Low‐molecular‐weight heparin (LMWH) is being used increasingly in veterinary medicine for both treatment and prophylaxis of thromboembolic disease, but no predictable patient‐side method exists to monitor its effect. Objectives: The aim of this study was to evaluate thromboelastography (TEG) and prothombinase‐induced clotting time (PiCT) assays for detecting hemostatic alterations following in vitro heparinization of canine whole blood with dalteparin (Fragmin). Methods: Citrated whole‐blood samples were collected from 7 clinically healthy dogs. Dalteparin was added at concentrations of 0, 0.156, 0.625, 1.25, and 2.5 U/mL of whole blood. TEG was performed using heparinase cups with tissue factor (TF, 1:50,000) and kaolin as activators. Reaction time (R), clotting time (K), angle (α), and maximum amplitude (MA) were recorded. PiCT and anti‐FXa activity were measured in plasma. Results: With TF, increasing concentrations of dalteparin significantly prolonged R and K and significantly decreased α and MA. K, α, and MA ratios were significantly different from baseline at all dalteparin concentrations and R was significantly different from baseline at concentrations of 0.625, 1.25, and 2.5 U/mL. With kaolin, only R was significantly different from baseline at dalteparin concentrations of 0.625 and 2.5 U/mL. PiCT detected dalteparin concentrations ≤ 0.625 U/mL, with a good linear correlation (r2=.96, P<.0001). Conclusion: These results suggest that TF‐activated TEG and PiCT assays should be further evaluated as promising new methods for evaluating the effect of LMWH, using doses in the recommended clinical range and prospective clinical studies.  相似文献   
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