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81.
82.
This study evaluated the effects of globin and spray-dried porcine plasma (SDPP) on growth performance, digestibility, nitrogen retention, energy retention efficiency (ERE) and intestinal morphology of broiler chickens. A total of 336-day-old male broiler chickens were reared from 1 to 40 days of age and fed 3 diets (8 replicates/diet, 14 birds/replicate) during 3 feeding phases: starter (1–12 days), grower (12–25 days) and finisher (25–40 days). Isonitrogenous diets were formulated by replacing gluten protein isolate contained in the control diet (C diet) with 2% (starter) or 1% (grower and finisher) spray-dried porcine plasma in the plasma diet (SDPP diet). The globin diet (G diet) was obtained by adding globin on the top of C diet at a dose of 0.08% for the whole rearing period. Total tract apparent digestibility (aD), nitrogen retention and ERE were assessed during the three growing phases. At 12  and 40 days of age, one bird per pen was slaughtered to sample gut, liver, spleen and bursa of Fabricius for histomorphological investigations. The SDPP diet increased body weights of chickens at 12 (+60 g; p < .001), 25 (+101 g; p < .001) and 40 days (+130 g; p = .018) of age compared to C and G diets. Also SDPP improved crude protein aD (+9.7%) and ERE (+12.3%) during the starter phase (p < .001). Dietary globin and SDPP inclusion did not affect either the gut morphology or the histopathological findings in birds at 12 and 40 days of age, despite a numerical (+6.90% and +7.40% respectively) villus height improvement in the SDPP group. Overall, these results confirm that dietary supplementation with SDPP and, to a lesser extent, with globin can improve growth performance and dietary protein and energy utilization in broiler chickens without effect on gut functionality.  相似文献   
83.
Point-of-care analyzers (POCAs) for quantitative assessment of bile acids (BAs) are scarce in veterinary medicine. We evaluated the Fuji Dri-Chem Immuno AU10V analyzer and v-BA test kit (Fujifilm) for detection of feline and canine total serum BA concentration. Results were compared with a 5th-generation assay as reference method and a 3rd-generation assay, both run on a bench-top analyzer. Analytical performance was assessed at 3 different concentration ranges, and with interferences. For method comparison, samples of 60 healthy and diseased cats and 64 dogs were included. Linearity was demonstrated for a BA concentration up to 130 µmol/L in cats (r = 0.99) and 110 µmol/L in dogs (r = 0.99). The analyzer showed high precision near the lower limit of quantification of 2 µmol/L reported by the manufacturer. Intra- and inter-assay coefficients of variation were < 5% for both species and all concentrations. Interferences were observed for bilirubin (800 mg/L) and lipid (4 g/L). There was excellent correlation with the reference method for feline (rs = 0.98) and canine samples (rs = 0.97), with proportional biases of 6.7% and −1.3%, respectively. However, a large bias (44.1%) was noted when the POCA was compared to the 3rd-generation assay. Total observed error was less than total allowable error at the 3 concentrations. The POCA reliably detected feline and canine BA in clinically relevant concentrations.  相似文献   
84.
Salinity risks on calcareous soils following pig slurry applications   总被引:2,自引:0,他引:2  
Abstract. The electrical conductivity of pig slurry suggests that addition of this waste to soils in arid and semi-arid areas could cause salinization. Changes in electrical conductivity and soluble salt concentration in two calcareous soils indicated a salinity risk after 24 months of pig slurry addition at rates of 400 m2/ha/yr or more. Salinity risk increased with soil water-holding capacity. Water-soluble potassium concentrations showed a greater increase than other cations in the soils because of the large amount present in the slurry. The proportion of soluble potassium in the soil depended on the soil's cation exchange capacity and on the composition of the clay fraction.  相似文献   
85.
According to the biphasic model of growth response to salinity, growth is first reduced by a decrease in the soil osmotic potential (Ψo), i.e., growth reduction is an effect of salt outside rather than inside the plant, and genotypes differing in salt resistance respond identically in this first phase. However, if genotypes differ in Na+ uptake as it has been described for the two maize cultivars Pioneer 3906 and Across 8023, this should result in differences in Na+ concentrations in the rhizosphere soil solution and thus in the concentration of salt outside the plant. It was the aim of the present investigation to test this hypothesis and to investigate the effect of such potential differences in soil Ψo caused by Na+ exclusion on plant water relations. Sodium exclusion at the root surface of intact plants growing in soil was investigated by sampling soil solution from the rhizosphere of two maize cultivars (Across 8023, Pioneer 3906). Plants were grown in a model system, consisting of a root compartment separated from the bulk soil compartment by a nylon net (30 μm mesh size), which enabled independent measurements of the change of soil solution composition and soil water content with increasing distance from the root surface (nylon net). Across 8023 accumulated higher amounts of sodium in the shoot compared to the excluder (Pioneer 3906). The lower Na+ uptake in the excluder was partly compensated by higher K+ uptake. Pioneer 3906 not only excluded sodium from the shoot but also restricted sodium uptake more efficiently from roots relative to Across 8023. This was reflected by higher Na+ concentrations in the rhizosphere soil solution of the excluder 34 days after planting (DAP). The difference in Na+ concentration in rhizosphere soil solution between cultivars was neither due to differences in transpiration and thus in mass flow, nor due to differences in actual soil water content. As the lower Na+ uptake of the excluder (Pioneer 3906) was only partly compensated by increased uptake of K+, soil Ψo in the rhizosphere of the excluder was more negative compared to Across 8023. However, no significant negative effect of decreased soil Ψo on plant water relations (transpiration rate, leaf Ψo, leaf water potential, leaf area) could be detected. This may be explained by the fact that significant differences in soil Ψo between the two cultivars occurred only towards the end of the experiment (27 DAP, 34 DAP).  相似文献   
86.
Normal mixtures are applied in interval mapping to model the segregation of genotypes following Mendel's Law in successive generations of crossing. Standard methods use least squares or maximum likelihood estimates. Theoretically, maximum likelihood is known to result in more efficient estimates than least squares. In the interval mapping literature, some authors state that both methods yield equivalent results, whereas other authors emphasize the higher efficiency of maximum likelihood. The present paper investigates differences of both methods more closely. We show by example the occurrence of multiple LOD-Score profiles when applying maximum likelihood estimation methods for a basic interval mapping and composite interval mapping model. This analysis results in some peaks of the LOD-Score profile that distinctly differ from F-statistic profiles without being spurious. A spurious profile for IM and CIM was found as well. It is concluded that users of IM and CIM mapping software must be prepared for the rare occurrence of spurious solutions in LOD profiles. The example indicates that especially in sparse marker maps maximum likelihood estimation has a potential to result in non-spurious profiles that are not similar to the F-statistic profiles. However, the discrimination of spurious and non-spurious further profiles is not straightforward in applications. Until the mathematical background of this phenomenon is investigated more thoroughly and rules to ascertain the information content of these additional solutions have been developed, the simultaneous use of the least squares and ML methods may caution against the rare occurrence of spurious results. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
87.
Precision Agriculture - Information provided by satellite data is becoming increasingly important in the field of agriculture. Estimating biomass, nitrogen content or crop yield can improve farm...  相似文献   
88.
A cross-sectional study involving 147 pig farms across England was conducted in 2008-2009. Farm severity of post-weaning multi-systemic wasting syndrome (PMWS) was estimated through the use of an algorithm that combined data on post-weaning mortality, PMWS morbidity and proportion of porcine circovirus type 2 PCR positive pigs. Farms were classified as non/slightly, moderately or highly affected by PMWS. Data on potential PMWS risk factors were collected through interviews, on-farm assessment and serological sampling. Risk factors were identified using multivariable ordinal logistic regression and multivariable linear regression. Factors associated with increased PMWS severity were rearing growers indoors (OR=23.7), requiring a higher number of veterinarian visits per year (OR=9.6), having poorly isolated hospital pens (OR=6.4), buying replacement boars (OR=4.8) and seropositivity to Mycoplasma hyopneumoniae (OR=4.29); factors associated with decreased PMWS severity were low stocking density for growers (OR=0.07), adjusting diets at least three times between weaning and 14 weeks of age (OR=0.12), and requiring visitors to be at least 2 days pig free (OR=0.14). This study provides evidence of the association between environmental and management factors and PMWS severity, and suggests that other pathogens may be important co-factors for the disease. In addition, this study highlights the potential efficacy of biosecurity measures in the reduction/prevention of within-farm PMWS severity.  相似文献   
89.
Saliva flow induced by 6-gingerol (pungent), hydroxy-α/β-sanshools (tingling), and citric acid (sour) was measured, and the time-dependent changes in the whole saliva proteome were analyzed by means of 2D-PAGE, followed by tryptic in-gel digestion and MALDI-TOF-MS peptide mass fingerprint analysis. The proteins showing significantly decreased abundance after oral 6-gingerol stimulation were identified as glutathione S-transferase P, the heat shock protein β-1, the heat shock 70 kDa protein 1, annexin A1, and cytoplasmic β-actin, whereas prolactin inducible proteins (PIP), short palate, lung and nasal epithelium carcinoma-associated protein 2 (SPLUNC2), zinc-α-2-glycoproteins (Zn-α-GP), and carbonic anhydrase VI (CAVI) were found with increased abundance. As the effects of this study were observed instantaneously upon stimulation, any proteome modulation is very likely to result from the release of proteins from preformed vesicles and not from de novo synthesis. The elevated levels of SPLUNC2, Zn-α-GP, and CAVI might be interpreted to trigger innate protective mechanisms in mucosal immunity and in nonimmune mucosal defense and might play an important role during the initial stage of inflammation.  相似文献   
90.
Intermittent administration of parathyroid hormone (PTH) is an anabolic therapy for osteoporotic conditions in humans. This study evaluated the effects of equine PTH fragment (ePTH-1-37) administration on bone metabolism in 12 healthy horses. Six horses each were treated once daily for 120days with subcutaneous injections of 0.5μg/kg ePTH-1-37 or placebo. Blood was collected to determine ionized calcium (Ca(++)), total Ca (Ca(T)), inorganic phosphorus, serum equine osteocalcin (eOC), carboxy-terminal telopeptide of type I collagen (ICTP), bone-specific alkaline phosphatase, and carboxy-terminal cross-linked telopeptide of type I collagen. Bone mineral density (BMD) was determined with dual X-ray absorptiometry of the metacarpus and calcaneus. Significantly higher blood Ca(++) and plasma Ca(T) concentrations were measured 5h after ePTH-1-37 administration compared to placebo. Higher serum eOC concentrations were found for ePTH-1-37 treatment at days 90 (P<0.05) and 120 (P=0.05). Significantly higher serum ICTP levels were observed with ePTH-1-37 treatment at days 60 and 90. For both study groups, BMD increased significantly in the calcaneus. Long-term use of ePTH-1-37 seemed to have no negative effects on bone metabolism in healthy horses. The absence of undesirable side effects is the premise to ensure safety for further clinical investigations in horses with increased bone resorption processes.  相似文献   
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