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91.
In order to implement best environmental management practices in agricultural watershed, it is necessary to evaluate non point source pollution loads and identify critical watershed pollution sources, which are regional management priority missions. Nutrient related non point source pollutant inputs can increase primary production and intensify water eutrophication. Not all watershed areas are critical and responsible for high amount nutrient pollution losses. Implementation of watershed environmental prevention is required to assess pollution yields. Further more, identification of these critical areas is essential for the effective and efficient implementation of watershed best environmental management. In this study, a geographic information system based Soil and Water Assessment Tool was applied in Bahe River watershed, a part of the Yangtze River basin. Land use, soil series texture and daily rainfall data for a 10-year period (1996–2005) was used in this study. The calibrated model system was verified to estimate average annual Organic Nitrogen and Organic Phosphorus yields in these 10 years. The estimated results were also tested and optimized by statistical software. Based on 10-year average yearly Organic Nitrogen yield and Organic Phosphorus losses, critical sub-watersheds were identified. The five sub-watersheds in the north part of watershed were under more intensive pollution yield, west group sub-watersheds contributed to moderate losses, whereas other sub-watersheds fell under slight loading classes. The research outputs developed a basis for an effective watershed environmental management plan. The study revealed that the Soil and Water Assessment Tool could be applied successfully for identifying critical sub-watersheds for watershed best environmental management purposes.  相似文献   
92.
A broad array of in vitro and in vivo assays has consistently demonstrated that glyphosate and glyphosate-containing herbicide formulations (GCHF) are not genotoxic. Occasionally, however, related and contradictory data are reported, including findings of mouse liver and kidney DNA adducts and damage following intraperitoneal (ip) injection. Mode-of-action investigations were therefore undertaken to determine the significance of these contradictory data while concurrently comparing results from ip and oral exposures. Exposure by ip injection indeed produced marked hepatic and renal toxicity, but oral administration did not. The results suggest that ip injection of GCHF may induce secondary effects mediated by local toxicity rather than genotoxicity. Furthermore, these results continue to support the conclusion that glyphosate and GCHF are not genotoxic under exposure conditions that are relevant to animals and humans.  相似文献   
93.
Electrophoresis in polyacrylamide gels was used to identify isoenzymes of serum alkaline phosphatase in sheep. Skeletal isoenzyme predominated in the serum of lambs and liver, skeletal and intestinal isoenzymes were found in the serum of adult ewes. In r ewes (R-r-i blood group system) intestinal isoenzyme activity was 67 per cent of total serum activity; in R ewes intestinal activity was only 36 per cent of total activity. Relative activities of the three isoenzymes differed greatly within individual ewes and between individual ewes during pregnancy and lactation.  相似文献   
94.
Control of α-mannosidosis in Angus cattle   总被引:1,自引:0,他引:1  
Tests for the detection of animals heterozygous for alpha-mannosidosis were undertaken on samples taken from 34,203 cattle registered with the Angus Society of Australia. Results indicates 1,836 (5.4%) of the animals were heterozygotes. Heterozygotes were detected in 214 (51%) of the herds examined.  相似文献   
95.
European bat lyssavirus type 2 (EBLV-2) has been isolated once previously from a bat in the UK in June 1996. In September 2002, a Daubenton's bat (Myotis daubentonii) found in Lancashire developed abnormal behaviour, including unprovoked aggression, while it was in captivity. Brain samples from the bat were tested for virus of the Lyssavirus genus, which includes EBLV-2 (genotype 6), and classical rabies virus (genotype 1). A positive fluorescent antibody test confirmed that it was infected with a lyssavirus, and PCR and genomic sequencing identified the virus as an EBLV-2a. Phylogenetic comparisons with all the published sequences from genotype 6 showed that it was closely related to the previous isolate of EBLV-2 in the UK and suggested links to isolates from bats in The Netherlands. The isolation of EBLV-2 from a bat found on the west coast of England provides evidence that this virus may be present within the UK Daubenton's bat population at a low prevalence level.  相似文献   
96.
The pregnancy rates obtained after the transfer of cryopreserved in vitro‐produced (IVP) embryos are usually low and/or inconsistent. The objective of this study was to evaluate the pregnancy rates of Holstein, Gyr and Holstein × Gyr cattle after the transfer of vitrified IVP embryos produced with X‐sorted sperm. Seventy‐two Gyr and 703 Holstein females were subjected to ovum pickup (OPU) sessions, followed by in vitro embryo production using semen from sires of the same breeds. Embryos (1636 Holstein, 241 Gyr and 1515 Holstein × Gyr) were exposed to forskolin for 48 h prior to vitrification. The pregnancy rate achieved with Gyr dam and sire was 46.1%, which was similar (p = 0.11) to that of Holstein dam and Gyr sire (40.3%). Crossing Gyr dams with Holstein sires resulted in a pregnancy rate of 38.9% and did not differ (p = 0.58) from the pregnancy rate obtained with the cross between Holstein dams and Gyr sires. The rate obtained with Holstein dam and sire was 32.5%. The average pregnancy rate was 36.6%, and no difference was found in the proportion of female foetuses (88.8%, in average) among breeds (p > 0.05). In conclusion, transfer of cryopreserved X‐sorted embryos represents an interesting choice for dairy cattle. Despite the small differences between pregnancy rates, we highlight the efficiency of this strategy for all of the racial groups studied.  相似文献   
97.
GENERALISED GLYCOGENOSIS IN BRAHMAN CATTLE   总被引:4,自引:0,他引:4  
Generalised glycogenosis was diagnosed in Brahman cattle on 4 Queensland properties on the basis of clinical observations and pathological and biochemical findings. The disease presented as a problem of ill-thrift and poor growth rate in calves which eventually showed nervous signs. Histologically there was vacuolation in the cells of the central nervous system, heart and muscular tissues. Biochemical assay of liver and blood mononuclear cells demonstrated a deficiency of alpha-glucosidase. Parents of affected calves had approximately half the alpha-glucosidase activity of that found in normal cattle.  相似文献   
98.
Thirty-four newborn polled Hereford and polled Hereford cross calves affected with a condition previously described as neuraxial oedema and six normal calves were examined. None of the affected calves were seen to stand after birth and when first examined the calves were in lateral recumbency, with extension and crossing of the hindlimbs. All the affected calves were bright and alert, could lift their heads and apparently could see and hear. When the calves were encouraged to stand spontaneous and stimulus-responsive myoclonic extensor spasms, with whole body rigidity, were consistently observed. Thirty-two of the affected calves had macroscopic lesions in the coxae. No significant pathological or biochemical lesions were observed in the central nervous system of any of the calves. The water content of the cerebellum did not differ between normal and affected calves. As oedema of the central nervous system is not a feature of this condition it is more appropriate to describe it as inherited congenital myoclonus.  相似文献   
99.
100.
The proteins of wheat have a known propensity to aggregate into a variety of forms. We report here a novel nanostructure from wheat proteins, derived from a crude extract of high molecular weight glutenins. The structure was characterised by a significant thioflavin T (ThT) fluorescence and a fibrillar morphology by transmission electron microscopy (TEM). The ThT fluorescence and TEM data are suggestive of an amyloid structure, but the X-ray fibre diffraction data show a reflection pattern (4.02, 4.2–4.3, 4.6, 12.9, 19.3 and 38.7 Å) inconsistent with both the classic amyloid form and the previously described β-helix structure. The 4.6 Å reflection is consistent with that predicted for the amyloid inter-β-strand, and the absence of the inter-β-sheet distance at ≈10–11 Å is not unprecedented in amyloid-like structures. However, our observed X-ray reflection pattern has not been previously reported and suggests a novel wheat glutenin nanostructure.  相似文献   
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