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11.
BACKGROUND: In 2001 the UK Department of Health funded pilot community-based interventions to improve fruit and vegetable intakes in five economically deprived areas of England. The effectiveness of the programme and the use of a brief tool for evaluating community interventions are reported here. METHODS: Data on intakes of and beliefs about fruit and vegetables were collected by a short postal questionnaire (FACET--Five-a-day Community Evaluation Tool) simultaneously from 810 individuals living in the pilot communities and 270 individuals who were participating in an unrelated observational study (controls). Data were collected before and after a 12-month intervention period. Quantitative dietary data derived from 7-day food diaries available for control subjects were used to assess the ability of the FACET questionnaire to estimate fruit and vegetable intakes. RESULTS: Compared with controls, the intervention group significantly increased their knowledge of the 5-a-day optimum (P<0.01) and reported increased access to fruits and vegetables (P<0.001). Overall, the intervention had no demonstrable effect on total fruit and vegetable intakes as measured by FACET. However, smoking habit strongly predicted change in fruit and vegetable intakes (P<0.01) in the intervention group. Opposite trends were observed in the two groups, with 'smokers' and 'non-smokers' in the intervention and control groups respectively reducing their fruit and vegetable intakes. The FACET questionnaire agreed with food diary estimates of fruit and vegetable intakes in 56% of cases. CONCLUSIONS: Community-based interventions can produce important changes in knowledge of and access to fruit and vegetables. However, in this study change in fruit and vegetable intakes was strongly influenced by smoking habit. This bias needs to be considered in planning future intervention and evaluation programmes. The FACET questionnaire provides acceptable estimates of fruit and vegetable intakes which may be used for grading intake in large community-based projects.  相似文献   
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CASE DESCRIPTION: A cohort of 35,200, 13-week-old, female rainbow trout at a fish farm was evaluated because of a 2-week history of anorexia and lethargy and a mortality rate of approximately 100 fish/d. CLINICAL FINDINGS: Affected fish were lethargic and thin and had disequilibrium, bilateral exophthalmia, pale red gills and kidneys, red-tinged coelomic fluid, and pale brown livers. Some fish were differentially pigmented bilaterally. The presumptive diagnosis was bacterial or viral septicemia. The definitive diagnosis was rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum. TREATMENT AND OUTCOME: A strategy for controlling the outbreak based on reducing pathogen numbers in affected tanks and reducing pathogen spread among tanks was developed. The option of treating with antimicrobial-medicated feed was discussed with the farmer, but was declined. After changes were made, mortality rate declined quickly, with no more deaths within 10 days after the initial farm visit. CLINICAL RELEVANCE: Bacterial coldwater disease is the most common manifestation of infection with F psychrophilum in fingerling and adult rainbow trout. However, the organism can also cause rainbow trout fry syndrome. This condition should be included on a list of differential diagnoses for septicemia in hatchery-reared rainbow trout fry.  相似文献   
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Phytate (inositol-hexa-phosphate) has an important role in plants but it also may have anti-nutritional properties in animals and humans. While there is debate within the plant breeding and nutrition communities regarding an optimum level in grain, there appears to be little information at the molecular level for the genetics of this trait, and its association with important trace elements, in particular, Fe and Zn. In this preliminary study, quantitative trait loci (QTL) for grain phytates, Zn and Fe in glasshouse-grown rice lines from an IR64 × Azucena doubled haploid population were identified. Correlations between phytate and essential nutrients were also studied. Transgressive segregation was found for most traits. Phytate and total P concentrations had one QTL in common located on chromosome five with the (high concentration) allele contributed from Azucena. There were significant positive correlations between phytate and inorganic phosphorus (P), total P, Fe, Zn, Cu and Mn concentrations for both grain concentration and content. However, the QTLs of phytate were not located on the same chromosomal regions as those found for Fe, Zn and Mn, suggesting that they were genetically different and thus using molecular markers in breeding and selection would modify the phytate level without affecting grain micronutrient density.  相似文献   
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The bioavailability of Fe from 24 select genotypes of bean (Phaseolus vulgaris L.) seeds containing a range of concentrations of Fe, myo-inositol pentaphosphate plus phytic acid (IP5+IP6), and tannins was studied using a rat model. Bean accessions, selected from field trials for their variations in Fe, phytate, and tannin seed concentrations, were grown in a greenhouse in nutrient solutions radiolabeled with (59)Fe. Mature seeds were autoclaved and lyophilized. Test meals (containing 1 g of dried bean, 0.5 g of sucrose, and 1 g of basal Fe-deficient diet) were fed to marginally Fe-depleted weanling rats over a 3-h period; rats were radioassayed in a gamma-spectrometer immediately after feeding and daily thereafter for the next 10 d. Radioiron retention data were used to calculate percent Fe absorption (i.e., Fe bioavailability) from the meals. Seed Fe concentrations ranged from 52 to 157 microg g(-)(1) dry weight. There was a tendency to also select for higher Zn concentrations in the beans when selecting for high Fe concentrations. The Fe bioavailability to rats from test meals depended on the genotype and varied from 53% to 76% of the total Fe. Bean genotypes with higher seed Fe concentrations resulted in increased amounts of bioavailable Fe to rats. There was no significant correlation between the Fe concentration in different bean genotypes and Fe bioavailability to rats attributable to variations in IP5+IP6 or tannins, even though these antinutrients varied widely (i.e., from 19.6 to 29.2 micromol of IP5+IP6 g(-)(1) and from 0.35 to 2.65 mg of tannins g(-)(1)) in the test meals. Other unknown seed factors (i.e., antinutrients or promoter substances) may be contributing factors affecting Fe bioavailability from bean seeds.  相似文献   
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The addition of succinylsulfathiazole to highly purified diets containing all dietary factors known to be required by the rat, including pantothenic acid, results in the appearance of signs of severe pantothenic acid deficiency, including achromotrichia and porphyrin-caked whiskers. These changes are accompanied by a marked reduction in the pantothenic acid content of the liver, and are corrected by the inclusion in such diets of crystalline biotin and "folic acid" concentrates. The utilization of pantothenic acid by the rat appears to depend on the availability of biotin and "folic acid." Under normal conditions these are supplied by the diet and synthesized by intestinal bacteria. A hypothesis is offered in explanation of the chromotrichial actions of "folic acid," biotin and p-aminobenzoic acid.  相似文献   
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Soybean plants deprived of nickel accumulated toxic concentrations of urea (2.5 percent) in necrotic lesions on their leaflet tips. This occurred regardless of whether the plants were supplied with inorganic nitrogen or were dependent on nitrogen fixation. Nickel deprivation resulted in delayed nodulation and in a reduction of early growth. Addition of nickel (1 microgram per liter) to the nutrient media prevented urea accumulation, necrosis, and growth reductions. This evidence suggests that nickel is essential for soybeans and possibly for higher plants in general.  相似文献   
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