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41.
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Dietary intake of certain carotenoids has been associated with a reduced risk of disease. Kale (Brassica oleracea L. Acephala Group) has the highest levels of carotenoids lutein and beta-carotene, and is an excellent source of minerals among the green leafy vegetable crops. However, Brassica vegetables contain glucosinolate (GS) and S-methylcysteine sulfoxide (MCSO). While these sulfur compounds have medicinal value, they are also responsible for the bitter, acrid flavors that are often regarded as objectionable by consumers. Therefore, the objectives of this study were to investigate the influence of increased S fertility levels on (1) elemental accumulation, (2) GS and MCSO production, and (3) the accumulation patterns of carotenoid pigments in the leaves of three kale cultivars. Winterbor, Redbor, and Toscano kale were greenhouse-grown using nutrient solution culture with S treatment concentrations of 4, 8, 16, 32, and 64 mg of S/L. Decreasing S fertility decreased S leaf content, but increased the levels of Mg and Ca accumulation, two important minerals for human health. Levels of GS and MSCO decreased in response to a decreasing S level in nutrient solution. However, accumulation of lutein and beta-carotene was unaffected by S treatment. Lowering the S fertility in the production of kale should decrease the levels of negative flavors associated with high levels of GS and MCSO without affecting carotenoid pigment levels. Understanding the combined impact of fertility on flavor compounds and carotenoid pigments may help improve consumer acceptance of phytonutritionally enhanced vegetable crops.  相似文献   
43.
Summary Data from segregating generations of reciprocal crosses between an early and late emerging cultivar of C. baccatum var. pendulum suggested partial dominance for slow emergence at low temperatures, with additive and dominance gene action responsible for the expression of this trait.Received for publication 17 July 1979. Michigan Agricultural Experiment Station Journal Article No. 9081.  相似文献   
44.
Probiotics are widely available for use in animals but quality control of veterinary probiotics has been shown to be poor. The objective of this study was to evaluate the labels and bacterial contents of commercial probiotics marketed for use in animals. Twenty-five probiotics were purchased, labels were scrutinized, and bacterial contents were enumerated. Twenty-one (84%) products listed specific microorganisms. Expected bacterial numbers were listed for 15 (60%) products. One or more organisms were misspelled on the labels of 7/22 (32%) of products that listed specific organisms. Viable growth ranged from 0 to 2×10(9) colony forming units (CFU)/g. Only 4/15 (27%) products that had specific claims of viable organisms met or exceeded their label claim. Only 2 of these also had an acceptable label, which properly described the contents. Deficiencies in veterinary probiotic quality remain. Veterinarians and owners should scrutinize commercial probiotics and demand evidence of quality control and efficacy.  相似文献   
45.
Ten Apollo 11 specimnens were divided into 24 samtples. Sodillim contents of 8 diverse specimens clluster tightly abolit 0.3 percent. Plagioclase separated from sample 10044 contains aboltt 1.09 percent Na; barium is not enriched in the plagioclase separate. Contents of the rare earths are strikingly high, and relative abtmndances resemble those of calcium-rich achondrites or abyssal basalts but are depleted in Eu by factors of 2 to 3 and in La by about 20 percent. The plagioclase separate is enriched in Eu and pyroxenes (and opaqtte minerals are Eu-depleted. Fine fractions of 10044 are abotit 20 to 40 percent richer in most rare earths (50 percent for Eu) than coarse fractions, probably becaitse of the presence of small grains in which rare earths are mnarkedly concentrated. "Microgabbro" 10045 is imnpoverished, relative to the soil, in rare eartlhs and Hf. Ratios by mass of Zr to Hf are comlparatively low. Abttndances of Mn, Co, Fe, Sc and Cr stiggest systematic differences between igneous rocks on one hanid and breccias and "soil" on the other. Fromn the Co abuindances, no more than about 3 percent of the present "soil" can consist of chondritic mleteorite conitamination.  相似文献   
46.
  1. There is concern across the International Council for the Exploration of the Sea (ICES) region that a consideration of vulnerable components and the wider support mechanisms underpinning benthic marine ecosystems may be lacking from the process of marine protected area (MPA) designation, management and monitoring.
  2. In this study, MPAs across six European ecoregions were assessed from a benthic ecology perspective. The study included 102 MPAs, designated by 10 countries, and focused on three aspects regarding the role of the benthos in: (i) the designation of MPAs; (ii) the management measures used in MPAs; and (iii) the monitoring and assessment of MPAs.
  3. Qualitative entries to a questionnaire based on an existing framework (EU project ‘Monitoring Evaluation of Spatially Managed Areas’, (MESMA) were collected by 19 benthic experts of the ICES Benthic Ecology Working Group. A pedigree matrix was used to apply a numerical scale (score) to these entries.
  4. The results showed clear differences in scores between ecoregions and between criteria. The designation‐phase criteria generally achieved higher scores than the implementation‐phase criteria. Poor designation‐phase scores were generally reiterated in the implementation‐phase scores, such as scores for assessment and monitoring.
  5. Over 70% of the MPA case studies were found to consider the benthos to some extent during selection and designation; however, this was not followed up with appropriate management measures and good practice during the implementation phase.
  6. Poor spatial and temporal coverage of monitoring and ineffective indicators is unlikely to pick up changes caused by management measures in the MPA. There is concern that without adequate monitoring and adaptive management frameworks, the MPAs will be compromised. Also, there could be an increased likelihood that, with regard to the benthos, they will fail to meet their conservation objectives.
  7. This assessment was successful in highlighting issues related to the representation and protection of the benthos in MPAs and where changes need to be made, such as expanding the characterization and monitoring of benthic species or habitats of interest. These issues could be attributable to an ongoing process and/or an indication that some MPAs only have ‘paper protection’.
  相似文献   
47.
48.
A 21‐day experiment was conducted to investigate the effects of wheat particle size, insoluble fibre source and whole wheat (WW) inclusion on the gizzard musculature, intestinal architecture and nutrient utilisation of broiler chickens. The following seven treatments, all in mash form, were tested: control diet using finely ground wheat (Fine); control diet using medium‐ground wheat (Medium); control diet using coarsely ground wheat (Coarse); fine diet diluted with 10 g/kg lignocellulose (LC); fine diet diluted with 30 g/kg oat hulls (OH); fine diet diluted with 30 g/kg wood shavings (WS); and ground wheat in the fine diet replaced with 50 and 100 g/kg WW during the second (day 8–14) and third (day 15–21) weeks of the study respectively. Except for the LC diet, all treatments increased (p < 0.05) the thickness of the caudodorsal thick muscle of gizzard compared to the fine diet. The highest (p < 0.05) caudoventral thin and cranioventral thick muscle diameters in the gizzard walls were achieved with the OH and WS diets. Feeding OH, WS and WW diets improved (p < 0.05) starch digestibility compared with the fine diet, while medium, coarse and LC diets had no effect (p > 0.05). All diets containing fibre sources (LC, OH and WS) reduced (p < 0.05) the energy digestibility compared to the fine diet. Birds fed OH and WS diets gained the lowest (p < 0.05) weights. Feeding LC, OH, WS and WW diets increased (p < 0.05) the feed per gain compared with the fine diet. The current results suggest that there is a potential for coarse particles, insoluble fibre sources and WW feeding to improve the gizzard musculature and digestibility of some nutrients, with the effect being more pronounced with the inclusion of structural fibre sources.  相似文献   
49.
50.
With a 3-day duration of Stage I of composting, an initial nitrogen (N) content of about 1.4% of the dry matter resulted in a shorter time in Stage II and a 14-day earlier start to cropping than a 2.4% N content. In 6 weeks cropping from each compost, the yields of mushrooms were similar.Following 13 and 23 days in Stage I, initial N content had little or no effect on the duration of Stage II or on the start of cropping, but the yield of mushrooms was greater from composts with the higher N content. These results support the proposition that with increasing duration of composting a higher initial N content of the compost is acceptable, and probably desirable, for preparing a successful compost.A direct relation between duration of composting and losses of water and dry matter from the compost was confirmed.The occurrence of Coprinus spp. (ink caps) fruit bodies during mushroom cropping was not a good indication of subsequent yield of mushrooms.  相似文献   
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