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101.
102.
This study aims to characterize the reproductive patterns in Asinina de Miranda jennies during the non‐breeding season. Reproductive activity was surveyed in 12 females, aged between 3 and 18 years old, using ultrasound and teasing with a jack. The animals were monitored from September to April, six in each consecutive year. Of these 12 females, nine showed disruption to the normal pattern of ovarian activity during the non‐breeding season. Loss of normal cyclicity included anoestrus (41.7%), silent ovulatory oestrus (25%), and persistence of corpus luteum (8.3%). Only three females maintained a regular cyclic pattern with oestrous behaviour during the non‐breeding season. Anoestrus began in early November and lasted for an average of 147 ± 28 days (113–191 days), ending near to the spring equinox. Onset of silent oestrous cycles began more erratically, between October and February. In both groups the first behavioural ovulation of the year occurred around the time of the spring equinox. Disrupted reproductive activity was preceded by a shorter oestrous cycle only in females entering anoestrus. The mean follicle size in the first ovulation of the year was larger than in the reproductive season (44.7 ± 2.45 mm vs 39.2 ± 3.60 mm) in anoestrous jennies with protracted oestrus. Though age and body condition score (BCS) were associated, changes in BCS below a threshold of four points (for anoestrus) and five points (for silent oestrus) contributed greatly to disruption of reproductive cycles. BCS in females with regular oestrous cycles during the winter season remained unchanged or exceeded five points prior to the winter solstice.  相似文献   
103.
In this study, the effect of edible coarse/nanoemulsions of alginate as coating containing Zataria multiflora Boiss essential oil (ZEO) on the microbial quality of fish fillets was investigated at three concentrations (i.e. 0.25%, 0.5% and 1% [w/v]) in 16 days of storage at 4°C. Moreover, a comparison was made between the fabricated coarse emulsion and nanoemulsion coatings by particle size and polydispersity index analyses. Sample analysis was performed with regard to total viable count (TVC), total psychrophilic count (TPC), hydrogen sulphide‐producing bacteria count (HSC) and Enterobacteriaceae count (ENC) on days 0, 4, 8, 12 and 16. According to the findings, all the samples showed increased microbial counts during the storage periods. The highest reduction rates of TVC (about 2 log CFU/g), TPC (about 1 log CFU/g), HSC (about 1.5 log CFU/g) and ENC (about 3 log CFU/g) were observed in the nanoemulsion of alginate containing 1% w/v ZEO (NE 1%) samples, compared with alginate and control samples. The microbial growth was significantly inhibited in all treatments, compared with that in the control (p < .05). Accordingly, it can be concluded that nanoemulsion coating was more effective than coarse emulsion to prolong the durability of fish fillets and revealed a faster and greater inhibition of microbial flora, compared with coarse emulsions during the storage time.  相似文献   
104.
1. This experiment was conducted to evaluate the effects of replacing dietary cottonseed meal (CSM) or fermented cottonseed meal (FCSM) for soya bean meal (SBM) on growth performance, carcass characteristics, gastrointestinal microbial populations, and intestinal morphology of broiler chickens.

2. CSM was fermented with Bacillus subtilis, Aspergillus niger and A. oryzae for 7 d. A total of 300 one-d-old male Ross 308 broiler chickens were used in a 42-d experiment in which the birds were randomly allotted to one of 5 dietary treatments (containing 0%, 10% and 20% CSM or FCSM) in a completely randomised design. Birds were reared on litter floor and had free access to feed and water during the experiment.

3. Results indicated that the fermentation process significantly reduced crude fibre and free gossypol, while it increased crude protein content and lactic acid bacteria (LAB) count in CSM.

4. The use of FCSM instead of CSM significantly improved growth performance of broilers. The abdominal fat yield in treatments containing FCSM was significantly lower than in the other treatments. The increase in the population of LAB in the crop and decrease in the population of coliforms in the ileum of birds fed on diets containing FCSM were more significant than in other birds. Villi in the duodenum and jejunum of the birds fed on diets containing FCSM were significantly higher than for the other experimental groups.

5. The positive effects of diets containing FCSM on growth performance and intestinal health of broiler chickens showed that this processed source of protein can serve as an appropriate alternative for SBM in diets for broiler chickens.  相似文献   

105.
106.
Growing soybeans in different row-spacings introduces competition. Competition begins when the immediate supply of a single necessary factor falls below the combined demands of all plants. This paper reviews the main competition factors of genotypes, light, water, nutrients and weed in responses to row spacings for the past four decades. It demonstrated that responses of soybean genotypes to row width differ among cultivars, which depend on seasonal rainfall and irrigation. Determinate types produce more yield in narrow-rows, and cultivars with lodging resistance should be adopted in narrow-spacings, but indeterminate soybean should also be used to optimize yields in certain system. Narrow-compared with wide-row soybean (Glycine max) cultivation increases light interception (L]) and dominant components for the increase come from LA], light extinction coefficients and branch types. Water use efficiency (WUE) and evapotranspiration are not influenced by row spacing, but seed yield could be increased if irrigationis applied. Nutrient uptake is significantly affected by row spacing, seed yields and uptake of N, P, K in plants increases with decreasing row spacing, and the effects depend on the fertilizer levels. Other factors rather than row spacing affect nitrogen fixation. Weed density, peak time and periodicity of weed emergence are not affected by row spacing, but better complementary weed control by the herbicides at the used doses can be obtained in narrow spacing due to the reduoed weed number and dry weight. More researches are required to investigate the physiological responses, nutrient and water uptake and translocation, light utilization at different layers of canopy and soil environment changes in different row-spacings.  相似文献   
107.
Artificial keratoprostheses are indispensable for visual rehabilitation in patients with end-stage corneal blindness. This study aimed to assess the biocompatibility of polyethylene terephthalate nanofibrous mats and its potential as a novel synthetic keratoprosthesis skirt material for corneal tissue engineering. Nanofibrous mats were prepared by an electrospinning method and were first treated with the CO2 plasma to yield carboxylic groups on the surface; finally, the modified PET mat was cross linked with collagen using water-soluble carbodiimide as a coupling agent. The samples were evaluated by ATR-FTIR, scanning electron microscope (SEM), contact angle, and cell culture. The cross-linking of collagen on PET surface was confirmed by ATR-FTIR spectroscopy and SEM images The 79° difference was obtained in the contact angle analysis, obtained for the collagen-cross-linked nanofibrous mat than the non-modified nanofibrous mat. Cellular investigation showed limbal epithelial progenitor cells (LEPCs) has been better adhesion, cell growth, and proliferation of collagen-crosslinked nanofibrous samples than other samples. The bioavailability of PET fibers with covalently attached collagen was found to be identical to that of PET fibers with covalent attachment is a suitable method for enhancing the biocompatibility of scaffolds special as a good skirt in keratoprosthesis designs.  相似文献   
108.
Summary Salvia columbariae is a herbaceous annual species which has potential for domestication as a new source of industrial oil. Isozyme markers provide a mean by which this process may be facilitated. Isozyme survey of field grown Salvia columbariae plants showed variation for malate dehydrogenase (MDH), phosphoglucose isomerase (PGI), and phosphogllucomutase (PGM). Selfed seed was obtained from the field and was grown in the greenhouse for segregation analyses. Electrophoretic results indicated that MDH was variable at zone 1, showing presence or absence of a band. The observed segregation ratio was not significantly different from expected ratio for Pgi-4 and Pgm-3 isozymes, indicating monogenic control of the two loci. Pgi-4 locus was heterozygous for a null allele. Cross dimerization between the allozyme Pgi-3 and Pgi-4 loci resulted in an intergenic band for this isozyme system.Abbreviations ACO aconitase - ADH alcohol dehydrogenase - DTT-DL dithiothreitol - FDH formate dehydrogenase - GOT glutamate-oxalacetate transaminase - IDH isocitric dehydrogenase - MDH malate dehydrogenase - MNR menadione reductase - 6PGD 6-phosphogluconate dehydrogenase - PGI phosphoglucose isomerase - PGM phosphoglucomutase - PVP-40 polyvinylpyrrolidone - SKDH shikimate dehydrogenase - TPI triosephosphate isomerase  相似文献   
109.
Previous studies have suggested that melting processes are responsible for the trace element variability observed in olivine-hosted basaltic melt inclusions. Melt inclusions from three individual lava samples (two from Mangaia, Cook Islands, and one from Tahaa, Society Islands) have heterogeneous Pb isotopic compositions, even though the erupted lavas are isotopically homogeneous. The range of Pb isotopic compositions from individual melt inclusions spans 50 percent of the worldwide range observed for ocean island basalts. The melt inclusion data can be explained by two-component mixing for each island. Our data imply that magmas with different isotopic compositions existed in the volcanic plumbing system before or during melt aggregation.  相似文献   
110.
Soil compaction generally reduces crop performance because of degraded soil physical and biological properties, and possibly inappropriate soil nutritional status. The effects of varying compaction, and phosphorus (P) and zinc (Zn) supplies on the growth of Berseem or Egyptian clover (Trifolium alexandrimum), and accumulation of P and Zn in shoots and roots were investigated in a pot experiment using a surface layer of a Typic Torrifluvent (USDA), Calcaric Fluvisols (FAO) soil. Plants were treated with three soil compaction levels, three rates of P and three rates of Zn in a factorial combination. Phosphorus accumulation in shoots did not change up to bulk densities of 1.65 Mg m−3 and declined at bulk density of 1.80 Mg m−3. Increasing the levels of Zn and P resulted in a significant increase in shoot dry mass (from 0.3 to 0.8 g pot−1), and root length (from 11.4 to 32.5 m pot−1). Shoot and root growth were reduced by soil compaction particularly at low P and Zn application rates. Shoot dry mass was reduced from 0.8 to 0.3 g pot−1, and root length from 43 to 5 m pot−1 at bulk densities of 1.4 and 1.8 Mg m−3, respectively. However, the accumulation of P (from 0.06 to 0.15 g kg−1) and Zn per unit length of roots (from 0.8 to 1.8 μg pot−1) increased as soil compaction increased. As the Zn supply increased, Zn accumulation per unit length of roots, and total Zn accumulation increased. Severe compaction reduced P and Zn accumulation in shoots and also decreased shoot dry mass, and root length compared to lower soil compaction levels. The present study suggests that Zn and P supply can moderate the adverse effect of soil compaction on clover performance.  相似文献   
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