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81.
Butyrate modulates intestinal epithelial cell structure and function. Three hundred and sixty Lohmann LSL‐Classic layer cockerels were used to investigate the effect of butyrate on heat stress‐induced intestinal injury and intestinal integrity. The experiment was conducted from day 85 to 105 of age. The birds were divided randomly into three treatments: control, heat stress (HS), and heat stress provided with butyrate (HSB) at a level of 0.35 g/kg of diet. The control was reared at 21 ± 1 °C throughout the experiment. The HS and HSB treatments were exposed to a cyclic HS (35 ± 1 °C from 09:00 to 13:00 and 21 ± 1 °C from 13:00 to 09:00). Intestinal and mucosal weights, villus height, villus surface area (VSA), absorptive epithelial cell area and intestinal beneficial bacteria were lower in the HS treatment than in the other two treatments (p < 0.05). Heat‐stressed cockerels exhibited the highest (p < 0.05) villi injury scores and serum endotoxin levels compared with the other treatments. Dietary inclusion of butyrate increased (p < 0.05) intestinal and mucosal weights, villus height, VSA, absorptive epithelial cell area and intestinal beneficial bacteria counts and reduced (p < 0.05) HS‐induced injury in intestinal epithelia as well as intestinal permeability to endotoxin. In conclusion, dietary butyrate exerted protective effects against intestinal damage induced by HS and improved intestinal health and integrity.  相似文献   
82.
Semiarid soils are subjected to wetting and drying cycles which influence sorption and desorption of applied phosphorus fertilizer. Phosphorus desorption was determined in soils from toposequences of two soil groups (Ferralsol and Luvisol) from a semiarid area, subjected to wetting and drying cycles. Samples from surface and subsurface horizons of upslope, midslope, and downslope positions were incubated for 4 months with phosphorus doses corresponding to 0, 5, 10, 25, 50, 75, and 100% of the maximum adsorption capacity, under constant moisture (80% water retention capacity) or 12 cycles of wetting and drying. Phosphorus desorption was lower in the Ferralsol than in the Luvisol, and lower in the subsurface than in the surface horizons, probably due to greater clay, Fe, and Al oxides contents, but they were similar among slope positions, of same mineralogy. Desorption tended to be greater in samples submitted to wetting and drying cycles but differences were small. P recovery reached 40–50% in the Luvisol, and 30–40% in the Ferralsol. The relatively low P retention capacity suggests a high residual effect of the P applied. Therefore, in relation to P losses, water retention techniques are less important than those that prevent soil erosion.  相似文献   
83.
Tree height-diameter allometry, the link between tree height and trunk diameter, reflects the evolutionary response of a particular species’ allocation patterns to above and belowground resources. As a result, it differs among and within species due to both local adaptation and phenotypic plasticity. These phenotypic variations in tree height-diameter allometry determine tree productivity, resistance and resilience to climate variation and, ultimately, the success of plant material used in restoration projects. We tested the effect of climate change and population origin on the phenotypic variation of tree allometry in four pine species at an early stage of development (ca. 11 years old) based upon data originated from multi-site provenance tests and planted along a wide climatic range in south-western Europe. For a representative sample of populations from each species, we used already-developed species-specific height-diameter allometric models to assess changes in allometry between present and future climatic conditions. We found that Pinus halepensis and Pinus pinaster were the most plastic species, while Pinus sylvestris and Pinus nigra showed negligible plastic responses. In addition, our models stressed that pine tree height-diameter allometry will change and phenotypic variation could increase, except in P. sylvestris, under future environmental conditions. For some of the species, this might allow the selection of phenotypes better suited to novel climatic conditions. These foreseeable changes in tree height-diameter allometry (among and within-species) could entail eco-evolutionary effects on the early forest plantation dynamics. Therefore, restoration and reforestation plans should consider these effects, as they may interfere with production and/or environmental goals.  相似文献   
84.
Dromedary camels complaining from conception failure or abortion were investigated and their herders interviewed in Al Ahsa province, Kingdom of Saudi Arabia (KSA) during 2013 and 2015. The most important reproductive disorder according to the responders is uterine infection (60.2%) followed by obesity (22.3%) then physiological conditions (hormonal disturbances; 7.8%), adhesions (3.9%) and repeat breeders (2.9%). Of the camel herders, 78.6% reported previous occurrence of abortion in their herds and 46% reported abortion cases in the last season (2015/2016), while 21.4% reported no history of abortion. Most of the responders (97.1%) do not call a veterinarian for cases of abortion in their herds and 53.4% do not discard aborted materials. The majority of the herders (76.7%) deny that handling aborted materials or touching vaginal fluids can result in human infection, or replied they do not know. Uterine swab samples were collected and tested by PCR for seven potential pathogens and sera tested for antibodies against bovine viral diarrhea virus (BVDV) and Brucella. Five pathogens were identified in infected uterine samples, namely Coxiella burnetii (36%), Campylobacter spp. (27%), Brucella spp. (17%), Salmonella spp. (13%), and Chlamydia spp. (7%). Sero-prevalence of Brucella and BVDV was 8.2 and 29.1% in overall sera, respectively, and varies with regard to the region. The findings of the present study demonstrate that reproductive disorders dominated by uterine infections and abortions are widespread in dromedary camels in KSA.  相似文献   
85.
Tropical Animal Health and Production - Porcine circovirus type 2 (PCV2) has been identified in pig population in Brazil since 2000, but scarce studies involving wild boars with PCV2 infection are...  相似文献   
86.
The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods.  相似文献   
87.
88.
  • ? Interpopulation variation in key functional traits of Pinus pinaster Ait. is well recognized. However, the relative importance of drought tolerance to explain this regional variation in the species remains elusive.
  • ? Here, we raise the question whether water availability constitutes a likely driver of regional variation in biomass allocation, growth and morphological traits of ten populations that cover the distribution range of P. pinaster. We carried out an experiment where seedlings of five families per population were submitted to two contrasting watering treatments.
  • ? The effects of water availability and population were significant for relative diameter and height growth rate, biomass allocation and number of lateral stems and dwarf shoots. Total dry mass significantly differed between watering treatments but it did not among populations. Populations could be clustered into four main groups. Root mass fraction explained most of the variation and significantly correlated to altitude but not to aridity.
  • ? The geographical pattern of genetic variation found in morphology and biomass allocation did not translate into population differences in drought tolerance or phenotypic plasticity to water availability, indicating that water availability is not a likely driver of the regional variation observed in the studied traits of P. pinaster at the seedling stage.
  •   相似文献   
    89.
    90.
    Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry, and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion, the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance in the diagnosis of atrophy and pathogenic conditions of these glands.  相似文献   
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