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71.
Studies were conducted into effects of Rift Valley fever virus on oestrous and vaginal cytology in non-pregnant ewes. 6 pregnant and 8 non-pregnant local Barki ewes were subcutaneously inoculated with different doses of virus isolated from Sharkia Province. Observed were irregularities in the oestrous cycle (20-28 days inoculation) and anoestrum. The anoestrum smears included large non-cornified epithelial cells with large well stains centrally located nuclei together with a large number of bacteria. Abortion and retention of placenta occurred in pregnant ewes with prolonged puerperal heat up to 70 days. Inoculation of virus was followed by thermal response. Re-isolation of virus in BHK cells was possible from aborted foetuses and placenta.  相似文献   
72.

Context

Conflict over land use is endemic to natural resource management given the limited availability of resources and multiple stakeholders’ interests, but there has been limited research to examine conflict from an integrative social-ecological perspective.

Objectives

We sought to determine how the potential for land use conflict—a social construct—was related (or not) to ecological systems of landscapes.

Methods

Using participatory mapping data from a regional case study in Australia, we identified the potential for land use conflict using a model that combines spatially-explicit place values with preferences for specific land uses related to development and conservation. Multiple proxies of biodiversity were used to evaluate the landscape’s ecological systems at ecosystems and species levels. Range maps were used to identify areas of high species diversity value using the conservation planning software Zonation.

Results

We spatially intersected conflict areas with landscape attributes and found the potential for conflict over conservation to be higher in coastal areas than inland areas, more likely to be located in areas with moderate vegetation cover, more concentrated in ecosystems classified as ‘No Concern’ with moderate to high native vegetation. Potential conflict over conservation was disproportionately higher in areas with higher species diversity derived from conservation modelling.

Conclusions

The social-ecological associations in conflict analysis can inform impact assessment of land use plans on biodiversity, assist development of effective approaches to reconcile conservation and other land uses, support conservation planning by identifying priorities for conflict negotiation and understanding underlying factors for conflict.
  相似文献   
73.
Chicory (Cichorium spp.) is a valuable vegetable crop worldwide for its edible leaves and for the production of coffee substitutes from roots. Agrobacterium rhizogenes-mediated genetic transformation of two species of chicory (C. intybus and C. endivia) was investigated using Agrobacterium strain K599 harbouring p35SGFPGUS+ plasmid and two types of explants: leave and leaf stalks. This Agrobacterium strain proved to be competent in the transformation with transformation rate about (23.1%) in leaf explants of C. intybus. However, the transformation rate with C. endivia was much lower (3.6%). Moreover, the hairy roots appeared from different infection sites of the leaf explants. Several hairy roots of the two species were acquired, out of them 11 clones (C. intybus) and two clones (C. endivia) were selected due to their fast-growing character. Growth of hairy roots was determined on the basis of total root biomass accumulation. It was found that the liquid MS-basal medium seems to be the most suitable for biomass production. PCR analysis revealed foreign DNA integration in the selected transgenic hairy root clones. Notable, the transgenic hairy roots exhibited substantially higher growth rates and accumulated higher amount of inulin than non transgenic roots (WT). Also, the total phenolic compounds were determined.  相似文献   
74.
Preservation of elite key lime (Citrus aurantifolia) genotypes using efficient micropropagation and regeneration protocols is very important for new breeding programmes. The objective of the present study was to develop an efficient protocol for micropropagation and maintenance of elite genotypes of key lime based on slow growth and starvation strategy. To do this, regenerated shoots were starved, and the growth was compromised via avoiding subcultures for 4, 8, 12 and 24 months. The numbers of responsive explants and adventitious shoots per each explant were evaluated in the presence of benzylaminopurine (BAP). The results showed that the 12- and 24-month starved explants treated with 1 mg/l BAP were able to produce four times more shoots than the control. In addition, the influences of horizontal or vertical layering explants over medium were evaluated. The results indicated that all horizontally layered explants significantly produced 25% adventitious shoots more than vertical explants, most likely owing to more contact with the surface medium. Finally, it could be concluded that application of slow growth, starvation strategy and also horizontally layering of the explants could efficiently enhance micropropagation and maintenance of threatened elite key lime genotypes with a low cost.  相似文献   
75.
Tropical Animal Health and Production - Burkholderia mallei, the etiologic agent of the disease known as glanders. Clinical and bacteriological diagnosis of glanders is difficult in the early...  相似文献   
76.
  1. An in vitro and in vivo study was conducted to evaluate the fermentability of isolated galactoglucomannan oligosaccharides (GGMs) and the influence of their feeding on shedding and colonisation of Salmonella typhimurium, growth performance and intestinal morphology in broiler chicks.

  2. The in vitro data demonstrated that three probiotic lactic acid bacteria namely Lactobacillus casei, L. plantarum and Enterococcus faecium were able to ferment the extracted oligosaccharides and other tested sugars on a basal de Man Rogosa Sharpe media free from carbohydrate.

  3. For the in vivo experiment, 144 one-d-old male Ross 308 broiler chicks were divided into 6 experimental treatments (with 4 replicates) including two positive and negative controls which received a basal maize-soybean diet without any additives, supplementation of three levels of isolated GGMs (0.1%, 0.2% and 0.3%) and a commercial mannanoligosaccharide (MOS) at 0.2% to the basal diet. All birds except those in the negative control group were challenged orally with 1 × 108 cfu of S. typhimurium at 3-d post-hatch.

  4. The results revealed that challenge with S. typhimurium resulted in a significant reduction in body weight gain, feed intake, villus height, villus height to crypt depth ratio and villus surface area in all of infected chicks. Birds that were given GGMs or MOS showed better growth performance, increased villus height and villus surface area and decreased S. typhimurium colonisation than the positive control birds. GGM at 0.2% level was more effective than the other treatments in improving growth rate as well as gut health of broiler chicks.

  相似文献   
77.
High levels of guanidinoacetate acid (GAA) deteriorate growth response in broiler chickens. We propose using coenzyme Q10, an antioxidant, and taurine (TAU), a methyl donor, to cope with the situation when high level of GAA included in diet. GAA was supplemented at 0 (control), 0.75, 1.5 and 2.25 g/kg in isoenergetic and isonitrogenous diets and fed to broilers (Cobb 500) from 1 to 40 days post‐hatch. Three additional diets were prepared by adding CoQ10 (40 mg/kg), TAU (40 mg/kg) or their combination (both CoQ10 and TAU at 40 mg/kg) to the 2.25 g/kg GAA group. The experimental design used was a completely randomized design. While weight gain (p = 0.038) and feed conversion ratio (p = 0.024) improved when GAA added at 1.5 g/kg, higher supplementation (2.25 g/kg) deteriorated these responses. These responses, however, were significantly restored by using CoQ10, TAU or their combination. Abdominal fat deposition was significantly decreased when TAU added to broiler diets by virtue of upregulating peroxisome proliferator‐activated receptor alpha. Supplementing broiler diets with CoQ10 and TAU or their combination significantly decrease ascites mortality. In conclusion, CoQ10 and TAU have shown beneficial effects when high level of GAA included in broiler diets.  相似文献   
78.
The aim of the present study was to investigate the efficacy of early single‐dose probiotics administered from proximal or distal gastrointestinal tract on quails’ performance and small intestinal morphology. A total of 120 Japanese quail (Coturnix coturnix japonica) 1‐d‐old chicks were divided into the following experimental groups before being transferred to the raising room: (i) control (no probiotic administered); (ii) oral group (received probiotics via oesophageal gavage); and (iii) vent lip group (received probiotics directly into vent). Four replicates of 10 chicks per cage were considered for each treatment and birds were raised up to 35 days in the same conditions with ad libitum access to feed and water. A commercial probiotics (Protexin, Somerset, UK) used in this study contained 2 × 109 cfu/g of nine different micro‐organisms. On day 35, all birds were weighed and then three birds in every pen were killed via cervical dislocation. Two cm of mid‐point of duodenum and ileum were cut for histomorphology assays. Both probiotics‐treated groups had higher body weight and body weight gain than control (< .01). Ileum was longer in probiotics‐treated groups than in the control (< .01). Orally treated birds had the highest duodenum villus height and crypt depth (< .01). In the cloacally treated quails, ileum villus length was higher than the both other groups, and crypts’ depth was deeper than the control (< .01). The numbers of both types of goblet cells (acidic mucin producer and neutral mucin producer) were higher in the birds receiving probiotics than control birds (< .01). Although there were no statistical differences in performance values between the different ways of probiotics entrance into gut, some intestinal histomorphometric parameters were improved in ileum of the birds receiving probiotics through distal gut that is cloaca (< .01).  相似文献   
79.
The role of dietary lemon peel (LM) and/or Bacillus licheniformis (BL) on the growth, immunity, and resistance against Aeromonas hydrophila in common carp, Cyprinus carpio was investigated in this study. LM and BL were included in diets at 0% (T0), 108 CFU/g BL (T1), 1.5% LM and 108 CFU/g BL (T2), and 3% LM and 108 CFU/g BL (T3). Fish fed with T1, T2, or T3 had higher weight gain, specific growth rate, white blood cells count, and blood total protein with lower feed conversion ratio than T0 group (p < .05). The albumin increased significantly (p < .05) in fish fed both BL and LM (T3). The serum superoxide dismutase (SOD), catalase, lysozyme, and bactericidal activities were significantly increased in fish fed both BL and LM (T2 and T3), while serum glutathione peroxidase increased in fish fed BL (T2) (p < .05). Fish fed T1, T2, and T3 diets displayed higher SOD and lower malondialdehyde than fish fed T0 (p < .05). After the A. hydrophila challenge, the mortality rate was significantly lower in T1, T2, and T3 groups than the T0 group (p < .05). The obtained results revealed that LM and BL could be used to increase resistance against A. hydrophila infection in carp. However, further field studies should be performed to confirm the obtained results.  相似文献   
80.
The occurrence of pathogenic bacteria, Aeromonas hydrophila, in farm‐raised fish requires urgent attention. Continuous and indiscriminate use of antibiotics as growth promoters and disease control agents in aquaculture have been discouraged because of the risk of development of antibiotic‐resistant bacterial strains. There is steady interest in the use of botanicals, such as clove, Eugenia caryophyllata, buds extract (ECBE), as alternatives. Hence, the present study evaluated the effect of dietary ECBE supplementation on the growth performance, physiological, antioxidant, and immunity biomarkers of African catfish, Clarias gariepinus. Fish (11.7 ± 0.5 g) were fed diets containing 0.0 (control), 5.0, 10.0, or 15.0 g ECBE/kg diet up to apparent satiation twice daily for 12 weeks. After the feeding trial, fish from each treatment were challenged with A. hydrophila infection by intraperitoneal injection and kept under observation for 14 days to record any abnormal clinical signs and daily mortality. The results demonstrated that fish performance and feed intake were significantly enhanced with increasing ECBE levels, and its optimum level is 15 g/kg diet. Further, the dietary ECBE increased significantly the intestinal villi length/width and absorption area in a dose‐dependent manner. There are significant progressive increases in the values of red blood cells, hemoglobin, hematocrit, white blood cells, platelets, lymphocytes, and heterocytes, while monocytes, eosinophil, and basophils decreased significantly due to dietary ECBE in a dose‐dependent manner. Highest glucose, cholesterol, total protein, globulin, and albumin‐globulin ratios, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, and creatinine values were found in fish fed 15 g ECBE/kg diets, while lowest values were recorded in fish fed the control diet. Despite the high AST and ALT values, no visible lesions or damage were observed in the liver cells of fish fed ECBE‐enriched diets. In addition, the inclusion of ECBE in fish diets enhanced the antioxidant and immunity capacity. Fish mortality after the bacterial challenge was higher in fish fed the control diet (82.3%) than those fed ECBE‐enriched diets. The lowest fish mortality was observed in fish fed the 15 ECBE/kg diet (4.7%) [Correction added on 16 November 2018: this section has been revised for clarity.].  相似文献   
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