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21.
A field experiment was carried out to evaluate the effect of two whole-crop rice (Oryza sativa L.) cultivars, TULT and Takanari, on methane (CH4) emission in a paddy field fertilized with biogas slurry (BS) at rates of 0 (NF), 100 (BS100) and 300 (BS300) kg nitrogen (N) ha?1, in comparison with chemical fertilizer CF100 (100 kg N ha?1). Takanari produced significantly higher biomass (< 0.001) than TULT and showed significantly (< 0.01) lower CH4 emission than TULT. BS applications caused higher CH4 emission (52 ± 27 and 80 ± 19 g m?2 in BS100 and BS300, respectively) than did CF100 (42 ± 18 g m?2) and NF (28 ± 10 g m?2) in TULT. In contrast, there was no significant difference in CH4 emission in Takanari among the treatments (26 ± 2, 26 ± 2, 32 ± 4, 29 ± 8 g m?2 in NF, CF100, BS100 and BS300, respectively). Methane oxidizing bacteria (MOB) showed significantly (< 0.05) higher populations in Takanari than in TULT at harvest, which might be due to the higher root biomass (10.3 ± 2.2 g hill?1) in Takanari than in TULT (8.9 ± 1.8 g hill?1). MOB was significantly correlated with tiller number (R2 = 0.176*) and plant biomass (R2 = 0.242*). BS application showed higher copper (Cu) uptake in Takanari while it was not high in TULT. In contrast, it showed no difference in zinc (Zn) uptake in both varieties. Uptake of Cu was not different between the two varieties, while uptake of Zn in the grain was higher in TULT than in Takanari. The present study suggests that CH4 emission deriving from BS application in paddy field can be mitigated by selecting an appropriate cultivar, like Takanari. However, care should be taken for heavy metal uptake in selecting cultivars.  相似文献   
22.
The aim of this study was to develop a radiographic standard for the assessment of pulmonary fluid clearance and lung aeration in newborn calves. Caesarean‐delivered mature calves (= 9) underwent lung assessment by thoracic radiography as well as arterial and venous blood gas analysis within the first 30 min, 1, 2, 3, 6, 12 and 24 hr after birth. The results indicated that newborn calves delivered by elective Caesarean section suffered from a physiological combined respiratory and metabolic acidosis with the dominance of respiratory acidosis, and an improvement in these conditions was recorded within 24 hr after birth. Concerning the radiographic results, clear lung fields, improvement in lung expansion, air content of the lung and absence of lung opacification occurred within 24 hr of birth. Furthermore, the ventral lung quadrant showed an improvement in radiographic opacification and lung expansion earlier than the dorsal lung regions. The findings of this study support the potential role of thoracic radiography in the assessment of pulmonary fluid clearance and lung aeration in newborn calves.  相似文献   
23.
Tropical Animal Health and Production - The central dry zone of Myanmar is the area with the highest density of small-scale livestock farmers under harsh environmental condition. In this study, we...  相似文献   
24.
We have examined the effects of different types of slurry on CH4 and N2O emissions, Zn and Cu contents of rice, and nitrate content of the drainage water. The experiment included four treatments: (1) anaerobically digested cattle slurry (ADCS), (2) ADCS filtered to remove the coarse organic matter fraction, (3) anaerobically digested pig slurry (ADPS), and (4) chemical fertilizer (CF). The application rate was 30?g?NH4?CN?m?2. Different amounts of C were incorporated with fertilization: 725?g?C?m?2 in ADCS, 352?g?m?2 in filtered ADCS, and 75?g?m?2 in ADPS. The average CH4 emissions during a growing period were 304, 359, 452, and 579?mg?m?2?day?1 in the CF, ADPS, filtered ADCS, and ADCS treatments, respectively. The CH4 emission was significantly higher in ADCS than in CF and ADPS. Negligible N2O emissions were observed during the growing period. Comparable concentrations of Zn and Cu were observed in the rice grain among the treatments. In contrast, their concentrations in the stems and leaves were significantly higher in ADPS than in CF treated rice, although the values were lower than the upper limit of feed additives. Nitrate concentrations in the drainage water were consistently low (0.5?mg?N?L?1). The present study suggested that ADPS, containing a lower amount of C than ADCS, might be an organic fertilizer in paddy field with comparable environmental impacts to chemical fertilizers (CF), but long-term field studies are needed to better understand the effects of these organic fertilizers.  相似文献   
25.
将 36头试验猪分成 4组 :β 肾上腺素能激动剂处理组即克伦特罗处理组 (1kg饲料添加克伦特罗 3mg ,连续 2 8d)、生长激素处理组 (按 1kg体重每日注射 0 1mg生长激素 ,连续 2 1d)、克伦特罗和生长激素混合处理组及空白对照。试验结束后 ,测定猪的胴体组成 ,结果表明 :克伦特罗处理组和生长激素处理组的日增重分别比对照组提高 17%和 19% ,而混合处理组的日增重则下降 38% ,饲料摄入量下降 39% ;克伦特罗处理组背最长肌面积增加 19% ,背膘厚下降 2 3% ,与之相比 ,生长激素能加强猪的基础合成代谢 ,因而胴体成分没有明显改变 ;克伦特罗和生长激素混合处理组的活重减轻 ,胴体和内脏的比例下降 ,胴体明显瘦于对照组 ,但最长肌面积相等。结果还表明 β 肾上腺素能激动剂和生长激素对猪的饲料摄入量和胴体组成有互作效应 ,有关机理还需进一步研究。  相似文献   
26.
Paddy and Water Environment - In Myanmar’s Ayeyarwady Delta, mangrove forests were widely converted to paddy fields, then abandoned. However, the mangrove ecosystems often fail to recover. To...  相似文献   
27.
CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival. However, measuring the effectiveness and impacts of these trade regulations for commercially exploited aquatic species remains challenging. This study highlights observed or documented changes in elasmobranch fisheries in eight Southeast Asian countries before and after the listing of sharks and rays in CITES’ Appendix II, and the influence of CITES across five pillars or sectors of a “fishery assessment framework” developed especially for this purpose. Fisheries experts reported change was most common in the “governance” (e.g., policy, regulation and compliance) and “fisher(y)” sectors (e.g., structure and effort) of the assessment framework. The smallest change was recorded in “markets” (e.g., structures and prices) and “sociocultural” sectors (e.g., consumption, livelihoods and community awareness). Overall, the study demonstrates a measurable, albeit small, mostly positive influence of CITES in five of eight countries, while noting predominantly negative influences across two, and ongoing challenges for all in maintaining legal trade of these CITES‐listed species. The study concludes by offering guidance on future needs: most notably, more effort for long‐term collection of fundamental fisher‐, stock‐ and market‐related data to inform adaptive management and facilitation of legal trade where it is shown to be sustainable. Furthermore, as many of the shark and ray species under CITES provisions are transboundary stocks, increased support for communication and cooperation among regional fishery stakeholders is an ongoing need.  相似文献   
28.
29.
Fifty‐seven genital tracts of regularly slaughtered culled Piedmontese cows, aged 7.4 ± 4.3 years (mean ± SD), range: 2.6–15.6 years, were grossly and microscopically examined. DNA extracted from oviducts was subjected to PCR to evaluate the presence of Chlamydia spp. The 15 PCR‐positive oviducts were subjected to Sanger sequencing and showed the presence of Chamydia abortus, with an identity range between 99 and 100%. Nine of the PCR‐positive samples belonged to the 24 animals with a normal macroscopic appearance of the whole genital tract (percentage of positive oviducts in normal genital tracts 9/24 = 37.5%), while six belonged to the 33 genital tracts with lesions in one or more organs (percentage of positive oviducts in pathological genital tracts 6/33 = 18.1%); of these, a single animal had salpingitis. The detection of C. abortus in bovine oviducts is of particular interest because it has never been previously investigated or reported.  相似文献   
30.
Tilapia lake virus (TiLV) is a highly contagious pathogen that has detrimental effects on tilapia farming. This virus was discovered in 2014 and has received tremendous global attention from the aquaculture sector due to its association with high fish mortalities and its strong economic impact on the tilapia aquaculture industry. Currently, TiLV has been reported in 16 countries, and this number is continuing to rise due to improved diagnostic assays and surveillance activities around the world. In this review, we summarize the up-to-date knowledge of TiLV with regard to TiLV host species, the clinical signs of a TiLV infection, the affected tissues, pathogenesis and potential disease risk factors. We also describe the reported information concerning the virus itself: its morphology, genetic make-up and transmission pathways. We review the current methods for virus detection and potential control measures. We close the review of the TiLV story so far, by offering a commentary on the major TiLV research gaps, why these are delaying future TiLV research and why the TiLV field needs to come together and proceed as a more collaborative scientific community if there is any hope limiting the impact of this serious virus.  相似文献   
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