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11.
Vascular air embolism (VAE) is the entrainment of air from the operative field or other communication with the environment into the venous or arterial vasculature, producing systemic effects. The horse described in this report, after having been discovered to have dislodged the extension set from the jugular vein catheter, demonstrated clinical signs considered most likely to have resulted from a VAE, and represents a case of primarily neurological signs resolving spontaneously. Emphasis is given to the prevention and prompt recognition of this event and to the use of all available tools in the management of cardiovascular complications. 相似文献
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V. Palus B. Bladon T. Brazil G. B. Cherubini S. E. Powell T. R. C. Greet C. M. Marr 《Equine Veterinary Education》2012,24(8):415-422
This retrospective study summarises the case details, presenting signs, management and outcome in cases of temporohyoid osteoarthropathy (THO) and describes the findings of diagnostic imaging modalities. The condition appears to be relatively rare in Europe and the objective of this study is to make clinicians aware that THO can have a range of various neurological and clinical presentations. The records of 2 referral equine practices in England were reviewed and 7 horses with THO diagnosed on guttural pouch endoscopy indentified. The clinical and neurological signs, diagnostic procedures, treatment and outcomes were reviewed. Although small, this group is the largest case series of THO from Europe. One horse was a yearling, whereas THO is generally considered usually to affect middle aged and older horses. Computed tomography was used to confirm the diagnosis and demonstrated stylohyoid bone fractures in 2 cases while there was mild increased radionuclide uptake in one of 2 cases undergoing nuclear scintigraphy. Treatment is still controversial, although ceratohyoidectomy led to complete resolution of signs in 2 of 5 cases thus treated and improvement in the other 3. One horse with mild signs treated with antimicrobials and nonsteroidal anti‐inflammatory drugs made a full recovery while another, presented with head shaking and managed with a phased exercise programme, improved but did not resolve completely. 相似文献
14.
Calorific values and ash contents of different parts of Masson pine trees in southern China 总被引:1,自引:0,他引:1
Calorific value of plants is an important parameter for evalu- ating and indexing material cycles and energy conversion in forest eco- systems. Based on mensuration data of 150 sample sets, we analyzed the calorific value (CV) and ash content (AC) of different parts of Masson pine (Pinus massoniana) trees in southern China using hypothesis testing and regression analysis. CV and AC of different tree parts were almost significantly different (P〈0.05). In descending order, ash-free calorific value (AFCV) ranked as foliage 〉 branch 〉 stem bark 〉 root 〉 stem wood, and AC ranked as foliage 〉 stem bark 〉 root 〉 branch 〉 stem wood. CV and AC of stem wood from the top, middle and lower sections of trees differed significantly. CV increased from the top to the lower sections of the tnmk while AC decreased. Mean gross calorific value (GCV) and AFCV of aboveground parts were significantly higher than those of belowground parts (roots). The mean GCV, AFCV and AC of a whole tree of Masson pine were 21.54 kJ/g, 21.74 kJ/g and 0.90%, re- spectively. CV and AC of different tree parts were, to some extent, cor- related with tree diameter, height and origin. 相似文献
15.
Nitrification is the biological conversion of organic or inorganic nitrogen compounds from a reduced to a more oxidized state.
Denitrification is generally referred to as the microbial reduction of nitrate to nitrite and further gaseous forms of nitric
oxide, nitrous oxide and molecular nitrogen. They are functionally interconnected processes in the soil nitrogen cycle that
are involved in the control of long-term nitrogen losses in ecosystems through nitrate leaching and gaseous N losses. In order
to better understand how nitrification and denitrification change during the process of ecosystem restoration and how they
are affected by various controlling factors, gross nitrification rates and denitrification rates were determined using the
barometric process separation (BaPS) technique in subalpine coniferous forests of different restoration stages. The results
showed that forest restoration stage had no significant effects on gross nitrification rates or denitrification rates (One-way
ANOVA (analysis of variance), p < 0.05). There was no significant difference in the temperature coefficient (Q
10) for gross nitrification rate among all the forest sites (One-way ANOVA, p < 0.05). Gross nitrification rates were positively correlated with water content (p < 0.05), but not with soil pH, organic matter, total nitrogen, or C/N ratios. Denitrification rates in all the forest soils
were low and not closely correlated with water content, soil pH, organic matter, or total nitrogen. Nevertheless, we found
that C/N ratios obviously affected denitrification rates (p < 0.05). Results from this research suggest that gross nitrification is more responsible for the nitrogen loss from soils
compared with denitrification.
Translated from Journal of Plant Ecology, 2006, 30(1): 90–96 [译自: 植物生态学报] 相似文献
16.
Déo-Gratias J. M. Hougni Bénédicte Chambon Eric Penot Arunee Promkhambut 《Journal of Sustainable Forestry》2018,37(8):787-803
In order to alleviate poverty in Northeast Thailand, the Thai government has promoted rubber farming, which has expanded at the expense of annual crops. Because of a long immature period, planting rubber represents a loss of income for poor farmers in the very first years. This paper analyzed how rubber intercropping during the immature period helps farmers to compensate for this loss of income. Economic performances of the most widespread rubber farming systems were analyzed using information collected from a questionnaire addressed to 35 farmers in Buriram province. A sub-sample of 22 farmers was further interviewed to estimate the contribution of rubber intercropping in the formation of the total annual income during the immature period. The results showed that interest in rubber intercropping has grown, with cassava and rice as the main associated crops. With additional costs of about 14,169 ?/ha/year over monospecific rubber plantations, rubber-cassava intercropping systems generated a gross margin estimated at 11,340 ?/ha/year for a 3-year period. Compared to a monospecific rubber plantation, rubber-cassava intercropping systems reduced management costs by 59% over the 6-year period of rubber immaturity. The cash-income drawn from intercropping ranged from 0 to 26.8% of the household’s total annual income, which can be of considerable importance for low-income farmers. 相似文献
17.
Kyoichi Kumada 《Soil Science and Plant Nutrition》2013,59(1):106-111
I. Absorption Spectra of Some Artificial Humic Acids It is a well known fact that numerous dark brown or black and amorphous substances cap be produced from organic compounds by purely chemical processes. Some of them are called artificial humic acids, and have been used as a model of soil humic acids by many workers. But it is doubtful whether such artificial humic acids are considered to be a model of soil humic acids, even if there can be found any similarities in their properties. However it may be an useful method for the study of humus formation to compare artificial humic acids with soil humic acids, and to make efforts to find a good model or to prepare artificial humic acids comparable to soil humic acids under laboratory conditions. For this purpose, first of all, the author prepared artificial humic acids from glucose, hydroquinone and lignin, and their absorption spectra were determined. 相似文献
18.
该文以华北平原冬小麦为研究区,验证MODIS-GPP产品数据在下垫面复杂的农田生态系统的适用性,及农田生态系统的碳源/汇功能。首先采用MODIS-NDVI产品数据,根据冬小麦物候特征,解译出冬小麦种植面积;然后与经过验证并校正后的MODIS-GPP产品数据估算华北平原冬小麦2010年生长季内的GPP总量;最后,由涡度相关实测数据估算出冬小麦的生态系统呼吸量(RE)和净生态系统生产力(NEP)。结果显示:MODIS-NDVI解译出的冬小麦面积结果与TM解译结果的用户精度高达90.6%,总体精度达87.2%;MODIS-GPP产品数据与涡度相关数据估算结果的复相关系数高达0.9227;2010年华北平原冬小麦生长季GPP约为6.24′108 kgC,约占该区所有植被GPP的21.3%;华北平原冬小麦固碳能力较强,净生态系统生产力(NEP)占GPP的58.7%。研究表明,MODIS-GPP产品数据满足华北平原冬小麦GPP统计精度需求,冬小麦生态系统对陆地生态系统起到了重要的碳汇功能。 相似文献
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20.
基于自适应ARMA模型的区域农业总产值构成研究与应用 总被引:2,自引:0,他引:2
由于噪声的存在并随时间累积,传统的自回归滑动平均模型(ARMA模型)不能直接应用于时间序列的中期预测.该文针对这种情况,提出了一种自适应的自回归滑动平均模型,将模型状态划分为无噪声的迭代模型和有噪声的观察模型,并根据迭代模型的特点,详细推导并完整给出了它的迭代求解公式,以便使其可以用于时间序列的中期预测,同时研究1985~2001年黄淮海平原农业、牧业与渔业产值预测模型,得到较理想的预测结果.并用所建模型对2001年产值进行外延预测,以期为区域农业结构调整提供理论依据. 相似文献