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61.
Use of a spiral fiberoptic basket for the removal of adult heartworms from the vena cava and right atrium of a dog with postcaval syndrome is described. Complications reported with the use of alligator forceps were not encountered with the basket. 相似文献
62.
L. O. Howard 《Journal of pest science》1926,2(9):114-118
Ohne Zusammenfassung 相似文献
63.
Cheng Xiaoqin Ping Tain Li Zuzheng Wang Tian Han Hairong Epstein Howard E. 《New Forests》2022,53(1):125-142
New Forests - Plant functional traits have been shown to vary with environmental conditions. However, we lack empirical data on how plant functional traits of different plant life forms respond to... 相似文献
64.
Ontology-based simulation in agricultural systems modeling 总被引:1,自引:0,他引:1
A methodology and applications of ontology-based simulation are presented. An environment for building simulations based on the Lyra ontology management system is described which includes web-based visual design tools for constructing models and automatically generating simulation code. The ontology is used for representing all equations and all symbols appearing in these equations that are needed to describe a model. The example applications presented are models of soil, water, and nutrient management in citrus and sugarcane. Results thus far show that the ontology-based approach has advantages for representing the model structure, equations, and symbols, that complex models can be described in this format, and that efficient simulation code can be generated automatically from the ontology definition of the model. Potential applications, not yet fully explored, include ability to automatically connect models and data sources, using the ontology to organize model bases containing many models and model components, and using ontology reasoners to search for models, automatically discover model similarities and differences, and generate model instances from general principles. 相似文献
65.
D. Michael Jackson Howard F. Harrison Robert L. Jarret Philip A. Wadl 《Genetic Resources and Crop Evolution》2018,65(4):1217-1236
The United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Plant Genetic Resources Conservation Unit in Griffin, GA maintains the United States germplasm collection for Ipomoea spp. (Convolvulaceae). During 2012–2014, 737 sweetpotato, Ipomoea batatas (L.) Lam., plant introductions (PI) were acquired as tissue-culture plantlets and then acclimated to greenhouse conditions at the USDA, ARS, U. S. Vegetable Laboratory (USVL), Charleston, SC. Single plants were transferred to plastic-covered plant beds to produce cuttings for replicated field trials. Storage roots were harvested from 690 PIs grown in the field and 695 PIs grown in pots. Color coordinates were obtained for each PI using a tristimulus colorimeter. Hue angle values (h*) ranged from 8.2° to 88.3° (\( \bar{x} \) = 54.9°) for the periderm (peel or skin) of field-grown storage roots (n = 690 PIs) and ? 9.4° (= 350.6°) to 96.2° (\( \bar{x} \) = 51.3°) for pot-grown roots (n = 695 PIs). The red–green coordinate (a*) ranged from 0.8 to 30.7 (\( \bar{x} \) = 12.8) for the periderm of field-grown roots and ? 2.0 to 44.9 (\( \bar{x} \) = 16.1) for pot-grown roots. The yellow–blue coordinate (b*) ranged from 2.8 to 33.1 (\( \bar{x} \) = 19.4) for the periderm of field-grown roots and ? 7.4 to 38.1 (\( \bar{x} \) = 19.3) for pot-grown roots. Color saturation (chroma, C*) ranged from 13.7 to 35.8 (\( \bar{x} \) = 24.9) for the periderm of field-grown roots and 14.9–45.5 (\( \bar{x} \) = 29.3) for pot-grown roots. Lightness (white–black, L*) ranged from 32.6 to 81.7 (\( \bar{x} \) = 54.6) for the periderm of field-grown roots and 32.1–88.2 (\( \bar{x} \) = 64.0) for pot-grown roots. Hue angles ranged from ? 13.1° (= 346.9°) to 100.9° (\( \bar{x} \) = 80.9°) for the stele (flesh) of field-grown storage roots (n = 672 PIs) and ? 29.9° to 103.5° (\( \bar{x} \) = 81.6°) for pot-grown roots (n = 676 PIs); a* ranged from ? 5.6 to 35.0 (\( \bar{x} \) = 8.0) for the stele of field-grown roots and ? 6.0 to 41.0 (\( \bar{x} \) = 7.6) for pot-grown roots; and b* ranged from ? 7.7 to 56.1 (\( \bar{x} \) = 34.6) for the stele of field-grown roots and ? 12.6 to 56.1 (\( \bar{x} \) = 31.8) for pot-grown roots. C* ranged from 12.7 to 65.8 (\( \bar{x} \) = 37.2) for the stele of field-grown roots and 8.9–65.7 (\( \bar{x} \) = 34.5) for pot-grown roots; and L* ranged from 27.8 to 91.1 (\( \bar{x} \) = 77.7) for the stele of field-grown roots and 28.2–91.9 (\( \bar{x} \) = 80.4) for pot-grown roots. There were significant relationships between stele color (h*) and percent dry matter, with orange stele having a significantly lower % dry matter (\( \bar{x} \) = 25.6%, n = 183) compared with roots with cream/white stele (\( \bar{x} \) = 30.8%, n = 373). There appears to be wide genetic diversity for root color characteristics for the United States sweetpotato germplasm collection. 相似文献
66.
ABSTRACT This paper reviews current developments that facilitate increased access to food science information, with examples from the Web, from search engine producers, and from disseminators and producers of specialised abstracting and indexing (A&I) databases. The diversity of developments is reviewed in the context of blogs, wikis, Facebook, YouTube, Connotea, and examples of increasing Web access with Google Scholar and Windows Live Search Academic are provided. Examples of A&I search platform developments which are discussed include CSA Illustrata, EBSCOhost visual search, and ISI Web of Knowledge. A simple case study is included which indicates user preferences for search engines, databases, and search interface features for accessing food science information. It is concluded that information providers are successfully using a number of development strategies designed to help the food science information community with its needs. 相似文献
67.
【目的】比较不同提取方法对山苍子油提取效率与抗氧化活性的影响,通过 GC-MS分析,研究山苍子油成分构成与抗氧化活性的内在关联,分析山苍子油抗氧化活性的主要物质基础。【方法】采用液液萃取(分别加以超声波与磁化辅助处理)、二氧化碳超临界萃取以及水蒸气蒸馏法提取山苍子油,DPPH 法比较不同提取方式对山苍子油抗氧化活力的影响,GC-MS分析山苍子油的主要成分,并以1,4-二溴苯为内标,采用面积归化法解析主要成分的相对含量。【结果】山苍子油具有显著的抗氧化活性。液液萃取法的提取效率与山苍子油抗氧化活性最高,超声波辅助处理油得率最高,为26.3%,磁化辅助处理抗氧化活性最优,达到31.22 mg·mL -1( IC50),二氧化碳超临界萃取法次之,抗氧化活性为56.95 mg·mL -1( IC50),水蒸气蒸馏法抗氧化活性最弱,为64.95 mg·mL -1( IC50); GC-MS分析检测出122种以上的化合物,包括12种脂肪酸,16种萜烯,18种含氧萜烯以及其他微量化合物包括烯烃、醇、酮类与烷烃等。GC-MS分析结果表明:山苍子干果主要成分为饱和脂肪酸(月桂酸等)、不饱和脂肪酸(9,12-十八碳二烯酸、9-十八碳烯酸等)以及α蒎烯、β蒎烯、柠檬烯等萜烯、氧化萜烯类物质。液液萃取法得到的山苍子油脂肪酸含量(53.51%~66.61%)明显高于二氧化碳超临界萃取(17.64%)与水蒸气蒸馏法(8.1%),而二氧化碳超临界萃取与水蒸气蒸馏法得到的萜烯、氧化萜烯类含量分别达到29.37%和17.69%,明显高于液液萃取法(6.49%~9.75%)。【结论】磁化辅助处理有利于抗氧化活性物质的提取,且不饱和脂肪酸的含量最高;超声波辅助处理可以提升油的得率;水蒸气蒸馏法和超临界流体萃取法更有利于萜烯类化合物的获取;联系到水蒸气蒸馏法得到的山苍子油富含萜烯化合物却显示较低的抗氧化活性(64.95 mg·mL -1 ),色谱级的柠檬醛抗氧化活性最低(74.33 mg·mL -1),因此推测脂肪酸成分(特别是不饱和脂肪酸)是山苍子油抗氧化活性的主要物质基础。 相似文献
68.
Landscape environmental features, such as disturbance susceptibility, biological diversity and aesthetics, depend on the forest spatial structure and on the characteristics of its component stands. Strategies for forestland classification are key for managing for spatial heterogeneity as they provide the setting for the layout of land use activities. The design of management units boundaries may further contribute to meet specific spatial conditions. In this paper, two alternative land-classification strategies are presented. They are applied to one test forest with about 12,000 ha. The forest management is constrained by the definition of an exclusion period — the minimum number of years between clearcuts of adjacent management units. Land transformation and fragmentation by harvest scheduling over a temporal horizon with eight ten-year periods is analyzed within the framework of each strategy. Landscape mosaics in each planning period are characterized by spatial statistics, such as the number of patches, average patch area, and the amount and type of edge and interior space. Results from three test computer runs are discussed. They show that land classification has a substantial impact on the spatial dynamics of the forested landscape. They further suggest that timber opportunity costs are not sensitive to the strategy used to classify the land as long as a scheduling model is used to help in management planning. 相似文献
69.
Sanghun Lee Howard J. Woodard James J. Doolittle 《Soil Science and Plant Nutrition》2013,59(6):823-832
Some South Dakota soils contain high levels of available selenium (Se) for crop uptake. A field study was conducted to determine if any popular wheat (Triticum aestivum) varieties demonstrate differential Se uptake. A total of 280 samples including eight winter wheat and ten spring wheat varieties were analyzed for grain Se concentration and uptake for two growing years. Soil samples were sequentially fractionated into (1) plant available (0.1?M KH2PO4 extractable) and (2) conditionally available (4?M HCl extractable) pools and analyzed separately for total Se. Selenium concentration in wheat grain had a wide variability and the mean value over two years was 0.63?µg?Se?g?1. Grain Se concentration and Se uptake were not significantly different by wheat varieties tested in this study. Grain Se concentration was significantly correlated with soil Se levels, soil pH, and orthophosphate-P content within a location, but grain Se concentration was strongly influenced by geographical location in which different amounts of soil Se bioavailability occurred. 相似文献
70.