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排序方式: 共有893条查询结果,搜索用时 15 毫秒
821.
GIS-based modeling of Javan Hawk-Eagle distribution using logistic and autologistic regression models 总被引:4,自引:0,他引:4
Few attempts have been made to model the distribution of the Javan Hawk-Eagle (Spizaetus bartelsi) based on predictions formulated from habitat requirements in West Java or throughout Java Island. This paper proposes a new approach to predicting probability models of Javan Hawk-Eagle (JHE) distribution using the application of logistic regression (LR) and autologistic regression (ALR) coupled with RAMAS GIS, and creating pseudo-absence data using a normalized difference vegetation index from remote sensing data. Habitat requirements of 11 nest-sites in Gunung Gede-Pangrango National Park (TNGP) and its surrounding areas were analyzed and quantified, and the model was validated in southern parts of West Java. The final LR model was used as the starting point for fitting ALR models that account for spatial autocorrelation through the addition of an autocovariate variable using several different neighborhood sizes ranging from 450 m (15 × 15 moving window size, or equal to 20.25 ha) to 1500 m (50 × 50 moving window size, or equal to 225 ha) using 300 m interval. The best model was the ALR model with a 1500 m autocovariate that agreed with the distance between nests in TNGP and the mean home range size in Java. This model showed a significant increase in overall accuracy and successfully removed misclassified pixels. Based on our results, we recommend five strategies for the management and conservation of JHE habitat, including integrated conservation management and increased regulation of wildlife reserves. 相似文献
822.
Shimizu-Ibuka A Nakai Y Nakamori K Morita Y Nakajima K Kadota K Watanabe H Okubo S Terada T Asakura T Misaka T Abe K 《Journal of agricultural and food chemistry》2008,56(13):5338-5344
Neoculin occurring in an edible tropical fruit is a heterodimeric protein which has both sweetness and a taste-modifying activity that converts sourness to sweetness. Both the primary and the overall tertiary structures of neoculin resemble those of monocot mannose-binding lectins. This study investigated differences in biochemical properties between neoculin and the lectins. Structural comparison between the mannose-binding sites of lectins and the corresponding regions of neoculin showed that there is at least one amino acid substitution at each site in neoculin, suggesting a reason for the lack of its mannose-binding ability. This was consistent with hemagglutination assay data demonstrating that neoculin had no detectable agglutinin activity. DNA microarray analysis indicated that neoculin had no significant influence on gene expression in Caco-2 cell, whereas kidney bean lectin (Phaseolus vulgaris agglutinin) greatly influenced various gene expressions. These data strongly suggest that neoculin has no lectin-like properties, encouraging its practical use in the food industry. 相似文献
823.
Individual detection of genetically modified maize varieties in non-identity-preserved maize samples
Akiyama H Sakata K Kondo K Tanaka A Liu MS Oguchi T Furui S Kitta K Hino A Teshima R 《Journal of agricultural and food chemistry》2008,56(6):1977-1983
In many countries, the labeling of grains and feed- and foodstuffs is mandatory if the genetically modified organism (GMO) content exceeds a certain level of approved GM varieties. The GMO content in a maize sample containing the combined-trait (stacked) GM maize as determined by the currently available methodology is likely to be overestimated. However, there has been little information in the literature on the mixing level and varieties of stacked GM maize in real sample grains. For the first time, the GMO content of non-identity-preserved (non-IP) maize samples imported from the United States has been successfully determined by using a previously developed individual kernel detection system coupled to a multiplex qualitative PCR method followed by multichannel capillary gel electrophoresis system analysis. To clarify the GMO content in the maize samples imported from the United States, determine how many stacked GM traits are contained therein, and which GM trait varieties frequently appeared in 2005, the GMO content (percent) on a kernel basis and the varieties of the GM kernels in the non-IP maize samples imported from the United States were investigated using the individual kernel analysis system. The average (+/-standard deviation) of the GMO contents on a kernel basis in five non-IP sample lots was determined to be 51.0+/-21.6%, the percentage of a single GM trait grains was 39%, and the percentage of the stacked GM trait grains was 12%. The MON810 grains and NK603 grains were the most frequent varieties in the single GM traits. The most frequent stacked GM traits were the MON810xNK603 grains. In addition, the present study would provide the answer and impact for the quantification of GM maize content in the GM maize kernels on labeling regulation. 相似文献
824.
Kondoh Tadashi Nagasaka Yoshisada Kato Atushi Shindo Hayato Kato Masaya Saito Masanori Fujiwara Koki Yamamoto Satoshi Yaji Yukio 《Paddy and Water Environment》2019,17(2):221-230
Paddy and Water Environment - We measured nutrient inflows and outflows on reclaimed land (157 km2, including 100 km2 of paddy fields) in Lake Hachiro. The net effluent loads... 相似文献
825.
Study on aquifer hydraulic properties using tidal response method for future groundwater development
Shirahata Katsushi Yoshimoto Shuhei Tsuchihara Takeo Ishida Satoshi 《Paddy and Water Environment》2019,17(3):531-537
Paddy and Water Environment - The hydraulic properties of an island’s aquifers were studied using a tidal response method. Groundwater is the principal water resource on the studied island,... 相似文献
826.
Our goal was to predict the spatial distribution of canopy species composition in secondary deciduous hardwood forests at
a fine spatial resolution, based on climatic and topographical factors using a geographic information system. We studied secondary
forests on Mt. Gozu, Niigata Prefecture, central Japan. Canopy species composition was investigated in 100 sample plots within
the study area. A digital elevation model (DEM) was created, and topographical, hydrological, and light factors were calculated
using the DEM. Climatic factors were interpolated by kriging. The five major species used as response variables were Fagus crenata, Quercus serrata, Quercus crispula, Magnolia obovata, and Castanea crenata. We prepared three possible explanatory variable sets: climatic variables only, both climatic and topographic variables,
and topographic variables only. Multivariate regression trees were derived, and the accuracy of predicting the major species
composition was tested. The multivariate regression trees derived from the climatic variable set and from the climatic and
topographic variable set had better accuracy than the regression tree derived from the topographic variable set. In the regression
tree generated by the climatic and topographic variable set, the warmth index was the principal explanatory variable in classifying
forest types, followed by topographic factors. This regression tree would be preferable to the other two regression trees
for the prediction of canopy species composition. 相似文献
827.
Toshiharu Enomae Yoon-Hee Han Akira Isogai Michihisa Hotate Satoshi Hasegawa 《Journal of Wood Science》2010,56(5):395-402
Laid lines are observed frequently in Japanese paper. For restoration of historic document paper, the laid line intervals
should be consistent between the restoration paper and the original paper for harmonized appearance. Considering this prerequisite,
the perception mechanisms of the laid lines are discussed. Laid lines can be easily observed against backlight. However, there
are several cases where laid lines are not visible against backlight, but are clearly visible with diffuse reflected light.
With paper sheets formed on screens with short bamboo splint pitches, laid lines were observed only with diffuse reflected
light. Within these sheets, there was no fiber mass distribution or surface roughness that correlated with the periodicity
of the laid lines. On the other hand, paper sheets produced using long splint pitches exhibited light transmission unevenness,
fiber mass unevenness, and surface roughness. Microscopic observations using two-way low-angle illumination revealed the following
mechanism. In the flow sheet-forming method, fibers are oriented strongly in the cross-splint direction in the first layer
while some fibers rotate and become aligned along the interspaces between the splints in the second layer during dehydration.
Bidirectionally oriented fibers perpendicular to each other result in a contrasting reflectivity perceived as laid lines. 相似文献
828.
829.
Satoshi Kagiwada Yusuke Kayano Hideo Hoshi Takeshi Kawanishi Kenro Oshima Hiroshi Hamamoto Hiromichi Horie Shigetou Namba 《Journal of General Plant Pathology》2010,76(5):345-347
In summer 2007, leaf and stem rot of ice plants was found in a hydroponic greenhouse in Japan. The causal agent was a fungus
identified as Choanephora cucurbitarum (Berkeley & Ravenel) Thaxter, based on pathogenicity, morphology, mating tests, and sequence analysis of the ribosomal DNA
ITS region. 相似文献
830.
Changes in the morphology and functions of vacuoles provide useful information about the mechanism of cell death. In the present study, we monitored the morphology and contents of vacuoles during the death of ray parenchyma cells in the conifer Cryptomeria japonica. In differentiating xylem, ray parenchyma cells had large central vacuoles. In sapwood, vacuoles in ray parenchyma cells contained proteins, an indication that one of the main functions of these vacuoles might be protein storage. A dramatic decrease in the protein content of some vacuoles was detected in the intermediate wood before the initiation of vacuole rupture. Although vacuole rupture was detected from the intermediate wood to the outermost heartwood, some vacuoles were obviously enlarged in the inner intermediate wood. Condensed nuclei were first observed after the rupture of these large vacuoles in ray parenchyma cells. It seems plausible that the autolysis of the contents of ray parenchyma cells might be caused by the rupture of the enlarged vacuoles in the inner intermediate wood. 相似文献