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891.
892.
In order to provide useful genomic information for agronomical plants, we have established a database, the Kazusa Marker DataBase (http://marker.kazusa.or.jp). This database includes information on DNA markers, e.g., SSR and SNP markers, genetic linkage maps, and physical maps, that were developed at the Kazusa DNA Research Institute. Keyword searches for the markers, sequence data used for marker development, and experimental conditions are also available through this database. Currently, 10 plant species have been targeted: tomato (Solanum lycopersicum), pepper (Capsicum annuum), strawberry (Fragaria × ananassa), radish (Raphanus sativus), Lotus japonicus, soybean (Glycine max), peanut (Arachis hypogaea), red clover (Trifolium pratense), white clover (Trifolium repens), and eucalyptus (Eucalyptus camaldulensis). In addition, the number of plant species registered in this database will be increased as our research progresses. The Kazusa Marker DataBase will be a useful tool for both basic and applied sciences, such as genomics, genetics, and molecular breeding in crops. 相似文献
893.
Abnormal morphology in megalopae of the swimming crab,Portunus trituberculatus during seed production: causes and prevention
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Shigeki Dan Yuming Sui Takaaki Kaneko Satoshi Takeshima Daisuke Ojima Tatsuo Miyoshi Kaoru Hamano Masakazu Ashidate Katsuyuki Hamasaki 《Aquaculture Research》2016,47(10):3189-3202
The occurrence of morphologically immature megalopae, which retain zoeal features such as dorsal spines and furcae of telson, is closely correlated with larval mass mortality during seed production of the swimming crab Portunus trituberculatus in Japanese hatcheries. To determine the cause of immature megalopal morphology, zoeae were reared with various supplementary schedules and density of diets (rotifer, Artemia and phytoplanktons including Chlorella vulgaris and Nannochloropsis oculata). In addition, to assess the relationship between immature morphology and endocrine control, the effect of causative dietary factor was compared with the effect of eyestalk ablation at various timing during zoeal development. Megalopal immature morphology was more distinct in Chlorella‐supplemented groups than in Nannochloropsis‐supplemented groups. High density Chlorella supplementation was associated with the highest incidence of immaturity and resulted in larval mass mortality. The premoult of the third zoeal stage was identified as a critical period at which Chlorella supplementation led to the highest incidence of immaturity. This critical period coincided with the critical period at which larval metamorphosis was regulated by the eyestalk neurosecretory system. Our results suggested that the occurrence of immature megalopal morphology under culture conditions is most likely caused by phytoplankton (especially, Chlorella) supplementation, which disrupts the endocrine regulation. On the basis of our results, we successfully prevented the occurrence of immature megalopal morphology in 500 L tanks by excluding the influence of phytoplankton before the critical period (i.e. discontinuing phytoplankton supplementation and supplying rotifer cultured with non‐phytoplankton materials). 相似文献
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895.
896.
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
897.
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
898.
899.
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
900.