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排序方式: 共有480条查询结果,搜索用时 171 毫秒
61.
62.
Akiho KATAYAMA Ayako MIYAZAKI Naohito OKAZAKI Teruko NAKAYAMA Osamu MIKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):931
A total of ten 1–2-year-old rabbits died within 2 weeks at a facility in Ehime prefecture in May 2019. Necropsy revealed liver discoloration and fragility, hemorrhage of some organs and blood coagulation failure. On histopathologic examination, necrotizing hepatitis was a common finding, together with fibrin thrombi in the small vessels and hemorrhage in some organs. Rabbit hemorrhagic disease (RHD) virus gene was detected in liver samples, and viral particles of approximately 32 nm in diameter were found in the cytoplasm of degenerated hepatocytes by electron microscopy. Phylogenetic analysis based on the partial VP60 gene sequence classified it as Lagovirus europaeus GI.2/RHDV2. This is the first confirmed outbreak of RHD caused by globally emerging GI.2/RHDV2 in Japan. 相似文献
63.
At 114 ranches in the Hidaka District of Hokkaido, a total of 1,118 Thoroughbred foals
that were born from January to June 2003 were examined at different times from May to
September of the same year to ascertain the occurrence of clubfoot. Clubfoot was seen in a
total of 179 foals (16%) at 89 ranches (78%). Also, 124 of the 179 foals (69.3%) had
clubfoot of grade II or higher, and it was found that grade I was likely to be overlooked
or rapidly advance. In the present study, the occurrence of clubfoot was higher than
expected in the investigated region. Hence, it is necessary to establish accurate
diagnostic techniques and clubfoot guidelines to minimize the impact. 相似文献
64.
Toru TANIUCHI Takayuki KANAYA Shuuichi UWABE Takahito KOJIMA Seiji AKIMOTO Isamu MITANI 《Fisheries Science》2004,70(5):845-851
ABSTRACT: Age and growth of alfonsino Beryx splendens (Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length [FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows: L t = 542 {1 − exp [−0.133( t + 2.00)]}, where L t is fork length (mm) at yearly age t . The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan. 相似文献
65.
中日森林文化比较研究及启示 总被引:1,自引:0,他引:1
日本是一个森林大国,拥有着丰富的森林资源和森林文化,其教训和经验对中国乃至全世界的后工业化国家都有着很大的启发和借鉴意义。对日本的森林状况进行回顾和评价,从其森林思想中汲取精华,不断挖掘森林文化所蕴藏的丰富含义,恢复和弘扬森林文化,这对中国正在开展的生态文明建设以及解决环境问题都能提供思考和帮助。 相似文献
66.
67.
谢序福 《金陵科技学院学报》1995,(4)
介绍了日本大阪栽培葡萄采用棚架上盖薄膜、疏果、掐穗尖、叶面喷肥、喷赤霉素等方法取得了稳产优质的效果和通过农协切磋技艺及推销产品的经验。分析了南京葡萄栽培和采收中的问题。提出了控制产量、保证优质、修剪果穗,推迟采收、叶面喷肥、秋施基肥、推行棚架、加强冬管等一系列改进措施。 相似文献
68.
宋凡圣 《浙江大学学报(农业与生命科学版)》1992,(3)
作者从中国皇家宫苑、寺院丛林、自然山水园和私家文人园四个方面系统而全面地论述了中国园林及其对日本的影响,并以日本国仿效中国造园的具体事例,证明中国园林对日本造园艺术的影响尤为深刻. 相似文献
69.
Seiki Takatsuki 《Biological conservation》2009,142(9):1922-1929
The Japanese sika deer Cervus nippon has expanded its range by nearly 70% during the last two decades. Browsing by sika deer affects vegetation in both agricultural and forested habitats. Effects of sika deer on vegetation are conspicuous on deer-inhabited islands: forest structure and composition are altered by deer grazing and browsing, and consequently regeneration is prevented. By felling of old trees, forest gaps are formed, but since sapling recruitment is prevented, shade intolerant plants invade. Unpalatable forbs like ragwort Senecio cannabifolius and ferns like bracken Pteridium aquilinum (Dennstaedtiaceae) become dominants in open habitats. At the places of highest deer density, the Zoysia japonica community, a low growing grass mat, develops. Sika deer function as a seed dispersal agent of this grass. Indirect effects of sika deer are not well studied, but some studies have shown reduction of understory bamboo cover, which in turn improves the survival of tree seedlings and declines of wood mice Apodemus spp. Japanese forests in lower mountainous areas were widely logged during the 1940s and 1950s. These areas were not well planted during the war and until 1950, but thereafter intensively planted to alter to conifer plantation as a nationwide campaign. For several decades after the war, rodents and hares grazed planted trees. According to growth of the planted trees to form canopy, which is unfavorable for rodents and hares, their damage declined. After the 1960s, old-growth forests in high mountainous areas were logged, and conifers were planted. Animals causing forestry damage were replaced by sika deer during the 1980s. Sika deer eat a wide variety of foods, and are gregarious, which causes heavy impacts on vegetation. Effects of sika deer are expanding to natural forests, alpine vegetation, and marshes. To reduce damages on forestry and natural vegetation, as many as 100,000 sika deer are culled every year. However, the hunter population is rapidly declining, and it is expected population control by culling will be insufficient. Although sika deer are an important component of Japanese forests, current population densities exceed the capacity of many ecosystems to tolerate herbivory. 相似文献
70.