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61.
Hiroyuki Matsunari Hiroshi Hashimoto Kentaro Oda Yoshitsugu Masuda Hitoshi Imaizumi Kazuhisa Teruya Hirofumi Furuita Takeshi Yamamoto Kazuhisa Hamada Keiichi Mushiake 《Aquaculture Research》2013,44(11):1696-1705
The effect of docosahexaenoic acid (DHA) on the growth performance, survival and swim bladder inflation of larval Seriola dumerili during the rotifer feeding period was investigated in two feeding experiments. Amberjack larvae at 3 day post hatching were fed rotifers enriched with (1) freshwater C hlorella (Chlo), (2) a mixture (2:1, v/v) of Chlo and DHA‐enriched C hlorella (DHA‐Chlo), (3) DHA‐Chlo and (4) DHA‐Chlo and commercial DHA emulsion, in triplicate for 7 days. The average DHA contents of the rotifers were 0.0, 0.4, 1.0 and 1.9 mg g?1 DM respectively. The survival rate was improved by the enrichment of rotifers with DHA‐Chlo alone, and DHA‐Chlo and emulsion. Growth and swim bladder inflation of fish fed rotifers enriched with DHA‐Chlo were significantly (P < 0.05) improved, however, with increased levels of DHA further improvement was not found. DHA content in the larval whole body proportionally increased with the DHA level in the rotifers. These results suggest that DHA enrichment of rotifers is effective to improve the growth, survival rate and swim bladder inflation of amberjack larvae. The DHA requirement of amberjack larvae is estimated to be 1.5 mg g?1 on a dry matter basis of rotifers. 相似文献
62.
Hideaki Endo Tadayoshi Muramatsu Goro Yoshizaki Huifeng Ren Hitoshi Ohnuki 《Fisheries Science》2012,78(2):391-398
A label-free immunosensor for detecting the oocyte maturation-inducing hormone 17, 20β-dihydroxy-4-pregnen-3-one (DHP), was
developed. A principle of the sensor system was based on differences in electrochemical activity changed by an immunoreaction
in the absence and presence of DHP. For preparation of the immunosensor, anti-DHP IgG was immobilized on an Au working electrode
modified with a self-assembled monolayer of 3-mercaptopropionic acid. The sensor was immersed into a sample solution containing
DHP. DHP was determined by cyclic voltammetry. The immunosensor showed a specific response to DHP, and the oxidation peak
current linearly decreased in the range of 7.8–500 pg ml−1 with a correlation coefficient of 0.996. The sensor system was applied to determine the DHP levels in plasma of goldfish
and was compared with the DHP levels of the same samples determined using an ELISA as the conventional method. Good correlation
was obtained between values determined using both methods in the range of 0.1–7.7 ng ml−1 (correlation coefficient 0.876). These findings suggest that the proposed label-free immunosensor can be used to analyze
DHP levels in fish plasma samples. 相似文献
63.
Jin‐Long Yang Shu‐Heng Li Wei‐Yang Bao Hideki Yamada Hitoshi Kitamura 《Aquaculture Research》2015,46(1):155-162
Metamorphic responses of pediveliger larvae of Mytilus galloprovincialis to different ions were investigated through a series of bioassays. Effects of tetraethylammonium chloride (TEA) on inductive effects of these above ions were also investigated. Excess ions including Li+, Cs+, Rb+ and Ca2+ induced larval metamorphosis at 10?3 M to 5 × 10?2 M in 24‐h exposure assays. In continuous exposure assays, only excess Ca2+ showed inductive activity and induced 25% metamorphosis at 5 × 10?2 M. Larval responses to Li+ and Rb+were inhibited by TEA, while induction of metamorphosis by Cs+and Ca2+ was independent of the presence of TEA. Thus, these ions used can be useful inducers of larval metamorphosis for application in the aquaculture industry. The finding provides new insights on the biochemical mechanism controlling larval metamorphosis in this species. 相似文献
64.
Masako Kubo Koji Shimano Hitoshi Sakio Yuji Isagi Keiichi Ohno 《Journal of Forest Research》2010,15(5):337-340
Cercidiphyllum japonicum and C. magnificum are deciduous tree species that produce large numbers of sprouts. They are found mainly in riparian and/or disturbed areas.
C. japonicum is distributed in the montane zone in Japan, whereas C. magnificum is distributed mostly in the subalpine zone of central Japan. However, the two species sometimes coexist, e.g., on the talus
slope at the valley head of the Chichibu Mountains. We investigated differences in sprouting traits in these two species by
comparing class distributions of sprout diameter at breast height (DBH) and heights of individuals on the talus slope. Sprout
DBH and individual height were smaller in C. magnificum as compared to C. japonicum. Moreover, the analysis of the DBH-class distribution of each species indicated that C. magnificum had numerous small sprouts and experienced high mortality, whereas C. japonicum had fewer small sprouts and low mortality. It is likely that the sprouting traits of C. magnificum make it more adapted to severe conditions in the subalpine zone than those of C. japonicum. 相似文献
65.
Masahiko Mori Kento Maki Tsubasa Kawahata Daigo Kawahara Yuta Kato Toru Yoshida Hidetaka Nagasawa Hitoshi Sato Atsushi J. Nagano Paul C. Bethke Kiyoaki Kato 《Breeding Science》2021,71(2):208
Epicotyl length (ECL) of adzuki bean (Vigna angularis) affects the efficiency of mechanized weeding and harvest. The present study investigated the genetic factors controlling ECL. An F2 population derived from a cross between the breeding line ‘Tokei1121’ (T1121, long epicotyls) and the cultivar ‘Erimo167’ (common epicotyls) was phenotyped for ECL and genotyped using simple sequence repeats (SSRs) and single-nucleotide polymorphism (SNP) markers. A molecular linkage map was generated and fifty-two segregating markers, including 27 SSRs and 25 SNPs, were located on seven linkage groups (LGs) at a LOD threshold value of 3.0. Four quantitative trait loci (QTLs) for ECL, with LOD scores of 4.0, 3.4, 4.8 and 6.4, were identified on LGs 2, 4, 7 and 10, respectively; together, these four QTLs accounted for 49.3% of the phenotypic variance. The segregation patterns observed in F5 residual heterozygous lines at qECL10 revealed that a single recessive gene derived from T1121 contributed to the longer ECL phenotype. Using five insertion and deletion markers, this gene was fine mapped to a ~255 kb region near the end of LG10. These findings will facilitate marker-assisted selection for breeding in the adzuki bean and contribute to an understanding of the mechanisms associated with epicotyl elongation. 相似文献
66.
Kemmochi S Fujimoto H Woo GH Hirose M Nishikawa A Mitsumori K Shibutani M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(5):655-664
We have shown phosphoinositide 3-kinase (PI3K)/Akt signaling activation in thyroid capsular invasive carcinomas (CICs), which are highly induced by promotion with sulfadimethoxine (SDM) in a rat 2-stage thyroid carcinogenesis model. To examine the potency of calcitriol, a synthetic vitamin D3 analog, on the development or progression of CICs, male F344 rats were injected with calcitriol (0.1 μg/kg body weight) three times a week intraperitoneally, during an entire period of SDM-promotion for 13 weeks (Experiment 1) or during the last 2 weeks of a 15-week SDM-promotion (Experiment 2). Initiation with N-bis(2-hydroxypropyl)nitrosamine preceded all treatments. In Experiment 1, long-term calcitriol treatment reduced the multiplicity of CICs, while cell proliferation activity, estimated by Ki-67 cell index in the induced CICs, was unchanged with SDM-promotion alone. Considering the strong dependency of promotion with SDM during the early stages on thyroid-stimulating hormone, the reduced multiplicity in Experiment 1 may be due to the effect on an early stage of neoplastic proliferation. Although the magnitude was mild, cell proliferation activity was decreased in existing CICs after short-term calcitriol treatment in Experiment 2, which was associated with a mild decrease in cyclin-dependent kinase-2-positive cells, cytoplasmic immunolocalization of phosphorylated, inactive, Rb protein and a mild increase in nucleocytoplasmic expression of p27(kip1). Although the effect was mild at the late stage of SDM-promotion in this hypothyroidism-related thyroid carcinogenesis model, our results suggest that calcitriol targets cell proliferation via inhibition of a molecular cascade downstream of PI3K/Akt signaling, controlling G1/S transition. 相似文献
67.
Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage
Nakano K Matsunari H Nakayama N Ogawa B Kurome M Takahashi M Matsumoto M Murakami H Kaji Y Nagashima H 《The Journal of reproduction and development》2011,57(2):312-316
The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer. 相似文献
68.
Michishita M Akiyoshi R Yoshimura H Katsumoto T Ichikawa H Ohkusu-Tsukada K Nakagawa T Sasaki N Takahashi K 《Research in veterinary science》2011,91(2):254-260
There is increasing evidence for the presence of cancer stem cells in several solid tumors, and these cancer stem cells have a potential role in tumor initiation, aggression, and recurrence. The stem cell-like properties of spheres derived from canine mammary tumors remain largely elusive. We attempted to induce sphere formation using four cell lines of canine mammary adenocarcinoma, and characterized the spheres derived from a CHMp line in vitro and in vivo. The CHMp-derived spheres showed predominantly CD44+CD24− population, higher expression of stem cell-related genes, such as CD133, Notch3 and MDR, and higher resistance to doxorubicin compared with the CHMp-derived adherent cells. Xenograft transplantations in nude mice demonstrated that only 1 × 104 sphere cells were sufficient for tumor formation. Use of the sphere assay on these sphere-derived tumors showed that sphere-forming cells were present in the tumors, and were maintained in serial transplantation. We propose that spheres derived from canine mammary adenocarcinoma cell lines possess a potential characteristic of cancer stem cells. Spheres derived from canine mammary tumors could be a powerful tool with which to investigate novel therapeutic drugs and to elucidate the molecular and cellular mechanisms that underlie tumorigenesis. 相似文献
69.
70.
To raise more rice in Japan we have placed much fertilizers in the fields, thus the soils often have been degraded by the leaching of essential elements including Fe to such a extent as rice roots are injured by the H2S produced by the reduction of sulphates. It has been encouraged by law to place non-sulphate fertilizers and iron compounds in these fields. 相似文献