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101.
Ishikawa K Takenaga K Akimoto M Koshikawa N Yamaguchi A Imanishi H Nakada K Honma Y Hayashi J 《Science (New York, N.Y.)》2008,320(5876):661-664
Mutations in mitochondrial DNA (mtDNA) occur at high frequency in human tumors, but whether these mutations alter tumor cell behavior has been unclear. We used cytoplasmic hybrid (cybrid) technology to replace the endogenous mtDNA in a mouse tumor cell line that was poorly metastatic with mtDNA from a cell line that was highly metastatic, and vice versa. Using assays of metastasis in mice, we found that the recipient tumor cells acquired the metastatic potential of the transferred mtDNA. The mtDNA conferring high metastatic potential contained G13997A and 13885insC mutations in the gene encoding NADH (reduced form of nicotinamide adenine dinucleotide) dehydrogenase subunit 6 (ND6). These mutations produced a deficiency in respiratory complex I activity and were associated with overproduction of reactive oxygen species (ROS). Pretreatment of the highly metastatic tumor cells with ROS scavengers suppressed their metastatic potential in mice. These results indicate that mtDNA mutations can contribute to tumor progression by enhancing the metastatic potential of tumor cells. 相似文献
102.
Shintaro Imamura Michiko Suzuki Emiko Okazaki Yuko Murata Meiko Kimura Takashi Kimiya Yoshinobu Hiraoka 《Fisheries Science》2012,78(1):177-185
Thaw-rigor is often found in frozen meat of bigeye tuna Thunnus obesus. Excessive amounts of drip loss and stiffness greatly lower the commercial value of tuna meat. In order to prevent thaw-rigor
in meat stored at −60°C post-capture, we adapted a temperature shift technique that stores the meat at −7°C for 1 day or −10°C
for 7 days before thawing. Biochemical changes in muscle of bigeye tuna before and after the temperature shift to −7 or −10°C
were characterized. Contents of ATP, NAD+, glycogen, and creatine phosphate decreased after the temperature shift. NAD+ levels decreased faster than ATP levels and were highly correlated with the rigor index. Thaw-rigor occurred in muscle containing
NAD+ at 1 μmol/g and ATP at 7 μmol/g. On the other hand, the meat color of tuna during frozen storage changed to brown depending
on the storage temperature and reflected the rate of metmyoglobin (met-Mb) formation. Met-Mb formation increase was dependent
on the decrease in NADH levels during the frozen storage. A temperature shift technique with storage at −7°C for 1 day or
−10°C for 7 days before thawing prevented thaw-rigor and met-Mb formation. 相似文献
103.
104.
Maoka T Akimoto N Tsushima M Komemushi S Mezaki T Iwase F Takahashi Y Sameshima N Mori M Sakagami Y 《Marine drugs》2011,9(8):1419-1427
Carotenoids of the corals Acropora japonica, A. secale, and A. hyacinthus, the tridacnid clam Tridacna squamosa, the crown-of-thorns starfish Acanthaster planci, and the small sea snail Drupella fragum were investigated. The corals and the tridacnid clam are filter feeders and are associated with symbiotic zooxanthellae. Peridinin and pyrrhoxanthin, which originated from symbiotic zooxanthellae, were found to be major carotenoids in corals and the tridacnid clam. The crown-of-thorns starfish and the sea snail D. fragum are carnivorous and mainly feed on corals. Peridinin-3-acyl esters were major carotenoids in the sea snail D. fragum. On the other hand, ketocarotenoids such as 7,8-didehydroastaxanthin and astaxanthin were major carotenoids in the crown-of-thorns starfish. Carotenoids found in these marine animals closely reflected not only their metabolism but also their food chains. 相似文献
105.
106.
107.
108.
Miho Kojima Hiroyuki Yamamoto S. Nugroho Marsoem Takashi Okuyama Masato Yoshida Takahisa Nakai Saori Yamashita Koichiro Saegusa Kenji Matsune Kentaro Nakamura Yoshihiko Inoue Takeshi Arizono 《Annals of Forest Science》2009,66(5):507-507
109.
Eitaro Fukatsu Yuichiro Hiraoka Noritsugu Kuramoto Hiroo Yamada Makoto Takahashi 《Annals of Forest Science》2018,75(4):96
Key message
Accurate evaluation of genetic performances of trees is crucial in order to improve the efficiency of forest tree breeding. We revealed that spatial analysis is effective for predicting individual tree breeding values at the forward selection stage of Cryptomeria japonica D. Don (sugi) breeding program by using a novel validation approach.Context
In the process of selecting genetically superior trees for breeding, appropriate handling of environmental effects is important in order to precisely evaluate candidate trees. Spatial analysis has been an effective statistical approach for genetic evaluation at sites with heterogeneous microenvironments. However, the efficiency of spatial analysis on forward selection has not been validated on a practical scale to date.Aims
This study aimed to reveal the effectiveness of spatial analysis, which incorporates spatially autocorrelated residuals into mixed models, for the prediction of breeding values at the forward selection stage by validation using progeny or clonal tests of forward-selected individuals.Methods
Tree height was analyzed by ordinary randomized complete block design models and spatial models incorporating spatially autocorrelated residuals in a linear mixed model framework, and model selection was conducted at thirty Cryptomeria japonica D. Don breeding population sites having various topographical ruggedness. For validation, three clonal tests and one progeny test of individuals selected from three and four breeding populations, respectively, were used. The effectiveness of forward selection using the two models was evaluated based on the correlation between individual breeding values at the stage of forward selection and genotypic and breeding values that were estimated by clonal and progeny tests.Results
Spatial models were more predictive than ordinary models in all cases. Spatial correlation parameters tend to increase with the topographical ruggedness index of each site. The correlation coefficients between breeding values at the time of forward selection and genotypic or breeding values evaluated in succeeding clonal and progeny tests were significantly higher in spatial models than in ordinary models in six out of nine cases.Conclusion
Validation using progeny and clonal tests of forward-selected individual trees revealed that spatial analysis is more effective for the evaluation of genetic performance of individuals at the stage of forward selection in Cryptomeria japonica.110.
R Matsuda M Ishibashi M Uchiyama T Hiraoka H Hoshida Y Kunihiro H Miki Y Nishimoto K Inazu T Mizuno 《Journal of the Association of Official Analytical Chemists》1987,70(4):681-686
Determination of organic compounds present as contaminants in purified water is of great importance. Total organic carbon (TOC) may be a useful parameter for evaluating the purity of water. This paper describes and compares the analytical results for solutions of 12 model compounds obtained by 3 methods: total organic carbon (TOC) analysis, determination of potassium permanganate consumption, and UV spectroscopy. TOC analysis gave values corresponding to the expected amounts of organic carbon for all the model compounds, whereas the other 2 methods gave highly variable results. 相似文献