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91.
Charles Santhanaraju Vairappan Takahiro Ishii Tan Kai Lee Minoru Suzuki Zhan Zhaoqi 《Marine drugs》2010,8(6):1743-1749
In our continuous interest to study the diversity of halogenated metabolites of Malaysian species of the red algal genus Laurencia, we examined the chemical composition of five populations of unrecorded Laurencia sp. A new brominated diterpene, 10-acetoxyangasiol (1), and four other known metabolites, aplysidiol (2), cupalaurenol (3), 1-methyl-2,3,5-tribromoindole (4), and chamigrane epoxide (5), were isolated and identified. Isolated metabolites exhibited potent antibacterial activities against clinical bacteria, Staphylococcus aureus, Staphylococcus sp., Streptococcus pyogenes, Salmonella sp. and Vibrio cholerae. 相似文献
92.
93.
The incidence and severity of resinous stem canker disease were investigated in hinoki (Chamaecyparis obtusa) and sawara (C. pisifera) at a progeny test located in Yamatsuri Town, Fukushima Prefecture, Japan. Symptoms of the disease were observed in 307 trees
out of 933 investigated trees (32.9%). The damage was more severe on lower slopes than on upper slopes, indicating that micro-environmental
factors are causally associated with the occurrence of the disease. The severity of the disease varied both among nine open-pollinated
progenies derived from hinoki plus-tree clones and among 13 progenies derived from pollination between hinoki plus-tree clones
and the mixed-pollen of hinoki plus-tree clones. The severity of the disease also varied with height above the ground. This
tendency was most obvious where the disease was most severe. An estimation of the narrow sense heritability,h
2, of 0.214, was obtained from analysis of the 13 progenies derived from pollination with mixed-pollen. The heritability derived
from material that had not been subjected to selection against the disease, indicated that breeding to enhance resistance
would be possible to control the disease. The interaction between environments and progenies in relation to severity of the
disease is also discussed.
Ms. Setsuko Chiba and Mr. Mamoru Ueta gave us vigorous supports, and Mr. Haruki Orita, Dr. Tomiyasu Miyaura, and Dr. Shinichiro
Ito gave us many helpful comments. We deeply appreciated their cooperation. The study was supported by a grant from the Ministry
of Agriculture, Forestry. and Fisheries of Japan. 相似文献
94.
Masato Yoshida Osamu Yamamoto Takashi Okuyama Yutaka Tamai Yuzou Sano Minoru Terazawa 《Journal of Wood Science》1999,45(5):361-367
Although it is well known that sap exudation during early spring in temperate deciduous trees occurs in response to daytime warming and nighttime cooling, the mechanisms of the process are not yet fully understood. Previous theories suggested that changes in stress in the wood caused by daytime heating and nighttime cooling might be linked with sap flow. Consequently, a study of itaya-kaede maple (Aver mono) and shirakamba birch (Betula platyphylla var.japonica) looked at tangential strains. One-hour intervals for 3 years of the tangential strains on the inner bark of stem and root were measured in itaya-kaede maple and shirakamba birch during the sap exudation season. The measurements indicated different mechanisms of sap exudation in these two trees. During the sap exudation season in late March, when the temperature fluctuated around 0°C, the tangential strain in the root of itaya-kaede maple showed expansion in the daytime and contraction at night. Conversely, in early April the tangential strain in the root of shirakamba birch exhibited contraction in the daytime and expansion at night. The changes in tangential strains in itaya-kaede maple were attributed to conditioning, a known concept used to explain the uptake mechanism of soil water in maple and its exudation during early spring. However, because the change in tangential strain in the roots of shirakamba birch was similar to that found during the rampant season, sap exudation was not attributed to conditioning but to the plentiful supply of water from the roots. The implications of these mechanisms are that different sap harvesting techniques may be appropriate for different tree species. 相似文献
95.
Sakae Horisawa Masahide Sunagawa Yutaka Tamai Yuki Matsuoka Tohru Miura Minoru Terazawa 《Journal of Wood Science》1999,45(6):492-497
The physical properties of sawdust including porosity, water retention, and water drainage were analyzed to prove its suitability for use as an artificial soil in the automatic decomposer-extinguisher (GADE) machine. The physical and chemical properties of residual sawdust from the GADE machine were also analyzed, the mechanical abrasion of sawdust in the GADE machine was tested, and the morphology of this residue was observed through a scanning electron microscope to investigate changes of these properties in the medium of decomposing garbage. Sawdust, which showed a lower specific gravity and larger porosity than soil, is considered capable of supplying air to bacteria. It was found that sawdust became worn from the operation of the machine. The spaces of residual sawdust were still observed, but water drainage decreased. The portion of hollocellulose in residual sawdust decreased, although the extractives in it increased. Results indicated that the capacity of sawdust to function as an artificial soil in the GADE machine was decreased owing not only to the destruction of sawdust grain but also to the adherence of products from decomposition, such that sawdust needed to be replaced every few months.Part of this report was presented at the 43rd annual meeting of the Japan Wood Research Society, Morioka, April 1993 相似文献
96.
Minoru Kadota Shinsuke Torisawa Tsutomu Takagi Kazuyoshi Komeyama 《Fisheries Science》2011,77(6):993-998
We explore how a stochastic model provides the most promising avenue towards predicting fish movement. To construct a stochastic
model describing fish movement, trajectories of ten juveniles in a water tank were analyzed from a stochastic point of view.
The heading angle was defined as a random variable. Our analysis found that the most probable forward heading angle was between
0° and 22.5° (probability ~78%), followed by angles between 22.5° and 45° (probability ~10%). We also found that the choice
of future heading angle depends on the current heading angle. Therefore, we treated heading angle state as a first-order Markov
process and constructed a correlated random walk model describing juvenile movement in a water tank. Our stochastic model
simulated a trajectory similar to observed trajectories. We used the model as a tool for estimating the probability distribution
of potential fish path outcomes. We derived the distribution of potential outcomes from a large number of simulations (N = 1000) and investigated these trajectories. We collected a set of juvenile trajectories that collided with the tank and
estimated the probability of juvenile collisions with the tank. 相似文献
97.
Kelly Vargas Yoshiho Asakura Minoru Ikeda Nobuhiko Taniguchi Yasuhiro Obata Katsuyuki Hamasaki Kotaro Tsuchiya Shuichi Kitada 《Fisheries Science》2008,74(3):533-543
ABSTRACT: Allozyme variation of the littleneck clam Ruditapes philippinarum was evaluated in four samples from Nameishi and Matsuo in the Ariake Sea, Ryugatake and Ushibuka in the Shiranui Sea off Kyushu Island, Japan, and in one sample from Jinzhou, China, in the Bohai Sea. A Ruditapes bruguieri sample imported from the Korean Bay off Nampo, North Korea was also studied. Among the R. philippinarum samples, heterozygosity varied from 0.265 to 0.301 and F IS estimates indicated significant homozygosity excess in 15 of 40 loci analyzed. Deviations from Hardy–Weinberg equilibrium were significant in all samples ( P < 0.05). Pairwise F ST estimates indicate that genetic differences between the Chinese and Japanese samples were very low, but significantly different from zero. Mixture proportions with 95% confidence intervals of Chinese R. philippinarum in Nameishi and Matsuo were estimated at 0.4098 [0.2512, 0.5705] and 0.4899 [0.3262, 0.6540], respectively. However, genetic invasion of stocked Chinese R. philippinarum into wild populations in the Ariake Sea remains uncertain due to the low precision of the estimates caused by the high similarity of allele frequencies between Jinzhou and the Ariake Sea. 相似文献
98.
Mami ADACHI Hirotaka IGARASHI Minoru OKAMOTO Takashi TAMAMOTO Yasutomo HORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):296
A 10-year-old female Cavalier King Charles Spaniel presented with hematuria, pollakiuria and skin rash. Based on the histopathological and cytological examination of the skin and bladder mucosa, the dog was diagnosed with large granular lymphocytic (LGL) lymphoma of the bladder and skin. The dog responded well to the initial chemotherapy with nimustine for 3 months. Since recurrence of skin erosion and bladder wall thickening were observed, the dog was subsequently administered chemotherapy with other anticancer drugs, including chlorambucil, vincristine, doxorubicin, L-asparaginase, cytosine arabinoside, and cyclophosphamide. The dog survived for 11 months and died due to tumor-related disseminated intravascular coagulation. This is the first report of a canine case of LGL lymphoma in the skin and bladder. 相似文献
99.
Miho Kojima Fabio Minoru Yamaji Hiroyuki Yamamoto Masato Yoshida Takahisa Nakai 《Forest Ecology and Management》2009
Climate change resulting from increased atmospheric carbon dioxide (CO2) and shortages of fossil fuels such as petroleum are major problems worldwide. Under these conditions, demand for woody biomass resources is increasing. We investigated the feasibility of using fast-growing Eucalyptus grandis for material production. Samples of E. grandis were collected from four plantations in different latitude divisions, including tropical and subtropical Brazil and subtropical Argentina. Various xylem qualities were measured and related to the lateral growth rate. Lateral growth rate did not significantly affect the longitudinal released strain of the surface growth stresses or the xylem density at any of the sampling sites. Higher lateral growth rate, higher values of xylem density, and lower absolute values of the released strain were observed in plantations closer to the equator. Higher growth rates in tropical climate promote longer fiber length. In subtropical plantations, smaller diameter trees will produce tension wood with smaller microfibril angles. Planting E. grandis closer to the equator thus produces higher quality wood than in plantations at lower latitudes. 相似文献
100.
Periodic cell arrangements of tracheids in Cryptomeria japonica and Agathis sp., and that of wood fibers in Magnolia obovata were examined by Fourier transform image analysis (FTIA). The angular distribution functions on power spectral patterns (PSPs) transformed from the dot maps were traced. As well as this conventional method, we developed the line convolution method and domain transformation for more correct analysis of radial and tangential arrangements. Cell arrangements became clear in Cryptomeria and Agathis. Fluctuations were expressed by the standard deviation (σ) or the relative standard deviation (σr) so that we could compare the characteristics of both woods. In Cryptomeria, the most provable distance between tracheids along radial files was 36.7 µm with 17% fluctuation, whereas the tangential interval was 28.3 µm with σr of 24%. In Agathis, the radial diameter was 35.1 µm with σr of 23% and the tangential interval was 41.5 µm with σr of 23%. In Magnolia, the maximal periodicity of wood fibers was 15.8 µm and 20.5 µm along and between radial files, respectively, although the fluctuations could not be estimated because of the remarkable interruptions by numerous vessels. 相似文献