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91.
92.
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
93.
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
94.
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
95.
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
96.
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
97.
Yuto SANO Kazuya MATSUDA Minoru OKAMOTO Kazushige TAKEHANA Kazuko HIRAYAMA Hiroyuki TANIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):287-291
Antigen-presenting cells (APCs) in the uveal tract participate in ocular immunity including immune
homeostasis and the pathogenesis of uveitis. In horses, although uveitis is the most common ocular disorder,
little is known about ocular immunity, such as the distribution of APCs. In this study, we investigated the
distribution of CD163-positive and MHC II-positive cells in the normal equine uveal tract using an
immunofluorescence technique. Eleven eyes from 10 Thoroughbred horses aged 1 to 24 years old were used.
Indirect immunofluorescence was performed using the primary antibodies CD163, MHC class II (MHC II) and CD20.
To demonstrate the site of their greatest distribution, positive cells were manually counted in 3 different
parts of the uveal tract (ciliary body, iris and choroid), and their average number was assessed by
statistical analysis. The distribution of pleomorphic CD163- and MHC II-expressed cells was detected
throughout the equine uveal tract, but no CD20-expressed cells were detected. The statistical analysis
demonstrated the distribution of CD163- and MHC II-positive cells focusing on the ciliary body. These results
demonstrated that the ciliary body is the largest site of their distribution in the normal equine uveal tract,
and the ciliary body is considered to play important roles in uveal and/or ocular immune homeostasis. The data
provided in this study will help further understanding of equine ocular immunity in the normal state and might
be beneficial for understanding of mechanisms of ocular disorders, such as equine uveitis. 相似文献
98.
99.
Norio Kurihara Matazaemon Uchida Toshio Fujita Minoru Nakajima 《Pesticide biochemistry and physiology》1974,4(1):12-18
Penetration of BHC isomers through the integument of Periplaneta americana (L.) is a composite of several first-order events. Translocation and accumulation in the head appears to be a zero-order function. The correlation of some of the biological properties with physicochemical properties such as partition coefficients and binding constants are discussed. 相似文献
100.
Matazaemon Uchida Yasuo Irie Toshio Fujita Minoru Nakajima 《Pesticide biochemistry and physiology》1975,5(3):253-257
Nereistoxin suppressed the excitatory actions of α- and γ-BHC and HEOD in the central nervous system of Periplaneta americana (L.). However, it did not affect the neurotoxic action of DDT and DBrDT. Since nereistoxin is an acetylcholine antagonist, it is postulated that BHC and HEOD act to produce high level of acetylcholine and the resulting after-discharges, while DDT and DBrDT seem to attack the noncholinergic region of insect nervous system. 相似文献