全文获取类型
收费全文 | 199篇 |
免费 | 14篇 |
国内免费 | 1篇 |
专业分类
林业 | 36篇 |
农学 | 1篇 |
13篇 | |
综合类 | 15篇 |
农作物 | 7篇 |
水产渔业 | 14篇 |
畜牧兽医 | 112篇 |
园艺 | 2篇 |
植物保护 | 14篇 |
出版年
2022年 | 7篇 |
2021年 | 8篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 10篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 20篇 |
2012年 | 12篇 |
2011年 | 27篇 |
2010年 | 11篇 |
2009年 | 10篇 |
2008年 | 12篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 8篇 |
2003年 | 9篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1996年 | 1篇 |
排序方式: 共有214条查询结果,搜索用时 15 毫秒
31.
Akio Koizumi Jun-ichi Motoyama Kei Sawata Yoshihisa Sasaki Takuro Hirai 《Journal of Wood Science》2010,56(3):189-193
To estimate the wind force that causes windthrow damage to a tree, the drag coefficients of actual-sized trees were evaluated
by a field test method. In this method, wind velocity and stem deflection were monitored simultaneously. The wind force acting
on a tree crown was calculated from stem deflection; stem stiffness was evaluated by conducting tree-bending tests. The results
of tests conducted on three poplar trees showed that drag coefficient decreased with an increase in wind velocity. Although
the variation in the drag coefficient was large at low wind velocity because of the vibrating behavior of the stem subjected
to variable wind force, the variation at wind velocities above 10 m/s was small. The average drag coefficient at a wind velocity
of 30 m/s was estimated by the curve-fitting of a power function to the wind velocity-drag coefficient relationship to be
0.102, which was smaller than that of actual-sized conifers studied in previous wind tunnel experiments. The drag coefficients
of these crown areas in the defoliation season were smaller than those measured in the leafy season. 相似文献
32.
Earth's solid inner core is mainly composed of iron (Fe). Because the relevant ultrahigh pressure and temperature conditions are difficult to produce experimentally, the preferred crystal structure of Fe at the inner core remains uncertain. Static compression experiments showed that the hexagonal close-packed (hcp) structure of Fe is stable up to 377 gigapascals and 5700 kelvin, corresponding to inner core conditions. The observed weak temperature dependence of the c/a axial ratio suggests that hcp Fe is elastically anisotropic at core temperatures. Preferred orientation of the hcp phase may explain previously observed inner core seismic anisotropy. 相似文献
33.
Peng WANG Kousaku SOUMA Yuki KOBAYASHI Kei IWABUCHI Chihiro SATO Takayoshi MASUKO 《Animal Science Journal》2010,81(4):487-493
This study examined the differences between non‐inoculated (control) corn and Northern Leaf Blight (NLB)‐damaged corn (inoculated corn); dry matter (DM) yield, silage fermentation quality, nutritive value and feed intake by sheep were compared. Leaf, stem and grain dry weights and gross yield of inoculated corn were significantly (P < 0.05) decreased compared with control corn. The contents of water‐soluble carbohydrate and nitrogen‐free extract (NFE) were decreased in inoculated corn compared with control corn. Silage made from both inoculated and control corn showed good fermentation quality. The digestibility of DM, organic matter, ether extract, NFE, and energy of silage made from inoculated corn were significantly (P < 0.05) lower, and contents of total digestible nutrients (TDN) and digestible energy (DE) were also significantly (P < 0.05) lower compared with silage made from the control corn. DM intake showed no significant discrepancy between the two types of silage. TDN and DE intakes from inoculated silage were significantly (P < 0.05) lower compared with control silage. From the above results it was shown that NLB caused a decrease in DM yield and NFE content in corn and a decrease in the nutritive value and feed intake of silage. 相似文献
34.
35.
Shinohara T Ishii K Kanatsu-Shinohara M 《The Journal of reproduction and development》2011,57(2):288-295
Stem cells of the side population (SP) phenotype are found in many self-renewing tissues and can be identified by their unique ability to effectively exclude the dye Hoechst 33342. We previously established a method for expanding spermatogonial stem cells (SSCs) in vitro, but the frequency of SSCs is only about 1 to 2%, limiting detailed SSC analyses. In this study, we sought to isolate SSCs from in vitro cultures by exploiting their ability to exclude Hoechst 33342. In contrast to the findings of previous in vivo studies, we found that SP cells developed in a stochastic manner in vitro. Moreover, SP cells in culture were not enriched in SSCs, but they were interconvertible with non-SP cells. Although SP cells were consistently found in testes after transplantation of cultured cells, they were not enriched in SSCs. These results show that SSCs have an unstable SP phenotype and provide evidence that SSCs change their phenotype characteristics in response to their microenvironment. 相似文献
36.
Hayashi K Bhandal J Kim SY Rodriguez CO Entwistle R Naydan D Kapatkin A Stover SM 《Veterinary surgery : VS》2011,40(2):192-197
Objectives: To (1) describe vascular distribution in the grossly intact canine cranial cruciate ligament (CCL) using immunohistochemical techniques specific to 2 components of blood vessels (factor VIII for endothelial cells, laminin for basement membrane); and (2) compare the vascularity in different areas of interest (craniomedial versus caudolateral bands; core versus epiligamentous regions; and proximal versus middle versus distal portions) in the intact normal canine CCL. Study Design: In vitro study. Animals: Large, mature dogs (n=7) of breeds prone to CCL disease that were euthanatized for nonorthopedic conditions. Methods: Intact CCL were collected from fresh canine cadavers free from stifle pathology. CCL tissue was processed for immunohistochemistry and stained for factor VIII and laminin. Vascular density was determined by histomorphometric analysis. Results: Specific vascular staining was sparsely identified throughout the CCL; however, the proximal portion of the CCL appears to have a greater number of vessels than the middle or distal portion of the ligament. Conclusions: The CCL is a hypovascular tissue and its vascular distribution is not homogeneous. 相似文献
37.
Takehiro Hachiken Kei Sato Takahiro Hasegawa Katsuyuki Ichitani Makoto Kawase Kenji Fukunaga 《Genetic Resources and Crop Evolution》2013,60(4):1559-1570
To elucidate diversity and evolution of the Waxy gene in foxtail millet, Setaria italica, we analyzed sequence polymorphism of Waxy gene in 83 foxtail millet landraces collected from various regions covering the entire geographical distribution of this millet in Europe and Asia. We found a unique geographic distribution pattern at the sequence level of gene haplotypes and also found a large diversity in East Asian landraces. We also found a higher degree of genetic polymorphism in a non-waxy phenotype than in other low amylose types, supporting the hypothesis that low amylose types recently originated from non-waxy type. 相似文献
38.
Toru Taniguchi Yasunori Ohmiya Manabu Kurita Miyoko Tsubomura Teiji Kondo Yong Woo Park Kei’ichi Baba Takahisa Hayashi 《Journal of Wood Science》2008,54(5):408-413
We performed biosafety assessments of transgenic poplars prior to field trials. Constitutive expression of the Aspergillus aculeatus xyloglucanase in Populus alba increased the cellulose content and specific gravity of its stem, the leaves of which were visibly greener, thicker, and
smaller than those of the wild-type plant. Although the young transgenic poplars grew faster than the wild type in a growth
chamber, there was no distinguishable difference in growth between the poplars when they were placed in a special screened
greenhouse. Allelopathic tests showed that the transgenic poplars do not produce harmful substances. Based on all the biosafety
assessments and the scientific literature on poplar species, we came to the conclusion that transgenic poplars probably do
not disturb the biological diversity of the surrounding environment, even when they are submitted to field trials. 相似文献
39.
Kei Kondo 《Journal of Pesticide Science》2022,47(3):146
The extrapolability of the lysimeter test as a dissipation simulator in an actual paddy field was evaluated using mathematical models and their inverse analyses for predicting pesticide fate and transport processes in paddy test systems. As a source of experimental data, a four-year comparative experiment in lysimeters and paddy fields was conducted using various paddy pesticides. First, the dissipations for various active ingredients in granule pesticides under submerged applications were statistically compared using simple kinetic modeling. Second, the dissipation pathways, unobserved experimental components, and effect of the experimental setting were evaluated using a higher tier mathematical model with a novel inverse analysis protocol. Finally, owing to experimental constraints, the unobtainable parameters were extracted from the laboratory container test before being transferred to compare the outdoor experimental data under different formulation types. 相似文献
40.
Effect of a single polymorphism in the Japanese quail NK‐lysin gene on antimicrobial activity
下载免费PDF全文
![点击此处可从《Animal Science Journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Taichiro Ishige Hiromi Hara Takashi Hirano Tomohiro Kono Kei Hanzawa 《Animal Science Journal》2016,87(1):143-146
NK‐lysins are cationic peptides that play important roles in host protection, and are an important constituent of innate immunity. We identified nine single‐nucleotide polymorphisms (SNPs) in the NK‐lysin open reading frame (ORF) from 32 Japanese quails in six strains: A, B, ND, K, P, and Y. The G to A substitution at nucleotide position 272 in the ORF resulted in a Gly (G) to Asp (D) amino acid substitution (Cj31G and Cj31D alleles). The Cj31D allele was detected in P (frequency 0.76) and Y (frequency 0.03) strains. We compared the antimicrobial activities of four synthetic peptides from the helix 2‐loop‐helix 3 region of avian NK‐lysins against Escherichia coli: Cj31G and Cj31D from quail and Gg29N and Gg29D from chicken. The antimicrobial activities of the four peptides decreased in the following order: Gg29N > Cj31G > Gg29D > Cj31D (P < 0.05). Although there were no differences in the predicted secondary structure of the Cj31G and Cj31D, the net charge of the Cj31G was higher than that of Cj31D. These data indicated that the antimicrobial activity of CjNKL is influenced by net charge, similar to that which has been observed in chicken. © 2015 Japanese Society of Animal Science 相似文献