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31.
Asami Nakanishi Yoshiyuki Inagaki Naoya Osawa Shozo Shibata Kei’ichi Hirata 《Journal of Forest Research》2009,14(6):388-393
Leaf nitrogen nutrition of hinoki cypress (Chamaecyparis obtusa Endlicher) was investigated at three positions along a slope over a period of 3 years. At each slope position, nitrogen properties
were compared in patch-cut plots (0.06–0.09 ha) and uncut control plots (0.04 ha). Nitrogen cycling at the lower slope was
characterized by a higher rate of soil nitrogen mineralization, and higher nitrogen concentration in fresh leaves and leaf-litter.
The soil nitrogen mineralization rate and fresh-leaf nitrogen concentration in the patch-cut plots were higher than those
in the control plots. However, leaf-litter nitrogen concentration did not differ between the patch-cut and control plots.
The results suggest that slope position strongly affects leaf nitrogen nutrition of hinoki cypress and soil nitrogen availability.
By contrast, patch cutting does not affect leaf-litter nitrogen concentration. These findings indicated that hinoki cypress
would not enhance forest nitrogen cycling through changes in leaf-litter nitrogen concentration after patch cutting. 相似文献
32.
The body size of juvenile fish is often used as an index of growth rate, which in turn is influenced by local habitat conditions. We evaluated the size and origin of juvenile Chum salmon Oncorhynchus keta in the coastal areas of three regions (Atsuta, Shari, and Konbumori) of Hokkaido, northern Japan. The origin of the individuals in these communities differed between Konbumori and the other two regions. The former contained juveniles that originated from both the nearest stocked river and other rivers that were outside the area of interest. Conversely, the communities in Atsuta and Shari consisted exclusively of fish from the nearest stocked river. Moreover, the juveniles in Konbumori were larger than those in Atsuta and Shari. The results of our otolith analysis suggest that the larger size of the fish in Konbumori was due to the immigration of large individuals from natal rivers at distant locations. Thus, immigrants were likely to enlarge their body size composition in the area of interest. In summary, if the distance from a natal river is adjusted and daily growth is taken into account, body size can be used as an indicator of growth performance in coastal juvenile chum salmon. 相似文献
33.
Taichiro Ishige Hiromi Hara Takashi Hirano Tomohiro Kono Kei Hanzawa 《Animal Science Journal》2017,88(9):1249-1257
The Japanese quail has several advantages as a low‐fat meat bird with high immunity against diseases. Cathelicidins (CATHs) are antimicrobial peptides that play an important role in innate immunity. The aim of this study was to characterize the CATH cluster in the Japanese quail (Coturnix japonica). The Japanese quail CATH (CjCATH) cluster, contains four CATH genes, as in the chicken. The coding sequences of CjCATHs exhibited >85.3% identity to chicken CATHs. The predicted amino acid sequences of the four CjCATH genes contained the cathelin‐like domain characteristic of CATH proteins. Polymorphisms were detected in the open reading frames (ORFs) of all CjCATH sequences. Two amino acid substitutions were observed in the antimicrobial region of the mature peptide of CjCATH2, and predicted to influence peptide function. CjCATH1 is expressed in lung, heart, bone marrow and bursa of Fabricius (BF). CjCATH2 is expressed in bone marrow. CjCATH3 is expressed in lung, heart, bone marrow, BF, tongue and duodenum. CjCATHB1 is expressed in bone marrow and BF. This study is the first to characterize CATH genes in the Japanese quail, and identifies novel antimicrobial peptide sequences belonging to the cathelicidin family, which may play a role in immunity in this species. 相似文献
34.
Kei Nakagawa Shin-Ichiro Wada Ryoma Kitamura Ronny Berndtsson 《Communications in Soil Science and Plant Analysis》2017,48(21):2594-2600
Groundwater pollution by nitrate from agricultural fields is a worldwide problem. To improve the understanding of nitrate transport processes through volcanic ash soils overlying groundwater aquifers, salt sorption experiments were performed. Salt sorption is the process that involves the simultaneous use of cation and anion adsorption mechanisms without changing the pH. Prepared six different concentrations of potassium chloride (KCl) solutions were mixed with soil samples. Anion and cation contents of the liquid and solid phases were determined. Experiments were performed in triplicate of six kinds of KCl solutions for three types of soils. Thus, total 54 of samples were analyzed. Relationships between ionic strength and sorption capacity increments of cations and anions were determined. The results show that if ionic strength of the infiltrating solution to the volcanic ash soil is known, the ECEC (effective cation exchange capacity) and EAEC (effective anion exchange capacity) can be reliably estimated. The resulting prediction equations can be included to improve reactive transport simulation models. Consequently, it will be possible to better understand solute transport with changing sorption capacity for the solid soil phase. 相似文献
35.
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
36.
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
37.
Fumie MAGATA Mitsuo ISHII Eri OIKAWA Hidefumi FURUOKA Kazutaka YAMADA Naoki SASAKI Syo SHIMIZU Hisashi INOKUMA 《Journal of Equine Science》2010,21(2):17-20
A 42-day-old heavy draft horse fell into sudden astasia. Significant swelling and heat
sensation of the left femoral region were observed. Because of a friction sound in the
left hip, we supposed that the hip joint was dislocated or the hip bone was fractured.
Computed Tomography (CT) examination showed that the left hip joint was dislocated and the
left femoral head was disjunct. We carried out a pathological autopsy, and made a
diagnosis of the foal as fracture of the hip bone and femoral head with suppurative
umbilical arteritis. Pathologic changes in the umbilical artery and hind leg were
completely unilateral, suggesting that left umbilical arteritis spread to the blood
circulation, causing arthritis and dislocation of the hip bone. 相似文献
38.
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
39.
40.
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