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81.
Kuwata K Shibutani M Kemmochi Y Taniai E Morita R Ogawa B Mitsumori K 《Journal of toxicologic pathology》2010,23(3):151-155
In this report, we describe a case of neuroendocrine carcinoma of undetermined origin in a dog. Necropsy revealed scattered small neoplastic nodules in the bilateral lungs and a small nodule in the parapancreatic lymph node. Histopathologically, both pulmonary and lymph nodal nodules showed a similar histologic pattern, with neoplastic cells being arranged in diffusely proliferating sheet-like cellular nests separated by variable amounts of fibrous septa, sometimes forming rosettes and duct-like structures. Scattered small necrotic foci and invasion to fibrous septa were typically observed. Neoplastic cells showed round to oval-shaped nuclei with prominent nucleoli and abundant eosinophilic cytoplasm that were positive for Grimelius' silver impregnation staining and immunostaining with cytokeratin, synaptophysin, vasoactive intestinal peptide and chromogranin A, indicative of the development of a neuroendocrine carcinoma. However, judging from the distribution of tumors lacking the portion suggestive of the primary site in any organ examined, as well as no further indication of differentiation potential of neoplastic cells, this tumor has so far been diagnosed as neuroendocrine carcinoma of undetermined origin. 相似文献
82.
83.
Morphological changes in the cytoskeleton, nuclei, and vacuoles were monitored during the cell death of short-lived ray tracheids
in the conifer Pinus densiflora. After formation of the dentate thickenings that occurred at the final stage of formation of cell walls, organelles started
to disappear in differentiating ray tracheids. First, the microtubules and vacuoles disappeared. Then actin filaments disappeared
in the differentiating ray tracheids adjacent to ray tracheids that lacked nuclei, and, finally, the nuclei disappeared. These
features indicate that cell death in ray tracheids might differ from the programmed cell death of tracheary elements that
has been studied in vitro in the Zinnia culture system.
This study was presented at the 57th Annual Meeting of the Japan Wood Research Society, August 8–10, 2007, Hiroshima, Japan 相似文献
84.
Nobuko Saigusa Sheng-Gong Li Hyojung Kwon Kentaro Takagi Lei-Ming Zhang Reiko Ide Masahito Ueyama Jun Asanuma Young-Jean Choi Jung Hwa Chun Shi-Jie Han Takashi Hirano Ryuichi Hirata Minseok Kang Tomomichi Kato Joon Kim Ying-Nian Li Takahisa Maeda Akira Miyata Yasuko Mizoguchi Shohei Murayama Yuichiro Nakai Takeshi Ohta Taku M. Saitoh Hui-Ming Wang Gui-Rui Yu Yi-Ping Zhang Feng-Hua Zhao 《Journal of Forest Research》2013,18(1):41-48
The datasets of net ecosystem CO2 exchange (NEE) were acquired from 21 forests, 3 grasslands, and 3 croplands in the eastern part of Asia based on the eddy covariance measurements of the international joint program, CarboEastAsia. The program was conducted by three networks in Asia, ChinaFLUX, JapanFlux, and KoFlux, to quantify, synthesize, and understand the carbon budget of the eastern part of Asia. An intercomparison was conducted for NEE estimated by three gap-filling procedures adopted by ChinaFLUX, JapanFlux, and KoFlux to test the range of uncertainty in the estimation of NEE. The overall comparison indicated good agreement among the procedures in the seasonal patterns of NEE, although a bias was observed in dormant seasons depending on the different criteria of data screening. Based on the gap-filled datasets, the magnitude and seasonality of the carbon budget were compared among various biome types, phenology, and stress conditions throughout Asia. The annual values of gross primary production and ecosystem respiration were almost proportional to the annual air temperature. Forest management, including clear-cutting, plantation, and artificial drainage, was significant and obviously affected the annual carbon uptake within the forests. Agricultural management resulted in notable seasonal patterns in the crop sites. The dataset obtained from a variety of biome types would be an essential source of knowledge for ecosystem science as well as a valuable validation dataset for modeling and remote sensing to upscale the carbon budget estimations in Asia. 相似文献
85.
Atsushi Yoshimoto 《Journal of Forest Research》1996,1(2):67-72
In the past studies on the Gentan probability theory, economic factors, such as the price of logs and the interest rate, have
not been embedded into the derived stochastic model due to the limitation of the underlying assumptions. This has lead to
misleading results of economic analysis for harvesting behavior based on the Gentan probability theory. In this paper, economic
analysis of harvesting behavior was conducted by extending the Gentan probability theory. Since the proposed stochastic process
can incorporate a nonstationary growth function, economic analysis of harvesting behavior was easily implemented. Experimental
analysis of economic factors showed that change in the price of logs, the interest rate and harvest related costs affected
the Gentan probability distribution. Although the analysis is still hypothetical, the results imply the potential use of the
Gentan probability theory to predict the forest owners' harvesting behavior. 相似文献
86.
Yusuke Yamagishi Takenao Sato Hiromu Uchiyama Joto Yoshimoto Remi Nakagawa Satoshi Nakaba Takafumi Kubo Ryo Funada 《Journal of Wood Science》2012,58(6):557-562
Differentiated cells were recognized in calli derived from needles of Torreya nucifera and in calli derived from immature zygotic embryos of Cryptomeria japonica. Some differentiated cells resembled tracheary elements of primary xylem with spiral or reticulate thickening of cell walls. Other cells resembled tracheary elements with thick cell walls and bordered pits, which are features of secondary xylem. These tracheary elements were formed in cell clusters. Tracheary elements in calli of T. nucifera formed more highly developed structures, such as bordered pits and spiral thickening, than those of C. japonica. Cultured cells derived from conifers might provide a good model for studies of the differentiation of secondary xylem in vitro. 相似文献
87.
The structure of Japanese timber markets has changed drastically during recent decades. After the introduction of a large
amount of imported softwood products. Japanese timber producers have faced global competition with foreign timber suppliers
such as Canada, the US, and recently Nordic countries. In this paper, we present a forest sector model for lumber markets
with a focus on eight aggregate regions (Tohoku, Kanto, Hokuriku, Chubu, Kinki, Chugoku, Shikoku, and Kyushu) in Japan. The
proposed model is based on the Samuelson-partial equilibrium formulation, which searches for an optimal solution by maximizing
the net social payoff subject to demand and supply constraints. A nonlinear programming solution technique is incorporated
into the proposed model. Three types of lumber are considered,i.e., domestic lumber, the lumber processed in Japan from imported logs, and imported lumber from the US and Canada. Using data
for 1998, our analysis indicates that the derived equilibrium solution has a higher price for the imported lumber supply in
all regions, and a lower price for the other two products in most regions than the actual current price in 1998. The derived
net social payoff gains 1.6% compared with the one derived with the current set of prices and quantities.
This is research was supported by the Grant-in-Aid for scientific Research (No.11691090) from the Ministry of Education, Culture,
Science, Sports, and Technology of Japan. 相似文献
88.
Masashi Konoshima Charles W. McKetta Atsushi Yoshimoto 《Journal of Forest Research》2008,13(6):331-337
Forestry joint production choices require clear relative values for multiple, and often conflicting, management objectives.
Optimization is most difficult where values of forest attributes are: intangible, non-market, or sensitive. When most mathematical
programming models are adapted for non-commensurable objectives, there is little guarantee that vague relative preference
sets are met. We demonstrate how an iterative multiple objective programming approach finds preferred joint solutions in a
Native American tribal forestry case where marketable outputs are managed in the context of traditional culturally based forest
values. Without a priori specification of traditional tribal cultural values, conducting a series of feedback processes does
appear to identify more preferable solutions than other types of multiple-objective models that do not use feedback. 相似文献
89.
90.
Kaneda T Sakaguchi R Shimizu K Urakawa N Nakajyo S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1039-1045
A high-K+, Na+-deficient (I-154 K+) solution induced contraction followed by gradual relaxation of the smooth muscles of the bovine trachea, while hyperosmotic addition of 65 mM KCl induced a large sustained contraction. Exposure of the muscle to the I-154 K+ solution induced an increase in the ratio of cellular water content and a sustained increase in oxidized flavoprotein fluorescence or reduced pyridine nucleotide fluorescence. The I-154 K+ solution also induced a sustained increase in [Ca2+]i level. Decreases in developed tension and increases in cellular water content were both prevented by the addition of sucrose or NaCl but not pyruvate. Substitution of KI for KCl in the I-154 K+ solution produced a greater inhibition of contraction, while substitution with K-propionate produced no inhibition of contraction. Moreover, decreases in developed tension and increases in cellular water content were both prevented by addition of 100 microM 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS), but not 10 microM bumetanide or 1 mM acetazolamide. In conclusion, I-154 K+ solution induced-relaxation in the bovine trachea may be due to swelling of smooth muscle cells and the mechanism of swelling is probably involved in DIDS-sensitive anion movement. 相似文献