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81.
Wook Kang Chun-Won Kang Woo Yang Chung Chang-Deuk Eom Hwanmyeong Yeo 《Journal of Wood Science》2008,54(5):343-348
This study was undertaken to estimate the effect of openings between cell walls on combined bound water and water vapor diffusion
in wood. Using a newly developed model, the radial and tangential moisture diffusion coefficients can be predicted depending
on the opening area. The new model explicitly involves a term for water vapor diffusion through the openings, as well as a
term for the combined diffusion of bound water and water vapor. A classical model developed by Stamm and Choong had higher
longitudinal moisture diffusion coefficients than that in the parallel model at higher moisture content, which is inconsistent
with the Wiener bound rule. The new model suggested in this article is useful for analyzing the experimental results and understanding
the variability of the diffusion coefficients. 相似文献
82.
Renilla luciferase (RLUC) is a popular reporter enzyme for gene expression and biosensor applications, but it is an unstable enzyme whose catalytic mechanism remains to be elucidated. We titrated that one RLUC molecule can turn over about one hundred molecules of coelenterazine substrate. Mutagenesis of active site residue Pro220 extended the half-life of photon emission, yielding brighter luminescence in E. coli. Random mutagenesis uncovered two new mutations that stabilized and increased photon emission in vivo and in vitro, while ameliorating substrate inhibition. Further amended with a previously identified mutation, a new triple mutant showed a threefold improved kcat, as well as elevated luminescence in Arabidopsis. This advances the utility of RLUC as a reporter protein, biosensor, or resonance energy donor. 相似文献
83.
Jeong Hyo Lee Jeong‐Woong Park Eun Sol Seo Hoy‐Ung Kim Seo Woo Kim Ji Seon Han Hyun Sik Jun Sung‐Jo Kim Tae Sub Park Byung‐Chul Park 《Animal Science Journal》2019,90(7):903-912
The value‐added products in livestock industry is one of the key issues in order to maximize the revenue and to create a new business model. Numerous studies have suggested application of herbal plants as feed additives to increase health, productivity, and/or high‐quality product in livestock. In this study, the first experiment was designed to develop in vitro evaluation system by using primary chicken myoblast (pCM) cells isolated from pectoralis major of 10‐day‐old male embryos. Subsequently, to evaluate effects of Korean Danggui Angelica gigas Nakai (AGN), we optimized the concentration of AGN root extract for treatment of primary pCM cells. After the treatment of AGN root extract, we compared proliferation and differentiation capacity, and also examined the gene expression. In the second experiment, the next generation sequencing analysis was performed to compare the different patterns of the global gene expression in pCM cells treated with AGN extract. Three up‐regulated (pancreas beta cells, fatty acid metabolism and glycolysis) and one down‐regulated (adipogenesis) gene sets were characterized suggesting that the AGN extract affected the metabolic pathways for the utilization of fat and glucose in chicken muscle cells. Furthermore, we validated the expression patterns of the up‐regulated genes (GCLC, PTPN6, ISL1, SLC25A13, TGFBI, and YWHAH) in the AGN‐treated pCM cells by quantitative RT‐PCR. These results demonstrated that the treatment of AGN extract decreased proliferation and differentiation of pCM cells, and affected the metabolic pathways of glucose and fatty acids. Moreover, AGN extract derived from byproducts such as stem and leaf also showed the reduced proliferation patterns on AGN‐treated pCM cells. Taken together, pCM cell‐based in vitro assay system could be primarily and efficiently applied for evaluating the biofunctional efficacy of various feed additive candidates. 相似文献
84.
为探求害虫防治时期,和发生数量方面的防治标准,以三化螟(Tryporyza incertulas (Wlk.)、二化螟(Chilo suppressalis Wlk.)和稻瘿蚊(Pachydiplosis oryzae Wood-mason)三种水稻钻心害虫为材料,探討钻心类害虫防治标准的規律,提出如下意見: 1.关于防治时期的标准,認为可将施药时虫态的发育进度百分率数字,换算为概率单位,在概率单位为4—6时,相当于15.87—84.13%时的害虫相对发生数量,占全世代总发生数量的68.268%,可見在該段短时間(一般約十数天)的虫数,代表了虫羣的大半数,可看作标准的盛发期,在此时間数列范围內,似可作为防治时期的标准。 2.关于发生数量的防治标准,以三化螟及稻瘿蚊为例进行討論:認为应以幼虫侵入作物后至老熟(或蛹化)期間,每虫所能造成的被害株数为基础,求出幼虫密度的防治标准,然后根据調查时的不同虫态,再伸算各該虫态的防治标准。本文列举了各虫态密度防治标准的計算公式,并以广州及南京两地的三化螟和广东信宜的稻瘿蚊为例,作出在各种具体条件下,虫口密度防治标准检索表。 相似文献
85.
86.
Woo SR Sotos J Hart AP Barletta RG Czuprynski CJ 《Veterinary immunology and immunopathology》2006,110(1-2):109-120
Bovine monocytes exhibited a greater ability to phagocytose Mycobacterium avium subsp. paratuberculosis (i.e. greater percentage of infected cells, and more bacilli per infected cell), than did a bovine macrophage cell line (BoMac). Phagocytosis of M. paratuberculosis by monocytes, but not the cell line, was significantly enhanced by the addition of autologous serum. Following ingestion, the numbers of viable M. paratuberculosis cells in monocytes increased during the first 4 days and then declined between day 4 and day 8 after infection, as determined by a radiometric method. In contrast, BoMac cells were not permissive for bacillary multiplication; the numbers of M. paratuberculosis remained largely unchanged in the cell line during the 8 day incubation period. The numbers of microscopically visible acid-fast bacilli increased with time in monocytes but not in the macrophage cell line. These observations suggest that replication and inactivation of bacilli may both occur in monocytes. The differing abilities of bovine monocytes and the macrophage cell line to ingest and restrain the intracellular growth of M. paratuberculosis provide contrasting model systems for investigating how M. paratuberculosis enters and persists within its preferred niche, the mononuclear phagocyte. 相似文献
87.
母猪妊娠期和哺乳期的理想氨基酸平衡 总被引:1,自引:0,他引:1
1摘要 对于限饲条件下的妊娠母猪以及采食量有限的哺乳母猪来说,改善蛋白质利用效率很重要。母猪在妊娠后期维持胎儿和乳腺发育以及在哺乳期促进乳腺生长和产奶的能力不足,特别是在第一个哺乳期。进行一系列研究来测定这些营养需要量以及氨基酸的理想比率,包括:1)胎儿生长;2)妊娠期母猪乳腺生长;3)妊娠母猪母体组织增重;4)哺乳母猪的乳腺生长;5)哺乳期母猪母体组织增重。 相似文献
88.
Kang BJ Ryu HH Park SS Kim Y Woo HM Kim WH Kweon OK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(7):827-836
Adipose tissue-derived mesenchymal stem cells (Ad-MSCs) are a promising source of cells for bone tissue engineering. Matrigel is a basement membrane extract containing multiple extracellular components. This mixture may promote the osteogenic differentiation of MSCs and provide a more appropriate microenvironment for transplanted cells. Here, we investigated the effect of Matrigel on the osteogenic potential of Ad-MSCs. Canine Ad-MSCs were cultured in 2D and 3D matrices and implanted into subcutaneous pouches of dogs either with or without Matrigel. Culture mineralization, cell adhesion efficiency, cell proliferation, osteoid matrix production and alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase activities were quantified and compared. Ad-MSCs grown in 2D cultures with Matrigel showed higher levels of calcium deposition and ALP activity than those grown in the absence of Matrigel under osteogenic conditions. In 3D cultures, the cells cultivated with Matrigel showed greater attachment, proliferation and osteogenic differentiation than those grown without Matrigel. In vivo, Ad-MSCs implanted with Matrigel showed higher osteogenic potential than those without Matrigel. In conclusion, these data suggest that the use of Matrigel can increase the osteogenic potential of canine Ad-MSCs. 相似文献
89.
Woo SR Barletta RG Czuprynski CJ 《Comparative immunology, microbiology and infectious diseases》2009,32(5):365-377
Mycobacterium avium subsp. paratuberculosis is the etiologic agent of Johne's disease, a chronic intestinal infection in ruminants. Adenosine 5'-Triphosphate (ATP) has been reported to induce killing of several Mycobacterium species in human and murine macrophages. We investigated whether ATP secreted from M. avium subsp. paratuberculosis-infected bovine monocytes affects intracellular survival of the bacilli. Bovine monocytes constitutively secreted ATP during an 8-day incubation period in vitro; however, M. avium subsp. paratuberculosis infection did not enhance ATP release. Removal of extracellular ATP by the addition of apyrase increased the viability of infected monocytes, but surprisingly decreased the number of viable intracellular bacilli. In contrast to previous reports, addition of extracellular ATP (1mM) increased intracellular survival of M. avium subsp. paratuberculosis in bovine monocytes. Neither apyrase nor ATP altered production of reactive oxygen intermediates (ROI) or reactive nitrogen intermediates (RNI) by bovine monocytes. These results suggest that ATP release from infected bovine monocytes improves, rather than decreases, the intracellular survival of M. avium subsp. paratuberculosis. 相似文献
90.