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131.
We investigated an improved method for the separation of high-purified lutein from a commercially available spray-dried Chlorella powder (CP) using fine grinding by jet mill and flash column chromatography on a silica gel. Saponification and extraction of lutein were enhanced 2.3-2.9-fold in jet mill-treated CP (mean particle size, 20 microm) as compared to untreated CP (mean particle size, 67 microm). The carotenoid extract was dissolved in ether-hexane (1:1 v/v) and subjected to flash column chromatography on silica gel. A mixture of alpha- and beta-carotene was eluted with hexane, followed by elution with hexane-acetone-chloroform (7:2:1 v/v). Lutein (dark-orange band) was collected after the elution of an unknown colorless compound (detected based on UV absorbance). The purity of lutein in this fraction was over 99%, and the yield was 60%. The present study provides key information for obtaining highly purified lutein using flash column chromatography on a silica gel. 相似文献
132.
Sittinee KULPRASERTSRI Keisuke AOSHIMA Atsushi KOBAYASHI Takashi KIMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):734
Duck Tembusu virus (DTMUV), a neurotropic flavivirus, is a causative agent of severe neurological diseases in different birds. No approved vaccines or antiviral therapeutic treatments are available to date. The poultry industry experiences significant economic losses due to DTMUV infections. Minocycline is a second-generation semi-synthetic tetracycline analogue that is commonly used as an antimicrobial treatment. Experimental studies have indicated the successful protective effects of minocycline against neuronal cell death from neurodegenerative diseases and viral encephalitis. The aim of this study was to investigate the effects of minocycline on DTMUV infection in neurons. Primary duck neurons were treated with minocycline, which exhibited neuroprotective effects via anti-apoptotic function rather than through viral replication inhibition. Minocycline might serve as a potential effective drug in DTMUV infection. 相似文献
133.
Okita K Nakagawa M Hyenjong H Ichisaka T Yamanaka S 《Science (New York, N.Y.)》2008,322(5903):949-953
Induced pluripotent stem (iPS) cells have been generated from mouse and human somatic cells by introducing Oct3/4 and Sox2 with either Klf4 and c-Myc or Nanog and Lin28 using retroviruses or lentiviruses. Patient-specific iPS cells could be useful in drug discovery and regenerative medicine. However, viral integration into the host genome increases the risk of tumorigenicity. Here, we report the generation of mouse iPS cells without viral vectors. Repeated transfection of two expression plasmids, one containing the complementary DNAs (cDNAs) of Oct3/4, Sox2, and Klf4 and the other containing the c-Myc cDNA, into mouse embryonic fibroblasts resulted in iPS cells without evidence of plasmid integration, which produced teratomas when transplanted into mice and contributed to adult chimeras. The production of virus-free iPS cells, albeit from embryonic fibroblasts, addresses a critical safety concern for potential use of iPS cells in regenerative medicine. 相似文献
134.
Kubota Kenji Tsukahara Narutoshi Hoshino Keisuke Ikeda Kentaro Sakai Hiroshi Toriyama Kimihiko 《Journal of General Plant Pathology》2022,88(5):300-308
Journal of General Plant Pathology - Variable domain of heavy chain of heavy-chain (VHH) antibodies (Abs) have been widely applied for the detection and therapeutics of viral pathogens. Here, we... 相似文献
135.
Severe wilt and blight of entire plants of yacon (Smallanthus sonchifolius) grafts on sunflower (Helianthus annuus) were found in greenhouses in Kagawa Prefecture in the southwest region of Japan from April to May between 1997 and 1999. A mitosporic fungus, isolated repeatedly from the diseased plants and identified as Botrytis cinerea, was demonstrated to be virulent to both yacon and sunflower. The new disease on yacon was named gray mold of yacon. The disease on sunflower, gray mold of sunflower, is new to Japan. 相似文献
136.
A severe rot of postharvest fruits of sweet pepper, a variety of Capsicum annuum, was found in Kagawa Prefecture in southwestern Japan in August 1999. A fungus, isolated repeatedly from the diseased fruits
and identified as Stemphylium lycopersici, was demonstrated to be pathogenic to fruits of sweet pepper. The disease was new to Japan, and the fungus was added to the
pathogens causing fruit rot of C. annuum. 相似文献
137.
Megumi Kuroiwa Keisuke Koba Kazuo Isobe Ryunosuke Tateno Asami Nakanishi Yoshiyuki Inagaki Hiroto Toda Shigeto Otsuka Keishi Senoo Yuichi Suwa Muneoki Yoh Rieko Urakawa Hideaki Shibata 《Journal of Forest Research》2011,16(5):363-373
Measurements of gross NH 4 + and NO 3 ? production in forest soils were conducted using the 15N pool dilution method. Mineral topsoils (0?C10?cm depth) were collected from four forests from northern to southern Japan with a natural climate gradient to elucidate the mechanisms regulating gross nitrification rates in forest soils. Additionally, we attempted to evaluate the relative importance of heterotrophic nitrification in gross total nitrification using acetylene as a specific inhibitor of autotrophic nitrification. Distinct differences were found among sites in the gross rates of NH 4 + production (3.1?C11.4?mg?N?kg?1?day?1) and gross total nitrification (0.0?C6.1?mg?N?kg?1?day?1). The rates of gross heterotrophic nitrification were low in this study, indicating that heterotrophic nitrification is of minor importance in most forest mineral topsoils in Japan. Significant relations were found between gross autotrophic nitrification and gross NH 4 + production, soil N, and soil C concentrations, but none was found between gross autotrophic nitrification and soil pH. We determined the critical value of the gross NH 4 + production rates for gross autotrophic nitrification under which no gross autotrophic nitrification occurred, as well as the critical soil C/N ratio above which gross autotrophic nitrification ceased. Results show that tight coupling of production and consumption of NH 4 + prevents autotrophic nitrifiers from utilizing NH 4 + as long as NH 4 + availability is low. 相似文献
138.
Nitrogen compounds generated by anthropogenic combustion deposits in forest watersheds and induce nitrogen saturation of the area. Because excess nitrogen is derived from atmospheric deposition, this action is expected to uniformly affect a wide area of forest soils. Geographically, heterogeneous nitrate concentration of stream water within a small area has been attributed to the tree type, geological setting and tree cut. In this article, we hypothesized that the effect of the atmospheric nitrogen deposition in the forest watershed may vary within a small area, and that such variation is induced by the degree of air mass containing a high concentration of nitrogen deposition of combustion origin. We measured major ion concentrations, including nitrate, nitrite oxygen and nitrogen stable isotope of nitrate sampled at 24 water streams in the Chichibu region, which is 50?C100 km from the Tokyo metropolitan area. The nitrate concentration showed a wide range (25.6?C237 ??mol L?1) within 300 km2, which was explained sufficiently by the air mass advection path and its contact with the mountain??s surface. The nitrate concentration showed a significant positive correlation with chloride (r?=?0.73; p?<?0.001). As chloride originates outside of the Chichibu region, the positive correlation between two ions showed that the nitrate concentration of the stream water was affected by the nitrogen compound from the Tokyo Metropolitan area as a form of atmospheric deposition. Between the nitrate concentration and the stable isotope ratio of oxygen of nitrate, there was a positive correlation until nitrate concentration of 100 ??mol L?1. When the nitrate is over 100 ??mol L?1, ??18O shows a stable value of ca. 5.7??. This indicates that the nitrification proceeds when the nitrate concentration was low to middle, but the reaction slowed when the nitrate concentration became high. Oxygen stable isotope of nitrate along with a set of nitrate concentrations can be used as a good indicator of nitrogen saturation. 相似文献
139.
Yousuke NANIWA Keisuke NAKATSUKASA Shohei SETSUDA Shinya OISHI Nobutaka FUJII Fuko MATSUDA Yoshihisa UENOYAMA Hiroko TSUKAMURA Kei-ichiro MAEDA Satoshi OHKURA 《The Journal of reproduction and development》2013,59(6):588-594
Kisspeptin is a key molecule that stimulates gonadotropin secretion via release of
gonadotropin-releasing hormone (GnRH). In the present study, our aim was to
investigate whether kisspeptin has stimulatory effects on follicular development via
GnRH/gonadotropin secretion in cows. Japanese Black beef cows were intravenously
injected with full-length bovine kisspeptin [Kp-53 (0.2 or 2 nmol/kg)] or vehicle 5
days after they exhibited standing estrus (Day 0). In cows injected with Kp-53 at 2
nmol/kg, the follicular sizes of the first dominant follicles increased on Day 6 and
thereafter. Ovulation of the first dominant follicle occurred in 1 out of 4 cows
treated with Kp-53 at 2 nmol/kg. Injection of Kp-53 at 2 nmol/kg increased the
concentration of plasma luteinizing hormone (LH) but not follicle-stimulating
hormone, over a 4-h period following injection in all cows. The present study
suggests that administration of full-length kisspeptin causes LH secretion, which is
sustained for a few hours, and it is capable of stimulating follicular development
and/or ovulation. 相似文献
140.
Keisuke Suzuki Yasuhiro Kishioka Jun‐ichi Wakamatsu Takanori Nishimura 《Animal Science Journal》2013,84(9):669-674
Decorin, a small leucine‐rich proteoglycan, plays an important role in cellular activities through modification of growth factors. It also acts as a signaling molecule to non‐muscle cells through epidermal growth factor receptor or insulin‐like growth factor I receptor (IGF‐IR). However, it is unclear if decorin acts as a signaling molecule to myogenic cells. In this study, we investigated the effect of decorin on the differentiation of myoblasts and the signaling via IGF‐IR to myogenic cells. C2C12 myoblasts cultured in media containing decorin for 72 h showed more extensive formation of multinucleated myotubes than control cells cultured in the same media without decorin. The protein expressions of myogenin and myosin heavy chian were higher in decorn‐treated cells than in control cells. These results suggest that decorin enhances the differentiation of myoblasts. Western blot analysis and immunocytochemistry showed that IGF‐IR was expressed in myoblasts and myotubes. Furthermore, Akt, which is downstream of IGF‐IR, was more phosphorylated in myoblasts cultured in media containing decorin than those in media without decorin. These results suggest that decorin activates Akt downstream of IGF‐IR and enhances the differentiation of myogenic cells. 相似文献