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301.
Yamato SAJIKI Satoru KONNAI Reiko NAGATA Satoko KAWAJI Hayato NAKAMURA Sotaro FUJISAWA Tomohiro OKAGAWA Naoya MAEKAWA Yukinari KATO Yasuhiko SUZUKI Shiro MURATA Yasuyuki MORI Kazuhiko OHASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):162
Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic enteritis of ruminants. Previous studies have shown that programmed death-ligand 1 (PD-L1) is associated with the disease progression, and PD-L1 blockade activates MAP-specific Th1 responses in vitro. Here, we performed anti-PD-L1 antibody administration using 2 MAP-infected cattle at the late subclinical stage of infection. After administration, bacterial shedding was reduced or maintained at a low level. Additionally, MAP-specific Th1 cytokine production was upregulated, and CD69 expression was increased in T cells. Collectively, the treatment has a potential as a novel control method against Johne’s disease. 相似文献
302.
Takashi IKEDA Makoto ASANO Masatsugu SUZUKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):846
There is a possibility that classical swine fever (CSF) virus outbreak has negative impacts on wild boar. To adequately manage native wild boar populations, wildlife managers need to gather the field data on wild boar and implement population management practices. We aimed to report the relative abundance index of wild boar before and after this outbreak. Our results showed that relative abundance index declined from 2017 (8.88 wild boars/100 trap days) to 2019 (2.03 wild boars/100 trap days), because of the negative impact of this virus and continuous culling programs. Although the eradication risk from the synergistic effect is low, wildlife managers need to consider the relationship between the trade-off between the risk of CSF and the conservation ecology risk of native species eradication. 相似文献
303.
Shoji Hashimoto Nobuaki Tanaka Tomonori Kume Natsuko Yoshifuji Norifumi Hotta Katsunori Tanaka Masakazu Suzuki 《Journal of Forest Research》2007,12(3):209-221
Soil CO2 production seasonality at a number of depths was investigated in a temperate forest in Japan and in a tropical montane forest
in Thailand. The CO2 production rates were evaluated by examining differences in the estimated soil CO2 flux at adjacent depths. The temperate forest had clear temperature seasonality and only slight rainfall seasonality, whereas
the tropical montane forest showed clear rainfall seasonality and only slight temperature seasonality. In the temperate forest,
the pattern of seasonal variation in soil respiration was similar at all depths, except the deepest (0.65 m–), and respiration
was greater in summer and less in winter. The contribution of the shallowest depth (around 0.1 m) was more than 50% of total
soil-surface CO2 flux all year round, and the annual mean contribution was about 75%. CO2 production mostly appeared to increase with temperature in shallower layers. In contrast, in the tropical forest, soil CO2 production seasonality appeared to differ with depth. The CO2 production rate in the shallowest layer was high during the rainy season and low during the dry season. Soil CO2 production at greater depths (0.4 and 0.5 m–) showed the opposite seasonality to that in the shallower layer (around 0.1 m).
As a result, the contribution from the shallow depth was greatest in the tropical forest during the rainy season (more than
90%), whereas it decreased during the dry season (about 50%). CO2 production appeared to be controlled by soil water at all depths, and the different ranges of water saturation seemed to
cause the difference in seasonality at each depth. Our results suggest the importance of considering the vertical distribution
of soil processes, particularly in areas where soil water is a dominant controller of soil respiration. 相似文献
304.
Tomonori Sonoki Yosuke Iimura Eiji Masai Shinya Kajita Yoshihiro Katayama 《Journal of Wood Science》2002,48(5):429-433
Sphingomonas paucimobilis SYK-6 produces unique and specific enzymes, such as-etherases,O-demethylases, and ring fission dioxygenases, for lignin degradation. Cleavage of arylglycerol--aryl ether linkage is the most important process in the lignin metabolic pathway ofS. paucimobilis SYK-6. We reported the genes (ligD, ligE, ligF) for enzymes that cleaved-aryl ether linkage of dimeric compounds in previous studies. In this study we synthesized the fluorescent high-molecular-weight lignin (UBE-DHP) by dehydrogenative polymerization. We investigated the-aryl ether cleavage ability of these enzymes produced in recombinantEscherichia coli. When UBE-DHP was incubated with LigF, 4-methylumbeliferone was released as a result of-aryl ether cleavage of O-methylumbelliferyl--hydroxypropiovanillone (compound III) incorporated in UBE-DHP. Here, we report that-etherase ofS. paucimobilis SYK-6 can be expressed inE. coli and is able to cleave the-aryl ether linkage in synthetic high-molecular-weight lignin. 相似文献
305.
Tse D Takeuchi T Kakeyama M Kajii Y Okuno H Tohyama C Bito H Morris RG 《Science (New York, N.Y.)》2011,333(6044):891-895
When new learning occurs against the background of established prior knowledge, relevant new information can be assimilated into a schema and thereby expand the knowledge base. An animal model of this important component of memory consolidation reveals that systems memory consolidation can be very fast. In experiments with rats, we found that the hippocampal-dependent learning of new paired associates is associated with a striking up-regulation of immediate early genes in the prelimbic region of the medial prefrontal cortex, and that pharmacological interventions targeted at that area can prevent both new learning and the recall of remotely and even recently consolidated information. These findings challenge the concept of distinct fast (hippocampal) and slow (cortical) learning systems, and shed new light on the neural mechanisms of memory assimilation into schemas. 相似文献
306.
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308.
Key message
Measuring between-tree variations in sap flux density rather than azimuthal variations should be prioritized for reliable stand transpiration estimates based on sap flux methods.Context
Stand transpiration (E) estimated using sap flux methods includes uncertainty induced by azimuthal variations and between-tree variations in sap flux density (F).Aims
This study examines whether or not measuring F for two or more azimuthal directions to cover azimuthal variations in F leads to more reliable E estimates. This examination was done under the assumption that azimuthal and between-tree variations in F are not systematic and when a limited number of sensors are available.Methods
We first non-dimensionalized the theoretical framework established by a previous study and developed a general hypothesis. We then validated the hypothesis quantitatively by numerical experiments.Results
The non-dimensionalized theory allowed us to hypothesize that measuring F for one azimuthal direction would reduce uncertainty in E estimates more effectively than measuring F for two or more azimuthal directions. Results of the numerical experiments were found to support this hypothesis.Conclusion
When the aforementioned assumptions are satisfied, allocating sensors to measure F for one azimuthal direction to cover between-tree variations in F always leads to more reliable E estimates.309.
Kango TATEMOTO Keita ISHIJIMA Yudai KURODA Milagros Virhuez MENDOZA Yusuke INOUE Eunsil PARK Hiroshi SHIMODA Yuko SATO Tadaki SUZUKI Kazuo SUZUKI Shigeru MORIKAWA Ken MAEDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(7):982
The present study investigated severe fever with thrombocytopenia syndrome virus (SFTSV) infection in raccoons in Wakayama Prefecture from 2007 to 2019. To perform surveillance, an enzyme-linked immunosorbent assay (ELISA) was established, and the sensitivity and specificity of the ELISA were 100% in comparison with a 50% focus-reduction neutralization assay. Using the established ELISA, we performed serosurveillance of SFTSV infection in 2,299 raccoons in Tanabe region, Wakayama Prefecture from 2007 to 2019. The first anti-SFTSV-positive raccoon was captured in October 2009. The seroprevalence of SFTSV infection was <10% between April 2009 and March 2013, 23.9% between April 2013 and March 2014, 37.5% between April, 2014 and March 2015, and over 50% from April 2015. Next, we performed detection of SFTSV genes in sera of raccoons captured in Wakayama Prefecture after April 2013. The results indicated that 2.4% of raccoons were positive for SFTSV genes and that the frequency of SFTSV infection among raccoons between January and March (0.7%) was lower than that between April and June (3.4%). In addition, virus genes were detected from many specimens, including sera and feces of two raccoons, and viral antigens were detected in lymphoid cells in lymphoid follicles in the colon by immunohistochemical staining. In conclusion, SFTSV had recently invaded the area and had rapidly spread among wild animals. The first patient in this area was reported in June 2014, indicating that raccoons are good sentinels for assessing the risk of SFTSV in humans. 相似文献