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991.
In this study, waste lignocellulosic sawdust was converted to carboxymethylcellulose (CMC) by the combination process of an inorganic base (NaOH) and a weak acid (monochloroacetic acid, MCA). Optimum conditions for the pretreatment were studied on the basis of lignin and hemicellulose removal. NaOH and MCA concentration, reaction time, and operating temperature were the parameters studied to acquire the optimized conditions for the production of CMC. Degree of substitution (DS) and solubility were greatly influenced by the changes in the experimental conditions. DS increased on increasing the concentration of NaOH and MCA but the effect was more profound during the NaOH loading. A maximum DS of 0.5 was obtained on the treatment with 20 % NaOH and 20 % MCA concentration at 50 °C, 150 rpm for 4 h. 1.28 g CMC/g cellulose was obtained at the optimized set of conditions. Structural information of cellulose and CMC was obtained using IR spectroscopy and the surface morphology was studied using field emission scanning electron microscopy (FESEM). Carboxymethylcellulose showed lower crystallinity than the native cellulose extracted from sawdust which was studied using X-ray diffraction. 相似文献
992.
Hyun Sook Han Ji Young Kim Sung Min Kim Ho Sun Lim Chang Kyu Park 《Fibers and Polymers》2014,15(2):422-425
This study developed a system that automatically created individually customized patterns by combining the two methods of “automatic drafting by pattern formulae” and “grading”. The system reads four kinds of information: body measurements; basic size pattern; grading values of the pattern’s points; and an alteration rule. Using the files, the system automatically generated a grading pattern first, and then modified it according to the alteration rule to make individually customized patterns. The clothing produced from the customized pattern fit the subject better than the clothing produced from the grading method. 相似文献
993.
Estimation of flood risk index considering the regional flood characteristics: a case of South Korea
Jung Younghun Shin Yongchul Jang Chun Hwa Kum Donghyuk Kim Young Sug Lim Kyoung Jae Kim Hyun Bae Park Tae Sun Lee Seung Oh 《Paddy and Water Environment》2014,12(1):41-49
Global warming is increasing the variability of climate change and intensifying hydrologic cycle components including precipitation, infiltration, evapotranspiration, and runoff. These changes increase the chance of more severe and frequent natural conditions, and limit ecosystem function and human activities. Adaptation to climate change requires assessment of the potential disaster risk. The objectives of this study were to estimate the flood risk index (FRI) considering regional flood characteristics at the national level and to prioritize the factors affecting flood risk through principal component analysis. FRI was estimated based on the Delphi survey results from 50 water resources experts in South Korea. The potential risk analysis was conducted for 229 local governments in South Korea. The results showed that natural and social factors were more influential flood risk factors to South Korea than administrative and economic and facility factors. Specifically, natural, social, administrative and economic, and facility factors were, respectively, highest at Jindo-Gun in Jennam-Do, Gumi-Si in Kyongsanbuk-Do, Dong-Gu in Incheon-Si, and Suwon-Si, Kyonggi-Do. Overall, the highest FRI is shown in Anyang-Si, Kyongggi-Do. The spatial distribution of the FRI was high in the southeastern coastal region and basins of the two biggest rivers in South Korea, and normalized flood frequency followed spatial patterns similar to FRIs. This study provided information on the relative flood risk index among administrative units for investment prioritization in flood risk management. In this regard, the suggested FRI is expected to significantly contribute to methodical and economic improvements in budget allocations for flood risk management. 相似文献
994.
Sung-Suk Suh Jinik Hwang Mirye Park Hyo Hyun Seo Hyoung-Shik Kim Jeong Hun Lee Sang Hyun Moh Taek-Kyun Lee 《Marine drugs》2014,12(10):5174-5187
Certain photosynthetic marine organisms have evolved mechanisms to counteract UV-radiation by synthesizing UV-absorbing compounds, such as mycosporine-like amino acids (MAAs). In this study, MAAs were separated from the extracts of marine green alga Chlamydomonas hedleyi using HPLC and were identified as porphyra-334, shinorine, and mycosporine-glycine (mycosporine-Gly), based on their retention times and maximum absorption wavelengths. Furthermore, their structures were confirmed by triple quadrupole MS/MS. Their roles as UV-absorbing compounds were investigated in the human fibroblast cell line HaCaT by analyzing the expression levels of genes associated with antioxidant activity, inflammation, and skin aging in response to UV irradiation. The mycosporine-Gly extract, but not the other MAAs, had strong antioxidant activity in the 2,2-diphenyl-1-picryhydrazyl (DPPH) assay. Furthermore, treatment with mycosporine-Gly resulted in a significant decrease in COX-2 mRNA levels, which are typically increased in response to inflammation in the skin, in a concentration-dependent manner. Additionally, in the presence of MAAs, the UV-suppressed genes, procollagen C proteinase enhancer (PCOLCE) and elastin, which are related to skin aging, had increased expression levels equal to those in UV-mock treated cells. Interestingly, the increased expression of involucrin after UV exposure was suppressed by treatment with the MAAs mycosporine-Gly and shinorine, but not porphyra-334. This is the first report investigating the biological activities of microalgae-derived MAAs in human cells. 相似文献
995.
Jae-hong Choi Mi-hyeon Kim Joon-soo Park Jeong-min Jeon Dae-ok Kim A. D. Towns 《Fibers and Polymers》2007,8(1):37-42
In Part 1 of this study, the dyeability, color shade, wash, light fastness and compatibility of homogeneous disperse dyes
on PLA fabric and PET fabric were reported. The present paper (Part 2) focuses on the application of commercial disperse dyes
to PLA fabric. Specific areas of investigation are the coloration properties of dyes originally intended for the production
of high lightfastness polyester fabrics or for application to cellulose diacetate. The compatibility of the eight members
of the dye set was investigated. In terms of lightfastness, the ratings were higher than that of conventional disperse dyes.
In addition, the use of dye combinations to achieve synergistic uptake on PLA was explored leading to the pronounced synergism
with a mixture of CI Disperse Blue 374 and 284. 相似文献
996.
Kang MR Kim HM Kang JS Lee K Lee SD Hyun DH In MJ Park SK Kim DC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):101-106
This study was performed to elucidate the anticancer mechanism of a lipid-soluble ginseng extract (LSGE) by analyzing induction
of apoptosis and arrest of cell cycle progression using the NCI-H460 human lung cancer cell line. Proliferation of NCI-H460
cells was potently inhibited by LSGE in a dose-dependent manner. The cell cycle arrest at the G0/G1 phase in NCI-H460 cells
was induced by LSGE. The percentage of G0/G1 phase cells significantly increased, while that of S phase cells decreased after
treatment with LSGE. The expression levels of cyclin-dependent kinase2 (CDK2), CDK4, CDK6, cyclin D3 and cyclin E related
to G0/G1 cells progression were also altered by LSGE. In addition, LSGE-induced cell death occurred through apoptosis, which
was accompanied by increasing the activity of caspases including caspase-8, caspase-9 and caspase-3. Consistent with enhancement
of caspase activity, LSGE increased protein levels of cleaved caspase-3, caspase-8, caspase-9, and poly-ADP-ribose polymerase
(PARP). These apoptotic effects of LSGE were inhibited by the pan-caspase inhibitor Z-VAD-fmk. These findings indicate that
LSGE inhibits NCI-H460 human lung cancer cell growth by cell cycle arrest at the G0/G1 phase and induction of caspase-mediated
apoptosis. 相似文献
997.
Planning interventions have been applied to improve the well‐being, hereafter happiness, of residents. The happiness in shrinking cities, in particular, becomes more critical since urban decline tends to induce an unequal and uneven distribution of care under a limited budget and human resources. Using geo‐tagged Twitter, census, and geospatial data on Detroit, Michigan, which is one of the well‐known shrinking cities in the U.S., the spatial distribution of sentiments, topics of tweets appeared, and the association between neighborhood conditions and the level of happiness were examined. The outcomes indicate that people in Detroit are posting happy tweets more than negative tweets. The downtown area holds both positive and negative hotspots, which are clustered around sports arenas and bars, respectively. Neighborhoods with young and well‐educated residents, situated close to amenities (i.e., recreation facilities, colleges, and commercial areas), and less crime tend to be happier. The use of SNS data could serve as a meaningful social listening tool to reconcile the declining urban vitality of neighborhoods since people interact with those spaces. Negative sentiments are attached to specific neighborhoods with certain conditions so that regeneration efforts should take place in neighborhoods with a higher priority. 相似文献
998.
Colonization of Carya cordiformis sapwood by Ceratocystis smalleyi and subsequent host defence responses following artificial inoculation were investigated using anatomical and histological techniques. Hyphae of C. smalleyi were observed in all sapwood xylem features confirming the ability of the pathogen to invade and colonize the xylem tissues of the host species. The fungus was isolated from within and at the margins of discoloured sapwood areas at 2 and 12 months after inoculation. General host defence responses that included vessel occlusion with gels or tyloses, lipid accumulation, and production of phenolic compounds were observed in xylem tissues of inoculated C. cordiformis stems. Pectic substances, lipids, and to a rare extent, phenolic compounds were detected in vascular gels. The lipid‐rich barriers observed likely prevent lateral expansion of the fungus in the sapwood. Furthermore, lack of fungus sporulation within vessels may restrict axial spread of the fungus. C. smalleyi appears to be a limited vascular wilt pathogen of bitternut hickory based on these observations and previously reported sap flow reduction correlated with multiple infections in artificially inoculated trees. 相似文献
999.
J.M. Kim B.D. Choi B.C. Kim S.S. Park & K.C. Hong 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(2):134-141
Pig breeding is aimed at improving lean meat production ability as well as meat quality, and muscle fibre characteristics may be important for enhancing these traits. Therefore, new molecular markers have been demanded for selecting lean meat production ability and meat quality in live animals. Myogenin belongs to the MyoD gene family, and is a candidate gene responsible for muscle fibre characteristics. We identified a new single nucleotide polymorphism (SNP) site in the 5' upstream region of the myogenin gene (nucleotides C and T). A total of 252 pigs of three breeds were genotyped by polymerase chain reaction–restriction fragment length polymorphism using BspCNI . Additionally, they were genotyped for the previously detected Msp I site in the 3'-flanking region (alleles A and B). The CCBB diplotype had the highest frequency over breeds, followed by TCBB and CCAB. The other diplotypes were not found in studied pigs. Association analysis performed for the markers found that the TCBB diplotype has desirable effects on the total number of fibres (p < 0.002), fibre cross-sectional area (p < 0.06), and loin eye area (p < 0.001) than the other diplotypes. Moreover, the diplotype had the highest muscle pH value (p < 0.07) and all meat quality traits were near the upper limit of the normal range as a reddish pink, firm and non-exudative (RFN) pork. Therefore, we suggest that selection for the myogenin diplotypes could improve total muscle fibre number, size and lean meat production ability with good meat quality. 相似文献
1000.
SR Lee J-W Kim BS Kim D-H Yoo YS Park T-H Lee J-H Ha B-H Hyun ZY Ryoo 《Reproduction in domestic animals》2009,44(5):740-744
In this study, we investigated parthenogenetic induction of canine oocytes by electrical stimulation following Ca-EDTA treatment. Oocyte maturation, parthenogenetic development, and cleavage rate in canine after various electrical stimulations (1.5, 1.8, 2.1 kV/cm) for 50 μs with single DC pulse following 1 mM Ca-EDTA treatment were investigated. In oocyte activated electrically at the voltage of 1.5 kV/cm after 1 mM Ca-EDTA treatment, the rate of pronucleus and two-cell was 4.1% and 2.7%, respectively. Although electrical stimulation could parthenogenetically induce immature oocyte to cleavage stage, degeneration rate in all experimental groups was more than 60%. This means that electrical stimulation after Ca-EDTA treatment could cause canine oocytes to be degenerated. However, two-cell in canine oocyte by parthenogenesis was for the first time induced. Therefore, we suggested that electrical stimulation for canine oocytes could induce parthenogenetically early embryonic cleavage. This result can be used as a basic data for parthenogenesis study in canine. Also, to perform more developed embryonic development, further study to parthenogenesis in canine need to be developed. 相似文献