全文获取类型
收费全文 | 534篇 |
免费 | 31篇 |
专业分类
林业 | 29篇 |
农学 | 21篇 |
基础科学 | 1篇 |
77篇 | |
综合类 | 37篇 |
农作物 | 136篇 |
水产渔业 | 70篇 |
畜牧兽医 | 161篇 |
园艺 | 7篇 |
植物保护 | 26篇 |
出版年
2023年 | 1篇 |
2022年 | 9篇 |
2021年 | 24篇 |
2020年 | 12篇 |
2019年 | 14篇 |
2018年 | 17篇 |
2017年 | 10篇 |
2016年 | 24篇 |
2015年 | 20篇 |
2014年 | 28篇 |
2013年 | 30篇 |
2012年 | 47篇 |
2011年 | 57篇 |
2010年 | 28篇 |
2009年 | 26篇 |
2008年 | 32篇 |
2007年 | 37篇 |
2006年 | 28篇 |
2005年 | 26篇 |
2004年 | 21篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 8篇 |
1999年 | 6篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有565条查询结果,搜索用时 328 毫秒
51.
Protective effect of anthocyanins from black soybean seed coats on UVB-induced apoptotic cell death in vitro and in vivo 总被引:1,自引:0,他引:1
Tsoyi K Park HB Kim YM Chung JI Shin SC Shim HJ Lee WS Seo HG Lee JH Chang KC Kim HJ 《Journal of agricultural and food chemistry》2008,56(22):10600-10605
UVB radiation proves to be one of the most relevant environmental risks because of its hazardous effects, such as premature skin aging and especially skin photocarcinogenesis. Anthocyanins, water-soluble pigments present in plants, are known to be powerful antioxidants that help protect plants from UV damage. In this study, we aimed at investigating the protective effect of anthocyanins from black soybean [Glycine max (L.) Merr] seed coats on UVB-induced apoptosis, and furthermore, we investigated the molecular mechanism responsible for regulation of apoptosis in vitro and in vivo. Pretreatment with anthocyanins reduced UVB-induced reactive oxygen species levels and inhibited UVB-induced apoptotic cell death through the prevention of caspase-3 pathway activation and reduction of proapoptotic Bax protein levels. UVB irradiation induced apoptotic cell death, which was inhibited by topical application of anthocyanins in hairless mice. It is concluded that anthocyanins from the seed coat of black soybeans may be useful compounds to modulate UVB-induced photoaging. 相似文献
52.
Hwang IK Choi JH Li H Yoo KY Kim DW Lee CH Yi SS Seong JK Lee IS Yoon YS Won MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(9):965-969
Astrocytes perform neuron-supportive tasks, repair and scarring process in the central nervous system. In this study, we observed glial fibrillary acidic protein (GFAP), a marker for astrocytes, immunoreactivity in the dentate gyrus and hippocampus proper (CA1-3 region) of adult (2-3 years of age) and aged (10-12 years of age) dogs. In the adult group, GFAP immunoreactive astrocytes were distributed in all layers of the dentate gyrus and CA1-3 region, except in the stratum pyramidale of the CA1-3 region. In the aged group, GFAP immunoreactivity decreased markedly in the molecular layer of the dentate gyrus. However, GFAP immunoreactivity in the CA1-3 region increased in all layers, and the cytoplasm of GFAP immunoreactive astrocytes was hypertrophied. GFAP protein levels in the aged dentate gyrus decreased; however, GFAP levels in the CA1-3 region increased. These results suggest that the morphology of astrocytes and GFAP protein levels in the hippocampal dentate gyrus and CA1 region are changed, respectively, with age. 相似文献
53.
Lee CH Choi JH Chung DW Hwang IK Yoon YS Won MH Lee IS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(6):645-648
We compared the immunoreactivity and numbers of tyrosine hydroxylase (TH) immunoreactive neurons and neuropil in the paraventricular nucleus (PVN) of the hypothalamus between the seizure sensitive (SS) and seizure resistant (SR) gerbils. The distributional pattern of TH immunoreactivity was similar in both groups: TH immunoreactivity was seen mainly in magnocellular neurons of the PVN. However, total TH immunoreactivity in the neurons and neuropil in the SS gerbils was significantly lower than that in the SR gerbils. In addition, the number of TH immunoreactive neurons in the SS gerbils was also much lower than those in the SR gerbils. These results indicate that SS gerbils have a low TH immunoreactivity in the hypothalamic PVN compared with that in SR gerbils. 相似文献
54.
Effects of illite supplementation on in vitro and in vivo rumen fermentation,microbial population and methane emission of Hanwoo steers fed high concentrate diets 下载免费PDF全文
Ashraf A. Biswas Sung‐Sill Lee Lovelia L. Mamuad Seon‐Ho Kim Yeon‐Jae Choi Chanhee Lee Kichoon Lee Gui‐Seck Bae Sang‐Suk Lee 《Animal Science Journal》2018,89(1):114-121
This study was conducted to evaluate the effects of feeding supplemental illite to Hanwoo steers on methane (CH4) emission and rumen fermentation parameters. An in vitro ruminal fermentation technique was conducted using a commercial concentrate as substrate and illite was added at different concentrations as treatments: 0%, 0.5%, 1.0%, and 2.0% illite. Total volatile fatty acids (VFA) were different (P < 0.05) at 24 h of incubation where the highest total VFA was observed at 1.0% of illite. Conversely, lowest CH4 production (P < 0.01) was found at 1.0% of illite. In the in vivo experiment, two diets were provided, without illite and with addition of 1% illite. An automated head chamber (GreenFeed) system was used to measure enteric CH4 production. Cattle received illite supplemented feed increased (P < 0.05) total VFA concentrations in the rumen compared with those fed control. Feeding illite numerically decreased CH4 production (g/day) and yield (g/kg dry matter intake). Rumen microbial population analysis indicated that the population of total bacteria, protozoa and methanogens were lower (P < 0.05) for illite compared with the control. Accordingly, overall results suggested that feeding a diet supplemented with 1% illite can have positive effects on feed fermentation in the rumen and enteric CH4 mitigation in beef cattle. 相似文献
55.
Sung Hwoan Cho 《Journal of the World Aquaculture Society》2011,42(1):90-95
The effect on growth and body composition of various dietary additives with putative growth or health‐enhancing properties were determined in juvenile olive flounder (25 g initial weight). Nine experimental diets were prepared to contain one of the following additives: control (Con) with no additive, Opuntia ficus‐indica ver. saboten (OF), propolis (PP), lactic acid bacteria (LA), γ‐poly‐glutamic acid (PG), onion extract (OE), organic sulfur (OS), Biostone® (BS), and fig extract (FE). Fishmeal, dehulled soybean meal, and corn gluten were used as the protein source of the experimental diets. Wheat flour and soybean oil were used as the carbohydrate and lipid sources, respectively. Dietary additives were included in each experimental diet at 1% at the expense of wheat flour except for the FE (aqueous), which was substituted at 1% of the amount of water added to the diet. Fish were hand‐fed to satiation twice a day for 6 d/wk for 6 wk. Weight gain of fish fed the OE diet was higher than that of fish fed with the PP diet. Chemical composition of fish was not different among the experimental diets. OE was the most effective dietary additive to improve performance of olive flounder among additives used in this study. 相似文献
56.
Jin‐Ha Yu Jung Jo Han Kwon Sam Park Kwan Ha Park Sung Woo Park 《Aquaculture Research》2009,41(1):19-26
Mass mortality of Korean catfish, Silurus asotus, occurred in a culture farm situated in Jeollabukdo Province, Korea. The cumulative mortality rates reached up to 5% of the total fish in the farm per day. In clinical signs, the affected fish showed abdominal distension, vent protrusion, enteritis, liver congestion and abscess‐like lesions in enlarged spleen and kidney. Histopathologically, in the liver, hepatocytes lost fat and underwent atrophy or necrosis. The spleen showed necrotized splenocytes and a haemorrhagic pulp. In the kidney, glomerular destruction, degeneration of renal tubular epithelial cell and haemorrhage were observed. However, necrotic muscular lesions were not observed. A pure bacterial isolate was obtained from the liver, spleen and kidney lesions of affected fish. Experimental infection of normal catfish with the isolate resulted in the development of clinical signs similar to those seen on the farm. The isolates were identified as Edwardsiella tarda through biochemical tests (99.4%) and analysis of bacterial genes (16S rDNA) sequences (98%). The bacteria possessed two virulent genes: sodB and katB genes. These results suggest that E. tarda can act as a pathogen of farmed catfish. This is the first report showing that E. tarda caused mortality in cultured Korean catfish. 相似文献
57.
The authentication of rice by imaging three sides (top, side, and front) of a rice kernel using two mirrors was attempted. Nine image characteristics (area, aspect ratio, minimum diameter, maximum diameter, perimeter, and red, green, and blue values) for each side of a rice kernel were measured. Japonica type rices were used for the study; a total of 89 rice samples were used: 40 samples harvested in Korea, 33 in America, 5 in Australia, and 11 in China. Image data collected from 105 kernels per rice sample were used as a calibration data set to develop a model for quadratic discriminant analysis. In overall pairwise trials, on average, 85.8–94.5% correct identification of the cultivated country was obtained, depending on the number of image characteristics used for the discriminant model. For the effective discrimination of the cultivated country, 13 image characteristics were selected. As a test sample set, 20 kernels per sample were used. A model for discriminant analysis with 13 image characteristics yielded an average of 95.0 and 97.5% accuracy for calibration and test sample set, respectively. 相似文献
58.
Sung Hwoan Cho 《Aquaculture Research》2010,41(10):e587-e593
The effect of dietary substitution of animal and/or plant protein sources for fishmeal on the growth and body composition of juvenile abalone was determined. Nine experimental diets in triplicate were prepared: Con, SM, PM, CM, SPM, MB, SM+CM, SM+SPM and CM+SPM diets. A 350 g kg?1 fishmeal was included in the Con diet, and the whole fishmeal was substituted with a 580 g kg?1 soybean meal (SM), 335 g kg?1 poultry meal (PM), 370 g kg?1 corn gluten meal (CM), 325 g kg?1 silkworm pupae meal dehydrated (SPM), 590 g kg?1 meat and bone meal (MB), the combined 290 g kg?1 soybean meal and 180 g kg?1 corn gluten meal (SM+CM), 290 g kg?1 soybean meal and 160 g kg?1 silkworm pupae meal dehydrated (SM+SPM) and 180 g kg?1 corn gluten meal and 170 g kg?1 silkworm pupae meal dehydrated (CM+SPM) diets respectively. All experimental diets were iso‐nitronic and iso‐lipidic. The survival of abalone fed with the SM and SM+SPM diets was higher than that of abalone fed with the CM, SPM, MB and CM+SPM diets. Weight gain of abalone fed with the SM+SPM diet was higher than that of abalone fed with all the other experimental diets, except for that of abalone fed with the SM+CM diet. The combined soybean meal and corn gluten meal (SM+CM) or silkworm pupae meal (SM+SPM) could be replaced with the whole fishmeal in the diet for abalone and improved its performance. 相似文献
59.
60.