全文获取类型
收费全文 | 216篇 |
免费 | 11篇 |
国内免费 | 20篇 |
专业分类
林业 | 50篇 |
农学 | 20篇 |
基础科学 | 5篇 |
31篇 | |
综合类 | 89篇 |
农作物 | 14篇 |
水产渔业 | 7篇 |
畜牧兽医 | 14篇 |
园艺 | 5篇 |
植物保护 | 12篇 |
出版年
2024年 | 2篇 |
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 10篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 9篇 |
2013年 | 18篇 |
2012年 | 11篇 |
2011年 | 25篇 |
2010年 | 16篇 |
2009年 | 15篇 |
2008年 | 17篇 |
2007年 | 13篇 |
2006年 | 19篇 |
2005年 | 5篇 |
2004年 | 6篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1995年 | 4篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有247条查询结果,搜索用时 183 毫秒
81.
Richard R. Stange Jr Rocco Alessandro T. Greg Mc Collum Richard T. Mayer 《Physiological and Molecular Plant Pathology》2002,60(6):283
Pathological tissues from a variety of plants turn red when treated with the histochemical reagent phloroglucinol (PG)–HCl. This induced PG–HCl reacting material has been termed both wound gum and, more recently, induced lignin or lignin-like material. We are exploring alternative approaches to better identify this induced material. In this report, we describe methods for purifying the PG–HCl reactive material from solvent-washed tissue preparations and measuring the amount of p -coumaryl aldehyde released from the purified material by boiling in water. Acorn squash fruit wall tissue was sliced, sprayed with pectinase to elicit the formation of PG–HCl reactive material and incubated up to 72 h at 27°C. Sampled tissue was washed extensively with water and organic solvents. Insoluble residues were treated with cell wall degrading enzymes to remove cell wall materials, and dimethyl sulfoxide was used to dissolve starch. Yields of residual material increased from 7.5% in the time zero samples to 29.7% after 72 h. Refluxing the purified material in water released <6 μ g p -coumaryl aldehyde g−1 from preparations of tissue at time zero and 8100 μ g p -coumaryl aldehyde g−1 from samples incubated for 48 h. These results suggest that the function of the material is to sequester phytoalexins, but are not consistent with the material being lignin. Published by Elsevier Science Ltd. 相似文献
82.
83.
以新疆果树为试材,研究了山桃、蟠桃、桃杏、杏、巴旦杏、李子、李子幼林、水蜜桃、黄果山楂、新疆梨、石榴共11个果树原胶的出胶率和出胶量.结果表明:山桃、蟠桃、巴旦杏、桃杏和杏的出胶率和出胶量较大,高达90%的树木都出胶,且单株出胶量多在40~50 g;李子和水蜜桃的出胶率则较小,一般在25%,单株出胶量1~3 g;黄果山楂、新疆梨和石榴未发现出胶. 相似文献
84.
Hongyan Han Sayaka Yamanaka Takamitsu Tsukahara Yoshio Hotta Tokuji Takagi Hajime Kumagai 《Animal Science Journal》2021,92(1):e13651
Gum arabic (GA) has potential rumen modifier functions. This is the first study to investigate the in vitro ruminal fermentation characteristics of GA. Rumen fluid was collected from ruminal fistulated wethers; rolled barley and ryegrass straw were used as substrates for concentrate and forage conditions, respectively. Besides incubating with the substrates alone (control), GA or potato starch (PS) was added at 0.2%, 1.0%, and 2.0% along with substrates. Under the concentrate substrate condition, GA treatments showed higher total gas production in 24-h incubation, but lower methane production in 24- and 48-h incubation compared with PS treatments (p < 0.05). The 1.0% and 2.0% GA and 0.2% and 1.0% PS treatments showed higher dry matter and neutral detergent fiber digestibility and lower NH3-N, and higher short chain fatty acid concentrations compared with the control at 24-h incubation (p < 0.05). The GA treatments also showed a lower acetate/propionate ratio than PS treatments at 48-h incubation (p < 0.01). Under the forage substrate condition, the treatment effects were not significant, except for a higher proportion of propionate with GA than with PS at 24 and 48 h of incubations. We thus concluded that GA supplement may exert potential rumen modifier effects particularly under concentrate feeding condition. 相似文献
85.
仙草为中国传统的药用植物。探讨了以淀粉和仙草叶胶制备可食膜的可行性。未来将进一步探讨脱色仙草叶胶添加树薯淀粉可食膜微结构的变化。 相似文献
86.
87.
黄原胶溶液流变特性及应用研究进展 总被引:1,自引:0,他引:1
综述了黄原胶溶液的流变特性,以及黄原胶溶液的流变特性在食品工业及化学工业中的应用;重点论述了黄原胶作为悬浮剂、乳化剂、稳定剂、增稠剂等在食品工业和日用化学工业中的应用,并指出了黄原胶今后研究的发展方向. 相似文献
88.
89.
1995~2002年中国脂松香质量调查研究与统计分析 总被引:8,自引:3,他引:8
从各种不同渠道详细调查了1995年至2002年中国脂松香的质量状况,对调查结果进行了统计分析,并将调查结果与脂松香国家标准(GB/T8145-1987)的各项主要技术指标进行了相应的对比研究,结果表明,单就技术指标的统计平均结果而言,各个级别的脂松香质量均优于目前的国家标准要求,而且仍然具有国际领先水平,但是,“混合松香”等质量问题必须引起各方面的足够重视,根据中国采脂树种和客户实际需求的不断变化,按照不同树种或不同用途分别制定分类松香标准或专用松香标准将是未来质量要求的发展趋势。 相似文献
90.