全文获取类型
收费全文 | 237篇 |
免费 | 26篇 |
国内免费 | 9篇 |
专业分类
林业 | 25篇 |
农学 | 9篇 |
基础科学 | 3篇 |
27篇 | |
综合类 | 46篇 |
农作物 | 28篇 |
水产渔业 | 56篇 |
畜牧兽医 | 57篇 |
园艺 | 9篇 |
植物保护 | 12篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 8篇 |
2021年 | 8篇 |
2020年 | 20篇 |
2019年 | 17篇 |
2018年 | 18篇 |
2017年 | 15篇 |
2016年 | 11篇 |
2015年 | 10篇 |
2014年 | 13篇 |
2013年 | 17篇 |
2012年 | 17篇 |
2011年 | 27篇 |
2010年 | 15篇 |
2009年 | 17篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1968年 | 2篇 |
1963年 | 1篇 |
排序方式: 共有272条查询结果,搜索用时 15 毫秒
11.
利用60 Coγ射线对紫色马铃薯品种黑美人萌芽薯块进行诱变处理。诱变材料表型鉴定结果表明,辐照剂量与出苗率呈显著负相关,其半致死剂量为70Gy,致死剂量为80Gy。辐照处理能显著延缓出苗时间,导致叶片减少、茎杆变细、植株变矮。高剂量处理可提高分枝数。与CK相比,各处理结薯数差异不显著。单株产量随辐照剂量增加而降低,CK处理显著高于其他处理。在表型鉴定的基础上,利用SSR分子标记对辐射材料进行DNA检测。10对引物集团选择结果表明,6对具有多态性,共获得10条多态性条带,平均每对引物有1.7条。单株检测共获得扩增条带28条,其中8条有多态性,多态性比率为28.9%。说明,辐射可引起紫色马铃薯黑美人表型和DNA水平的变异。 相似文献
12.
13.
以越南河内(Hanoi)、江西吉水(Jishui)、湖南资兴(Zixing)3个产地1年生越南安息香幼苗为试材,采用人工模拟低温处理技术进行低温处理,测定电解质外渗率,并配合Logistic方程对不同产地枝条的半致死温度(LT50)进行了拟合;测定低温处理下各产地越南安息香的MDA含量、根系活力,并观察不同产地越南安息香1年生幼苗的恢复情况.结果表明,3个产地越南安息香耐低温能力差异显著,半致死温度值LT50在-14.93~-9.48℃之间,抗寒性强弱排序依次为:Zixing> Jishui> Hanoi;幼苗叶片MDA含量、根系活力及抽条指数均反映出产地抗寒性强弱与半致死温度基本一致. 相似文献
14.
Dao Ha Viet Le Hy Ho Khanh Le Thao Thi Thu Pham Ky Xuan Bui Minh Quang Chan Leo Lai 《Fisheries Science》2022,88(6):821-830
Fisheries Science - Recently, suspected ciguatera fish poisoning (CFP) cases caused by the consumption of moray eels, popular seafood for locals and tourists, have been reported in Viet Nam.... 相似文献
15.
An isocratic liquid chromatographic (LC) technique is described for the determination of benzoic acid and sorbic acid in foods such as beverages, fruits, seafood, vegetables, sauces, and dairy, bakery, and confectionery products. A C18 column is used with methanol-phosphate buffer (5 + 95) as mobile phase and 4-hydroxyacetanilide or 3,5-dinitrobenzoic acid as internal standard. Sample preparation is simple, rapid, and produces a sample extract that has a minimum effect on the column performance and life. Specificity of the method was checked against common food additives such as L-ascorbic acid, caffeine, artificial sweeteners (saccharin, cyclamate, aspartame), antioxidants (BHT, BHA) and artificial colors. Also described are 2 procedures for confirmation of the preservatives, using either redox reaction of sorbic acid with potassium permanganate or gas chromatography/mass spectrometry. Mean recoveries of 90-105% were obtained with a precision of 1-6% and a detection limit of 20 mg/kg for the 2 preservatives. 相似文献
16.
芦荟试管微克隆繁育中芽增殖体系的建立 总被引:1,自引:3,他引:1
研究了库拉索芦荟茎尖组织、叶盘组织和茎盘组织的离体培养特性,发现芦荟茎尖组织芽增殖效率较低,叶盘组织无再生能力,而茎盘组织是芦荟试管克隆芽增殖系建立的最佳外植体。利用茎盘组织建立微克隆增殖系与茎盘组织在茎段上的位置有关,库拉索短宿茎的中部茎段不定芽形成能力最强。细胞分裂素是诱导库拉索芦荟芽增殖的主要激素,但质量浓度过高,不定芽生长弱,玻璃化现象严重。1.0mg/L6-BA,1.5mg/LKT和0.5mg/LNAA组合的MB培养基(该培养基由MS培养基大量元素、微量元素、铁盐,B5培养基的有机物质构成)是库拉索芦荟试管苗增殖的最佳培养基。 相似文献
17.
18.
Chan FK Chun HJ Zheng L Siegel RM Bui KL Lenardo MJ 《Science (New York, N.Y.)》2000,288(5475):2351-2354
A conserved domain in the extracellular region of the 60- and 80-kilodalton tumor necrosis factor receptors (TNFRs) was identified that mediates specific ligand-independent assembly of receptor trimers. This pre-ligand-binding assembly domain (PLAD) is physically distinct from the domain that forms the major contacts with ligand, but is necessary and sufficient for the assembly of TNFR complexes that bind TNF-alpha and mediate signaling. Other members of the TNFR superfamily, including TRAIL receptor 1 and CD40, show similar homotypic association. Thus, TNFRs and related receptors appear to function as preformed complexes rather than as individual receptor subunits that oligomerize after ligand binding. 相似文献
19.
20.
Nguyen Phuong Thao Nguyen Xuan Cuong Bui Thi Thuy Luyen Tran Hong Quang Tran Thi Hong Hanh Sohyun Kim Young-Sang Koh Nguyen Hoai Nam Phan Van Kiem Chau Van Minh Young Ho Kim 《Marine drugs》2013,11(8):2917-2926
Inflammation is important in biomedical research, because it plays a key role in inflammatory diseases including rheumatoid arthritis and other forms of arthritis, diabetes, heart disease, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, and even cancer. In the present study, we describe the inhibitory effect of crude extracts and steroids isolated from the starfish Astropecten polyacanthus on pro-inflammatory cytokine (Interleukin-12 (IL-12) p40, interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α)) production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs). Among those tested, compounds 5 and 7 showed potent inhibitory effects on the production of all three pro-inflammatory cytokines with IC50 values ranging from 1.82 ± 0.11 to 7.00 ± 0.16 μM. Potent inhibitory activities were also observed for compound 1 on the production of IL-12 p40 and IL-6 with values of 3.96 ± 0.12 and 4.07 ± 0.13 μM, respectively, and for compounds 3 and 4 on the production of IL-12 p40 with values of 6.55 ± 0.18 and 5.06 ± 0.16 μM, respectively. Moreover, compounds 2 (IC50 = 34.86 ± 0.31 μM) and 6 (IC50 = 79.05 ± 2.05 μM) exhibited moderate inhibitory effects on the production of IL-12 p40, whereas compounds 3 (IC50 = 22.80 ± 0.21 μM) and 4 (IC50 = 16.73 ± 0.25 μM) moderately inhibited the production of TNF-α and IL-6, respectively. 相似文献