全文获取类型
收费全文 | 559篇 |
免费 | 32篇 |
国内免费 | 3篇 |
专业分类
林业 | 34篇 |
农学 | 43篇 |
基础科学 | 4篇 |
93篇 | |
综合类 | 52篇 |
农作物 | 93篇 |
水产渔业 | 61篇 |
畜牧兽医 | 169篇 |
园艺 | 21篇 |
植物保护 | 24篇 |
出版年
2024年 | 1篇 |
2022年 | 23篇 |
2021年 | 16篇 |
2020年 | 16篇 |
2019年 | 17篇 |
2018年 | 19篇 |
2017年 | 21篇 |
2016年 | 22篇 |
2015年 | 20篇 |
2014年 | 25篇 |
2013年 | 30篇 |
2012年 | 27篇 |
2011年 | 35篇 |
2010年 | 34篇 |
2009年 | 32篇 |
2008年 | 29篇 |
2007年 | 37篇 |
2006年 | 34篇 |
2005年 | 22篇 |
2004年 | 24篇 |
2003年 | 26篇 |
2002年 | 20篇 |
2001年 | 16篇 |
2000年 | 10篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有594条查询结果,搜索用时 15 毫秒
41.
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
42.
Rakib MA Kim YS Jang WJ Choi BD Kim JO Kong IK Ha YL 《Journal of agricultural and food chemistry》2010,58(22):12022-12030
The protective effect of c9,t11-conjugated linoleic acid (CLA) on the inhibition of gap junctional intercellular communication (GJIC) was examined in a human mammary epithelial cell line (MCF-10A) treated with 12-O-tetradecanoylphorbol-13-acetate (TPA), relative to t10,c12-CLA isomer. TPA inhibited GJIC in a dose-dependent and reversible manner and was associated with connexin 43 phosphorylation. Pretreatment of 20 μM c9,t11-CLA for 24 h prior to 60 nM TPA for 1 h prevented the inhibition of GJIC by reducing the phosphorylation of connexin 43 via suppressing extracellular signal-regulated kinases (ERK1/2) activation. Reactive oxygen species (ROS) accumulation by TPA was attenuated by c9,t11-CLA. The efficacy of c9,t11-CLA in protecting inhibition of GJIC, connexin 43 phosphorylation, and ROS production was superior to that of t10,c12-CLA. These results suggest that c9,t11-CLA, including t10,c12-CLA, prevents the carcinogenesis of MCF-10A cells by protecting down-regulation of GJIC during the cancer promotion stage, and lack of their toxicities could be an excellent indicator for the chemoprevention of breast cancer. 相似文献
43.
44.
45.
Chutipong Chiamkunakorn Vimbai Irene Machimbirike Saengchan Senapin Pongsak Khunrae Ha Thanh Dong Triwit Rattanarojpong 《Journal of fish diseases》2019,42(11):1629-1636
Detection of tilapia lake virus (TiLV) in tilapines is mainly from visceral organs of killed fish. However, lethal sampling might not be viable to broodstock and economically important ornamental cichlids. To contribute towards screening of the virus in asymptomatic infected fish, a subclinically infected population of Nile tilapia adults obtained from a local farm was preliminarily tested to compare different non‐lethal sampling methods, for example liver biopsy, gill biopsy, fin clip, mucus, faeces and blood for detection of TiLV. Only liver and blood samples gave positive results by PCR. Since blood sampling is relatively simpler, it was further used for five naturally co‐cultured juvenile fish species from above‐mentioned farm including 40 red tilapia broodstock and 20 Nile tilapia adults from two other different farms. The results showed that from the tested fish, 4 of 5 Nile tilapia, 2 of 5 hybrid red tilapia and 3 of 5 giant gourami blood samples tested positive, while 38 of 40 blood samples of red tilapia tested positive for TiLV in second‐step PCR. Sequencing representative PCR amplicons of positive samples confirmed sequence identity to TiLV. In conclusion, both blood and liver biopsy are practical non‐destructive sampling platforms for TiLV screening in cichlids with blood being more convenient, especially for tilapia broodstock. 相似文献
46.
Joohyun Jung DVM MS Mincheol Choi DVM PHD Jinhwa Chang DVM Sungjoon Won DVM Woqjo Chung DVM Hojung Choi DVM MS Kichang Lee DVM MS Junghee Yoon DVM PHD Hyunkwon Ha MD PHD 《Veterinary radiology & ultrasound》2003,44(6):642-645
This study was performed to evaluate and optimize a small bowel contrast technique using barium and methylcellulose in dogs. Ten healthy dogs underwent both a conventional upper gastrointestinal study that used only barium and a modified study that used barium and methylcellulose. The control group received 10 mL/kg of 40% barium suspension. Experimental groups were divided into three subgroups given 15 mL/kg of different viscosities (low, moderate, and high viscosity) of 0.5% methylcellulose after 4 mL/kg of 40% barium suspension. Compared with the control group, dogs receiving methylcellulose had higher-quality upper gastrointestinal studies. Moderate viscosity of methylcellulose was superior to the other methylcellulose groups. In conclusion, the use of methylcellulose is a simple and effective method for improving the image quality in an upper GI examination. 相似文献
47.
6[8'(Z)-pentadecenyl]salicylic acid, otherwise known as anacardic acid (C15:1), inhibited the linoleic acid peroxidation catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, type 1) with an IC50 of 6.8 microM. The inhibition of the enzyme by anacardic acid (C15:1) is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Dixon plots indicates that anacardic acid (C15:1) is a competitive inhibitor and the inhibition constant, KI, was obtained as 2.8 microM. Although anacardic acid (C15:1) inhibited the linoleic acid peroxidation without being oxidized, 6[8'(Z),11'(Z)-pentadecadienyl]salicylic acid, otherwise known as anacardic acid (C15:2), was dioxygenated at low concentrations as a substrate. In addition, anacardic acid (C15:2) was also found to exhibit time-dependent inhibition of lipoxygenase-1. The alk(en)yl side chain of anacardic acids is essential to elicit the inhibitory activity. However, the hydrophobic interaction alone is not enough because cardanol (C15:1), which possesses the same side chain as anacardic acid (C15:1), acted neither as a substrate nor as an inhibitor. 相似文献
48.
Gamblin SJ Haire LF Russell RJ Stevens DJ Xiao B Ha Y Vasisht N Steinhauer DA Daniels RS Elliot A Wiley DC Skehel JJ 《Science (New York, N.Y.)》2004,303(5665):1838-1842
The 1918 influenza pandemic resulted in about 20 million deaths. This enormous impact, coupled with renewed interest in emerging infections, makes characterization of the virus involved a priority. Receptor binding, the initial event in virus infection, is a major determinant of virus transmissibility that, for influenza viruses, is mediated by the hemagglutinin (HA) membrane glycoprotein. We have determined the crystal structures of the HA from the 1918 virus and two closely related HAs in complex with receptor analogs. They explain how the 1918 HA, while retaining receptor binding site amino acids characteristic of an avian precursor HA, is able to bind human receptors and how, as a consequence, the virus was able to spread in the human population. 相似文献
49.
卤虫做为一种经济动物已广泛应用于水产养殖业中,但是做为一种遗传学教学的实验材料尚无人报道过。通过多次实验,本文作者提出了一种改进后的观察卤虫染色体形态和数目的实验方法。同时,作者还例举了各种事实表明卤虫是一种很好的遗传学教学的实验材料。 相似文献
50.