全文获取类型
收费全文 | 284篇 |
免费 | 16篇 |
专业分类
化学 | 265篇 |
晶体学 | 2篇 |
力学 | 1篇 |
数学 | 9篇 |
物理学 | 23篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 9篇 |
2019年 | 7篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 7篇 |
2014年 | 9篇 |
2013年 | 19篇 |
2012年 | 23篇 |
2011年 | 33篇 |
2010年 | 7篇 |
2009年 | 14篇 |
2008年 | 18篇 |
2007年 | 16篇 |
2006年 | 14篇 |
2005年 | 22篇 |
2004年 | 30篇 |
2003年 | 17篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
排序方式: 共有300条查询结果,搜索用时 578 毫秒
51.
52.
Tatsuya Oshima Akinori Suetsugu Yoshinari Baba Yuka Shikaze Keisuke Ohto Katsutoshi Inoue 《Journal of membrane science》2008
The present study examined the liquid membrane transport of the cationic protein cytochrome c, using the macrocyclic compound calix[6]arene, which is a carboxylic acid derivative, as a carrier. The transport rate was governed by carrier concentration and the pH gradient between the feed and the receiving phases, as well as the salt concentration in the aqueous phases. Transport of cytochrome c was examined using a series of calix[n]arene carboxylic acid derivatives (n = 4, 6 and 8). Cytochrome c successfully permeated membranes in the presence of the calix[6]arene derivative. Liquid membrane separation of cytochrome c from a mixture of cationic proteins was demonstrated under optimal conditions. Cytochrome c was selectively extracted by the calix[6]arene carboxylic acid derivative and 77% of the extracted cytochrome c was recovered into the receiving phase. In this liquid membrane system, which discriminates between the number of lysine residues on the surface of proteins, cationic proteins with similar molecular weights and pIs were separated with macrocyclic compounds. 相似文献
53.
We have examined the lipid peroxide levels in aclacinomycin (ACM)-treated mice by using adriamycin (ADR) as a comparative drug. There was no increase in the lipid peroxide level of the heart at either 3h or 4d after ACM administration (15 mg/kg, i.p.), although the level in the heart of ADR-treated mice was elevated to 257% of that in normal mice. The effect of ACM and its glycoside-type metabolites on the increase of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-dependent microsomal lipid peroxidation (in vitro) was weaker than that of ADR. Then, we examined the tissue concentrations of ACM. The AUC0-24h of ACM was the lowest in the heart among the tissues examined, being only 29.3% of that obtained with ADR. However, the concentrations of the glycoside-type metabolites of ACM in all tissues determined were higher than the concentration of ACM. In the heart, the T1/2 and AUC0-24h of ACM glycosides were somewhat higher than those of ADR. In conclusion, ACM and its metabolites do not lead to an increase in lipid peroxide level in the heart of mouse, and the difference in lipid peroxide increment in the mouse heart induced by ADR and ACM is independent of the tissue concentration of the drugs. 相似文献
54.
A Cell‐Targeted Non‐Cytotoxic Fluorescent Nanogel Thermometer Created with an Imidazolium‐Containing Cationic Radical Initiator
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Seiichi Uchiyama Dr. Toshikazu Tsuji Kyoko Kawamoto Dr. Kentaro Okano Eiko Fukatsu Takahiro Noro Kumiko Ikado Sayuri Yamada Yuka Shibata Dr. Teruyuki Hayashi Dr. Noriko Inada Dr. Masaru Kato Dr. Hideki Koizumi Prof. Hidetoshi Tokuyama 《Angewandte Chemie (International ed. in English)》2018,57(19):5413-5417
A cationic fluorescent nanogel thermometer based on thermo‐responsive N‐isopropylacrylamide and environment‐sensitive benzothiadiazole was developed with a new azo compound bearing imidazolium rings as the first cationic radical initiator. This cationic fluorescent nanogel thermometer showed an excellent ability to enter live mammalian cells in a short incubation period (10 min), a high sensitivity to temperature variations in live cells (temperature resolution of 0.02–0.84 °C in the range 20–40 °C), and remarkable non‐cytotoxicity, which permitted ordinary cell proliferation and even differentiation of primary cultured cells. 相似文献
55.
Furusawa M Tanaka T Ito T Nakaya K Iliya I Ohyama M Iinuma M Murata H Inatomi Y Inada A Nakanishi T Matsushita S Kubota Y Sawa R Takahashi Y 《Chemical & pharmaceutical bulletin》2005,53(5):591-593
Fourteen flavonol glycosides including two new compounds were isolated from the leaves of two Diospyros plants (D. cathayensis and D. rhombifolia). The structures of isolated compounds were determined by spectroscopic analysis. The scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical of the isolated compounds was also investigated. 相似文献
56.
To examine the nature of the adsorption and desorption branches in hysteretic adsorption isotherms of gases on mesoporous materials, we measured the temperature dependence of the adsorption and desorption isotherms of argon, oxygen, and carbon dioxide onto MCM-41 with a pore diameter of 4.4 nm. The results clearly show that in the open-ended cylindrical pores of MCM-41, capillary condensation rather than evaporation takes place near a thermodynamical equilibrium transition, as opposed to the general statement that capillary evaporation can occur via a meniscus formed at the pore mouth, and, thus, takes place at equilibrium. 相似文献
57.
Theoretical modeling of photo-induced wave propagation in liquid-crystalline Langmuir monolayers 总被引:1,自引:0,他引:1
A phenomenological model of wave propagation in photo-excited liquid-crystalline Langmuir monolayers is constructed. The spontaneous splay deformation of the liquid-crystalline order and the anisotropy of photo-excitation of molecules are taken into account in this model. Numerical simulations of the model well reproduce qualitative features of the wave propagation phenomenon observed in recent experiments. A linear stability analysis of the model equations reveals that an interplay between the spontaneous splay deformation and the anisotropy of the photo-excitation can lead to the wave propagation. 相似文献
58.
Formal total synthesis of magellanine is described. Key features in the synthesis were stereoselective Ireland-Claisen rearrangement and intramolecular Pauson-Khand reaction of exo-cyclic enynes. 相似文献
59.
60.