首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   18篇
  免费   1篇
化学   10篇
数学   6篇
物理学   3篇
  2016年   2篇
  2010年   1篇
  2008年   1篇
  2001年   1篇
  1993年   1篇
  1992年   2篇
  1990年   1篇
  1979年   1篇
  1976年   1篇
  1975年   1篇
  1970年   1篇
  1962年   1篇
  1960年   1篇
  1956年   3篇
  1954年   1篇
排序方式: 共有19条查询结果,搜索用时 31 毫秒
1.
Bulbocapnine methyl ether ( 2 ), on treatment with boron halides, affords the aporphine-1,2-diol ( 3 ), the novel aporphines 5 and 6 or the phenanthrene derivative 11 depending on the reaction conditions. 3 can be further transformed into corydine methyl ether ( 4 ); 6 has been converted to corytuberine ( 8 ). Similarly, dehydrobulbocapnine methyl ether 9 was converted to 10 .  相似文献   
2.
3.
Ohne Zusammenfassung
International Association for Analog Computation

ASICA Association Internationale pour le Calcul Analogique
  相似文献   
4.
An in vitro reporter gene assay based on human breast cancer T47D cells (ER-CALUX) was applied to examine the ability of diesel exhaust to induce or inhibit estrogen receptor (ER)-mediated gene expression. Exhaust from a heavy-duty diesel engine was either treated by iron- or copper/iron-catalyzed diesel particulate filters (DPFs) or studied as unfiltered exhaust. Collected samples included particle-bound and semivolatile constituents of diesel exhaust. Our findings show that all of the samples contained compounds that were able to induce ER-mediated gene expression as well as compounds that suppressed the activity of the endogenous hormone 17beta-estradiol (E2). Estrogenic activity prevailed over antiestrogenic activity. We found an overall ER-mediated activity of 1.63 +/- 0.31 ng E2 CALUX equivalents (E2-CEQs) per m(3) of unfiltered exhaust. In filtered exhaust, we measured 0.74 +/- 0.07 (iron-catalyzed DPF) and 0.55 +/- 0.09 ng E2-CEQ m(-3) (copper/iron-catalyzed DPF), corresponding to reductions in estrogenic activity of 55 and 66%, respectively. Our study demonstrates that both catalytic DPFs lowered the ER-mediated endocrine-disrupting potential of diesel exhaust.  相似文献   
5.
rac-1,2,10-Trimethoxy-aporphine ( 14 ) and rac-2-ethoxy-10,11-dimethoxyaporphine ( 27 ) have been synthesized from the 3-phenylphenethylamines 9 and 22 by a new route. The 8-phenyl-3,4-dihydroisoquinolines 11 and 24 , the oxo-aporphines 12 and 25 and the rac-nor-aporphines 13 and 26 were obtained as intermediates.  相似文献   
6.
7.
A modification of the biotin synthesis of Goldberg & Sternbach is described, enantiomers being separated in the first steps and wrong isomers recyclised. The conversion of the lactone 15 to the thiolactone 16 is done by a new method using potassium thioacetate in high boiling solvents.  相似文献   
8.
9.
10.
Ohne Zusammenfassung
Book reviews

Notices bibliographiques
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号