查询词典 precursors

It is possible that atypical perilobular hemangiomas or atypical hemangiomas are precursors to angiosarcoma, but this relationship remains to be demonstrated.

不典型小叶周围血管瘤或不典型血管瘤可能是血管肉瘤的前驱病变，但这种相关性尚需要进一步证实。

The titanium silicide fims were prepared on glass substrate by atmospherical pressure chemical vapor deposition using SiH_4 and TiCl_4 as the precursors and diluted N_2,simulated the technics of coating on line,in the deposition reaction temperature about 640-730℃.

模拟在线镀膜工艺，采用APCVD方法，以普通载玻片作为基板，硅烷(SiH_4)、四氯化钛(TICl_4)为先驱气体，氮气(N2)稀释，沉积反应温度在640～730℃之间，制备硅钛化合物薄膜。

The results showed that precursor feeding (phenylanine, sodium acetate and benzamide) and mixed sugar as production medium resulted in significant increase of taxol production not only in the one-liquid-phase cultures of Taxus chinensis var. mairei but also in the two-liquid-phase cultures. And the integrated function of precursor feeding and mixed sugar in the two-liquid-phase cultures gave more significant increase of taxol production significant increase of taxol production, which was four times more than that of the control (the one-liquid-phase culture without precursors and mixed sugar).

结果表明前体饲喂（苯丙氨酸，醋酸钠和苯甲酰胺）和蔗糖与麦芽糖配伍作为生产培养基糖源不仅对红豆杉细胞悬浮培养，而且对其两液相培养的紫杉醇产量提高均有明显的促进作用，与对照组相比，在南方红豆杉细胞两液相培养中，采用前体饲喂和蔗糖与麦芽糖配伍作为生产培养基糖源，紫杉醇产量提高4倍多。

N,N′-Disubstituted ureas,used as intermediates for synthesis of pesticides,resin precursors and carbamates,were synthesized from carbon dioxide and primary amines(namely n-propylamine,n-butylamine,n-amylamine,n-hexylamine,benzylamine and aniline) over organic base catalysts.

以有机碱为催化剂，CO2与伯胺反应合成了N，N′-二取代脲；考察了有机碱种类、伯胺碳链长度、反应温度、CO2压力、反应时间、催化剂用量对合成反应的影响。

N,N′-Disubstituted ureas,used as intermediates for synthesis of pesticides,resin precursors and carbamates,were synthesized from carbon dioxide and primary amines(namely n-propylamine, n-butylamine ,n-amylamine,n-hexylamine,benzylamine and aniline) over organic base catalysts.

以正丁胺为反应基质、TBD为催化剂，合成N，N′-二丁脲的最佳反应条件为：反应温度180℃，CO2压力10.0M Pa，反应时间10h，TBD摩尔分数5.0%；在此条件下，N，N′-二丁脲的收率为81.8%；红外光谱表征结果表明，合成的产物为N，N′-二丁脲。

Betulin, a naturally occurring triterpene, available in abundance up to 10% dry weight of bark from white birch bark, seems to be an ideal starting material for the synthesis of betulinic acid.During a discovery effort from natural resources, in order to seek new biologically active compounds, reaearch on chemical modifications of valuable precursors have been demonstrated to be an effective path to resolve the water solubility problem and increase bioavailability.

从自然界寻找先导活性化合物，再进行结构修饰，试图提高其活性，降低其毒副作用，并提高其水溶性，是创新药物的一条重要思路，而且在新药研制中也得到了很好的应用并取得了显著的成绩。

Objective To establish an HPLC-UV-ELSD method for determination of artemisinin and its related biosynthetic precursors in leaves of Artemisia annua.

目的HPLC-UV-ELSD联用建立黄花蒿叶片中青蒿素及其生合成相关倍半萜的含量测定方法。

The promoted taxanes production by addition of precursors can not be explained completely with taxol biosynthetic pathway presumed.

依据已推测的生物合成途径不能完全解释已证明有效的前体对紫杉烷生物合成的影响。

"This virus has followed the pattern of all historic pandemics, and we've missed some precursors out there and we've missed some signals," Dr. Cardona said.

Cardona博士表示，此病毒遵循著之前历史上大流行的模式，我们错过了一些先驱信号。

Additionally, the synthesisof the key intermediates, cinnamyl aryl ethers was made an investigation andstudy. This improved synthetic method for cinnamyl aryl ethers may be alsoapplied to many benzofuranoid neolignans precursors.

此外，对关键中间体桂皮基芳香醚的合成进行了较为深入的研究，改良的成醚法可适用于许多苯骈呋喃类新木脂素前体的合成。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。