نتایج جستجو برای: mechanisms of cis and trans beta lactam ring formation
تعداد نتایج: 24118100 فیلتر نتایج به سال:
nowadays in trade and economic issues, prediction is proposed as the most important branch of science. existence of effective variables, caused various sectors of the economic and business executives to prefer having mechanisms which can be used in their decisions. in recent years, several advances have led to various challenges in the science of forecasting. economical managers in various fi...
abstract since heubners (1985) pioneering study, there have been many studies on (mis) use/ non-use of articles by l2 learners from article-less and article languages. the present study investigated how persian l2 learners of english produce and interpret english definite descriptions and demonstrative descriptions. it was assumed that definite and demonstrative descriptions share the same cen...
Rhodopsin is a prototype for G protein-coupled receptors (GPCRs) that are implicated in many biological responses in humans. A site-directed (2)H NMR approach was used for structural analysis of retinal within its binding cavity in the dark and pre-activated meta I states. Retinal was labeled with (2)H at the C5, C9, or C13 methyl groups by total synthesis, and was used to regenerate the opsin ...
Fifteen novel β-lactams bearing the N-ethyl tert-butyl carbamate group 5a-o and fifteen N-(2-aminoethyl) β-lactams 6a-o were synthesized by the ketene-imine [2+2] cycloaddition reaction (Staudinger ). The cycloaddition reaction was found to be totally diastereoselective leading exclusively to the formation of the cis-β-lactam derivatives. These newly synthesized β-lactams were evaluated for the...
in chapter one we will describe definitions and preliminary results to provide the global context of our own results to be presented in detail in the subsequent chapters in chapter two we consider degree-one maps of the circle and we study their rotation set. our main result in this chapter says that if the map is topologically mixing then its rotation interval is nontrivial (that is, not reduc...
all analytical methods are generally based on the measurement of a parameter or parameters which are somehow related to the concentration of the species.an ideal analytical method is one in which the concentration of a species can be measured to a high degree precision and accuracy and with a high sensitivity. unfortunately finding such a method is very difficult or sometimes even impossible.in...
Abstract Background: Most animal studies have shown that trans-10 and cis-12 isomers of Conjugated linoleic Acid, (CLA) tend to increase insulin resistance. But the effect of equal isomers of CLA (50:50 ratios of cis-9, trans-11: trans-10, cis-12 isomers) on lipid profiles, glucose, and insulin resistance and sensitivity in postmenopausal women is not clear. Methods: In the present study, ...
For the class A β-lactamase SHV-1, the kinetic and mechanistic properties of the clinically used inhibitor sulbactam are compared with the sulbactam analog substituted in its 6β position by a CH2OH group (6β-(hydroxymethyl)penicillanic acid). The 6β substitution improves both in vitro and microbiological inhibitory properties of sulbactam. Base hydrolysis of both compounds was studied by Raman ...
در این پژوهش به منظور درک سن و محیط رسوبی سازند آسماری در برش کوه شجبیل، شمال غرب یاسوج به ضخامت 375 متر 171 نمونه برداشت گردیده است. سازند آسماری در برش مورد مطالعه با معیارهای سنگ شناختی به سه واحد مشخص تفکیک شده است. این واحد ها با داشتن شمای آهک های مسیو، ضخیم، متوسط و نازک لایه، آهک های نازک لایه ی مارنی و بعضاً مارن مشخص می گردد. در این برش تعداد 18 جنس و 29 گونه از فرامینیفرهای بنتیک شنا...
conclusions this study demonstrated the co-existence of rmtc and blandm-1 genes for the first time in turkey. the spread of this resistant type should be monitored and limited through molecular surveillance. results twenty k. pneumoniae strains showed resistance to amikacin, and 40 were resistant to gentamicin. the mic value was found to be > 512 µg/ml in five amikacin-resistant strains and > 1...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید