Search results for "Esteri"
showing 10 items of 220 documents
Discorso interiore/discorso esteriore. In dialogo con Giovanni Manetti
2019
A partire da un contributo di Giovanni Manetti (2016) si ripercorre la contrapposizione fra linguaggio esteriore e linguaggio interiore nella tradizione filosofica greca. Si delineano due posizioni di fondo: la posizione discontinuista, rappresentata dagli Stoici, nega etica e razionalità agli animali, perché privi di 'linguaggio interiore' (logos endiathetos), ossia di ragione (logos), anche se capaci di imitare il linguaggio proferito (logos prophorikòs). All'estremo opposto, la posizione continuista, rappresentata dagli Accademici e dagli Scettici, argomenta a favore di una continuità cognitiva fra uomo e animale. Scopo dell'articolo è mostrare che la posizione discontinuista non si orig…
Iedzimtu hiperholesterinēmiju izraisošo mutāciju noskaidrošana Latvijas populācijā
2015
Iedzimta hiperholesterinēmija (IH) ir nopietna ģenētiskā slimība, kurai raksturīgs paaugstināts zema blīvuma lipoproteīnu holesterīna daudzums asinīs. IH ir riska faktors sirds-asinsvadu slimībām. Šīs slimības cēlonis visbiežāk ir mutācijas četros gēnos – LDLR, APOB, PCSK9 un LDLRAP1. Darba mērķis bija noskaidrot IH fenotipu izraisošās mutācijas četros gēnos Latvijas populācijā, izmantojot liela apjoma paralēlās sekvenēšanas metodi. Darbā tika analizētas mutācijas 98 pacientos, kuriem ir aizdomas par IH. Ģenētisko variāciju noteikšanai tika izmantota jaunās paaudzes pusvadītāja sekvenēšanas metode. Rezultātā tika atrastas 97 dažādas nomaiņas, vairums no kurām ir APOB un LDLR gēnos, bet vism…
Proteīnu linkera sintēze biokonjugācijai
2021
Proteīnu linkera sintēze biokonjugācijai. Bušs R., zinātniskais vadītājs docents Igors Kļimenkovs. Kursa darbs, 35 lapaspuses, 32 attēli, 38 literatūras avoti. Latviešu valodā. PROTEĪNU BIOKONJUGĀCIJA, PIRIDĪN-2-KARBALDEHĪDS, NHS ESTERI, LIZĪNA BIOKONJUGĀCIJA Kursa darba ietvaros aprakstīts viens no iespējamajiem sintēzes ceļiem, lai iegūtu 2,5-dioksopirolidīn-1-il-5-(4-(((6-(hidroksimetil)piridīn-2-il)metoksi)metil)piperazīn-1-il)-5- okso-pentanoātu, ko būtu iespējams izmantot kā linkeri biokonjugācijai.
Holskābes metilestera solvātu desolvatācija
2016
Holskābes metilestera solvātu desolvatācija. Trimdale A., darba vadītājs Dr. Chem. Bērziņš A. Bakalaura darbs, 64 lappuses, 41 attēls, 4 tabulas, 7 pielikumi, 36 literatūras avoti. Latviešu valodā. Darbā apkopota informācija par holskābes metilesteri, polimorfismu, solvātiem un pētījumos izmantotajām metodēm: pulvera rentgendifraktometriju, termiskajām analīzes metodēm un IS spektroskopiju. Eksperimentālajā daļā veikta dažādu holskābes metilestera solvātu iegūšana. Ar pulvera rentgendifraktometru gan tradicionālā režīmā, gan aprīkotu ar karsēšanas un klimatisko apstākļu kameru, kā arī ar derivatogrāfiju pētīts un noskaidrots iegūto solvātu desolvatācijas mehānisms un identificēti desolvatāc…
In vivo investigations on microcirculatory disturbances induced by crenated erythrocytes following norepinephrine application
1974
Using a special apparatus for high resolution cinephotomicrography, which allows simultaneous observation and recording of microcirculatory changes, alterations in blood flow patterns and in red cell shape during norepinephrine acting have been studied. Under physiological conditions, and during slowing of capillary blood flow due to gradual removing of 20–25% of the circulating blood volume, the normal red cells are extremely deformable while passing through mesenteric capillaries. After application of norepinephrine a general arteriolar constrictive response in the bowel wall occurs, causing a further slowing of the capillary blood flow in the mesentery. Under these circumstances the eryt…
Determination of fatty alcohol ethoxylates by derivatisation with maleic anhydride followed by liquid chromatography with UV-vis detection.
2007
The esterification of fatty alcohol ethoxylates (FAEs) by melting with maleic anhydride has been studied in the presence of urea. The reaction rate and yield of non-ethoxylated and ethoxylated alcohols increase largely when grinded urea is suspended in the reaction medium, a 100% yield being achieved at 80 degrees C in 15 min. The procedure is tolerant to the presence of large amounts of water. The UV-vis response factors of the derivatives of individual FAE oligomers vary little with the number of carbon atoms in the alkyl chain, n, and the number of ethylene oxide units, m. Derivatised samples of industrial FAE mixtures, cleaning products and river and sea waters were chromatographed on a…
Detection of a plant enzyme exhibiting chlorogenate-dependant caffeoyltransferase activity in methanolic extracts of arbuscular mycorrhizal tomato ro…
2012
When Glomus intraradices-colonised tomato roots were extracted in methanol at 6 degrees C, chlorogenic acid (5-caffeoylquinic acid), naturally present in the extract, was slowly converted by transesterification into methyl caffeate. The progress of the reaction could be monitored by HPLC. The reaction only occurred when the ground roots were left in contact with the hydro-alcoholic extract and required the presence of 15-35% water in the mixture. When the roots were extracted in ethanol, chlorogenic acid was transformed to ethyl caffeate in the same conditions. The reaction was also detected in Glomus mosseae-colonised tomato root extracts. It was also detectable in non-mycorrhizal root ext…
Le determinanti della produttività: investimenti diretti e commercio estero
2010
Fatty acids liberated from low-density lipoprotein trigger endothelial apoptosis via mitogen-activated protein kinases.
2005
Enzymatic modification of low-density lipoprotein (LDL) as it probably occurs in the arterial intima drastically increases its cytotoxicity, which could be relevant for the progression of atherosclerotic lesions. LDL was treated with a protease and cholesterylesterase to generate a derivative similar to lesional LDL, with a high content of free cholesterol and fatty acids. Exposure of endothelial cells to the enzymatically modified lipoprotein (E-LDL), but not to native or oxidized LDL, resulted in programmed cell death. Apoptosis was triggered by apoptosis signal-regulating kinase 1 dependent phosphorylation of p38. Depletion and reconstitution experiments identified free fatty acids (FFA)…
ChemInform Abstract: Selective Formal Transesterification of Fluorinated 2-(Trimethylsilyl)ethyl α-Imino Esters Mediated by TBAF.
2008
The scope of the transesterification reaction between β-fluorinated α-imino esters and various electrophiles in the presence of TBAF as fluorine source is described. The reaction is highly selective for alkyl iodides, bromides, and mesylates, while alkyl chlorides react at a significantly slower rate and tosylates do not react under the reaction conditions. This methodology represents a simple and useful alternative for the preparation of a wide variety of fluorinated α-imino esters.