El hombre dej atrs su naturaleza animal. El hombre y la naturaleza conforman una unidad indivisible. La naturaleza fue hecha exclusivamente para el hombre. El hombre produce indirectamente su vida material. Banco de preguntas de Biologia - Free download as PDF File (.pdf), Text File (.txt) or read online for free. Banco de preguntas de qumica Los grupos de preguntas que se incluyen en las pruebas de qumica son los siguientes: Aspectos analticos de mezclas y sustancias: Se refiere a los atributos que permiten distinguir a un material de otro, a la determinacin de qu estn hechos los materiales y cunto tienen de cada constituyente. Oct 31, 2015 - Key English Test Cambridge Tipo Icfes Con Respuestas. Prueba tipo icfes biologia pdf tipo icfes de biologia con respuestas. Banco de Preguntas ICFES todas las reas con respuestas. Pdf icfes filosofia. Para los sofistas, la naturaleza moral del hombre es moldeable y perfectible a travs de la razn y de la persuasin de la palabra, motivo por el cual se hace necesario que el hombre adquiera conocimiento sobre A. Verdades absolutas como la libertad. Las leyes del saber cientfico. Las virtudes del alma. Conocimientos objetivos como la fsica. Si bien para Santo Toms el hombre es una creacin de Dios, quien adems del ser le da el sentido a su existencia, para Descartes el hombre es una res cogitans o cosa pensante. Banco de preguntas de inglesLa prueba de ingles se encuentra organizada en los. TAREA DE BIOLOGIA 2.docx. Prueba tipo icfes biologia pdf Donde aparecen las respuestas del banco de preguntas para saber. Test tipo icfes de biologia Cristian Fernando Rodriguez 31 de enero de 2014, 11: 07 p. El pensamiento es el que le da el sentido a la vida del hombre y le hace consciente de existir, porque A. A travs del pensamiento el hombre alcanza su felicidad. A travs del pensamiento se reconoce como creacin de Dios. A travs del pensamiento se percibe a s mismo como existente. Introduction Marine organisms are a prolific source of structurally diverse and bioactive compounds ( ). Interestingly, during the 2002-2011 period, 132 new compounds of marine origin with anti-HIV activity on different stages of the replication cycle were reported ( ). Viral diseases are hard to treat and vaccine development against these diseases is still a major challenge and continues to elude the majority of drug discovery programs. Highly active antiretroviral therapy (HAART) is considered the best alternative of treatment against viral infectious diseases (, ). HAART´s main components for treating AIDS for instance, are nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors (PIs), although new targets are constantly explored ( ). This kind of therapy has turned AIDS from being a mortal disease to becoming a treatable chronic condition, improving life quality and expectation. On the other side, Acyclovir ® and its related compounds constitutes the first alternative for treating genital and oral herpes infections caused by Herpes Simplex Viruses 1 and 2 due their unsurpassed capacity to attenuate the symptoms and manifestations of these infections ( ). As mentioned earlier, although HAART is not a definite cure for viral infections, it allows management of viral diseases and improves the life quality of patients and is widely used for treating AIDS. However, the emergence of resistant strains and the various side effects reported for antivirals used in HAART together with lack of efficacy of some of these substances, constitute a major challenge to overcome in order to improve this therapy (, ). Dolabellanes are diterpenes that have been isolated from natural sources such as plants ( ), fungi ( ), and several marine organisms, mainly brown algae, cnidarians, and sponges ( ). Structurally, they are produced by the ring formation between positions 1,11 and 10,14 in the geranyl-geraniol pyrophosphate to constitute a bicyclic [9.3.0] fused ring. Diterpenes usually exhibit a very interesting range of biological activity including antitumoral ( ), cytotoxic (, ) antiparasitary ( ), besides a remarkable antiviral activity. Different dolabellanes with antiviral properties have been isolated from brown algae from the genus Dictyota (, ). Banco De Preguntas Biologia Icfes Pdf 2016Dolabellanetriol isolated from Dictyota friabilis (as D. Pfaffii) is the most studied so far, due to its potent inhibition of the human immunodeficiency virus (HIV-1) and the herpes simplex virus (HSV-1) (, ). How to crack irdeto 2 encryption algorithm download. Studies concerning the mechanism of action of dolabellanetriol concluded that the molecule acts as a non-competitive HIV-1 reverse transcriptase inhibitor and classifies it into the non-nucleoside reverse transcriptase inhibitors category (NNRTIs) ( ). However, despite the significant evidence on the antiviral activity of dolabellane diterpenes, very little has been reported on the antiviral properties of dolabellanes isolated from marine sources other than brown algae. Brown algae are an important source of dolabellane diterpenes of marine origin ( ), but soft corals also constitute a prolific source of such compounds, and in several cases significant ecological roles have been attributed to those ( ). Most dolabellane diterpenes have been isolated from the Alcyonacean genus Clavularia and the Octocorallian genus Eunicea ( ). The Colombian Caribbean harbors are large and possess diverse communities of Eunicea soft corals ( ). In some of our previous studies, the soft coral Eunicea laciniata collected in Santa Marta, yielded the dolabellane diterpenes β-araneosene ( 1) and dolabellatrienone ( 2) as major compounds in the organic extract ( ). Recently, we reported the anti-HIV activity of those compounds and some semisynthetic derivatives ( ). Natural compounds showed low antiviral activity and they did not have considerable cytotoxic activity. On the other hand, semisynthetic derivatives were 100 times more active compared with their precursors inhibiting HIV-1 replication without a considerable increase in their cytotoxicity. Amibios8 utilities download. Headquartered in Atlanta, AMI has locations in the U.S. (AMI) has dedicated its resources to providing OEMs, resellers and systems integrators with leading edge computer technologies. This privately held company, best known for its Basic Input/Output Systems or BIOS, also supplies its state-of-the-art hardware, software, utilities and RAID controllers to over 55 percent of today's high-tech manufacturers. About AMI Founded in 1985, American Megatrends Inc. Thus, dolabellane diterpenes are very interesting candidates for the development of new antivirals. As a part of our ongoing research on antivirals from marine sources, herein we show the characterization of six dolabellane diterpenes from the soft corals Eunicea laciniata and Eunicea asperula, collected at Santa Marta, Colombian Caribbean as well as the evaluation of their antiviral activity assessed as the inhibition of HSV-1 replication and cytotoxic activity. General Optical rotation was measured on a ADP440+, Bellingham +Stanley polarimeter. 1H and 13C-NMR spectra were recorded on a Bruker AVANCE 400 (400 MHz) and Bruker AVANCE (300 MHz) spectrometers as dilute solutions in CDCl 3 (δH 7.26 δC 77.0) at room temperature, unless stated otherwise. Chemical shields are quoted in parts per million (ppm) relative to residual solvent peaks and coupling constants are quoted in Hertz. Kovats index determination and mass spectra analyses were performed on an Agilent Technologies 7890B chromatograph equipped with a HP-5MS column (30 m x 0.25 mm x 0.25 µm) and an Agilent 5977A MSD mass detector using electronic impact ionization (70 eV) at 290 °C. Banco De Preguntas Biologia Icfes Pdf 2017Mass detection range was selected between m/z 20 to 800. For each analysis, 1 µL of a 1 mg/mL solution in acetone was injected in split mode (1:30) at an injector temperature of 260 °C. Helium 5.0 grade was used as carrier gas maintaining a 1 mL/min flux. Temperature program started at 40 °C maintaining this temperature for 1 min, followed by a temperature ramp as follows: 6 °C/min until 100 °C, 4 °C/min until 260 °C, 10 °C/min until 290°C, maintaining at 290 °C for 15 min. Kovats indexes were calculated based on a mixture of paraffins from C10 to C25 (Dr Ehrenstorfer, Augsburg, Germany). Thin layer chromatography was developed on aluminum plates precoated with silica gel 60G F 254 from Merck. Plates were visualized under ultraviolet light (λ = 254 nm) and 5% cerium ammonium sulfate with 10% sulfuric acid in methanol followed by heating. Banco De Preguntas Biologia Icfes Pdf DeSilica gel (0.043–0.060 mm, Merck), Sephadex LH-20 (GE Healthcare Life Siences), and HyperSep™ Diol cartridges (Thermo Scientific™) were employed for column chromatography separations. Solvents of analytical quality were employed and they were acquired from Merck. Organism extraction and compound isolation The sample of Eunicea laciniata was cut in small pieces and extracted with dichloromethane (DCM) four times. The extract was filtered and concentrated under vacuum yielding a dark green oil (13.8 g). The extract was separated by flash column chromatography (20 cm x 6 cm) eluting with 500 mL mobile phases of increasing polarity (hexane:toluene 90:10 to 50:50, toluene, toluene:ethyl acetate 50:50, ethyl acetate, ethyl acetate:methanol 50:50, methanol) to yield nine fractions (FL1 to FL9) according to their TLC profile.
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