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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Study on the Secondary Metabolites and Their Biological Activities from the Soft Coral Klyxum molle

Hsu, Fang-Jung 16 August 2010 (has links)
In order to discover for bioactive compounds, we have studied the chemical constituents from the organic extracts of soft coral Klyxum molle. This study had led to the isolation of 16 eunicellin-type diterpenoids, including ten new compounds, klymollins A¡VJ (1¡V10), along with six know compounds 11¡V16. The structures of compounds 1¡V16 were established by spectroscopic methods and by comparison of the spectral data with those of the related known compounds. It is noteworthy to mention that compounds 1¡V10 represent the first example of eunicellins possessing a C-11/C-17 epoxide. The absolute configuration of 4 was determined using a modified Mosher¡¦s method. The cytotoxicity of compounds 1¡V8 and 11¡V16 against the A549 (human lung epithelial cells), HepG2 (human hepatocellular carcinoma), Hep3B (human hepatocellular carcinoma), MCF-7 (human breast adenocarcinoma)¡BMDA-MB231 (human breast adenocarcinoma) tumor cell lines were determined. Compound 11 showed cytotoxicity toward A549 tumor cells (IC50 value of 3.14 £gg/mL) and compounds 15 and 16 were found to exhibit cytotoxicity toward HepG2 tumor cell (IC50 values of 3.82 and 2.50 £gg/mL). Compounds 6 and 7 were found to show significant activity against the accumulation of the pro-inflammatory iNOS and COX-2 protein at 1 £gM.
72

The Studies of Chemical Constituents and their Biological Activities from the Formosa Soft Coral Cladiella krempfi

Tai, Chi-jen 25 August 2010 (has links)
Eighteen eunicellin-based diterpenoids were isolated from the organisms of the soft coral Cladiella krempfi. According to the results of 1D and 2D NMR spectroscopic experiments, the structures of these marine natural products were established. Among them, krempfielins A¡VJ (1¡V10) are new compounds, and sclerophytin B (11), sclerophytin F (12), litophynols A (13), (1R*, 2R*, 3R*, 6S*, 7S*, 9R*, 10R*, 14R*)-3-butanoyloxycladiell-11(17)-en-6,7-diol (14), litophynin I monoacetate (15), (1R*, 2R*, 3R*, 6S*, 9R*, 10R*, 14R*)-3- acetoxycladiell-7(16)-11(17)-dien-6-ol (16), 6-acetoxy litophynin E (17) and litophynin F (18) are the previously isolated compounds. The anti-inflammation activity of these compounds at 10 £gM was studied. The results showed that 9, 14 and 17 effectively inhibited more than 80% expression of iNOS protein in LPS stimulated RAW 264.7 macrophage cells, and 5, 6, 10, 13 and 18 inhibited more than 60% expression of iNOS protein. Also, 9, 12, 16 and 18 were found to inhibit the expression of COX-2 protein in LPS stimulated RAW 264.7 macrophage cells to 52.5, 79.2, 82.2 and 48.2%. Cytotoxicity of these compounds were tested by the MTT assay using five human cancer cell lines (A549, BT483, H1299, Hep3B and SAS) and one normal cell line, BEAS2B. Compounds 9, 10, 11, 14, 17 and 18 were shown to exhibit cytotoxic activity.
73

Studies on the Secondary Metabolites and Biological Activities from the Formosan Soft Coral Sinularia flexibilis

Shih, Huei-Jyun 14 February 2011 (has links)
In order to discover bioactive secondary metabolites, we have studied the chemical constituents from the organic extracts of soft coral Sinularia flexibilis. This study had led to the isolation of eighteen natural compounds 1¡V18, including seven new cembrane-type diterpenoids, flexibilisolides C¡VG (1, 2, 3, 6, 7), flexiblilisin C (5), 11,12-secoflexibillin (4) along with eleven know compounds. The structure of compounds 1¡V18 were established by detailed spectral data analysis (IR, MS, 1D, 2D NMR) and by comparison of the spectral data with those of the related known compounds. The cytotoxicity of compounds 1¡V6, 8¡V14, 16¡V18 against the Hela (human cervical epitheloid carcinoma), SK-Hep1 (human liver carcinoma), and B16 (human melanin carcinoma) tumor cell lines were screened. Compounds 1, 9, 12, and 13 showed moderate activity toward the Hela and SK-Hep1 tumor cells. Compound 12 also showed moderate activity toward the B16 cells, and compound 14 showed activity toward the Hela cells. On the other hand, compounds 1, 9, 13, and 17 were found to show significant activity against the accumulation of the pro-inflammatory iNOS and COX-2 protein at 10 £gM. Compounds 2¡V4, 7, 8, 10, 14, 16 were found to show activity against the accumulation of the pro-inflammatory iNOS protein at 10 £gM.
74

Combining Sphere Decoding with LORD Search For MIMO Detector

Wang, Yao-Temr 29 July 2011 (has links)
It is know that the LORD (Layered Orthogonal Lattice Detector) and the sphere decoding achieve performance equaling that of ML. However, both detectors have different disadvantage. When the transmit antenna number is greater than three antennas, it is difficult to apply the LORD. Therefore, we consider using the sphere decoding together with the LORD. The complexity of the sphere decoding highly depends on the initial radius. In this thesis, we intend to reduce the sphere decoding complexity by using LORD.
75

Continued Study on the Secondary Metabolites and Bioactivities of the Soft Coral Klyxum molle

Lin, Ming-Chang 16 August 2012 (has links)
In order to search for bioactive compounds, we have studied the chemical constituents from the organic extracts of soft coral Klyxum molle. In this study, fifteen eunicellin-type diterpenoids, including eleven new compounds, klymollins K¡VU (1¡V11), along with four known compounds 12¡V15 were isolated. Compounds 16 and 17 were prepared by chemical synthesis. The structures of all compounds were established by spectroscopic methods and comparing the spectral data with known compounds. Compound 5 represents the first eunicellin-type compound with phenylacetyl group. The cytotoxicity of compounds 1¡V17 against K562 (human erythro myeloblastoid leukemia), Molt-4 (human acute lymphoblastic leukemia), and T47D (human breast earcinoma) were determined. Compounds 1, 2, and 3 exhibited weak cytotoxicity against Molt-4 (with ED50 11.52 ¡Ó 2.75, 20.41 ¡Ó 2.92, and 13.11 ¡Ó 3.87 £gg/mL). Compound 5 was found to exhibt significant cytotoxicity toward K562, Molt-4, and T47D (with ED50 4.32 ¡Ó 1.38, 2.36 ¡Ó 0.34, and 4.65 ¡Ó 0.93 £gg/mL). Compound 5 also displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils at 10 £gg/mL (with Inh % 81.56 ¡Ó 3.23, and 89.16 ¡Ó 5.77).
76

Chemical Constituents and Cytotoxicities of the Formosan Soft Corals Sarcophyton crassocaule, Tubipora musica Linneaus and Clavularia inflata

Huang, Mingjae 14 July 2004 (has links)
Chromotographic separations of Formosan soft coral Sarcophyton crassocaule (GN-55) led to the isolations of four diterpenes, sarcophine (1), sarcophytoxide (2), (7R*, 8S*)-dihydroxysarcophytonin A (3), sarcophtonin A (4), one steroid, 17
77

Cytotoxic Constituents from Formosan Soft Coral Clavularia violacea

Chu, Chih-Ju 20 June 2001 (has links)
The methylene chloride and acetone extracts of Formosan soft coral Clavularia violacea (Collected at Green Island) were found to exhibit significant cytotoxicity against P-388, A-549 and HT-29 cancer cell lines. Chromatographic separation let to the isolation of one prostanoid, 1, two cembranoid deterpenes, 2 and 3, one aromadedrane-type sesquiterpene, 4, one neodollabellane diterpene, 5, (+)-curcuphenol, 6 and two sesquiterpene lactones, 7 and 8. Compounds 1, 2, 4, and were new compounds. Compounds 1-5 exhibited significant cytotoxicity against P-388, HT-29 and A-549 cancer cell.
78

Molecular diagnosis of soft tissue tumours

Cheung, Pik-shan. January 2009 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 70-79).
79

OCCURRENCE, SIGNIFICANCE, AND LOCALIZATION OF SOFT-ROTTING BACTERIA IN HEALTHY CUCUMBER TISSUE

Meneley, Jan Craig, 1948- January 1975 (has links)
No description available.
80

Διερεύνηση της φυσικής συμπεριφοράς-ανθεκτικότητας των μαλακών βράχων του Ν. Αχαΐας

Παπαχρήστου, Χριστίνα 25 July 2008 (has links)
Η παρούσα διπλωματική εργασία έχει σαν αντικείμενο μελέτης την αποτίμηση των φυσικών παραμέτρων των μαλακών βράχων.Η περιοχή μελέτης τοποθετείται στο βορειοδυτικό τμήμα της Πελοποννήσου και συγκεκριμένα στο Νομό Αχαΐας. Οι ιδιαιτερότητες των φυσικών χαρακτηριστικών των σχηματισμών αυτών απαιτούν τη συστηματική τους διερεύνηση. Για το λόγο αυτό η μελέτη τους αποκτά μεγάλο ενδιαφέρον. Η εργασία περιλαμβάνει τα παρακάτω στάδια: -Περιγραφή των γεωλογικών συνθηκών σε ευρεία κλίμακα και συγκέντρωση τεκτονικών και σεισμικών στοιχείων της ευρύτερης περιοχής μελέτης. -Λεπτομερής εξέταση, διαχωρισμός και ακριβής προσδιορισμός των θέσεων δειγματοληψίας της περιοχής μελέτης. -Δειγματοληψία από τους σχηματισμούς που απαντώνται στην περιοχή και εκτέλεση εργαστηριακών δοκιμών -Προσδιορισμός των φυσικών παραμέτρων των υπό εξέταση υλικών -Στατιστική επεξεργασία των τιμών των εργαστηριακών δοκιμών με σκοπό την εξαγωγή διαφόρων συμπερασμάτων για τη μηχανική συμπεριφορά των μαλακών βράχων. Η εργασία αυτή εστιάστηκε στη διερεύνηση της αποσαθρωσιμότητας των μαλακών βράχων με εκτέλεση δοκιμών χαλάρωσης (slake durability test). Προς την κατεύθυνση αυτή έγιναν διαδοχικοί κύκλοι της δοκιμής χαλάρωσης (μέχρι 5 κύκλοι) για τη καλύτερη διερεύνηση του φαινομένου. / The aim of this thesis is the study of natural parameters of soft rocks. The region of study is placed in the north-western department of Peloponnese and concretely in the Prefecture Achaia. The particularities of natural characteristics of this shapings require their systematic investigation. For this reason their study acquires big interest. The work includes the following stages: - Description of geological conditions in wide scale and concentration of tectonic and seismic elements of the wider region of study. - Examination and precise determination of places of sampling of region of study. - Sampling from the shapings in the region and implementation of laboratorial trials - Determination of natural parameters of materials under review. - Statistical analysis of prices of laboratorial trials in order to export various conclusions on the mechanic behavior of soft rocks. This work was focused in the investigation of durability of soft rocks with implementation of trials of slake durability test. To this direction they became successive circles of trial of slake durability test (up to 5 circles) for the better investigation of the phenomenon.

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