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41.
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Three new steroids, petasitosterones A and B (1 and 2) and a spirosteroid petasitosterone C (3), along with eight known steroids (4–11), were isolated from a Formosan marine soft coral Umbellulifera petasites. The structures of these compounds were elucidated by extensive spectroscopic analysis and comparison of spectroscopic data with those reported. Compound 3 is a marine steroid with a rarely found A/B spiro[4,5]decane ring system. Compounds 1–3 and 5 displayed inhibitory activity against the proliferation of a limited panel of cancer cell lines, whereas 2 and 5 exhibited significant anti-inflammatory activity to inhibit nitric oxide (NO) production. The inhibitory activities for superoxide anion generation and elastase release of compounds 1–11 were also examined to evaluate the anti-inflammatory potential, and 2–4 were shown to exhibit significant activities.  相似文献   
43.
Two new cubitanoids, nanoculones A and B (1 and 2), and three new cembranoids, nanolobols A–C (3–5), as well as six known compounds, calyculone I (6), sinulariuol A (7), sinulariols C, D, H, and J (8–11), were isolated from the soft coral Sinularia nanolobata, collected off the coast of the eastern region of Taiwan. Their structures were elucidated on the basis of extensive spectroscopic analysis. Cytotoxicity of compounds 1–11 was evaluated. The nitric oxide (NO) inhibitory activity of selected compounds was further measured by assay of lipopolysaccharide (LPS)-stimulated NO production in activated RAW264.7 cells. The results showed that none of 1–11 exhibited cytotoxicity against the tested cancer cell lines, whereas compound 8 was found to significantly reduce NO production.  相似文献   
44.
A polyoxygenated and halogenated labdane, spongianol (1); a polyoxygenated steroid, 3β,5α,9α-trihydroxy-24S-ethylcholest-7-en-6-one (2); a rare seven-membered lactone B ring, (22E,24S)-ergosta-7,22-dien-3β,5α-diol-6,5-olide (3); and an α,β-unsaturated fatty acid, (Z)-3-methyl-9-oxodec-2-enoic acid (4) as well as five known compounds, 10-hydroxykahukuene B (5), pacifenol (6), dysidamide (7), 7,7,7-trichloro-3-hydroxy-2,2,6-trimethyl-4-(4,4,4-trichloro-3-methyl-1-oxobu-tylamino)-heptanoic acid methyl ester (8), and the primary metabolite 2’-deoxynucleoside thymidine (9), have been isolated from the Red Sea sponge Spongia sp. The stereoisomer of 3 was discovered in Ganoderma resinaceum, and metabolites 5 and 6, isolated previously from red algae, were characterized unprecedentedly in the sponge. Compounds 7 and 8 have not been found before in the genus Spongia. Compounds 1–9 were also assayed for cytotoxicity as well as antibacterial and anti-inflammatory activities.  相似文献   
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The objective of the project was to determine the effects of tea (Camellia sinensis) leaf beverage consumption on the apparent utilization of niacin, thiamin, and protein in human subjects. During two randomly arranged experimental periods of 14 days each, 10 adult female human subjects were fed a constant (same foods each day), measured, laboratory-controlled diet. Tea was fed during one period while no tea was allowed during the other period. A dehydrated black tea infusion product (instant tea, 8 g/subject/day/dry weight basis) was used which subjects were allowed to dilute in water. Subjects made complete collections of urine and stools. Fasting blood samples were drawn at the end of each experimental period. No effects on protein status were demonstrated. Urinary thiamin losses were depressed with the use of tea but niacin losses were increased. Blood serum concentrations of thiamin diphosphate also were depressed during the tea drinking period as compared to values during the non-tea period. No significant effect on blood serum levels of nicotinaminde or N-methylnicotinamine were found but values tended to be lower during the tea than the non-tea period. These results suggest that tea consumption inhibits the utilization of thiamin. However, niacin availability was unaffected by tea drinking. Because of the decreased availability of thiamin, the need for niacin was depressed which caused a greater than expected urinary loss of this vitamin.Published as University of Nebraska Journal Articles Series No. 9496. Supported by University of Nebraska Agricultural Research Division Project 91-031 and U.S.D.A. C.S.R.S. Regional Project W-143.  相似文献   
47.
Two novel diterpenoids, sinularbols A (1) and B (2), which were found to possess a new carbon skeleton were isolated from the soft coral Sinularia arborea. The structures of compounds 1 and 2 were elucidated by spectroscopic methods and 2 displayed a moderately inhibitory effect on the generation of superoxide anion by human neutrophils.  相似文献   
48.
Three new eunicellin-type diterpenoids, krempfielins N–P (1–3), were isolated from a Taiwanese soft coral Cladiella krempfi. The structures of the new metabolites were elucidated by extensive spectroscopic analysis and by comparison with spectroscopic data of related known compounds. Compound 3 exhibited activity to inhibit superoxide anion generation. Both 1 and3, in particular 1, were shown to display significant anti-inflammatory activity by inhibiting the elastase release in FMLP/CB-induced human neutrophils.  相似文献   
49.
Five new eunicellin-based diterpenoids, klymollins T–X (1–5), along with two known compounds (6 and 7) have been isolated from the soft coral Klyxum molle. The structures of these new metabolites were elucidated by extensive spectroscopic analysis and by comparison with related known compounds. Compound 5 was found to exert significant in vitro anti-inflammatory activity against LPS-stimulated RAW264.7 macrophage cells. Furthermore, compounds 4 and 7 were shown to exhibit cytotoxicity against a limited panel of human cancer cell lines.  相似文献   
50.
春玉米密植定额和种植方式研究   总被引:2,自引:0,他引:2  
本文综合分析了淮阴地区历年来有关春玉米密植定额和种植方式的试验资料。在密植定额问题上,研究了密度与产量、品种、生产水平间的关系,并从田间小气候、植株生长发育、光能利用、群体与个体关系等方面探索了密植增产的原因;在种植方式问题上,比较了不同生产水平和不同密度下,宽窄行和等行距的效果,并从根系发育、植株性状、田间小气候、光能利用等方面分析了宽窄行减产的原因。  相似文献   
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