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排序方式: 共有1516条查询结果,搜索用时 31 毫秒
981.
Alessandra Mirtes Marques Neves Gon?alves Aline Brito de Lima Maria Cristina da Silva Barbosa Luiz Fernando de Camargos Júlia Teixeira de Oliveira Camila de Souza Barbosa José Augusto Ferreira Perez Villar André Carvalho Costa Isabella Viana Gomes da Silva Luciana Maria Silva Fernando de Pilla Varotti Fabio Vieira dos Santos Gustavo Henrique Ribeiro Viana 《Marine drugs》2014,12(8):4361-4378
Cancer continues to be one of the most important health problems worldwide, and the identification of novel drugs and treatments to address this disease is urgent. During recent years, marine organisms have proven to be a promising source of new compounds with action against tumoral cell lines. Here, we describe the synthesis and anticancer activity of eight new 3-alkylpyridine alkaloid (3-APA) analogs in four steps and with good yields. The key step for the synthesis of these compounds is a Williamson etherification under phase-transfer conditions. We investigated the influence of the length of the alkyl chain attached to position 3 of the pyridine ring on the cytotoxicity of these compounds. Biological assays demonstrated that compounds with an alkyl chain of ten carbon atoms (4c and 5c) were the most active against two tumoral cell lines: RKO-AS-45-1 and HeLa. Micronucleus and TUNEL assays showed that both compounds are mutagenic and induce apoptosis. In addition, Compound 5c altered the cellular actin cytoskeleton in RKO-AS-45-1 cells. The results suggest that Compounds 4c and 5c may be novel prototype anticancer agents. 相似文献
982.
Miyahira Roberta Fontanive de Lima Pena Fabíola Fabiano Giovanna Alexandre de Oliveira Lopes Jean Ponte Luis Gustavo Saboia da Cunha Diogo Thimoteo Bezerra Rosangela Maria Neves Antunes Adriane Elisabete Costa 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):233-240
Plant Foods for Human Nutrition - The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The... 相似文献
983.
Ferreira Gabriel Fernandes Pinto Lemos Odair Lacerda Soratto Rogério Peres Perdoná Marcos José 《Precision Agriculture》2022,23(4):1473-1488
Precision Agriculture - The nutritional and productive attributes of Arabica coffee (Coffea arabica L.) can vary spatially within cultivated areas. Precision farming techniques applied to coffee... 相似文献
984.
985.
Silvia Nietsche Aluízio Borém Geraldo Assis de Carvalhos Trazilbo José de Paula Júnor Cláudia Fortes Ferreira Everaldo GonÇalves de Barros Maurilio Alves Moreira 《Euphytica》2001,117(1):77-84
Due to the importance of common bean angular leaf spotin the state of Minas Gerais-Brazil and to the greatvariability of the pathogen, Phaeoisariopsisgriseola, monitoring races becomes an important toolfor breeding programs aiming at genetic resistance.The pathogenic variability of 30 isolates of the P. griseola, collected from various locations in thestate of Minas Gerais, was studied using the followingcommon bean differential series (Don Timóteo,Bolón Bayo, Montcalm, G 5686, Amendoin, G 11796,BAT 332, PAN 72, Cornell 49-242, México 54, Florde Mayo and G 2858). The first trifoliate leaf wasinoculated with a 2 × 104 conidia/mL. Plants weremaintained at 20–22 °C and 95% relativehumidity for 48 hours. Symptom evaluation wasperformed 15 days after inoculation. Thirteen raceswere identified demonstrating the wide geneticvariability of the pathogen in the state of MinasGerais. Race 63.63 was the most virulent, whereas race63.23 was the most frequent (10 of 30 isolates), beingwidely distributed among the regions studied. Thevirulence phenotype indicated that the races studiedbelonged to the Mesoamerican group, which wasconfirmed when the 30 isolates were compared to Andeanand Mesoamerican standards using RAPD markers. 相似文献
986.
Alvaro Vázquez Gabriel González Fernando Ferreira Patrick Moyna Lennart Kenne 《Euphytica》1997,95(2):195-201
Five glycoalkaloids were identified from the aerial parts of wild Solanum commersonii Dun. ex Poir growing in Uruguay and
their structures elucidated mainly by chemical and spectroscopic methods. In addition to the already known commersonine, demissine,
tomatine and dehydrocommersonine, a new glycoalkaloid, identified as δ5-demissine, solanid -5-en-3-O- {β-D-Glcp-(1→2)-[β-D-Xylp-(1→3) ]β-D-Glcp-(1→4)-β-D-Galp } was found. Tomatine and dehydrocommersonine
have not been reported earlier as components of this plant. The glycoalkaloid composition found in the wild plants studied
differ significatively from those described earlier, and have some implications in taxonomy and its use in potato breeding.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
987.
A. Tulmann Neto C.E. de Oliveira Camargo J. Lopes de Castro A.W.P. Ferreira Filho 《Euphytica》2001,120(3):339-343
Seeds from the aluminum sensitive cultivar ‘Anahuac’ were treated by gamma-ray radiation. Twenty eight selected Al+3 tolerant mutants were compared to the original Anahuac and the tolerant wheat cultivars IAC-24 and IAC-60 from 1994 to 1996 in acid (Capão Bonito) and limed (Monte Alegre do Sul and Tatui) soil field trials. Grain yield and agronomic characteristics were analyzed. Twenty six mutant lines yielded higher than the sensitive Anahuac cultivar in the acid soils of Capão Bonito. Under limed soil conditions, the mutants had a similar yield to the original sensitive cultivar. The majority of the mutants were similar in yield to the tolerant cultivars IAC-24 and IAC-60 under both conditions. Some of the mutants showed altered agronomic characteristics but even in these cases this will not limit its utilization. The results indicated that tolerant lines with good characteristics may be obtained from a susceptible cultivar by mutation induction, thus allowing cropping in conditions where Al+3 is a limiting factor. 相似文献
988.
Association of RFLP markers with trait loci affecting clubroot resistance and morphological characters in Brassica oleracea L. 总被引:2,自引:0,他引:2
Summary Resistance to Plasmodiophora brassicae Wor. race 7, the causal agent of the disease clubroot, was examined in an F2 population of a cross between a clubroot resistant broccoli (Brassica oleracea var. italica) and a susceptible cauliflower (B. oleracea var. botrytis). A genetic linkage map was constructed in the same population based on the segregation of 58 dispersed restriction fragment length polymorphism (RFLP) markers. Associations between the inheritance of RFLP marker genotypes and segregation for disease resistance, morphological and maturity characteristics were examined. For each triat examined, several chromosomal regions marked by RFLP probes appeared to contain trait loci, suggesting that each trait was under polygenic control. RFLP marker linkage to a major factor imparting dominance for clubroot resistance from the broccoli parent was observed in this population. Additionally, RFLP marker linkage to an independently segregating factor contributing clubroot resistance from the cauliflower parent was observed, indicating that it should be possible to use RFLP markers to facilitate selection of transgressive segregants having the combined resistance from both parental sources. In some instances, RFLP markers from the same or closely linked chromosomal regions were associated with both clubroot resistance and morphological traits. Analysis of RFLP marker genotypes at linked loci should facilitate the selection of desired disease resistant morphotypes. 相似文献
989.
温度对大叶桃花心木(Swietenia macrophylla King)幼苗叶片的光合影响(英文) 总被引:1,自引:0,他引:1
张成军 Carlos Henrique B.de A.Prado 祖元刚 郭佳秋 Carlos Cesar Ronquim Leonnardo Lopes Ferreira 《林业研究》2003,(2)
本文研究了大叶桃花心木(Swietenia macrophylla King)一年生幼苗在经过夜温处理后的光响应曲线和在饱和光强下的CO2反应曲线。结果表明:在大气CO2浓度下,叶片的最佳光合作用温度在25-31℃之间,而在饱和CO2浓度下为31-35℃。在25℃以下光合速率开始降低,主要是由于羧化效率的降低,而当温度超过31℃时,光合速率下降,是因为羧化效率的降低和呼吸速率的增加。CO2浓度对光合的促进作用在低温下受到抑制,这意味着未来在CO2浓度增高的情况下,高浓度的CO2对热带常绿植物光合的促进在冬天低温情况下表现不十分明显。图4参23。 相似文献
990.
Groups of 14-year-old cacao (Theobroma cacao L.) trees were hand pollinated, pollinated naturally or had their fruits continuously removed. Wilted and non-wilted cherelles (small fruits) were counted every 2 weeks, fallen flowers were counted weekly and mature pods were harvested monthly from 1983 through 1986. Carbohydrate, lipid and protein contents of wilted cherelles, mature pods and flowers were determined. Continuous removal of fruits caused a constant initiation of flowers and a significant increase in flowering intensity compared with the other treatments. The quantity of cherelles in the hand-pollinated trees was significantly greater than in the naturally pollinated trees. However, the number of mature fruits in both treatments was not statistically different because of increased cherelle wilting in the hand-pollinated trees. The continuously depodded trees allocated approximately 8 and 5 times more assimilate to flower production than the hand- and naturally pollinated trees, respectively. The naturally pollinated trees used only about one third as much energy for the production of flowers and wilted cherelles as the hand-pollinated trees, but about 1.4 times more energy than the depodded trees. It is concluded that fruit set in cacao is regulated by assimilate production and that cherelle wilting is the mechanism whereby the tree adjusts production. 相似文献