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排序方式: 共有517条查询结果,搜索用时 203 毫秒
81.
Angelique Flöter Rådestad Atosa Estekizadeh Huanhuan L Cui Ourania N. Kostopoulou Belghis Davoudi Angelica Lindén Hirschberg Joseph Carlson Afsar Rahbar Cecilia Söderberg-Naucler 《Translational oncology》2018,11(6):1292-1300
Human cytomegalovirus (HCMV) has been detected in various types of tumors. We studied the prevalence of HCMV in ovarian cancer and its relation to clinical outcome. Paraffin-embedded tissues obtained prospectively from 45 patients with ovarian cancer and 30 patients with benign ovarian cystadenoma were analyzed for expression of HCMV immediate-early protein (IE) and HCMV tegument protein (pp65) by immunohistochemistry. Plasma was analyzed for HCMV serology. HCMV-IgG levels were higher in patients with ovarian cancer or benign cystadenoma than in age-matched controls (P?=?.002, P?<?.0001, respectively). HCMV IgM was detected in 12% of ovarian cancer patients and 3% of patients with benign tumors but was absent in controls. In patients with ovarian cancer, higher IgG levels were associated with better outcomes (P?=?.04). Extensive HCMV-IE protein expression was detected in 75% of ovarian cancers and 26% of benign tumors; pp65 was detected in 67% of ovarian cancers and 14% of benign tumors. A higher grade of HCMV infection was associated with higher stage of disease. Extensive HCMV-pp65 expression was associated with shorter median overall survival than focal expression (39 versus 42.5?months, P?=?.03). At study closure, 58% of ovarian cancer patients with focal pp65 expression were alive versus 27% of patients with extensive pp65 expression (P?=?.03). Thus, HCMV proteins are detected at different levels in ovarian tumors and benign cystadenomas. Ovarian cancer patients with focal HCMV-pp65 expression in their tumors and high IgG levels against HCMV lived longer, highlighting a need for in-depth studies of the oncomodulatory role of HCMV in ovarian cancer. 相似文献
82.
Ferdinand Bohlmann Jasmin Jakupovic Angelica Schuster Robert M. King Harold Robinson 《Phytochemistry》1984,23(7):1445-1448
The aerial parts of Flourensia macrophylla afforded, in addition to compounds similar to those from other Flourensia species, four new eudesman 相似文献
83.
Ferdinand Bohlmann Ngo Le Van Thi Van Cuong Pham Jasmin Jacupovic Angelica Schuster Volker Zabel William H. Watson 《Phytochemistry》1979,18(11):1831-1834
The investigation of several Berkheya species afforded in addition to already known compounds three unusual sesquiterpene hydrocarbons. Together with modhephene and isocomene, a new one is present, its structure being elucidated by spectroscopic methods and by some chemical transformations. All 18 species investigated contain the typical thiophene derivatives, isolated earlier; the patterns of compounds present divide the species into two groups. 相似文献
84.
85.
Chiara Beltramo Nadia Valentini Ezio Portis Daniela Torello Marinoni Paolo Boccacci Maria Angelica Sandoval Prando Roberto Botta 《Molecular breeding : new strategies in plant improvement》2016,36(3):27
The European hazelnut (Corylus avellana L.) is the most economically important nut species in the Betulaceae family. Despite the need for new improved hazelnut cultivars, few breeding programs are carried out because of the large plant size, the long lifecycle of the plant, and the expense and time required. To date, there are no reports of maps with quantitative trait loci (QTL) in hazelnut. Our objective in the present study was to identify QTL associated with vegetative traits to allow marker-assisted selection (MAS). An F1 progeny (275 plants) of Tonda Gentile delle Langhe × Merveille de Bollwiller obtained in 2009 was used to develop a QTL linkage map for vigour, sucker habit, and time of bud burst, after three years of observations. A set of 163 plants were analysed with 152 microsatellite markers. A map of 11 linkage groups was obtained, covering 663.1 cM, and 15 QTLs were identified and mapped for the traits examined. Of them, 10 were ‘major’ QTL, including a stably expressed region on LG_02 for leaf bud burst. At least one major QTL for each year underlies the variation in each trait and a clustering of QTL for trunk circumference and suckers/trunk circumference ratio with high inter-trait correlations was observed on LG_05, suggesting a single pleiotropic locus. This research represents an initial step in the future identification of chromosomal regions carrying genes of interest, important for breeding programs and MAS. 相似文献
86.
Thaís C. Lima Rodrigo Lucarini Angelica C. Volpe Carolina Q.J. de Andrade Alice M.P. Souza Patricia M. Pauletti Ana H. Januário Guilherme V. Símaro Jairo K. Bastos Wilson R. Cunha Alexandre Borges Rosangela da Silva Laurentiz Valéria A. Conforti Renato L.T. Parreira Carly H.G. Borges Giovanni F. Caramori Karla F. Andriani Márcio L.A. e Silva 《Bioorganic & medicinal chemistry letters》2017,27(2):176-179
(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK. 相似文献
87.
88.
Crottini A Marotta R Barbuto M Casiraghi M Ferraguti M 《Molecular phylogenetics and evolution》2008,48(3):1189-1203
Tubifex tubifex Müller, 1774 is a cosmopolitan freshwater tubificid widely used as a model in ecotoxicology, population dynamics and developmental biology. It is traditionally recognized as a polytypic species and in Lambro River (Milano, Northern Italy) it occurs in two of the three recognized forms, named "tubifex" and "blanchardi", alternatively considered as ecological forms or distinct species. To investigate the genetic differentiation of the populations occurring in the Lambro River we sequenced a fragment of the 16S rDNA mitochondrial gene. T. blanchardi, characterized by a low genetic diversity, was genetically segregated from the other sympatric T. tubifex. The ancestral state reconstruction was used to define the morphological traits that support its distinctness. On the contrary, the other T. tubifex from the Lambro community, although morphologically indistinguishable, revealed an astonishing degree of genetic variability, both between and within the three identified clades that proved to be genetically isolated. Using samples from the mixed Lambro River community and from other countries around the world we present an overview of the species complex' 16S rDNA variability. Our results show that the genetic variability did not sensibly increase widening the data set, suggesting that the Lambro River populations meet the species' worldwide genetic variability. 相似文献
89.
The non-indigenous perennial grass, Arundo donax, is an aggressive invader of riparian areas throughout California and many sub-tropical regions of the world, and is hypothesized to provide poorer quality habitat for native wildlife in riparian systems. We sampled aerial and ground-dwelling insects and other terrestrial arthropods associated with Arundo, native willow vegetation (Salix spp.), and mixtures of the two vegetation types during two seasons to determine how Arundo influences invertebrate composition in a low gradient stream in central California. The total number of organisms, total biomass and taxonomic richness of aerial invertebrates associated with native vegetation was approximately twice that associated with Arundo vegetation, while mixed vegetation supported intermediate arthropod levels. Shannon-Weaver (Weiner) diversity associated with native vegetation stands was also higher than that of Arundo vegetation. Ground-dwelling assemblages did not show differences as great as aerial assemblages which are more critical to foraging avian species. These results indicate that vegetation type is a significant factor reducing the abundance and diversity of invertebrates in this, and presumably in many other riparian ecosystems where this invasive species has become a dominant component. Arundo invasion changes the vegetation structure of riparian zones and in turn, may increasingly jeopardize its habitat value for birds and other wildlife whose diets are largely composed of insects found in native riparian vegetation. 相似文献
90.
Mar Perez†† Ismael Santa-Maria Elena Gomez de Barreda Xiongwei Zhu† Raquel Cuadros Jose Roman Cabrero‡‡‡ Francisco Sanchez-Madrid‡‡‡ Hana N. Dawson§ Michael P. Vitek§ George Perry†¶ Mark A. Smith† Jesus Avila 《Journal of neurochemistry》2009,109(6):1756-1766
Analysis of brain microtubule protein from patients with Alzheimer's disease showed decreased alpha tubulin levels along with increased acetylation of the alpha tubulin subunit, mainly in those microtubules from neurons containing neurofibrillary tau pathology. To determine the relationship of tau protein and increased tubulin acetylation, we studied the effect of tau on the acetylation-deacetylation of tubulin. Our results indicate that tau binds to the tubulin-deacetylase, histone deacetylase 6 (HDAC6), decreasing its activity with a consequent increase in tubulin acetylation. As expected, increased acetylation was also found in tubulin from wild-type mice compared with tubulin from mice lacking tau because of the tau-mediated inhibition of the deacetylase. In addition, we found that an excess of tau protein, as a HDAC6 inhibitor, prevents induction of autophagy by inhibiting proteasome function. 相似文献