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141.

Background  

Immunotherapy is emerging as a major player in the current standard of care for aggressive cancers such as non-small cell lung cancer (NSCLC). The Newcastle disease virus with its tumor-specific replicative and oncolytic abilities is a promising immunotherapeutic candidate. A DNA vaccine expressing the major immunogenic hemagglutinin-neuraminidase (HN) protein of this virus has shown promising results as an immunotherapeutic agent.  相似文献   
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The notochord and notochordal sheath of 10 adult amphioxus were investigated ultrastructurally and histochemically. The notochord in amphioxus consists of parallel notochordal cells (plates) and each plate consists of parallel thicker and thinner fibrils and numerous profiles of smooth endoplasmic reticulum situated just beneath the cell membrane. Histochemical staining shows that the notochordal plates resemble neither the connective tissue notochordal sheath nor the typical muscular structure myotomes. The notochordal sheath has a complex three-layered organization with the outer, middle and inner layer The outer and middle layer are composed of collagen fibers of different thickness and course, that correspond to collagen type I and collagen type III in vertebrates, respectively, and the inner layer is amorphous, resembles basal lamina, and is closely attached to the notochord by hemidesmosome junctions. These results confirm the presence of collagen fibers and absence of elastic fibers in amphioxus.  相似文献   
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A novel series of steroidal compounds were designed and synthesized with various phosphorus-containing groups on the 17beta-side chain as progesterone receptor antagonists. The structure-activity relationships of these compounds are discussed. Selected compounds were tested in an rat progesterone-sensitive assay. Some of these compounds are more potent than mifepristone, with a better selectivity profile in differentiating progesterone receptor from glucocorticoid receptor.  相似文献   
147.
The inactive X chromosome of female mammals displays several properties of heterochromatin including late replication, histone H4 hypoacetylation, histone H3 hypomethylation at lysine-4, and methylated CpG islands. We show that cre-Lox-mediated excision of 21 kb from both Xist alleles in female mouse fibroblasts led to the appearance of two histone modifications throughout the inactive X chromosome usually associated with euchromatin: histone H4 acetylation and histone H3 lysine-4 methylation. Despite these euchromatic properties, the inactive X chromosome was replicated even later in S phase than in wild-type female cells. Homozygosity for the deletion also caused regions of the active X chromosome that are associated with very high concentrations of LINE-1 elements to be replicated very late in S phase. Extreme late replication is a property of fragile sites and the 21-kb deletions destabilized the DNA of both X chromosomes, leading to deletions and translocations. This was accompanied by the phosphorylation of p53 at serine-15, an event that occurs in response to DNA damage, and the accumulation of gamma-H2AX, a histone involved in DNA repair, on the X chromosome. The Xist locus therefore maintains the DNA stability of both X chromosomes.  相似文献   
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The effects of corticosterone (CORT) administration on the development of muscular tissues of broiler chickens (Gallus gallus domesticus) fed with diets differing in lipid content were investigated. The experimental chickens were given one of two experimental diets: high lipid diet (9.9% crude fat) or control diet, from 21 d of age. At 28 d of age, half of the chickens in each dietary treatment were exposed to CORT treatment, supplemented with 30 mg CORT/kg diet for 12 days, while the other half continued to consume the former diet. The zootechnical parameters were recorded at 21, 28, 35 and 39 d, and a blood sample was obtained from 8 birds of each group, respectively. The growth performance of broiler chickens was significantly depressed by CORT administration, but not by dietary treatment. Corticosterone treatment resulted in enhanced energy expenditure. The results indicate that the development of breast muscle was more susceptible to stress mimicked by CORT administration. The results suggest that corticosterone administration enhanced hepatic fatty acid synthesis and resulted in the redistribution of energy to abdominal store from peripheral tissues. Diet rich in lipid content was favorable to the central fat deposit in stressed broiler chickens.  相似文献   
149.
A major cytoskeletal and extracellular matrix proteins of the amphioxus notochordal cells and sheath were detected by immunohistochemical techniques. The three-layered amphioxus notochordal sheath strongly expressed fish collagen type I in its outer and middle layers, while in the innermost layer expression did not occur. The amphioxus notochordal sheath was reactive to applied anti-human antibodies for intermediate filament proteins such as cytokeratins, desmin and vimentin, as well as to microtubule components (beta-tubulin), particularly in the area close to the epipharyngeal groove. Alpha-smooth muscle actin was expressed in some notochordal cells and in the area of the notochordal attachment to the sheath. Thus muscular nature of notochordal cells was shown by immunohistochemistry in tissue section. Our results confirm that genes encoding intermediate filament proteins, microtubules and microfilaments are highly conserved during evolution. Collagen type I was proven to be the key extracellular matrix protein that forms the amphioxus notochordal sheath.  相似文献   
150.
A semidwarf line of Indica rice, Xinguiai, was derived from the progeny of a cross between the double dwarf mutant Xinguiaishuangai and the wild-type variety Nanjing 6. The semidwarf phenotype was controlled by the semidwarf gene, sdg. The second sheath and shoot elongation responses of the dwarf mutant to exogenous gibberellin (GA3) showed that sdg was insensitive to gibberellin (GA), and its endogenous GAs content was higher than that in wild-type cultivars. The SDG gene was cloned by a map-based cloning method and sequencing analysis revealed that the coding region of sdg had a single nucleotide substitution resulting in a single amino acid change from alanine to threonine. A cleaved amplified polymorphic sequence marker was designed according to sequences from mutant and wild-type materials. This sequence marker could be used to distinguish wild types and mutants, and thus, could be used for molecular marker-assisted selection. The dwarf phenotype of the sdg mutant was restored to a normal phenotype by introducing the wild-type SDG gene. Rice transformation experiments and GUS staining demonstrated that the SDG gene was predominantly expressed in vegetative organs.  相似文献   
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