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1.
Margherita Ratti Andrea Lampis Jens C. Hahne Rodolfo Passalacqua Nicola Valeri 《Cellular and molecular life sciences : CMLS》2018,75(22):4151-4162
Gastric cancer is one of the most aggressive malignancies, with limited treatment options in both locally advanced and metastatic setting, resulting in poor prognosis. Based on genomic characterization, stomach tumour has recently been described as a heterogeneous disease composed by different subtypes, each of them with peculiar molecular aspects and specific clinical behaviour. With an incidence of 22% among all western gastric tumour cases, stomach cancer with microsatellite instability was identified as one of these subgroups. Retrospective studies and limited prospective trials reported differences between gastric cancers with microsatellite stability and those with instability, mainly concerning clinical and pathological features, but also in regard to immunological microenvironment, correlation with prognostic value, and responses to treatment. In particular, gastric cancer with microsatellite instability constitutes a small but relevant subgroup associated with older age, female sex, distal stomach location, and lower number of lymph-node metastases. Emerging data attribute to microsatellite instability status a favourable prognostic meaning, whereas the poor outcomes reported after perioperative chemotherapy administration suggest a detrimental role of cytotoxic drugs in this gastric cancer subgroup. The strong immunogenicity and the widespread expression of immune-checkpoint ligands make microsatellite instability subtype more vulnerable to immunotherapeutic approach, e.g., with anti-PD-L1 and anti-CTLA4 antibodies. Since gastric cancer with microsatellite instability shows specific features and clinical behaviour not overlapping with microsatellite stable disease, microsatellite instability test might be suitable for inclusion in a diagnostic setting for all tumour stages to guarantee the most targeted and effective treatment to every patient. 相似文献
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Paul D. Taylor Silviu O. Martha Dennis P. Gordon 《Journal of Natural History》2018,52(25-26):1657-1721
Genera assigned to the cheilostome bryozoan family Onychocellidae are revised based on the skeletal morphology of the type species and, when possible, the type material of these species. All genera are illustrated using scanning electron micrographs, some for the first time. Onychocellidae, which ranges from the Cenomanian stage of the Cretaceous to the Recent, has been a particularly troublesome family because of poorly defined generic concepts correlating at least in part with a paucity of morphological characters. Thirty-five genera are described in this review. Of these, two are recognised as subjective synonyms of other onychocellid genera (Rhebasia and Semieschara), one cannot be sufficiently characterised from the type material (Collura), and two are new: Aechmellina gen. nov. (type species Aechmella falcifera) and Kamilocella gen. nov. (type species Eschara latilabris). A neotype is chosen for Rhagasostoma hexagonum, the type species of Rhagasostoma. A key is provided to assist in the identification of onychocellid genera. Phylogenetic relationships between genera remain obscure and are unlikely to be fully resolved based on skeletal morphology alone. The family as an entity is loosely circumscribed and almost certainly paraphyletic, containing stem genera of other anascan familes such as Lunulitidae, Coscinopleuridae and Aspidostomatidae.
www.zoobank.org/urn:lsid:org:pub:63A31AD2-F049-42CB-A45B-557014DC286E 相似文献
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系统地总结和介绍了我国高性能计算机,包括“银河”系列巨型机、“曙光”系列巨型机、“神威”系列巨型机、“深腾”系列巨型机以及“深超”系列巨型机的开发研制以及应用情况。 相似文献
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董文伟 《科技情报开发与经济》2004,14(6):296-297
以具体工程为例,介绍了建筑物地基处理的设计、施工中遵循的原则,施工中遇到特殊情况时采取的处理方法和必要的检测方法,对几种桩基的设计要求、施工工艺及过程、质量控制等情况进行了简单阐述。 相似文献
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Ten-day treatment with nicotine (5, 25 or 50 micrograms/ml drinking water) dose-dependently intensified gastric ulceration induced by cold-restraint, and emptying rate. Stomach contractions produced by graded doses of bethanechol i.v. were elevated further by nicotine treatment. It is suggested that chronic nicotine administration produces hypersensitivity of the gastric muscarinic receptors; stomach hypermotility contributes to the ulcer-worsening action of the alkaloid. 相似文献
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新的、高密度树木种植正在给林业生物技术带来迅速的变化。但是如果不能克服生态风险和经济障碍.这些新的方法或许永远也无法使用—— 相似文献
10.
The Shwachman-Bodian-Diamond syndrome protein mediates translational activation of ribosomes in yeast 总被引:1,自引:0,他引:1
Menne TF Goyenechea B Sánchez-Puig N Wong CC Tonkin LM Ancliff PJ Brost RL Costanzo M Boone C Warren AJ 《Nature genetics》2007,39(4):486-495
The autosomal recessive disorder Shwachman-Diamond syndrome, characterized by bone marrow failure and leukemia predisposition, is caused by deficiency of the highly conserved Shwachman-Bodian-Diamond syndrome (SBDS) protein. Here, we identify the function of the yeast SBDS ortholog Sdo1, showing that it is critical for the release and recycling of the nucleolar shuttling factor Tif6 from pre-60S ribosomes, a key step in 60S maturation and translational activation of ribosomes. Using genome-wide synthetic genetic array mapping, we identified multiple TIF6 gain-of-function alleles that suppressed the pre-60S nuclear export defects and cytoplasmic mislocalization of Tif6 observed in sdo1Delta cells. Sdo1 appears to function within a pathway containing elongation factor-like 1, and together they control translational activation of ribosomes. Thus, our data link defective late 60S ribosomal subunit maturation to an inherited bone marrow failure syndrome associated with leukemia predisposition. 相似文献