医疗纠纷民事诉讼三题

医疗纠纷本质上是民事纠纷,我国医疗纠纷的解决机制是通过民事诉讼的途径。但当下我国医疗纠纷诉讼存在颇多争议。通过分析医疗纠纷案件中存在的三个常见问题,探讨我国医疗纠纷的解决之道。     

杉科化石植物角质层的研究

化石角质层是地质史上真正生活过的植物活体上的原物，其表皮细胞和气孔的特征以及气孔的分布与排列可作为杉科植物属种分类的依据．本文简要讨论了角质层在杉科化石植物研究上的重要性．     

论中介语石化现象

从中介语的概念、分析方法及产生原因等方面介绍了中介语石化现象,并总结了一些防止或延缓中介语石化的方法,以期对语言教学有所增益.     

Fossil that fills a critical gap in avian evolution

Despite the discoveries of well-preserved Mesozoic birds, a key part of avian evolution, close to the radiation of all living birds (Aves), remains poorly represented. Here we report on a new taxon from the Late Cretaceous locality of Ukhaa Tolgod, Mongolia, that offers insight into this critically unsampled period. Apsaravis and the controversial alvarezsaurids are the only avialan taxa known from the continental deposits at Ukhaa Tolgod, which have produced hundreds of fossil mammals, lizards and other small dinosaurs. The new taxon, Apsaravis ukhaana, is the best-preserved specimen of a Mesozoic ornithurine bird discovered in over a century. It provides data important for assessing morphological evolution across Avialae, with implications for, first, the monophyly of Enantiornithes and Sauriurae; second, the proposition that the Mesozoic sister taxa of extant birds, as part of an 'ecological bottleneck', inhabited exclusively near-shore and marine environments; and third, the evolution of flight after its origin.     

化石中氨基酸的成岩作用

分析了两广地区一些第四纪骨和牙化石的氨基酸含量、外消旋程度，探讨了化石中氨基酸的成岩变化特征，阐述了化石中残留蛋白的降解导致氨基酸外消旋速度的变化，并使其在外消旋反应的后期偏离线性动力学