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11.
山东平邑盆地固城组、卞桥组共发现介形类化石21属21种4比较种13未定种,本文记述了其中的17属16种4比较种9未定种。卞桥组一段下部的介形类可称为Talicypridea reticulata-Mongolocypris longa-Frambocythere fangjiaheensis介形类动物群,含化石地层的时代被确认为晚白垩世最晚期,即马斯特里赫特期的晚期。该动物群的发现,为平邑盆地白垩系/古近系界线的确定提供了十分重要的依据。  相似文献   
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Lipid droplets (LDs) are ubiquitous cellular organelles for lipid storage which are composed of a neutral lipid core bounded by a protein decorated phospholipid monolayer. Although lipid storage is their most obvious function, LDs are far from inert as they participate in maintaining lipid homeostasis through lipid synthesis, metabolism, and transportation. Furthermore, they are involved in cell signaling and other molecular events closely associated with human disease such as dyslipidemia, obesity, lipodystrophy, diabetes, fatty liver, atherosclerosis, and others. The last decade has seen a great increase in the attention paid to LD biology. Regardless, many fundamental features of LD biology remain obscure. In this review, we will discuss key aspects of LD biology including their biogenesis, growth and regression. We will also summarize the current knowledge about the role LDs play in human disease, especially from the perspective of the dynamics of the associated proteins. This article is part of a Special issue entitled Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers.  相似文献   
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The Meishucun stage is the prelude in decipher-ing the Cambrian Explosion. In this prominent stage, rapid radioactive evolution and body-plan innovation have taken place and different associations of organism have been shaped. In this paper we report several 3D-preserved rare star-like fossils with finely preserved soft tissues which were recovered from the Kuanchuanpu Member of the Dengying Formation in South Shaanxi, China in 2003. By studying on functional morphology and analogy with mouthpart of Punctatus, there are evidences that this star-like organism approaches the coelenterates in systematic classification and the centre of star-like organism is its mouth. The appearance of coelenterates marks the real beginning of metazoan evolution. Therefore, it has the prominent position in the origin and evolutionary history of organisms. Perhaps the star-like organism represents the early types of coelenterate with original tentacles. These new materials provide new evidence for the origin, evolution and the functional evolution of the metazoan during the early stage of the Cambrian Explosion.  相似文献   
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Depression is a complex psychiatric disturbance involving many environmental, genetic, and epigenetic factors. Until now, genetic, and non-genetic studies are still on the way to understanding the complex mechanism of this disease, and there are still many questions that have not yet been answered. Depression includes a large spectrum of heterogeneous symptoms correlated to the deficit of a range of psychological, cognitive, and emotional processes, and it affects various age groups. It is classified into several types according to the severity of symptoms, time of occurrence, and time. Following the World Health Organization (WHO), depression attacks near 350 million persons globally. Several factors overlap in causing depression, including genetic and epigenetic factors, environmental conditions, various stresses, lack of some nutrients to which people are exposed, and excessive stress and abuse in childhood. This study included conducting surveys on depression and new treatment trends based on epigenetic factors associated with the occurrence of the disease. Epigenetic factors provide a completely novel dimension to therapeutic approaches as most diseases are not monogenic, and it is likely that the environment has a significant contribution. Epigenetic inheritance is included in many mental and psychiatric disorders such as depression. In general, epigenetic modifications could be summarized in 3 major points: DNA methylation, histone modification, and non-mediated regulation of RNA (ncRNA). This study also describes some genes associated with one of the depressive disorders using bioinformatics tools and gene bank and had the genes: SLC6A4, COMT, TPH2, FKBP5, MDD1, HTR2A, and MDD2. As in this study, the awareness of Saudi society about depression and its genetic and non-genetic causes was estimated. The results showed that an encouraging percentage of more than half of the research sample possessed correct information about this disorder.  相似文献   
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Abstract

North Korea and the Soviet Union delimited their land and sea boundaries in two treaties, signed in 1985 and 1986. A warming bilateral relationship, joint plans to develop an economic zone near the Tumen River land boundary, and the desire to exploit marine resources, especially offshore oil, probably accelerated the negotiations. The two countries’ straight baseline claims affected the bearing of the negotiated boundaries. The territorial sea boundary may have given half‐effect to the natural coastline, and inexplicably, its terminus falls short of extending a full 12 nautical miles from the respective straight baseline claims. The 1986 continental shelf/exclusive economic zone boundary reflects the baselines and appears to delimit the South Korea—Soviet Union continental shelf, as well as the tri‐point with Japan. It ignores the presence of Liancourt Rocks (Takeshima/Tok‐do), islets disputed between Japan and South Korea. Neither South Korea nor Japan has publicly commented on the treaties.  相似文献   
18.
南极维多利亚地南部Carapace Nunatak中侏罗世孢粉植物群   总被引:3,自引:0,他引:3  
尚玉珂 《古生物学报》1997,36(2):170-186
南极维多利亚地的费拉群孢粉植物时代一直被认为是早株罗世、从维多利亚地南部Carapace Nunatak费拉群火山岩夹杂中发现的数量丰富,类型多样的孢粉化石。可与澳大利亚西部、阿根廷、印度及巴基斯孢粉植物群比较,推断费拉群时代应为中侏罗世,并很可能为中侏罗世早期。这一结论得到从相同地点获得的叶肢介化石的佐证。根据孢子花粉化石的可能植物亲缘关系,推断中侏罗世早期维多利亚地南部以掌鳞杉科植物较繁盛,并  相似文献   
19.
本文系统研究了广西南垌早石炭世巴平组下段丰富的牙形刺,识别出Siphonodella duplicata,S.cooperi,S.obosoleta,S.quadruplicata,S.lobata,S.crenulata,S.sandbergi,S.eurylobata,S.isosticha,Gnathodus delicatus等重要的带化石。首次报道和描述了产自Siphonodella crenulata带下部牙形刺新材料,其中确立一新种:Siphonodella nandongensis sp.nov.Li;一新未定种:Siphonodellasp.nov.A;且修订了Siphonodella trirostrata Druce(1969)的含义。依据上述牙形刺:Siphonodella nandongensis sp.nov.Li;Siphonodellasp.nov.A和Siphonodella trirostrata Druce(1969)发育特征,认为Siphonodella nandongensis sp.nov.Li与Siphonodella sexplicata;Siphonodella sp.nov.A与Siphonodella quadruplicata(Branson et Mehl);Siphonodella trirostrata Druce(1969)与Siphonodella sandbergi Klapper演化关系密切,并确定所描述的化石新材料的层位是Siphonodella crenulata带下部,地质时代为早石炭世早期,为进一步精细地层划分提供了翔实资料。  相似文献   
20.
The Meishucun stage is the prelude in deciphering the Cambrian Explosion. In this prominent stage, rapid radioactive evolution and body-plan innovation have taken place and different associations of organism have been shaped. In this paper we report several 3D-preserved rare star-like fossils with finely preserved soft tissues which were recovered from the Kuanchuanpu Member of the Dengying Formation in South Shaanxi, China in 2003. By studying on functional morphology and analogy with mouthpart of Punctatus, there are evidences that this star-like organism approaches the coelenterates in systematic classification and the centre of star-like organism is its mouth. The appearance of coelenterates marks the real beginning of metazoan evolution. Therefore, it has the prominent position in the origin and evolutionary history of organisms. Perhaps the star-like organism represents the early types of coelenterate with original tentacles. These new materials provide new evidence for the origin, evolution and the functional evolution of the metazoan during the early stage of the Cambrian Explosion. __________ Translated from Acta Micropalaeontologica Sinica, 2006, 23(1): 62–69 [译自: 微体古生物学报]  相似文献   
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