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21.
Objective: This study used a precise weighing method to assess whether tooth loss was related to nutrient intake in elderly Japanese subjects. Material and methods: Fifty‐seven subjects aged 74 years were randomly selected from a longitudinal interdisciplinary study of ageing. Complete 3‐day food intake data were obtained by a precise weighing method. The dietary intakes of energy and nutrients were calculated based on the Standard Tables of Food Composition in Japan (5th ed.). A clinical evaluation of the number of teeth present was carried out. Multiple regression standardised coefficients for each nutrient was estimated based on a continuous scale adjusted for gender, smoking habits, and educational level. After dividing the subjects into two groups according to the number of teeth present (0–19, 20+), the difference in the intake of nutrients and the amount of food consumed per day was evaluated. Results: The number of teeth present had a significant relationship with the intake of several nutrients. In particular, total protein, animal protein, sodium, vitamin D, vitamin B1, vitamin B6, niacin, and pantothenic acid were significantly associated with the number of teeth present and with the two groups (0–19, 20+). The intake of vegetables and fish, shellfish, and their products was significantly lower among subjects with fewer teeth. Conclusion: This study suggests that there was a significant relationship between nutrient intake, such as minerals and vitamins from food, and tooth loss. 相似文献
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关于费尔干蚌Ferganoconcha 总被引:5,自引:1,他引:5
在追溯费尔干蚌属与科的最初定义及过去学者对此属归科的不同意见后,从我国标本所获对此属铰齿构造了解,说明此属为蚌类化石。认为额尔古纳蚌Arguniella。也是蚌类化石,作者过去将它与费尔干蚌属合并是错误的,同时肯定了原苏联马廷生(G.G.Martinson)对费尔干蚌铰板与铰齿合并的解释。费尔干蚌属的区别特征,在其扁而无壳顶脊的外壳与狭细片状齿无铰板的发育。文末简述了陈金华1999新的不同意见,并作了评论。 相似文献
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Christopher W. Schmidt Ashley Remy Rebecca Van Sessen John Willman Kristin Krueger Rachel Scott Patrick Mahoney Jeremy Beach Jaqueline McKinley Ruggero D'Anastasio Laura Chiu Michele Buzon J. Rocco De Gregory Susan Sheridan Jacqueline Eng James Watson Haagen Klaus Pedro Da-Gloria Jeremy Wilson Abigail Stone Paul Sereno Jessica Droke Rose Perash Christopher Stojanowski Nicholas Herrmann 《American journal of physical anthropology》2019,169(2):207-226
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The thymus and parathyroids are pharyngeal endoderm-derived organs that develop from common organ primordia, which undergo a series of morphological events resulting in separate organs in distinct locations in the embryo. Previous gene expression and functional analyses have suggested a role for BMP4 signaling in early thymus organogenesis. We have used conditional deletion of Bmp4 or Alk3 from the pharyngeal endoderm and/or the surrounding mesenchyme using Foxg1-Cre, Wnt1-Cre or Foxn1-Cre. Deleting Bmp4 from both neural crest cells (NCC) and early endoderm-derived epithelial cells in Foxg1-Cre;Bmp4 conditional mutants resulted in defects in thymus-parathyroid morphogenesis. Defects included reduced condensation of mesenchymal cells around the epithelium, partial absence of the thymic capsule, a delay in thymus and parathyroid separation, and failed or dramatically reduced organ migration. Patterning of the primordia and initial organ differentiation were not affected in any of the mutants. Deleting Bmp4 from NCC-derived mesenchyme or differentiating thymic epithelial cells (TECs) had no effects on thymus-parathyroid development, while loss of Alk3 from either neural crest cells or TECs resulted in only a mild thymic hypoplasia. these results show that the processes of cell specification and morphogenesis during thymus-parathyroid development are independently controlled, and suggest a specific temporal and spatial role for BMP4-mediated epithelial-mesenchymal interactions during early thymus and parathyroid morphogenesis. 相似文献
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拔除阻生智齿患者牙科焦虑的调查及分析 总被引:1,自引:0,他引:1
目的:了解综合医院口腔科拔除阻生智齿患者牙科焦虑的患病情况并进行相关因素分析。方法:采用牙科焦虑一般因素调查表、改良牙科焦虑量表(MDAS)及状态焦虑量表(S-AI)对300例口腔颌面外科门诊的拔除阻生智齿患者进行调查及评定,同时对引起牙科焦虑的相关因素进行分析。结果:拔除阻生智齿患者牙科焦虑的发生率为56.00%,有6项因素对牙科焦虑症的患病率有影响,差异有统计学意义(P<0.05),其中5项因素对MDAS得分影响较大。结论:牙科焦虑在拔除阻生智齿的患者中较普遍,有多种因素影响患者牙科焦虑的程度。 相似文献
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亚洲特有的啮齿类硅藻鼠科自渐新世以来分布于东亚和南亚。现生硅藻鼠类的分布只限于老挝的喀斯特地区。就目前所知,这些具有豪猪型头骨-松鼠型下颌的啮齿类的颊齿都是不同程度的横向双脊齿。时代最早的硅藻鼠类产于巴基斯坦渐新世地层中,其颊齿的双脊齿构造上仍保留齿尖残迹,基本符合双脊齿型牙齿结构。至渐新世末期,硅藻鼠科的牙齿出现分化。中新世及以后硅藻鼠类的化石记录相对较少。分子生物学证据将硅藻鼠类归入Ctenohystrica,这种归属也从始新世梳趾鼠类的臼齿形态上得到一定的支持。除此之外,有关硅藻鼠类的起源问题几乎一无所知。亚洲中始新世的Hydentomys臼齿表现出轻微的双脊型,然而其他方面却与硅藻鼠类不同。另一个具双脊齿的啮齿类Dolosimus(新属)产于江苏中始新世,其具有更为发育的双脊齿,特别是臼齿型下牙。新属的不完整记录及其形态不能解决如下问题:它是否与后来出现的像硅藻鼠类和跃兔类这些具有明显双脊齿型颊齿的啮齿类有亲缘关系,或者只是这种形态发育中没有留下后继者的早期试验品。 相似文献