检索结果-南通市图书馆

Acta Geologica Sinica(English Edition) 2024年第2期98卷 303-310页

作者： ZHANG Honggang YIN Yalei PEI Rui ZHOU Changfu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266570China College of Paleontology Shenyang Normal UniversityShenyang 110034China Key Laboratory of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang 110034China Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China

Three eusauropod teeth(SDUST-V1064,PMOL-AD00176,PMOL-ADt0005)are reported from the Lower Cretaceous Yixian Formation of Ningcheng,southeastern Inner Mongolia,*** of them(SDUST-V1064,PMOL-AD00176)are assigned to early-diverging titanosauriforms in having slightly mesiodistal expansion at the base of the tooth crown,a slenderness index value>2.0 and<4.0,and D-shaped cross ***,SDUST-V1064 and PMOL-AD00176 are referred as an Euhelopus-like titanosauriform on the basis of having a sub-circular boss on the lingual surface and an asymmetrical crown-root margin which slants apically,*** scan data of SDUST-V1064 reveals new dental information of early-diverging titanosauriforms,for example,the enamel on the labial side thicker than that on the lingual side,an enamel/dentine ratio of 0.26 and a boss present on the lingual side of the dentine of the crown.

关键词： teeth Titanosauriformes Lower Cretaceous Yixian Formation Ningcheng

Comparison of the Anatomy and Adaptability of Reconstructed teeth with Natural teeth:An Innovative Approach in Forensic Dentistry

在线全文

学校读者我要写书评

暂无评论

Journal of Forensic Science and Medicine 2024年第1期10卷 47-54页

作者： Supraja S P M Tejaswi Ravikanth Manyam Mohan Kumar Pasupuleti Swetha P Ramesh Kumar Budumuru Department of Oral and Maxillofacial Pathology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia Vishnu Dental College BhimavaramAndhra PradeshIndia Department of Periodontics and Implantology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia Department of Oral Medicine and Radiology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia

Background:Forensic tooth reconstruction is the technique of reconstructing the morphology of a missing tooth from the intra-alveolar morphology of dental sockets from skeletal *** and Objectives:The aim and objective of the study are to compare and investigate whether the anatomy and adaptability of reconstructed teeth simulate with the natural tooth and to investigate whether the dental materials have potential in reconstruction of *** and Methods:An in vitro experimental study was undertaken on a human *** to the Fédération Dentaire Internationale,charting will be done based on the number of teeth *** entire study will be conducted in three phases using dental *** 1 comprised preparation for negative replica,where an impression will be taken,Phase 2 comprised preparation of a positive replica or cast,and Phase 3 comprised tooth reconstruction using the flowable ***:The specimen tooth(which had been taken from its socket)and the newly constructed tooth were compared,and when the length of the newly constructed root was measured using digital vernier calipers,there was a disparity of 0.5-1 *** cone-beam computed tomography radiographs demonstrated the necessary ***:The present study demonstrated that dental information can be obtained even when teeth are absent postmortem by making an attempt to recreate the teeth using dental materials while documenting the intra-alveolar anatomy of the dental root socket.

关键词： Adaptability anatomy reconstruction teeth

New approach for the treatment of vertical root fracture of teeth:A case report and review of literature

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第17期10卷 5816-5824页

作者： Xue Zhong Ping Yan Wei Fan School and Hospital of Stomatology Wuhan UniversityWuhan 430079Hubei ProvinceChina

BACKGROUND Vertical root fracture(VRF)is one of the most common reasons for tooth extraction,although various methods have been applied for saving teeth with *** SUMMARY This case report describes a woman who had a sinus tract on the labial gingiva of the left maxillary central incisor for past two *** probing revealed an 8–10 mm deep,narrow,isolated pocket on the palatal side of the *** and radiographic examination confirmed a longitudinal root fracture.A new approach using a combination of resin and iRoot BP Plus through intentional replantation was used for the treatment of the *** one-year follow-up,the tooth remained asymptomatic with normal periodontal probing depth,and radiographic images showed almost normal bone and periodontal structures around the *** This new approach may be developed as an effective method for saving teeth with VRF.

关键词： Vertical root fracture Intentional replantation iRoot BP Plus Resin teeth Treatment Case report

The Study of the Behaviors of Zinc and Strontium in Caries-Affected teeth by Laser-Induced Breakdown Spectroscopy(LIBS) Technique

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

光谱学与光谱分析 2020年第3期40卷 980-984页

作者： R.Nouir S.Hamzaoui H.Ghalila N.Ja dane Faculty of Sciences of Tunis University of TunisEl ManarTunisTunisia Institute of Medical Technologies of Tunis University of Tunis El ManarTunisTunisia

We report on the application of Laser Induced Breakdown Spectroscopy(LIBS)technique to the study of Ca,P,Zn and Sr evolutions for adult caries-affected teeth using nanosecond laser *** aim of this work is to better understand the behaviors of Zn and Sr as trace-elements in the caries eruption with respect to the behaviors of one of the main compounds of the hydroxyapatite crystal which is the *** study was focused on the investigation of these elements’evolutions from three parts of the enamel surfaces of twenty two adult caries-affected teeth;the healthy part,the dental plaque part and the caries-affected *** decrease rates of Zn,Sr and P was,also,compared to the Ca *** concerned normalized emission line *** every species,normalization was done relatively to the emission line intensities of the healthy *** showed that abundances of these elements decrease similarly from the healthy parts to the affected-caries *** higher decrease rate was noticed for the *** evolutions of Zn and Sr for the three parts of the teeth surfaces cannot inform about the substitution of the calcium by these trace-elements,however the comparison of their decrease rates to the calcium one can be considered as a valuable index of this substitution.

关键词： teeth Caries Trace-elements Substitution LIBS

SEPARATION　CHARACTERISTICS　OF　THE　HYDROCYCLONE　WITH　A　CENTRAL　CONE　AND　ANNULAR　teeth

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1996年第4期6卷 11-15页

作者： Chu, LY Chen, WM Luo, Q NORTHEASTERN UNIV DEPT MINERAL ENGN SHENYANG 110006 PEOPLES R CHINA SICHUAN UNION UNIV DEPT CHEM PROC MACHINERY CHENGDU 610065 PEOPLES R CHINA

ＳＥＰＡＲＡＴＩＯＮＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＴＨＥＨＹＤＲＯＣＹＣＬＯＮＥＷＩＴＨＡＣＥＮＴＲＡＬＣＯＮＥＡＮＤＡＮＮＵＬＡＲＴＥＥＴＨ￥ＣｈｕＬｉａｎｇｙｉｎ；ＣｈｅｎＷｅｎｍｅｉ（Ｄｅｐａｒｔｍｅｎｔｏ... 详细信息

ＳＥＰＡＲＡＴＩＯＮＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＴＨＥＨＹＤＲＯＣＹＣＬＯＮＥＷＩＴＨＡＣＥＮＴＲＡＬＣＯＮＥＡＮＤＡＮＮＵＬＡＲＴＥＥＴＨ￥ＣｈｕＬｉａｎｇｙｉｎ；ＣｈｅｎＷｅｎｍｅｉ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＰｒｏｃｅｓｓｉ...

关键词： ydrocyclone central cone annular teeth separation sharpness classification efficiency separation characteristics

Transplantation of Cryopreserved teeth:A Systematic Review

在线全文

学校读者我要写书评

暂无评论

International Journal of Oral Science 2010年第2期2卷 59-65页

作者： Thanaphum Osathanon Department of Anatomy Faculty of Dentistry Chulalongkorn University

The aim of this article was to examine the research articles regarding biological and mechanical properties of cryopreserved teeth for potential use in tooth transplantation. A systematic review of literatures was performed by Pubmed searching with assigned key words from January 1, 1990 to June 8, 2009. All articles were examined for inclusion criteria. Secondary search was conducted by hand-search through references of included articles from primary search. A total of 24 articles were obtained from both primary and secondary search and used as fundamental articles in this review. Periodontal ligament tissues of cryopreserved teeth were able to maintain their biological properties resulted in a satisfactory healing of periodontium. Dental pulp tissues,however, may be compromised by limitation of permeability of cryopreservative agent into pulp cavity. Therefore, an endodontic treatment of transplanted cryopreserved teeth was recommended. Cryopreserved teeth had comparable mechanical properties to those of normal teeth. Importantly, the success of cryopreserved tooth transplantation treatment in orthodontic patients was reported. The cryopreserved teeth for tooth banking have a potential clinical application for treatment of missing teeth. Case selection, however, is critical for treatment success. More studies and data regarding masticatory function and periodontal healing of transplanted cryopreserved teeth are needed.

关键词： cryopreservation transplantation teeth

Phylogenetic relationships of Cypriniformes and plasticity of pharyngeal teeth in the adaptive radiation of cyprinids

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2019年第4期62卷 553-565页

作者： Wenjing Tao Lei Yang Richard L.Mayden Shunping He Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education) Key Laboratory of Aquatic Science of Chongqing School of Life Sciences Southwest University Florida Museum of Natural History University of Florida Department of Biology Saint Louis University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The Cypriniformes comprise approximately 4,200 species accounting for 25% of the diversity of all freshwater fish, which is widely distributed across the world's continents except Antarctica, South America, and Australia. The highest species diversity is found in Southeastern Asia. Despite its remarkable species diversity and broad-scale geographic patterns of distribution, the evolutionary history of this major freshwater fish group remains largely unresolved. To gain insight of the evolutionary history of Cypriniformes, we present a phylogeny of this group using 1 mitochondrial gene and 15 nuclear genes comprising a total of14,061 bp. Bayesian inference using all gene fragments yielded a well resolved phylogeny, which is mostly consistent with topologies obtained from Maximum Likelihood analyses. Our results further confirmed the monophyly of Cypriniformes and seven constituent subclades including Cyprinidae, Catostomidae, Gyrinocheilidae, Balitoridae, Cobitidae, Nemacheilidae, and Botiidae. Bayesian divergence time analysis indicated that the origin of the Cypriniformes was about 193 Mya during the early Jurassic, coinciding with the onset of the Pangaea breakup. The basal divergence of Cypriniformes is 154 Mya during the late Jurassic. Our findings from molecular divergence and biogeographical analysis indicate the most likely initial geographical range of the ancient Cypriniformes was both East and South Asia(Southeastern area of Mesozoic Laurasia). Moreover, the burst in species diversity in Cyprinidae afforded by the nearly worldwide colonization is possibly in response to the plasticity of pharyngeal dentition. The present study demonstrates that the Cypriniformes was about 193 Mya during the early Jurassic,coinciding with the onset of the Pangaea breakup. The plasticity of pharyngeal dentition of cyprinids might contribute to the burst and radiation of this lineage. The phylogenetic and biogeographic analyses in this study help to improve our understanding

关键词： phylogeny biogeographic analyses Cypriniformes pharyngeal teeth adaptive radiation

Oxygen isotopic variations in modern cetacean teeth and bones： implications for ecological, paleoecological, and paleoclimatic studies

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2016年第1期61卷 92-104页

作者： Burcu Ciner Yang Wang William Parker Department of Earth Ocean and Atmospheric Scienceand National High Magnetic Field LaboratoryFlorida State UniversityTallahasseeFLUSA Department of Geological Engineering Balikesir UniversityBalikesirTurkey department of earth ocean and atmospheric scienceflorida state universityTallahasseeFLUSA

The oxygen isotope ratios （δ18O） preserved in marine sediments have been widely used to reconstruct past ocean temperatures. However, there remain significant uncertainties associated with this method, owing to assumptions about the δ18O of ancient seawater which affects the temperature inferred from sediment δ18O records. In this study, oxygen isotope compositions of phosphate in teeth and bones from five different modem cetacean species, including sperm whale, pygmy sperm whale, short-finned pilot whale, killer whale, and Cuvier＇s beaked whale, and three fossil whales were determined. The data were used to assess whether the oxygen isotope ratios of biogenic phosphate （δ18Op） from cetaceans are a reliable proxy for the oxygen isotopic composition of ocean water （δ18Ow）. The δ18Op values of modem cetaceans range from 15.5 ‰ to 21.3 ‰, averaging （19.6 ‰ ±0.8 ‰）（n = 136）.Using a greatly expanded global cetacean δ18Op dataset, the following regression equation is derived for cetaceans： δ18Ow = 0.95317 （4-0.03293） δ18Op- 17.971 （＋0.605）, r = 0.97253. The new equation, when applied to fossil teeth and bones, yielded reasonable estimates of ancient seawater δ18Ow values. Intra-tooth isotopic variations were observed within individual teeth. Among the selected species, the killer whale （O. orca） has largest intra-tooth δ18Op preference and migratory the lowest δ18Op values and the variation, reflecting its habitat behavior. The results show that oxygen isotope analysis of phosphate in cetacean teeth and dense ear bones provides a useful tool for reconstructing the oxygen isotopic composition of seawater and for examining environmental preferences （including migratory behavior） of both modem and ancient whales.

关键词： Oxygen isotopes Phosphate Cetacean Whales teeth Bones

MORPHOLOGICAL CHANGES IN DEVELOPMENT OF PHARYNGEAL teeth IN MYLOPHARYNGODON PICEUS

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Oceanology and Limnology 1995年第3期13卷 271-277页

作者：乐佩琦 Lake Biwa Museum Project Office Otsu Shiga Prefecture Japan Institute of Hydrobiology Chinese Academy of Sciences Wuhan

Adult pharyngeal teeth in Mylopharyngodon piceus are molariform. Based on SEM observations ofthe developing teeth, this paper describes the morphological diversification of pharyngeal teeth in ***. The larval and juvenile teeth are changed from conical to adult molariform teeth through sevenstages. Comparisons are made between each stage and corresponding types in some species of differentsubfamilies in Cyprinidae. It is considered that the ontogenetic resemblances of the pharyngeal teehbear relationship to the phylogeny of cyprinids.

关键词： Mylopharyngodon piceus pharyngeal teeth morphological diversification

Effect of restoration technique on resistance to fracture of endodontically treated anterior teeth with flared root canals

在线全文

学校读者我要写书评

暂无评论

The Journal of Biomedical Research 2019年第2期33卷 131-138页

作者： Sary S Borzangy Samah M Saker Walid A Al-Zordk Department of Substitutive Dental Sciences College of Dentistry Taibah University Department of Fixed Prosthodontics Faculty of Dentistry Mansoura University

This study was designed to compare the impact of post and core systems on resistance to fracture of endodontically treated anterior teeth with flared root canals and to assess their fracture pattern. Sixty central incisors were cut horizontally 2 mm coronal to the cementoenamel junction(CEJ). After root canal therapy, teeth were assigned into 6 groups(n = 10 each) based on a post system and used as follows: Group C, non-flared root received size #1 glass fiber posts(Control); Group AP, flared root restored with anatomical post; Group RC, flared root restored with size #1 fiber post and cemented with thick layer of resin cement; Group CR, flared root restored with size #1 and reinforced with composite resin; Group CM, cast post-core; Group CP, CAD/CAM polymer-infiltrated ceramic post and *** post cementation, core build-up and crown insertion, the specimens were thermo-cycled up to 10,000 cycles(5 C/55 C; 30 seconds dwell time, 6 seconds transition time) and then statically loaded at 1 mm/minute crosshead speed using a universal testing machine. One-way ANOVA and Tukey HSD post hoc test(α= 0.05) were used for data analysis. Group C recorded significantly higher resistance to fracture values [(826.9±39.1) N] followed by group CP [(793.8±55.6) N] while group RC yielded the lowest fracture resistance values [(586.7±51.4) N]. The resistance to fracture of wide root canals can be enhanced by using one-piece CAM/CAM post and core as an alternative to the use of either glass fiber post, relined with composite resin increasing the thickness of luting cement or the use of cast post and core system. However, this was an in vitro investigation and further in vivo studies are necessary.

关键词： anatomical post customized post endodontically treated teeth flared root canal