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1.
Biomed Res Int ; 2015: 187173, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26413507

RESUMO

An important preprocess in computer-aided orthodontics is to segment teeth from the dental models accurately, which should involve manual interactions as few as possible. But fully automatic partition of all teeth is not a trivial task, since teeth occur in different shapes and their arrangements vary substantially from one individual to another. The difficulty is exacerbated when severe teeth malocclusion and crowding problems occur, which is a common occurrence in clinical cases. Most published methods in this area either are inaccurate or require lots of manual interactions. Motivated by the state-of-the-art general mesh segmentation methods that adopted the theory of harmonic field to detect partition boundaries, this paper proposes a novel, dental-targeted segmentation framework for dental meshes. With a specially designed weighting scheme and a strategy of a priori knowledge to guide the assignment of harmonic constraints, this method can identify teeth partition boundaries effectively. Extensive experiments and quantitative analysis demonstrate that the proposed method is able to partition high-quality teeth automatically with robustness and efficiency.


Assuntos
Modelos Dentários , Processamento de Imagem Assistida por Computador/métodos , Dente/anatomia & histologia , Gráficos por Computador , Humanos
2.
Dongwuxue Yanjiu ; 31(3): 310-8, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20672421

RESUMO

Understory birds in monsoon evergreen broadleaved forest of Mengyang, Xishuangbanna, Yunnan were sampled using mist nets from October 2008 to March 2009. A total of 1423 individuals of 90 species belonging to 28 families and 7 orders were captured, among which there are 8 dominant bird species, i.e., Sliver-breasted Broadbill (Serilophus lunatus), Brown-cheeked Fulvatta (Alcippe poioicephala), White-throated Bulbul (Alophoixus pallidus), Golden-spectacled Warbler (Seicercus burkii), White-tailed Robin (Cinclidium leucurum), Black-breasted Thrush (Turdus dissimilis), Streak-Breasted Jungle Babbler (Pellorneum ruficeps), and Buff-breasted Jungle Babbler (Trichastoma tickelli). Resident birds, the major composition of the understory birds, accounted for 89.3 percent of total captures. The mean capture rate was 9.0+-3.7 individuals/(100 net-hours) and it differed significantly between months, highest in December 2008 (12.5+-1.3)individuals/(100 net-hours), lowest in February 2009 (5.2+-0.6) individuals/(100 net-hours). The most significant characteristic of understory birds in Xishuangbanna is more species abundance and lower species density compared to understory bird composition of South China. Another characteristic is that no obvious dominance pattern was observed in Babbler species. We also noticed that silver-breasted Broadbill, National Key Protection Bird, is the most abundance species in our captures, thus their habitat require further protection.


Assuntos
Ecossistema , Árvores , Animais , Aves , China , Conservação dos Recursos Naturais , Estações do Ano
3.
Comp Biochem Physiol B Biochem Mol Biol ; 151(2): 183-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18639644

RESUMO

Delta(6)-Desaturase (linoleoyl-CoA desaturase, EC 1.14.19.3) is the rate-limiting enzyme in the biosynthetic pathway of highly unsaturated fatty acid (HUFA). In this report, a Delta6 desaturase-like cDNA was cloned, and the relation of HUFA biosynthetic activity in liver with ambient salinity as well as dietary fatty acids was investigated in the euryhaline teleost Siganus canaliculatus. After the juveniles were fed four formulated diets (D1-D4) with different essential fatty acid composition (D1 with 23.49% HUFA, D2-D4 were HUFA-free, linoleic and alpha-linolenic acids account for 21.1% and 0.38%, 13.99% and 11.64%, 18.31% and 5.82% of the total fatty acids, respectively) for nine weeks, the growth performance showed no difference among groups in brackish water (10 ppt) or seawater (32 ppt) (P>0.05). Comparing liver fatty acids with fish fed D1, the content of arachidonic acid in fish fed D2 or D4 was significantly higher in 10 ppt (P<0.05), but showed no difference in 32 ppt; the contents of eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acids in 10 ppt, as well as EPA in 32 ppt in fish fed D3 showed no difference, whereas those of DPA and DHA were significantly lower in 32 ppt (P<0.05). These data suggest that S. canaliculatus may convert linoleic and alpha-linolenic acids into HUFA and such a capacity was stronger in low salinity than that in high salinity. Consistent with this, the liver levels of Delta6 desaturase mRNA in fish fed D2-D4 were generally higher than in fish fed D1 in both salinities, and the total expression level in 10 ppt was about 1.56 times of that in 32 ppt, suggesting that transcriptional control of Delta6 desaturase is involved in such a HUFA biosynthesis. To our knowledge, this is the first report showing the relation of HUFA biosynthetic activity with ambient salinity in a euryhaline fish.


Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Essenciais/administração & dosagem , Linoleoil-CoA Desaturase/genética , Fígado/metabolismo , Perciformes/genética , Perciformes/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA/genética , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/biossíntese , Expressão Gênica , Linoleoil-CoA Desaturase/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Salinidade , Água do Mar , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(1): 36-9, 51, 2006 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-16562672

RESUMO

OBJECTIVE: To investigate the lymphangiogenesis and location of tumor lymphatic vessels induced by vascular endothelial growth factor C (VEGF-C) in primary breast cancer. METHODS: The expression of VEGF-C mRNA in 89 cases of primary breast cancer was detected by in situ hybridization, and lymphatic vessels with vascular endothelial growth factor receptor-3 (VEGFR-3) were labeled by immunohistochemistry SP method. RESULTS: VEGF-C mRNA expressed in 49 of all 89 cases of primary breast cancer, and the expression rate was 55.06%. The expression of VEGF-C mRNA was positively correlated with lymphatic vessel density (LVD) and axillary lymph node metastasis, LVD and the rate of axillary lymph node metastasis were significantly higher in VEGF-C mRNA positive group than those in the negative group (both P < 0.05). Different levels of lymphangiogenesis took place in all cases of breast cancer, but it was mainly located in tumor stroma, and apparently mature lymphatic vessels were not found in cancer nests. LVD was positive related with the clinical stage and axillary lymph node metastasis in breast cancer; the clinical stage, the LVD, the axillary lymph node metastasis in positive group were higher than those in the negative group (P < 0.05). CONCLUSION: The expression of VEGF-C mRNA is positively correlated with lymphangiogenesis and axillary lymph node metastasis in primary breast cancer. Lymphangiogenesis induced by VEGF-C predominantly takes place in the tumor stroma tissue, and mature lymphatic vessels are not found in cancer nests.


Assuntos
Neoplasias da Mama/patologia , Linfangiogênese , Fator C de Crescimento do Endotélio Vascular/biossíntese , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fator C de Crescimento do Endotélio Vascular/genética
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