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71.
中草药白花蛇舌草等对实验性大肠癌作用机制的研究   总被引:2,自引:0,他引:2  
目的探讨白花蛇舌草等中药在体内对大肠癌的抑制作用和抑瘤机制。方法以大肠癌裸鼠移植瘤为动物模型,观察肿瘤的生长速度,免疫组化法及肠道菌群培养技术观察大肠癌裸鼠移植瘤PCNA表达及阳性细胞密度、肿瘤坏死因子和白介素6的表达以及肠道菌群的培养。结果白花蛇舌草和仙鹤草用药组肿瘤生长率小于对照组,达50.86%,微生态调节剂组低于用药组;在肠道菌群及免疫调节能力上用药组优于对照组,微生态调节剂组优于用药组。结论白花蛇舌草和仙鹤草在体内能显著抑制大肠癌的生长。  相似文献   
72.
动物舌温与血液灌注率的关系特性研究   总被引:3,自引:0,他引:3  
结合中医舌诊机理而进行的生物传热研究具有重要的意义。采用多种先进仪器和手段,在大量动物实验的基础上,通过对动物造模改变猪舌的血液灌注率,测试相应条件下的舌面温度,得到舌表面不同位置处的温度与血液灌注率之间的关系。结果表明,舌表面温度随血液灌注率的增加而升高,但血液灌注率增大到一定值后,舌面温度将维持不变,血液灌注率值也不再增长。通过实验得到的温度与血液灌注率间的变化规律,将为建立适合于舌体传热特性的生物传热模型提供客观依据。  相似文献   
73.
This paper presents a novel inverse estimation approach for the active contraction stresses of tongue muscles during speech. The proposed method is based on variational data assimilation using a mechanical tongue model and 3D tongue surface shapes for speech production. The mechanical tongue model considers nonlinear hyperelasticity, finite deformation, actual geometry from computed tomography (CT) images, and anisotropic active contraction by muscle fibers, the orientations of which are ideally determined using anatomical drawings. The tongue deformation is obtained by solving a stationary force-equilibrium equation using a finite element method. An inverse problem is established to find the combination of muscle contraction stresses that minimizes the Euclidean distance of the tongue surfaces between the mechanical analysis and CT results of speech production, where a signed-distance function represents the tongue surface. Our approach is validated through an ideal numerical example and extended to the real-world case of two Japanese vowels, /ʉ/ and /ɯ/. The results capture the target shape completely and provide an excellent estimation of the active contraction stresses in the ideal case, and exhibit similar tendencies as in previous observations and simulations for the actual vowel cases. The present approach can reveal the relative relationship among the muscle contraction stresses in similar utterances with different tongue shapes, and enables the investigation of the coordination of tongue muscles during speech using only the deformed tongue shape obtained from medical images. This will enhance our understanding of speech motor control.  相似文献   
74.
This review summarizes findings concerning the unique developmental characteristics of mouse head muscles (mainly the masticatory and tongue muscles) and compares their characteristics with those of other muscles. The developmental origin of the masticatory muscles is the somitomeres, whereas the tongue and other muscles, such as the trunk (deep muscles of the back, body wall muscles) and limb muscles, originate from the somites. The program controlling the early stages of masticatory myogenesis, such as the specification and migration of muscle progenitor cells, is distinctly different from those in trunk and limb myogenesis. Tongue myogenesis follows a similar regulatory program to that for limb myogenesis. Myogenesis and synaptogenesis in the masticatory muscles are delayed in comparison with other muscles and are not complete even at birth, whereas the development of tongue muscles proceeds faster than those of other muscles and ends at around birth. The regulatory programs for masticatory and tongue myogenesis seem to depend on the developmental origins of the muscles, i.e., the origin being either a somite or somitomere, whereas myogenesis and synaptogenesis seem to progress to serve the functional requirements of the masticatory and tongue muscles. This study was supported by grants-in-aid for funding scientific research (nos. 13671955 and 16591871), the Bio-ventures and High-Technology Research Center of the Ministry of Education, Culture, Sports, Science, and Technology of Japan, and the Science Research Promotion Fund from the Promotion and Mutual Aid Corporation for Private Schools of Japan.  相似文献   
75.
To investigate the role of bone morphogenetic proteins (BMPs) in the differentiation process of skeletal muscle, we analyzed the in vivo expression of BMP2 and BMP4, of BMP receptors (BMPR) IA, IB, and II, and of activin receptors (ActR) IA, II, and IIB in mouse tongue muscle between embryonic day 11 (E11) and E17. The mRNA expression levels for BMP2 were 5-fold to 11-fold greater than those for BMP4 between E13 and E17 (P < 0.05-0.01). Expression of the BMP2, BMPRIB, ActRIA, ActRII, and ActRIIB proteins was first observed at E13. Expression of BMP2 and BMPRIB was detected in the whole area of the differentiating muscle tissues identified by immunostaining for fast myosin heavy chain (fMHC), but that of ActRIA, ActRII, and ActRIIB was detected only in the peripheral area of the differentiating muscle tissues. In the E15 tongue, all of the BMPs, BMPRs, and ActRs studied herein were expressed in the whole area of the differentiating muscle tissues identified by immunostaining for fMHC. These results suggest that BMPs play a role in the differentiation of tongue muscle tissues at E15 but have little or no effect at E13. This study was supported in part by grants-in-aid for funding scientific research (no. 16591871 to A.Y.) from the Bio-ventures and High-Technology Research Center of the Ministry of Education, Culture, Sports, Science, and Technology of Japan and by the Science Research Promotion Fund from the Promotion and Mutual Aid Corporation for Private Schools of Japan.  相似文献   
76.
BackgroundThe aim of this study was to investigate the relationship between high-risk genotypes of Human Papilloma Virus (HPV) and cancer of different subsites of the oral cavity.Material and methodsA pooled analysis of five studies included on the International Head and Neck Cancer Epidemiology (INHANCE) Consortium was conducted. HPV 16 and HPV 18 were considered. Adjusted odds ratios (ORs) and corresponding 95 % confidence intervals (CIs) for HPV and each oral cavity subsites were simultaneously estimated using multinomial logistic regression models.ResultsThe analysis included 1157 cases and 3272 controls. This study showed a slightly higher prevalence of HPV infection among oral cancer cases than controls. In particular, an increased risk of other and not otherwise specified (NOS) sites within the oral cavity, oral tongue, palate and floor of mouth cancer was observed for overall HPV16 positivity (OR = 1.66, 95 % CI: 1.01−2.72; OR = 1.97, 95 % CI: 1.36−2.85; OR = 2.48, 95 % CI: 1.50−4.11; OR = 2.71, 95 % CI: 1.06−6.95, respectively). In particular, HPV16E7 was related to cancer of floor of mouth, oral cavity NOS and palate (OR = 2.71, 95 % CI: 1.06−6.95; OR = 3.32, 95 % CI:1.53−7.19; OR = 3.34, 95 % CI:1.38−8.06). Results were inconsistent for HPV18 due to low prevalence of infection.ConclusionOur study suggests that HPV16 infection may increase the risk of developing floor of mouth, gum, tongue, and palate cancers.Clinical relevanceSubjects with HPV infection have a higher risk of cancer from all sites of the oral cavity.  相似文献   
77.
Deregulations of microRNA have been frequently observed in tongue squamous cell carcinoma (TSCC), but their roles in tumorigenesis are not entirely clear. Here, we reported the up-regulation of miR-24 in TSCC. MiR-24 up-regulation reduced the expression of RNA-binding protein dead end 1 (DND1). Knockdown of miR-24 led to enhanced expression of DND1. The direct targeting of miR-24 to the DND1 mRNA was predicted bioinformatically and confirmed by luciferase reporter gene assays. Furthermore, the miR-24-mediated change in DND1 expression suppressed the expression of cyclin-dependent kinase inhibitor 1B (CDKN1B), and also led to enhanced proliferation and reduced apoptosis in TSCC cells.  相似文献   
78.
目的

探讨慢性萎缩性胃炎患者和慢性浅表性胃炎患者胃内幽门螺杆菌(Helicobacter pylori, H.pylori)感染与舌苔菌群的关系。

方法

根据61名患者内镜、病理和H.pylori检测结果, 将其分成慢性萎缩性胃炎H.pylori阳性组(12名)、慢性萎缩性胃炎H.pylori阴性组(16名)、慢性浅表性胃炎H.pylori阳性组(8名)和慢性浅表性胃炎H.pylori阴性组(25名)。采集舌苔样本进行16S rRNA基因测序, 分析各组患者舌苔菌群结构。

结果

16S rRNA基因测序结果显示, 此次测序样本数据量足够, 样本所含物种的丰富程度和均匀程度合理。4组舌苔菌群样本中Observed species指数差异有统计学意义(H=10.023 3, P < 0.05)。门水平上, 舌苔菌群由拟杆菌门、厚壁菌门、变形菌门3大优势菌门组成。属水平上, 4组间共有11种菌属的丰度差异有统计学意义(均P < 0.05)。在慢性萎缩性胃炎患者中, H.pylori阳性的患者拟普雷沃菌属相对丰度显著低于H.pylori阴性患者, 而罗氏菌属的相对丰度则显著升高。此外, 61例舌苔菌群样本中, 仅1例检测到H.pylori

结论

H.pylori感染与舌苔菌群结构存在相关性, 然而胃内与口腔中H.pylori的具体关联还需要进一步研究。

  相似文献   
79.
80.
The cell-of-origin has a great impact on the types of tumors that develop and the stem/progenitor cells have long been considered main targets of malignant transformation. The SV40 (SV40—Simian Virus 40) large T and small t antigens (T/t), have been targeted to multiple-differentiated cellular compartments in transgenic mice. In most of these studies, transgenic animals develop tumors without apparent defects in animal development. In this study, we used the bovine keratin 5 (BK5) promoter to target the T/t antigens to stem/progenitor cell-containing cytokeratin 5 (CK5) cellular compartment. A transgene construct, BK5-T/t, was made and microinjected into the male pronucleus of FVB/N mouse oocytes. After implanting ∼1700 embryos, only 7 transgenics were obtained, including 4 embryos (E9.5, E13, E15, and E20) and 3 postnatal animals, which died at P1, P2, and P18, respectively. Immunohistological analysis revealed aberrant differentiation and prominent hyperplasia in several transgenic CK5 tissues, especially the upper digestive organs (tongue, oral mucosa, esophagus, and forestomach) and epidermis, the latter of which also showed focal dysplasia. Altogether, these results indicate that constitutive expression of the T/t antigens in CK5 cellular compartment results in abnormal epithelial differentiation and leads to embryonic/perinatal animal lethality.  相似文献   
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