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111.
112.
人体微生物组是指人体体表及内部的微生物的遗传信息总和,与人类健康与疾病状态存在密切关系。口腔和肠道微生物是最具多样化的微生物群落,两者可以交互影响,在疾病发生发展过程中共同发挥作用,并可以实时反映机体的健康与疾病状态。2型糖尿病是由遗传和环境因素引起的代谢紊乱,最近的研究指出微生物与糖尿病存在关联。本文结合近期的研究进展,就2型糖尿病患者口腔微生物和肠道微生物的特征进行综述,有望为探索基于微生物组特征的2型糖尿病风险预测、诊断和预后预测的疾病模型的建立提供参考依据。 相似文献
113.
不同代数人牙周膜细胞成骨特征稳定性的实验研究 总被引:4,自引:2,他引:4
目的:观察培养代数牙周膜细胞的成骨细胞表型特征的影响。方法:利用4、6、8、10代细胞进行以形态学、细胞生长曲线、碱性磷酸酶(ALP)活性测定以及矿化能力和面积的观察。结果:在细胞形态和超微结构、细胞生长曲线、碱性磷酸酶活性和矿化能力方面,第4、6、8、10代无明显差别;10代以后的细胞各方面指标减弱,提示细胞进入衰老期。结论:利用10代以内牙周膜细胞进行实验或移植其结果可靠。 相似文献
114.
A custom mandibular distraction device for the rat 总被引:1,自引:0,他引:1
Connolly JP Liu ZJ Wang L Whelan MF Huang GJ Williams JK King GJ 《The Journal of craniofacial surgery》2002,13(3):445-50; discussion 450-2
In the last several years, the rat model has been used as a reliable means of studying distraction osteogenesis (DO). This model has several benefits, including lower cost, the availability of molecular reagents for the rat, and the ability to perform a large number of operations in a short time. We have recently developed an external device that is custom-made for the rat mandible and secured at the mandibular ramus. The device consists of a Leone (Florence, Italy) jackscrew distraction assembly (0.2 mm per one-quarter turn), 2 Luhr L-shaped 0.8-mm five-hole microplates, and four 0.8-mm x 3-mm microscrews (Stryker-Leibinger Corp., Kalamazoo, MI) for fixation. Additionally, there is a methylmethacrylate block that is placed on the lingual surface of the angle of the mandible to support the posterior screws. Sterile surgical technique was used, and the same two surgeons performed all operations. To date, we have operated on 153 Sprague-Dawley rats. The procedure has been well tolerated by the animals. We had 17 postoperative deaths (11% mortality), largely as a result of anesthetic complications. There were no wound infections or dehiscence. A mandible fracture was noted in 6 rats (4%), which occurred at the time of device placement. There were no device dislodgments. Postmortem examination showed the device to be well positioned in all rats, with good callous formation at the distraction site. The rats surpassed their preoperative weight after an average of 9.2 days. These results compare favorably with those of other models currently in use. We have developed a device that is currently being used in the study of DO in the rat mandible. Our device is small in size, does not require wide undermining for its placement, and has had a low incidence of device dislodgment or infection. This model has shown great reproducibility and thus should be effective in its application for the histologic and biochemical investigation of DO in the rat. 相似文献
115.
目的 :研究In Ceram氧化铝基底在玻璃料渗透前及反复多次玻璃料渗透后样本的微观结构 ,探讨渗透次数对微观结构的影响。方法 :分别观察玻璃料渗透前、玻璃料渗透 1~ 5次的样本的SEM断面。结果 :In Ceram氧化铝烧结后 ,形成了连续开放的多孔网状结构。玻璃料渗透后 ,氧化铝颗粒之间的孔隙被渗透玻璃充盈、占据 ,二相互相锁结。结论 :In Ceram氧化铝基底在渗透前后 ,微观形貌发生明显改变 ;随着渗透次数的增加 ,渗透深度逐渐加深 ,微观结构也更为致密 相似文献
116.
117.
The human oral cavity contains a complex microbial community that, until recently, has not been well characterized. Studies using molecular tools have begun to enumerate and quantify the species residing in various niches of the oral cavity; yet, virtually every study has revealed additional new species, and little is known about the structural dynamics of the oral microbial community or how it changes with disease. Current estimates of bacterial diversity in the oral cavity range up to 700 species, although in any single individual this number is much lower. Oral microbes are responsible for common chronic diseases and are suggested to be sentinels of systemic human diseases. Microarrays are now being used to study oral microbiota in a systematic and robust manner. Although this technology is still relatively young, improvements have been made in all aspects of the technology, including advances that provide better discrimination between perfect-match hybridizations from non-specific (and closely-related) hybridizations. This review addresses a core technology using gel-based microarrays and the initial integration of this technology into a single device needed for system-wide studies of complex microbial community structure and for the development of oral diagnostic devices. 相似文献
118.
目的评价Raypex5根尖定位仪测量根管工作长度与X线法的符合性。方法用Raypex5根尖定位仪对205颗患牙共403个根管进行根管工作长度测量,以此长度进行根管预备充填后拍摄X线片观察根管充填的质量。结果Raypex5根尖定位仪测量根管工作长度后根管适充率为96.28%。结论Raypex5根尖定位仪是一种准确可靠安全有效根管工作长度测量仪器。 相似文献
119.
120.
Cephalometric analysis of maxillofacial morphology in unoperated cleft palate patients. 总被引:6,自引:0,他引:6
H Yoshida A Nakamura K Michi G M Wang K Liu W L Qiu 《The Cleft palate-craniofacial journal》1992,29(5):419-424
This study was designed to investigate maxillofacial morphology in adolescents and adults with unrepaired cleft palate, with or without cleft lip. Twenty-two Chinese patients with unilateral cleft lip and palate (the UCLP group), and 21 Chinese with cleft palate (the CP group) were cephalometrically evaluated and classified into the five ranges established from the means and standard deviations for matched normal Chinese populations. Many subjects in both UCLP and CP groups showed an intrinsic maxillary retrusion and a steeper mandible. The others had nearly normal maxillofacial morphology. The tendency for maxillary retrusion and a steeper mandible became increasingly remarkable with age. In the long axis of upper incisors in subjects with permanent dentition, there were no UCLP subjects with labial inclination, whereas three CP subjects exhibited labial inclination. 相似文献