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91.
Marginal Bone Preservation in Single‐Tooth Replacement: A 5‐Year Prospective Clinical Multicenter Study 下载免费PDF全文
92.
目的:观察下颌骨功能性偏斜对发育期大鼠髁突软骨内I型、II型以及III型胶原纤维分布及表达的影响。方法:取4周龄雄性SD大鼠40只,随机分为实验组(20只)和正常对照组(20只)。实验组佩戴自制的上切牙金属牙套引导下颌骨功能性右偏,对照组不佩戴任何装置,分别于实验1周、4周取得标本。HE染色及番红-O染色观察髁突软骨组织形态,苦味酸-天狼猩红偏振光染色以及免疫组化染色分别观察髁突软骨内I型、II型、III型胶原纤维含量以及分布表达情况,并进行相关半定量图像分析。结果:HE以及番红-O染色显示,实验1周后实验组牵张侧较正常组髁突软骨厚度显著增加,到4周后两组差异不显著;而实验组受压侧髁突软骨厚度4周后显著下降。天狼猩红染色及免疫组化染色结果显示,I型胶原主要表达在增殖层至成骨细胞层,II型胶原主要表达在软骨细胞层和肥大层。与正常组相比,1周及4周时实验组牵张侧软骨中区I型及II型胶原表达增强;受压侧软骨后区I型及II型胶原表达均显著减少。III型胶原主要表达在软骨纤维层至软骨细胞层,两组间无显著表达差异。结论:下颌骨功能性偏斜导致两侧髁突软骨发生了差异性生长改建,I型及II型胶原参与了改建中软骨内骨化过程。 相似文献
93.
目的采用pH梯度法制备重酒石酸长春瑞滨长循环脂质体并进行表征。方法以粒径为指标,考察水化温度和挤出次数对空白脂质体粒径的影响;以粒径及包封率为指标,考察孵化温度和孵化时间对载药脂质体粒径和包封率的影响。并采用Malvern粒度仪测定脂质体的粒径分布、多分散系数及Zeta电位,透射电镜考察其形态,并考察脂质体稳定性。结果重酒石酸长春瑞滨长循环脂质体粒径(96.4±27.2) nm,多分散系数(0.162±0.042),Zeta电位(-26.7±3.5) mV;透射电镜显示脂质体粒径均一,成单层膜球状分布;长期稳定性研究显示,脂质体在5 ℃条件下放置3个月稳定。结论pH梯度法可以用于重酒石酸长春瑞滨长循环脂质体的制备。 相似文献
94.
Background:
Superior semicircular canal dehiscence (SSCD) is gradually recognized by otologists in recent years. The patients with SSCD have a syndrome comprising a series of vestibular symptoms and hearing function disorders which can be cured by the operation. In this study, we evaluated the characteristics of patients with SSCD and determined the effectiveness of treating this syndrome by resurfacing the canal via the transmastoid approach using a dumpling structure.Methods:
Patients with SSCD, confirmed by high-resolution computed tomography and hospitalized at Beijing Tongren Hospital between November 2009 and October 2012, were included in the study. All of the patients underwent the unilateral transmastoid approach for resurfacing the canal, and received regular follow-up after surgery. Data from preoperative medical records and postoperative follow-up were comparatively analyzed to evaluate the effect of surgery.Results:
In total, 10 patients and 13 ears (three left ears, four right ears, three bilateral ears) were evaluated in the study, which included 7 men and 3 women. Different symptoms and distinctive manifestations of vestibular evoked myogenic potential were found in these patients. After surgery, 4 patients had complete resolution, 5 had partial resolution, and 1 patient, with bilateral SSCD, had aggravation. None of the patients suffered from serious complications such as sensorineural hearing loss, facial paralysis, cerebrospinal fluid leakage, or intracranial hypertension.Conclusions:
In patients with unilateral SSCD, resurfacing the canal via the transmastoid approach using a dumpling structure is an effective and safe technique. However, more consideration is needed for patients with bilateral SSCD. 相似文献95.
96.
Danilo Alessio Di Stefano Paolo Arosio Adriano Piattelli Vittoria Perrotti Giovanna Iezzi 《The journal of advanced prosthodontics》2015,7(1):51-55
PURPOSE
Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them.MATERIALS AND METHODS
A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data.RESULTS
The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement.CONCLUSION
The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it. 相似文献97.
抗菌肽广泛存在于多种生物体内,是生物体非特异性免疫功能的重要组成部分。其可以保护机体免受细菌、真菌、寄生虫和病毒等病原体的侵袭,还具有介导催化、凋亡、免疫调节活性、促进伤口愈合和促成骨等作用,是钛金属内植物表面抗菌涂层研究的热点,具有良好的应用前景。本文就应用于钛金属内植物表面的抗菌肽的抗菌机制、加载方式和应用现状等进行综述。 相似文献
98.
An experimental case study was carried out to investigate the shear performance of reinforced concrete beams with small circular openings under a cyclic anti-symmetric bending moment. The openings were strengthened by using a newly developed reinforcement continuously bent into rectangular and octagonal shapes, which was convenient for installation and effective for crack control. The presence of web opening reinforcement, the reinforcing method, and the web opening spacing were employed as main variables in the design of five specimens. The cyclic performance of all specimens was evaluated in terms of failure mode, crack pattern, strength and stiffness degradation, and strain distribution. Experimental results were discussed to assess the suitability of the proposed web opening reinforcement in RC web opening beams. It was confirmed that the proposed web opening reinforcement exhibited outstanding crack control and served as a shear resistance component in place of the concrete cross-section lost due to web openings. Finally, the shear strength of all specimens, obtained from the cyclic loading tests, were compared with those obtained from the equation proposed by Mansur (1998) and the Architectural Institute of Japan standard 2010. 相似文献
99.
Min Jin Lhee Youn Jin Cha Jong Man Bae Young Tae Kim Nam Hoon Cho 《Yonsei medical journal》2014,55(2):331-338
Purpose
Landmark indicators have not yet to be developed to detect the regression of cervical intraepithelial neoplasia (CIN). We propose that quantitative viral load and indicative histological criteria can be used to differentiate between atypical squamous cells of undetermined significance (ASCUS) and a CIN of grade 1.Materials and Methods
We collected 115 tissue biopsies from women who tested positive for the human papilloma virus (HPV). Nine morphological parameters including nuclear size, perinuclear halo, hyperchromasia, typical koilocyte (TK), abortive koilocyte (AK), bi-/multi-nucleation, keratohyaline granules, inflammation, and dyskeratosis were examined for each case. Correlation analyses, cumulative logistic regression, and binary logistic regression were used to determine optimal cut-off values of HPV copy numbers. The parameters TK, perinuclear halo, multi-nucleation, and nuclear size were significantly correlated quantitatively to HPV copy number.Results
An HPV loading number of 58.9 and AK number of 20 were optimal to discriminate between negative and subtle findings in biopsies. An HPV loading number of 271.49 and AK of 20 were optimal for discriminating between equivocal changes and obvious koilocytosis.Conclusion
We propose that a squamous epithelial lesion with AK of >20 and quantitative HPV copy number between 58.9-271.49 represents a new spectrum of subtle pathological findings, characterized by AK in ASCUS. This can be described as a distinct entity and called "regressing koilocytosis". 相似文献100.
This study aimed to prepare titania (TiO2) nanotube (TNT) arrays grown on un-activated carbon fibers (UCFs), with the application of different TiO2 loadings based on the coating-hydrothermal process, and to evaluate their photocatalytic activity for the degradation of sub-ppm levels of aromatic pollutants (benzene, toluene, ethyl benzene, and o-xylene (BTEX)) using a plug-flow photocatalytic reactor. The characteristics of the prepared photocatalysts were determined by scanning electron microscopy (SEM),energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), UV-visible absorption spectroscopy (UV-Vis) and X-ray diffraction (XRD) analyses. Spectral analysis showed that the prepared photocatalysts were closely associated with the characteristics of one-dimensional nanostructured TiO2 nanotubes for TNTUCFs and spherical shapes for TiO2-coated UCF (TUCF). The photocatalytic activities of BTEX obtained from TNTUCFs were higher than those obtained from a reference photocatalyst, TUCF). Specifically, the average degradation efficiencies of BTEX observed for TNTUCF-10 were 81%, 97%, 99%, and 99%, respectively, while those observed for TUCF were 14%, 42%, 52%, and 79%, respectively. Moreover, the photocatalytic activities obtained for TNTUCFs suggested that the degradation efficiencies of BTEX varied with changes in TiO2 loadings, allowing for the optimization of TiO2 loading. Another important finding was that input concentrations and air flow rates could be important parameters for the treatment of BTEX, which should be considered for the optimization of TNTUCFs application. Taken together, TNTUCFs can be applied to effectively degrade sub-ppm levels of gas-phase aromatic pollutants through the optimization of operational conditions. 相似文献