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51.
目的评估异种脱细胞真皮基质植入上前牙种植区唇侧软组织的临床美学效果。方法对30例单个上前牙缺失患者行美学区单颗种植义齿修复的患者进行回顾性研究。随机分为实验组和对照组,实验组行种植术伴种植区唇侧异种脱细胞真皮基质骨膜下植入术,对照组行单纯种植术。种植义齿负载半年后按一定标准拍摄口内照片,两位观察者用红色美学指数评估口内照片中种植体周软组织各项得分。分组进行统计学分析,分析不同软组织处理与红色美学指数值之间的关系。结果种植义齿负载半年后两组种植体留存率均为100%;实验组红色美学指数平均为10.77±2.56分,对照组的红色美学指数平均9.57±2.10分,两组比较,实验组患者红色美学指数较高(P<0.05)。结论在上颌前牙美学区进行单牙种植修复时,采取异种脱细胞真皮基质骨膜下植入,可以改善种植区唇侧的美学效果。 相似文献
52.
Sung-Ho Huh Katja N?rhi P?ivi H. Lindfors Otso H??r? Lu Yang David M. Ornitz Marja L. Mikkola 《Genes & development》2013,27(4):450-458
In hair follicle development, a placode-derived signal is believed to induce formation of the dermal condensation, an essential component of ectodermal organs. However, the identity of this signal is unknown. Furthermore, although induction and patterning of hair follicles are intimately linked, it is not known whether the mesenchymal condensation is necessary for inducing the initial epithelial pattern. Here, we show that fibroblast growth factor 20 (Fgf20) is expressed in hair placodes and is induced by and functions downstream from epithelial ectodysplasin (Eda)/Edar and Wnt/β-Catenin signaling to initiate formation of the underlying dermal condensation. Fgf20 governs formation of primary and secondary dermal condensations in developing hair follicles and subsequent formation of guard, awl, and auchene hairs. Although primary dermal condensations are absent in Fgf20 mutant mice, a regular array of hair placodes is formed, demonstrating that the epithelial patterning process is independent of known histological and molecular markers of underlying mesenchymal patterns during the initial stages of hair follicle development. 相似文献
53.
Spinal dysraphic lesions due to focal nondisjunction in primary neurulation are commonly encountered in paediatric neurosurgery, but the “fog-of-war” on these conditions was only gradually dispersed in the past 10 years by the works of the groups led by the senior author and Prof. Kyu-Chang Wang. It is now clear that limited dorsal myeloschisis and congenital spinal dermal sinus tract are conditions at the two ends of a spectrum; and mixed lesions of them with various configurations exist. This review article summarizes the current understanding of these conditions’ embryogenetic mechanisms, pathological anatomy and clinical manifestations, and their management strategy and surgical techniques. 相似文献
54.
《International journal of oral and maxillofacial surgery》2020,49(6):726-733
Patient dissatisfaction with labial appearance in the adult cleft lip is frequently linked to poor upper lip projection. Other areas of concern include asymmetry and impaired upper lip height. Different surgical techniques are available to address volumetric deficiencies, according to extent and localization. However, data comparing outcomes in these different areas are limited. The main aim of this study was to assess the relative gains in upper lip projection. An evaluation of upper vermilion height and symmetry was also performed. Thirty-seven consecutive patients treated by a single surgeon had their pre- and postoperative results measured using standardized photographs; these were analysed using subjective and objective outcome measures. Seven examiners evaluated anonymized pre- and postoperative side and front views for subjective evaluation. The objective analysis was performed using Adobe Photoshop. Fifteen lip revisions, four Abbe flaps, 12 dermal grafts, and six PermaLip implants were performed. In bilateral cleft lip and palate patients, Abbe flaps showed the most significant improvement in labial projection, followed by PermaLip implants and dermal grafts. In unilateral cleft lip and palate patients, PermaLip implants best addressed impaired lip projection, followed by dermal grafts. Overall, functional lip revisions showed excellent outcomes for upper lip symmetry; however, only minor changes in labial projection were found. 相似文献
55.
Targeted delivery of adipose‐derived stem cells via acellular dermal matrix enhances wound repair in diabetic rats 下载免费PDF全文
Daping Yang Tong Liu Dan Liu Jin Xu Jiewu Zhang 《Journal of tissue engineering and regenerative medicine》2015,9(3):224-235
Cell‐based therapeutic intervention has emerged as a new approach to accelerate wound closure. Adipose‐derived stem cells (ASCs), as a fascinating cell source, have received much attention in tissue repair and regeneration. In this study we evaluated the potential of acellular dermal matrix (ADM) scaffold serving as a carrier for the delivery of ASCs and investigated its therapeutic effects on wound healing. First, ASCs were isolated and characterized for multidifferentiation potential. ASCs–ADM grafts were then prepared, and ADM scaffold was shown to support the in vitro growth and proliferation of ASCs. Next, we analysed paracrine factors in conditioned medium and found that ASCs–ADM grafts secreted various cytokines, including VEGF, HGF, TGFβ and bFGF. Moreover, ASCs–ADM conditioned medium notably stimulated the migration and proliferation of fibroblasts. In vivo, we established an excisional wound model in diabetic rats which received phosphate‐buffered saline (PBS), ADM or ASCs–ADM grafts, respectively. Our results demonstrated that implantation of ASCs–ADM significantly enhanced tissue regeneration and increased epithelialization, resulting in accelerated wound closure. Immunofluorescence analysis further indicated that capillary density was evidently increased in the ASCs–ADM group compared with the control or ADM group. In addition, western blot analysis showed that ASCs–ADM significantly increased the expression of angiogenic factors, which was consistent with in vitro data. Taken together, our results suggest that targeted delivery of ASCs via ADM scaffold accelerate diabetic wound healing through a paracrine mechanism, with enhanced granulation tissue formation and increased re‐epithelialization and neovascularization. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
56.
57.
Karande P Jain A Ergun K Kispersky V Mitragotri S 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(13):4688-4693
Chemical penetration enhancers (CPEs) are present in a large number of transdermal, dermatological, and cosmetic products to aid dermal absorption of curatives and aesthetics. This wide spectrum of use is based on only a handful of molecules, the majority of which belong to three to four typical chemical functionalities, sporadically introduced as CPEs in the last 50 years. Using >100 CPEs representing several chemical functionalities, we report on the fundamental mechanisms that determine the barrier disruption potential of CPEs and skin safety in their presence. Fourier transform infrared spectroscopy studies revealed that regardless of their chemical make-up, CPEs perturb the skin barrier via extraction or fluidization of lipid bilayers. Irritation response of CPEs, on the other hand, correlated with the denaturation of stratum corneum proteins, making it feasible to use protein conformation changes to map CPE safety in vitro. Most interestingly, the understanding of underlying molecular forces responsible for CPE safety and potency reveals inherent constraints that limit CPE performance. Reengineering this knowledge back into molecular structure, we designed >300 potential CPEs. These molecules were screened in silico and subsequently tested in vitro for molecular delivery. These molecules significantly broaden the repertoire of CPEs that can aid the design of optimized transdermal, dermatological, and cosmetic formulations in the future. 相似文献
58.
目的:探讨脱细胞真皮基质植入对Frey综合征的预防作用。方法:89例腮腺良性肿瘤手术病例分为实验组和对照组,实验组42例腮腺切除术后植入脱细胞真皮基质,对照组腮腺切除术后不植入脱细胞真皮基质,分别于术后12个月及24个月时复查对比两组患者Frey综合征发生率。结果:实验组术后12个月及24个月复查,Frey综合症发生率均低于对照组,发生率差异有统计学意义;两组患者Frey综合症发生率与腮腺肿块大小无明显相关。结论:近期观察显示,异种脱细胞真皮基质植入是一种简便有效的降低Frey综合症发生率的方法。 相似文献
59.
Kimberly Englert Katrina Ruedy Julie Coffey Kimberly Caswell Amy Steffen Lucy Levandoski for the Diabetes Research in Children Study Group 《Journal of diabetes science and technology》2014,8(4):745-751
Background:The purpose of this article is to describe challenges associated with successful use of continuous glucose monitoring (CGM) by young children with type 1 diabetes (T1D) and to detail the techniques and products used to improve the duration of sensor wear.Methods:The DirecNet Study Group conducted 2 studies in 169 children with T1D between the ages of 1 and 9 years who were instructed to wear a CGM device daily. Problems related to skin irritation and sensor adhesiveness in these young children presented challenges to daily use of the CGM. Study coordinators instituted a variety of techniques using commercially available products to attempt to overcome these problems.Results:Three primary factors that contributed to reduced CGM use were identified: the limited body surface area in smaller children, ambient temperature and humidity, as well as the type and duration of physical activity. Using supplemental products to minimize the impact of these factors resulted in improved adherence and reduced skin irritation.Conclusion:Achieving satisfactory adhesion of the CGM sensor and transmitter may involve finding the right supplemental product or combination of products through trial and error. Optimizing adhesion and minimizing skin irritation can significantly improve duration of use and tolerability of CGM devices by young children. 相似文献
60.
Páll Karlsson Carla Porretta‐Serapiglia Raffaella Lombardi Troels S. Jensen Giuseppe Lauria 《Journal of the peripheral nervous system : JPNS》2013,18(1):48-53
The aim of this study was to estimate dermal nerve fiber length (DNFL) using a stereological sampling technique in comparison with a previously reported manual estimation. DNFL was analyzed in skin punch biopsy specimens from 24 healthy volunteers and 18 patients with small fiber neuropathy (SFN) using global spatial sampling that yields unbiased and reliable length estimation. The estimation was carried out in 50‐µm biopsy sections after immunostaining with anti‐protein gene product (PGP) 9.5 antibodies. The length of the PGP9.5‐positive dermal nerves from the dermal–epidermal junction and 200 µm down was measured (DNFL mm?2). Results were compared with our previously reported manual method. Patients showed a significantly (p < 0.0001) lower DNFL (105 mm?2 ± 6.4 SD) than healthy subjects (246 mm?2 ± 8.39 SD). Moderate correlation with age was observed for both healthy subjects (Pearson's r = ?0.33) and patients (Pearson's r = ?0.59). A significant (p < 0.001) correlation between global spatial sampling and manual estimation was observed in both patients and healthy subjects (Pearson's r = 0.62 and 0.61, respectively). These findings provide further evidence on the reliability of dermal nerve morphometry in human skin and strengthen the hypothesis that dermal nerve fibers undergo significant degeneration in SFN. 相似文献