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61.
62.
目的探讨胫前动脉踝上穿支皮瓣修复足踝部软组织缺损的临床疗效。方法回顾性研究2018年4月至2019年6月采用胫前动脉踝上穿支皮瓣修复足踝部软组织缺损19例的资料,其中男11例,女8例;年龄为21~75岁,平均39岁。根据前踝上穿支皮瓣解剖学基础,按照足踝部软组织缺损大小和形状,在小腿下端前外侧设计并切取皮瓣转位修复创面。切取胫前动脉踝上穿支皮瓣面积为6.0 cm×5.0 cm^14.0 cm×8.0 cm,均为带蒂皮瓣转位。根据皮瓣成活、感染控制、弹性色泽、外观形态、供区瘢痕、皮肤感觉、患者认可等情况,对患者足踝部软组织缺损的修复情况进行综合评价。结果本组19例皮瓣全部成活,软组织缺损、肌腱、骨质及钢板外露均得以修复。供区均I期愈合。术后门诊随访2~16个月,皮瓣血运良好,颜色接近周围正常皮肤,臃肿不明显,患者对外观表示满意;供区皮片愈合良好,无明显增生、挛缩及溃疡,踝关节功能良好。结论胫前动脉踝上穿支皮瓣是修复足踝部软组织缺损较为理想的方法之一,手术操作简便,穿支较恒定,血供可靠,具有一定的临床应用价值。 相似文献
63.
《The ocular surface》2020,18(4):901-911
PurposeThe long-term success of visual rehabilitation in patients with severe conjunctival scarring is reliant on the reconstruction of the conjunctiva with a suitable substitute. The purpose of this study is the development and investigation of a re-epithelialized conjunctival substitute based on porcine decellularized conjunctiva (PDC).MethodsPDC was re-epithelialized either with pre-expanded human conjunctival epithelial cells (PDC + HCEC) or with a human conjunctival explant placed directly on PDC (PDC + HCEx). Histology and immunohistochemistry were performed to evaluate epithelial thickness, proliferation (Ki67), apoptosis (Caspase 3), goblet cells (MUC5AC), and progenitor cells (CK15, ΔNp63, ABCG2). The superior construct (PDC + HCEx) was transplanted into a conjunctival defect of a rabbit (n = 6). Lissamine green staining verified the epithelialization in vivo. Orbital tissue was exenterated on day 10 and processed for histological and immunohistochemical analysis to examine the engrafted PDC + HCEx. A human-specific antibody was used to detect the transplanted cells.ResultsFrom day-14 in vitro onward, a significantly thicker epithelium and greater number of cells expressing Ki67, CK15, ΔNp63, and ABCG2 were noted for PDC + HCEx versus PDC + HCEC. MUC5AC-positive cells were found only in PDC + HCEx. The PDC + HCEx-grafted rabbit conjunctivas were lissamine-negative during the evaluation period, indicating epithelial integrity. Engrafted PDC + HCEx showed preserved progenitor cell properties and an increased number of goblet cells comparable to those of native conjunctiva.ConclusionPlacing and culturing a human conjunctival explant directly on PDC (PDC + HCEx) enables the generation of a stable, stratified, goblet cell-rich construct that could provide a promising alternative conjunctival substitute for patients with extensive conjunctival stem and goblet cell loss. 相似文献
64.
Marie Ohata Susumu Fujiwara Ai Yoshioka Hiroshi Nagai Shintaro Sugita Nozomi Yamano Yusuke Inoue Chikako Nishigori 《Pediatric dermatology》2019,36(6):997-998
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy. 相似文献
65.
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67.
S. Xing X. Zhang J. H. Liu X. Huang P. Zhou 《Clinical and experimental immunology》2019,195(1):121-131
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT. 相似文献
68.
69.
Objective: To investigate the ability of contrast enhancement patterns of contrast-enhanced ultrasound in differentiating benign and malignant soft tissue tumours. 相似文献
70.
Rena Fushiki Kotoe Mayahara Mai Ogawa Yasuyo Takahashi Yoko Karasawa Niina Tsurumachi 《Connective tissue research》2015,56(4):336-341
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2. 相似文献