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101.
102.
Ziqing Li Shiming Yu Changhe Hou Yi Chen Yangchun Zhang Qiyi Zhai Bo Bai Puyi Sheng 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2014,24(2):179-186
Purpose
Both rotational acetabular osteotomy (RAO) and eccentric rotational acetabular osteotomy (ERAO) are effective procedures for young patients with developmental dysplasia of the hip. However, no comparative study of biomechanical changes has been reported following these two procedures. We therefore explored the stress changes on femoral head after RAO and ERAO under different load conditions.Materials and methods
Twelve female cadaveric hips without deformity were divided into RAO group and ERAO group. Stress value on femoral head was measured preoperatively and postoperatively after the vertical force was loaded on the cadaveric spine from 0 to 500 N. Stress change value was then calculated base on the measurements.Results
In the RAO group, preoperative stress increased when loading on spine became larger, but postoperative stress changed its increasing trend into decreasing when the load was greater than 200 N (turning point). Same phenomenon was found in the ERAO group (turning point was 300 N). However, the difference between preoperative and postoperative stress was not statistically significant in both RAO and ERAO groups. Stress change value from each procedure showed similar trends. With the load growth, stress change increased firstly and then decreased, but the difference between RAO and ERAO was not statistically significant.Conclusions
Both RAO and ERAO could correct the abnormal biomechanical effect of dysplastic hip; moreover, they may have similar biomechanical effects on femoral head, obtaining the same clinical outcomes. Non-biomechanical factors (surgical trauma, technical complexity, etc.) also play important roles in procedure selection. 相似文献103.
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Carbon fiber reinforced thermosetting polyimide (CF/TSPI) composites were interleaved with thermally stable thermoplastic polyimide (TPPI) fiber veils in order to improve the interlaminar fracture toughness without sacrificing the heat resistance. Both of the mode I and mode II interlaminar fracture toughness (GIC and GIIC) for the untoughened laminate and TPPI fiber veils interleaved laminates were characterized by the double cantilever beam (DCB) test and end notch flexure (ENF) test, respectively. It is found that the TPPI fiber veils interleaved laminates exhibit extremely increased fracture toughness than the untoughened one. Moreover, the areal density of TPPI greatly affected the fracture toughness of laminates. A maximum improvement up to 179% and 132% on GIC and GIIC is obtained for 15 gsm fiber veils interleaved laminate, which contributes to the existence of bicontinuous TPPI/TSPI structure in the interlayer according to the fractography analysis. The interlaminar fracture behavior at elevated temperatures for 15 gsm fiber veils interleaved laminate were also investigated. The results indicated that the introduction of thermally stable TPPI fiber veils could enhance the fracture toughness of CF/TSPI composites by exceeding 200% as compared to the untoughened one even as tested at 250 °C. 相似文献
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文题释义:玻璃化冷冻保存:是利用这些高浓度的低温保护剂组合成玻璃化冻存液,通过与水分子发生强烈的水合作用,增加溶液黏性,降低冰晶形成速度,从而使细胞在快速降温或复温过程中得以保护。
玻璃化:对于非晶高分子,当高分子通过降温从高弹态转变为玻璃态,或者通过升温从玻璃态转变为高弹态的过程称之为玻璃化转变,发生玻璃化转变的温度叫玻璃化转变温度。对于结晶高分子,玻璃化转变是指其非晶部分所发生的由高弹态向玻璃态(或者玻璃态向高弹态)的转变。因此,玻璃化转变是高分子中普遍存在的现象。但是玻璃化转变现象并不局限于高分子,一些小分子化合物也存在玻璃化转变。
背景:玻璃化冷冻保存是一种应用前途广阔的低温冷冻方法,通过使用高浓度的玻璃化冻存试剂将生物材料进行玻璃态转变,从而实现活性保存。
目的:就玻璃化冻存的生物学原理及玻璃化冻存试剂的分类,卵巢、皮肤与角膜等医学组织标本的玻璃化冻存进行综述。
方法:以“tissue;vitrification;cryopreservation”为英文检索词;“组织;玻璃化;冷冻保存”为中文检索词,检索1994年1月至2019年10月 PubMed 数据库及万方医学网相关文献。按照纳入与排除标准筛选后,对最终纳入的45篇文献进行归纳总结。
结果与结论:玻璃化冻存可以防止细胞内外冰晶形成,避免了冰晶给细胞带来的多种损伤,有效保留了细胞的生物活性与基本功能。玻璃化冻存试剂主要分为渗透性和非渗透性2种,其操作简便、高效,唯一的缺点是高浓度的冻存试剂对细胞具有一定的毒性损伤。为了降低对组织整体损伤风险,可以混合使用多种低毒冻存试剂。目前玻璃化冻存技术已经成功应用于多种细胞,但组织冻存的技术难题尚未完全解决。
ORCID: 0000-0003-0140-9935(张源)
中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程 相似文献
108.
Tiantian Zhang Qianqian Fu Dalin Gao Liyan Ge Lin Sun Qiongli Zhai 《Pathology, research and practice》2014
Epstein-Barr virus (EBV) is a ubiquitous γ-herpes virus that asymptomatically infects more than 90% of the world's population. The exact mechanism of EBV in oncogenesis is an area of active debate. However, EBV has been implicated in the pathogenesis of several kinds of lymphomas and lymphoproliferative disorders, including B-, T- and NK-cell derived. Subsequent studies have proven that the EBV gene expression product plays an activating and/or promoting role on lymphomagenesis, and paves the way for novel cellular therapies of EBV-associated lymphomas. This review concentrates on the pathology, morphology, treatment and prognosis of EBV-associated lymphomas in the 2008 WHO classification of tumors of hematopoietic and lymphoma tissues. 相似文献
109.
Jordan A Roberts Lindsay Waters Jae Y Ro Qihui Jim Zhai 《International journal of clinical and experimental pathology》2014,7(2):792-796
An accurate distinction between deep muscularis propria invasion versus subserosal invasion by colonic adenocarcinoma is essential for the accurate staging of cancer and subsequent optimal patient management. However, problems may arise in pathologic staging when extensive desmoplasia blurs the junction between deep muscularis propria and subserosal fibroadipose tissue. To address this issue, forty-three (43) cases of colonic adenocarcinoma resections from 2007-2009 at The Methodist Hospital in Houston, TX were reviewed. These cases were selected to address possible challenges in differentiating deep muscularis propria invasion from superficial subserosal invasion based on H&E staining alone. Immunohistochemical staining using smooth muscle actin (SMA), smoothelin, and caldesmon were performed on 51 cases: 8 cases of pT1 tumors (used mainly as control); 12 pT2 tumors; and 31 pT3 tumors. All 51 (100%) had diffuse, strong (3+) immunoreactivity for caldesmon and smoothelin in the muscularis propria with a granular cytoplasmic staining pattern. However, the desmoplastic areas of these tumors, composed of spindled fibroblasts and myofibroblasts, showed negative immunostaining for caldesmon and smoothelin (0/35). SMA strongly stained the muscularis propria and weakly (1+) or moderately (2+) stained the spindled fibroblasts in the desmoplastic areas (the latter presumably because of myofibroblastic differentiation). Compared to SMA, caldesmon and smoothelin are more specific stains that allow better delineation of the muscularis propria from the desmoplastic stromal reaction which provides a critical aide for proper staging of colonic adenocarcinoma and subsequent patient care. 相似文献
110.
Glycoprotein non-metastatic protein B (GPNMB) promotes bone metastasis (BM) in various types of cancer. However, GPNMB expression and its function in patients with renal cell carcinoma (RCC) and BM is still unknown. Therefore, the clinical significance of GPNMB and its biological function in RCC with BM was investigated in the present study. A total of 31 patients with RCC and BM were retrospectively collected. The association between GPNMB protein expression level on the primary tumor and the clinicopathological characteristics of the patients was analyzed. Kaplan-Meier analysis was used to investigate the association between GPNMB expression and the prognosis of the patients. The effects of GPNMB inhibition on cell proliferation, migration and invasion in RCC cells were investigated using short hairpin (sh)RNA. High GPNMB expression level was significantly associated with the number (P=0.001) and the extent of BM (P=0.001), Fuhrman grade (P=0.037), and ERK expression level (P=0.003) of the primary tumor. In addition, GPNMB overexpression was significantly associated with poor prognosis with respect to overall survival time (P=0.001). Furthermore, a specific shRNA sequence targeting the GPNMB gene was constructed and transduced into the ACHN cell line, using a lentivirus vector to obtain a stable cell line with low mRNA expression level of GPNMB. Low GPNMB expression level inhibited RCC cell proliferation, which was measured using a Cell Counting Kit-8 assay. Cell migration and invasion ability was significantly decreased in GPNMB knockdown RCC cells compared with that in cells transduced with the negative control shRNA. In addition, the protein expression levels of phosphorylated ERK were lower in the GPNMB shRNA-transduced ACHN cells compared with those in the control cells. Therefore, these results suggested that GPNMB plays an important role in tumor progression in RCC with BM. Furthermore, it might serve as a predictive marker for BM and as a poor prognostic factor in RCC with BM. GPNMB downregulation suppressed the proliferation, migration and invasion of the RCC cells, which may be mediated through the inhibition of the ERK signaling pathway. 相似文献