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91.
Mechanical force plays a pivotal role in the pathogenesis of hypertrophic scar (HTS). Dermal fibroblasts and myofibroblasts are the key cells involved in HTS. Myofibroblasts in HTS possess different biochemical and biophysical characteristics by which myofibroblasts are often distinguished from fibroblasts. The role of mechanotransducers outside the nucleus in the pathogenesis of HTS has been reported in many studies. However, the role of Nesprin‐2 in HTS is not clear. Hence, we aim to construct a cell model of HTS and explore the role of Nesprin‐2 in this process. Myofibroblasts and fibroblasts were isolated from HTS and healthy skin tissues of the same patient. Fibroblasts were exposed to cyclic stretch with 10% magnitude and a frequency of 0.1 Hz for 3 days, 5 days, and 7 days, respectively. After the cell model was confirmed, fibroblasts transfected with siRNA targeting human Nesprin‐2 were exposed to cyclic stretch. The mechanical behaviour and biochemical reaction of the dermal fibroblasts were analysed. The stretched fibroblasts at day 5 showed the same mechanotransductive and biochemical features as unstretched myofibroblasts. Mechanical strain could induce the myofibroblasts differentiation and a cell model of HTS was established successfully at day 5. The expressions of lamin A/C, alpha‐smooth muscle actin, transforming growth factor beta 1, and collagen type I in fibroblasts were reduced by the silencing of Nesprin‐2. Mechanical strain could induce the myofibroblasts differentiation and silencing of Nesprin‐2 could block the mechanical stimulation of terminal myofibroblasts differentiation. Nesprin‐2 might be a potential target to treat the HTS.  相似文献   
92.
Background and ObjectiveThe incidence of incision infection after lung transplantation is prominently high which affect the prognosis. Summarizing the risk factors related to incision infection after lung transplantation contribute to the control of incision infection by pre-controlling the risk factors. The objective is to summarize risk factors related to wound infection after lung transplantation.MethodsPubMed was used to research the literature relating to the risk factors to incision infection after lung transplantation through 1990 to 2022. The retrieval strategy were Medical Subject Heading (MeSH) terms combined entry terms. Two researchers conducted the literature retrieval independently. Two researchers independently evaluate the quality of the literature and summarize the indicators.Key Content and FindingsA total of 98 researches were collected from PubMed and 8 articles described the related risk factors of incision infection after lung transplantation. All of the 8 articles were retrospective studies, of which 4 articles were grouped by the delayed chest closure (DCC) execution and the other 4 articles were grouped by the surgical site infection (SSI) occurred. Two articles performed multivariate regression analysis to determine the independent risk factors of SSI after lung transplantation and the other 6 articles compared the SSI rate in different patients population. The integrated results showed that bronchoalveolar lavages (BALs), smoking status, body mass index (BMI), diabetes, operation duration, thoracic drainage tube placement time and DCC were related to the SSI after lung transplantation.ConclusionsBALs, smoking status, BMI, diabetes, operation duration, thoracic drainage tube placement time and DCC were related to the SSI after lung transplantation.  相似文献   
93.
This paper aims to investigate the fatigue cracking evolution of cold recycled asphalt mixtures with asphalt emulsion (CRME) under different curing times. The fatigue cracking model of CRME based on damage mechanics and fracture mechanics was analyzed according to the fatigue loading curve. Firstly, the fatigue cracking evolution of CRME was studied through an SCB strength test and SCB fatigue test. Then, the fatigue damage mechanics were used to establish a nonlinear fatigue cracking model, and the damage degree of CRME at the initial cracking point was determined. The Paris formula was used to characterize the law of fatigue crack propagation. Finally, the microstructure of CRME was observed by scanning electron microscopy (SEM) with the backscattering method. The results indicate that the initial cracking point appears at around 60% of the fatigue life according to the SCB fatigue test by means of image analysis. The damage variable was obtained through the cracking model, and the value of the damage variable was determined as 0.06–0.17 at the initial cracking point. In addition, the Paris formula showed that the crack growth of CRME can be reflected by the stress intensity factor and correlative parameters. Moreover, cement hydration products were mixed with the asphalt membrane to form a denser spatial structure during the curing process, which may provide higher fatigue performance of CRME. This research may provide a theoretical reference for studying the fatigue cracking behavior of CRME.  相似文献   
94.
Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials.  相似文献   
95.
为了观察人工组织神经移植物对大鼠坐骨神经非新鲜损伤的修复作用。我们在成年SD大鼠左侧股中部切除部分坐骨神经制造神经缺损模型。15d后,实验组(9只)用人工组织神经移植物修复神经缺损,自体神经修复作为阳性对照(6只),保持神经缺损为阴性对照(6只)。第二次手术后3个月,电生理学、形态学结果显示实验组的再生神经虽略差于自体对照组,但明显优于缺损对照组,腓肠肌的萎缩形态学指标变化则较接近自体对照组。实验结果表明人工组织神经移植物对已缺损15d的大鼠周围神经具有较好修复作用。  相似文献   
96.
目的:经典1型糖尿病(type 1 diabetes mellitus,T1DM)患者由于胰岛β细胞破坏、胰岛素绝对缺乏,需终身依赖外源性胰岛素治疗。中国糖尿病患儿中T1DM约占90%,发病率快速增加且低龄化严重。流行病学研究显示中国患儿平均糖化血红蛋白(glycated haemoglobin,HbA1c)整体偏高、达标率低。良好的血糖管理是糖尿病治疗的重点,维持血糖在目标范围内可阻止或延缓T1DM患者慢性血管并发症。本研究旨在利用扫描式葡萄糖监测系统(flash glucose monitoring system,FGMS)了解湖南省和河南省T1DM患儿的血糖控制情况,分析该群体血糖波动的影响因素。方法:选择2017年8月至2020年8月于两省16所医院内分泌科就诊的T1DM患儿215例,年龄≤14岁,均佩戴FGMS采集血糖数据,分析HbA1c、病程和葡萄糖扫描频率与血糖波动的相关性;根据患儿病程、HbA1c、葡萄糖扫描频率及胰岛素注射方式等因素进行分组比较。结果:HbA1c、病程与平均血糖、血糖标准差、平均血糖波动幅度(mean amplitude of glucose excu...  相似文献   
97.
印度新专利法的实行对医药企业的影响   总被引:1,自引:0,他引:1  
冯国忠  夏莹 《上海医药》2007,28(4):150-153
印度和我国一样都是发展中国家,人口众多,在医药领域既有很多相似之处,又存在激烈竞争:首先,从地理、人口、经济发展等方面看,中印两国国情比较相近,两国的制药产业也有惊人的相似之处(成本低廉,药品可获得性高);大部分企业仍处于低水平重复仿制阶段;研发力量较为薄弱,仿制药比  相似文献   
98.
目的 探讨长链非编码RNA(LncRNA)尿酸盐水解酶假基因(URAHP)在子痫前期胎盘组织中的异常表达及其对滋养层细胞增生、侵袭的影响.方法 选取子痫前期及正常孕妇胎盘组织6例,其中PE组纳入子痫前期患者3例,对照组纳入正常妊娠孕妇3例.筛选2组差异表达LncRNA和miRNA;分析LncRNA URAHP在2组胎盘...  相似文献   
99.
This study aims to analyze the characteristics of idiopathic membranous nephropathy (iMN) with nondiabetic urine glucose during the follow-up. We retrospectively analyzed the data of 1313 patients who were diagnosed iMN. The prevalence of nondiabetic urine glucose during follow-up was 10.89%. There were significant differences between the patients with nondiabetic urine glucose and those without urine glucose in gender, hypertension ratio, proteinuria, N-acetyl-β-glucosaminidase, retinol binding protein, serum albumin, serum creatinine (Scr), cholesterol, triglyceride and positive anti-phospholipase A2 receptor antibody ratio, glomerular sclerosis ratio, acute and chronic tubular injury lesion at baseline. To exclude the influence of the baseline proteinuria and Scr, case control sampling of urine glucose negative patients was applied according to gender, baseline proteinuria and Scr. The proteinuria nonremission (NR) ratio was 45.83 versus 12.50% of the urine glucose positive group and case control group. Partial remission (PR) ratio of the two groups was 36.46 versus 23.96% and complete remission (CR) ratio was 19.79% versus 63.54%, respectively. Patients with urine glucose had higher risk of 50% estimated glomerular filtration rate (eGFR) reduction. Cox regression showed that urine glucose and baseline Scr were risk factors of 50% reduction of eGFR. Urine glucose remission ratio of the patients with proteinuria NR, PR, and CR was 13.33, 56.25, and 94.73% (p < 0.005). Patients who got urine glucose remission also had better renal survival. In conclusion, non-diabetic urine glucose was closely related to proteinuria. It could be applied as a tubular injury marker to predict renal function.  相似文献   
100.
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