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991.
Oral propranolol is the first‐line therapy for infantile hemangioma (IH), but its mechanism of action remains unclear. The aim of this study was to evaluate the change in serum vascular endothelial growth factor (VEGF) levels in patients with IH who underwent propranolol treatment. The study included 22 patients with IH receiving propranolol treatment. At three time points—before treatment and 1 and 3 months after treatment—blood samples were examined by enzyme‐linked immunosorbent assay for serum VEGF expression. The mean serum VEGF concentration in children with proliferative hemangiomas was 395.0 ± 176.7 pg/mL, approximately twice as high as in patients with venous malformations (mean 170.7 pg/mL) and in healthy controls (204.8 pg/mL, p = 0.006). After 1 month of propranolol treatment, the level had fallen 21.6% (p = 0.003), although the downward trend was less obvious after 3 months of treatment (18.0%, p = 0.63). VEGF expression correlated significantly with the lesion size (correlation coefficient [R] = 0.43, p = 0.046), whereas no correlation was observed with age (R = 0.13, p = 0.56). Serum VEGF levels were higher in patients with IH and fell after 1 month of oral propranolol treatment. Similar results, although less pronounced, were found after 3 months of treatment. Lesion volume and serum level of VEGF were significantly correlated.  相似文献   
992.
BackgroundNeuropathic pain is a multifaceted and ubiquitous disease across the globe. Mood disorders, such as anxiety and depression, are frequently observed in patients suffering from neuropathic pain. Both neuropathic pain and comorbid mood disorders seriously impact quality of life. Accumulated evidence shows that activation of the NOD-like receptor protein 3 (NLRP3) inflammasome is involved in the neuroinflammatory pathogenesis of neuropathic pain, anxiety, and depression. However, the role of the NLRP3 inflammasome in the pathological process of anxiety and depression under the neuropathic pain state has not been fully described. Albiflorin, a monoterpene glycoside, may be a potential regulator of the NLRP3 inflammasome, but it is not clear whether albiflorin relates to NLRP3 inflammasome activation.MethodsWe used a systematic pharmacological method to confirm whether the activation of the NLRP3 inflammasome in the hippocampus was involved in the development of neuropathic pain associated with mood disorders and whether albiflorin could be an effective treatment for these symptoms.ResultsThe NLRP3 inflammasome contributed to the neuropathic pain and comorbid anxiety and depression-like behaviors induced by chronic constriction injury of the sciatic nerve, and albiflorin may relieve these symptoms via inhibition of the NLRP3 inflammasome activity. Moreover, albiflorin enhanced the translocation of the nuclear factor erythroid 2-related factor 2 into the nucleus and suppressed nuclear factor-kappa B activity in the hippocampus.ConclusionsAlbiflorin, as a potential therapeutic agent, might greatly improve the overall symptoms of neuropathic pain.  相似文献   
993.
中国胰腺癌发病趋势分析和预测   总被引:3,自引:1,他引:2       下载免费PDF全文
目的利用中国肿瘤登记地区1998-2007年胰腺癌发病登记数据分析胰腺癌发病趋势,并预测2008--2015年中国胰腺癌的发病情况。方法计算各年份胰腺癌的粗发病率,直接法计算中国人口标准化率,采用JoinPoint软件对中国肿瘤登记地区1998-2007年胰腺癌发病数据进行趋势分析,计算年度平均变化率。应用贝叶斯年龄一时期一队列模型对数据进行拟合,估计年龄、时期、队列参数效应并预测2008-2015年全国胰腺癌发病情况。结果1998-2007年城市男性粗发病率每年以1.86%的比例上升,中国人口标准化率上升趋势不明显;女性粗发病率每年上升2.1%,中国人口标准化率上升趋势不明显。农村男性粗发病率每年上升7.54%,中国人口标准化率每年上升4.82%;女性分别上升7.83%和5.48%。预测模型显示年龄效应、时期效应和队列效应均在胰腺癌发病中起重要作用。估计2015年新发胰腺癌103 428例,其中男性60 500例,女性42 928例,较2008年增加15 277例。结论中国胰腺癌发病率呈上升趋势,其中农村地区上升明显,城市地区上升速度略缓,到2015年总体上升趋势有所减缓,但短期内胰腺癌仍然是主要癌症。  相似文献   
994.
目的构建准确、有效、易操作的研究生生源质量评价体系,促进研究生教育健康发展。 方法在利益相关者调查、文献研究及专家访谈的基础上,初步确定硕士研究生生源质量评价指标体系的一级、二级指标,运用德尔菲法进行两轮专家咨询最终确定硕士研究生生源质量评价指标,运用层次分析法计算评价指标权重。 结果专家熟悉程度为0.8657、0.8648,判断依据为 0.7457、0.7484,权威系数为 0.8057、0.8314,Kendall协调系数为 0.125、0.406( P<0.001)。确定硕士研究生生源质量评价指标包括 4项一级指标、14项二级指标。一级指标为成绩指标、背景结构、专业适配、综合素质,权重分别为 0.42、0.23、0.23、0.12,判断矩阵的一致性比例(CR)为 0.004,二级指标判断矩阵的(CR)分别为0.017、0.018、0.018、0。 结论运用德尔菲法和层次分析法构建的硕士研究生生源质量评价指标体系及其权重较为科学,结果可信,可对研究生生源质量进行科学的诊断性评估,为研究生教育的培养、就业跟踪评价奠定了重要的基础作用。  相似文献   
995.
996.
Axonal regeneration plays an important role in functional recovery after nervous system damage. However, after axonal injury in mammals, regeneration is often poor. The deletion of Krüppel-like factor-4 (Klf4) has been shown to promote axonal regeneration in retinal ganglion cells. However, the effects of Klf4 deletion on the corticospinal tract and peripheral nervous system are unknown. In this study, using a mouse model of sciatic nerve injury, we show that the expression of Klf4 in dorsal root ganglion sensory neurons was significantly reduced after peripheral axotomy, suggesting that the regeneration of the sciatic nerve is associated with Klf4. In vitro, dorsal root ganglion sensory neurons with Klf4 knockout exhibited significantly enhanced axonal regeneration. Furthermore, the regeneration of the sciatic nerve was enhanced in vivo following Klf4 knockout. Finally, AAV-Cre virus was used to knockout the Klf4 gene in the cortex. The deletion of Klf4 enhanced regeneration of the corticospinal tract in mice with spinal cord injury. Together, our findings suggest that regulating KLF4 activity in neurons is a potential strategy for promoting axonal regeneration and functional recovery after nervous system injury. This study was approved by the Animal Ethics Committee at Soochow University, China (approval No. SUDA20200316A01).

Chinese Library Classification No.R456; R741; Q344+.14  相似文献   
997.
998.
Brain arterial aneurysms are localised dilatation in the wall of cerebral arteries that are common among adult population and associated with high incidence of morbidity and mortality. Using flow diverter stent alone to treat cerebral aneurysm is recognized as a safe and effective method. However, flow diverter stents currently available have limitations due to their braided structures. In this paper a novel flow diverter stent is proposed. It is made out of nitinol tubes that provide adequate radial stiffness and tailored surface coverage to overcome problems of currently available braided stents while retaining low porosity and excellent longitudinal flexibility. Finite element analysis using Abaqus has been conducted to investigate radial stiffness, longitudinal flexibility, and maximum strain during packaging of a series of novel stent designs with varied geometric parameters. Results show that porosity below 70% can be achieved and provides radial stiffness and longitudinal flexibility comparable to those of the Neuroform stent that is commonly used for stent assisted coiling. The novel flow diverter has showed great potential for direct treatment of cerebral aneurysms.  相似文献   
999.
1000.
Esophageal squamous cell carcinoma (ESCC) is widely known as a highly fatal cancer, and thus it is important to identify tumor-specific and radiosensitivity-specific markers in ESCC. B cell translocation gene 2 (BTG2) has been considered a novel tumor suppressor gene or radiotherapy sensitivity-associated gene. However, the relationship between BTG2 and ESCC development and radiotherapy sensitivity is uncertain. The present study aims to explore the expression and clinical significance of B cell translocation gene 2 (BTG2) in ESCC by analyzing the RNAseq data from the TCGA and immunohistochemical staining of ESCC samples. We found that the level of BTG2 mRNA was significantly decreased in ESCC patients, and further decreased significantly in radiotherapy resistant patients compared to sensitive patients. The positive expression rate of BTG2 protein was 56.0% (103/184) in 184 ESCC tissue samples and 84.0% (42/50) in normal esophageal mucosal samples, respectively. The positive ratios of BTG2 expression in radiotherapy-sensitive group and radiotherapy resistant group were 57.9% (22/38) and 23.5% (4/17), respectively. Furthermore, the analysis indicates that the expression level of BTG2 significantly correlated with lymph node metastasis and clinical staging in ESCC patients. A multivariate analysis with Cox regression model showed that BTG2 level was an independent risk factor affecting the prognosis of ESCC patients. Above all, the downregulation of BTG2 may be used as a molecular marker to identify and predict ESCC progression and radiosensitivity.  相似文献   
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