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11.
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on modal energy coefficients is proposed to detect troubled cells, where discontinuities exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR method. Numerical investigations show that the proposed subcell limiting strategy on unstructured quadrilateral meshes is robust in shock-capturing.  相似文献   
12.
目的  探讨Hsa-miR-4282在肝癌细胞系SMMC-7721中的表达及其对细胞生长的影响。方法 采用实时荧光定量PCR法检测Hsa-miR-4282在人正常肝上皮细胞系HL-7702和人肝癌细胞系MHCC97-H、SMMC-7721,以及 20例肝癌组织及其相应癌旁组织中的表达。采用瞬时转染法将Hsa-miR-4282 mimics(上调组)和Hsa-miR-4282 inhibitor(下调组)分别转染肝癌SMMC-7721细胞,上调组和下调组分别设置相应阴性对照组。转染后采用MTT法检测细胞增殖能力,平板克隆形成实验检测细胞克隆形成能力,流式细胞仪检测细胞凋亡能力。结果 Hsa-miR-4282在肝癌组织、肝癌细胞MHCC97-H及肝癌细胞SMMC-7721中的表达均低于癌旁组织及正常肝细胞HL-7702(P<0.05)。MTT实验结果显示,Hsa-miR-4282上调后肝癌SMMC-7721细胞的OD值低于其阴性对照组,而下调后OD值高于其阴性对照组 (P<0.05)。平板克隆形成实验显示,下调组的细胞克隆数高于其阴性对照组[(240±7) 个 vs (191±10) 个,P=0.005)],而上调组细胞克隆数低于基阴性对照组[(146±10) 个 vs (193±12) 个,P=0.013)]。流式细胞仪检测结果显示,Hsa-miR-4282上调组细胞凋亡率较其阴性对照组升高[(23.89±1.89)% vs(16.6±1.14)%,P=0.009)],下调组细胞凋亡率较期阴性对照组降低[(14.98±0.46)% vs (17.79±0.73)%,P=0.010]。结论 Hsa-miR-4282上调可抑制肝癌SMMC-7721细胞增殖,促进细胞凋亡,可能与肝癌的发病机制有关。  相似文献   
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目的了解华坪县健康人群麻疹抗体水平,发现工作薄弱地区和免疫空白人群,为实现消除麻疹的目标提供科学依据。方法采用分层抽样方法对华坪县8个乡镇不同年龄段健康人群开展麻疹抗体监测,采用间接酶联免疫吸附试验(ELISA间接法)检测血清麻疹Ig G抗体。结果 2013-2015年共检测1 106人,麻疹抗体总阳性率96.47%。其中,阳性率较低的是2014年(93.13%),人群是8~17月龄组(89.22%)。尚有新庄乡(89.92%)、船房乡(93.98%),通达乡(94.86%)3个乡镇麻疹抗体阳性低于95%。有免疫史者人群阳性率较无免疫史者高(χ~2=5.1830,P=0.023),男女性别间无差异。结论华坪县人群麻疹免疫效果较好,但存在免疫薄弱地区和免疫空白人群,应结合该监测结果,加强重点乡镇麻疹疫苗两剂次接种工作和抗体阴性人群的重新免疫接种。  相似文献   
15.
Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.

  相似文献   

16.
目的探讨脑卒中患者急性应激障碍发生现状及影响因素。方法采用斯坦福急性应激反应问卷对349例脑卒中住院患者进行调查。结果共163例(46.70%)患者发生急性应激障碍;Logistic回归分析结果显示,患者性格、是否存在偏瘫及是否吞咽功能障碍是脑卒中患者发生急性应激障碍的主要影响因素(P0.05,P0.01)。结论脑卒中患者急性应激障碍发生率较高,内向性格及存在偏瘫和吞咽功能障碍的患者更容易发生急性应激障碍。医护人员应及时为高危患者提供个体化治疗及预见性护理,防止脑卒中患者发生急性应激障碍。  相似文献   
17.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
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目的探讨家长健康素养与学龄前儿童心理行为问题的关系,为学龄前儿童心理行为问题早期干预提供参考。方法 2018年5-7月采用分层整群随机抽样的方法,抽取深圳市光明区13所幼儿园4 120名学龄前儿童及其家长,使用长处与困难问卷(SDQ)家长版和深圳市居民健康素养问卷分别对学龄前儿童心理行为问题及家长健康素养水平进行调查;采用非条件Logistic回归分析家长健康素养与儿童心理行为问题的关系。结果学龄前儿童心理行为问题检出率为34.9%(1 436/4 120)。其中困难总分6.5%、情绪问题5.6%、品行问题8.9%、多动注意不能13.4%、同伴交往问题14.4%、亲社会行为9.2%。男童和女童困难总分、情绪问题、品行问题、多动注意不能、同伴交往问题、亲社会行为检出率分别为7.3%和5.5%,4.8%和6.5%,9.7%和7.8%,15.5%和10.7%,15.8%和12.7%,11.1%和6.7%,差异有统计学意义(χ^2值分别为5.626,5.506,4.212,19.846,7.650,23.863,P<0.05)。多因素Logistic回归分析显示,家长健康素养(OR=1.294)、健康知识(OR=1.293)、健康行为(OR=1.412)及健康技能(OR=1.193)水平低是学龄前儿童心理行为问题产生的危险因素(P<0.05)。结论学龄前儿童心理行为问题发生率较高,问题突出,家长健康素养水平低是学龄前儿童心理行为问题的重要影响因素。  相似文献   
20.
Since the new round of health care reform in 2009, the vertical integration of hospitals and primary health institutions has become widely implemented in China as an efficient method for improving quality of primary care. This study aimed to answer the following questions: (a) What is the perceived quality of township health centres (THCs) under integration? (B) What differences could be observed among the three typical integration models, namely, private hospital-THC integration, public hospital-THC integration, and loose collaboration? Two rounds of cross-sectional surveys were conducted from November 2016 to June 2018. The Chinese version of the Primary Care Assessment Tool was used to evaluate perceived quality of sample THCs, and 1118 adult patients were interviewed in total. Multiple linear regressions were employed to compare the quality scores between two survey rounds and among different integration models after controlling for potential confounders. The results revealed that the quality of care significantly improved under private hospital-THC integration as observed by comparing two survey rounds, while no change or slight changes were observed in the other two models. The difference observed among the three models was that the perceived quality of THCs integrated with private hospitals was worse than that of THCs integrated with public hospitals and THCs under loose collaboration, while no significant difference was observed between public hospital-THC integration and loose collaboration. Increased attention should be given to highlighting the tight integration between hospitals and THCs and the different roles played by private and public hospitals in the current reform.  相似文献   
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