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1.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
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
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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
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Susumu Shibasaki Koichi Suda Masaya Nakauchi Kenichi Nakamura Kenji Kikuchi Kazuki Inaba Ichiro Uyama 《World journal of gastroenterology : WJG》2020,26(11):1172-1184
BACKGROUND Minimally invasive surgery for gastric cancer(GC) has gained widespread use as a safe curative procedure especially for early GC.AIM To determine risk factors for postoperative complications after minimally invasive gastrectomy for GC.METHODS Between January 2009 and June 2019, 1716 consecutive patients were referred to our division for primary GC. Among them, 1401 patients who were diagnosed with both clinical and pathological Stage Ⅲ or lower GC and underwent robotic gastrectomy(RG) or laparoscopic gastrectomy(LG) were enrolled. Retrospective chart review and multivariate analysis were performed for identifying risk factors for postoperative morbidity.RESULTS Morbidity following minimally invasive gastrectomy was observed in 7.5% of the patients. Multivariate analyses demonstrated that non-robotic minimally invasive surgery, male gender, and an operative time of ≥ 360 min were significant independent risk factors for morbidity. Therefore, morbidity was compared between RG and LG. Accordingly, propensity-matched cohort analysis revealed that the RG group had significantly fewer intra-abdominal infectious complications than the LG group(2.5% vs 5.9%, respectively; P = 0.038), while no significant differences were noted for other local or systemic complications.Multivariate analyses of the propensity-matched cohort revealed that non-robotic minimally invasive surgery [odds ratio = 2.463(1.070–5.682); P = 0.034] was a significant independent risk factor for intra-abdominal infectious complications.CONCLUSION The findings showed that robotic surgery might improve short-term outcomes following minimally invasive radical gastrectomy by reducing intra-abdominal infectious complications. 相似文献
6.
目的探讨改良双腔球囊导管在插管失败的输卵管阻塞介入再通术中的应用价值。方法回顾45例输卵管阻塞性不孕患者,应用常规法行介入再通术,其中输卵管开口插管失败采用改良双腔球囊导管行介入再通,统计分析常规法组与联合改良双腔球囊导管法组(联合法组)的输卵管开口插管成功率、输卵管阻塞的开通率。结果输卵管阻塞性不孕患者45例,共阻塞输卵管90条,采用常规法输卵管开口插管成功32条,其中开通成功31条,插管成功率为35.56%,开通率96.88%。采用联合法输卵管开口插管成功90条,输卵管开通83条,插管成功率为100%,开通率92.22%,7条输卵管因阻塞病情严重无法开通,其中双侧均未能开通1例。所有患者术中均无严重并发症发生。随访12个月,妊娠率48.65%。常规法组与联合法组输卵管开口插管成功率差异具有统计学意义(χ^2=85.574,P=0.000),而输卵管开通率差异无统计学意义(χ^2=0.248,P=0.619)。结论对于常规法输卵管开口插管失败者,采用联合改良双腔球囊导管可提高输卵管开口插管成功率。采用改良双腔球囊导管介入再通与常规法开通效果相当,可作为常规介入再通输卵管开口插管失败的备选方案。 相似文献
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《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes. 相似文献
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《Biomaterials》2015
The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration. 相似文献
10.
Gastro-oesophageal reflux disease (GORD) is symptomatic reflux of gastric contents into the oesophagus. Factors predisposing to GORD are loss of the physiological antireflux barrier and anatomic abnormalities of the oesophagus or diaphragm. Conservative measures and medical management results in resolution of symptoms in a majority of children. Surgery is indicated in the event of failure of medical management or severe complications. Surgical procedures include open or laparoscopic fundoplication in children with normal neurology; fundoplication with or without vagotomy and pyloroplasty; surgical feeding jejunostomy and oesophago-gastric dissociation in the severely neurologically impaired children. 相似文献