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1.
Guoliang Zhang & Tao Xiong 《Communications In Computational Physics》2022,32(1):126-155
We propose a high order finite difference linear scheme combined with a
high order bound preserving maximum-principle-preserving (MPP) flux limiter to
solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less
costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux
limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear
and WENO type schemes, with and without the MPP flux limiter, will demonstrate the
good performance of our proposed approach. 相似文献
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新生儿呼吸窘迫综合征合并呼吸机相关性肺炎患儿死亡相关因素Logistic回归分析 总被引:1,自引:0,他引:1
5.
目的:建立高效液相色谱-荧光检测法测定性早熟女童血浆中双酚A和4-壬基酚含量的方法。方法:采用Shim-pack VP-ODS C18色谱柱(150 mm×4.6 mm,5 μm),流动相为乙腈∶水=70∶30,流速1 mL/min,柱温30 ℃,检测激发波长275 nm,发射波长315 nm,外标法定量检测血浆中双酚A和4-壬基酚含量。结果:双酚A和4-壬基酚分别在1.45~5 937.50 ng/mL (r2=0.999 9,n=7),1.53~6 250.00 ng/mL(r2=0.998 8,n=7)范围内线性关系良好;日内、日间RSD均<7.83%,方法回收率均>94.6%。结论:本法简便、快速、灵敏、准确,适用于同时测定性早熟女童血浆中双酚A和4-壬基酚的含量和临床血样常规检测。 相似文献
6.
麦芽4个化学部位通过多巴胺D2受体对产后缺乳模型大鼠催乳作用研究 总被引:1,自引:0,他引:1
目的基于多巴胺D2受体(DRD2),考察小剂量麦芽4个化学部位的催乳作用,初步探讨小剂量麦芽生物碱对产后缺乳模型大鼠泌乳素(PRL)分泌的调节机制。方法采用ig甲磺酸溴隐亭方法制备缺乳大鼠模型,造模成功后,各给药组均ig给予相应的药物,应用ELISA法检测各组大鼠血清PRL、雌二醇(E_2)、孕酮(P)水平;HE染色观察各组大鼠乳腺组织病理改变;采用实时荧光定量PCR(qRT-PCR)法检测各组大鼠脑垂体中泌乳素受体及DRD2 mRNA表达。结果与对照组比较,模型组大鼠血清中PRL、P及E_2水平、脑垂体PRL mRNA表达水平显著降低;脑垂体DRD2 mRNA表达水平显著升高。与模型组比较,麦芽总生物碱组大鼠乳腺小叶体积明显增加,导管明显扩张,且导管及腺泡内含有大量乳汁。麦芽总生物碱明显增加模型大鼠血清中PRL、P、E_2水平及脑垂体PRL mRNA表达水平,降低脑垂体DRD2 mRNA表达水平。结论麦芽催乳的主要药效物质为总生物碱,其作用机制可能与促进PRL分泌,增加脑垂体PRL受体、降低DRD2 mRNA表达水平有关。 相似文献
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He Hongguang Huang Yiyun Zeng Chun Wu Chaoqing Ye Kun Xiong Lijia Peng Xiaomei 《中华肾脏病杂志》2019,35(1):9-17
Objective To investigate the predictive factors affecting the efficacy of cyclophosphamide (CTX) combined with glucocorticoids in the treatment of idiopathic membranous nephropathy (IMN), and to evaluate the efficacy of calcineurin inhibitor (CNI) adjustment due to poor treatment. Methods A retrospective cohort study was conducted. Two hundreds and twenty-eight patients with IMN diagnosed by renal biopsy in the People's Hospital of Guangxi Zhuang Autonomous Region from January 1, 2007 to December 1, 2016 were enrolled. All subjects were treated with CTX in combination with glucocorticoids. The patients were divided into two groups: remission group and no remission group. Multivariable logistic regression analysis was used to determine the baseline clinical-pathological influencing factors for the remission of IMN in the enrolled patients. Results The number of total remission (including complete and partial remission) of the first CTX combined with glucocorticoid treatment in 228 patients with IMN was 188(82.5%). Among them, 141 patients (61.8%) had complete remission (CR), the median time for CR was 8(6, 12) months, and the median time for partial remission (PR) was 3(1, 4) months. The median follow-up time for this study was 25(13, 43) months. Compared with the remission group, the serum albumin level was lower in the non-remission group, the 24-hour urine protein content, the blood complement C3 and C4 levels were higher, and the pathological stage was milder (all P﹤0.05). Multivariate logistic regression analysis suggested that the levels of baseline serum albumin, complement C4, and pathological stage were independent predictors of clinical remission in IMN patients. Twenty-four non-remission patients were treated with CNI. The overall response rate was 66.7%(16/24) at 6 months and 77.3%(17/22) at 12 months. Conclusions The levels of baseline albumin, blood complement C4, and pathological stage were independent predictors of clinical remission in IMN patients treated with CTX plus glucocorticoids. The non-remission patients with CTX combined with glucocorticoid therapy can still achieve a higher response rate after adjusting for CNI. 相似文献
9.
Yuanqing Yao Jun Qian Shunkang Rong Yuwen Huang Bo Xiong Gang Yang Dengqing Zhang Shimin Deng Jie Tan Que Zhu Changming Deng Dichuan Liu Haitao Ran Zhigang Wang Jing Huang 《Ultrasound in medicine & biology》2019,45(2):490-499
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases. 相似文献
10.
大学生自杀现象越发严重,如何有效的进行预防和干预大学生自杀成为全社会共同关心的话题.存在性危机是大学生自杀的一个重要原因,无意义感使其丧失了对生活的信心.不同的学科和学者分别从各自的领域出发,从自身的视角来看待和理解这一主题,并提出了相对应的策略.心理学家弗兰克尔所创立的意义疗法不但是一种心理咨询与治疗的方法,更是寻找和发现生命意义的哲学智慧.本文尝试从意义疗法的3个基本理论出发,对如何预防和干预大学生自杀提出一些对策,以期对往后的相关预防和干预大学生自杀工作提供新的视角. 相似文献