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Early and marked up-regulation of TNF-α in acute respiratory distress syndrome after cardiopulmonarybypass

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《医学前沿（英文）》 2012年第6卷第3期页码 296-301 doi: 10.1007/s11684-012-0219-1

摘要：

Despite the technique of cardiopulmonary bypass (CPB) improved the development of modern cardiac surgery, many factors during CPB have been reported to induce acute respiratory distress syndrome (ARDS). The present study was to investigate which pro-inflammatory factors involved in the early phase of ARDS. Ten patients underwent valve replacement surgery with or without ARDS were enrolled for analysis of pulmonary function and inflammatory factors release including white blood cell (WBC), neutrophils, CD11b, CD18, interleukin (IL)-8 and tumor necrosis factor-α (TNF-α). The results demonstrated that the ratio of arterial oxygen tension/fraction of inspire oxygen (PaO₂/FiO₂) was greatly reduced in ARDS patients, but only the release of TNF-α was significantly increased, which was reversely correlated to the values of PaO₂/FiO₂. Also, the count of neutrophils adhesive to pulmonary endothelial cells was significantly increased in ARDS patients. Therefore, we concluded that TNF-α was quickly up-regulated and involved in the pathogenesis of CPB-induced ARDS via guiding primed neutrophils to pulmonary interstitium.

关键词： tumor necrosis factor-α cardiopulmonary bypass inflammation acute respiratory distress syndrome

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Evaluation of a developed bypass viscous damper performance

Mahrad FAHIMINIA, Aydin SHISHEGARAN

《结构与土木工程前沿（英文）》 2020年第14卷第3期页码 773-791 doi: 10.1007/s11709-020-0627-2

摘要： In this study, the dynamic behavior of a developed bypass viscous damper is evaluated. Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston. Accordingly, the viscosity coefficient of the damper can be adjusted using geometrical dimensions of the hose. Moreover, the external orifice acts as a thermal compensator and alleviates viscous heating of the damper. According to experimental results, Computational Fluid Dynamic (CFD) model, a numerical formula and the simplified Maxwell model are found and assessed; therefore, the verification of numerical and computational models are evaluated for simulating. Also, a simplified procedure is proposed to design structures with bypass viscous dampers. The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers, and it is compared with the same structure, which is designed with concentric braces and without dampers. Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements. Moreover, seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.

关键词： developed viscous damper external orifice energy dissipation seismic behavior CFD model of viscous damper a simplified model

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Contemporary coronary artery bypass grafting

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《医学前沿（英文）》 2014年第8卷第4期页码 395-398 doi: 10.1007/s11684-014-0374-7

摘要：

Current evidence clearly demonstrates that coronary artery bypass grafting (CABG) remains the “gold standard” treatment for most patients with multivessel and left main stem disease. This article summarizes the relevant evidence basis demonstrating that CABG, in comparison to stenting, reduces mortality and subsequent myocardial infarction and the need for repeat revascularization. The article also describes the evidence basis to support the use of more arterial grafts during CABG and the current role of off-pump CABG.

关键词： coronary artery bypass grafting (CABG) coronary artery disease left main arterial grafts internal mammary artery off-pump CABG

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From gut changes to type 2 diabetes remission after gastric bypass surgeries

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《医学前沿（英文）》 2013年第7卷第2期页码 191-200 doi: 10.1007/s11684-013-0258-2

摘要：

Increasing evidence suggests that the gut may influence the host’s metabolism and ultimately change the outcomes of type 2 diabetes mellitus (T2DM). We review the evidence on the relationship between the gut and T2DM remission after gastric bypass surgery, and discuss the potential mechanisms underlying the above relationship: gut anatomical rearrangement, microbial composition changes, altered gut cells, and gut hormone modulation. However, the exact changes and their relative importance in the metabolic improvements after gastric bypass surgery remain to be further clarified. Elucidating the precise metabolic mechanisms of T2DM resolution after bypass surgery will help to reveal the molecular mechanisms of pathogenesis, and facilitate the development of novel diagnoses and preventative interventions for this common disease.

关键词： gastric bypass T2DM gut

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SinoSCORE: a logistically derived additive prediction model for post-coronary artery bypass grafting

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《医学前沿（英文）》 2013年第7卷第4期页码 477-485 doi: 10.1007/s11684-013-0284-0

摘要：

This study aims to construct a logistically derived additive score for predicting in-hospital mortality risk in Chinese patients undergoing coronary artery bypass surgery (CABG). Data from 9839 consecutive CABG patients in 43 Chinese centers were collected between 2007 and 2008 from the Chinese Coronary Artery Bypass Grafting Registry. This database was randomly divided into developmental and validation subsets (9:1). The data in the developmental dataset were used to develop the model using logistic regression. Calibration and discrimination characteristics were assessed using the validation dataset. Thresholds were defined for each model to distinguish different risk groups. After excluding 275 patients with incomplete information, the overall mortality rate of the remaining 9564 patients was 2.5%. The SinoSCORE model was constructed based on 11 variables: age, preoperative NYHA stage III or IV, chronic renal failure, extracardiac arteriopathy, chronic obstructive pulmonary disease, preoperative atrial fibrillation or flutter (within 2βweeks), left ventricular ejection fraction, other elective surgery, combined valve procedures, preoperative critical state, and BMI. In the developmental dataset, calibration using a Hosmer-Lemeshow (HL) test was at =β0.44 and discrimination based on the area under the receiver operating characteristic curve (ROC) was 0.80. In the validation dataset, the HL test was at =β0.34 and the area under the ROC (AUC) was 0.78. A logistically derived additive model for predicting in-hospital mortality among Chinese patients undergoing CABG was developed based on the most up-to-date multi-center data from China.

关键词： coronary artery bypass grafting risk stratification in-hospital mortality

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Correlation of Twist upregulation and senescence bypass during the progression and metastasis of cervical

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《医学前沿（英文）》 2014年第8卷第1期页码 106-112 doi: 10.1007/s11684-014-0307-5

摘要：

Cervical carcinoma is associated with high propensity for local invasion and lymph node metastasis. However, the molecular alterations that drive progression and metastasis of cervical cancer remain unclear. Cellular senescence has been proposed as the mechanism that protects an organism against cancer progression and metastasis. In addition, Twist, a basic helix-loop-helix transcription factor, has been suggested as an oncogene because it is overexpressed in many types of human cancer. This gene also exhibits a positive function in regulating invasion and metastasis. In this study, Twist was strongly and positively expressed in normal tissue, squamous cell carcinoma (SCC) IA--IIA, and SCC IIB--IIIB (4.3%, 44%, and 88.9%, respectively). The strong positive expressions of the senescence marker CBX3 were 39.1%, 32%, and 15.6%, respectively. The strong positive expressions of Twist in the SCC groups with or without lymph node metastasis were 80.8% and 50%. For CBX3, such expressions were 7.7% and 29.5%, respectively. Results also showed that the expression of Twist was inversely correlated with that of CBX3. Moreover, the knockdown of Twist with target siRNA in SiHa triggered the induction of the chromatin marker of the cellular senescence CBX3 and senescence-associated β-galactosidase activity. Our results suggested that the expression of Twist increased during the progression and metastasis of cervical cancer. Furthermore, Twist-induced senescence bypass is important in this process.

关键词： cervical cancer senescence Twist CBX3 lymph node metastasis

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Role of stair-climbing test in predicting postoperative cardiopulmonary complications in elderly patients

Pei-Tu REN BM, Bao-Chun LU MM, Zhi-Liang CHEN MM, Hong FU MM,

《医学前沿（英文）》 2010年第4卷第1期页码 77-81 doi: 10.1007/s11684-010-0005-x

摘要： One hundred and twenty-six patients above 80 years old with biliary diseases undergoing operations in Shaoxing People’s Hospital from Jan. 2002 to Jan. 2007 were analyzed retrospectively. All patients performed a preoperative stair-climbing test, and the risks for cardiopulmonary €complications were evaluated with pair-matching and linear correlations analysis between stair-climbing height (h) and left ventricular ejective factor (EF), forced vital capacity (FVC) and forced expiratory volume in one second (FEV). There was a significant difference in the incidence of cardiopulmonary complications among different stair-climbing heights. Stair-climbing heights were positively related with EF, FVC and FEV. This suggests that the stair-climbing test is an effective and simple method for predicting cardiopulmonary complications in elderly patients with biliary diseases.

关键词： biliary disease cardiopulmonary complication stair-climbing test

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Experimental study on the establishment and maintenance of brain death model with pigs

ZHANG Shuijun, SHI Jihua, ZHAI Wenlong, SONG Yan, CHEN Shi

《医学前沿（英文）》 2007年第1卷第2期页码 161-166 doi: 10.1007/s11684-007-0030-6

摘要： It remains controversial that after the transplantation of using grafts from brain-dead donors, organs injury and rejection can influence the effects of transplantation. This study sought to explore methods of establishing a stable brain death (BD) model using Bama mini pigs and to maintain the brain-dead state for a comparatively long period to provide a model for investigating changes in brain death. Sixteen anesthetized Bama mini pigs were randomized into a control group ( = 5) and a BD group ( = 11). Intracranial pressure (ICP) was increased in a modified, slow, and intermittent way to establish BD. Respiration and circulation were sustained during the brain-dead state. Hemodynamic changes were monitored during the experiment. In the BD group, 10 pigs met the requirements for brain death and 1 died of cardiopulmonary complications following an increase in ICP. Brain death was maintained for more than 48 hours with artificial life support. During the experiment, the heart rate and blood pressure showed characteristic changes due to increased ICP. Prior to BD being established, a tic reaction inevitably occurred. We used an improved method of increasing ICP to establish a stable BD model. The BD state could be maintained for more than 48 hours with effective respiratory and circulatory support. Disappearance of the tic reaction was considered to be one of the verified indexes for BD via encephalic pressure increase.

关键词： BD control Hemodynamic cardiopulmonary modified

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环境同位素示踪方法研究新安江右坝肩绕坝渗流

陈建生,刘建刚,董海洲,陈亮

《中国工程科学》 2004年第6卷第1期页码 57-63

摘要：

通过分析新安江右坝区环境水中的同位素²H，¹⁸O，³H以及温度与电导分布，研究新安江右坝存在的绕坝渗流场。环境同位素数据证实了右坝肩基岩中存在着绕坝渗漏，排水廊道中的排水既有边坡降雨入渗，又有库水的绕坝肩补给，排水廊道扇形孔中的渗水完全来自于绕坝肩的库水渗漏。3E_1-1扬压力升高的原因是由于F0断层渗漏造成的结果，但6坝段和7坝段下部的F1断层基本上不存在渗漏,灌浆廊道G7-4排水孔中渗水中的³H高达19.54TU，证实该渗漏水来自坝后区的降雨补给。右坝肩观测孔R3和R6等孔中发现绕坝库水成分，环境同位素数据同时证实了人工示踪方法得到的结论。

关键词：环境同位素绕坝渗流大气降水水库