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11.
Objective: Association of matrix metalloproteinases (MMPs) gene polymorphisms with rheumatoid arthritis is controversial. We conduct a meta-analysis to clarify this dispute.

Methods: We systematically searched the electronic PUBMED, EMBASE and CNKI databases for research articles about MMPs (MMP-1, MMP-2, MMP-3, MMP-9) gene polymorphisms and rheumatoid arthritis (RA) up to January 2015. According to the heterogeneity, fixed-effects or random-effects models were used to calculate crude odds ratios (ORs) and 95% confidence intervals (95% CIs).

Results: A total of 11 articles involving 2143 cases and 2049 controls were included in this meta-analysis. Overall, no significant associations were observed between MMP-1-1607 1G/2G polymorphism and RA. Stratification by ethnicity, no significant associations were observed in Caucasian populations. Similarly, no significant associations were observed between MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms and RA in overall and Caucasian populations, respectively. However, a weak association was found between MMP-2-1306 C/T polymorphism and RA (C vs. T, OR?=?0.813, 95%CI?=?0.694–0.953, p?=?0.010) in overall populations.

Conclusions: The present meta-analysis suggests that MMP-1-1607 1G/2G, MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms are not associated with the susceptibility of RA, but MMP-2 -1306 C/T is weakly associated with susceptibility to RA. Further studies with more sample size are needed for definitive conclusions.  相似文献   
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简要介绍了GE宝石能谱CT(Discovery CT750 HD)的技术特点,详细阐述了日常使用中出现的间歇性停机、无法进行Fastcal(快速空气校正)以及扫描中断和gantry(扫描架)自动复位3例故障的维修过程,为医院维修人员维修类似故障提供了参考。最后总结了医疗设备常见故障及主要故障原因,提出了快速排查CT故障的方法,并建议在日常使用中及时保养维护以降低设备故障率。  相似文献   
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Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.  相似文献   
15.
Epidemiological studies on magnesium intake and primary liver cancer (PLC) are scarce, and no prospective studies have examined the associations of magnesium intake with PLC incidence and mortality. We sought to clarify whether higher magnesium intake from diet and supplements was associated with lower risks of PLC incidence and mortality in the US population. Magnesium intake from diet and supplements was evaluated through a food frequency questionnaire in a cohort of 104,025 participants. Cox regression was employed to calculate hazard ratios for PLC incidence and competing risk regression was employed to calculate subdistribution hazard ratios for PLC mortality. Restricted cubic spline regression was employed to test nonlinearity. We documented 116 PLC cases during 1,193,513.5 person-years of follow-up and 100 PLC deaths during 1,198,021.3 person-years of follow-up. Total (diet + supplements) magnesium intake was found to be inversely associated with risks of PLC incidence (hazard ratiotertile 3 vs. 1: 0.44; 95% confidence interval: 0.24, 0.80; ptrend = 0.0065) and mortality (subdistribution hazard ratiotertile 3 vs. 1: 0.37; 95% confidence interval: 0.19, 0.71; ptrend = 0.0008). Similar results were obtained for dietary magnesium intake. Nonlinear inverse dose–response associations with PLC incidence and mortality were observed for both total and dietary magnesium intakes (all pnonlinearity < 0.05). In summary, in the US population, a high magnesium intake is associated with decreased risks of PLC incidence and mortality in a nonlinear dose–response manner. These findings support that increasing the consumption of foods rich in magnesium may be beneficial in reducing PLC incidence and mortality.  相似文献   
16.
赵胜楠  侯鹏 《中国药事》2020,34(7):759-765
异常毒性最初是一种确保复杂成分制剂生产工艺一致性及安全性的辅助检测手段,后来成为针对外源性毒性污染物的通用安全性检测项,曾在世界范围内被各国药典收载。由于该检测与药品质量、安全性之间的关联性受到质疑,各国药典逐渐在各论及通则中删除该检测项,目前仅《中国药典》保留异常毒性。由于该检测存在设定限值难以统一、给药体积及给药剂量不合理、结果易受干扰且缺乏明确的判定标准等试验原理及设计上的缺陷,导致其试验结果没有实际参考意义。基于对历史数据的回顾分析,国际监管机构及卫生组织对异常毒性有了更为科学的认知,并已逐渐形成统一的监管共识:严格的生产控制措施和有效的质量检测手段,比异常毒性检测更为重要;异常毒性检测结果或与产品质量及污染不具相关性;在异常毒性检查中使用大量动物不符合动物福利和“3R”原则。本文从科学角度试论异常毒性作为药品质量控制指标的合理性,并总结异常毒性修订的科学原则,希望能为我国监管机构、制药行业修订异常毒性相关内容提供思考角度。  相似文献   
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Based on the physical randomization of completely randomized experiments, in a recent article in Statistics in Medicine, Rigdon and Hudgens propose two approaches to obtaining exact confidence intervals for the average causal effect on a binary outcome. They construct the first confidence interval by combining, with the Bonferroni adjustment, the prediction sets for treatment effects among treatment and control groups, and the second one by inverting a series of randomization tests. With sample size n, their second approach requires performing O(n4)randomization tests. We demonstrate that the physical randomization also justifies other ways to constructing exact confidence intervals that are more computationally efficient. By exploiting recent advances in hypergeometric confidence intervals and the stochastic order information of randomization tests, we propose approaches that either do not need to invoke Monte Carlo or require performing at most O(n2)randomization tests. We provide technical details and R code in the Supporting Information . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
19.
矿物药是传统中医药的重要组成部分,具有悠久的应用历史。其中矿物止血药对多种出血病证的临床应用广泛、用药经验丰富且疗效显著。石膏作为临床常用的矿物药,生石膏的功效为清热泻火、除烦止渴,而煅石膏为生石膏经高温煅烧的炮制品,主要由无水硫酸钙(CaSO4)组成,具有收湿、生肌、敛疮、止血的功效,常外用于治疗溃疡不敛、湿疹瘙痒、水火烫伤、外伤出血等。止血机制研究表明,Ca2+作为凝血因子Ⅳ参与凝血过程的内外凝血级联多个关键环节,并且参与调节血小板活化、聚集,促进生成不溶性纤维蛋白,最终形成血凝块防止出血。Ca2+是重要的止血物质基础,但是石膏、煅石膏均含有Ca2+,煅石膏具有显著的止血作用,而石膏没有止血作用,石膏经过炮制后性味、功效发生了明显改变,体现了炮制特色,但目前尚未完全阐明煅石膏的炮制机制。因此,该文对石膏煅制前后比较研究情况进行总结与分析,围绕煅制工艺、晶型比较、元素含量、药效比较等进行综述,并总结Ca2+参与止血的各个环节。此外,对其他含钙矿物药及新型含钙止血材料如海藻酸钙、介孔硅酸钙和纳米凝胶止血材料的止血性能进行探讨,以期为阐明煅石膏的炮制机制提供借鉴,为临床辨证使用煅石膏提供依据,并为后续新型含钙止血材料的开发提供借鉴。  相似文献   
20.
目的 探讨构建的可切除肺癌预后预测模型在患者生存及预后预测中的价值。方法 选择山西省肿瘤医院2007年1月至2018年9月原发性肺癌患者2 267例,患者均行一次肺癌手术治疗,无第二原发肿瘤。选取性别、年龄、职业、肿瘤部位、病理类型、手术路径、手术方式、肿瘤分期、治疗方案为预后影响因素。采用Cox比例风险模型构建预后指数(PI)方程,计算每例患者的PI值。根据PI值的不同范围,划分低、中、高危预后组,对各组生存情况进行评估。结果 性别(RR=0.684,P=0.001)、年龄(RR=0.591,P<0.01)、职业(RR=1.439,P=0.001)、病理类型(RR=3.694,P<0.01)、手术路径(RR=0.734,P=0.001)、肿瘤分期(RR=0.352,P=0.007)为可切除肺癌患者预后独立影响因素。其中,女性、≤65岁、胸腔镜手术、肿瘤分期Ⅰ期为预后保护因素,其预后不良风险分别降低31.6%、40.9%、26.6%、64.8%;农民、腺鳞癌为预后危险因素,其预后不良风险分别增加43.9%、269.4%。PI方程为:∑βixi=-0.380 X1-0.526 X2+0.364 X31+1.307 X55-0.309 X6-1.045 X81(X1代表性别,X2代表年龄,X31代表职业为农民,X55代表病理类型为腺鳞癌,X6代表手术路径,X81代表肿瘤分期Ⅰ期)。PI<-1为低危组,PI≥-1且≤-0.5为中危组,PI>-0.5为高危组。1、3、5年生存率低危组分别为96.8%、87.0%、77.9%,中危组分别为91.8%、82.2%、61.7%,高危组分别为86.5%、61.7%、50.3%,各组间生存率差异具有统计学意义(P<0.05)。结论 可切除肺癌预后预测模型能够预测可切除肺癌患者的预后风险及相应生存率,帮助临床医师评估预后及制订后续治疗方案。  相似文献   
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