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31.
This study investigated the hypocholesterolaemic effects of bitter melon aqueous extracts (BMAE) in vitro, the inhibitory effects of BMAE on pancreatic cholesterol esterase (CEase) and incorporation of cholesterol into micelles were investigated. BMAE decreased the in vitro micellar solubility of cholesterol in a dose-dependent manner. The conformation of CEase was investigated by means of circular dichroism (CD) and fluorescence. The result revealed the decrease of α-helix contents, increase of β-sheet and exposure of aromatic amino acid residuals. The incorporation of cholesterol into micelles was inhibited by BMAE. A complex was observed by transmission electron microscopy (TEM), which indicated interaction between cholesterol and BMAE. The result revealed that BMAE can play a role in decreased intestinal cholesterol absorption via inhibition of CEase, and of micelle formation.  相似文献   
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目的观察膀胱肿瘤切除术后患者尿路感染发生情况与病原学特征,分析诱发尿路感染的危险因素,并提出合理且具备针对性的冲洗对策,为未来膀胱肿瘤切除术后尿路感染的预防提供合理参考。方法回顾性分析连云港市第一人民医院2016年1月-2019年1月接受经尿道膀胱肿瘤切除术治疗的451例膀胱肿瘤患者的临床资料,收集患者病例资料,全部患者术后均定期取尿液标本进行细菌培养,参照相关标准判定患者尿路感染情况,记录患者一般情况,包括一般人口学资料(性别、年龄、体质量、受教育程度等),同时记录患者糖尿病的疾病合并情况,将术后尿路感染可能的危险因素纳入初步分析,Logistic多因素回归分析膀胱肿瘤切除术后发生尿路感染的危险因素。结果451例膀胱肿瘤切除术患者术后第3天尿液中细菌培养阳性例数为80例,阳性率为17.74%,在使用抗菌药物后,患者尿液中细菌培养阳性率逐渐降低,各时点尿液细菌阳性培养率比较,差异有统计学意义(P<0.05);经多因素Logistic回归分析检验证实,高龄、血糖水平控制不佳、术前留置导尿管、多发肿瘤是膀胱肿瘤切除术后尿路感染的危险因素(OR>1,P<0.05);80例术后尿液细菌培养阳性患者共分离出87株菌株,其中革兰阴性菌66株占75.86%,革兰阳性球菌21株占24.14%。结论膀胱肿瘤切除术后患者有较高的尿路感染风险,革兰阴性菌是主要的感染病原菌,年龄、基础疾病、肿瘤位点、术前导尿管留置等是影响因素,这类患者应引起临床高度重视。  相似文献   
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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   
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