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71.
ObjectiveThe Recruitment Innovation Center (RIC), partnering with the Trial Innovation Network and institutions in the National Institutes of Health-sponsored Clinical and Translational Science Awards (CTSA) Program, aimed to develop a service line to retrieve study population estimates from electronic health record (EHR) systems for use in selecting enrollment sites for multicenter clinical trials. Our goal was to create and field-test a low burden, low tech, and high-yield method.Materials and MethodsIn building this service line, the RIC strove to complement, rather than replace, CTSA hubs’ existing cohort assessment tools. For each new EHR cohort request, we work with the investigator to develop a computable phenotype algorithm that targets the desired population. CTSA hubs run the phenotype query and return results using a standardized survey. We provide a comprehensive report to the investigator to assist in study site selection.ResultsFrom 2017 to 2020, the RIC developed and socialized 36 phenotype-dependent cohort requests on behalf of investigators. The average response rate to these requests was 73%.DiscussionAchieving enrollment goals in a multicenter clinical trial requires that researchers identify study sites that will provide sufficient enrollment. The fast and flexible method the RIC has developed, with CTSA feedback, allows hubs to query their EHR using a generalizable, vetted phenotype algorithm to produce reliable counts of potentially eligible study participants.ConclusionThe RIC’s EHR cohort assessment process for evaluating sites for multicenter trials has been shown to be efficient and helpful. The model may be replicated for use by other programs.  相似文献   
72.
不同糖耐量个体胰岛β细胞功能观察及评价   总被引:1,自引:0,他引:1  
Liu J  Li YB  Shao H  Li YX  Yuan YH  Xiao YB  Weng JP 《中华医学杂志》2007,87(18):1252-1255
目的评价正常糖耐量(NGT)、糖调节受损(IGR)、新诊断2型糖尿病(T2DM)个体胰岛β细胞功能及其相关指标的适用性。方法178例入选者行口服和静脉葡萄糖耐量试验。检测胰岛素生成指数(ΔI30/ΔG30)、胰岛素急性分泌时相(AIR)、β细胞功能指数(HOMA β)、空腹胰岛素原(FPI)及胰岛素原/胰岛素(PI/I)比值反映胰岛素分泌功能。结果IGR组的ΔI30/ΔG30、AIR较NGT组分别下降了38%、39%,HOMA β轻度下降(19%);T2DM组的胰岛β细胞功能降低更明显,其中AIR下降84%,ΔI30/ΔG30下降70%、HOMA β下降62%。T2DM组FPI和PI/I比值也比NGT组明显升高(24.4pmol/L±18.0pmol/L or 10.9pmol/L±6.7pmol/L;14.7%±10.5%or10.0%±6.5%,P〈0.05)。ΔI30/ΔG30和AIR相关性好(r=0.75,P〈0.001)。结论IGR患者主要表现胰岛素分泌时相缺陷和HOMA β降低,至糖尿病阶段则伴有胰岛素分泌质量下降。ΔI30/ΔG30和AIR均可准确反映IGR患者胰岛β细胞功能,而在新诊断2型糖尿病患者中AIR更适用,若应用ΔI30/ΔG30须校正胰岛素抵抗。  相似文献   
73.
激光生物效应及医学应用研究   总被引:1,自引:0,他引:1  
李海涛  杨继庆 《医学争鸣》2007,28(14):1341-1342
激光作用于生物体会产生物理、化学或生物学的效应,激光正是通过这些效应达到医学基础研究、诊断和治疗疾病的目的.本文简介了激光与生物组织相互作用所产生的生物效应,概述了激光生物效应在生物学和医学研究中的应用.  相似文献   
74.
Summary The reversing effect of wild-type PTEN gene on resistance of C13K cells to cisplatin and its inhibitory effect on the phosphorylation of protein kinase B (AKT) were studied. The expression of PTEN mRNA and protein in OV2008 cells and C13K cells were semi-quantitatively detected by using RT-PCR and Western blotting. Recombinant eukaryotic expression plasmid containing human wild-type PTEN gene was transfected into C13K cells by lipofectamine2000. The expression of PTEN mRNA was monitored by RT-PCR and the expression of PTEN, Akt, p-Akt protein were analyzed by Western blotting in PTEN-transfected and non-transfected C13K cells. Proliferation and chemosensitivity of cells to DDP were measured by MTT, and cell apoptosis was detected by flow cytometry after treatment with cisplatin. The expression of PTEN mRNA and protein in OV2008 cells were significantly higher than those in C13K cells. After transfection with PTEN gene for 48 h, the expression of PTEN mRNA and protein in C13K cells were 2.04 ± 0.10, 0.94 ± 0.04 respectively and the expression of p-Akt protein (0.94 ± 0.07) was lower than those in control groups (1.68 ± 0.14, 1.66 ± 0.10) (P < 0.05). The IC50 of DDP to C13K cells transfected with PTEN (7.2 ± 0.3 μmol/L) was obviously lower than those of empty-vector transfected cells and non-transfected cells (12.7 ± 0.4 μmol/l, 13.0 ± 0.3 μmol/L) (P<0.05). The apopototis ratio of wild-type PTEN-transfected, empty vector transfected and non-transfected C13K cells were (41.65 ± 0.87)%, (18.61 ± 0.70)% and (15.28 ± 0.80)% respectively, and the difference was statistically significant (P<0.05). PTEN gene plays an important role in ovarian cancer multidrug resistance. Transfection of PTEN could increase the expression of PTEN and restore drug sensitivity to cisplatin in human ovarian cancer cell line C13K with multidrug-resistance by decreasing the expression of p-Akt. This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30571950) and National Key Basic Research Program Foundation (NO.2002CB513107).  相似文献   
75.

Background

Carbon monoxide (CO) poisoning has recently become a serious health problem in some Asian countries, including Taiwan. The aims of this study are to evaluate the changing trend of CO poisoning and to demonstrate the association between myocardial injury and neurological sequelae of CO poisoning in Taiwan between 1990 and 2011.

Methods

This retrospective cohort study included all eligible patients with acute CO poisoning reported to the Taiwan National Poison Control Center during the study period. The changing trend of CO poisoning and its impacts on the primary outcomes, i.e., persistent neurological sequelae (PNS) and delayed neurological sequelae (DNS), were then assessed.

Results

786 CO poisoned cases were reported. Among them, 467 cases were intentional. Intentional CO exposure started to become the major cause of CO poisoning in Taiwan in 2002. Increase in the number of intentional CO poisoning significantly correlated with the increase in the overall number of CO poisoning (r = 0.972, p < 0.001). Patients who took tranquilizer (OR = 3.89; 95% CI:1.94–7.77), had myocardial injury (OR = 1.70; 95% CI:1.03–2.82), had been stayed in intensive care unit (OR = 2.03; 95% CI:1.13–3.62), presented with GCS less than 9 (OR = 4.05; 95% CI:2.32–7.08) and had abnormal brain image (OR = 14.46; 95% CI:5.83–35.83) had a higher risk of PNS. Moreover, patients who were older age (OR = 1.04; 95% CI:1.02–1.07), had psychiatric disorder history (OR = 2.82; 95% CI:1.35–5.89), had myocardial injury (OR = 1.33; 95% CI:1.16–1.53), and presented with GCS less than 9 (OR = 3.23; 95% CI:1.65–6.34) had a higher risk of DNS.

Conclusion

The pattern of CO poisoning had changed markedly during the study period, with a significant increase in both the numbers of intentional and overall CO poisoning. Moreover, intentional CO poisoning was associated with a higher risk of neurological sequelae, which was mediated by various indicators of poisoning severity such as myocardial injury and GCS less than 9.  相似文献   
76.
77.
目的探讨全息影像术中导航在泌尿外科腹腔镜和机器人手术中的应用价值。方法回顾性分析2019年1—12月北京和睦家医院等19家医疗中心收治的86例患者的病例资料,临床诊断包括肾肿瘤78例,膀胱癌2例,肾上腺肿瘤2例,肾囊肿1例,前列腺癌1例,汗腺癌淋巴结转移1例,根治性膀胱切除术后盆腔转移瘤1例。其中,32例接受标准腹腔镜手术,分别为肾部分切除术(LPN)27例,根治性前列腺切除术1例,根治性膀胱切除术2例,肾上腺肿瘤切除术2例;54例接受达芬奇机器人手术,分别为肾部分切除术(RAPN)51例,腹膜后淋巴结清扫术1例,双侧肾囊肿去顶减压术1例,盆腔转移肿瘤切除术1例。两种术式的肾部分切除术患者中41例有可统计的临床数据,其中RAPN 23例,LPN 18例。男26例,女15例;中位年龄53.5(24~76)岁;中位R.E.N.A.L评分7.8(4~11)分。专业工程师根据86例术前增强CT检查图像和诊断报告重建全息影像。术前,全息影像可帮助术者对供应肿瘤或手术切除部位的动静脉血管、淋巴结和神经的立体空间结构及相互关系有更直观的认识,协助术前手术规划。在术中将全息影像与腹腔镜监视器中的术野图像进行实时追踪和融合,实现术中导航。结果本组86例手术均顺利完成。术中通过人工调整全息影像,可提示重要血管如肾动脉和肾静脉在体内的投影位置,帮助术者定位血管、淋巴结和其他重要解剖结构的位置,便于精准分离。本研究采用标准腹腔镜手术和达芬奇机器人手术的肾部分切除术患者中共41例有可统计的临床数据。41例中位手术时间140(50~225)min,其中RAPN为140(50~215)min,LPN为160(80~225)min;中位热缺血时间23(14~60)min,其中RAPN为21(17~40)min,LPN为25(14~60)min;中位出血量80(5~1200)ml,其中RAPN为150(30~1200)ml,LPN为50(5~1200)ml。术中无周围重要脏器损伤。2例LPN患者出现ClavienⅡ级并发症,1例出血1200 ml给予输血,另一例血肿未予处理,自行吸收。此2例分别为前、后肾门肿瘤,R.E.N.A.L评分均为11分。结论全息影像术中导航可协助术者在腹腔镜和机器人手术中对重要的解剖结构进行定位、识别,在减少术中组织和器官损伤、降低手术并发症和提高手术成功率方面有重要的应用价值。  相似文献   
78.
从减速机、联轴器、扇叶与风筒的检查维护以及润滑油系统、振动和腐蚀的监测等六个方面,介绍了冷却塔风机维护与检修的方法,同时介绍了对冷却塔的播水系统的改进。  相似文献   
79.
主要叙述了电缆做预防性试验及其试验项目、方法和要求,以及需注意的问题。  相似文献   
80.
目的 了解前列腺癌组织标本中跨膜丝氨酸蛋白酶2(TMPRSS2)基因与ETS转录因子家族成员ETS相关基因(ERG)、ETS变异体1(ETV1)及ETS变异体4(ETV4)基因之间的融合情况及意义.方法 采用巢式逆转录聚合酶链反应(RT-PCR)琼脂糖凝胶电泳法检测32例前列腺癌患者及34例前列腺良性增生患者前列腺组织中TMPRSS2基因与ETS家族基因融合的TMPRSS2/ERG、TMPRSS2/ETV1、TMPRSS2/ETV4转录体;琼脂糖凝胶电泳阳性者,纯化PCR产物进行直接测序,用BLAST在线软件比对确定融合位点;分析融合基因与Gleason分级关系.结果 在32例前列腺癌患者组织标本中,检测到TMPRSS2/ERG融合基因17例(53.1%),含5种不同融合基因亚型,其中1种为新发现融合基因亚型(GenBank登录号:EU090248),单一标本中可检测到1种以上TMPRSS2/ERG融合基因亚型;检测到TMPRSS2/ETV1融合基因2例(6.3%),为新发现融合基因亚型(GenBank 登录号:EU090249);未检到TMPRSS2/ETV4融合基因型.34例前列腺良性增生组织标本中均未检测到TMPRSS2/ERG、TMPRSS2/ETV1和TMPRSS2/ETV4融合基因型.按Gleason评分值分为中分化与低分化的两组前列腺癌组织标本之间融合基因阳性率差异无统计学意义(P=0.169).结论 前列腺癌组织中存在TMPRSS2/ERG和TMPRSS2/ETV1融合基因及多种亚型;前列腺癌融合基因的发现有望为前列腺癌的发病机制研究提供新的思路.  相似文献   
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