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Chinese Science Bulletin 2009年第9期54卷 1543-1554页

作者： LIU Rui ZHOU Han Wen ZHANG Li ZHONG ZengQiu ZENG Wen XIANG Hua JIN Song LU xin qian LI ChunZhong State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences (Wuhan) Wuhan 430074 China State Key Laboratory of Continental Dynamics Northwest University Xi'an 710069 China The 7th Geological Team of Zhejiang Province Lishui 323000 China

A combined study of zircon LA-ICP-MS U-Pb dating, trace elements and Hf isotope was carried out for gneissic granite from the Sanzhishu area in Jingning, SW Zhejiang Province. Nearly all the zircons separated from the granite exhibited oscillatory zoning and high Th/U ratios (>0.1). The REE profile showed a pronounced positive Ce anomaly, negative Eu anomaly and an enrichment of HREE, which are typical characteristics of magmatic zircon. Thirteen concordant or nearly concordant analytical data yielded a weighted mean 207Pb/206Pb age of 1860±13 Ma (MSWD=0.084), representing the formation age of the granite. The magmatic zircons had negative εHf(t) values of -15.6 to -10.0 and two-stage Hf model ages of 3.1 to 3.4 Ga, indicating that the granites were formed by reworking of ancient crust. The major- and trace-element data indicate that the gneissic granites are metaluminous high-K calc-alkaline rocks and exhibit the same geochemical characteristics as aluminous A-type granites, implying the emplacement of the granite in a post-orogenic extensional tectonic setting. We conclude that the Pa-leoproterozoic crustal reworking event in the Cathaysia Block of South China marked the transition from assembly to break-up of the Columbia supercontinent.

关键词：微量元素铪同位素古元古代锆石改造地壳中国 Pb

阻隔包装专用乙烯-乙烯醇共聚物的结构与性能

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合成树脂及塑料 2018年第2期35卷 58-62,73页

作者：钱鑫北京燕山石化高科技术有限责任公司北京市102500

分析了乙烯-乙烯醇共聚物(EVOH)的结构与性能及其序列结构,并研究了EVOH的力学性能、熔融结晶性能、热性能和吸水性能。通过多层共挤流延工艺制备了五层复合薄膜,考察EVOH的加工性能,以及乙烯含量对EVOH阻隔性能的影响。结果表明:EVOH... 详细信息

分析了乙烯-乙烯醇共聚物(EVOH)的结构与性能及其序列结构,并研究了EVOH的力学性能、熔融结晶性能、热性能和吸水性能。通过多层共挤流延工艺制备了五层复合薄膜,考察EVOH的加工性能,以及乙烯含量对EVOH阻隔性能的影响。结果表明:EVOH具有适宜的熔体流动速率、良好的热稳定性能和力学性能,乙烯摩尔分数28%~38%,密度1.164~1.203 g/cm^3,醇解度100%;经过多层共挤加工,所制薄膜具有很好的阻隔效果,可满足下游用户对阻隔高分子材料用于包装、注塑等领域的性能需求。

关键词：乙烯-乙烯醇共聚物阻隔性加工性能序列结构

A Study of Quasi-Monochromatic X-Ray Sources for Breast Cancer Early Detection

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2018年第2期7卷 184-192页

作者： xin qian Lindsay Puckett Zhijun Cai Department of Radiation Medicine Northwell Health Great Neck NY USA Department of Radiology University of Iowa Hospitals and Clinics Iowa City IA USA

Objectives: Early detection and treatment provide the opportunity to decrease the mortality rate from breast cancer. Quasi-monochromatic technique can enhance low contrast lesion detection by eliminating beam-hardening artifacts. We hypothesized that this technique would be feasible and can be used to assist in breast cancer early detection. Methods: The performance of stationary Digital Breast Tomosynthesis with quasi-monochromatic X-ray sources was evaluated using both simulated and physical phantoms. Normalized spectra in the fraction of total photons vs. photon energy were generated. Results: As expected, the peaked energies from sources, from smallest to largest, are Mo/Mo, W/Ag-1000, and W/Ce-10, W/Ce-100. For contrast vs. noise standard deviation on the simulated CIRS phantom, W/Ce-100 and W/Ce-10 have similar performance on both low and high contrast objects. For low contrast object, W/Ce-100 is barely noticeably better than W/Ce-10, and they are better than both W/Ag-1000 and Mo/Mo. For high contrast objects W/Ce-10 is slightly better than W/Ce-100. The spectra of the implemented W/Ce-10 X-ray source were measured, which matched the simulation well. The contrast noise ratios of reconstructed objects in American College of Radiology mammographic phantom with and without using W/Ce-10 combination are 7.1 and 5.4, respectively. Conclusions: The combination of stationary digital breast tomosynthesis and quasi-monochromatic technique can compensate the loss of X-ray flux due to heavy K-edge filtering. This technique can enable the stationary DBT scanners to operate at acceptable scanning times with better low contrast lesion detectability. Advances in Knowledge: The stationary digital breast tomosynthesis can provide high quality images within short scanning time by using X-ray source array, which makes quasi-monochromatic technique feasible.

关键词： Breast Cancer Quasi-Monochromatic Early Detection Digital Breast Tomosynthesis

Simulation platform of navigation system for autonomous underwater vehicle

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Journal of Marine Science and Application 2006年第4期5卷 33-37页

作者： QIN Zheng BIAN xin-qian College of Automation Harbin Engineering University Harbin 150001 China

In view of the characteristics of underwater navigation, the simulation platform of navigation system for autonomous underwater vehicle has been developed based on Windows platform. The system architecture, net communication and the information flow are discussed. The methods of software realization and some key techniques of the Vehicle Computer and the Navigation Equipment Computer are introduced in particular. The software design of Terrain Matching Computer is introduced also. The simulation platform is verified and analyzed through simulation. The results show that the architecture of the platform is reasonable and reliable, and the mathematic models and simulation algorithms of sub-systems are also valid and practicable.

关键词： autonomous underwater vehicle simulation platform inertial navigation terrain-aided navigation

Relationship between XRCC1 polymorphisms and susceptibility to prostate cancer in men from Han, Southern China

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Asian Journal of Andrology 2007年第3期9卷 331-338页

作者： Zheng Xu Li-xin Hua Li-xin qian Jie Yang xin-Ru Wang Wei Zhang Hong-Fei Wu Department of Urology First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China School of Public Health Nanjing Medical University Nanjing 210029 China

Aim： To investigate the association among XRCC1 polymorphisms, smoking, drinking and the risk of prostate cancer （PCa） in men from Han, Southern China. Methods： In a case-control study of 207 patients with PCa and 235 cancerfree controls, frequency-matched by age, we genotyped three XRCC1 polymorphisms （codons 194, 280 and 399） using the polymerase chain reaction-restriction fragment length polymorphism （PCR-RELP） method. Results： Among the three polymorphisms, we found that the XRCC1 Arg399Gln variant allele was associated with increased PCa risk （adjusted odd ratio [OR]： 1.67, 95% confident interval [CI]： 1.11-2.51）, but the XRCC1 Arg 194Trp variant allele had a 38% reduction in risk of PCa （adjusted OR： 0.62, 95% CI： 0.41-0.93）. However, there was no significant risk of PCa associated with Arg280His polymorphism. When we evaluated the three polymorphisms together, we found that the individuals with 194Arg/Arg wild-type genotype, Arg280His and Arg399Gln variant genotypes had a significantly higher risk of PCa （adjusted OR： 4.31; 95% CI： 1.24-14.99） than those with three wild-type genotypes. In addition, we found that Arg399Gln variant genotypes had a significant risk of PCa among heavy smokers （adjusted OR： 2.04; 95% CI： 1.03-4.05）. Conclusion： These results suggest that polymorphisms of XRCC1 appear to influence the risk of PCa and may modify risks attributable to environmental exposure.

关键词： XRCC1 polymorphism prostate cancer genetic susceptibility molecular epidemiology

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基于三维速度势场的AUV局部避碰研究

机器人 2007年第1期29卷 88-91页

作者：洪晔边信黔哈尔滨工程大学自动化学院黑龙江哈尔滨150001

以势场方法的思想为出发点,提出一种基于速度势场的AUV局部避碰仿真方法.根据AUV的特点建立了空间碰撞危险区域和由水平面速度势场和垂直面速度势场组成的三维速度势场.该方法较好地利用了相对速度的信息.仿真实验证明此方法可以使AUV... 详细信息

以势场方法的思想为出发点,提出一种基于速度势场的AUV局部避碰仿真方法.根据AUV的特点建立了空间碰撞危险区域和由水平面速度势场和垂直面速度势场组成的三维速度势场.该方法较好地利用了相对速度的信息.仿真实验证明此方法可以使AUV在水下多运动障碍物的环境中得到较好的局部避碰效果,为今后的海试打下了很好的基础.

关键词：自治式水下机器人局部避碰速度势场运动障碍物

Effect of uninterrupted dabigatran or rivaroxaban on achieving ideal activated clotting time to heparin response during catheter ablation in patients with atrial fibrillation

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Journal of Geriatric Cardiology 2022年第8期19卷 565-574页

作者： qian xin Chuang ZHANG Yu-Jia WANG Jian LI Tao CHEN Shi-xing LI Wei WANG Yu YANG Wen-Juan SONG Jin ZHOU Xiang-Min SHI Department of Cardiology the Sixth Medical CentreChinese PLA General HospitalBeijingChina Department of Health Service the Eighth Medical CentreChinese PLA General HospitalBeijingChina

BACKGROUND Uninterrupted use of oral anticoagulants before atrial fibrillation(AF)ablation can reduce the incidence of perioperative thromboembolic ***,the effect of new oral anticoagulants on activated clotting time(ACT)in respo-nse to heparin during AF ablation in Chinese populations remains *** aim of the present retrospective study was to investigate the value of ACTs in response to intraoperative heparin administration in patients using dabigatran or *** From January 2018 to December 2021,a total of 173 patients undergoing AF ablation were included in the study,in which 101 patients were treated with dabigatran,72 patients were treated with *** intraoperative ACT values were examined in both *** incidence of periprocedural complications was *** Initial heparin dosage(88±19 U/kg vs.78±27 U/kg,P<0.05),total heparin dosage(137±41 U/kg vs.106±52 U/kg,P<0.05)during the ablation procedure were higher in the dabigatran group than those in the rivaroxaban *** ACT(280±36 s vs.265±30 s,P<0.05),and the percentage of ACTs within the therapeutic range(250-350 s)(74%±26%vs.60%±29%,P<0.05)were significantly lower in the dabigatran group than those in the rivaroxaban group,particularly in male ***,the average time of achieving the target ACT(250-350 s)was also found longer in the dabigatran group(P<0.05)as compared with the rivaroxaban *** significant difference was found in the incidence of periprocedural complica-tions between the two *** The anticoagulant effect of uninterrupted rivaroxaban therapy appears to be more stable and efficient than dabigatran administration during catheter ablation in patients with AF.

关键词： patients heparin dosage

Retroperitoneal tumor finally diagnosed as a bronchogenic cyst:A case report and review of literature

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World Journal of Clinical Cases 2022年第19期10卷 6679-6687页

作者： Yang-Yang Gong xin qian Bo Liang Ming-Dong Jiang Jun Liu xing Tao Jing Luo Hong-Jian Liu You-Gang Feng Faculty of Medicine Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Urology Suining Central HospitalSuining 629000Sichuan ProvinceChina

BACKGROUND Retroperitoneal bronchogenic cyst(RBC)is an extremely rare developmental *** are benign tumors but malignant transformation is *** of their anatomical position,RBCs are easily misdiagnosed as adrenal or pancreatic solid tumors on radiological ***,we report a case of RBC,review the literature,and summarize some important *** SUMMARY A 49-year-old woman was incidentally found to have a retroperitoneal tumor during a physical *** computed tomography and laboratory evaluations,including routine blood examination,blood biochemistry,24-h urine 17 ketones,17 hydroxyls,adrenocortical hormone,serum potassium concentration,serum amylase,lipase,and epithelial tumor markers,revealed a moderate density,54 mm×40 mm mass with a clear boundary near the left adrenal *** were no abnormalities in the blood and urine *** the patient had a history of hypertension and the location of the mass was adjacent to the adrenal gland,it was initially diagnosed as a left adrenal tumor and was resected by retroperitoneal ***,the pathological examination after surgery confirmed it to be a bronchogenic *** Retroperitoneal laparoscopic surgery can be prioritized for symptomatic RBC *** treatment is feasible for selected patients.

关键词： Adrenal gland neoplasm Bronchogenic cyst Retroperitoneal Subdiaphragmatic Pancreatic cyst Case report

丝裂霉素C联合顺行泪道引流管置入治疗上泪道阻塞

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国际眼科杂志 2018年第12期18卷 2275-2277页

作者：钱欣中国江苏省无锡市第三人民医院眼科 214041

目的:探讨在顺行泪道引流管置入治疗上泪道阻塞中应用丝裂霉素C的效果。方法:选取上泪道阻塞患者78例82眼,随机分为观察组(39例42眼)与对照组(39例40眼),对照组予以顺行泪道引流管置入治疗,观察组在对照组治疗基础上联合丝裂霉素C治疗,... 详细信息

目的:探讨在顺行泪道引流管置入治疗上泪道阻塞中应用丝裂霉素C的效果。方法:选取上泪道阻塞患者78例82眼,随机分为观察组(39例42眼)与对照组(39例40眼),对照组予以顺行泪道引流管置入治疗,观察组在对照组治疗基础上联合丝裂霉素C治疗,对比两组治疗效果。结果:观察组治疗总有效率81%,显著高于对照组的62%,两组比较差异具有统计学意义(P<0. 05)。观察组治疗后的眼表改变评分26. 25±1. 67分、眼泪SP(P物质)含量256. 32±10. 07pg/mL低于对照组,泪膜破裂时间8. 85±0. 89s短于对照组的9. 58±0. 92s,两组比较差异均具有统计学意义(P<0. 05)。结论:应用丝裂霉素C能够提高顺行泪道引流管置入治疗上泪道阻塞的疗效,改善预后。

关键词：上泪道阻塞顺行泪道引流管置入丝裂霉素C

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国内外双组分纤维的生产现状及发展趋势

合成树脂及塑料 2013年第4期30卷 80-84页

作者：钱鑫中国石油化工股份有限公司北京燕山分公司树脂应用研究所北京市102500

综述了国内外双组分纤维生产状况、发展趋势、加工应用以及生产聚乙烯/聚丙烯皮芯型纤维(ES纤维)所用的主要原料及原料来源。双组分纤维是差别化的纤维,可复合且不损坏纤维内两种聚合物的性能和功能,使复合材料能够表现出单一组分所不... 详细信息

综述了国内外双组分纤维生产状况、发展趋势、加工应用以及生产聚乙烯/聚丙烯皮芯型纤维(ES纤维)所用的主要原料及原料来源。双组分纤维是差别化的纤维,可复合且不损坏纤维内两种聚合物的性能和功能,使复合材料能够表现出单一组分所不能得到的风格、功能和质感。其中,ES纤维是双组分纤维的重要品种,主要应用于卫生领域的热黏合非织造布,其产品具有良好的蓬松性、卷曲性及柔软性,其用量依托中国卫生用品的增长优势迅速扩大。

关键词：双组分纤维聚乙烯聚丙烯皮芯型纤维热黏合非织造布原料应用