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Joint Downlink Scheduling and Radio Resource Allocation for User-Individual QoS in Adaptive OFDMA Wireless Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 1-5页

作者： LU Yan-hui yuan shu-chong YIN Chang-chuan YUE Guang-xin School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This paper proposes and analyzes a downlink multi-carrier proportional fair scheduler and an adaptive radio resource allocation algorithm combining the scheduler. This scheduler and algorithm are suitable for orthogonal frequency division multiple access wireless communication systems supporting multiple quality of service classes. Our results demonstrate that the scheduler and algorithm provide user-explicit fairness with user-individual quality of service guarantees, but the joint schheme achieves a higher sum-rate capacity with flexible parameter settings compared with the multi-carrier proportional fair scheduler.

关键词： OFDMA adaptive radio resource allocation scheduling QoS

Stereoselectivities in α- and β-Amino Acids Catalyzed Mannich Reactions Involving Cyclohexanone

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Chemical Research in Chinese Universities 2011年第4期27卷 673-677页

作者： WANG Ying FU Ai-ping LI Hong-liang TIAN Feng-hui yuan shu-ping SI Hong-zong DUAN Yun-bo WANG Zong-hua Institute for Computational Science and Engineering Laboratory of New Fiber Materials and Modern Textile Growing Base for State Key Laboratory College of Chemical and Environmental Engineering Qingdao University Qingdao 266071 P. R. China

The effects of two different amino acid catalysts on the stereoselectivities in the direct Mannich reactions of cyclohexanone,p-anisidine and p-nitrobenzaldehyde were studied with the aid of density functional *** states of the stereo-determining C ＂C bond-forming step with the addition of enamine intermediate to the imine for the L-proline（·-amino acid） and （R）-3-pyrrolidinecarboxylic acid（·-amino acid）-catalyzed processes were reported.B3LYP/6-31G calculations provide a good explanation for the opposite syn *** diastereoselectivities of these two different kinds of catalysts（syn-selectivity for the ·-amino acid catalysts,anti-selectivity for the ·-amino acid catalysts）.Calculated and observed diastereomeric ratio and enantiomeric excess values are in reasonable agreement.

关键词： Syn-and anti-Mannich reaction Stereoselectivity Amino acid Transition state

CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma

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Chinese Medical Journal 2011年第23期124卷 4083-4085页

作者： LIU Chen LIU Xiao-guang ZHU Bin yuan hui-shu HAN Song-bo MA Yong-qiang Department of Radiology Peking University Third Hospital Beijing 100191 China

Background This study evaluated the feasibility, efficacy and safety of CT-guided percutaneous radiofrequency ablation in patients with spinal osteoid osteoma. Methods Two patients suffered spinal osteoid osteoma were treated with CT-guided percutaneous radiofrequency ablation under local anesthesia. Lesions located in sacral vertebrae and cervical vertebrae, which were adjacent to nerve root and spinal canal respectively. Tumors were treated under 90℃ radiofrequency temperature lasting 4 minutes by an electrode placement. Visual analog scale was used to evaluate the pain improvement. Results No complications were observed pre- and post-operation. Patients recovered to normal activities immediately and achieved complete pain relief in 24 hours. No symptoms were recurrent in 5 months and 4 months follow up. Mild scoliosis has been recovered in case 2. Conclusions CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma is safe, effective and has more clinical benefits. The long-term outcome needs further observation.

关键词： spinal tumor osteoid osteoma CT-guided radiofrequency ablation minimally invasive

Relationship between quantitative magnetic resonance imaging and clinical symptoms in patients with knee osteoarthritis

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Chinese Medical Journal 2020年第14期133卷 1741-1743页

作者： Xin-Guang Wang Li-Xiang Gao Min-Wei Zhao Xiao Geng Tian-Chen Wu hui-shu yuan Hua Tian Department of Orthopaedics Peking University Third HospitalBeijing 100191China Department of Radiology Peking University Third HospitalBeijing 100191China School of Public Health Peking UniversityBeijing 100191China

To the Editor:Quantitative magnetic resonance imaging(MRI)objectively evaluates the degeneration of cartilage in knee osteoarthritis(KOA)patients by measuring changes in proteoglycans,collagen fibers,and water content,thereby facilitating early clinical diagnosis and treatment.[1]Western Ontario and MacMaster Universities(WOMAC)osteoarthritis index score is used to evaluate the symptoms of KOA patients.[2]Presently,few studies have evaluated the correlation between quantitative MRI findings and clinical symptoms(eg.,study performed by Zarins et al[3]).This study explored the relationship between quantitative MRI in T1rho and T2-mapping sequence and WOMAC osteoarthritis index scores of KOA patients.

关键词： patients clinical symptoms

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CT能谱曲线鉴别诊断脊柱肿瘤及肿瘤样病变

中国医学影像技术 2015年第4期31卷 600-603页

作者：袁源张艳郎宁袁慧书北京大学第三医院放射科北京100191

目的探讨CT能谱曲线鉴别诊断脊柱恶性肿瘤与非恶性肿瘤及肿瘤样病变的价值。方法对38例经手术或穿刺病理证实的脊柱肿瘤及肿瘤样病变患者行能谱CT扫描,包括非恶性组18例,其中良性和中间型肿瘤及肿瘤样病变分别为12例和6例;恶性组20例。... 详细信息

目的探讨CT能谱曲线鉴别诊断脊柱恶性肿瘤与非恶性肿瘤及肿瘤样病变的价值。方法对38例经手术或穿刺病理证实的脊柱肿瘤及肿瘤样病变患者行能谱CT扫描,包括非恶性组18例,其中良性和中间型肿瘤及肿瘤样病变分别为12例和6例;恶性组20例。获得单能量图像,生成CT能谱曲线,计算40~140keV不同能级水平下的CT值和能谱曲线斜率。同时获得病变在混合能量图像的静脉期CT值。对所得CT值和能谱曲线斜率进行统计学分析。结果 40~80keV非恶性组CT值分别为（197.97±95.69）HU、（141.30±63.66）HU、（105.78±44.04）HU、（84.21±32.65）HU、（68.92±26.16）HU,恶性组CT值分别为（321.86±97.97）HU、（225.46±72.42）HU、（159.98±50.03）HU、（120.53±41.69）HU、（96.59±37.86）HU。40~80keV条件下,非恶性组与恶性组相同能级CT值差异均有统计学意义（P均〈0.05）;90~140keV条件下,非恶性组与恶性组相同能级CT值差异均无统计学意义（P均〉0.05）。非恶性组能谱曲线斜率为1.58±0.89,低于恶性组能谱曲线斜率（2.76±0.83;t=-3.48,P=0.002）。非恶性组与恶性组混合能量图像的CT值差异无统计学意义（t=-1.19,P=0.250）。结论 CT能谱曲线对鉴别恶性与非恶性脊柱肿瘤及肿瘤样病变有一定价值,具有较好的应用前景。

关键词：脊柱肿瘤体层摄影术,X线计算机诊断,鉴别

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MRI观察成人无骨折、脱位型颈髓损伤

中国医学影像技术 2009年第4期25卷 689-691页

作者：邬海博袁慧书北京大学第三医院放射科北京100083

目的分析成人无骨折、脱位颈椎外伤合并颈脊髓损伤的MR表现及其临床意义。方法收集该病患者38例,入院时均行颈椎X线、CT及MR检查,其中男32例,女6例,年龄24～62岁,平均(42.0±0.4)岁。结果本组病例X线、CT及MR检查均未见颈椎骨折及脱位... 详细信息

目的分析成人无骨折、脱位颈椎外伤合并颈脊髓损伤的MR表现及其临床意义。方法收集该病患者38例,入院时均行颈椎X线、CT及MR检查,其中男32例,女6例,年龄24～62岁,平均(42.0±0.4)岁。结果本组病例X线、CT及MR检查均未见颈椎骨折及脱位。脊髓MRI信号改变包括脊髓信号无改变4例,髓内水肿30例,髓内出血9例,脊髓软化或囊性变4例以及增强后有强化13例。其他MRI表现包括颈椎后纵韧带骨化或颈椎间盘退变或损伤后突出等,为脊髓受压迫的原因。结论MRI可为无骨折、脱位型颈脊髓损伤患者的诊断与正确治疗提供依据。MRI无信号改变或仅有水肿表现者预后较好,髓内出血或者异常强化者预后较差。

关键词：脊髓磁共振成像损伤

CT能谱曲线在脊柱转移瘤和感染性病变中的鉴别诊断价值

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北京大学学报（医学版） 2021年第1期53卷 183-187页

作者：袁源郎宁袁慧书北京大学第三医院放射科北京100191

目的:探讨CT能谱曲线在脊柱转移瘤和感染性病变中鉴别诊断的价值。方法:收集经手术、穿刺组织病理检查或临床治疗证实的29例脊柱转移瘤和18例脊柱感染性病变的能谱CT增强静脉期扫描图像,经后处理获得单能量图像,生成病变感兴趣区(region... 详细信息

目的:探讨CT能谱曲线在脊柱转移瘤和感染性病变中鉴别诊断的价值。方法:收集经手术、穿刺组织病理检查或临床治疗证实的29例脊柱转移瘤和18例脊柱感染性病变的能谱CT增强静脉期扫描图像,经后处理获得单能量图像,生成病变感兴趣区(region of interest,ROI)CT能谱曲线,计算40~140 keV不同能级水平(每10 keV)下的CT值和能谱曲线斜率,同时在传统混合能量图像的同一ROI测量CT值,对所得CT值、能谱曲线斜率及其诊断效能进行统计学分析。结果:脊柱转移瘤和感染性病变的中位年龄分别为58岁和64岁,两组差异无统计学意义(U=171,P=0.4)。40~100 keV各能级下脊柱转移瘤的CT值分别为281.79(143.67,446.19)HU、199.68(100.04,321.49)HU、151.54(81.47,243.49)HU、(122.64±27.72)HU、(99.90±23.88)HU、(85.82±21.61)HU、(75.94±20.27)HU,脊柱感染性疾病的CT值分别为185.29(164.19,277.03)HU、138.44(124.98,238.56)HU、105.46(92.94,169.53)HU、(93.77±15.55)HU、(79.15±12.84)HU、(68.99±11.75)HU、(62.22±11.71)HU。脊柱转移瘤在同一能级的CT值显著高于脊柱感染性病变(P均0.05)。混合能量图像测量的CT值差异无统计学意义(P>0.05)。脊柱转移瘤的能谱曲线斜率为2.43±0.58,高于脊柱感染性疾病的能谱曲线斜率1.50±0.40(P<0.001)。当静脉期能谱曲线斜率阈值取1.72、40 keV CT值取248.80 HU时,曲线下面积分别为0.905、0.892,灵敏度分别为88.0%、80.0%,特异度分别为76.9%、92.3%。结论:CT能谱曲线能够对鉴别脊柱转移瘤及感染性病变提供有价值的半定量信息,可以作为传统CT影像学的补充。

关键词：脊椎肿瘤细菌感染体层摄影术,X线计算机诊断,鉴别

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工程建设中混凝土、砂浆养护的现状分析

中南林学院学报 2005年第5期25卷 117-119页

作者：袁曙辉温州市勘察测绘研究院浙江温州325000

分析了混凝土、砂浆养护在现阶段的实际操作情况,然后用试验说明养护对混凝土质量的影响,并用一砂浆养护失败的工程实例予以验证。认为混凝土、砂浆的养护质量与工程质量息息相关,工程建设中从设计、施工到验收都必须重视混凝土、砂浆... 详细信息

分析了混凝土、砂浆养护在现阶段的实际操作情况,然后用试验说明养护对混凝土质量的影响,并用一砂浆养护失败的工程实例予以验证。认为混凝土、砂浆的养护质量与工程质量息息相关,工程建设中从设计、施工到验收都必须重视混凝土、砂浆的养护。

关键词：混凝土砂浆养护质量

A Prospective Randomized Multicenter Controlled Trial on Salvianolate for Treatment of Unstable Angina Pectoris in A Chinese Elderly Population

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Chinese Journal of Integrative Medicine 2019年第10期25卷 728-735页

作者： CUI Hua LI Xiao-ying GAO Xue-wen LU Xiang WU Xiu-ping WANG Xiao-fei ZHENG Xiang-qing HUANG Kui LIU Feng LUO Zhi yuan hui-shu SUN Gang KONG Jian DU Xiao-hong ZHENG Jin LIU Hong-ying ZHANG Wen-ju Department of Geriatric Cardiology the General Hospital of the People's Liberation Army Beijing (100853) China the Second Department of Cardiology the Second Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine Harbin (150009) China Department of Cardiology Guizhou Province Hospital of Traditional Chinese Medicine Guiyang (550001) China Department of Cadre's Ward the First Bethune Hospital of Jilin University Changchun (130021) China Department of Cadre Health Care the First Affiliated Hospital of Wenzhou Medical University Wenzhou Zhejiang Province (325000) China Medical Department Shanghai Green Valley Pharmaceutical Co. Ltd. Shanghai (201203) China China Health Promotion Foundation Beijing (100161) China Department of Geriatric Clinic Inner Mongolia People's Hospital Hohhot (010017) China Department of Cardiology the Second Affiliated Hospital of Nanjing Medical University Nanjing (210011) China Second Department of Cadre's Ward the First Affiliated Hospital of Harbin Medical University Harbin (150001) China Department of Cadre Health Care Tianjin First Central Hospital Tianjin (300192) China Department of Cardiovascular Medicine Chongqing General Hospital Chongqing (400013) China Department of Geriatrics Shenyang Red Cross Hospital Shenyang (110063) China Department of Geriatric Cardiology Guangzhou First People's Hospital Guangzhou (510180) China Department of Cardiology Beijing Geriatric Hospital Beijing (100095) China

Objective: To evaluate the efficacy and safety of salvianolate in elderly patients with unstable angina pectoris(UAP). Methods: A prospective double-blind randomized placebo-controlled multicenter trial in elderly patients with UAP from 13 third-grade class-A hospitals in China was performed. A total of 318 patients were randomly allocated in a 1:1 ratio to an experimental group(160 patients) and a control group(158 patients). The experimental group was treated with salvianolate for 14 days on the basis of conventional medicine, and the control group was given a placebo for 14 days with the same criteria. Follow-up was lasted 28 days in both groups. The primary endpoint was biweekly frequency of angina pectoris attacks. The secondary endpoints included biweekly dosage of nitroglycerin, the Seattle Angina Questionnaire, angina pectoris severity and duration, myocardial injury markers, high-sensitivity C-reactive protein(hs-CRP) and N-terminal pro-B-type natriuretic peptide(NT-proBNP), as well as major adverse cardiovascular events(MACEs). Safety was assessed according to adverse events and serious adverse events. Results: Baseline characteristics were similar between treatment groups. Compared with those in the control group, the frequency of biweekly angi na attacks(2.92 vs. 4.08, P =0.025), th e biweekly dosage of nitroglycerin, as well as the severity and duration of angina attacks(P <0.01) were reduced by salvianolate. The Seattle Angina Questionnaire score was also significantly improved in the experimental group than in the control group(P <0.05). No significant differences were observed between the two groups with respect to the incidence of MACEs. Salvianolate was well tolerated. Conclusions: Salvianolate appear to have efficacy and well tolerated for elderly patients with UAP.

关键词： Salvianolate unstable angina pectoris elderly efficacy