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一起辐射探伤事故中6名疑似受照人员的医学观察
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作者 王敏 刘玉龙 +6 位作者 卞华慧 王优优 王睿昊 侯雨含 崔冉 杜云 姚振 《国际放射医学核医学杂志》 2019年第2期119-124,共6页
目的通过对一起辐射探伤事故中6名疑似受照人员的临床表现、外照射剂量估算及医学处理的总结,探讨事故成因及后果,为今后类似实践提供技术参考。方法疑似受照人员6名,结合病史问诊、体格检查及实验室检查分析其外周血淋巴细胞染色体“... 目的通过对一起辐射探伤事故中6名疑似受照人员的临床表现、外照射剂量估算及医学处理的总结,探讨事故成因及后果,为今后类似实践提供技术参考。方法疑似受照人员6名,结合病史问诊、体格检查及实验室检查分析其外周血淋巴细胞染色体“双着丝粒+环”畸变及外周血淋巴细胞微核;采用直接测量法估算物理剂量,计算累积剂量;采用焦虑自评量表、抑郁自评量表及卡特尔16项人格测验量表对疑似受照人员进行心理测试,评估其综合心理素质。结果6人临床表现上均有不同程度的不适主诉,体格检查未见明显异常,辅助检查发现几项异常结果,但均与辐射损伤无明显相关;有1人染色体分析细胞数1400中可见1个双着丝粒体,其余均未见异常畸变;物理剂量估算提示周围剂量当量率最大值为20.15mSv/h,辐射累积剂量为0.67mSv;心理测评结果表明有3名人员存在不同程度的焦虑与抑郁状态。结论6名疑似受照人员的各项结果均与电离辐射无关,均未受到急性大剂量电离辐射外照射,不会产生有临床意义的生物效应。 展开更多
关键词 辐射 电离 辐射损伤 辐射剂量 医学处理
Comparison of experimental and theoretical radiation shielding parameters of several environmentally friendly materials 预览
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作者 F. Akman1 O. Agar +1 位作者 M. R. Kacal M. I. Sayyed 《核技术:英文版》 SCIE CAS CSCD 2019年第7期54-61,共8页
In this study, the gamma radiation shielding features of several environmentally friendly materials were investigated. For this purpose, several attenuation parameters, such as the mass attenuation coefficient (l=q), ... In this study, the gamma radiation shielding features of several environmentally friendly materials were investigated. For this purpose, several attenuation parameters, such as the mass attenuation coefficient (l=q), radiation protection efficiency (RPE), and effective atomic number (Zeff) were determined experimentally and compared with numerical data obtained using WinXCom software. In the measurements, the emitted gamma photons were counted by a gamma spectrometer equipped with an HPGe detector using 22Na, 54Mn, 57Co, 60Co, 133Ba, and 137Cs radioactive point sources in the energy region of 81–1333 keV. The obtained results indicate that the l=q and RPE values of the samples decrease with an increase in photon energy. The experimental values are in good agreement with those obtained using WinXCom software. The RPE and Zeff results show that among the studied materials, the NaY0.77Yb0.20Er0.03F4 sample has the best gamma radiation shielding effectiveness. 展开更多
关键词 Greener products RADIATION SHIELDING ATTENUATION COEFFICIENT WinXCom RADIATION protection efficiency
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Preoperative Short-Course Radiation Therapy in Rectal Cancer 预览
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作者 Pham Nguyen Tuong Pham Nguyen Cuong +2 位作者 Le Trong Hung Nguyen Thanh Ai Huynh Thanh Hai 《美中医学:英文版》 2019年第2期100-104,共5页
Purpose:To evaluate the benefits of preoperative short-course radiotherapy in locally advanced rectal cancer.Patients and methods:A prospective study of 30 rectal cancer patients at T3-4M0 stage and ECOG 0-2 performed... Purpose:To evaluate the benefits of preoperative short-course radiotherapy in locally advanced rectal cancer.Patients and methods:A prospective study of 30 rectal cancer patients at T3-4M0 stage and ECOG 0-2 performed preoperative short-course radiation therapy at Hue Central Hospital Vietnam between June 2016 and July 2018,using pelvic 3D-Conformal Radiation Therapy with the total radiation dose being 25 Gy in 5 fractions over five days.Results:Mean age 57.1±13.6 with 46.7%of patients in the range of 41-60 year-old.Male/female ratio:2/1.Tumour stage T3 and T4 was 70%and 30%,respectively;stage III and stage IV was 86.7%and 13.3%,respectively.Positive lymph node rates on endoscopic ultrasound were 85.7%in T3 and 77.8%in T4.Downstaging rate for stage III,T4 and T3 was 65.4%,65.4%and 4.8%,respectively.For upper third of the rectum:100%of T3 stage patients got no downstaging.For middle rectum:downstaging rate for stage III,T4 and T3 was 55.6%,57.1%and 7.1%,respectively.For lower rectum:downstaging rate for stage III,T4 was 50.0%and 100.0%,respectively.No acute toxicity was seen,86.7%of the patients performed laparoscopic sphincter-preserving surgery.Conclusion:For the treatment of locally advanced rectal cancer,neoadjuvant therapy is standard.Preoperative short-course radiation therapy is a reasonable therapeutic option because it demonstrates benefits in tumour downstaging especially for middle and lower rectum. 展开更多
关键词 Rectal cancer short-course RADIATION THERAPY PREOPERATIVE DOWNSTAGING PELVIC 3D-conformal RADIATION therapy.
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Comparison of efficacy and safety between late-course and simultaneous integrated dose-increasing intensity-modulated radiation therapy for cervical cancer complicated with pelvic lymph node metastasis 预览
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作者 Yi Cheng Nan Huang +3 位作者 Jing Zhao Jianhua Wang Chen Gong Kai Qin 《肿瘤学与转化医学:英文版》 2019年第1期25-29,共5页
Objective This study aimed to compare and analyze the clinical efficacy and safety of late-course and simultaneous integrated dose-increasing intensity-modulated radiation therapy(IMRT) for cervical cancer complicated... Objective This study aimed to compare and analyze the clinical efficacy and safety of late-course and simultaneous integrated dose-increasing intensity-modulated radiation therapy(IMRT) for cervical cancer complicated with pelvic lymph node metastasis. Methods Sixty patients with cervical cancer complicated with pelvic lymph node metastasis who were admitted to our hospital from January 2013 to January 2015 were enrolled. The patients were randomly divided into the late-course dose-increasing IMRT group and the simultaneous integrated dose-increasing IMRT group, with 30 cases included in each group, respectively. All patients were concurrently treated with cisplatin. After treatment, the clinical outcomes of the two groups were compared. Results The remission rate of symptoms in the simultaneous integrated dose-increasing IMRT group was significantly higher than that in the late-course dose-increasing IMRT group(P < 0.05). The follow-up results showed that the overall survival time, progression-free survival time, and distant metastasis time of patients in the simultaneous integrated dose-increasing IMRT group were significantly longer than those in the late-course dose-increasing IMRT group(P < 0.05). The recurrent rate of lymph nodes in the radiation field in the simultaneous integrated dose-increasing IMRT group was significantly lower(P < 0.05) than in the late-course dose-increasing IMRT group. There was no significant difference in the incidence of cervical and vaginal recurrence and distant metastasis between the two groups(P > 0.05). The radiation doses of Dmax in the small intestine, D1 cc(the minimum dose to the 1 cc receiving the highest dose) in the bladder, and Dmax in the rectum in the simultaneous integrated dose-increasing IMRT group were significantly lower(P < 0.05) than in the late-course dose-increasing IMRT group. There was no significant difference in intestinal D2 cc(the minimum dose to the 2 cc receiving the highest dose) between the two groups(P > 0.05). The incidence of bone marrow suppr 展开更多
关键词 simultaneous integrated dose-increasing INTENSITY-MODULATED radiation therapy late-course dose-increasing INTENSITY-MODULATED radiation therapy cervical cancer COMPLICATED with pelvic lymph node metastasis clinical efficacy safety
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Efficacy and complications of argon plasma coagulation for hemorrhagic chronic radiation proctitis 预览
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作者 Qing-Hua Zhong Zhan-Zhen Liu +6 位作者 Zi-Xu Yuan Teng-Hui Ma Xiao-Yan Huang Huai-Ming Wang Dai-Ci Chen Jian-Ping Wang Lei Wang 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第13期1618-1627,共10页
BACKGROUND Chronic radiation proctitis (CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there i... BACKGROUND Chronic radiation proctitis (CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there is no literature to date showing any particularly appropriate therapeutic modality for each disease stage. Argon plasma coagulation (APC) is currently recommended as the firstchoice treatment for hemorrhagic CRP, however, its indication based on longterm follow-up is still unclear. On the hypothesis that the long-term efficacy and safety of APC are not fully understood, we reviewed APC treatment for patients with hemorrhagic CRP from a single center. AIM To assess the long-term efficacy and safety of APC for hemorrhagic CRP. METHODS This is a retrospective study of consecutive patients treated with APC for hemorrhagic CRP from January 2013 to October 2017. Demographics, clinical variables, and typical endoscopic features were recorded independently. Success was defined as either cessation of bleeding or only occasional traces of bloody stools with no further treatments for at least 12 mo after the last APC treatment. We performed univariate and multivariate analyses to identify factors associated with success and risk factors for fistulas. RESULTS Forty-five patients with a median follow-up period of 24 mo (range: 12-67 mo) were enrolled. Fifteen (33.3%) patients required blood transfusion before APC. Successful treatment with APC was achieved in 31 (68.9%) patients. The mean number of APC sessions was 1.3 (1-3). Multivariate analysis showed that APC failure was independently associated with telangiectasias present on more than 50% of the surface area [odds ratio (OR)= 6.53, 95% confidence interval (CI): 1.09- 39.19, P = 0.04] and ulcerated area greater than 1 cm^2 (OR = 8.15, 95%CI: 1.63- 40.88, P = 0.01). Six (13.3%) patients had severe complications involving rectal fistulation. The only factor significantly associated with severe complications was ulcerated area greater than 1 cm^2 (P = 0.035). CO 展开更多
关键词 ARGON plasma coagulation CHRONIC RADIATION PROCTITIS RADIATION proctopathy EFFICACY Safety
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Research on Energy Radiation Characteristics of an Airgun Source Excited in Land Reservoir 预览
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作者 DONG Mingrong FU Liyun +3 位作者 XING Chao YANG Shaodong YANG Jun LI Xiaobin 《中国地震研究:英文版》 CSCD 2019年第1期24-36,共13页
The energy radiation process of an airgun seismic source in land reservoir is studied based on the underwater wavelet data collected in the airgun excitation experiments in Binchuan, Yunnan, China. The empirical formu... The energy radiation process of an airgun seismic source in land reservoir is studied based on the underwater wavelet data collected in the airgun excitation experiments in Binchuan, Yunnan, China. The empirical formula for calculating the bubble pulsation period and the maximum radius of the underwater airgun seismic source is obtained. The results show that:① The energy radiation efficiency is higher vertically than horizontally.② The vertical bubble energy radiation efficiency increases with the increase of the air supply pressure.③ The vertical energy radiation efficiency of the airgun seismic source is 9. 4% when the air supply pressure is 15MPa.④ The higher the air supply pressure, the further the propagating distance of the superposition-enhanced pressure wave of an airgun source. 展开更多
关键词 LAND RESERVOIR Airgun seismic SOURCE Shock wave BUBBLE ENERGY Radiation Process
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基于微波诱导定向加热的污泥新型热解方法能耗分析 预览
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作者 王超前 王文龙 +4 位作者 李哲 孙静 宋占龙 赵希强 毛岩鹏 《化工学报》 EI CAS CSCD 北大核心 2019年第A01期168-176,共9页
针对现有污泥热解技术耗时耗能、炭性能受限等难题,提出微波诱导协同热解的新型技术思路,即仅先用常规初级热解获得微波强化吸收的热解基体,再用微波诱导其高能位点效应,以期低能耗制备较高性能的污泥炭。对样品进行介电特性、工业分析... 针对现有污泥热解技术耗时耗能、炭性能受限等难题,提出微波诱导协同热解的新型技术思路,即仅先用常规初级热解获得微波强化吸收的热解基体,再用微波诱导其高能位点效应,以期低能耗制备较高性能的污泥炭。对样品进行介电特性、工业分析等多种测试,在简要分析并验证该思路可行的基础上,探寻其能耗机制,以期为实际应用提供参考。结果表明,通过常规700℃热解10min的热解基体,介电特性提高约22%,可在微波900W中5min升高到平均900℃;不仅提高炭性能,而且比常规700℃热解60min节能省时达50%以上,这主要归因于对热解过程整体用时的显著缩减与微波能的高效利用。研究思路为低能耗制备高附加值污泥炭奠定工艺应用基础,有望实现污泥大规模资源化处置。 展开更多
关键词 废物处理 热解 辐射 市政污泥 微波诱导协同热解 节能
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Improvements in SOD mimic AEOL-10150, a potent broad-spectrum antioxidant
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作者 Xiao-rui Zhang Wen-xia Zhou Yong-xiang Zhang 《军事医学研究:英文版》 CAS CSCD 2019年第1期78-88,共11页
AEOL-10150 is a broad-spectrum metalloporphyrin superoxidase dismutase(SOD) mimic specifically designed to neutralize reactive oxygen and nitrogen species. Research has shown that AEOL-10150 is a potent medical counte... AEOL-10150 is a broad-spectrum metalloporphyrin superoxidase dismutase(SOD) mimic specifically designed to neutralize reactive oxygen and nitrogen species. Research has shown that AEOL-10150 is a potent medical countermeasure against national security threats including sulfur mustard(SM), nerve agent exposure and radiation pneumonitis following a radiological/nuclear incident sufficient to cause acute radiation syndrome(ARS). AEOL-10150 performed well in animal safety studies, and two completed phase 1 safety studies in patients demonstrated that the drug was safe and well tolerated, indicating that AEOL-10150 has potential as a new catalytic antioxidant drug. In this article, we review improvements in AEOL-10150 in preclinical pharmacodynamic studies, especially regarding anti-SM,chlorine gas and radiation exposure studies. 展开更多
关键词 Catalytic ANTIOXIDANT METALLOPORPHYRINS Chemical warfare agent Radiation damage PHARMACODYNAMICS Pharmacokinetics
球面近远场和远近场变换算法 预览
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作者 谢志祥 张云华 +1 位作者 张羽绒 李新 《电波科学学报》 EI CSCD 北大核心 2019年第2期139-144,共6页
天线的远场对于研究天线辐射特性具有重大意义,近场测量技术因其能够避免直接测量远场而得到广泛应用,该技术采用近远场变换获得远场,然而,检验该远场的准确性也是很重要的.为了解决此类问题,文中以球面近场测量为例,提供了一种解决方案... 天线的远场对于研究天线辐射特性具有重大意义,近场测量技术因其能够避免直接测量远场而得到广泛应用,该技术采用近远场变换获得远场,然而,检验该远场的准确性也是很重要的.为了解决此类问题,文中以球面近场测量为例,提供了一种解决方案.该方案主要探讨了球面波模式展开理论,该理论是实现球面近远场变换算法的关键,其将待测天线在空间建立的场展开成球面波函数之和,天线的加权系数既包含了远场信息也包含了近场信息.因此,不仅能够利用近场测量信息获得远场辐射特性,同样能够利用远场辐射特性反推得到近场处电场,这样就能检验由近远场变换算法得到的远场是否准确.文中首先推算得到了近远场变换公式,随后进一步推算得到远近场变换的公式,最后将本文算法计算结果与FEKO测量结果进行比较,二者吻合良好,从而证实了本文两种算法的有效性. 展开更多
关键词 球面波 近场 近远场变换 辐射 加权系数
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Change in Surface Microstructure and Properties of PTFE after Solar Radiation and its Mechanism
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作者 马国政 DING Guangyu +3 位作者 LIU Xuebin 王海斗 ZHAI Huanchun ZHU Hui 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第1期223-229,共7页
A series of solar radiation tests for the polytetrafluoroethylene(PTFE) bulk and film samples were carried out using Q-SUN XE-3-HSC type Solar Radiation Simulator, with the test parameters as follows: radiation intens... A series of solar radiation tests for the polytetrafluoroethylene(PTFE) bulk and film samples were carried out using Q-SUN XE-3-HSC type Solar Radiation Simulator, with the test parameters as follows: radiation intensity is 1 120 W/m~2, temperature is 55 ℃ and humidity is 70% RH. Surface morphology, composition and microstructure of the PTFE samples before and after radiation tests were characterized contrastively. Effect of solar radiation on the tribology and wetting properties of PTFE were also studied by tribometer and contact angle tester, respectively. The results show that, for radiated PTFE, surface roughness, the relative content of C element, the friction coefficients and the contact angle with water increased in varying degrees. In conclusion, the obvious change in PTFE samples can be mainly attributed to break of(CFx)-C bonds after bombardment of high energy UV photons, which causes the loss of F-rich groups, oxidation, crosslinking and restructuring of active unsaturated groups. 展开更多
关键词 SOLAR radiation PTFE microstructure TRIBOLOGICAL PROPERTIES WETTING PROPERTIES
放射线对不同材料充填治疗龋损牙边缘微渗漏的影响 预览
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作者 刘艳 付强 房玉奎 《承德医学院学报》 2019年第2期121-124,共4页
目的:观察放射线照射对Filtek Z350纳米树脂和FX-Ⅱ加强型玻璃离子水门汀充填治疗龋损牙对边缘微渗漏的影响。方法:40颗离体前磨牙随机分为4组,每组10颗,分别为放射线照射A1组和A2组,对照B1组和B2组。40颗离体牙均在颊侧面备洞,A1、B1... 目的:观察放射线照射对Filtek Z350纳米树脂和FX-Ⅱ加强型玻璃离子水门汀充填治疗龋损牙对边缘微渗漏的影响。方法:40颗离体前磨牙随机分为4组,每组10颗,分别为放射线照射A1组和A2组,对照B1组和B2组。40颗离体牙均在颊侧面备洞,A1、B1组样本牙使用Filtek Z350纳米树脂充填窝洞,A2、B2组样本牙使用FX-Ⅱ加强型玻璃离子水门汀充填。A1和A2组样本牙每天进行一次放射线照射,每次2.0Gy,累计总照射剂量为70G y;B1和B2组样本牙不做放射线照射。4组样本经500次冷热循环后,使用2.0%亚甲基蓝溶液染色,体式显微镜下测量每组样本牙的微渗漏值。结果:使用相同充填材料,放射线照射组与对照组微渗漏值比较,差异无统计学意义(P>0.05)。不论是否放射线照射,不同充填材料微渗漏值比较,差异均无统计学意义(P>0.05)。结论:临床上对于准备实施放射治疗的头颈部肿瘤患者,选择Filtek Z350纳米树脂和FX-Ⅱ加强型玻璃离子水门汀充填治疗龋损牙,均能获得较稳定的边缘密封效果。 展开更多
关键词 放射线 微渗漏 充填材料 纳米树脂 玻璃离子水门汀
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《医疗卫生用品辐射灭菌消毒质量控制》实施情况调查
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作者 谈智 徐燕 +5 位作者 王玲 范晶晶 王春雷 陈学良 吴晓松 李炎 《中国消毒学杂志》 CAS 2019年第5期348-351,共4页
目的对GB 16383-2014《医疗卫生用品辐射灭菌消毒质量控制》实施情况进行调查,为标准的修订提供科学依据。方法采用问卷调查、文献查阅、专家咨询等方式,对收集的意见进行汇总、统计和分析。结果辐射灭菌企业与检测机构对标准的知晓率... 目的对GB 16383-2014《医疗卫生用品辐射灭菌消毒质量控制》实施情况进行调查,为标准的修订提供科学依据。方法采用问卷调查、文献查阅、专家咨询等方式,对收集的意见进行汇总、统计和分析。结果辐射灭菌企业与检测机构对标准的知晓率分别为92. 86%和83. 33%,接受标准宣贯的培训率分别为0%和23. 33%;辐射灭菌企业对条款适用性的认可度为64. 29%~92. 86%,对部分条款合理性认可在'可接受'程度以上的达100%,其他部分条款合理性认可在'可接受'程度以上的占64. 29%~85. 71%;检测机构对相关条款适用性与合理性的认可在'可接受'程度以上的达100%。结论标准宣贯与培训不够,需要加强宣贯培训;加强多部门合作,适时修订,提高标准的协调性、适用性。 展开更多
关键词 辐射 灭菌 消毒 质量控制 标准 实施情况调查
探究放射线和CT对肺段隔离症疾病的临床诊断价值
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作者 吕志胜 《智慧健康》 2019年第9期5-6,共2页
目的分析放射线和CT对肺段隔离症疾病的临床诊断价值。方法随机选取本院2015年11月至2018年10月收治的肺段隔离症疾病患者61例,所有患者均需进行放射线和CT检查诊断,回顾分析检查诊断结果。结果经放射线检查确诊的有54例,诊断准确率为88... 目的分析放射线和CT对肺段隔离症疾病的临床诊断价值。方法随机选取本院2015年11月至2018年10月收治的肺段隔离症疾病患者61例,所有患者均需进行放射线和CT检查诊断,回顾分析检查诊断结果。结果经放射线检查确诊的有54例,诊断准确率为88.52%,经CT检查确诊的有60例,诊断准确率为98.36%,两者诊断准确率对比存在较大差异(P<0.05)。结论 CT对肺段隔离症疾病的临床诊断价值明显高于放射线,且能够清晰显示出患者肺部组织,具有准确率高、图像质量高的特点,值得大量推广应用在肺段隔离症疾病临床诊断上。 展开更多
关键词 放射线 CT 肺段隔离症疾病 诊断准确率
Phylogenetic relationships of Cypriniformes and plasticity of pharyngeal teeth in the adaptive radiation of cyprinids
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作者 Wenjing Tao Lei Yang +1 位作者 Richard L.Mayden Shunping He 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第4期553-565,共13页
The Cypriniformes comprise approximately 4,200 species accounting for 25% of the diversity of all freshwater fish,which is widely distributed across the world’s continents except Antarctica,South America,and Australi... The Cypriniformes comprise approximately 4,200 species accounting for 25% of the diversity of all freshwater fish,which is widely distributed across the world’s continents except Antarctica,South America,and Australia.The highest species diversity is found in Southeastern Asia.Despite its remarkable species diversity and broad-scale geographic patterns of distribution,the evolutionary history of this major freshwater fish group remains largely unresolved.To gain insight of the evolutionary history of Cypriniformes,we present a phylogeny of this group using 1 mitochondrial gene and 15 nuclear genes comprising a total of14,061 bp.Bayesian inference using all gene fragments yielded a well resolved phylogeny,which is mostly consistent with topologies obtained from Maximum Likelihood analyses.Our results further confirmed the monophyly of Cypriniformes and seven constituent subclades including Cyprinidae,Catostomidae,Gyrinocheilidae,Balitoridae,Cobitidae,Nemacheilidae,and Botiidae.Bayesian divergence time analysis indicated that the origin of the Cypriniformes was about 193 Mya during the early Jurassic,coinciding with the onset of the Pangaea breakup.The basal divergence of Cypriniformes is 154 Mya during the late Jurassic.Our findings from molecular divergence and biogeographical analysis indicate the most likely initial geographical range of the ancient Cypriniformes was both East and South Asia(Southeastern area of Mesozoic Laurasia).Moreover,the burst in species diversity in Cyprinidae afforded by the nearly worldwide colonization is possibly in response to the plasticity of pharyngeal dentition.The present study demonstrates that the Cypriniformes was about 193 Mya during the early Jurassic,coinciding with the onset of the Pangaea breakup.The plasticity of pharyngeal dentition of cyprinids might contribute to the burst and radiation of this lineage.The phylogenetic and biogeographic analyses in this study help to improve our understanding of the evolutionary history of this diverse and important freshwater fis 展开更多
关键词 PHYLOGENY biogeographic analyses CYPRINIFORMES PHARYNGEAL teeth adaptive radiation
Synchrotron infrared spectral regions as signatures for foodborne bacterial typing 预览
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作者 Ya-Di Wang Xue-Ling Li +1 位作者 Jun Hu Jun-Hong Lu 《核技术:英文版》 SCIE CAS CSCD 2019年第2期109-113,共5页
Fourier-transform infrared (FTIR) spectroscopy has emerged as a viable alternative to biochemical and molecular biology techniques for bacterial typing with advantages such as short analysis time, low cost and laborat... Fourier-transform infrared (FTIR) spectroscopy has emerged as a viable alternative to biochemical and molecular biology techniques for bacterial typing with advantages such as short analysis time, low cost and laboratorial simplicity. In this study, synchrotron radiationbased FTIR (SR-FTIR) spectroscopy with higher spectral quality was successfully applied to type 16 foodborne pathogenic bacterial strains. Combined with principal comp on ent analysis (PCA) and hierarchical cluster analysis (HCA), we found that the specific spectral region 1300-1000cm^-1, which reflects the in formation of phosphate compounds and polysaccharides, can be used as the signature region to cluster the strains into groups similar with genetic taxonomic method. These findings demonstrated that FTIR spectra combined with HCA have a great potential in quickly typing bacteria depending on their biochemical signatures. 展开更多
关键词 SYNCHROTRON radiation FTIR Spectral signature BACTERIAL TYPING PCA HCA
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Effect of Modified Wuzi Yanzong Pill(五子衍宗丸) on Tip60-Mediated Apoptosis in Testis of Male Rats after Microwave Radiation
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作者 HU Hai-xiang SUN Jing +8 位作者 GAO Ya-jing FANG Hong XU Shao-qiang DONG Jing WEI Li-zhao LUO Shao-bo SHEN Chuan-yun ZHANG Qi-long XIE Ya-lan 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第5期342-347,共6页
Objective: To investigate the effect of a modi?ed Wuzi Yanzong Pill(五子衍宗丸, WZYZP) on the male rats’ testis after microwave radiation, as well as its potential mechanism. Methods: Forty-?ve male rats were randoml... Objective: To investigate the effect of a modi?ed Wuzi Yanzong Pill(五子衍宗丸, WZYZP) on the male rats’ testis after microwave radiation, as well as its potential mechanism. Methods: Forty-?ve male rats were randomly assigned to three groups: the control group, the radiation group, and the WZYZP group. The rats in the radiation group and WZYZP group were exposed to microwave radiation for 15 min once, while the rats in the control group were not exposed to any radiation. The rats in the WZYZP group were given a modi?ed of WZYZP by gavage daily for 7 days. Apoptosis in the testis was evaluated using terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) assay. Histopathological alterations of the testis were observed by haematoxylin-eosin(HE) staining. Tat-interactive protein, 60 kD(Tip60) and p53 expressions were determined by Western blotting. Results: The apoptosis index(AI) in the radiation group was higher than that of the WZYZP group and control group on day 1(D1), day 7(D7) day 14(D14) after radiation(P<0.05). The seminiferous tubules were of normal morphology in the control group. In the radiation group, the partial seminiferous tubules were collapsed, basement membranes of the seminiferous epithelia became detached. WZYZP could restore the morphological changes. There was no expression of Tip60 among the three groups on D7 and D14. The expression of p53 was higher in the radiation group than in the control group(P<0.05). WZYZP could down-regulate the rising p53 induced by radiation on D7 and D14(P<0.05). Conclusion: A modified WZYZP may affect germ cells, and its protective effects may partly result from its ability to intervene in Tip60 mediated apoptosis. 展开更多
关键词 MICROWAVE electromagnetic radiation SPERMATOGENESIS apoptosis HISTONE acetyltransferases
冠状动脉成像中采用常规扫描和能谱低剂量扫描对图像质量和辐射剂量的影响 预览
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作者 杨保智 侯浩宇 +2 位作者 康眼训 杜鑫 任倩 《临床医学研究与实践》 2019年第5期8-9,12共3页
目的探讨冠状动脉成像中采用常规扫描和能谱低剂量扫描方案对图像质量和辐射剂量的影响。方法收集因病情行冠状动脉成像的86例患者的临床资料,根据所用扫描模式的不同将其分为能谱组和常规组,每组43例。能谱组采用宝石能谱SSA低剂量扫... 目的探讨冠状动脉成像中采用常规扫描和能谱低剂量扫描方案对图像质量和辐射剂量的影响。方法收集因病情行冠状动脉成像的86例患者的临床资料,根据所用扫描模式的不同将其分为能谱组和常规组,每组43例。能谱组采用宝石能谱SSA低剂量扫描模式,常规组采用普通扫描模式。比较两组图像质量和辐射剂量。结果两组的主观评分、ASCT值、SD、CNR及SNR比较,差异不具有统计学意义(P>0.05)。能谱组的DLP、CTDIvol及ED均显著低于常规组,差异均具有统计学意义(P<0.05);能谱组的ED较常规组降低约25%。结论冠状动脉成像中采用能谱低剂量扫描方案能够有效降低辐射剂量并获得理想的图像质量。 展开更多
关键词 X线计算机 辐射 冠状动脉 体层摄影
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三能级ASE光源在辐射环境下的增益损耗建模
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作者 田亚 金靖 +1 位作者 张浩石 范海涛 《激光杂志》 北大核心 2019年第3期20-22,共3页
对三能级自发辐射放大(ASE)光源在辐射环境下的增益损耗进行了建模研究。以掺铒光纤(EDF)为主要研究对象,基于色心的动力学理论,利用低剂量下的增益损耗,获得了ASE光源增益损耗建模所需要的辐射吸收参数。然后采用自验证的方式,利用高... 对三能级自发辐射放大(ASE)光源在辐射环境下的增益损耗进行了建模研究。以掺铒光纤(EDF)为主要研究对象,基于色心的动力学理论,利用低剂量下的增益损耗,获得了ASE光源增益损耗建模所需要的辐射吸收参数。然后采用自验证的方式,利用高剂量下的增益损耗数据验证了此种建模思想的正确性。此种方法不仅简化了辐射测量装置,同时将铒离子的吸收和光褪色效应对辐射吸收参数的测量造成的误差考虑在内,使得剂量和剂量率的外推更加准确和灵活。结果表明,在低剂量处实验数据与ASE光源增益损耗模型的拟合度达到99. 98%,并且在此拟合度下获得的色心吸收参数在高剂量处的自验证也具有很好的拟合效果,从而进一步证明了此方法的准确性。 展开更多
关键词 光纤光源 辐射 增益损耗 建模 自验证
2016年夏季北冰洋浮冰站近地层辐射和湍流通量观测 预览
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作者 沈辉 杨清华 +3 位作者 孙启振 孙晓宇 赵杰臣 张林 《海洋学报》 CAS CSCD 北大核心 2019年第3期12-22,共11页
2016年8月7-14日中国第七次北极科学考察期间,在83°N附近设立的长期浮冰站开展了辐射和湍流通量观测研究。结果表明,观测期间反照率变化范围为0.64~0.92,平均反照率为0.78;基于现场观测数据评估了PW79、HIRHAM、ARCSYM和CCSM34种... 2016年8月7-14日中国第七次北极科学考察期间,在83°N附近设立的长期浮冰站开展了辐射和湍流通量观测研究。结果表明,观测期间反照率变化范围为0.64~0.92,平均反照率为0.78;基于现场观测数据评估了PW79、HIRHAM、ARCSYM和CCSM34种不同复杂度的反照率参数化方案在天气尺度的表现,最为复杂的CCSM3结果优于其他参数化方案,但不能体现降雪条件下的反照率快速增长。浮冰区冰雪面平均净辐射为18.10W/m^2,平均感热通量为1.73W/m^2,平均潜热通量为5.55W/m^2,海冰表面消融率为(0.30±0.22)cm/d,表明此时北冰洋浮冰正处于快速消融期。冰面的平均动量通量为0.098(kg·m/s)/(m^2·s),动量通量与风速有很好的对应关系,相关系数达0.80。 展开更多
关键词 北冰洋 湍流通量 辐射 反照率 参数化
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平面辐射式制热在室内采暖领域的应用 预览
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作者 张耘 李万勇 陈江平 《建筑热能通风空调》 2019年第5期74-79,88共7页
随着“煤改电”项目在我国北方城市的不断推进,传统电采暖设施暴露出效率低下、成本高昂等问题,平面辐射式制热凭借加热能效高、舒适性好的特点开始得到应用与重视。本文的研究对象为一种以热管原理为基础的平板制热末端,通过实验探究... 随着“煤改电”项目在我国北方城市的不断推进,传统电采暖设施暴露出效率低下、成本高昂等问题,平面辐射式制热凭借加热能效高、舒适性好的特点开始得到应用与重视。本文的研究对象为一种以热管原理为基础的平板制热末端,通过实验探究了其综合制热效果,并建立仿真模型将辐射式采暖方式与传统的电热器(电油汀)及空调采暖方式进行对比。实验结果显示,辐射式制热能在较低功率下使室内温度达到20℃以上,达到相应的室内采暖标准。仿真结果显示在功率同为1 kW的条件下加热15 m~2的房间1小时,辐射式制热方式能使房间平均温度上升9.74℃,相较于电热器的8.17℃提升了19.22%且与电热空调所提升的10.12℃相当。 展开更多
关键词 辐射 室内采暖 热管
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