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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
SOME PROBLEMS IN RADIATION TRANSPORT FLUID MECHANICS AND QUANTUM FLUID MECHANICS
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作者 Boling Guo Jun Wu 《应用数学年刊:英文版》 2019年第2期111-125,共15页
We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport flu... We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport fluid mechanics equations under certain initial and boundary values. In addition, we also obtain the periodic region problem of the compressible N-S equation with quantum effect has weak solutions under some conditions. 展开更多
关键词 RADIATION transport equation RADIATION FLUID MECHANICS EQUATIONS FLUID MECHANICS EQUATIONS with QUANTUM effects
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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Study of backward terahertz radiation from intense picosecond laser-solid interactions using a multichannel calorimeter system
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作者 H.Liu G.-Q.Liao +12 位作者 Y.-H.Zhang B.-J.Zhu Z.Zhang Y.-T.Li G.G.Scott D.Rusby C.Armstrong E.Zemaityte P.Bradford N.Woolsey P.Huggard P.McKenna D.Neely 《高功率激光科学与工程:英文版》 CAS CSCD 2019年第1期47-53,共7页
A multichannel calorimeter system is designed and constructed which is capable of delivering single-shot and broadband spectral measurement of terahertz(THz)radiation generated in intense laser-plasma interactions.The... A multichannel calorimeter system is designed and constructed which is capable of delivering single-shot and broadband spectral measurement of terahertz(THz)radiation generated in intense laser-plasma interactions.The generation mechanism of backward THz radiation(BTR)is studied by using the multichannel calorimeter system in an intense picosecond laser-solid interaction experiment.The dependence of the BTR energy and spectrum on laser energy,target thickness and pre-plasma scale length is obtained.These results in dicate that cohere nt transition radiation is responsible for the low-frequency component(<1 THz)of BTR.It is also observed that a large-scale pre-plasma primarily enhances the high-frequency component(>3 THz)of BTR. 展开更多
关键词 MULTICHANNEL CALORIMETER BACKWARD TERAHERTZ radiation generation MECHANISMS
Optimizing radiotherapy with immune checkpoint blockade in hepatocellular carcinoma 预览
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作者 Changhoon Choi Gyu Sang Yoo +1 位作者 Won Kyung Cho Hee Chul Park 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第20期2416-2429,共14页
Hepatocellular carcinoma (HCC) is the fifth most common cancer, and its incidence is rapidly increasing in North America and Western Europe as well as South-East Asia. Patients with advanced stage HCC have very poor o... Hepatocellular carcinoma (HCC) is the fifth most common cancer, and its incidence is rapidly increasing in North America and Western Europe as well as South-East Asia. Patients with advanced stage HCC have very poor outcomes;therefore, the discovery of new innovative approaches is urgently needed. Cancer immunotherapy has become a game-changer and revolutionized cancer treatment. A comprehensive understanding of tumor-immune interactions led to the development of immune checkpoint inhibitors (ICIs) as new therapeutic tools, which have been used with great success. Targeting immune checkpoint molecules such as programmed cell death-1 (PD-1) and cytotoxic T lymphocyteassociated protein-4 (CTLA-4) reinvigorates anti-tumor immunity by restoring exhausted T cells. Despite their effectiveness in several types of cancer, of the many immune suppressive mechanisms limit the efficacy of ICI monotherapy. Radiation therapy (RT) is an essential local treatment modality for a broad range of malignancies, and it is currently gaining extensive attention as a promising combination partner with ICIs because of its ability to trigger immunogenic cell death. The efficacy of combination approaches using RT and ICIs has been well documented in numerous preclinical and clinical studies on various types of cancers but not HCC. The application of ICIs has now expanded to HCC, and RT is recognized as a promising modality in HCC. This review will highlight the current roles of PD-1 and CTLA-4 therapies and their combination with RT in the treatment of cancers, including HCC. In addition, this review will discuss the future perspectives of the combination of ICIs and RT in HCC treatment. 展开更多
关键词 HEPATOCELLULAR carcinoma Radiation therapy IMMUNE CHECKPOINT INHIBITORS Abscopal effect
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长三角地区气溶胶对辐射和降水影响的分析
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作者 陆天蔚 张晶 +2 位作者 乔岩 薛文晧 周丽花 《北京师范大学学报:自然科学版》 CAS CSCD 北大核心 2019年第1期135-144,共10页
为深入研究长三角地区气溶胶对辐射和降水的影响,本文分析了2004—2014年该区气溶胶光学厚度(aerosol optical depth,AOD)、辐射和降水的时空变化特征,在季节尺度确定了对辐射和降水影响最大的气溶胶成分.研究发现:2004—2008年,AOD在... 为深入研究长三角地区气溶胶对辐射和降水的影响,本文分析了2004—2014年该区气溶胶光学厚度(aerosol optical depth,AOD)、辐射和降水的时空变化特征,在季节尺度确定了对辐射和降水影响最大的气溶胶成分.研究发现:2004—2008年,AOD在春、夏季明显上升(0.260·(10a)-1、0.066·(10a)-1),辐射在春季明显上升(20.4 W·m-2·(10a)-1))、夏季明显下降(-41.4W·m-2·(10a)-1)),降水在夏季明显上升(4.6mm·(10a)-1)、冬季明显下降(-1.7mm·(10a)-1);2009—2014年秋季AOD明显下降(-0.126·(10a)-1),辐射和降水无明显变化趋势.2004—2014年辐射在春、夏季受云量和气溶胶共同影响,2004—2008年秋、冬季辐射主要受AOD影响,2009—2014年秋、冬季辐射与云量相关性更高.各季节沙尘、海盐气溶胶的AOD小于总AOD的20%,但其对辐射和降水影响更大.春、夏季对辐射影响最大的气溶胶分别是细模态沙尘和细模态海盐;降水在春、夏、冬季均受沙尘气溶胶影响最大. 展开更多
关键词 AOD 辐射 降水
Pressure-induced isostructural phase transition in α-Ni(OH)2 nanowires
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作者 马鑫 李志慧 +9 位作者 荆晓玲 顾宏凯 田辉 董青 王鹏 刘然 刘波 李全军 姚震 刘冰冰 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期332-337,共6页
High pressure structural phase transition of monoclinic paraotwayite type α-Ni(OH)2 nanowires with a diameter of15 nm–20 nm and a length of several micrometers were studied by synchrotron x-ray diffraction(XRD) and ... High pressure structural phase transition of monoclinic paraotwayite type α-Ni(OH)2 nanowires with a diameter of15 nm–20 nm and a length of several micrometers were studied by synchrotron x-ray diffraction(XRD) and Raman spectra.It is found that the α-Ni(OH)2 nanowires experience an isostructural phase transition associated with the amorphization of the H-sublattice of hydroxide in the interlayer spaces of the two-dimensional crystal structure at 6.3 GPa–9.3 GPa. We suggest that the isostructural phase transition can be attributed to the amorphization of the H-sublattice. The bulk moduli for the low pressure phase and the high pressure phase are 41.2(4.2) GPa and 94.4(5.6) GPa, respectively. Both the pressure-induced isostructural phase transition and the amorphization of the H-sublattice in the α-Ni(OH)2 nanowires are reversible upon decompression. Our results show that the foreign anions intercalated between the α-Ni(OH)2 layers play important roles in their structural phase transition. 展开更多
关键词 nickel HYDROXIDE high pressure SYNCHROTRON radiation ISOSTRUCTURAL phase transition
槽式太阳能集热管的优化设计 预览
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作者 孙宇 王沛 《现代工业经济和信息化》 2019年第7期31-33,46共4页
以槽式太阳能集热管径向截面的二维模型作为研究对象,采用与环形空腔自然对流换热经典实验相同的参数进行在“真空完好”工况下,模拟不同半径比对于集热效率的影响。研究表明:对于“真空完好”情况下,半径比越小集热效率越高;对于环形腔... 以槽式太阳能集热管径向截面的二维模型作为研究对象,采用与环形空腔自然对流换热经典实验相同的参数进行在“真空完好”工况下,模拟不同半径比对于集热效率的影响。研究表明:对于“真空完好”情况下,半径比越小集热效率越高;对于环形腔,由于其间几乎只存在辐射换热,因此温度分布都较为均匀不存在局部的特殊性;对于不同半径比,辐射热损的整体趋势线随着半径比的增大而上升;2.43、1.5和1.286三种半径比下的集热管内管的温度分布基本相同。 展开更多
关键词 太阳能 槽式 集热效率 辐射 数值模拟
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Is the enhancement of type Ⅱ radio bursts during CME interactions related to the associated solar energetic particle event?
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作者 Liu-Guan Ding Zhi-Wei Wang +2 位作者 Li Feng Gang Li Yong Jiang 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2019年第1期47-60,共14页
We investigated 64 pairs of interacting-CME events identified from simultaneous observations by the SOHO and STEREO spacecraft from January 2010 to August 2014, to examine the relationship between large SEP events in ... We investigated 64 pairs of interacting-CME events identified from simultaneous observations by the SOHO and STEREO spacecraft from January 2010 to August 2014, to examine the relationship between large SEP events in the energy range of ~25 to~60 MeV and properties of the interacting CMEs.We found that during CME interactions, the large SEP events in this study were all generated by CMEs with the presence of enhanced type Ⅱ radio bursts, which also have wider longitudinal distributions compared to events without a type Ⅱ radio burst or its enhancement(almost always associated with small SEP events).It seems that the signature of type Ⅱ radio burst enhancement is a good discriminator between large SEP and small or no SEP event producers during CME interactions. The type Ⅱ radio burst enhancement is more likely to be generated by CME interactions, with the main CME having a larger speed(v), angular width(WD), mass(m) and kinetic energy(Ek), and taking over the preceding CMEs. The preceding CMEs in these instances have higher v, WD, m and Ekthan those in CME pairs missing type Ⅱ radio bursts or enhancements. Generally, the values of these properties in the type-Ⅱ-enhanced events are typically higher than the corresponding non-type-Ⅱ or non-type-Ⅱ-enhanced cases for both the main and preceding CMEs. Our analysis also revealed that the intensities of associated SEP events correlate negatively with the intersection height of the two CMEs. Moreover, the overlap width of two CMEs is typically larger in type-Ⅱ-enhanced events than in non-type-Ⅱ or non-type-Ⅱ-enhanced events. Most type-Ⅱ-enhanced events and SEP events are coincident and are almost always made by the fast and wide main CMEs that sweep fully over relatively slower and narrower preceding CMEs. We suggest that a fast CME with enough energy completely overtaking a relatively narrower preceding CME, especially at low height, can drive a more energetic shock signified by the enhanced type Ⅱ radio bursts. The shock may accelerate ambient 展开更多
关键词 Sun:coronal mass ejections(CMEs) Sun:radio radiation Sun:particle emission Sun:CME interaction
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不同职业放射暴露环境工作人员染色体和微核发生变化的影响因素分析
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作者 赖专华 庄贵华 +2 位作者 武永平 张克俭 杨海峰 《实用预防医学》 CAS 2019年第7期827-831,共5页
目的探讨不同职业放射暴露环境工作人员外周血淋巴细胞染色体发生畸变和微核发生变化的危险因素,为评价各类职业放射暴露环境工作人员健康水平提供依据。方法收集2012年宝鸡市372名职业放射暴露环境工作人员(医用X线诊断139名,工业探伤... 目的探讨不同职业放射暴露环境工作人员外周血淋巴细胞染色体发生畸变和微核发生变化的危险因素,为评价各类职业放射暴露环境工作人员健康水平提供依据。方法收集2012年宝鸡市372名职业放射暴露环境工作人员(医用X线诊断139名,工业探伤106名,烟厂卷接工95名,工业同位素应用32名)的一般人口学、工龄、职业放射暴露环境及染色体和微核变化的数据。采用χ^2检验、多因素logistic回归等方法进行统计分析。结果不同年龄组职业放射暴露环境工作人员的微核率之间差异有统计学意义(P<0.05)。不同工龄组的ace畸变率、染色体型畸变率、染色体畸变总率和微核率之间差异有统计学意义(P<0.001);不同职业放射暴露环境工作人员的无着丝粒断片(acentricfragment,ace)畸变率和染色体型畸变率差异有统计学意义(P<0.05)。年龄和放射工龄是职业放射暴露环境工作人员发生ace畸变(OR=1.064,95%CI:1.018~1.112)、染色体型畸变(OR=1.064,95%CI:1.021~1.108)、染色体总畸变(OR=1.038,95%CI:1.006~1.071)和外周血淋巴细胞产生微核(OR=1.064,95%CI:1.037~1.091)的危险因素,随着年龄和放射工龄增加,其发生ace畸变、染色体型畸变、染色体总畸变和外周血淋巴细胞产生微核的风险增加。烟厂卷接工的放射暴露环境是发生染色体型畸变、染色单体畸变和染色体总畸变的危险因素。烟厂卷接工发生ace畸变、染色体型畸变、染色单体畸变和染色体总畸变的危险分别是医用X线诊断的3.679(95%CI:1.310~10.335)、3.637(95%CI:1.405~9.413)、3.649(95%CI:1.488~8.951)、3.794(95%CI:1.795~8.017)倍。人均年有效剂量与职业放射暴露环境工作人员外周血淋巴细胞发生变化无关。结论职业放射暴露环境对工作人员的外周血淋巴细胞产生一定的影响。年龄和放射工龄也与外周血淋巴细胞发生改变有关。与其他职业放射暴露环境相比,烟厂卷接工作� 展开更多
关键词 放射 职业暴露 染色体畸变 微核 危险因素
电子束转靶X射线对红花石蒜、韭兰的诱变效应 预览
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作者 刘玲 王丹 +8 位作者 闵可怜 陈敏 黎熠睿 湛晓蝶 杨青青 崔正旭 田甲 陈浩 黄敏 《西南农业学报》 CSCD 北大核心 2019年第3期620-626,共7页
【目的】本试验以研究电子束转靶X射线对红花石蒜、韭兰的辐射诱变效应为目的。【方法】以剂量分别为25、50、75、100Gy,能量为2MeV10 Ma的电子束转靶X射线辐照红花石蒜和韭兰种球,统计分析辐照后的发芽率、株高、叶片数量、叶片面积、... 【目的】本试验以研究电子束转靶X射线对红花石蒜、韭兰的辐射诱变效应为目的。【方法】以剂量分别为25、50、75、100Gy,能量为2MeV10 Ma的电子束转靶X射线辐照红花石蒜和韭兰种球,统计分析辐照后的发芽率、株高、叶片数量、叶片面积、根长、根数、可溶性糖、还原糖及淀粉含量。【结果】不同剂量的辐照对植株均有损伤效应,主要表现为发芽滞后,植株变矮,叶片数量变少,叶面积减小,根长变短,根的数量减少;处理组可溶性糖和淀粉含量均大于对照组,红花石蒜的还原糖含量低于对照组,韭兰的还原糖随着辐照剂量的升高呈现出先下降再上升趋势。处理组之间的生长指标无显著性差异,展现出来的形态特征相似,但处理组与对照组之间差异较大,红花石蒜和韭兰在经电子束转靶X射线辐照后生长均受到抑制。【结论】本研究主要探索不同剂量的电子束转靶X射线对红花石蒜、韭兰的生长发育影响,以期为成功选育新品种奠定基础,为辐照诱变育种提供参考。 展开更多
关键词 红花石蒜 韭兰 电子束转靶X 射线 辐射 种球
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低本底实验室特种混凝土结构施工技术
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作者 杜小乐 李松伟 +3 位作者 丁益民 杨旭东 崔婧瑞 苏岩 《施工技术》 CAS 2019年第4期129-132,共4页
以国家核与辐射安全监管技术研发基地建设项目低本底实验室特种混凝土结构施工作为工程实例,通过筛选本底值低的建筑材料及材料性能参数控制、优化混凝土试配、改善混凝土工作性能、选用高强度精品模板、优化支撑体系及模板加固、优化... 以国家核与辐射安全监管技术研发基地建设项目低本底实验室特种混凝土结构施工作为工程实例,通过筛选本底值低的建筑材料及材料性能参数控制、优化混凝土试配、改善混凝土工作性能、选用高强度精品模板、优化支撑体系及模板加固、优化混凝土施工工艺等措施,确保本底值控制,提高混凝土工作性稳定,实现超厚墙体和顶板一次浇筑,保证了混凝土结构密实度和平整度,垂直度及裂缝控制,实现低本底特种混凝土结构施工一次成优。 展开更多
关键词 混凝土 特种混凝土 辐射 低本底 实验室 施工技术
沉默APE1对非小细胞肺癌细胞的放射敏感性的影响研究
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作者 欧俞宏 李轶 +1 位作者 刘琴 王永生 《四川大学学报:医学版》 CAS CSCD 北大核心 2019年第1期1-6,共6页
目的研究脱嘌呤脱嘧啶核酸内切酶-1(APE1)对非小细胞肺癌细胞放射敏感性的影响。方法采用免疫组化染色检测手术标本切片(非小细胞肺癌组织20例及癌旁组织5例)中APE1的表达,Western blot与实时荧光定量(qRT)-PCR检测非小细胞肺癌细胞系(A... 目的研究脱嘌呤脱嘧啶核酸内切酶-1(APE1)对非小细胞肺癌细胞放射敏感性的影响。方法采用免疫组化染色检测手术标本切片(非小细胞肺癌组织20例及癌旁组织5例)中APE1的表达,Western blot与实时荧光定量(qRT)-PCR检测非小细胞肺癌细胞系(A549,H460,H1299)及肺正常上皮细胞系中APE1的表达;Western blot检测辐照A549与H460细胞0~6Gy后APE1的表达;构建沉默APE1的A549与H460稳定细胞株后,Western blot检测其辐照6Gy后APE1的蛋白表达;细胞克隆形成实验检测细胞克隆形成率;CCK-8检测细胞增殖;细胞术流式检测细胞凋亡。结果非小细胞肺癌组织及细胞系中APE1的表达明显上调;辐照能诱导非小细胞肺癌细胞APE1的表达,且表达随辐照剂量增高而上调;沉默APE1能有效地抑制辐照诱导A549与H460细胞中APE1的表达;成功构建沉默APE1的A459、H460稳定细胞株;沉默APE1联合辐照进一步抑制了非小细胞肺癌细胞克隆形成率、细胞增殖率,同时促进细胞凋亡(P<0.05),且呈随辐照剂量增高改变的趋势。结论沉默APE1可增强非小细胞肺癌细胞的放射敏感性。 展开更多
关键词 APE1 非小细胞肺癌 辐照 克隆形成 增殖 凋亡
Effect of Electromagnetic Radiation on the Growth and Development of Euproctis pseudoconspersa Strand 预览
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作者 Chunjiang SHUAI 《农业生物技术:英文版》 CAS 2019年第2期124-127,132共5页
The principal component method is to recombine multiple correlated indexes into a group of non-correlated comprehensive indexes to replace the original indexes for evaluation. The paper took the test data of growth an... The principal component method is to recombine multiple correlated indexes into a group of non-correlated comprehensive indexes to replace the original indexes for evaluation. The paper took the test data of growth and development of Euproctis pseudoconspersa Strand as a basis and used the principal component analysis method to analyze and investigate the test data. The research results indicate that the principal component analysis method is a model with actual operation value and evaluation reliability. When the electromagnetic radiation is higher than 100 K, the growth and development indexes of E. pseudoconspersa Strand are correlated to electromagnetic radiation frequency to some extent. 展开更多
关键词 ELECTROMAGNETIC RADIATION Euproctis pseudoconspersa STRAND GROWTH and DEVELOPMENT
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Geoengineering and the blockchain: Coordinating Carbon Dioxide Removal and Solar Radiation Management to tackle future emissions
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作者 Andrew LOCKLEY Zhifu MI D'Mans COFFMAN 《工程管理前沿:英文版》 2019年第1期38-51,共14页
Geoengineering is a proposed response to anthropogenic global warming (AGW). Conventionally it consists of two strands: Solar Radiation Management (SRM), which is fast-acting, incomplete but inexpensive, and Carbon Di... Geoengineering is a proposed response to anthropogenic global warming (AGW). Conventionally it consists of two strands: Solar Radiation Management (SRM), which is fast-acting, incomplete but inexpensive, and Carbon Dioxide Removal (CDR), which is slower acting, more expensive, and comprehensive. Pairing SRM and CDR offers a contractually complete solution for future emissions if effectively-scaled and coordinated. SRM offsets warming, while CDR takes effect. We suggest coordination using a blockchain, i.e. smart contracts and a distributed ledger. Specifically, we integrate CDR futures with time and volume-matched SRM orders, to address emissions contractually before release. This provides an economically and environmentally proportionate solution to CO2 emissions at the wellhead, with robust contractual transparency, and minimal overhead cost. Our proposal offers a 'polluter pays' implementation of Long & Shepherds SRM 'bridge' concept. This 'polluter geoengineers' approach mandates and verifies emissionslinked payments with minimal friction, delay, or cost. Finally, we compare alternative market designs against this proposal, finding that this proposal offers several advantages. We conclude that blockchain implementation of the 'polluter geoengineers' approach is attractive and feasible for larger wellhead contracts. We also identify a handful of advantages and disadvantages that merit further study. 展开更多
关键词 GEOENGINEERING Solar Radiation MANAGEMENT Carbon Dioxide Removal FUTURES MARKETS smart contracts blockchain
常州市青洋路高架北部延伸线工程总体设计 预览
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作者 宋宇衡 史夕金 《城市道桥与防洪》 2019年第8期1-3,M0004共4页
青洋路高架北部延伸线是常州市“一环八射”快速路网中一条重要的射线快速路,是衔接G42沪宁高速公路青龙互通的一条城市对外交通快速转换的重要通道。以青洋路高架北部延伸线工程总体设计为基础,分析了项目的建设背景、规模、功能定位,... 青洋路高架北部延伸线是常州市“一环八射”快速路网中一条重要的射线快速路,是衔接G42沪宁高速公路青龙互通的一条城市对外交通快速转换的重要通道。以青洋路高架北部延伸线工程总体设计为基础,分析了项目的建设背景、规模、功能定位,并详细介绍了快速路形式、标准横断面、平面总体布置、城市快速路与高速公路衔接设计、桥梁工程及综合管线工程等方面,为其他城市类似工程提供参考。 展开更多
关键词 城市快速路 放射线 功能定位 总体设计 高速公路衔接
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Optimizing neoadjuvant radiotherapy for resectable and borderline resectable pancreatic cancer using protons 预览
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作者 Romaine Charles Nichols Michael Rutenberg 《世界胃肠外科杂志:英文版(电子版)》 2019年第7期303-307,共5页
Approximately 25%of patients diagnosed with pancreatic cancer present with non-metastatic resectable or borderline resectable disease.Unfortunately,the cure rate for these“curable”patients is only in the range of 20... Approximately 25%of patients diagnosed with pancreatic cancer present with non-metastatic resectable or borderline resectable disease.Unfortunately,the cure rate for these“curable”patients is only in the range of 20%.Local-regional failure rates may exceed 50%after margin-negative,node-negative pancreatectomy,but up to 80%of resections are associated with regional lymph node or margin positivity.While systemic drug therapy and chemotherapy may prevent or delay the appearance of distant metastases,it is unlikely to have a significant impact on local-regional disease control.Preoperative radiotherapy would represent a rational intervention to improve local-regional control.The barrier to preoperative radiotherapy is the concern that it could potentially complicate what is already a long and complicated operation.When the radiotherapy is delivered with X-rays(photons),the entire cylinder of the abdomen is irradiated;therefore,an operating surgeon may be reluctant to accept the associated risk of increased toxicity.When preoperative radiotherapy is delivered with protons,however,significant bowel and gastric tissue-sparing is achieved and clinical outcomes indicate that proton therapy does not increase the risk of operative complications nor extend the length of the procedure. 展开更多
关键词 Radiation ONCOLOGY PANCREATIC cancer PROTON therapy
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