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Low-dose CT for lung cancer screening: opportunities and challenges

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《医学前沿（英文）》 2018年 第12卷 第1期   页码 116-121 doi: 10.1007/s11684-017-0600-1

摘要：

Lung cancer is among the most frequently diagnosed cancers worldwide and the leading cause of cancer death in both males and females. Screening for lung cancer coupled with earlier intervention has long been studied as an approach to mortality reduction. However, minimal progress was achieved until recently, when low-dose spiral computed tomography (LDCT) screening demonstrated a 20% reduction in mortality from lung cancer in a randomized controlled trial (RCT), the National Lung Screening Trial, from the United States. On the basis of this finding, LDCT has been recommended for lung cancer screening in high-risk populations by several clinical guidelines. However, results from the following independent RCTs in Europe failed to show consistent conclusions. In addition, intractable problems gradually emerged with the progress of LDCT screening. This paper summarizes and discusses the main observations and challenges of LDCT screening for lung cancer. Before spreading implementation of LDCT screening, challenges, including high false-positive rates, overdiagnosis, enormous costs, and radiation risk, must be addressed. Complementary biomarkers and technical improvement are expected in the field of lung cancer screening in the near future.

关键词： lung cancer     low-dose computerized tomography     early detection     opportunities     challenges    

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结合全变分最小化和稀疏字典学习后处理的低剂量CT重建 Article

Yong DING, Tuo HU

《信息与电子工程前沿（英文）》 2017年 第18卷 第12期   页码 2001-2008 doi: 10.1631/FITEE.1700287

摘要： 随着CT（computed tomography）中过量辐射剂量带来的健康风险日渐引发人们的担忧，低剂量CT得到了大量的关注。

关键词： 低剂量CT；CT成像；全变分；稀疏字典学习    

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Comparison of exogenous degrader-enhanced bioremediation with low-dose persulfate oxidation for polycyclic

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1733-x

摘要： Polycyclic aromatic hydrocarbon (PAH)-contaminated soils are usually complex and characterized by a lack of nutrition and soil salinization, resulting in difficulties in soil remediation. In this study, bioaugmentation with a PAH-degrading Bacillus PheN7 (BA) and low-dose persulfate oxidation (PS), along with natural biodegradation, were utilized to remediate alkaline PAH-contaminated soil. The soil used in the study had a pH of 9.35, and the total PAH content was 568.8 ± 31.0 mg/kg dry soil. After 42 d of remediation, the degradation efficiency of PAHs was 96.72% and 93.88% using persulfate oxidation and bioaugmentation, respectively, whereas 38.66% of PAHs were degraded in natural attenuation (NA). Bacillus was the dominant genera throughout the process of bioremediation with the relative abundance of 79.3% on day 42 in the BA system, whereas, Alcanivorax was enriched and became the dominant genera in PS systems. In the meantime, PAH degradation genes were detected with remarkably higher level in the BA system than in PS system during the remediation. In addition to the degradation of contaminants, persulfate oxidation promotes microbial bioremediation efficiency mainly by lowering the pH to neutral and increasing the active phosphorus content in the soil. Microbial species and ecological niches were less reduced in the PS system than in the BA system. Collectively, persulfate oxidation had a better impact on the soil microbiome and is more suitable for long-term soil health than bioaugmentation through PheN7 addition.

关键词： Bioaugmentation     Low-dose persulfate oxidation     Polycyclic aromatic hydrocarbon     Remediation    

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Venetoclax and low-dose cytarabine induced complete remission in a patient with high-risk acute myeloid

Bingshan Liu, Roshni Narurkar, Madhura Hanmantgad, Wahib Zafar, Yongping Song, Delong Liu

《医学前沿（英文）》 2018年 第12卷 第5期   页码 593-599 doi: 10.1007/s11684-018-0635-y

摘要：

Conventional combination therapies have not resulted in considerable progress in the treatment of acute myeloid leukemia (AML). Elderly patients with AML and poor risk factors have grave prognosis. Midostaurin has been recently approved for the treatment of FLT-3-mutated AML. Venetoclax, a BCL-2 inhibitor, has been approved for the treatment of relapsed and/or refractory chronic lymphoid leukemia. Clinical trials on applying venetoclax in combination with cytarabine and other agents to treat various hematological malignancies are currently underway. Here, we present a case of a male patient with poor performance status and who developed AML following allogeneic hematopoietic stem cell transplant for high-risk myelodysplasia. The patient with high risk AML achieved complete response to the combined treatment regimen of low-dose cytarabine and venetoclax. Furthermore, we reviewed current clinical trials on the use of venetoclax for hematological malignancies.

关键词： venetoclax     cytarabine     AML     leukemia    

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Fatigue of asphalt binder, mastic and mixture at low temperature

Dong WANG, Linbing WANG, Guoqing ZHOU

《结构与土木工程前沿（英文）》 2012年 第6卷 第2期   页码 166-175 doi: 10.1007/s11709-012-0157-7

摘要： The fatigue damage is one of the most common distresses observed on the asphalt concrete pavement. To thoroughly understand the fatigue of asphalt concrete, the behaviors of the major components of asphalt concrete under cyclic loading are investigated respectively in this study. A new experiment method is developed to evaluate the performances of asphalt binder, mastic and fine aggregates mixture under cyclic tensile loading. The fatigue test results of asphalt binder show that the fatigue performance of asphalt binder is closely related with loading magnitude, temperature and loading rate. Mastic specimens with different filler content are tested and the results indicate that mastic specimens with 30% filler content show better fatigue resistance and higher permanent strain. The micro-structure analysis of mastic and mixture indicates that the fatigue resistance is closely related with the air void content of specimen. 3D digital specimens are developed to model the fatigue of the asphalt binder, mastic and mixture specimens based on the finite element method (FEM). Fatigue damage of asphalt concrete is simplified by a damage model. With proper selection of damage parameters, the simulation results agree well with laboratory test results and can be used as a basis for future fatigue research.

关键词： fatigue     asphalt mixture     asphalt binder     mastic     finite element method (FEM)     X-ray tomography    

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Cancer and the environment: Filling knowledge gaps together

Linda S. BIRNBAUM PhD, DABT, ATS,

《医学前沿（英文）》 2010年 第4卷 第2期   页码 131-133 doi: 10.1007/s11684-010-0044-3

摘要： When considering disease etiology, we need to view the role of the environment along the continuum from health to disease for individuals because we know that there are complex interactions between genes, their molecular expression, and environmental factors over a person’s lifetime. We clearly have huge gaps in our knowledge along this continuum, and these gaps are natural opportunities for research. There are many factors to consider as we assess the relationship between environmental exposures over a lifetime. One factor is persistence of chemicals that “live” beyond their initial intended use. Another factor is the fact that “inert ingredients” are not really inert. “Low dose” is also another consideration. We need to understand the biological effect of low dose exposure and we should clearly define what they mean by low dose research. For example, are we measuring the administered dose, or the internal/circulating dose? There are new types of toxicity as well. For example, endocrine disruptors and engineered nanomaterials are significant classes of materials deserving significant research. Timing of exposure is a significant feature in characterizing toxicity. Environmental exposures can have a greater impact in early or later life-stages. Finally, mixtures of chemicals are an important consideration. Humans are always exposed to multiple chemicals. In short, we must remember that there is no such thing as “not exposed.” Everyone has been exposed to many and various environmental agents.

关键词： environment     genes     environmental exposure     environmental agent     persistence     chemicals     inert ingredients     low dose    

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Estimation of the minimum effective dose of tramadol for postoperative analgesia in infants using the

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《医学前沿（英文）》 2012年 第6卷 第3期   页码 288-295 doi: 10.1007/s11684-012-0208-4

摘要：

Tramadol is a potent analgesic. However, the analgesia efficacy of tramadol, particularly its minimum effective dose (MED), is not clear. The aim of this study is to find MED of tramadol for postoperative analgesia in infants. The continual reassessment method (CRM) was performed to find MED. Infants undergoing surgeries were included in the 3 phases of this series. In each phase, 24 participants were allocated a different tramadol dose. Pain intensity was measured by face, legs, activity, cry, consolability (FLACC) measurement at 3-hour intervals. Tramadol was considered ineffective if the FLACC score was higher than 4 in 10 at anytime. In phase 1, seven dose levels were used within the range 0.1–0.4 mg?kg-1·h-1. Phase 1 was insufficient to identify the MED, and we increased the dose to 0.4–0.8 mg?kg-1·h-1 in phase 2. Phase 2 was insufficient to identify the MED. In phase 3, local anesthetic wound infiltration was introduced, and the tramadol dose levels tested were the same as in phase 1. The successful analgesia probability of tramadol 0.4 mg?kg-1?h-1 was 82.1% (95% CI, 0.742–0.925) in phase 1. In phase 2, it was 84.7% (95% CI, 0.789–0.991) with the dose 0.8 mg?kg-1?h-1. Phase 1 and phase 2 were insufficient to identify the MED. In phase 3, the successful analgesia probability for dose 0.35 mg?kg-1?h-1was 96.7% (95% CI, 0.853–0.997).We have demonstrated that tramadol provides insufficient analgesia for surgeries considered to cause moderate-to-severe postoperative pain in infants if used as the sole analgesic, and that local anesthetic wound infiltration enhances the efficacy of tramadol.

关键词： tramadol     minimum effective dose     postoperative analgesia     infants     continual reassessment method    

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Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

《医学前沿（英文）》 2011年 第5卷 第3期   页码 254-270 doi: 10.1007/s11684-011-0153-7

摘要： Multislice computed tomography (CT) has been widely used in clinical practice for the diagnosis of cardiovascular disease due to its reduced invasiveness and high spatial and temporal resolution. As a reliable alternative to conventional angiography, multislice CT angiography has been recognized as the method of choice for detecting and diagnosing head and neck vascular disease, abdominal aortic aneurysm, aortic dissection, and pulmonary embolism. In patients with suspected coronary artery disease, although invasive coronary angiography still remains as the gold standard technique, multislice CT angiography demonstrates high diagnostic accuracy; in selected patients, it is considered as the first-line technique. The imaging diagnosis of cardiovascular disease is based on a combination of two-dimensional (2D) and three-dimensional (3D) visualization tools to enhance the diagnostic value. This is facilitated by reconstructed visualizations which provide additional information about the extent of the disease, an accurate assessment of the spatial relationship between normal structures and pathological changes, and pre-operative planning and post-procedure follow-up. The aim of the present article is to present an overview of the diagnostic performance of various 2D and 3D CT visualizations in cardiovascular disease, including multiplanar reformation, maximum intensity projection, volume rendering, and virtual intravascular endoscopy. The recognition of the potential value of these visualizations will assist clinicians in efficiently using the multislice CT imaging modality for the diagnostic management of patients with cardiovascular disease.

关键词： cardiovascular disease     multislice computed tomography     three-dimensional reconstruction     diagnosis     visualization    

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Early assessment of the safety and immunogenicity of a third dose (booster) of COVID-19 immunization

《医学前沿（英文）》 2022年 第16卷 第1期   页码 93-101 doi: 10.1007/s11684-021-0914-x

摘要： Inducing durable and effective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via vaccination is essential to combat the current pandemic of coronavirus disease 2019 (COVID-19). It has been noticed that the strength of anti-COVID-19 vaccination-induced immunity fades over time, which calls for an additional vaccination regime, as known as booster immunization, to restore immunity among previously vaccinated populations. Here we report a pilot open-label trial of a third dose of BBIBP-CorV, an inactivated SARS-CoV-2 vaccine (Vero cell), on 136 participants aged between 18 to 63 years. Safety and immunogenicity in terms of neutralizing antibody titers and cytokine/chemokine responses were analyzed as the main endpoint until day 28. While systemic reactogenicity was either absent or mild, SARS-CoV-2-specific neutralizing antibody titers rapidly arose in all participants within 4 weeks, surpassing the peak antibody titers elicited by the initial two-dose immunization regime. Broad increases of cellular immunity-associated cytokines and chemokines were also detected in the majority of participants after the third vaccination. Furthermore, in an exploratory study, a newly developed recombinant protein vaccine, NVSI-06-08 (CHO Cells), was found to be safe and even more effective than BBIBP-CorV in eliciting humoral immune responses in BBIBP-CorV-primed individuals. Together, these results indicate that a third immunization schedule with either homologous or heterologous vaccine showed favorable safety profiles and restored potent SARS-CoV-2-specific immunity, providing support for further trials of booster vaccination in larger populations.

关键词： COVID-19     SARS-CoV-2     vaccine     immunization     booster immunization    

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Determining casting defects in near-net shape casting aluminum parts by computed tomography

Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER

《机械工程前沿（英文）》 2018年 第13卷 第1期   页码 48-52 doi: 10.1007/s11465-018-0493-y

摘要：

Three types of near-net shape casting aluminum parts were investigated by computed tomography to determine casting defects and evaluate quality. The first, second, and third parts were produced by low-pressure die casting (Al-12Si-0.8Cu-0.5Fe-0.9Mg-0.7Ni-0.2Zn alloy), die casting (A356, Al-7Si-0.3Mg), and semi-solid casting (A356, Al-7Si-0.3Mg), respectively. Unlike die casting (second part), low-pressure die casting (first part) significantly reduced the formation of casting defects (i.e., porosity) due to its smooth filling and solidification under pressure. No significant casting defect was observed in the third part, and this absence of defects indicates that semi-solid casting could produce high-quality near-net shape casting aluminum parts. Moreover, casting defects were mostly distributed along the eutectic grain boundaries. This finding reveals that refinement of eutectic grains is necessary to optimize the distribution of casting defects and reduce their size. This investigation demonstrated that computed tomography is an efficient method to determine casting defects in near-net shape casting aluminum parts.

关键词： near-net shape casting     aluminum parts     casting defects     low pressure die casting     die casting     semi-solid casting     computed tomography    

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An investigation on patient dose in screen-film diagnostic radiology in Lhasa City, Xizang Autonomous

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《医学前沿（英文）》 2013年 第7卷 第4期   页码 506-509 doi: 10.1007/s11684-013-0294-y

摘要：

This study aimed to investigate patient dose in diagnostic screen-film radiographic examinations in the city of Lhasa, China. Seven out of the twenty-six hospitals registered with the Lhasa Health Bureau were included in the investigation. The entrance surface air Kerma (ESAK) of seven conventional screen-film radiology X-ray equipment in these hospitals was measured with a QA dosimeter in September 2012. The X-ray examinations were divided into three categories: PA (posterior-anterior) chest, upper/lower limb, and AP (anterior-posterior) lumbar spine. For each category, ESAKs were calculated and analyzed. The mean ESAK was 0.6 mGy for PA chest, 0.3 mGy for upper/lower limb, and 1.8 mGy for AP lumbar spine. In addition, the mean ESAK value recorded for PA chest X-ray examinations exceeded the corresponding value recommended by the International Atomic Energy Agency (0.4 mGy).

关键词： radiation dosage     radiology     radiation protection     radiography/statistics & numerical data    

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of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitance tomography

CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan

《机械工程前沿（英文）》 2006年 第1卷 第2期   页码 242-247 doi: 10.1007/s11465-006-0008-0

摘要： Sensor sensitivity field in electrical capacitance tomography is affected by the distribution of multiphase medium, which is the peculiarity of soft field. This brings great difficulty for image reconstruction. To improve the quality of image reconstruction, it is important to analyze the distribution of the sensitivity field. In this article, using the finite element method, we expound a kind of novel plotting pattern to field, which is the distribution of sensitivity field through computer simulation. From experiments and results of sensitivity field analysis, a novel method of image reconstruction based on genetic algorithms is presented. The finite element model is correct and simulation result is fine by adopting unequal interval plotting patterns. At the same time, the result of image reconstruction has high precision.

关键词： multiphase     unequal interval     capacitance tomography     pattern     sensitivity    

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珊瑚岛礁环境噪声成像 Article

夏少红, 张昌榕, 曹敬贺

《工程（英文）》 2023年 第25卷 第6期   页码 182-193 doi: 10.1016/j.eng.2021.09.022

摘要：

As valuable land in the ocean, coral islands are not only important bases for making use of marine resources and protecting marine rights and interests, but also important for breakthrough research in many fields of earth science. Hence, the economical and efficient determination of the underground structure of coral islands has become significant in coral island engineering geology, but remains challenging for traditional marine geophysical prospecting and drilling methods. While ambient noise tomography with dense arrays has been widely used in continental regions, its applicability to coral islands remains undetermined. In this study, based on the data recorded by a dense array on an isolated coral island in the South China Sea, we analyzed the ambient noise characteristics and obtained a 3D subsurface structure of the coral island using ambient noise tomography. We made the following findings: ① The ambient noise frequencies can be roughly categorized into three levels: < 1, 1–5, and > 5 Hz. The spectral characteristics of the noise below 5 Hz were consistent at different stations, but there were significant differences in the characteristics of the noise above 5 Hz. ② For ambient noise frequencies below 5 Hz, cross-correlation functions with high quality could be obtained with only 24 h of waveform data. However, it was difficult to extract meaningful cross-correlation functions for ambient noise frequencies above 5 Hz. ③ The S-wave velocity in the coral island was higher toward the sea and lower toward the lagoon, which was consistent with the high degree of cementation of the outer reef flat stratum on the seaward side. ④ There were two low-velocity horizons at 25–75 and 200–300 m, which were in good agreement with the high-porosity horizons that were revealed by drilling core samples, reflecting the weathering history of the reef. Our research demonstrates that ambient noise tomography is a potentially economical, efficient, and environmentally friendly method for the geological prospecting of coral reefs.

关键词： Coral island     Ambient noise tomography     Engineering geology     South China Sea    

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Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR

Guangrong Sun, Chuanyi Zhang, Wei Li, Limei Yuan, Shilong He, Liping Wang

《环境科学与工程前沿（英文）》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1085-8

摘要： To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosing in a University of Cape Town Membrane Bioreactor (UCT-MBR) was investigated, in terms of the nutrients removal performance, sludge characteristics and membrane fouling. The results indicated that the addition of aluminum sulfate into the aerobic reactor continuously had significantly enhanced phosphorus removal. Moreover, COD, NH -N and TN removal were not affected and effluent all met the first level A criteria of GB18918-2002. In addition, the addition of aluminum sulfate had improved the sludge activity slightly and reduced trans-membrane pressure (TMP) increase rate from 1.13 KPa/d to 0.57 KPa/d effectively. The membrane fouling was alleviated attributed to the increased average particle sizes and the decreased accumulation of the small sludge particles on membrane surface. Furthermore, the decline of extracellular polymeric substance (EPS) concentration in mixed sludge liquid decreased its accumulation on membrane surface, resulting in the mitigation of membrane fouling directly.

关键词： University of Cape Town Bioreactor (UCT-MBR)     enhanced nutrients removal     aluminum sulfate     sludge activity     membrane fouling    

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radiohormonal therapy for oligo-metastatic prostate cancer: safety and efficacy outcomes from an open-label, dose-escalation

《医学前沿（英文）》 2023年 第17卷 第2期   页码 231-239 doi: 10.1007/s11684-022-0939-9

摘要： To evaluate the safety and efficacy of neoadjuvant radiohormonal therapy for oligometastatic prostate cancer (OMPC), we conducted a 3 + 3 dose escalation, prospective, phase I/II, single-arm clinical trial (CHiCTR1900025743), in which long-term neoadjuvant androgen deprivation was adopted 1 month before radiotherapy, comprising intensity modulated radiotherapy to the pelvis, and stereotactic body radiation therapy to all extra-pelvic bone metastases for 4‒7 weeks, at 39.6, 45, 50.4, and 54 Gy. Robotic-assisted radical prostatectomy was performed after 5‒14 weeks. The primary outcome was treatment-related toxicities and adverse events; secondary outcomes were radiological treatment response, positive surgical margin (pSM), postoperative prostate-specific antigen (PSA), pathological down-grading and tumor regression grade, and survival parameters. Twelve patients were recruited from March 2019 to February 2020, aging 66.2 years in average (range, 52‒80). Median baseline PSA was 62.0 ng/mL. All underwent RARP successfully without open conversions. Ten patients recorded pathological tumor down-staging (83.3%), and 5 (41.7%) with cN1 recorded negative regional lymph nodes on final pathology. 66.7% (8/12) recorded tumor regression grading (TRG) –I and 25% (3/12) recorded TRG-II. Median follow-up was 16.5 months. Mean radiological progression-free survival (RPFS) was 21.3 months, with 2-year RPFS of 83.3%. In all, neoadjuvant radiohormonal therapy is well tolerated for oligometastatic prostate cancer.

关键词： neoadjuvant     radiotherapy     oligometastatic     prostate cancer     radical prostatectomy    

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标题 作者 时间 类型 操作

Low-dose CT for lung cancer screening: opportunities and challenges

null

期刊论文

结合全变分最小化和稀疏字典学习后处理的低剂量CT重建

Yong DING, Tuo HU

期刊论文

Comparison of exogenous degrader-enhanced bioremediation with low-dose persulfate oxidation for polycyclic

期刊论文

Venetoclax and low-dose cytarabine induced complete remission in a patient with high-risk acute myeloid

Bingshan Liu, Roshni Narurkar, Madhura Hanmantgad, Wahib Zafar, Yongping Song, Delong Liu

期刊论文

Fatigue of asphalt binder, mastic and mixture at low temperature

Dong WANG, Linbing WANG, Guoqing ZHOU

期刊论文

Cancer and the environment: Filling knowledge gaps together

Linda S. BIRNBAUM PhD, DABT, ATS,

期刊论文

Estimation of the minimum effective dose of tramadol for postoperative analgesia in infants using the

null

期刊论文

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

期刊论文

Early assessment of the safety and immunogenicity of a third dose (booster) of COVID-19 immunization

期刊论文

Determining casting defects in near-net shape casting aluminum parts by computed tomography

Jiehua LI, Bernd OBERDORFER, Daniel HABE, Peter SCHUMACHER

期刊论文

An investigation on patient dose in screen-film diagnostic radiology in Lhasa City, Xizang Autonomous

null

期刊论文

of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitance tomography

CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan

期刊论文

珊瑚岛礁环境噪声成像

夏少红, 张昌榕, 曹敬贺

期刊论文

Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR

Guangrong Sun, Chuanyi Zhang, Wei Li, Limei Yuan, Shilong He, Liping Wang

期刊论文

radiohormonal therapy for oligo-metastatic prostate cancer: safety and efficacy outcomes from an open-label, dose-escalation

期刊论文