资源类型

期刊论文 92

年份

2023 7

2022 8

2021 6

2020 8

2019 7

2018 7

2017 3

2016 2

2015 3

2014 4

2013 4

2012 6

2011 4

2010 4

2009 2

2008 6

2007 3

2006 2

2001 1

2000 2

展开 ︾

关键词

Anderson 模型 1

BNCT医院中子照射器 1

CO2捕集 1

U251细胞 1

三点弯曲梁 1

不利荷载 1

中医 1

中子和γ吸收剂量率 1

中子能谱 1

中子通量密度 1

中药剂型 1

二次调节 1

交通荷载 1

交通量 1

亲CO2分离膜 1

人参皂苷CK 1

低剂量CT;CT成像;全变分;稀疏字典学习 1

侵彻深度 1

内爆炸荷载 1

展开 ︾

检索范围:

排序: 展示方式:

Clinical significance of human papilloma virus infection in the cervical lesions

Shuang LI, Yu-Han MENG, Hu TING, Jian SHEN, Ding MA

《医学前沿(英文)》 2010年 第4卷 第3期   页码 264-270 doi: 10.1007/s11684-010-0094-6

摘要: Cervical lesions have been regarded as the common and frequently occurring diseases in China. Recently, the morbidity and youth tendency of cervical cancer have gradually increased. Cervical cancer, related with human papilloma virus (HPV) infection, has been one of the severest diseases threatening health and life of women, and is an infectious disease. The universality of HPV infection in the reproductive tract should not be ignored. The well-known risk factors of HPV infection in cervical lesions consist of high-risk sexual behaviors, immunosuppression, age, contraceptive methods, the concurrent infection of other sexually transmitted diseases, etc. The variation of cervical lesions induced by HPV infection is involved in the continuous pathological process, including the subclinical, latent, and persistent infection of high risk (HR)-HPV, chronic cervicitis with abnormal results of cytological examination, cervical intraepithelial neoplasia (CIN), and cervical cancer. The outcome of patients with HPV infection is influenced by many factors, such as HPV subtype dominance, persistent HPV infection, HPV loading dose, and multiple HPV infection. Controlling HR-HPV persistent infection should be an important strategy for reducing cervical lesions.

关键词: cervical lesion     high risk-human papilloma virus     persistent infection     loading dose     cervical intraepithelial neoplasia     cervical cancer    

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

null

《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    

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

null

《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    

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    

enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial loading

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要: Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词: damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

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    

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

null

《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    

Reconsideration on the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

《环境科学与工程前沿(英文)》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1135-2

摘要:

Effect of nitrogen on mixed culture PHA production was reconsidered.

Enrichment history of PHA accumulating culture was discussed.

Higher PHA content and biomass growth were achieved in presence of nitrogen.

Enrichment strategy toward higher PHA accumulation was investigated.

Microbial community succession in PHA accumulation phase was investigated.

关键词: Polyhydroxyalkanoate (PHA)     Organic loading rate     Nitrogen content     Biomass growth     Enrichment history    

Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1595-7

摘要:

● Mechanical behavior of MBT waste affected by loading rate was investigated.

关键词: Mechanically and biologically treated waste     Landfill     Triaxial test     Loading rate     Axial strain     Shear strength parameter    

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    

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    

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    

Axisymmetric loading on nanoscale multilayered media

《结构与土木工程前沿(英文)》 2023年 第17卷 第1期   页码 152-164 doi: 10.1007/s11709-022-0895-0

摘要: Multilayered nanoscale structures are used in several applications. Because the effect of surface energy becomes nontrivial at such a small scale, a modified continuum theory is required to accurately predict their mechanical behaviors. A Gurtin–Murdoch continuum model of surface elasticity is implemented to establish a computational scheme for investigating an elastic multilayered system under axisymmetric loads with the incorporation of surface/interface energy. Each layer stiffness matrix is derived based on the general solutions of stresses and displacements obtained in the form of the Hankel integral transform. Numerical solutions to the global equation, which are formulated based on the continuity conditions of tractions and displacements across interfaces between layers, yield the displacements at each layer interface and on the top surface of the multilayered medium. The numerical solutions indicate that the elastic responses of multilayered structures are affected significantly by the surface material properties of both the top surface and interfaces, and that they become size dependent. In addition, the indentation problem of a multilayered nanoscale elastic medium under a rigid frictionless cylindrical punch is investigated to demonstrate the application of the proposed solution scheme.

关键词: functionally graded layer     Gurtin–Murdoch surface elasticity     multilayered medium     size dependency     stiffness matrix    

Data-driven approach to solve vertical drain under time-dependent loading

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 696-711 doi: 10.1007/s11709-021-0727-7

摘要: Currently, the vertical drain consolidation problem is solved by numerous analytical solutions, such as time-dependent solutions and linear or parabolic radial drainage in the smear zone, and no artificial intelligence (AI) approach has been applied. Thus, in this study, a new hybrid model based on deep neural networks (DNNs), particle swarm optimization (PSO), and genetic algorithms (GAs) is proposed to solve this problem. The DNN can effectively simulate any sophisticated equation, and the PSO and GA can optimize the selected DNN and improve the performance of the prediction model. In the present study, analytical solutions to vertical drains in the literature are incorporated into the DNN–PSO and DNN–GA prediction models with three different radial drainage patterns in the smear zone under time-dependent loading. The verification performed with analytical solutions and measurements from three full-scale embankment tests revealed promising applications of the proposed approach.

关键词: vertical drain     artificial neural network     time-dependent loading     deep learning network     genetic algorithm     particle swarm optimization    

Comparison and harmonization of building wind loading codes among the Asia-Pacific Economies

Yaojun GE, Shuyang CAO, Xinyang JIN

《结构与土木工程前沿(英文)》 2013年 第7卷 第4期   页码 402-410 doi: 10.1007/s11709-013-0230-x

摘要: This paper reviews wind loading codes and standards in the Asia-Pacific Region, in particular in the 15 countries and areas. A general description of wind loading model is given as a famous wind loading chain described by four variables including velocity pressure, exposure factor, pressure coefficient, and gust response factor. Through the APEC-WW Workshops and the extensive calculations for three examples of low, medium and high rise buildings, these four important variables of wind loads are evaluated and compared with statistical parameters, mean values and coefficients of variation. The main results of the comparison show some differences among the 15 economies, and the reasons and further incorporation are discussed and suggested.

关键词: wind loading     codification     velocity pressure     exposure factor     pressure coefficient     gust response factor    

标题 作者 时间 类型 操作

Clinical significance of human papilloma virus infection in the cervical lesions

Shuang LI, Yu-Han MENG, Hu TING, Jian SHEN, Ding MA

期刊论文

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

null

期刊论文

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

null

期刊论文

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

期刊论文

enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial loading

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

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

期刊论文

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

null

期刊论文

Reconsideration on the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

期刊论文

Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

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

Cancer and the environment: Filling knowledge gaps together

Linda S. BIRNBAUM PhD, DABT, ATS,

期刊论文

Axisymmetric loading on nanoscale multilayered media

期刊论文

Data-driven approach to solve vertical drain under time-dependent loading

期刊论文

Comparison and harmonization of building wind loading codes among the Asia-Pacific Economies

Yaojun GE, Shuyang CAO, Xinyang JIN

期刊论文