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IRS辅助的毫米波MIMO系统多目标波束赋形算法

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北京邮电大学学报 2024年第3期47卷 124-129页

作者：王晓辉许鹏常文慧沈阳航空航天大学电子信息工程学院沈阳110136

针对分布式智能反射面(IRS)辅助的毫米波多输入多输出(MIMO)系统中无法兼顾能量效率和频谱效率的问题,提出一种基于能量效率和频谱效率权衡的多目标优化的主、被动波束赋形算法。首先,利用线性加权法建立能量效率和频谱效率的多目标优... 详细信息

针对分布式智能反射面(IRS)辅助的毫米波多输入多输出(MIMO)系统中无法兼顾能量效率和频谱效率的问题,提出一种基于能量效率和频谱效率权衡的多目标优化的主、被动波束赋形算法。首先,利用线性加权法建立能量效率和频谱效率的多目标优化框架;其次,利用交替优化算法联合优化主动波束赋形和被动波束赋形;最后,利用半正定松弛算法解决非凸的单位模约束问题。仿真实验结果表明,所提算法可以根据实际通信业务灵活调节权衡系数,以实现能量效率与频谱效率之间的均衡。

关键词：毫米波多输入多输出智能反射面波束赋形能量效率频谱效率

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Rapid re-emergence of YMDD mutation of hepatitis B virus with hepatic decompensation after lamivudine retreatment

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World Journal of Gastroenterology 2008年第27期14卷 4416-4419页

作者： So Young Kwon Won Hyeok Choe chang Hong Lee Jong Eun yeon Kwan Soo Byun Department of Internal Medicine Konkuk University School of Medicine Department of Internal Medicine Korea University College of Medicine

Lamivudine has a high rate of antiviral resistance. sequential treatment of anti-hepatitis B virus (HBV) is commonly used for lamivudine resistance. We report 4 cases of patients with rapid redetection of HBV mutants during the lamivudine retreatment. The four patients received lamivudine as an initial treatment of HBV and adefovir and lamivudine as a rescue therapy consecutively. HBV-DNA level, YMDD mutations and adefovir -resistant mutations (RFMP) were tested every 3 mo during the sequential treatment. All the patients showed YMDD mutations during the initial lamivudine therapy. After adefovir therapy for lamivudine resistance, they showed viral breakthrough. Adefovir was switched to lamivudine, however, it did not induce viral suppression at all, rather increased HBV-DNA with rapid reemergence of the YMDD mutations. All the patients had ALT flares, and hepatic decompensation occurred in two patients. After switching to adefovir combined with entecavir or lamivudine for a rescue therapy, the patients had reduction in HBV-DNA and ALT improvement. These cases demonstrated that lamivudine retreatment of patients with preexposed lamivudine resistance leads to rapid reemergence of YMDD mutation with significant viral rebounds and subsequent hepatic decompensation. sequential administration of lamivudine in patients with a prior history of YMDD mutation should be abandoned.

关键词： Hepatitis B Lamivudine Adefovir dipivoxil Mutations

Crystal structure of Arabidopsis thaliana RabA1a

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Journal of Integrative Plant Biology 2019年第2期61卷 93-109页

作者： Ji-Sook Yun Sung Chul Ha Shinae Kim yeon-Gil Kim Hyeran Kim Jeong Ho chang Department of Biology Education Kyungpook National University Beamline Science Division Pohang Accelerator Laboratory 3. Department of Biological Sciences Kangwon National University

RabGTPase is a member of the Ras superfamily of small GTPases, which share a GTP-binding pocket containing highly conserved motifs that promote GTP hydrolysis. In Arabidopsis, the RabA group, which corresponds to the Rabgroup in animals, functions in the recycling of endosomes that control docking and fusion during vesicle transport. However, their molecular mechanisms remain unknown. In this study, we determined the crystal structures of the GDP-bound inactive form and both GppNHp-and GTP-bound active forms of RabA1a, at resolutions of 2.8, 2.6, and 2.6 A?,respectively. A bound sulfate ion in the active site of the GDP-bound structure stabilized Switch Ⅱ by bridging the interaction between a magnesium ion and *** of the two states of RabA1a with Rabproteins revealed clear differences in the Switch Ⅰ and Ⅱ loops. These results suggested that conformational change of the Switch regions of RabA1a, derived by GTP or GDP binding, could maintain subcellular membrane traffic through the specific interaction of effector molecules.

关键词： GDP Crystal structure of Arabidopsis thaliana RabA Figure

Ocular image-based deep learning for predicting refractive error:A systematic review

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Advances in Ophthalmology Practice and Research 2024年第3期4卷 164-172页

作者： Samantha Min Er Yew Yibing Chen Jocelyn Hui Lin Goh David Ziyou Chen Marcus Chun Jin Tan Ching-Yu Cheng Victor Teck chang Koh Yih Chung Tham Department of Ophthalmology Yong Loo Lin School of MedicineNational University of SingaporeSingapore Centre for Innovation and Precision Eye Health Yong Loo Lin School of MedicineNational University of SingaporeSingapore School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore Singapore Eye Research Institute Singapore National Eye CentreSingapore Department of Ophthalmology National University HospitalSingapore Ophthalmology and Visual Sciences(Eye ACP) Duke-NUS Medical SchoolSingapore

ackground:Uncorrected refractive error is a major cause of vision impairment worldwide and its increasing prevalent necessitates effective screening and management ***,deep learning,a subset of Artificial Intelligence,has significantly advanced ophthalmological diagnostics by automating tasks that required extensive clinical *** recent studies have investigated the use of deep learning models for refractive power detection through various imaging techniques,a comprehensive systematic review on this topic is has yet be *** review aims to summarise and evaluate the performance of ocular image-based deep learning models in predicting refractive *** text:We search on three databases(PubMed,Scopus,Web of Science)up till June 2023,focusing on deep learning applications in detecting refractive error from ocular *** included studies that had reported refractive error outcomes,regardless of publication *** systematically extracted and evaluated the continuous outcomes(sphere,se,cylinder)and categorical outcomes(myopia),ground truth measurements,ocular imaging modalities,deep learning models,and performance metrics,adhering to PRISMA *** studies were identified and categorised into three groups:retinal photo-based(n=5),OCT-based(n=1),and external ocular photo-based(n=3).For high myopia prediction,retinal photo-based models achieved AUC between 0.91 and 0.98,sensitivity levels between 85.10%and 97.80%,and specificity levels between 76.40%and 94.50%.For continuous prediction,retinal photo-based models reported MAE ranging from 0.31D to 2.19D,and R^(2) between 0.05 and *** OCT-based model achieved an AUC of 0.79–0.81,sensitivity of 82.30%and 87.20%and specificity of 61.70%–68.90%.For external ocular photo-based models,the AUC ranged from 0.91 to 0.99,sensitivity of 81.13%–84.00%and specificity of 74.00%–86.42%,MAE ranges from 0.07D to 0.18D and accuracy ranges from 81.60%to 96.70%.The reported papers colle

关键词： Deep Learning Artificial Intelligence Refractive Error Retinal images Optical Coherence Tomography Photorefraction Ocular images Prediction

Impact of old age on clinical and angiographic characteristics of coronary artery spasm as assessed by acetylcholine provocation test

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Journal of Geriatric Cardiology 2016年第10期13卷 824-829页

作者： Woong Gil Choi Soo Hyun Kim seung-Woon Rha Kang-Yin CHEN Yong-Jian LI Byoung Geol Choi se yeon Choi Jin Won Kim Eung Ju Kim chang Gyu Park Hong seog seo Dong Joo Oh Department of Internal Medicine School of Medicine Kunkuk University Chungbuk South Korea Cardiovascular Center Korea University Guro Hospital Seoul South Korea Department of Cardiology the Second Hospital of Tianjin Medical University Tianjin China Department of Cardiology Nankai Hospital Tianjin Medical University Tianjin China

Background Smoking and other risk factors have been well known as important factors of variant angina or coronary artery spasm （CAS）. However, clinical features related to age on coronary artery spasm have been rarely evaluated. Methods We evaluated 3155 consecutive patients with insignificant coronary artery lesion. Patients underwent Acetylcholine （Ach） provocation test for induction of CAS. CAS was defined as 〉 70% luminal narrowing of coronary arteries during Ach provocation test. The results of Ach provocation test were compared among age groups; 〈 45 years （Group 1）, 45-54 years （Group 2）, 55-64 years （Group 3）, and 〉_ 65 years （Group 4）. Results Older patients had higher incidence of hypertension, diabetes, but lower incidence rate of current smoking, male sex compared with younger patients. Positive Ach provocation test finding was frequently showed with aging （47.36% vs. 58.3% vs. 62.6% vs. 61.5%; P 〈 0.001）. Multivariate logistic analysis showed that age, male, and myocardial bridge were independent predictors of CAS induced by Ach provocation test. Conclusion Our present study showed that old age was independent predictor for Ach-induced significant coronary artery spasm.

关键词： Acetylcholine Age factor Coronary vasospasm

An herbal formula,CGX,exerts hepatotherapeutic effects on dimethylnitrosamine-induced chronic liver injury model in rats

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World Journal of Gastroenterology 2006年第38期12卷 6142-6148页

作者： Jang-Woo Shin Jin-Young Son se-Mi Oh seung-Hyun Han Jing-Hua Wang Jung-Hyo Cho Chong-Kwan Cho Hwa-seung Yoo yeon-Weol Lee Myong-Min Lee Xiao Ping Hu chang-Gue Son East-West Cancer Center Dunsan Oriental Hospitalof Orientai medical College of Daejeon University 1136 Dunsan-dong Seo-gu Daejeon 302-122 South Korea Department of Oromaxillofacial Infection and Immunity and Dental Research Institute School of Dentistry Seoul National University 28 Yongon-Dong Chongno-Gu Seoul 110-749 South Korea

AIM： To evaluate the therapeutic effect of Chunggan extract （CGX）, a modified traditional Chinese hepatotherapeutic herbal, on the dimethylnitrosamine （DMN）-induced chronic liver injury model in rats. METHODS： Liver injuries were induced in Wistar rats by injection of DMN （ip, 10 mg/mL per kg） for 3 consecutive days per week for 4 wk. The rats were administered with CGX Coo, 100 or 200 mg/kg per day） or distilled water as a control daily for 4 wk starting from the 15^th d of the DMN treatment. Biochemical parameters （serum albumin, bilirubin, ALP, AST and ALT）, lipid peroxides, hydroxyproline, as well as histological changes in liver tissues were analyzed. In addition, gene expression of TNF-α, TGF-β, TIMP-1, TIMP-2, PDGF-β, and MMP-2, all of which are known to be associated with liver fibrosis, were analyzed using real-time PCR. RESULTS： CGX administration restored the spleen weight to normal alter having been increased by DMN treatment. Biochemical analysis of the serum demonstrated that CGX significantly decreased the serum level of ALP （P 〈 0.05）, ALT （P 〈 0.02）, and AST （P 〈 0.02） that had been elevated by DMN treatment. CGX administration moderately lowered lipid peroxide production and markedly lowered hydroxyproline generation caused by DMN treatment in accordance with histopathological examination. DMN treatment induced a highly upregulated expression of TNF-α, TGF-β,TIMP-1, TIMP-2, PDGF-β, and MMP-2. Of these, the gene expression encoding PDGF-β and MMP-2 was still further enhanced 2 wk after secession of the 4-wk DMN treatment, and was remarkably ameliorated by CGX administration. CONCLUSION： CGX exhibits hepatotherapeutic properties against chronic hepatocellular destruction and consequential liver fibrosis.

关键词： Dimethylnitrosamine Hepatotherapeutic Herbal medicine PDGF-β Chunggan extract

Mitochondria-targeting drug conjugates for cytotoxic, anti-oxidizing and sensing purposes:current strategies and future perspectives

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Acta Pharmaceutica Sinica B 2018年第6期8卷 862-880页

作者： Gantumur Battogtokh yeon Su Choi Dong seop Kang Sang Jun Park Min Suk Shim Kang Moo Huh Yong-yeon Cho Joo Young Lee Hye Suk Lee Han chang Kang Department of Pharmacy Integrated Research Institute of Pharmaceutical Sciences and BK21 PLUS Team for Creative Leader Program for Pharmacomics-based Future Pharmacy College of Pharmacy The Catholic University of Korea Division of Bioengineering Incheon National University Department of Polymer Science and Engineering Chungnam National University

mitochondrial-targeting moieties to anticancer drugs, antioxidants and sensor molecules. Among them, the most widely applied mitochondrial targeting moiety is triphenylphosphonium(TPP), which is a delocalized cationic lipid that readily accumulates and penetrates through the mitochondrial membrane due to the highly negative mitochondrial membrane potential. Other moieties, including short peptides,dequalinium, guanidine, rhodamine, and F16, are also known to be promising mitochondrial targeting agents. Direct conjugation of mitochondrial targeting moieties to anticancer drugs, antioxidants and sensors results in increased cytotoxicity, anti-oxidizing activity and sensing activity, respectively,compared with their non-targeting counterparts, especially in drug-resistant cells. Although many mitochondria-targeted anticancer drug conjugates have been investigated in vitro and in vivo, further clinical studies are still needed. On the other hand, several mitochondria-targeting antioxidants have been analyzed in clinical phases I, II and III trials, and one conjugate has been approved for treating eye disease in Russia. There are numerous ongoing studies of mitochondria-targeted sensors.

关键词： Anticancer agents Antioxidants Direct conjugation Mitochondria-targeting sensing agents

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Clinical characteristics of patients in their forties who underwent surgical resection for colorectal cancer in Korea

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World Journal of Gastroenterology 2021年第25期27卷 3901-3912页

作者： chang Sin Lee se-Jin Baek Jung-Myun Kwak Jin Kim seon-Hahn Kim Department of Surgery Korea University College of MedicineSeoul 02841South Korea

BACKGROUND The proportion of young patients with colorectal cancer(CRC),especially in their 40s,is increasing *** To confirm the clinical characteristics of such patients,we planned a study comparing them to patients in their 30s and *** Patients undergoing primary resection for CRC,patients in their 30s,40s and 50s were included in the *** and tumor characteristics,and perioperative and oncologic outcomes were *** Most clinical characteristics of 451(10.5%)patients in their 40s were more similar to those of patients in their 30s than those in their *** pathology data,there were more metastatic lesions(30s vs 40s vs 50s;17.5%vs 21.1%vs 14.9%,P=0.012)in patients in their *** was a trend toward less frequent K-ras mutations among patients in their 40s(48.5%vs 33.3%vs 44.5%,P=0.064).The proportion of patients receiving postoperative chemotherapy was also significantly greater among patients in their 40s(58.3%vs 63.9%vs 56.3%,P=0.032).Five-year overall survival(OS)and disease-free survival(DFS)did not differ between the three groups(5-year OS,92.2%vs 89.8%vs 92.2%,P=0.804;5-year total DFS,98.6%vs 95.7%vs 96.1%,P=0.754;5-year local DFS,98.6%vs 94.3%vs 94.9%,P=0.579;5-year systemic DFS,86.4%vs 87.9%vs 86.4%,P=0.908).CONCLUSION Patients with CRC in their 40s showed significantly more numerous metastatic *** oncologic outcome of stage 1-3 patients in their 40s was not inferior compared to that of those in their 30s and 50s.

关键词： Colorectal neoplasm Young age Hereditary cancer Sporadic cancer Screening

β-Arrestin 2 suppresses the activation of YAP by promoting LATS kinase activity

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Genes & Diseases 2023年第2期10卷 348-351页

作者： Minsuh Kim Ji Min Kim Eun Jeong Cho chang Ohk Sung Joon Kim se Jin Jang Asan Institute for Life Sciences Asan Medical CenterSeoul 05505Republic of Korea University of Ulsan College of Medicine Seoul 05505Republic of Korea Department of Pathology Asan Medical CenterSeoul 05505Republic of Korea Graduate School of Medical Science and Engineering KAISTDaejeon 34141Republic of Korea OncoClew Life Science Co. LtdSeoul 05505Republic of Korea

Dysregulation of the Hippo pathway has been frequently identified in various human cancers. The Hippo pathway is a highly complex pathway involving multiple types of proteins, and the activation of YAP by LATS kinase is the final effector step in the transcription process. In this study, we linked the roles of the multifunctional adapter proteins β-arrestins (β-arrestin 1 and 2) in cooperation with other signaling pathways such as GPCR and Wnt to essential cellular functions involved in carcinogenesis, including the regulation of cell proliferation, migration, and differentiation as well as stem cell properties.1 Although β-arrestin 1 and 2 have high structural similarities, they have different roles in carcinogenesis as β-arrestin 1 aids cancer cell survival and metastasis2 and β-arrestin 2 inhibits tumor growth.1 In the Hippo signaling pathway, β-arrestins function as scaffold proteins that mediate the phosphorylation of key molecules, and their association with human cancers is a major research topic. In this study, we demonstrated that β-arrestin 2 inhibits YAP activation through the formation of the β-arrestin 2-LATS-YAP trimeric complex, which results in the promotion of the kinase activity of LATS in cancer cell lines and patient-derived colon cancer organoids.

关键词： cancer carcinogenesis activation