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miRNA对褐飞虱鞘脂质代谢基因表达的影响及沉默NlSPT1和Nl SMase4的small RNA分析 被引量:1
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作者 王妮 施哲逸 +4 位作者 尤元政 张超 周文武 周瀛 祝增荣 《中国农业科学》 CAS CSCD 北大核心 2024年第20期4022-4034,共13页
【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interfere... 【背景】鞘脂质是第二大类膜脂,作为信号转导物质参与细胞生长发育、繁殖及凋亡等过程。鞘脂质代谢酶调控鞘脂质代谢以维持生物体内代谢的稳态。【目的】以重要水稻害虫褐飞虱(Nilaparvata lugens)为研究对象,通过RNA干扰(RNA interference,RNAi)技术检测微小RNA(microRNA,miRNA)生物合成通路核心组分NlAgo1、NlDicer1和NlDrosha沉默后褐飞虱鞘脂质代谢通路相关基因的相对转录水平,结合small RNA测序分析沉默丝氨酸棕榈酰转移酶1(serine palmitoyltransferase 1,SPT1)和鞘磷脂酶4(sphingomyelinase 4,SMase4)基因的差异miRNA,探究miRNA在褐飞虱鞘脂质代谢中的作用,为害虫防治提供新的分子靶标。【方法】利用RNAi技术,分别对羽化后第1天(1 PAE,post adult eclosion)的雌成虫NlAgo1、NlDicer1和NlDrosha进行dsRNA注射,以ds GFP为对照;分别解剖羽化后第5天的卵巢组织,以β-actin作为内参基因,采用实时荧光定量PCR(qRT-PCR)方法检测NlAgo1、NlDicer1和NlDrosha沉默后鞘脂质代谢通路相关基因的表达量变化;根据已有的小RNA文库联合miRNA-靶基因预测软件对可能调控NlSPT1和NlSMase4表达的miRNA进行预测;通过small RNA测序技术对沉默NlSPT1和NlSMase4的差异miRNA进行鉴定和靶基因富集性分析。【结果】与对照组相比,沉默NlAgo1、NlDicer1或NlDrosha显著上调卵巢中NlSPT1和NlSMase4等鞘脂质代谢通路相关基因的表达;靶基因预测结果显示,有6条miRNA能与NlSPT1结合,13条miRNA能与NlSMase4结合;沉默NlSPT1和NlSMase4的差异miRNA的靶基因显著富集在细胞核和蛋白质结合等生物学过程以及内吞作用、内质网加工、MAPK信号通路、TOR信号通路、凋亡、脂质代谢等代谢通路。【结论】NlAgo1、NlDicer1和NlDrosha依赖性的miRNA通过影响鞘脂质代谢相关基因的表达影响鞘脂质代谢。NlSPT1和NlSMase4沉默引起褐飞虱卵巢miRNA表达水平的改变。研究结果可为基于鞘脂质代谢基因为靶标的害虫防治提供理论依据。 展开更多
关键词 褐飞虱 微小RNA 鞘脂质 RNA干扰 small RNA测序
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Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory
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作者 Shuang Zhao Hongbin Gu +2 位作者 Lianfang Xue Dongsheng Wang Bin Huang 《Journal of Water Resource and Protection》 CAS 2024年第7期538-556,共20页
The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of trea... The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed. 展开更多
关键词 Optimal Control Theory small and Medium-Sized Enterprises Water Environment Regulation Contract Mechanism
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Assessing Factors Influencing Solar Energy Adoption among Small and Medium Enterprises in Mzuzu City, Malawi
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作者 Mkhalipie Avenea Beatrice Ke Jiang 《Energy and Power Engineering》 2024年第7期257-284,共28页
One of the many renewable energy sources that offer advantages is solar energy, which also lowers energy prices and promotes environmental sustainability and energy security. Despite these advantages, various barriers... One of the many renewable energy sources that offer advantages is solar energy, which also lowers energy prices and promotes environmental sustainability and energy security. Despite these advantages, various barriers, such as installation costs, have prevented small and medium-sized enterprises from investigating this invention. Malawi has a significant energy shortfall such that most businesses have been hindered from their profit maximization goals. The “Photovoltaic systems” (PV) that transform sunlight into electricity are the subject of this study. This type of solar energy system is situated on the building’s roof and generally produces electricity for businesses and even homes. Solar energy offers a great impact to small and medium enterprises in Mzuzu city with a cost-effective and dependable alternative to energy that has the potential to change the game. Therefore the aim of the study was to identify factors that encourage the adoption of solar energy among small medium enterprises in the city of Mzuzu city. And to identify some of barriers faced when adopting solar energy among small and medium enterprises in the city of Mzuzu. The research approach employed in the study was a survey. A survey is a type of research methodology in which primary data is gathered from a sample using a questionnaire. When information is to be gathered from a wider sample, a survey is employed. A bigger sample size was needed in this study in order to facilitate hypothesis testing. It is advised to apply a logical approach while using the survey. The survey utilized a five-point Likert scale. The study used convenience sampling to select study participants. The sample size in this study was determined using Cochran’s sample size formula. Statistical Package for Social Sciences (SPSS) and Microsoft Excel were used for statistical analysis. About 97.2% of the participants were aware of solar as a source of energy compared to 2.8 % who were unaware. The majority of participants use solar energy for lighting only, seconded by those who use electricity. The least number of participants use solar energy for cooling only. The majority of participants 21.5% indicated partnership and collaboration as the most motivating factor for the adoption of solar energy. This was followed by technical expertise 19.1 % the least number of participants 10.8% expressed that policy and regulatory frameworks were associated with the adoption of solar energy. This study found that there are no statistically significant factors influencing barriers to the adoption of solar energy. The price of solar energy adoption was identified as the least factor associated with the acceptance or rejection of solar energy. Nonetheless, the reasons given by the homes that had embraced solar technology aligned with the findings of other studies. This survey also found that although the public was aware of solar energy, and technology, there were still a number of factors that mattered, especially for non-adopters. 展开更多
关键词 Solar Energy small and Medium Enterprises Solar Energy Adoption
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Small Cell Neuroendocrine Carcinoma of the Vulva: Case Report and Literature Review
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作者 Gabriela Françóes Rostirolla Alessandra Guerra +4 位作者 Maria Carolina Rey Alt Luiza Tesser Dalla Libera Maria Eduarda Appel Binda Márcia Appel Fernando De Marco dos Santos 《Open Journal of Obstetrics and Gynecology》 2024年第2期295-300,共6页
Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. Whe... Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. When present, these neoplasms often manifest with nonspecific signs and symptoms such as pain, itching, swelling, single-focus lesions, bleeding, and enlargement of inguinal lymph nodes, in addition to the presence of progressively enlarging vulvar nodules. Consequently, the diagnostic investigation involves histopathological examination and confirmation through immunohistochemistry. Objective: To present a comprehensive understanding of this rarely studied pathology. The primary objective is to provide valuable insights that could aid in the future development of universally applicable treatment guidelines. Case Presentation: A 57-year-old female, with no prior comorbidities, menopause at 36, who presented with a left vulvar nodule accompanied by intense pain and swelling, later diagnosed with small cell neuroendocrine carcinoma in the vulva. Conclusion: This case report highlights the importance of enhancing our knowledge regarding small cell neuroendocrine carcinoma in the vulva, given its scarcity in medical literature. The information presented here underscores the need for standardized diagnostic and treatment approaches, paving the way for future consensus on managing this uncommon but challenging neoplasm. 展开更多
关键词 Vulvar Neoplasms CARCINOMA small Cell CARCINOMA NEUROENDOCRINE Genital Neoplasms FEMALE Vulvar Diseases
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Characterization of Small-Scale Farmers and Assessment of Their Access to Crop Production Information in Selected Counties of Kenya
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作者 Anastasia Mumbi Wahome John B. K. Kiema +1 位作者 Galcano C. Mulaku Isaac Mukoko 《Agricultural Sciences》 2024年第5期565-589,共25页
Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sol... Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits. 展开更多
关键词 small Scale Farmers FARMERS Crop Production Information Services Geospatial Information Information Access
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Immunotherapy for Small Cell Lung Cancer
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作者 Yuxuan Ge Xi Tang 《Journal of Biosciences and Medicines》 2024年第8期320-332,共13页
Small cell lung cancer (SCLC) is a poorly differentiated, highly malignant neuroendocrine tumor characterized by rapid growth, aggressiveness, and easy recurrence. It is usually found in late clinical stage and the op... Small cell lung cancer (SCLC) is a poorly differentiated, highly malignant neuroendocrine tumor characterized by rapid growth, aggressiveness, and easy recurrence. It is usually found in late clinical stage and the opportunity for surgery is lost. Therefore, surgery is often not used in clinical treatment. Although it is sensitive to chemoradiotherapy, it has a high recurrence rate and lacks effective treatment methods at present. Following chemotherapy and radiotherapy, immunotherapy for small cell lung cancer has become the mainstream research direction. Immunotherapy is profoundly changing the approach to cancer treatment due to its tolerable safety profile, sustained treatment response due to the production of immune memory, and effectiveness in a broad patient population. Immunotherapy for small cell lung cancer is one of the effective treatment methods for small cell lung cancer, and relevant studies are not rare, but there are still shortcomings such as intolerance of side effects and inaccurate evaluation of treatment timing. This article reviews the history of immunotherapy, the mechanism of action of immunodrugs, and the current immunodrugs used in the first-line treatment of extensive small cell lung cancer. 展开更多
关键词 small Cell Lung Cancer IMMUNOTHERAPY PD-L1 Inhibitor PD-1 Inhibitor
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Pang Fuwan Uses Yao Medicine to Observe the Therapeutic Effects on the Physical and Mental Symptoms of Patients with Advanced Non-Small Cell Lung Cancer
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作者 Qiuxiang Luo Qiongping Liang Xiaoyan Luo 《Pharmacology & Pharmacy》 2024年第3期62-69,共8页
Objective: Investigate the efficacy and safety of Yao Medicine in the treatment of advanced non-small-cell lung carcinoma, and explore the best therapeutic measure for clinical benefit. Methods: From July 2020 to July... Objective: Investigate the efficacy and safety of Yao Medicine in the treatment of advanced non-small-cell lung carcinoma, and explore the best therapeutic measure for clinical benefit. Methods: From July 2020 to July 2022, 84 patients with advanced non-small-cell lung carcinoma were selected and randomly divided into the Observation Group and control group, and the control group was treated with routine Western medicine, with 42 cases in each group. The activity of daily living (ADL) was assessed before and after treatment, meanwhile, the self-rating depression scale (SDS) and self-rating anxiety SAS (SAS) were used to assess the improvement of a bad mood, and quality of life SF-36 was used to assess the quality of life, to judge the efficacy and safety. Results: The effective rate of observation group was 91.67%. The effective rate of the control group was 76.19%. The effective rate of the observation group was significantly higher than that of the control group (P 0.05). There were no significant differences in the scores of SDS, SAS and quality of life between the two groups before treatment (P > 0.05), and after treatment, the scores of SDS, SAS and quality of life in the two groups were compared with those in the control group (P > 0.05), the scores of VAS, SDS and SAS decreased significantly, while ESCV, angle of straight leg elevation, ADL, physiological score, emotional score, social score and health status score increased significantly, the difference was statistically significant (P 0.05). Conclusion: Yao Medicine can improve the psychosomatic symptoms of patients with advanced non-small-cell lung carcinoma better, with better efficacy and higher safety. 展开更多
关键词 Yao Medicine Non-small-Cell Lung Carcinoma Advanced Stage EFFICACY Physical and Mental
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Analysis and Review of Downregulated Actin Cytoskeletal Proteins in Non-Small Cell Lung Cancer
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作者 Hala M. Abdel Mageed Praveen Sahu Raji Sundararajan 《Journal of Biosciences and Medicines》 2024年第4期89-115,共27页
Actin, a highly conserved protein, plays a dominant role in Non-small cell lung cancer (NSCLC). Late diagnosis and the aggressive nature of NSCLC pose a significant threat. Studying the clinic pathological properties ... Actin, a highly conserved protein, plays a dominant role in Non-small cell lung cancer (NSCLC). Late diagnosis and the aggressive nature of NSCLC pose a significant threat. Studying the clinic pathological properties of NSCLC proteins is a potential alternative for developing treatment strategies. Towards this, 35 downregulated actin cytoskeletal proteins on NSCLC prognosis and treatment were studied by examining their protein-protein interactions, gene ontology enrichment terms, and signaling pathways. Using PubMed, various proteins in NSCLC were identified. The protein-protein interactions and functional associations of these proteins were examined using the STRING database. The focal adhesion signaling pathway was selected from all available KEGG and Wiki pathways because of its role in regulating gene expression, facilitating cell movement and reproduction, and significantly impacting NSCLC. The protein-protein interaction network of the 35 downregulated actin cytoskeleton proteins revealed that ACTG1, ACTR2, ACTR3, ANXA2, ARPC4, FLNA, TLN1, CALD1, MYL6, MYH9, MYH10, TPM1, TPM3, TPM4, PFN1, IQGAP1, MSN, and ZXY exhibited the highest number of interactions. Whereas HSPB1, CTNNA1, KRT17, KRT7, FLNB, SEPT2, and TUBA1B displayed medium interactions, while UTRN, TUBA1B, and DUSP23 had relatively fewer interactions. It was discovered that focal adhesions are critical in connecting membrane receptors with the actin cytoskeleton. In addition, protein kinases, phosphatases, and adapter proteins were identified as key signaling molecules in this process, greatly influencing cell shape, motility, and gene expression. Our analysis shows that the focal adhesion pathway plays a crucial role in NSCLC and is essential for developing effective treatment strategies and improving patient outcomes. 展开更多
关键词 Non-small Cell Lung Cancer NSCLC ACTIN Actin Cytoskeletal Proteins Focal Adhesion KEEG Pathway
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Efficacy and Safety of Primary Radiotherapy in Combination with EGFR-TKIs for Non-Small Cell Lung Cancer Harboring EGFR Mutation
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作者 Dongxu Ao Meng Wang +5 位作者 Jinyuan Xie Yang Zhang Xinran Zhang Ya Shu Chenshi Lin Qingqing Ye 《Journal of Biosciences and Medicines》 2024年第9期142-154,共13页
Objective: To evaluate the efficacy and safety of EGFR-TKI with the radiotherapy in EGFR mutant metastatic NSCLC. Methods: Retrospective analysis of 72 patients with stage IV lung cancer with EGFR-sensitive mutation. ... Objective: To evaluate the efficacy and safety of EGFR-TKI with the radiotherapy in EGFR mutant metastatic NSCLC. Methods: Retrospective analysis of 72 patients with stage IV lung cancer with EGFR-sensitive mutation. Patients in the A group were treated with the first-generation EGFR-TKI (Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor) combined with radiotherapy for primary tumors (34 cases). The B group was treated with the first-generation EGFR-TKI alone until the disease progressed (38 cases). PFS, OS, pulmonary infection and hematological toxicity during treatment were commented in both groups. Results: The objective remission rate was 47.1% (16/34) in the A group and 21.1% (8/38) in the B group. There was a significant difference between the two groups. There was no significant difference in hematological toxicity between the A group and the B group. There were 10 patients (29.4%) with degree II pulmonary infection in the A group and 3 patients (7.9%) in the B group. The difference between the two groups was statistically significant, suggesting that the incidence of pneumonia in the A group was higher than that in the B group. The median PFS (Progression-Free Survival)) and OS (Overall Survival) of the A group were significantly longer than those of the B group (16.5 months vs 9 months) and the median OS (36 months vs 19 months). The PFS and OS in the A group were significantly longer than those in the B group. Conclusion: EGFR-TKI combined with primary radiotherapy can significantly prolong the drug resistance time of EGFR mutant metastatic NSCLC. 展开更多
关键词 Non-small Cell Lung Cancer Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor RADIOTHERAPY
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Small Cell Prostate Cancer;Center Review of Two Cases and Testimony of a Rare and Aggressive Disease
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作者 Makama Baje Salihu Haruna Liman +4 位作者 Stephen Yusuf Dauda Suleiman Shaphat Shuaibu Ibrahim Yusuf Aliyu Salihu Isa Sajo Mienda 《Case Reports in Clinical Medicine》 2024年第9期410-417,共8页
Small cell cancers were initially described in the lungs and later found to occur in a wide range of organs of the body, constituted a disease entity that is characterized by an aggrieve path/course and a huge disease... Small cell cancers were initially described in the lungs and later found to occur in a wide range of organs of the body, constituted a disease entity that is characterized by an aggrieve path/course and a huge disease related mortality. They are also called neuroendocrine tumors with peculiar histologic and biologic disease entity. Here we present two cases of small cell cancer of the prostate seen and managed in our facility with focus on their presentation, disease progression and outcome. The first patient was a 72-year-old retired military officer who presented with a progressively painful scrotal swelling of 3-month duration, and scrotal ulceration with contact bleeding of a month duration associated with a foul-smelling discharge. There was also history of progressive weight lost, loss of appetite and constipation. Patient was pale and lethargic on examination with a foul smelling exophytic scrotal mass. Serum PSA was 4 ng/l (within normal limit). Wedge biopsy and trucut prostate biopsy revealed small cell cancer of the prostate. Patient was resuscitated and prepared for chemoradiation, had a single dose of chemotherapy and died before the second dose. Second patient was a 63-year-old farmer who presented with lower urinary tract symptoms, progressive weight loss and constipation of two months duration, a known hypertensive and diabetic who has been regular on his medication. He was lethargic on examination, pale and unable to stand without support. Trucut prostate biopsy shows small cell cancer of the prostate. He was also resuscitated and being prepared for chemoradiation but died before commencement of treatment. 展开更多
关键词 small Cell PROSTATE Cancer Mortality CHEMORADIATION
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A Review of Cybersecurity Challenges in Small Business: The Imperative for a Future Governance Framework
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作者 Binita Saha Zahid Anwar 《Journal of Information Security》 2024年第1期24-39,共16页
Technological shifts—coupled with infrastructure, techniques, and applications for big data—have created many new opportunities, business models, and industry expansion that benefit entrepreneurs. At the same time, ... Technological shifts—coupled with infrastructure, techniques, and applications for big data—have created many new opportunities, business models, and industry expansion that benefit entrepreneurs. At the same time, however, entrepreneurs are often unprepared for cybersecurity needs—and the policymakers, industry, and nonprofit groups that support them also face technological and knowledge constraints in keeping up with their needs. To improve the ability of entrepreneurship research to understand, identify, and ultimately help address cybersecurity challenges, we conduct a literature review on the state of cybersecurity. The research highlights the necessity for additional investigation to aid small businesses in securing their confidential data and client information from cyber threats, thereby preventing the potential shutdown of the business. 展开更多
关键词 ENTREPRENEURSHIP CYBERSECURITY small and Medium Businesses Data Breach HACKING Security
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CT放射组学鉴别诊断周围型小细胞肺癌和非小细胞肺癌的价值研究
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作者 靳强 高俊萍 +2 位作者 王欢 江涛 孙红红 《中国CT和MRI杂志》 2025年第1期47-49,共3页
目的 本研究旨在评估C T放射学方法鉴别周围型小细胞肺癌和非小细胞肺癌的研究,以期为临床诊治提供参考。方法回顾性研究原发性肺癌患者的临床资料,利用诊断后、治疗前的肺部CT图像对肺癌进行分割。从基于直方图的统计、肿瘤图像纹理分... 目的 本研究旨在评估C T放射学方法鉴别周围型小细胞肺癌和非小细胞肺癌的研究,以期为临床诊治提供参考。方法回顾性研究原发性肺癌患者的临床资料,利用诊断后、治疗前的肺部CT图像对肺癌进行分割。从基于直方图的统计、肿瘤图像纹理分析及其小波变换中提取放射学特征。特征选择采用最小冗余度和最大相关法。用多层人工神经网络建立预测模型,用受试者工作特征曲线(AUC)下面积评价SCLC/NSCLC腺癌分类器的性能。结果69例小细胞肺癌和34例非小细胞肺癌患者相比,小细胞肺癌组男性患者和吸烟者多于非小细胞肺癌组(P<0.05)。我们的SCLC/NSCLC分类器的总体性能AUC为0.93(95%可信区间=[0.85,0.97],灵敏度=0.85,特异度=0.85)。添加如吸烟史等临床数据,可略微改善性能。排名最靠前的放射学特征主要是纹理特征。结论 CT放射组学能定量反映肿瘤的异质性,可用于肺癌亚型的鉴别诊断,效果满意。用小波变换技术对CT图像进行处理,增强了小细胞肺癌/非小细胞肺癌的放射学特征。 展开更多
关键词 CT 周围型小细胞肺癌 非小细胞肺癌 放射学特征
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Effective Utilization of Government-Provided CTI by Small Businesses within the Defense Industrial Base
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作者 Josiah Dykstra Lawrence A. Gordon +2 位作者 Martin P. Loeb Benjamin Wall Lei Zhou 《Journal of Information Security》 2024年第2期196-217,共22页
There are two broad objectives of the research reported in this paper. First, we assess whether government-provided cyber threat intelligence (CTI) is helpful in preventing, or responding to, cyber-attacks among small... There are two broad objectives of the research reported in this paper. First, we assess whether government-provided cyber threat intelligence (CTI) is helpful in preventing, or responding to, cyber-attacks among small businesses within the U.S. Defense Industrial Base (DIB). Second, we identify ways of improving the effectiveness of government-provided CTI to small businesses within the DIB. Based on a questionnaire-based survey, our findings suggest that government-provided CTI helps businesses within the DIB in preventing, or responding to, cyber-attacks providing a firm is familiar with the CTI. Unfortunately, a large percentage of small firms are not familiar with the government-provided CTI feeds and consequently are not utilizing the CTI. This latter situation is largely due to financial constraints confronting small businesses that prevent firms from having the wherewithal necessary to effectively utilize the government-provided CTI. However, we found a significant positive association between a firm’s familiarity with the government-provided CTI and whether a firm is being periodically reviewed by the Defense Counterintelligence and Security Agency (DCSA) or is compliant with the Cybersecurity Maturity Model Certification (CMMC) program. The findings from our study also show that the participating firms believe that external cyber threats are more likely to be the cause of a future cybersecurity breach than internal cybersecurity threats. Finally, our study found that the portion of the IT budget that small businesses within the DIB spend on cybersecurity-related activities is dependent on the perception that a firm would be the target of an external cyber-attack. 展开更多
关键词 Government-Provided CTI small Businesses Defense Industrial Base
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小肠黏膜下层脱细胞基质复合外泌体构建组织工程尿道
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作者 王丹 朱小军 +1 位作者 李志成 李娜 《中国组织工程研究》 CAS 北大核心 2025年第23期4907-4914,共8页
背景:小肠黏膜下层脱细胞基质已被临床与基础研究证实可用于尿道的修复重建,但其单独应用时存在宿主细胞生长缓慢、支架血管化不足而成活困难、重建尿道狭窄梗阻等问题,仅适用于较短的尿道狭窄。目的:探讨应用小肠黏膜下层脱细胞基质复... 背景:小肠黏膜下层脱细胞基质已被临床与基础研究证实可用于尿道的修复重建,但其单独应用时存在宿主细胞生长缓慢、支架血管化不足而成活困难、重建尿道狭窄梗阻等问题,仅适用于较短的尿道狭窄。目的:探讨应用小肠黏膜下层脱细胞基质复合外泌体构建组织工程尿道的可行性。方法:从新西兰大白兔骨髓间充质干细胞中分离提取外泌体;制备猪小肠黏膜下层脱细胞基质,将外泌体负载于小肠黏膜下层脱细胞基质上。将小肠黏膜下层脱细胞基质-外泌体(PKH26染料标记)复合物与脐静脉内皮细胞共培养12 h,观察细胞摄取外泌体情况。选取生长状态良好的脐静脉内皮细胞,分3组培养:空白组常规培养,对照组加入小肠黏膜下层脱细胞基质,实验组加入小肠黏膜下层脱细胞基质-外泌体复合物,通过划痕实验、成管实验、血管生成因子分泌检测评估血管生成情况。取30只新西兰大白兔,建立长段(3 cm)尿道缺损模型,采用随机数字表法分3组干预(n=10):单独材料组植入小肠黏膜下层脱细胞基质,对照组植入小肠黏膜下层脱细胞基质-骨髓间充质干细胞复合物,实验组植入小肠黏膜下层脱细胞基质-外泌体复合物,植入后12周进行尿道造影、尿动力学检查及重建尿道切片病理观察。结果与结论:(1)荧光显微镜下可见小肠黏膜下层脱细胞基质中的外泌体可被脐静脉内皮细胞摄取。(2)与空白组、对照组相比,实验组材料可促进脐静脉内皮细胞的迁移、成血管能力以及成血管因子血管内皮生长因子、肝细胞生长因子、白细胞介素8的分泌(P <0.05)。(3)尿道造影结果显示,单独材料组10只兔均出现尿道狭窄,对照组10只兔中2只出现尿道狭窄,实验组10只兔均未出现尿道狭窄。尿动力检查结果显示,单独材料组兔材料植入后12周的最大尿道压高于术前(P <0.05),对照组、实验组兔植入后12周的最大尿道压均低于空白组(P <0.05)。苏木精-伊红、Masson与免疫组化染色显示,单独材料组可见明显的再生上皮层、少量的皮下平滑肌与血管,以纤维组织增生为主,伴有明显炎性细胞浸润;对照组可见较完整的再生上皮与少量胶原,可见大量的皮下血管与平滑肌,伴有炎性细胞浸润;实验组可见完整的再生上皮层与大量的皮下血管、平滑肌,未见明显炎性细胞浸润,实验组AE1/AE3、ɑ-平滑肌肌动蛋白、CD31阳性表达均高于单独材料组、对照组(P <0.05)。(4)结果表明,小肠黏膜下层脱细胞基质-外泌体组织工程尿道可通过促进血管生成来修复尿道缺损。 展开更多
关键词 尿道损伤 尿道狭窄 小肠黏膜下层脱细胞基质 细胞外基质 外泌体 组织工程尿道
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A Model of Cloud-Based Enterprise Resource Planning (ERP) for Small and Medium Enterprise
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作者 Mohammad Jahangir Alam Shoman Das Sharma Tanjia Chowdhury 《Journal of Computer and Communications》 2024年第10期37-50,共14页
Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced fe... Cloud Computing is an uprising technology in the rapid growing IT world. The adaptation of cloud computing is increasing in very large scale business organizations to small institutions rapidly due to many advanced features of cloud computing, such as SaaS, PaaS and IaaS service models. So, nowadays, many organizations are trying to implement Cloud Computing based ERP system to enjoy the benefits of cloud computing. To implement any ERP system, an organization usually faces many challenges. As a result, this research has introduced how easily this cloud system can be implemented in an organization. By using this ERP system, an organization can be benefited in many ways;especially Small and Medium Enterprises (SMEs) can enjoy the highest possible benefits from this system. 展开更多
关键词 Cloud Computing Cloud Comparison Cloud Models Enterprise Resource planning (ERP) small and Medium Enterprise (SME)
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改进YOLOv8的无人机航拍图像目标检测算法
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作者 梁燕 何孝武 +1 位作者 邵凯 陈俊宏 《计算机工程与应用》 北大核心 2025年第1期121-130,共10页
针对无人机航拍图像存在多个小目标聚集、目标尺度变化大的问题,提出一种改进YOLOv8的目标检测算法TS-YOLO(tiny and scale-YOLO)。在主干部分去除冗余的特征提取层,设计了一种高效特征提取模块(efficient feature extraction module,EF... 针对无人机航拍图像存在多个小目标聚集、目标尺度变化大的问题,提出一种改进YOLOv8的目标检测算法TS-YOLO(tiny and scale-YOLO)。在主干部分去除冗余的特征提取层,设计了一种高效特征提取模块(efficient feature extraction module,EFEM),避免小目标特征消失在冗余信息中。在颈部设计了一种双重跨尺度加权特征融合方法(dual cross-scale weighted feature-fusion,DCWF),融合多尺度信息的同时抑制噪声干扰,提升特征表达能力。通过构建一种参数共享检测头(parameter-shared detection header,PSDH),使回归和分类任务实现参数共享,保证检测精度的同时有效降低了模型的参数量。所提模型在VisDrone-2019数据集上的精度(P)和召回率(R)分别达到54.0%、42.5%;相比于原始YOLOv8s模型,mAP50提高了5.0个百分点,达到44.5%,且参数量减少了55.8%,仅有4.94×106;在DOTAv1.0遥感数据集上,mAP50达到71.9%,仍具有较好的泛化能力。 展开更多
关键词 目标检测 无人机航拍图像 YOLOv8 小目标 特征融合
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The Regularity of Solutions to Mixed Boundary Value Problems of Second-Order Elliptic Equations with Small Angles
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作者 Mingyu Wu 《Journal of Applied Mathematics and Physics》 2024年第4期1043-1049,共7页
This paper considers the regularity of solutions to mixed boundary value problems in small-angle regions for elliptic equations. By constructing a specific barrier function, we proved that under the assumption of suff... This paper considers the regularity of solutions to mixed boundary value problems in small-angle regions for elliptic equations. By constructing a specific barrier function, we proved that under the assumption of sufficient regularity of boundary conditions and coefficients, as long as the angle is sufficiently small, the regularity of the solution to the mixed boundary value problem of the second-order elliptic equation can reach any order. 展开更多
关键词 Mixed Boundary Value Problems for Elliptic Equations small-Angle Boundary Value Problems Regularity of Solutions to Elliptic Equations
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单孔电视胸腔镜手术与常规胸腔镜手术在非小细胞肺癌根治术中的应用价值
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作者 郭亮 贾明选 +1 位作者 马文杰 闫宪飞 《罕少疾病杂志》 2025年第1期63-65,共3页
目的 探讨单孔电视胸腔镜手术在非小细胞肺癌根治术中的效果。方法 选取河南科技大学附属黄河三门峡医院2021年1月至2023年1月收治的100例非小细胞肺癌患者,分为对照组50例(常规胸腔镜手术),观察组50例(单孔电视胸腔镜手术),分组方法为... 目的 探讨单孔电视胸腔镜手术在非小细胞肺癌根治术中的效果。方法 选取河南科技大学附属黄河三门峡医院2021年1月至2023年1月收治的100例非小细胞肺癌患者,分为对照组50例(常规胸腔镜手术),观察组50例(单孔电视胸腔镜手术),分组方法为随机数字表法。比较两组临床指标。结果 观察组引流管留置时间、住院时间短于对照组(P<0.05);观察组术后1d、2d、3d的疼痛评分均低于对照组(P<0.05);观察手术后组血清生长激素、PGE2、Cor水平低于对照组(P<0.05),各项临床症状评分均高于对照组(P<0.05),并发症发生率低于对照组(P<0.05)。结论 非小细胞肺癌根治术患者应用单孔电视胸腔镜手术对缩短住院时间、缓解临床症状、降低疼痛水平、减轻应激反应方面具有积极作用,更利于患者康复。 展开更多
关键词 非小细胞肺癌 单孔电视胸腔镜 临床症状 应激反应 疼痛水平
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基于小流域山坪塘沉积泥沙^(137)Cs的泥沙沉积剖面粒径特征
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作者 成六三 《节水灌溉》 北大核心 2025年第1期96-101,共6页
小流域泥沙来源分析对流域综合治理与水土保持措施评价具有重要意义。选择岩溶区小流域山坪塘为例,从山坪塘沉积泥沙入手,探明山坪塘沉积泥沙剖面与其控制流域内的土地利用类型的^(137)Cs比活度和及黏粒含量的深度分布特征,为反演小流... 小流域泥沙来源分析对流域综合治理与水土保持措施评价具有重要意义。选择岩溶区小流域山坪塘为例,从山坪塘沉积泥沙入手,探明山坪塘沉积泥沙剖面与其控制流域内的土地利用类型的^(137)Cs比活度和及黏粒含量的深度分布特征,为反演小流域土壤侵蚀时空强度分布提供基础。研究结果表明:①山坪塘沉积泥沙的^(137)Cs比活度在垂直剖面上变化较为复杂,最大值出现在山坪塘的底顶部,^(137)Cs比活度范围为0.99~3.58 Bq/kg,平均值为1.8 Bq/kg;②山坪塘控制流域内坡耕地、草地和林地表层土壤的^(137)Cs比活度分布差异性较大,且^(137)Cs比活度极差分别为4.16、2.86和6.36 Bq/kg;③山坪塘旋回沉积泥沙与其控制流域内土地利用类型表层土壤的粒径组分含量主要以黏粒、中粉粒和粉粒为主,且它们的粒径组分含量之间比例基本保持一致;④山坪塘沉积泥沙粒径特征参数(中值粒径、众数粒径、体积加权平均粒径和分形维数D)在垂直剖面上变化基本保持一致,而有效粒径变化较为复杂。研究为开展岩溶小流域山坪塘泥沙沉积来源特征演变提供了重要基础。 展开更多
关键词 岩溶小流域 ^(137)Cs 土壤侵蚀 乌江流域
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基于支路模式能量的含光伏电网小干扰稳定灵敏度分析及应用
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作者 刘铖 韩子杨 +1 位作者 刁硕 张宇驰 《电力自动化设备》 北大核心 2025年第1期99-105,114,共8页
为了分析光伏不同接入位置对电力系统小干扰稳定的影响并避免复杂建模,以网络能量作为研究手段,将光伏并网对电力系统低频振荡产生的影响映射于网络中,通过关键支路的模式能量特性表征电网的低频振荡特性。基于此,找出多处光伏并网场景... 为了分析光伏不同接入位置对电力系统小干扰稳定的影响并避免复杂建模,以网络能量作为研究手段,将光伏并网对电力系统低频振荡产生的影响映射于网络中,通过关键支路的模式能量特性表征电网的低频振荡特性。基于此,找出多处光伏并网场景下系统振荡的关键环节,进一步提取网络能量中与每台光伏强相关的状态变量以形成能量光伏分量,在此基础上根据所构建的基于模式能量的光伏灵敏度指标,对灵敏度指标进行排序,得到光伏接入系统不同位置对系统振荡关键环节的影响,并提出光伏增装配置策略。以IEEE 3机9节点系统和新英格兰10机39节点系统为算例进行仿真分析,通过小干扰稳定计算验证所提方法的可行性。 展开更多
关键词 光伏并网系统 支路模式能量 光伏分量 小干扰稳定 灵敏度分析
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