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Root canal therapy combined with endoscopic sinus surgery for odontogenic sinusitis:Efficacy comparison in a cohort study
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作者 Jun-Wen Xiao Ping Yu Zhang Zhao 《World Journal of Clinical Cases》 SCIE 2025年第5期13-21,共9页
BACKGROUND Odontogenic maxillary sinusitis,often triggered by dental issues like periapical periodontitis,significantly contributes to chronic sinusitis,mainly affecting adults around 50 years old,emphasizing the need... BACKGROUND Odontogenic maxillary sinusitis,often triggered by dental issues like periapical periodontitis,significantly contributes to chronic sinusitis,mainly affecting adults around 50 years old,emphasizing the need for a multidisciplinary diagnostic and treatment approach.AIM To investigate the therapeutic effect and clinical value of root canal therapy combined with nasal endoscopic surgery compared with simple root canal the-rapy in the treatment of severe odontogenic maxillary sinusitis caused by peria-pical periodontitis.METHODS The clinical data,diagnosis,and treatment of 200 patients with severe odonto-genic maxillary sinusitis caused by periapical periodontitis from October 2020 to October 2021 were analyzed retrospectively.Among them,63 patients were treated with simple root canal therapy as the control group,and 137 patients were treated with root canal therapy combined with nasal endoscopic surgery as the observation group.The therapeutic effect,Lund-Kennedy endoscopic score,paranasal sinus Lund-Mackay score,complication rate,recurrence rate,and patient satisfaction were compared between the two groups.RESULTS First,we compared the effective rates:23 cases were cured,22 were improved,and 8 were ineffective in the control group,yielding a total effective rate of 84.90%.Meanwhile,97 cases were cured,34 improved,and 6 were ineffective in the observation group,resulting in a total effective rate of 95.62%.The observation group had a higher total effective rate compared with the control group(P<0.05).Second,we compared the Lund–Kennedy endoscopic score.Before treatment,no significant difference(P>0.05)was observed in this score between the two groups.After treatment,the Lund–Kennedy endoscopic score decreased in both groups.The Lund–Kennedy endoscopic score of the observation group at 3 and 6 mo after treatment was lower compared to that of the control group(P<0.05).Third,we compared the Lund–Mackay score of paranasal sinuses.Before treatment,there was no significant difference in this score between the two groups(P>0.05).After treatment,the Lund–Mackay scores of paranasal sinuses decreased in both groups.The Lund–Mackay scores of paranasal sinuses in the observation group at 3 and 6 mo after treatment were lower compared to those of the control group(P<0.05).Fourth,we compared the incidence and recurrence rate of complications.Three months after treatment,no significant difference was found in the incidence and recurrence rate of complications between the observation group(6.56%)and the control group(9.52%)(P>0.05).However,6 mo after treatment,the incidence and recurrence rate of complications in the observation group(2.91%)was significantly higher compared to that of the control group(12.69%)(P<0.05).Fifth,we compared patient satisfaction.Six months after treatment,the patient satisfaction of the observation group(93.43%)was significantly better than that of the control group(84.12%)(P<0.05).CONCLUSION Root canal therapy combined with nasal endoscopic surgery has a good therapeutic effect on severe odontogenic maxillary sinusitis caused by periapical periodontitis,and it can reduce the injury of maxillary sinus mucosa and bone,and significantly reduce the incidence of complications and recurrence rate.Meanwhile,it has high patient satisfaction and remarkable therapeutic effect,which is suggested to be popularized and applied in clinic. 展开更多
关键词 Root canal therapy Nasal endoscopic surgery Periapical periodontitis Odontogenic maxillary sinusitis Therapeutic effect Clinical value
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Mandibular left first premolar with three roots and three canals:A case report
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作者 Cheng-Yi Lin Yue-Yuan Yu 《World Journal of Clinical Cases》 2025年第13期20-28,共9页
BACKGROUND The numbers of mandibular first premolar roots and root canals vary,and the incidence of three roots and three canals is 0.09%.CASE SUMMARY In this article,we review the root and root canal conditions for t... BACKGROUND The numbers of mandibular first premolar roots and root canals vary,and the incidence of three roots and three canals is 0.09%.CASE SUMMARY In this article,we review the root and root canal conditions for the mandibular first premolar and report the case of a mandibular left first premolar with three roots and three canals in a male patient,with suggestions for clinical diagnosis and treatment.The patient was referred by an orthodontist for the extraction of the tooth.Preoperative cone-beam computed tomography examination revealed that it had three roots.Under local anesthesia,the extraction socket was carefully expanded,and the tooth was successfully removed intact using forceps.The procedure was uneventful,with no root fractures,postoperative bleeding,or sensory abnormality observed.CONCLUSION The mandibular first premolar is characterized by multiple roots and canal variations that can increase the difficulty of treatment. 展开更多
关键词 Mandibular first premolar Three roots Three root canals Tooth extraction Case report
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Complete resection of recurrent anal canal cancer using endoscopic submucosal dissection and transanal resection: A case report
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作者 Mayuko Kinoshita Tetsuro Maruyama +7 位作者 Shutaro Hike Takuya Hirosuna Shunsuke Kainuma Kazuya Kinoshita Akira Nakano Gaku Ohira Masaya Uesato Hisahiro Matsubara 《World Journal of Gastrointestinal Endoscopy》 2025年第1期54-60,共7页
BACKGROUND Early anal canal cancer is frequently treated with endoscopic submucosal dis-section(ESD)to preserve anal function.However,if the lesion is in the anal canal,then significant difficulties such as bleeding a... BACKGROUND Early anal canal cancer is frequently treated with endoscopic submucosal dis-section(ESD)to preserve anal function.However,if the lesion is in the anal canal,then significant difficulties such as bleeding and challenges associated with scope manipulation can arise.CASE SUMMARY A 70-year-old woman undergoing follow-up after transverse colon cancer surgery was diagnosed with anal canal cancer extending to the dentate line.The patient underwent a combination of ESD and transanal resection(TAR).The specimen was excised in pieces,which resulted in difficulty performing the pathological evaluation of the margins,especially on the anal side where TAR was performed and severe crushing was observed.Careful follow-up was performed,and local recurrence was observed 3 years postoperatively.Because the patient had super-ficial cancer without lymph node metastasis,local resection was performed again.The second treatment attempt was improved as follows:(1)TAR and ESD were performed appropriately based on the situation by the same physician;(2)A needle scalpel was used during TAR to prevent tissue crushing;and(3)The lesion borders were marked using ESD techniques before treatment.Complete resection was performed without complications.CONCLUSION Anal canal lesions can be safely and reliably removed when ESD and TAR are used appropriately. 展开更多
关键词 Anal canal cancer RECURRENCE Endoscopic submucosal dissection Transanal resection Case report
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Peat properties of a tropical forest reserve adjacent to a fire-break canal
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作者 Dayang Nur Sakinah Musa Mohd Zahirasri Mohd Tohir +3 位作者 Xinyan Huang Luqman Chuah Abdullah Mohamad Syazaruddin Md Said Muhammad Firdaus Sulaiman 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期155-167,共13页
Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit gr... Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves. 展开更多
关键词 Peat fire Peat properties Fire-break canals Forest reserves
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Steel bar penetrating cervical spinal canal without neurological injury:A case report
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作者 Qin Zhang Tao Ding +1 位作者 Xiao-Feng Gu Yi Liu 《World Journal of Clinical Cases》 SCIE 2024年第17期3214-3220,共7页
BACKGROUND We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures.CASE SUMMARY A 58-year-old male patient was admitted to the emergency department with a steel bar penetr... BACKGROUND We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures.CASE SUMMARY A 58-year-old male patient was admitted to the emergency department with a steel bar penetrating the neck,without signs of neurological deficit.Computed tomography(CT)demonstrated that the steel bar had penetrated the cervical spinal canal at the C6–7 level,causing C6 and C7 vertebral body fracture,C6 left lamina fracture,left facet joint fracture,and penetration of the cervical spinal cord.The steel bar was successfully removed through an open surgical procedure by a multidisciplinary team.During the surgery,we found that the cervical vertebra,cervical spinal canal and cervical spinal cord were all severely injured.Postoperative CT demonstrated severe penetration of the cervical spinal canal but the patient returned to a fully functional level without any neurological deficits.CONCLUSION Even with a serious cervical spinal canal penetrating trauma,the patient could resume normal work and life after appropriate treatment. 展开更多
关键词 Cervical spinal canal Penetrating trauma Steel bar Neurological deficit Case report
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The Millennia-Old Canal Takes on a New Look Nihao!China——2024 China's Grand Canal Tourism Overseas Promotion Season
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作者 Li Peng 《China & The World Cultural Exchange》 2024年第8期10-15,共6页
On the occasion of the 10th anniversary of the Grand Canal's application for the World Heritage status in 2024,with the strong support of the Department of International Cooperation of the National Radio and Telev... On the occasion of the 10th anniversary of the Grand Canal's application for the World Heritage status in 2024,with the strong support of the Department of International Cooperation of the National Radio and Television Administration and the International Tourism Alliance of Silk Road Cities. 展开更多
关键词 GRAND ALLIANCE canal
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Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion
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作者 Orlane Toto Ndome Nassourou Oumarou Haman +4 位作者 Dimitri Fogue Jean Bruno Ndoumou Ronaldo Fonju Anu Indira Baboke Vincent De Paul Djientcheu 《Open Journal of Modern Neurosurgery》 2024年第3期179-189,共11页
Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed co... Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patients with bilateral fixation. At 6 months postoperatively, 51% of patients with unilateral setup had moderate disability compared to 47.4% of patients with bilateral fixation, while 42.9% of patients with unilateral fixation had mild disability compared to 42.1% of patients with bilateral fixation. At 1 year postoperatively, 81.6% of patients who underwent unilateral fixation had only mild disability compared to 73.7% of patients with bilateral fixation. Conclusion: The assessment of quality of life according to the set-up used shows similar results at 3 months, 6 months and 1 year, with no statistically significant differences. Single-sided pedicle screw fixation combined with transforaminal lumbar interbody fusion or mounting has the advantage of being faster, with less bleeding and is less expensive compared to bilateral fixation. 展开更多
关键词 Lumbar Spinal canal STENOSIS INSTRUMENTATION Surgery Quality of Life
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Results Analysis of Surveys Made to Stakeholders in the Pacific Ports in the Panama Canal:A Study Focused to Improve the Efficiency of Loading/Discharging Operations
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作者 Marilyn Y.López Millán F.Xavier Martínez de Osés 《Journal of Traffic and Transportation Engineering》 2024年第6期255-263,共9页
This research aims to analyze the communication process between the different participating actors in the port of Balboa,in the Panamanian Pacific.The starting hypothesis begins with the normal operation of the port i... This research aims to analyze the communication process between the different participating actors in the port of Balboa,in the Panamanian Pacific.The starting hypothesis begins with the normal operation of the port itself.Considering which strategic actions have potential development and which specific strategic actions are proposed for their improvement,the article begins with a discussion of the nature of ports in Panama and their relationships with the Panama Canal,followed by a literary review of all the effects that climate change may have on navigation on the Panamanian Pacific coast.Next,the implication between the coordination and cooperation between the port,the Panama Canal pilots,and the other actors involved with the arrival and departure of vessels from the port will be analyzed.In a third part,the results of the perception of a significant sample of these actors who were surveyed,which are related to the process,are presented.The document concludes with recommendations on how the Panamanian Pacific port can improve its individual interests through the application of improvements derived from the results of the surveys,for more efficient inter-institutional coordination and cooperation. 展开更多
关键词 canal PANAMA ports PACIFIC
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Schlemm’s canal结构和功能调控的研究进展及其在青光眼治疗中的应用
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作者 刘轲莉(综述) 张峰(审校) 《眼科学报》 2024年第12期631-639,共9页
Schlemm管(Schlemm’scanal,SC)作为房水流出的主要通道,通过调节房水外排来维持眼内压的平衡,其结构和功能的异常与高眼压及青光眼的发生发展密切相关。对SC的研究有助于阐明房水外排阻滞的发生机制、探索新的途径以增加房水排出,从而... Schlemm管(Schlemm’scanal,SC)作为房水流出的主要通道,通过调节房水外排来维持眼内压的平衡,其结构和功能的异常与高眼压及青光眼的发生发展密切相关。对SC的研究有助于阐明房水外排阻滞的发生机制、探索新的途径以增加房水排出,从而为降低眼压和青光眼治疗的新药物开发提供基础。目前,对SC发育和功能的调节机制的认识仍然有限,缺乏针对SC的特异性治疗策略。近年来,关于SC细胞命运决定及其结构发育的细胞学机制逐渐被揭示,功能调控的关键分子靶标也相继被发现,这促进了对SC结构和功能调控的深入理解。此外,作为降眼压药物靶点和针对性手术的创新应用也在不断拓展。文章系统回顾SC的结构与功能研究,总结关键的分子和细胞学调控机制,归纳SC靶向药物和手术疗法的最新进展,为青光眼的临床诊治提供了新的思路。 展开更多
关键词 SCHLEMM管 青光眼 房水流出平衡 眼压调节
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漕源之变:引沁济运的兴废与明代治河困局
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作者 吴琦 李想 《安徽史学》 北大核心 2025年第1期26-35,共10页
明初,黄河南北摆动不定,人为分引河流众多,为解决大运河缺水问题,全线引河济运,引沁济运亦深受关注。景泰至成化朝,河臣主持引沁工程,实现了运河对沁河水多个方向的引用。弘治至嘉靖朝,治沁以筑堤疏浚为主,引沁工程的实施艰难,成为漕源... 明初,黄河南北摆动不定,人为分引河流众多,为解决大运河缺水问题,全线引河济运,引沁济运亦深受关注。景泰至成化朝,河臣主持引沁工程,实现了运河对沁河水多个方向的引用。弘治至嘉靖朝,治沁以筑堤疏浚为主,引沁工程的实施艰难,成为漕源的备用方案。隆庆至万历朝,围绕引沁入卫产生了一系列争论与矛盾,诸如朝中合流派与分流派治河理念之争、百姓生计与国家治漕之争、沁河上下游利益之争等。在漕运至上和黄河水环境变化的背景下,沁河在嘉靖朝中期以后经历了功能和地位的变化,民生与漕源的矛盾最终在保漕目的下得以调和。引沁济运的兴废反映出明代治河中的内在困局。 展开更多
关键词 明代 引沁济运 黄河 沁河
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大运河沿线居民遗产责任行为影响机制研究——基于计划行为理论视角
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作者 张磊玲 《江苏商论》 2025年第2期7-11,20,共6页
地方居民是大运河文化遗产保护传承的重要主体,其遗产责任行为对大运河文化遗产可持续发展至关重要。本研究引入地方依恋理论,以大运河苏州段为例,采用结构方程模型验证居民地方依恋、TPB与遗产责任行为之间的关系。结果表明:(1)居民地... 地方居民是大运河文化遗产保护传承的重要主体,其遗产责任行为对大运河文化遗产可持续发展至关重要。本研究引入地方依恋理论,以大运河苏州段为例,采用结构方程模型验证居民地方依恋、TPB与遗产责任行为之间的关系。结果表明:(1)居民地方依赖和地方认同显著正向影响TPB的三个维度;(2)TPB的三个维度显著正向影响居民遗产责任行为;(3)TPB的三个维度在居民地方依恋和遗产责任行为之间起中介作用。因此,大运河沿线地区应开发文创体验产品和各类消费场景,以增强地方居民与文化遗产的情感联结,从而促使其形成遗产责任行为。 展开更多
关键词 遗产地居民 遗产责任行为 大运河苏州段 计划行为理论
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Study on Tissue Culture of Leucophyta brownii ‘Canal Rocks Form’ 被引量:1
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作者 李艳敏 孟月娥 +3 位作者 赵秀山 王利民 王慧娟 张和臣 《Agricultural Science & Technology》 CAS 2013年第2期230-234,共5页
[Objective] This study aimed to establish a tissue culture technology for Leucophyta brownii ‘Canal Rocks Form’. [Method] Leucophyta brownii ‘Canal Rocks Form’ stems with axillary buds were selected as explants in... [Objective] This study aimed to establish a tissue culture technology for Leucophyta brownii ‘Canal Rocks Form’. [Method] Leucophyta brownii ‘Canal Rocks Form’ stems with axillary buds were selected as explants in vitro to investigate the effects of different concentrations of 6-BA and NAA on proliferation culture and the effects of IBA, NAA and subculture cycle on rooting culture. [Result] The results showed that Leucophyta brownii ‘Canal Rocks Form’ plantlets need low concentrations of phytohormones and the rooting culture was significantly affected by the subculture cycle; the optimal medium for proliferation culture was MS+0.5 mg/L 6-BA+0.05 mg/L NAA+30 g/L sucrose+5.5 g/L agar, with a proliferation coefficient of 4.25; the plantlets with a subculture cycle of 28 d were the most suitable for rooting culture, with a rooting rate of 95.9% in 1/2 MS+0.1 mg/L IBA+0.05 mg/L NAA+20 g/L sucrose+5.5 g/L agar, and the average number and length of roots were 4.69 and 1.68 cm, respectively. [Conclusion] This study laid the foundation for establishing sterile culture system of Leucophyta brownii ‘Canal Rocks Form’. 展开更多
关键词 Leucophyta brownii canal Rocks Form’ Propagation ROOTING Subculture cycle
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Comprehensive evaluation of water quality parameters in Tianjin Dagu Dainage Canal 被引量:1
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作者 董玉波 戴媛媛 +1 位作者 马超 孙学亮 《Marine Science Bulletin》 CAS 2014年第2期90-96,共7页
In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons... In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons in 2012 - 2013 are selected, and Water Quality Pollution Index (API) is applied to evaluate water quality indices, aiming for the systematic evaluation of the water quality of Dagu Dainage Canal. The results showed that four stations of D3, D6, D7and D9 for S2 had the type Ⅱand Ⅲ of water; others had the type Ⅰ ; the total level of TOC, TPH, Cu, Pb, Zn, Cd, Hg, As and Cr were type Ⅰ, Ⅳ, Ⅱ, Ⅴ, Ⅱ, Ⅴ, Ⅲ, Vand Ⅴ. Water Quality Pollution Index (API) was 3.28, which illustrated Dagu Dainage Canal was in the state of contamination and the degree of pollution exceeded the standard functional areas. 展开更多
关键词 Dagu Dainage canal water quality indices spatial and temporadistribution comprehensive evaluation
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有限元分析牙髓根尖周病根管治疗中的牙体力学性能
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作者 杨文静 格根塔娜 《中国组织工程研究》 CAS 北大核心 2025年第20期4295-4304,共10页
背景:根管治疗后牙髓根尖周病变患牙往往因失去较多健康牙体组织等原因导致抗折强度降低,如何增强牙齿抗折强度一直是临床医生密切关注的问题。有限元分析能直观地展示不同状态下患牙各个部分的受力情况,对牙体结构和材料力学性能等进... 背景:根管治疗后牙髓根尖周病变患牙往往因失去较多健康牙体组织等原因导致抗折强度降低,如何增强牙齿抗折强度一直是临床医生密切关注的问题。有限元分析能直观地展示不同状态下患牙各个部分的受力情况,对牙体结构和材料力学性能等进行综合分析。目的:综述有限元分析在牙髓根尖周病根管治疗中的应用进展,并对未来的发展趋势进行展望。方法:在PubMed、Web of Science数据库和中国知网、万方数据库、维普数据库、中国生物医学文献服务系统中检索使用有限元法分析牙髓根尖周病根管治疗的相关文献,英文检索词为“FEA,finite element analysis,stress analysis,root canal treatment,pulp opening,root canal preparation,root canal filling,restoration”,中文检索词为“有限元分析,应力分析,牙髓根尖周病,根管治疗,开髓,根管预备,根管充填,修复”,最终纳入103篇文献进行综述。结果与结论:有限元分析可以通过构建牙体及周围组织的有限元模型分析牙齿在咀嚼、咬合等过程中的应力分布和变形情况。借助有限元分析,临床研究者能够对牙髓根尖周病根管治疗中不同开髓洞型、根管预备方式、根管充填材料及修复方案等对牙体力学性能的影响进行分析,从而选择出最佳的治疗方案,提高治疗效果和患者预后。有限元分析有助于医生在临床治疗中减少牙体组织的损失,提高治疗效果和患者预后。有限元模型是对实际情况的简化,需结合临床试验进行综合分析。 展开更多
关键词 有限元分析 应力分析 牙髓根尖周病 根管治疗 开髓 根管预备 根管充填 修复 工程化口腔材料
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成人椎管内非典型脉络丛乳头状瘤一例
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作者 冉云龙 金凤 +4 位作者 王凯 白小龙 田晓燕 郭欢萱 李振鑫 《磁共振成像》 北大核心 2025年第1期165-166,169,共3页
本文为回顾性研究,遵守《赫尔辛基宣言》,经过内蒙古医科大学附属医院伦理委员会批准,批准文号:KY2024074,受试者在回访时签署了知情同意书。患者女,56岁,因“腰腿部疼痛半年余,加重1月”于2023年9月11日收入内蒙古医科大学附属医院神... 本文为回顾性研究,遵守《赫尔辛基宣言》,经过内蒙古医科大学附属医院伦理委员会批准,批准文号:KY2024074,受试者在回访时签署了知情同意书。患者女,56岁,因“腰腿部疼痛半年余,加重1月”于2023年9月11日收入内蒙古医科大学附属医院神经外科。 展开更多
关键词 脉络丛乳头状瘤 非典型 椎管 磁共振成像
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Ecological Design of Flood Discharging Canals in Shijiazhuang City
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作者 伊红珊 刘辉芳 《Journal of Landscape Research》 2009年第5期1-6,17,共7页
From the perspective of ecological conservation and satisfaction of people's visual and psychological demands,existing problems in the urban revetment were analyzed,and the connotation of ecological revetment as w... From the perspective of ecological conservation and satisfaction of people's visual and psychological demands,existing problems in the urban revetment were analyzed,and the connotation of ecological revetment as well as the selection of different ecological revetments according to different types of river ways was discussed. 展开更多
关键词 GARDEN FLOOD DISCHARGING canal REVETMENT Landscape
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微生物加固渠基粉土的冻融特性及微细观机理研究
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作者 朱锐 邢玮 +3 位作者 郭万里 黄英豪 周峰 王旭东 《岩土工程学报》 北大核心 2025年第2期376-387,共12页
渠基土性能冻融劣化是中国季冻区渠道结构损坏的主要原因,渠基土加固是保障供水渠道安全运行的重要手段。结合微生物岩土加固技术,开展微生物加固渠基粉土系列宏微观室内试验,刻画不同胶结液浓度、养护龄期、冻融循环下加固渠基粉土的... 渠基土性能冻融劣化是中国季冻区渠道结构损坏的主要原因,渠基土加固是保障供水渠道安全运行的重要手段。结合微生物岩土加固技术,开展微生物加固渠基粉土系列宏微观室内试验,刻画不同胶结液浓度、养护龄期、冻融循环下加固渠基粉土的体变率、渗透系数、孔隙率等宏微观指标的发展规律及其定量联系。结果表明:在不同胶结液浓度、养护龄期下,微生物加固可使得渠基粉土的冻融体变量削减约70%,渗透系数至少降低一个数量级、抗压强度提升约220.17%,抗剪强度指标最高增长约65.50%;当胶结液浓度为1.00 mol/L,养护龄期为28 d时,冻融循环下渠基粉土的微生物加固效果最优。此外,微生物诱导生成的碳酸钙沉淀通过填充、胶结、包裹等系列方式重塑了渠基粉土的微细观结构,使其在冻融风化作用下仍然保持整体性和完整性,这是微生物加固渠基粉土在冻融环境下仍然展现出良好工程特性的主要原因。 展开更多
关键词 微生物诱导碳酸钙沉淀 粉土 渠道边坡 冻融循环 微观结构
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高声强冲击波作用人耳动态响应特性
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作者 李冈 胡钟铃 +3 位作者 胡滨 李智宇 蔡萌 黄土顺 《兵工学报》 北大核心 2025年第1期220-234,共15页
为研究冲击波作用下的人耳动态响应特性,设计并开展基于某单兵火箭类武器发射环境的有/无佩戴护听器装置试验研究。在分析发射冲击波特性的基础上,设计制作人耳测试装置模型,形成耳内冲击波防护试验测试方法。通过在射手位置处布设人耳... 为研究冲击波作用下的人耳动态响应特性,设计并开展基于某单兵火箭类武器发射环境的有/无佩戴护听器装置试验研究。在分析发射冲击波特性的基础上,设计制作人耳测试装置模型,形成耳内冲击波防护试验测试方法。通过在射手位置处布设人耳测试装置模型以获取人耳内压力-时间变化曲线,并采用超压传感器测量对比位置处的自由场冲击波压力。利用小波分析法对测到的数据进行分析,对比分析2种发射冲击波安全限值的评价方法。研究结果表明:发射时的高声强冲击波具有不稳定性,超压峰值高,持续时间短,具有多个脉冲;高声强冲击波频带宽,成分复杂,有明显的低频率高声压特性;无护听器装置时耳内压力有所增强;佩戴护听器装置后可大幅度削弱冲击波对人耳的作用,正射手右耳超压峰值削弱95.7%、声压级峰值削弱14.8%;改进后的国家军用标准GJB 2A—1996“常规兵器发射或爆炸时脉冲噪声和冲击波对人员听觉器官损伤的限值”和美军标MIL-STD-1474E“Department of defense design criteria standard noise limits”中AHAAH模型2种方法得到的单日允许射击数范围接近,对佩戴护听器装置后的冲击波测量曲线评估的方法是可行的。研究结果可为单兵火箭类武器发射冲击波测试系统优化及改进提供理论基础和实践指导。 展开更多
关键词 单兵火箭类武器 高声强冲击波 耳道 耳罩 允许日暴露次数
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Gold热处理镍钛锉在模拟S形根管内的抗疲劳折断性能
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作者 陈文新 侯晓玫 《北京大学学报(医学版)》 北大核心 2025年第1期136-141,共6页
目的:比较不同温度下3种新型热处理镍钛锉在模拟S形根管内的抗疲劳折断性能,为临床应用提供依据。方法:选取Gold热处理镍钛锉TruNatomy[25 mm长,26号/0.04锥度(尖段)]与ProTaper Gold[25 mm长,25号/0.08锥度(尖段)]作为实验组,M丝技术... 目的:比较不同温度下3种新型热处理镍钛锉在模拟S形根管内的抗疲劳折断性能,为临床应用提供依据。方法:选取Gold热处理镍钛锉TruNatomy[25 mm长,26号/0.04锥度(尖段)]与ProTaper Gold[25 mm长,25号/0.08锥度(尖段)]作为实验组,M丝技术镍钛锉ProTaper Next[25 mm长,25号/0.06锥度(尖段)]作为对照组,每种镍钛锉各20支。TruNatomy镍钛锉经过Gold热处理使R相变分离,存在完全的中间R相,使柔软度提高;ProTaper Gold镍钛锉为CM丝镍钛锉,用热处理提高相变温度,常温下以马氏体为主,使柔软度提高,表面经Gold热处理产生中间R相;ProTaper Next镍钛锉则采用M丝技术,M丝常温下以奥氏体为主,经过热机械处理引入硬化马氏体,此类马氏体不参与相变,其弹性模量低于奥氏体,从而使镍钛锉柔软度增高。使用双弯金属模拟根管,分别在室温(24℃)及加热至65℃时检测3种镍钛锉的抗疲劳折断性能,不同温度下的每种镍钛锉各10支(n=10)。对相同温度下不同镍钛锉的疲劳折断圈数(number of cyclic fatigue,NCF)以及折断段长度数据采用单因素方差分析,并进行组间比较,以双侧P<0.05为差异有统计学意义。对相同镍钛锉不同温度下的NCF以及折断段长度数据采用配对样本t检验,并进行两两比较,检验水准均为双侧α=0.05。用扫描电镜进行折断镍钛锉断口分析。结果:3种镍钛锉均为在根尖弯曲处首先发生折断,随后在冠方弯曲处发生折断。室温下,根尖段NCF:Tru-Natomy镍钛锉为344.4±96.6,ProTaper Gold镍钛锉为175.0±56.1,ProTaper Next镍钛锉为133.3±39.7,TruNatomy镍钛锉最高(P<0.05);冠方段NCF:TruNatomy镍钛锉为618.3±75.3,ProTaper Gold镍钛锉为327.5±111.8,ProTaper Next镍钛锉为376.6±67.9,TruNatomy镍钛锉仍为最高(P<0.05)。根尖及冠方折断段长度各组间差异无统计学意义(P>0.05)。加热至65℃,根尖段NCF:TruNatomy镍钛锉为289.6±65.8,ProTaper Gold镍钛锉为187.5±75.4,ProTaper Next镍钛锉为103.0±38.5,TruNatomy镍钛锉最高(P<0.05);冠方段NCF:TruNatomy镍钛锉为454.2±45.4,ProTaper Gold镍钛锉为268.3±31.4,ProTaper Next镍钛锉为283.8±31.7,TruNatomy镍钛锉仍为最高(P<0.05)。与室温相比,TruNatomy镍钛锉冠方段在65℃时的NCF显著下降(P<0.05)。各组镍钛锉断口均符合典型的疲劳折断断口特征。结论:Gold热处理镍钛锉在S形弯曲根管中的抗疲劳折断性能优于M丝镍钛锉。 展开更多
关键词 镍钛根管锉 S形根管 抗疲劳折断性能 热处理
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北京温榆河公园鸟类多样性特征与生境优化策略
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作者 杨宇琢 李垣霏 +7 位作者 雷国龙 王苧卉 房华 吴岚 唐瑞 黄赓 李志刚 王玉玉 《环境科学研究》 北大核心 2025年第1期49-58,共10页
北京温榆河公园位于北京市第二道绿化隔离地区,是依托北京温榆河−北运河生态廊道建设而成的超大城市级绿色空间,研究其鸟类多样性特征,优化其生境质量对维持北京地区的生物多样性具有重要意义。根据北京温榆河公园2022年1月−2023年12月... 北京温榆河公园位于北京市第二道绿化隔离地区,是依托北京温榆河−北运河生态廊道建设而成的超大城市级绿色空间,研究其鸟类多样性特征,优化其生境质量对维持北京地区的生物多样性具有重要意义。根据北京温榆河公园2022年1月−2023年12月的鸟类多样性调查数据,详细识别公园内鸟类的群落结构并划分不同的鸟类取食集团,分析不同季节的鸟类多样性时空特征与多样性热点区域;根据遥感解译与植被多样性调查结果对研究区域的生境类型进行划分,针对具有不同鸟类群落特征的生境类型提出具体的优化方案。结果表明:①在北京温榆河公园共调查到鸟类174种,隶属于19目51科,其中,有国家Ⅰ级重点保护物种4种,国家Ⅱ级重点保护物种21种。②北京温榆河公园鸟类的α-多样性在春季最高,温榆河主河道具有最高的鸟类多度和多样性指数。③北京温榆河公园可划分为生境类型Ⅰ(滨水湿地+乔灌林地)、生境类型Ⅱ(密林地)、生境类型Ⅲ(滨水湿地+疏林地)3种生境组合。根据不同生境中的鸟类群落特征差异有针对性地提出生境优化策略,建议生境类型Ⅰ在维护湿地生境的同时提高陆生鸟类栖息地的质量;生境类型Ⅱ增加常绿树种、小乔木、食源灌木和乡土草本植物的种植密度,减少对地被植物的收割干扰与枯落物清除,提高微景观异质性;生境类型Ⅲ增加配置具有速生特性的鸟类食源树种,适度提高乔灌层的高度、盖度和丰富度。 展开更多
关键词 鸟类多样性 温榆河−北运河生态廊道 取食集团 生境优化策略
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