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Femtosecond laser small incision lenticule extraction on binocularity for myopia with glasses-free 3D technique
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作者 Bing-Jie Chen Yu-Chen Fan Yong-Chuan Liao 《International Journal of Ophthalmology(English edition)》 2025年第1期125-131,共7页
AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic p... AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic patients(39 females and 11 males)with SMILE were enrolled in this prospective study.The glasses-free 3D technique was used to evaluate the binocular visual function in these subjects including static stereopsis,dynamic stereopsis,foveal suppression,and binocular balance point of signal to noise ratio(s/n ratio).All subjects received measurements in 1d before operation,and 1d,1wk,and 1mo postoperatively.RESULTS:Both static and dynamic stereopsis showed no significant difference after SMILE.The foveal suppression improved significantly 1wk and 1mo after SMILE(P=0.005 and P=0.007 respectively).The binocular balance point of signal to noise ratio showed a significant improvement 1d,1wk and 1mo after SMILE for both eyes(P<0.001 for each eye respectively).CONCLUSION:Glasses-free 3D technique can be used to evaluate the effect of SMILE on the binocular visual function in myopic patients perceptively,and SMILE can improve both foveal suppression and binocular imbalance in these patients. 展开更多
关键词 MYOPIA small incision lenticule extraction foveal suppression binocular imbalance glasses-free threedimensional technique
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Clinical observation of extraction-site incisional hernia after laparoscopic colorectal surgery 被引量:1
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作者 Bao-Hang Fan Ke-Li Zhong +3 位作者 Li-Jin Zhu Zhao Chen Fang Li Wen-Fei Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期710-716,共7页
BACKGROUND Laparoscopic colorectal cancer surgery increases the risk of incisional hernia(IH)at the tumor extraction site.AIM To investigate the incidence of IH at extraction sites following laparoscopic colo-rectal c... BACKGROUND Laparoscopic colorectal cancer surgery increases the risk of incisional hernia(IH)at the tumor extraction site.AIM To investigate the incidence of IH at extraction sites following laparoscopic colo-rectal cancer surgery and identify the risk factors for IH incidence.METHODS This study retrospectively analyzed the data of 1614 patients who underwent la-paroscopic radical colorectal cancer surgery with tumor extraction through the abdominal wall at our center between January 2017 and December 2022.Diffe-rences in the incidence of postoperative IH at different extraction sites and the risk factors for IH incidence were investigated.RESULTS Among the 1614 patients who underwent laparoscopic radical colorectal cancer surgery,303(18.8%),923(57.2%),171(10.6%),and 217(13.4%)tumors were ex-tracted through supraumbilical midline,infraumbilical midline,umbilical,and off-midline incisions.Of these,52 patients developed IH in the abdominal wall,with an incidence of 3.2%.The incidence of postoperative IH was significantly higher in the off-midline incision group(8.8%)than in the middle incision groups[the supraumbilical midline(2.6%),infraumbilical midline(2.2%),and umbilical incision(2.9%)groups](χ^(2)=24.985;P<0.05).Univariate analysis showed that IH occurrence was associated with age,obesity,sex,chronic cough,incision infection,and combined diabetes,anemia,and hypopro-teinemia(P<0.05).Similarly,multivariate analysis showed that off-midline incision,age,sex(female),obesity,incision infection,combined chronic cough,and hypoproteinemia were independent risk factors for IH at the site of laparoscopic colorectal cancer surgery(P<0.05).CONCLUSION The incidence of postoperative IH differs between extraction sites for laparoscopic colorectal cancer surgery.The infraumbilical midline incision is associated with a lower hernia rate and is thus a suitable tumor extraction site. 展开更多
关键词 incisional hernia LAPAROSCOPY Colorectal cancer incision infection
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Ten-year observation of corneal densitometry and associated factors following small incision lenticule extraction
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作者 Xiao-Song Han Fei Xia +4 位作者 Zhuo-Yi Chen Pei-Jun Yao Dong-Mei Yang Jing Zhao Xing-Tao Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期485-490,共6页
●AIM:To investigate the long-term changes of corneal densitometry(CD)and its contributing elements after small incision lenticule extraction(SMILE).●METHODS:Totally 31 eyes of 31 patients with mean spherical equival... ●AIM:To investigate the long-term changes of corneal densitometry(CD)and its contributing elements after small incision lenticule extraction(SMILE).●METHODS:Totally 31 eyes of 31 patients with mean spherical equivalent of-6.46±1.50 D and mean age 28.23±7.38y were enrolled.Full-scale examinations were conducted on all patients preoperatively and during followup.Visual acuity,manifest refraction,axial length,corneal thickness,corneal higher-order aberrations,and CD were evaluated.●RESULTS:All surgeries were completed successfully without complications or adverse events.Ten-year safety index was 1.17±0.20 and efficacy 1.04±0.28.CD value of 0–6 mm zones in central layer was statistically significantly lower 10y postoperatively,compared with preoperative values(0–2 mmΔ=-1.62,2–6 mmΔ=-1.24,P<0.01).There were no correlations between CD values and factors evaluated.●CONCLUSION:SMILE is a safe and efficient procedure for myopia on a long-term basis.CD values get lower 10y postoperatively,whose mechanism is to be further discussed. 展开更多
关键词 MYOPIA small incision lenticule extraction corneal densitometry
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Changes in posterior corneal elevation after small incision lenticule extraction for different myopic diopters
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作者 Xiao-Tong Sun Yang Zhang +5 位作者 Xiao-Kun Mei Nan-Nan Zheng Ling-Zhi Niu Xiao-Li Qu Ai-Ping Song Jian Zhuo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期491-498,共8页
●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were i... ●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were included in this retrospective study.Patients were allocated into three groups based on the preoperative spherical equivalent(SE):low myopia(SE≥-3.00 D),moderate myopia(-3.00 D>SE>-6.00 D)and high myopia(SE≤-6.00 D).Posterior corneal surfaces were measured by a Scheimpflug camera preoperatively and different postoperative times(1wk,1,3,6mo,and 1y).Posterior mean elevation(PME)at 25 predetermined points of 3 concentric circles(2-,4-,and 6-mm diameter)above the best fit sphere was analyzed.●RESULTS:All surgeries were completed uneventfully and no ectasia was found through the observation.The difference of myopia group was significant at the 2-mm ring at 1 and 3mo postoperatively(1mo:P=0.017;3mo:P=0.018).The effect of time onΔPME was statistically significant(2-mm ring:P=0.001;4-mm ring:P<0.001;6-mm ring:P<0.001).The effect of different corneal locations onΔPME was significant except 1wk postoperatively(1mo:P=0.000;3mo:P=0.000;6mo:P=0.001;1y:P=0.001).Posterior corneal stability was linearly correlated with SE,central corneal thickness,ablation depth,residual bed thickness,percent ablation depth and percent stromal bed thickness.●CONCLUSION:The posterior corneal surface changes dynamically after SMILE.No protrusion is observed on the posterior corneal surface in patients with different degrees of myopia within one year after surgery.SMILE has good stability,accuracy,safety and predictability. 展开更多
关键词 MYOPIA posterior corneal elevation corneal ectasia small incision lenticule extraction
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Influence of Surgical Incision Size and Interleukin 6 in the Occurrence of Postoperative Hyperalgesia in Lubumbashi/DR Congo
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作者 Christian Tshisuz-Nawej Nadine Kibwe +11 位作者 Felly Kazadi Berenice Kamba Ruffin Nyembo Cédric Sangwa Patient Kayoyo Eric Kasamba Sebastien Mbuyi Claude Mwamba-Mulumba Berthe Barahyga Adelin Muganza Iteke Fefe Willy Arung 《Open Journal of Anesthesiology》 2024年第11期232-247,共16页
Background: It appeared that the conjunction inflammation and nerve damage (caused by surgery) generate the hyperalgesic component. But the probability of predicting hyperalgesia from the size of the surgical incision... Background: It appeared that the conjunction inflammation and nerve damage (caused by surgery) generate the hyperalgesic component. But the probability of predicting hyperalgesia from the size of the surgical incision and/or the resulting inflammatory reaction is not well elucidated. This survey aims to study the influence of the size of the surgical incision and the resulting inflammatory reaction (interleukin 6 levels) in the occurrence of postoperative hyperalgesia in the population of Lubumbashi. Methods: The present study was descriptive cross-sectional. The data collection was prospective over 5 months, from February 1, 2024 to June 30, 2024. This study included any patient over the age of 18 who underwent surgery under general anesthesia. We used indirect signs to define hyperalgesia: higher (ENS > 6) and prolonged pain, postoperative overconsumption of morphine. Results: During our survey, we collected 48 operated patients who had severe postoperative pain, 16 of whom had hyperalgesia, i.e. a prevalence of hyperalgesia of 33.33%. The size of the incision most represented was between ≥20 and i.e. 62.50%. The type of surgery most affected by hyperalgesia was laparotomy. We observed an elevation of IL6 in 87.50% of patients. The largest elevation was 8.91 times the preoperative value and the smallest was 1.04 times. Pre- and postoperative IL6 levels were not associated with hyperalgesia (p = 0.265). Only the size of the surgical incision was associated with hyperalgesia (p = 0.04). Incision size values between [20 - 30] cm were those associated with hyperalgesia (p = 0.027). The model shows that making an incision greater than or equal to 20 cm increases the patient’s risk of developing hyperalgesia by more than 7.222 times and this is statistically significant (p = 0.004). Conclusion: According to this survey, the size of the surgical incision was associated with postoperative hyperalgesia and a size of more than 20 cm increases the patient’s risk of developing hyperalgesia by more than 7.222 times. 展开更多
关键词 Postoperative Hyperalgesia Prevalence Surgical incision Size Interleukin 6
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Micro-power negative pressure wound technique reduces risk of incision infection following loop ileostomy closure
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作者 Deng-Yong Xu Bing-Jun Bai +4 位作者 Lina Shan Hui-Yan Wei Deng-Feng Lin Ya Wang Da Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期186-195,共10页
BACKGROUND Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer.Incisional surgical site infection(SSI)is a common complic... BACKGROUND Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer.Incisional surgical site infection(SSI)is a common complication after ileostomy closure.AIM To evaluate the efficacy and safety of the micro-power negative pressure wound technique(MPNPWT)in preventing incisional SSI.METHODS This was a prospective,randomized controlled clinical trial conducted at a single center.A total of 101 consecutive patients who underwent ileostomy closure after rectal cancer surgery with a prophylactic ileostomy were enrolled from January 2019 to December 2021.Patients were randomly allocated into an MPNPWT group and a control group.The MPNPWT group underwent intermittent suturing of the surgical incision with 2-0 Prolene and was covered with a micro-power negative pressure dressing.The surgical outcomes were compared between the MPNPWT(n=50)and control(n=51)groups.Risk factors for incisional SSI were identified using logistic regression.RESULTS There were no differences in baseline characteristics between the MPNPWT(n=50)and control groups(n=51).The incisional SSI rate was significantly higher in the control group than in the MPNPWT group(15.7%vs 2.0%,P=0.031).However,MPNPWT did not affect other surgical outcomes,including intra-abdominal complications,operative time,and blood loss.Postoperative hospital stay length and hospitalization costs did not differ significantly between the two groups(P=0.069 and 0.843,respectively).None of the patients experienced adverse effects of MPNPWT,including skin allergy,dermatitis,and pain.MPNPWT also helped heal the infected incision.Our study indicated that MPNPWT was an independent protective factor[odds ratio(OR)=0.005,P=0.025)]and diabetes was a risk factor(OR=26.575,P=0.029)for incisional SSI.CONCLUSION MPNPWT is an effective and safe way to prevent incisional SSI after loop ileostomy closure. 展开更多
关键词 Micro-power negative pressure technique Ileostomy closure incisional surgical site infection Infection prevention Postoperative incision
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Endoscopic radial incision and cutting method for adult congenital duodenal webs:A case report
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作者 Hyun Deok Shin 《World Journal of Clinical Cases》 SCIE 2024年第18期3622-3628,共7页
BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniqu... BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniques have been developed and attempted for this disease.Endoscopic radial incision and cutting(RIC)techniques are reportedly very effective in benign anastomotic stricture.This case report highlights the effectiveness and safety of endoscopic RIC as a minimally invasive treatment for adult congenital duodenal webs.CASE SUMMARY A 23-year-old female patient with indigestion was referred to a tertiary hospital.The patient complained of postprandial fullness in the epigastric region.Previous physical examinations or blood tests indicated no abnormalities.Computed tomography revealed an eccentric broad-based delayed-enhancing mass-like lesion in the second portion of the duodenum.Endoscopy showed an enlarged gastric cavity and a significantly dilated duodenal bulb;a very small hole was observed in the distal part of the second portion,and scope passage was not possible.Gastrografin upper gastrointestinal series was performed,revealing an intraduodenal barium contrast-filled sac with a curvilinear narrow radiolucent rim,a typical"windsock"sign.Endoscopic RIC was performed on the duodenal web.The patient recovered uneventfully.Follow-up endoscopy showed a patent duodenal lumen without any residual stenosis.The patient reported complete resolution of symptoms at the 18-month follow-up.CONCLUSION Endoscopic RIC may be an effective treatment for congenital duodenal webs in adults. 展开更多
关键词 Congenital duodenal web Endoscopic treatment Radial incision and cutting method Surgery Case report
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Single incision laparoscopic surgery for hepatocellular carcinoma
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作者 Ilhan Karabicak Kadir Yildirim +1 位作者 Mahmut Fikret Gursel Zafer Malazgirt 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3078-3083,共6页
Single incision laparoscopic liver resection(SILLR)is the most recent develop-ment in the laparoscopic approach to the liver.SILLR for hepatocellular carci-noma(HCC)has developed much more slowly than multiport LLR.So... Single incision laparoscopic liver resection(SILLR)is the most recent develop-ment in the laparoscopic approach to the liver.SILLR for hepatocellular carci-noma(HCC)has developed much more slowly than multiport LLR.So far,195 patients completed SILLR for HCC.In this paper,we reviewed all published papers about SILLR for HCC and discussed the feasibility of the SILLR,peri and postoperative findings,tricks of patient selection and whether SILLR compromise the oncological principles. 展开更多
关键词 Single incision Laparoscopic liver surgery Liver resection Hepatocellular carcinoma Multiport laparoscopic liver resection
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Management Measures for Preventing Postoperative Incision Infections in General Surgery at Primary Hospitals
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作者 Jianqiang Yang 《Journal of Clinical and Nursing Research》 2024年第8期270-275,共6页
Objective:To analyze the management measures and effects of preventing postoperative incision infections in the general surgery department of primary hospitals.Methods:Forty-nine surgical patients with 11 healthcare w... Objective:To analyze the management measures and effects of preventing postoperative incision infections in the general surgery department of primary hospitals.Methods:Forty-nine surgical patients with 11 healthcare workers who were admitted to the general surgery department of the primary hospital between August 2021 and August 2022 were selected as the routine group for routine incision infection management.Forty-nine surgical patients with 11 healthcare workers admitted to the same department between September 2022 and September 2023 were selected as the prevention group for prophylactic management of postoperative incision infections.The incision infection rate,knowledge,attitude,and practice(KAP)scores,and management satisfaction of the patients as well as the management skill scores of healthcare workers were compared between the two groups.Results:The rate of postoperative incision infection in the prevention group was lower than that in the routine group;after implementing management measures,patients in the prevention group had higher KAP scores than those in the routine group;patients in the prevention group were more satisfied with the management than those in the routine group;and healthcare workers in the prevention group had higher scores than those in the routine group,with P<0.05 for the comparison between the groups.Conclusion:The implementation of preventive management for general surgery patients in primary hospitals can reduce the incidence of postoperative incision infection and improve the KAP of patients,with higher management satisfaction.It can also enhance the management skills of healthcare workers,thus improving their overall management level. 展开更多
关键词 Primary hospital General surgery Postoperative incision infection Management measures
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Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement
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作者 Chunyan Ji 《Journal of Clinical and Nursing Research》 2024年第2期196-200,共5页
Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected an... Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas. 展开更多
关键词 CATARACT Cataract ultrasonic emulsification Small incision cataract extracapsular extraction Therapeutic efficacy
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大兴安岭南段黄岗梁地区早白垩世正长花岗岩成因及构造启示:锆石U−Pb年龄、岩石地球化学和Sr−Nd−Pb同位素证据
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作者 顾玉超 陈仁义 +1 位作者 杜继宇 鞠楠 《地质通报》 北大核心 2025年第1期91-116,共26页
【研究目的】大兴安岭南段黄岗梁锡铁矿区及外围发育大面积花岗岩类,加强其成岩时代、岩石成因类型、成岩成矿物质来源等研究,有利于探究该区成岩与成矿关系和早白垩世碰撞造山机制。【研究方法】采集大兴安岭南段黄岗梁锡铁矿区及外围... 【研究目的】大兴安岭南段黄岗梁锡铁矿区及外围发育大面积花岗岩类,加强其成岩时代、岩石成因类型、成岩成矿物质来源等研究,有利于探究该区成岩与成矿关系和早白垩世碰撞造山机制。【研究方法】采集大兴安岭南段黄岗梁锡铁矿区及外围样品,进行岩相学、锆石U−Pb测年、岩石地球化学及Rb−Sr、Sm−Nd、Pb同位素研究。【研究结果】获得岩浆结晶年龄为141.9~139.1 Ma,较成矿年龄早约3 Ma,形成于早白垩世。岩石具有高硅、低铝、低镁、富钾少钠特征,为高钾钙碱性A型花岗岩。(^(87)Sr/^(86)Sr)_(i)和^(143)Nd/^(144)Nd值分别介于0.70031~0.70543和0.512572~0.512636之间,ε_(Nd)(t)值为0.07~1.18,Nd同位素模式年龄T_(DM2)为926~838 Ma。【结论】黄岗梁矽卡岩型锡铁矿床成岩物质于新元古代从亏损地幔分离,在上升侵位过程中受到地壳物质混染。大兴安岭南段地区在早白垩世经历了蒙古–鄂霍次克洋碰撞闭合伸展作用和古太平洋高角度俯冲作用叠加。 展开更多
关键词 Sr−Nd−Pb同位素 花岗岩 碰撞后伸展环境 锆石u−Pb年龄 黄岗梁地区 大兴安岭
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不同结构参数下的半U形地下空间烟气运动参数的机器学习预测
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作者 徐志胜 殷耀龙 +2 位作者 雷志强 陈诗仪 应后淋 《灾害学》 北大核心 2025年第1期67-73,共7页
结合火灾数值模拟(FDS)与机器学习方法,该文对半U形地下空间火灾时的烟气运动进行了深入分析。研究发现,在预测烟气回流长度及烟气最高温升方面,BP神经网络相比于支持向量机回归(SVR)展现了更高的精度,其决定系数超过了95%,而相对误差... 结合火灾数值模拟(FDS)与机器学习方法,该文对半U形地下空间火灾时的烟气运动进行了深入分析。研究发现,在预测烟气回流长度及烟气最高温升方面,BP神经网络相比于支持向量机回归(SVR)展现了更高的精度,其决定系数超过了95%,而相对误差仅集中在20%以内,显著优于SVR方法。通过shap值解释机器学习模型,并结合FDS数值模拟的结果,揭示坡高是影响烟气回流长度的决定性因素,且坡高的增大、宽度的减小或热释放速率增大均会缩短烟气回流。同时,热释放速率是影响烟气最高温升的主要因素,受坡高影响较大,而宽度的减小虽能在一定幅度上降低最高烟气温升,但效果并不显著。该研究拓展了地下空间火灾烟气运动参数的预测方法,为地下空间火灾动力学行为预测及通风排烟系统的优化设计贡献了创新性的方法。 展开更多
关键词 u形地下空间 机器学习 截面宽度 坡高 烟气回流长度 最高烟气温升
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基于嵌套U型的3D脑MRI配准网络
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作者 孙克雷 童波 潘宇 《兰州文理学院学报(自然科学版)》 2025年第1期53-58,共6页
针对传统的基于U-Net的图像配准网络对图像细节信息提取不够精确的问题,引入了一种嵌套的U型配准网络,在网络的每级编码解码阶段引入RSU-L的U型残差模块,并且在U型网络中的解码阶段每上采样一次均生成配准场,最后将配准场进行叠加得到... 针对传统的基于U-Net的图像配准网络对图像细节信息提取不够精确的问题,引入了一种嵌套的U型配准网络,在网络的每级编码解码阶段引入RSU-L的U型残差模块,并且在U型网络中的解码阶段每上采样一次均生成配准场,最后将配准场进行叠加得到最终的配准形变场.在公开数据集中,与传统的ANTs、Voxelmorph和最新的Transmorph网络相比,提出的嵌套U型网络在Dice系数上提升了1%~11%,增加了网络模型在图像配准任务上的精确度,对于临床诊断具有一定的帮助. 展开更多
关键词 图像配准 嵌套结构 u型网络 配准场融合 残差结构
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副矿物包裹体和信号采集时间对锆石U-Pb年龄和微量元素分析结果的影响
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作者 黄宇 钟世华 +5 位作者 李三忠 赵鸿 薛梓萌 郭广慧 刘嘉情 牛警徽 《地学前缘》 北大核心 2025年第1期388-400,共13页
锆石原位微区U-Pb定年和微量元素分析已成为当前地球科学领域常规的分析手段。然而,锆石微区分析结果的解译受到分析点选取、仪器稳定性和采集信号校正等诸多因素的影响,定量揭示这些因素如何影响锆石微区分析结果是准确探讨该结果地质... 锆石原位微区U-Pb定年和微量元素分析已成为当前地球科学领域常规的分析手段。然而,锆石微区分析结果的解译受到分析点选取、仪器稳定性和采集信号校正等诸多因素的影响,定量揭示这些因素如何影响锆石微区分析结果是准确探讨该结果地质意义的重要前提。本文以来自青海野马泉铁多金属矿床晚三叠世二长花岗斑岩岩体中的锆石为研究对象,开展了LA-ICP-MS锆石原位U-Pb定年和微量元素分析,以探究副矿物包裹体和信号采集时间对锆石微区分析结果产生的影响。研究结果显示,尽管信号采集时间较短时会得到较大的U-Pb定年误差,但它的改变并不会对U-Pb年龄和微量元素分析结果产生明显影响。对比含矿物包裹体和不含矿物包裹体的分析点可知,矿物包裹体的存在同样不会对定年结果产生明显干扰。然而,若选择的锆石分析位置含有磷灰石等副矿物包裹体,得到的分析数据会具有“轻稀土富集”的假象,从而造成诸多误判,如推断出错误的岩浆氧逸度特征等。因此,锆石微区分析前必须首先查明所分析的位置是否存在副矿物包裹体,而在探讨锆石微量元素数据的地质意义前必须将受到矿物包裹体混染的锆石数据予以剔除。 展开更多
关键词 LA-ICP-MS 锆石 u-PB定年 副矿物包裹体 信号采集时间
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东昆仑波洛尕熊金矿区石英闪长玢岩锆石U-Pb测年、岩石地球化学及地质意义
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作者 孔会磊 李青 +4 位作者 李金超 张江伟 南卡俄吾 国显正 贾群子 《西北地质》 北大核心 2025年第1期150-165,共16页
波洛尕熊金矿区位于青海东昆仑东段,矿区内石英闪长玢岩脉与金矿化带在空间上伴生产出。笔者通过锆石LA-ICP-MS U-Pb定年及地球化学研究,探讨了波洛尕熊石英闪长玢岩的岩浆源区和岩石成因、大地构造意义、形成时代与找矿意义。岩石地球... 波洛尕熊金矿区位于青海东昆仑东段,矿区内石英闪长玢岩脉与金矿化带在空间上伴生产出。笔者通过锆石LA-ICP-MS U-Pb定年及地球化学研究,探讨了波洛尕熊石英闪长玢岩的岩浆源区和岩石成因、大地构造意义、形成时代与找矿意义。岩石地球化学研究表明,石英闪长玢岩属准铝质钙碱性-高钾钙碱性系列岩石,富集大离子亲石元素、轻稀土元素和Pb,相对亏损高场强元素,基本不显示铕异常。Rb/Sr、Nb/Ta、Zr/Hf等特征反映闪长玢岩具有壳幔混合的源区特征。石英闪长玢岩LA−ICP−MS锆石U−Pb年龄为(226.6±1.6)Ma(MSWD=0.41),形成时代为印支期晚三叠世,为东昆仑造山带古特提斯构造岩浆演化的产物。综合东昆仑地区前人年代学数据及区域构造演化,认为波洛尕熊石英闪长玢岩为后碰撞伸展阶段地壳重熔的产物,东昆仑在约228 Ma就已全面进入后碰撞演化阶段。印支期中基性岩脉尤其是闪长玢岩脉经常与东昆仑地区金矿化在时空分布及成因上关系密切,在今后金矿找矿勘查中应高度重视。 展开更多
关键词 地球化学 锆石LA-ICP-MS u-Pb定年 后碰撞 石英闪长玢岩 波洛尕熊 东昆仑
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新疆东准噶尔晚古生代—中生代的剥露历史:来自裂变径迹和(U-Th)/He热年代学的约束
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作者 徐芹芹 赵磊 王艳楠 《地质学报》 北大核心 2025年第1期320-336,共17页
东准噶尔造山带(简称东准噶尔)是中亚造山带的重要组成部分,是造山带时空演化与造山作用方式研究的天然实验室。自古生代以来,东准噶尔经历了多阶段的构造演化,前人的研究多集中于古生代大地构造格局的恢复和构造演化模型的建立,对构造... 东准噶尔造山带(简称东准噶尔)是中亚造山带的重要组成部分,是造山带时空演化与造山作用方式研究的天然实验室。自古生代以来,东准噶尔经历了多阶段的构造演化,前人的研究多集中于古生代大地构造格局的恢复和构造演化模型的建立,对构造-热演化历史的解剖相对薄弱,尤其缺少晚古生代剥露历史的刻画。卡拉麦里山是东准噶尔造山带的重要构造地貌单元,揭示其隆升-剥露过程对于认识东准噶尔造山带的构造-热演化历史具有重要的意义。本文对卡拉麦里山东段的4件沉积岩样品进行了锆石(U-Th)/He、磷灰石裂变径迹与磷灰石(U-Th-Sm)/He低温热年代学分析,获得了该区晚古生代—中生代的隆升-剥露信息。热历史反演结果表明,东准噶尔经历了晚石炭世—早二叠世(330~290 Ma)、早二叠世晚期—中二叠世(285~260 Ma)、三叠纪(250~230 Ma)、早白垩世(135~115 Ma)4期快速剥露。第1期(330~290 Ma)剥露推测与额尔齐斯-斋桑洋在晚石炭世的闭合有关;第2期(285~260 Ma)剥露推测与晚古生代卡拉麦里构造带的右行走滑变形有关;第3期(250~230 Ma)剥露推测与羌塘地块和昆仑-柴达木地块碰撞的远程效应有关;第4期(135~115 Ma)剥露推测是北侧蒙古-鄂霍茨克洋的关闭和南侧羌塘地块与拉萨地块碰撞的联合作用的结果。 展开更多
关键词 磷灰石裂变径迹 锆石与磷灰石(u-Th)/He 剥露 晚古生代 东准噶尔
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北秦岭南召盆地太山庙组下部凝灰岩锆石U-Pb年龄及其地质意义
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作者 刘超 梁天 +5 位作者 杨文涛 陈浩 刘萧萧 安海花 李昕 马强分 《河南理工大学学报(自然科学版)》 CAS 北大核心 2025年第1期68-79,共12页
晚三叠世卡尼期全球古气候发生明显转变,全球降水量增加,海水温度上升了6~8℃,大量陆源碎屑物质输入海洋,导致海洋中出现碳酸盐生产危机。北秦岭南召盆地太山庙组可能记录了卡尼期洪水事件。目的为精确限定太山庙组沉积时代,凸显其地质... 晚三叠世卡尼期全球古气候发生明显转变,全球降水量增加,海水温度上升了6~8℃,大量陆源碎屑物质输入海洋,导致海洋中出现碳酸盐生产危机。北秦岭南召盆地太山庙组可能记录了卡尼期洪水事件。目的为精确限定太山庙组沉积时代,凸显其地质意义,方法采用激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)对太山庙组下部凝灰岩进行锆石U-Pb同位素定年分析。结果结果表明:凝灰岩锆石颗粒呈粒状、短柱状,无磨圆;阴极发光图像显示振荡环带结构明显;根据阴极发光图像和Th/U,认为太山庙组下部凝灰岩中18颗锆石均为火山来源,剔除轻稀土富集的锆石后,选择其中15颗锆石进行计算,得到其加权平均年龄为(241.4±1.3)Ma(1σ;MSWD=0.27),代表凝灰岩中锆石的结晶年龄;结合前人研究成果,计算出太山庙组下部平均沉积速率为20.6 m/Ma,太山庙组底界年龄约246 Ma,因此,太山庙组至少自中三叠世安尼期就开始沉积,至晚三叠世卡尼期末结束;根据南召盆地遗迹化石组合演化规律和植物孢粉变化,认为太山庙组沉积时期古气候发生了明显转变,由干旱炎热气候转变为温暖、湿润气候。结论研究结果对北秦岭南召盆地三叠纪地层划分产生了新认识,有助于研究探讨南召盆地对卡尼期洪水事件的沉积响应。 展开更多
关键词 卡尼期洪水幕 u-PB同位素定年 三叠纪 南召盆地 太山庙组 陆相沉积 火山凝灰岩
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普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响及校正方法
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作者 罗涛 王瀚林 +2 位作者 朱松柏 卿丽媛 胡兆初 《岩矿测试》 CAS 北大核心 2025年第1期51-62,共12页
磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基... 磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基体匹配磷灰石U-Pb定年矿物标样缺乏和标样中不可避免的普通铅是制约LA-ICP-MS高精度磷灰石U-Pb年龄分析的主要瓶颈。本文对比研究了标样中普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响,采用含普通铅的磷灰石MAD作外标直接开展U-Pb年龄校正,获得的被测样品年龄会产生显著的系统偏差(最大约6%);采用207Pb法或Tera-Wasserburg图解法先校正标样中普通铅,再利用校正后的数据进行元素分馏和仪器漂移校正则可获得准确的磷灰石U-Pb年龄,与推荐值偏差在2%以内。另一方面,为消除标样中普通铅对分析结果的影响,本文还采用水蒸气辅助激光剥蚀方法,实现以NIST612玻璃作为外标准确分析磷灰石U-Pb年龄,解决了磷灰石U-Pb定年微区分析高质量标样缺乏的难题。本研究通过对标样中普通铅进行预校正或采用非基体匹配分析,建立了高精度LA-ICP-MS磷灰石U-Pb定年新方法,将促进磷灰石U-Pb年代学在地球科学研究中的应用。 展开更多
关键词 激光剥蚀电感耦合等离子体质谱法 磷灰石 u-PB定年 普通铅校正 非基体匹配分析
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Learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy 被引量:15
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作者 Ming-Xin Pan Zhi-Wei Liang +5 位作者 Yuan Cheng Ze-Sheng Jiang Xiao-Ping Xu Kang-Hua Wang Hai-Yan Liu Yi Gao 《World Journal of Gastroenterology》 SCIE CAS 2013年第29期4786-4790,共5页
AIM: To investigate the learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy (SILC). METHODS: The clinical data of 180 consecutive transumbilical suture-suspension SILCs perf... AIM: To investigate the learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy (SILC). METHODS: The clinical data of 180 consecutive transumbilical suture-suspension SILCs performed by a team in our department during the period from August 2009 to March 2011 were retrospectively analyzed. Patients were divided into nine groups according to operation dates, and each group included 20 patients operated on consecutively in each time period. The surgical outcome was assessed by comparing operation time, blood loss during operation, and complications between groups in order to evaluate the improvement in technique.RESULTS: A total of 180 SILCs were successfully performed by five doctors. The average operation time was 53.58 ± 30.08 min (range: 20.00-160.00 min) and average blood loss was 12.70 ± 11.60 mL (range: 0.00-100.00 mL). None of the patients were converted to laparotomy or multi-port laparoscopic cholecystectomy. There were no major complications such as hemorrhage or biliary system injury during surgery. Eight postoperative complications occurred mainly in the first three groups (n = 6), and included ecchymosis around the umbilical incision (n = 7) which resolved without special treatment, and one case of delayed bile leakage in group 8, which was treated by ultrasound-guided puncture and drainage. There were no differences in intraoperative blood loss, postoperative complications and length of postoperative hospital stay among the groups. Bonferroni's test showed that the operation time in group 1 was significantly longer than that in the other groups (F = 7.257, P = 0.000). The majority of patients in each group were discharged within 2 d, with an average postoperative hospital stay of 1.9 ± 1.2 d. CONCLUSION: Following scientific principles and standard procedures, a team experienced in multi-port laparoscopic cholecystectomy can master the technique of SILC after 20 cases. 展开更多
关键词 Single incision LAPAROSCOPIC surgery CHOLECYSTECTOMY Learning curve Suture-suspension
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Single-incision laparoscopic cholecystectomy:Single institution experience and literature review 被引量:24
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作者 Yasumitsu Hirano Toru Watanabe +4 位作者 Tsuneyuki Uchida Shuhei Yoshida Kanae Tawaraya Hideaki Kato Osamu Hosokawa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第2期270-274,共5页
Single-incision laparoscopic surgery is a rapidly evolving field as a bridge between traditional laparoscopic surgery and natural orifice transluminal endoscopic surgery.We report one of the initial clinical experienc... Single-incision laparoscopic surgery is a rapidly evolving field as a bridge between traditional laparoscopic surgery and natural orifice transluminal endoscopic surgery.We report one of the initial clinical experiences in Japan with this new technique.Four cases of gallbladder diseases were selected for this new technique.A single curved intra-umbilical 25-mm incision was made by pulling out the umbilicus.A 12-mm trocar was placed through an open approach,and the abdominal cavity was explored with a 10-mm semiflexible laparoscope.Two 5-mm ports were inserted laterally from the laparoscope port.A 2-mm mini-loop retractor was inserted to retract the fundus of the gallbladder.Dissection was performed using an electric cautery hook and an Endograsper roticulator.There were two women and two men with a mean age of 50.5 years(range:40-61 years).All procedures were completed successfully without any perioperative complications.In all cases,there was no need to extend the skin incision.Average operative time was 88.8 min.Postoperative follow-up didnot reveal any umbili-cal wound complication.Single-incision laparoscopic cholecystectomy is feasible and a promising alternative method as scarless abdominal surgery for the treatment of some patients with gallbladder disease. 展开更多
关键词 Laparoscopic Cholecystectomy incision Single-incision laparoscopic cholecystectomy Singleincision laparoscopic surgery Single-incision endoscopic surgery Minimally invasive surgery
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