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Comprehensive application of modern technologies in precise liver resection 被引量:29
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作者 Nian-Song Qian Yong-Hui Liao +2 位作者 Shou-Wang Cai Vikram Raut Jia-Hong Dong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第3期244-250,共7页
BACKGROUND: Liver surgery has gone through the phases of wedge liver resection, regular resection of hepatic lobes, irregular and local resection, extracorporeal hepatectomy, hemi-extracorporeal hepatectomy and Da Vin... BACKGROUND: Liver surgery has gone through the phases of wedge liver resection, regular resection of hepatic lobes, irregular and local resection, extracorporeal hepatectomy, hemi-extracorporeal hepatectomy and Da Vinci surgical system-assisted hepatectomy. Taking advantage of modern technologies, liver surgery is stepping into an age of precise liver resection. This review aimed to analyze the comprehensive application of modern technologies in precise liver resection. DATA SOURCE: PubMed search was carried out for English-language articles relevant to precise liver resection, liver anatomy, hepatic blood inflow blockage, parenchyma transection, and down-staging treatment. RESULTS: The 3D image system can imitate the liver operation procedures, conduct risk assessment, help to identify the operation feasibility and confirm the operation scheme. In addition, some techniques including puncture and injection of methylene blue into the target Glisson sheath help to precisely determine the resection. Alternative methods such as Pringle maneuver are helpful for hepatic blood inflow blockage in precise liver resection. Moreover, the use of exquisite equipment for liver parenchyma transection, such as cavitron ultrasonic surgical aspirator, ultrasonic scalpel, Ligasure and Tissue Link is also helpful to reduce hemorrhage in liver resection, or even operate exsanguinous liver resection without blocking hepatic blood flow. Furthermore, various down-staging therapies including transcatheter arterial chemoembolization and radio-frequency ablation were appropriate for unresectable cancer, which reverse the advanced tumor back to early phase by local or systemic treatment so that hepatectomy or liver transplantation is possible.CONCLUSIONS: Modern technologies mentioned in this paper are the key tool for achieving precise liver resection and can effectively lead to maximum preservation of anatomical structural integrity and functions of the remnant liver. In addition, large randomized trials are needed to evaluate the usefuln 展开更多
关键词 precise liver resection ANATOMY parenchyma transection down-staging treatment
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骨搬运治疗胫骨骨缺损合并软组织缺损的疗效及影响因素 被引量:12
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作者 谢伟文 谌业光 张伟才 《局解手术学杂志》 2018年第9期650-654,共5页
目的探讨骨搬运治疗胫骨骨缺损合并软组织缺损的疗效及发生并发症的影响因素。方法回顾性分析我院2014年3月至2017年5月30例骨搬运治疗胫骨骨缺损合并软组织缺损患者的临床资料,其中20例为创伤性慢性骨髓炎致下肢长骨骨缺损患者,10例为... 目的探讨骨搬运治疗胫骨骨缺损合并软组织缺损的疗效及发生并发症的影响因素。方法回顾性分析我院2014年3月至2017年5月30例骨搬运治疗胫骨骨缺损合并软组织缺损患者的临床资料,其中20例为创伤性慢性骨髓炎致下肢长骨骨缺损患者,10例为创伤后非感染性下肢长骨骨缺损患者。观察所有患者的治疗效果及并发症发生情况,并分析疗效及安全性的影响因素。结果 30例患者均获得随访,随访时间大于8个月,平均16. 9个月。治疗周期为8~15个月,平均12. 3个月。术后骨搬运完成,外固定架使用时间为术后220 d,皮肤均在骨搬运过程中自然愈合,术后均给予功能锻炼,6个月后愈合。在治疗过程中,出现骨不愈合18例,软组织嵌顿12例,接触面积不足6例,对线不良8例。单因素分析结果显示,软组织调节差是骨搬运治疗过程中断端软组织嵌顿的影响因素,感染是断端骨不愈合的影响因素,股骨骨缺损是骨搬运过程中断端对线不良的影响因素。结论胫骨骨缺损合并软组织缺损应用骨搬运技术后软组织嵌顿、断端骨不愈合、对线不良等并发症发生率较高,虽然最终均可通过后期的治疗达到愈合,但是影响康复时间,在治疗过程中软组织修复差、感染、股骨骨缺损等均应引起骨科医生的重视。 展开更多
关键词 骨搬运 胫骨 骨缺损 软组织
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Antidiastole Value of Three-dimensional Ultrasonography and Power Doppler between Uterine Parenchyma Lumps and Endometrial Cancer:A Retrospective Study 被引量:12
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作者 Yan ZHANG Jing CHEN +1 位作者 Zeng ZHEN Xiao-yan XU 《Current Medical Science》 SCIE CAS 2019年第5期816-819,共4页
Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensi... Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensional(3D)power Doppler ultrasonography angiography(PDA)between endometrial cancer and uterine parenchyma lumps.The data of the blood flow indices in 3D-PDA including the vascularization index(VI),flow index(FI),and vascularization flow index(VFI)in 40 patients with endometrial cancer and 41 patients with uterine parenchyma lumps(endometrial polyps and submucosal myomas)were retrospectively analysed and compared utilizing Virtual Organ Computer-aided AnaLysis(VOCAL)software.The results showed that all the blood flow parameters(VI,FI,VFI)were significantly higher in women with endometrial cancer than in those with uterine parenchyma lumps(P<0.001).The area under the curve of ROC of VI,FI,and VFI was 0.98,0.84,and 0.97,respectively.Thus,the best predictor of endometrial carcinoma was VI with a sensitivity of 97.0% and a specificity of 91.0%.The optimal cutoff value of VI was 4.06%.Our data demonstrated that all of the blood flow signal parameters(including VI,FI,and VFI)in 3D power Doppler ultrasonography had significant antidiastole values between endometrial cancer and uterine parenchyma lumps to assist clinicians in properly diagnosing patients. 展开更多
关键词 power DOPPLER three-dimensional ultrasound UTERINE parenchyma lump ENDOMETRIAL CARCINOMA BLOOD flow signal parameter
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幕上脑实质内室管膜瘤14例临床分析 被引量:9
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作者 陈文裕 冯珂珂 +2 位作者 汪寿生 梁恩和 杨玉山 《中华神经外科杂志》 CSCD 北大核心 2011年第3期300-302,共3页
目的 探讨幕上脑实质内室管膜瘤的临床特点、影像学表现、治疗和预后.方法 对经手术后病理证实的14例幕上脑实质内室管膜瘤进行临床分析.其中室管膜瘤10例,恶性室管膜瘤4例.肿瘤位于额叶4例,顶叶8例,枕叶2例.肿瘤呈完全实质性者3例,囊... 目的 探讨幕上脑实质内室管膜瘤的临床特点、影像学表现、治疗和预后.方法 对经手术后病理证实的14例幕上脑实质内室管膜瘤进行临床分析.其中室管膜瘤10例,恶性室管膜瘤4例.肿瘤位于额叶4例,顶叶8例,枕叶2例.肿瘤呈完全实质性者3例,囊性变者11例.结果 全部病例均手术切除.全切除10例,次全切除4例.随访时间3个月-4年.3例患者复发后行二次手术,其中1例患者手术后4个月死亡;1例患者复发后拒绝再次手术后6个月死亡,12例患者目前仍存活.结论 幕上脑实质内室管膜瘤术前诊断较困难,应注意与其他肿瘤相鉴别.手术全切除效果良好,神经导航辅助下的显微手术有助于手术全切除. 展开更多
关键词 脑实质 室管膜瘤 外科手术 全切除
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高地钩叶藤与钩叶藤组织比量的变异研究 被引量:9
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作者 刘杏娥 吴明山 +5 位作者 汪佑宏 费本华 田根林 徐斌 武恒 涂道伍 《安徽农业大学学报》 CAS CSCD 北大核心 2015年第1期27-30,共4页
为合理开发利用棕榈藤资源,以高地钩叶藤和钩叶藤为研究对象,采用生物解剖学方法,系统分析各组织比量在径向和轴向的变化规律。结果表明,高地钩叶藤和钩叶藤薄壁组织、后生木质部大导管、纤维及筛管比量分别为59.6%和50.2%、15.9%和16.4... 为合理开发利用棕榈藤资源,以高地钩叶藤和钩叶藤为研究对象,采用生物解剖学方法,系统分析各组织比量在径向和轴向的变化规律。结果表明,高地钩叶藤和钩叶藤薄壁组织、后生木质部大导管、纤维及筛管比量分别为59.6%和50.2%、15.9%和16.4%、19.6%和28.9%、4.9%和4.5%,其中薄壁组织比量高地钩叶藤比钩叶藤高18.7%,纤维比量低32.2%,经F检验差异在0.05、0.01水平上分别达到显著和极显著。径向由外向内,薄壁组织比量呈增大趋势,后生木质部大导管比量、纤维比量和筛管比量呈减小趋势。随着轴向高度的增加,高地钩叶藤薄壁组织比量、钩叶藤筛管比量先增大后减小,钩叶藤薄壁组织比量、高地钩叶藤后生木质部大导管比量不断增加,高地钩叶藤和钩叶藤纤维比量呈下降趋势。 展开更多
关键词 高地钩叶藤 钩叶藤 组织比量 薄壁组织 纤维 导管 筛管
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An automated pulmonary parenchyma segmentation method based on an improved region growing algorithm in PET-CT imaging 被引量:6
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作者 Juanjuan ZHAO Guohua JI +2 位作者 Xiaohong HAN Yan QIANG Xiaolei LIAO 《Frontiers of Computer Science》 SCIE EI CSCD 2016年第1期189-200,共12页
To address the incomplete problem in pulmonary parenchyma segmentation based on the traditional methods, a novel automated segmentation method based on an eight- neighbor region growing algorithm with left-right scann... To address the incomplete problem in pulmonary parenchyma segmentation based on the traditional methods, a novel automated segmentation method based on an eight- neighbor region growing algorithm with left-right scanning and four-corner rotating and scanning is proposed in this pa- per. The proposed method consists of four main stages: image binarization, rough segmentation of lung, image denoising and lung contour refining. First, the binarization of images is done and the regions of interest are extracted. After that, the rough segmentation of lung is performed through a general region growing method. Then the improved eight-neighbor region growing is used to remove noise for the upper, mid- dle, and bottom region of lung. Finally, corrosion and ex- pansion operations are utilized to smooth the lung boundary. The proposed method was validated on chest positron emis- sion tomography-computed tomography (PET-CT) data of 30 cases from a hospital in Shanxi, China. Experimental results show that our method can achieve an average volume overlap ratio of 96.21 ± 0.39% with the manual segmentation results. Compared with the existing methods, the proposed algorithm segments the lung in PET-CT images more efficiently and ac- curately. 展开更多
关键词 pulmonary parenchyma segmentation bot-tom region of lung image binarization iterative threshold seeded region growing four-corner rotating and scanning denoising contour refining PET-CT
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毛竹薄壁细胞组分分布及取向显微成像研究 被引量:8
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作者 冯龙 孙存举 +4 位作者 毕文思 任珍珍 刘杏娥 江泽慧 马建锋 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第9期2957-2961,共5页
薄壁细胞是竹材基本组织中的主要细胞类型起到填充及淀粉贮存作用,是竹材中重要的力学承载单元之一。采用共聚焦荧光显微技术对解离后的竹材薄壁细胞形态进行成像观察,透射电子显微镜成像发现薄壁细胞次生壁呈现宽窄交替的同心层状结构... 薄壁细胞是竹材基本组织中的主要细胞类型起到填充及淀粉贮存作用,是竹材中重要的力学承载单元之一。采用共聚焦荧光显微技术对解离后的竹材薄壁细胞形态进行成像观察,透射电子显微镜成像发现薄壁细胞次生壁呈现宽窄交替的同心层状结构,且单层厚度在0.2~0.3μm。在此基础上利用532 nm共聚焦显微拉曼光谱成像技术原位状态下研究竹材薄壁细胞壁中木质素、纤维素区域化学,通过C—H伸缩振动(2789~3000 cm^-1)特征峰峰高拉曼成像成功的区分出薄壁细胞复合胞间层以及次生壁,由于空间分辨率限制无法对薄壁细胞次生壁亚层进行区分。通过对薄壁细胞拉曼光谱380 cm^-1(吡喃环C—C—C对称弯曲振动)和1600 cm^-1(木质素苯环伸缩振动)特征峰成像发现其次生壁中纤维素具有明显的区域选择性,而木质素具有明显的区域选择性,主要汇聚于复合胞间层及次生壁内层。与木质素共轭相联的松柏醛/芥子醛,以酯键和醚键与木质素和半纤维素相联的对羟基肉桂酸类与木质素分布规律类似。采用偏振光拉曼成像阐明纤维素微纤丝在薄壁细胞与纤维细胞各亚层中的空间取向差异,拉曼强度比值表明相对于纤维细胞宽层,纤维细胞窄层及薄壁细胞次生壁中纤维素分子更加趋近垂直于细胞轴向,也即是大的微纤丝角。研究结果加深了对毛竹薄壁细胞结构、细胞壁区域化学及分子取向特性的理解,能够为高效精准利用竹材提供重要的理论指导。 展开更多
关键词 毛竹 薄壁细胞 微纤丝空间取向 组分分布 共聚焦显微拉曼光谱
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Totally laparoscopic left hepatectomy using the Torsional Ultrasonic Scalpel 被引量:5
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作者 Georgios C Sotiropoulos Paraskevas Stamopoulos +3 位作者 Petros Charalampoudis Ernesto P Molmenti Athanasios Voutsarakis Gregory Kouraklis 《World Journal of Gastroenterology》 SCIE CAS 2013年第35期5929-5932,共4页
Minimal invasive techniques have allowed for major surgical advances.We report our initial experience of performing total laparoscopic left hepatectomy(segmentsⅡ-Ⅳ)with the Lotus(laparoscopic operation by torsional ... Minimal invasive techniques have allowed for major surgical advances.We report our initial experience of performing total laparoscopic left hepatectomy(segmentsⅡ-Ⅳ)with the Lotus(laparoscopic operation by torsional ultrasound)Ultrasonic Scalpel.The perioperative and postoperative courses of the young female patient were uneventful and she is in a good general condition without complaints 18 mo after surgery.To the best of our knowledge,this is the first total laparoscopic hemihepatectomy to be performed in Greece,as well as the first laparoscopic liver resection using Lotus shears. 展开更多
关键词 LAPAROSCOPIC SURGERY LIVER resectionMinimally invasive SURGERY Hepatectomy Bloodless SURGERY ULTRASONIC SCALPEL ULTRASONIC dissector parenchyma transection LIVER adenoma Focal nodular hyperplasia
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Protophyllocladoxylon jingyuanense sp.nov.,a Gymnospermous Wood of the Serpukhovian(Late Mississippian) from Gansu,Northwest China 被引量:5
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作者 ZHANG Yi WANG Jun +1 位作者 LIU Lujun LI Nan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第2期257-268,共12页
A new species of gymnospermous fossil wood, Protophyllocladoxylon jingyuanense sp. nov., is described from the lower part of the Tsingyuan Formation (Serpukhovian/Late Mississippian), near the coal mine of Ciyao, Ga... A new species of gymnospermous fossil wood, Protophyllocladoxylon jingyuanense sp. nov., is described from the lower part of the Tsingyuan Formation (Serpukhovian/Late Mississippian), near the coal mine of Ciyao, Gansu, northwestern China. The specimen is preserved only in silicified secondary xylem, while growth rings are absent. Pits in radial tracheidal walls are araucaroid in type, uniseriate, occasionally biseriate. Xylem rays are homogeneous, uniseriate, occasionally biseriate. Cross-field pits are simple, large, one to two in number. Axial parenchyma is absent. The anatomical characters and geographic distribution of Protophyllocladoxylon woods through geological ages are documented. Those species with axial parenchyma and without growth rings live in warm climate, whereas the species without axial parenchyma and with growth rings are present either in warm or cool climate. The ideal living climate for Protophyllocladoxylon woods is warm and wet. Our new species, as a fossil wood of Early Carboniferous, is likely the earliest known species of Protophyllocladoxylon. 展开更多
关键词 Protophyllocladoxylonjingyuanense growth rings axial parenchyma climate
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软组织海绵状血管瘤的超声诊断研究 被引量:7
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作者 牛卫东 李洪福 门光明 《医学影像学杂志》 2010年第9期1358-1360,共3页
目的:探讨软组织海绵状血管瘤的超声表现及其与病理变化的相关性。方法:应用高频彩色多普勒超声诊断仪观察软组织海绵状血管瘤超声表现,采用超声压力试验观察其前后的声像图变化。结果:31例海绵状血管瘤均表现为网状结构。压力试验时病... 目的:探讨软组织海绵状血管瘤的超声表现及其与病理变化的相关性。方法:应用高频彩色多普勒超声诊断仪观察软组织海绵状血管瘤超声表现,采用超声压力试验观察其前后的声像图变化。结果:31例海绵状血管瘤均表现为网状结构。压力试验时病变压缩率为30%~45%,回声相对增强,同一网眼内血流信号红蓝交替,频谱时相相反。结论:超声压力试验是诊断软组织海绵状血管瘤的一种便捷、有效的方法,其超声表现具有特征性,超声可作为软组织海绵状血管瘤的首选影像学检查方法。 展开更多
关键词 软组织 海绵状血管瘤 多普勒 超声
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Primary parenchymal squamous cell carcinoma of the kidney:A case report
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作者 Zhi-Hui Zheng Bo Shao +4 位作者 Chao-Min Xu Ke Wang Jia-Zhu Wen Li-Kang Luo Jia-Cheng Guan 《World Journal of Clinical Cases》 SCIE 2025年第4期34-40,共7页
BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The pat... BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross hematuria.SCC antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated calculi.The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection.Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and ureter.The pathological stage was Pt3aN1M0.Four months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena cava.The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.CONCLUSION We report a case of primary SCC of the renal parenchyma,a rare renal malignancy.The clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis challenging.According to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered. 展开更多
关键词 Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report
中亚热带喀斯特常绿落叶阔叶混交林典型树种的木质部解剖与功能特征分析 被引量:6
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作者 倪鸣源 ARITSARA Amy Ny Aina +4 位作者 王永强 黄冬柳 项伟 万春燕 朱师丹 《植物生态学报》 CAS CSCD 北大核心 2021年第4期394-403,共10页
树木木质部主要由导管、纤维和薄壁组织组成,分别具有运输、支撑和贮存的生理功能。由于木质部空间限制,一种组织比例的增加会导致其他组织比例的降低,因而可能表现出权衡关系。分析木质部组织比例和权衡关系有助于了解植物的生理生态... 树木木质部主要由导管、纤维和薄壁组织组成,分别具有运输、支撑和贮存的生理功能。由于木质部空间限制,一种组织比例的增加会导致其他组织比例的降低,因而可能表现出权衡关系。分析木质部组织比例和权衡关系有助于了解植物的生理生态适应性。该研究选择中亚热带喀斯特常绿落叶阔叶混交林21种典型树种(10种落叶树种, 11种常绿树种),测定枝条木质部各组织比例,计算水力相关指标并分析性状之间的相关性。结果表明:(1)与全球木质部解剖数据对比分析,喀斯特树种木质部趋向具有较高比例的薄壁组织;(2)喀斯特树种导管组织比例与薄壁和纤维组织比例之间没有显著的相关性,但是薄壁和纤维组织比例之间有显著的权衡关系;(3)常绿和落叶树种的木质部水力运输安全性(导管壁加固系数)和效率性(理论导水率)均具有显著的权衡关系,但是这两个类群线性回归的截距存在显著差异,即在相同的理论导水率条件下,落叶树种比常绿树种具有较高的导管壁加固系数(安全性),可能与常绿树种具有更多的轴向薄壁组织有关。喀斯特树种木质部解剖特征表明薄壁组织的贮存功能对喀斯特树种(尤其是常绿树种)的干旱适应具有重要作用。 展开更多
关键词 导管组织 薄壁组织 纤维组织 导管壁加固系数 理论导水率 权衡
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黄藤材薄壁细胞木质素分布的可见光谱分析 被引量:6
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作者 汪佑宏 刘杏娥 +4 位作者 江泽慧 费本华 周旭 张令峰 高龙芽 《南京林业大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第6期140-142,共3页
以我国特有的黄藤为研究对象,运用可见光显微分光光度计,对不同生长时期黄藤材薄壁细胞及细胞壁微区木质素含量和分布进行研究。结果表明:随着黄藤材藤龄的增大,薄壁细胞次生壁中紫丁香基木质素含量不断增大,紫丁香基木质素和愈疮木基... 以我国特有的黄藤为研究对象,运用可见光显微分光光度计,对不同生长时期黄藤材薄壁细胞及细胞壁微区木质素含量和分布进行研究。结果表明:随着黄藤材藤龄的增大,薄壁细胞次生壁中紫丁香基木质素含量不断增大,紫丁香基木质素和愈疮木基木质素总量呈"降—升—降"的变化趋势。薄壁细胞角隅处木质素含量高于次生壁,薄壁细胞壁各微区木质素含量均为胞间层较高,初生壁次之,次生壁最少。 展开更多
关键词 黄藤 可见光 薄壁细胞 木质化
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幕上脑实质室管膜瘤25例临床分析 被引量:5
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作者 简志宏 刘仁忠 +1 位作者 陈谦学 王国安 《肿瘤防治研究》 CAS CSCD 北大核心 2005年第12期785-786,共2页
目的探讨幕上脑实质室管膜瘤的临床、治疗和预后特点。方法对手术后经病理证实幕上脑实质室管膜瘤25例进行临床分析。室管膜瘤16例,室管膜下瘤2例,恶性室管膜瘤7例。肿瘤位于额叶8例,顶叶14例,枕叶3例。肿瘤呈完全实质性者6例,囊性变者1... 目的探讨幕上脑实质室管膜瘤的临床、治疗和预后特点。方法对手术后经病理证实幕上脑实质室管膜瘤25例进行临床分析。室管膜瘤16例,室管膜下瘤2例,恶性室管膜瘤7例。肿瘤位于额叶8例,顶叶14例,枕叶3例。肿瘤呈完全实质性者6例,囊性变者19例。结果全部病例均手术切除。全切除20例,次全切除5例。随访时间5月~5年者8例,5~10年者14例,10年以上者2例。死亡6例。3年以上存活者17例,其中5年存活者12例,10年存活者2例。结论对于分化良好的幕上脑实质室管膜瘤手术全切除可达到治愈目的,对于部分切除和恶性室管膜瘤手术应尽量切除并行放疗。 展开更多
关键词 脑实质 室管膜瘤 手术 预后
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竹材薄壁组织拉伸性能及其变异规律的研究 被引量:5
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作者 王福利 王献轲 +3 位作者 周佳硕 谢浩 许费扬 邵卓平 《北京林业大学学报》 CAS CSCD 北大核心 2020年第11期130-137,共8页
【目的】从力学角度看,竹材的薄壁组织扮演基体的角色,而因其几何形貌的限制,目前针对薄壁组织开展的力学方面的相关研究较少。探索薄壁组织的力学性能,尤其是基体材料属性的赋值,对竹材精细化仿真模型的建立起到关键作用,进而提高模拟... 【目的】从力学角度看,竹材的薄壁组织扮演基体的角色,而因其几何形貌的限制,目前针对薄壁组织开展的力学方面的相关研究较少。探索薄壁组织的力学性能,尤其是基体材料属性的赋值,对竹材精细化仿真模型的建立起到关键作用,进而提高模拟分析结果的准确性。【方法】以毛竹材为研究对象,7组试样取自同一竹秆不同高度处节间,软化后切厚度为30和80μm的弦切片,其中厚度为30μm的切片用于测试薄壁细胞形态参数,厚度为80μm的切片用于制作有效试验段仅含薄壁组织的拉伸试样,并在力学试验机上结合光学引伸计完成竹材薄壁组织的拉伸试验,计算分析其抗拉强度、弹性模量和失效应变。【结果】竹材薄壁细胞长、宽、腔径和双壁厚在竹秆高度方向上无明显的变异规律;薄壁组织的平均抗拉强度为13.08 MPa,抗拉弹性模量为830.86 MPa,失效应变为1.98%,三者在竹秆高度上的变异规律均不明显;竹材薄壁组织拉伸性能与薄壁细胞形态之间的线性相关性较低。对薄壁组织拉伸失效断口的分析表明其拉伸失效的实质是胞间层分离与细胞壁断裂,本试验采用的毛竹材薄壁组织的平均抗拉强度在13.08~34.82 MPa之间。【结论】试验方法与结果均可靠,试验结果将为全面而深入地了解竹材力学性能及其数学模型的建立提供重要的参考价值,另外本试验方法将为植物材料力学性能的相关研究提供参考。然而,为提高测量结果的准确性还需进一步的深入研究,竹材薄壁细胞组织构造在竹秆高度方向上的变异规律与其力学性能之间的关系仍需探索。 展开更多
关键词 竹材 薄壁组织 细胞形态 拉伸性能 失效机制
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黄藤发育过程中组织比量的变化 被引量:5
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作者 汪佑宏 刘杏娥 +3 位作者 江泽慧 费本华 田根林 任海青 《东北林业大学学报》 CAS CSCD 北大核心 2010年第5期51-53,共3页
以我国特有的黄藤为研究对象,采用生物解剖学方法,系统分析了各组织比量与生长发育规律之间的关系。结果表明:轴向上薄壁组织比量为71.0%~77.3%,平均值为72.6%,径向由内向外呈降低的变化趋势。后生木质部轴向上大导管比量为8.3%~12.4%... 以我国特有的黄藤为研究对象,采用生物解剖学方法,系统分析了各组织比量与生长发育规律之间的关系。结果表明:轴向上薄壁组织比量为71.0%~77.3%,平均值为72.6%,径向由内向外呈降低的变化趋势。后生木质部轴向上大导管比量为8.3%~12.4%,平均值为10.6%,藤茎外部最低。轴向上纤维比量为8.2%~10.9%,平均值为10.5%;径向上纤维比量由内向外呈增大的变化趋势。韧皮部筛管比量平均值为3.5%,原生木质部小导管比量平均值为2.8%。 展开更多
关键词 黄藤 组织比量 薄壁组织 纤维 导管
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某车型薄壁化保险杠的Moldflow分析 被引量:5
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作者 程健 刘凯 黄家奇 《汽车实用技术》 2018年第6期102-104,共3页
利用Moldflow从熔体流动前沿温度、V/P转换压力分布及锁模力方面仿真分析2.5mm壁厚保险杠成型工艺制定的可行性,并分析了熔接痕、气穴、翘曲几种常见缺陷产生的原因及解决措施。结果说明,薄壁化保险杠已满足生产量产条件。
关键词 保险杠 薄壁 MOLDFLOW
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Digital radiography of crush thoracic trauma in the Sichuan earthquake 被引量:2
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作者 Zhi-Hui Dong Heng Shao +5 位作者 Tian-Wu Chen Zhi-Gang Chu Wen Deng Si-Shi Tang Jing Chen Zhi-Gang Yang 《World Journal of Radiology》 CAS 2011年第11期273-278,共6页
AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered cru... AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered crush thoracic trauma in the Sichuan earthquake.Patient age ranged from 0.5 to 103 years.CDR was performed between May 12,2008 and June 7,2008.We looked for injury to the thoracic cage,pulmonary parenchyma and the pleura.obtained in 349 patients,the remaining 423 patients underwent only AP CDR.Thoracic cage fractures,pulmonary contusion and pleural injuries were noted in 331(42.9%;95% CI:39.4%-46.4%),67 and 135 patients,respectively.Of the 256 patients with rib fractures,the mean number of fractured ribs per patient was 3.Rib fractures were mostly distributed from the 3rd through to the 8th ribs and the vast majority involved posterior and lateral locations along the rib.Rib fractures had a significant positive association with non-rib thoracic fractures,pulmonary contusion and pleural injuries(P < 0.001).The number of rib fractures and pulmonary contusions were significant factors associated with patient death.CONCLUSION:Earthquake-related crush thoracic trauma has the potential for multiple fractures.The high number of fractured ribs and pulmonary contusions were significant factors which needed appropriate medical treatment. 展开更多
关键词 Earthquake PLEURA Pulmonary parenchyma RADIOGRAPHY THORACIC TRAUMA
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Ventricular system-unrelated cerebellar ependymoma:A case report
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作者 Chao-Ge Yang Rui-Feng Xue +3 位作者 Lu-Xia Yang Xiao-Lin Jieda Wei Xiang Jie Zhou 《World Journal of Clinical Cases》 SCIE 2024年第25期5814-5820,共7页
BACKGROUND An ependymoma is a glial tumor that usually occurs in or near the ventricle,close to the ependyma.It rarely occurs exclusively in the brain parenchyma without being associated with the ventricle.CASE SUMMAR... BACKGROUND An ependymoma is a glial tumor that usually occurs in or near the ventricle,close to the ependyma.It rarely occurs exclusively in the brain parenchyma without being associated with the ventricle.CASE SUMMARY Here,we report a rare case of a cerebellar ependymoma completely located in the brain parenchyma.A previously healthy 32-year-old female with a 1-month history of dizziness was admitted to our hospital.During hospitalization,magnetic resonance imaging of the brain revealed a space-occupying lesion measuring 57 mm×41 mm×51 mm in the right cerebellar hemisphere and inferior cerebellar vermis.The patient underwent surgical resection for the right cerebellar mass.Postoperative pathological examination revealed an ependymoma.At 1 year follow-up,the patient was doing well and showed no recurrence.CONCLUSION We conducted a literature review and summarized three theories regarding ependymomas located exclusively in the brain parenchyma,which are key to the diagnosis of intraparenchymal cerebellar ependymomas.Surgery and postoperative radiotherapy are the primary treatment options for ependymomas. 展开更多
关键词 Cerebellar ependymoma Brain parenchyma MECHANISMS SURGERY Case report
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光敏核不育水稻花药中Ca^(2+)分布及其与花粉育性的相关性研究 被引量:3
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作者 邓芳 史银连 姚家玲 《中国农业科学》 CAS CSCD 北大核心 2009年第3期809-815,共7页
【目的】研究光敏核不育水稻花药发育过程中Ca2+分布与花粉败育的关系。【方法】采用焦锑酸钾沉淀法,研究光敏核不育水稻农垦58S和可育品种农垦58N花药发育过程中药隔、药壁和花粉细胞中Ca2+的分布变化。【结果】不育花药与可育花药中C... 【目的】研究光敏核不育水稻花药发育过程中Ca2+分布与花粉败育的关系。【方法】采用焦锑酸钾沉淀法,研究光敏核不育水稻农垦58S和可育品种农垦58N花药发育过程中药隔、药壁和花粉细胞中Ca2+的分布变化。【结果】不育花药与可育花药中Ca2+分布有很多差异:(1)可育花粉细胞表面逐渐积累丰富的Ca2+沉淀,花粉壁发育完全,细胞质中Ca2+很少;而不育花粉细胞表面Ca2+较少,花粉壁形成异常,细胞质中积累丰富的Ca2+沉淀。(2)不育花药绒毡层提前启动解体,且解体过程十分缓慢;不育花药较可育花药提前形成乌氏体,但其表面无Ca2+沉淀直至单核晚期才有明显分布,且数量少于同期可育花药。总体上看,除乌氏体以外,不育花药各壁层细胞中的Ca2+沉淀多于可育花药。(3)花药发育过程中,药隔组织中的Ca2+沉淀逐渐增多,同期相比,不育花药多于可育花药。【结论】光敏核不育水稻绒毡层细胞提早解体及乌氏体功能异常,导致Ca2+向药室的运输发生障碍,致使花粉表面缺乏Ca2+而引起花粉外壁形成不正常;花粉发育后期细胞质内积累大量Ca2+是花粉败育的主要因素之一。 展开更多
关键词 光敏核不育水稻 CA2+ 花粉 药壁 药隔
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