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Histological study of vas deferens following intravasallaser irradiation

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Asian Journal of Andrology 2003年第4期5卷 287-294页

作者： Xiao-HongWen Xin-MinXiao PengHuang Xian-YongXie zheng-weiyang MorphometricResearchLaboratory DepartmentofUrology ChinesePLA452ndHospitalChengdu610021China DepartmentofPathology NorthSichuanMedicalCollegeNanchong637007China

Aim: To study the histologic changes of the vas deferens following Nd: YAG laser irradiation. Methods: Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W-50 W) and 16 segments of human (3 seconds at 45 W-55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds-2.5 seconds at 40 W-45 W) in vivo and (iii) 2 human vasa (3 seconds at 55W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days-180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25μm-30μm) were obtained and observed under a light microscope. Results: (i) Laser-induced damage reached the muscularis layer in 27 % and 94 % of the rabbit and human vas segments in vitro, respectively, (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage, (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer. Conclusion: Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.

关键词： histology laser male contraception photocoagulation vas deferens vas occlusion

Quantitative (stereological) study of incomplete spermatogenic suppression induced by testosterone undecanoate injection in rats

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Asian Journal of Andrology 2004年第4期6卷 291-297页

作者： zheng-weiyang YangGuo LiLin Xing-HaiWang Jian-SunTong Gui-YuanZhang MorphometricResearchLaboratory NorthSichuanMedicalCollegeNanchong637007China PhotographyStudio NanchongMedicalSchoolNanchong637000China JiangsuFamilyPlanningInstitute Nanjing210029China NationalResearchInstituteforFamilyPlanning Beijing100081China

Aim: To evaluate the key lesions in spermatogenesis suppressed partially by testosterone undecanoate (TU) treatment. Methods: Adult male SD rats were treated with vehicle or TU (19 mg/kg) injection (i.m.) every 15 days for 130 days. The numbers of all types of cells (nuclei) in the seminiferous tubules and the interstitial tissue were estimated using a contemporary stereological tool, the optical disector. Results: In response to TU treatment, the numbers of non-type B spermatogonia, type B spermatogonia and late elongated spermatids per testis were reduced to 51 %, 66 % and 14 % of the controls, respectively. The conversion ratios from type B spermatogonia to early spermatocytes and pachytene spermatocytes were not significantly affected and the ratios to the later germ cell types fell to 51 % - 65 % of the controls. Less than 1.0 % of immature round spermatids were seen sloughing into the tubule lumen, 4.0 % of elongated spermatids retained in the seminiferous epithelium, and about half of the elongated spermatid nuclei appreciably malformed. Leydig cells were atrophied but their number and the peritubular myoid cell number per testis were unchanged. Conclusion: Double inhibition of spermatogenesis (i.e. inhibition at spermiation and spermatogonial conversion to type B spermatogonia), a scenario seen in the monkey and human following gona-dotrophin withdrawal, was not sufficiently effective for a complete spermatogenic suppression in the rat after TU treatment, probably due to ineffective inhibition of the Leydig cell population and therefore the intra-testicular testosterone levels.

关键词： Leydig cells rat spermatogenesis spermatogenic cells stereology testis testosterone

Reversible effect of testosterone undecanoate injection on spermatogenesis in rats

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Asian Journal of Andrology 2000年第3期2卷 207-211页

作者： Xiao-HongWEN Wing-HaiWANG Jian-SunTONG zheng-weiyang Gui-YuanZHANG MorphometricResearchLaboratory NortltSichuanMedicalCollegeNanchong637007 JiangsuScientificandTechnologicalInstituteforFamilyPlonning Nanjing210029 DepartmentofEndocrinology NationalResearchInstituteforFamilyPlanningBeijing100081China

Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminif-erous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereologicalmethods as a measure of the spermatogenic efficiency. Results: Low dose (8 mg/kg) TU treatment virtually hadno effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and se-vere suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of therecovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well toler-ated by animals. Conclusion: TU injection reversibly suppresses spermatogenesis in rats.

关键词： spermatogenesis stereology testis testosterone undecanoate

基于鸡粪养殖的黑水虻幼虫复合滚筒筛参数研究

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河南农业大学学报 2024年第1期58卷 115-122页

作者：郑维扬于永民蒋本豫杨梦玮齐露露杨森中原工学院机电学院河南郑州451191 郑州乾正自动化科技有限公司河南郑州451191 河南农业大学生命科学学院河南郑州450046

【目的】解决鸡粪养殖黑水虻虫沙结块分离难、黑水虻幼虫损失率高及分离设备筛分效率低的问题,探究筛分参数对黑水虻幼虫复合滚筒筛筛分效果的影响。【方法】在借助离散元软件构建滚筒筛物料颗粒筛分过程仿真模型的基础上,以外层滚筒转... 详细信息

【目的】解决鸡粪养殖黑水虻虫沙结块分离难、黑水虻幼虫损失率高及分离设备筛分效率低的问题,探究筛分参数对黑水虻幼虫复合滚筒筛筛分效果的影响。【方法】在借助离散元软件构建滚筒筛物料颗粒筛分过程仿真模型的基础上,以外层滚筒转速、抄板高度、内层滚筒转速和滚筒倾角为试验因素,进行了4因素3水平正交试验,分析得到筛分效率和黑水虻幼虫损失率的最优筛分参数组合。【结果】当外层滚筒转速36 r·min^(-1),抄板高度20 mm,内层滚筒转速-45 r·min^(-1),滚筒倾角8°时,滚筒筛性能最优,筛分效率为95.32%,损失率为4.85%;在最优筛分参数组合条件下,样机试验结果与仿真试验结果相对误差分别为4.19%和0.55%,仿真试验与样机试验结果吻合度较好。【结论】解决了黑水虻幼虫分离设备现存问题,获得了滚筒筛分的最佳筛分参数,为黑水虻幼虫筛分设备相关研究提供参考。

关键词：滚筒筛黑水虻幼虫虫料分离鸡粪 EDEM仿真筛分参数

Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu zheng weiyang QIN Ruilan TIAN Hu DING J.C.JI Liqun CHEN Department of Engineering Mechanics North University of ChinaTaiyuan 030051China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-Carlo method(MCM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

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模拟教学中单纯间断缝合的学习曲线的研究

中国高等医学教育 2024年第1期 77-78页

作者：陈庭利江汕赵明利蒋冰阳郑维扬秦再生南方医科大学南方医院广东广州510515

目的:探索医学生单纯间断缝合的学习曲线,帮助指导临床教学。方法:6名学生每天进行6组单纯间断缝合训练(每组10针),共持续20天。从缝合速度和缝合质量两方面评价学习效果。结论:进行30组训练后学生的缝合速度和缝合质量即可达到较为满... 详细信息

目的:探索医学生单纯间断缝合的学习曲线,帮助指导临床教学。方法:6名学生每天进行6组单纯间断缝合训练(每组10针),共持续20天。从缝合速度和缝合质量两方面评价学习效果。结论:进行30组训练后学生的缝合速度和缝合质量即可达到较为满意的水平。如需进一步提速,至少需要75组训练。

关键词：单纯间断缝合模拟教学学习曲线医学生

同方期刊数据库博看期刊评论

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小肠间质瘤并发消化道出血的临床特征分析

临床内科杂志 2024年第7期41卷 456-459页

作者：王琦璞柏小寅徐天铭唐颢郑威扬李骥李景南中国医学科学院、北京协和医学院、北京协和医院消化内科北京100730

目的探讨小肠间质瘤的临床特征及其并发消化道出血的危险因素。方法对我院2012年5月~2021年12月手术治疗的317例原发小肠间质瘤患者进行回顾性分析,其中男167例(52.7%)、女150例(7.3%),中位起病年龄55(46,63)岁,中位病程90(30,365)天... 详细信息

目的探讨小肠间质瘤的临床特征及其并发消化道出血的危险因素。方法对我院2012年5月~2021年12月手术治疗的317例原发小肠间质瘤患者进行回顾性分析,其中男167例(52.7%)、女150例(7.3%),中位起病年龄55(46,63)岁,中位病程90(30,365)天。采用多因素logistic回归分析评估小肠间质瘤患者消化道出血的影响因素。结果所有患者中,小肠间质瘤位于十二指肠112例(35.3%)、空肠113例(35.6%)和回肠92例(29.0%);肿瘤中位直径5.2(3.0,8.0)cm;10.1%合并其他恶性肿瘤。消化道出血(46.4%)是最常见的临床表现,其次是腹痛(21.1%)、体重下降(15.1%)、腹胀(7.3%)、腹部包块(6.6%);并发症包括肠梗阻(5.4%)、间质瘤内出血(4.4%)、肠穿孔(1.3%),23.7%患者无症状。病程长、TNM分期为T2和T3期是小肠间质瘤患者消化道出血的危险因素;诊断间质瘤同期诊断恶性肿瘤、恶性肿瘤家族史、腹痛是其保护因素(P<0.05)。结论消化道出血是小肠间质瘤患者最常见的临床表现,对于病程长、TNM分期为T2和T3期小肠间质瘤患者需警惕消化道出血的风险。

关键词：小肠间质瘤消化道出血临床特征危险因素

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模拟教学中腹腔镜训练的学习曲线的研究

中国高等医学教育 2024年第5期 72-73,76页

作者：陈庭利赵明利谭万龙李飞蒋冰阳江汕郑维扬秦再生南方医科大学南方医院广东广州510515

目的:探索模拟教学中腹腔镜训练的学习曲线。方法:利用腹腔镜手术训练箱模拟人体腹腔进行移物和剪切训练。记录5分钟内移动的黄豆数目,记录剪切一个标准圆所需的时间。结论:完成25组移物训练后,5分钟内可移动85颗黄豆;完成40组剪切训练... 详细信息

目的:探索模拟教学中腹腔镜训练的学习曲线。方法:利用腹腔镜手术训练箱模拟人体腹腔进行移物和剪切训练。记录5分钟内移动的黄豆数目,记录剪切一个标准圆所需的时间。结论:完成25组移物训练后,5分钟内可移动85颗黄豆;完成40组剪切训练后,3分钟可剪切一个标准圆。

关键词：腹腔镜模拟教学学习曲线移物剪切

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin