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Expression of a New hemA Gene from Agrobacterium radiobacter in Escherichia coli for 5-Aminolevulinate Production 被引量:5
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作者 LIU Xiaoxia(刘晓侠) +5 位作者 lin Jianping(林建平) QIN Gang(秦钢) CEN Peilin(岑沛霖) 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期522-528,共7页
A new hemA gene encoding 5-aminolevulinate (ALA) synthase was cloned from Agrobacterium ra- diobacter zju-0121. The ALA synthase catalyzes the pyridoxal phosphate-dependent condensation of succinyl coen- zyme A (succi... A new hemA gene encoding 5-aminolevulinate (ALA) synthase was cloned from Agrobacterium ra- diobacter zju-0121. The ALA synthase catalyzes the pyridoxal phosphate-dependent condensation of succinyl coen- zyme A (succinyl-CoA) and glycine to produce ALA. Four plasmids carrying the A, radiobacter hemA gene were transformed into different E. coli strains. The effects of both genetic and physiological factors on the expression of ALA synthase and ALA production were studied. The results indicated that the final intracellular activity of ALA synthase and the production of ALA in different expression systems varied largely. Among them, the recombinant E. coli BL21 (DE3) harboring the expression plasmid pET28-A. R-hemA was the most suitable one. The effects of isopropyl-β-D-thiogalactopyranoside (IPTG) addition time, IPTG concentration, culture temperature and the initial concentration of precursors and glucose on the ALA production were also evaluated. The expressed ALA synthase accounted for about 23.7% of the intracellular soluble protein. The highest specific activity of ALA syn- thase was 13.8nmol·min-1·mg-1 of intracellular soluble protein. In the batch culture of the recombinant E. coli, the extracellular ALA concentration reached 0.9 g·L-1. 展开更多
关键词 5-aminolevulinate (ALA) ALA synthase metabolic engineering
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PARAMETER ITERATION METHOD FOR SOLVING NONLINEAR PROBLEM 被引量:1
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作者 lin Jiang-guo(林建国) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第7期836-841,共6页
The parameter iteration method was developed for solving the nonlinear problem in this paper. The results of several examples show that even the first iteration solution has very good accuracy.
关键词 NONLINEAR parameter iteration approach solution
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NUMERICAL SIMULATION OF ORIENTATION DISTRIBUTION FUNCTION OF CYLINDRICAL PARTICLE SUSPENSIONS
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作者 lin Jian-zhong(林建忠) +1 位作者 ZHANG ling-xin(张凌新) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期906-912,共7页
The orientation distribution function of cylindrical particle suspensions was deduced and numerically simulated, and an application was taken in a wedge-shaped flow field. The relationship between the orientation dist... The orientation distribution function of cylindrical particle suspensions was deduced and numerically simulated, and an application was taken in a wedge-shaped flow field. The relationship between the orientation distribution function and particle orientation angles was obtained. The results show that comparing with the most probable angle distribution which comes to being in short time, the distribution of the steady state doesn't vary much. in range; the main difference is the anti-clockwise rotation in the right and upper field, that is, particles rotate more at the points where the velocity gradients are larger. The most probable orientations are close to the direction of local streamlines. In the direction of streamlines, with poleradius decreasing, the most probable angles increase, but the angles between their orientations and the local streamlines decrease. 展开更多
关键词 cylindrical particle suspension wedge-shaped flow orientation distribution function most probable angle numerical simulation
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Two New Compounds from Hemsleya penxianensis var. gulinensis
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作者 Yu Ping +4 位作者 lin Ming Hua CHIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期169-172,共4页
Two new compounds, oleanolic acid 28-O--D-glucopyranosyl-3-O--L-arabinopyrano- syl-(13)-(6-butyl ester)--D-glucuropyranoside 1, oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranoside 2 have been isolated from ... Two new compounds, oleanolic acid 28-O--D-glucopyranosyl-3-O--L-arabinopyrano- syl-(13)-(6-butyl ester)--D-glucuropyranoside 1, oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranoside 2 have been isolated from the roots of Hemsleya penxianensis var. gulinensis. Their structures were determined on the bases of the spectral and chemical evidences. 展开更多
关键词 Hemsleya penxianensis var. gulinensis CUCURBITACEAE oleanolic acid 28-O--D-glucop -yranosyl-3-O--L-arabinopyranosyl-(13)-(6-butyl ester)--D-glucuropyranoside oleanolic acid 28-O--D-glucopyranosyl-(16)--D-glucopyranoside.
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The Offline Program Profile Lining and Cutting Robot System
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作者 王于 Ding +6 位作者 Guoqing lin Liangming Wang Hongjie Wang Zhiwu 《High Technology Letters》 EI CAS 2001年第2期71-75,共5页
The paper introduces a new type of cutting system: the Offline Program Profile Lining and Cutting Robot System (OPPLCRS). The system adopts the offline program technology without teaching. The system can measure and c... The paper introduces a new type of cutting system: the Offline Program Profile Lining and Cutting Robot System (OPPLCRS). The system adopts the offline program technology without teaching. The system can measure and compensate every profile’s deformation automatically, so it is suit to process any batch of profiles, and the order of processing different profiles can be arranged at will. The OPPLCRS, firstly appearing in China, will have wide application in profile cutting fields. 展开更多
关键词 Cutting robot Offline program COMPENSATION User-describing-language Interface
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Off-line Programming Technology Based on RPC Communication Method and its Application
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作者 王宏杰 Ding +6 位作者 Guoqing Yan Guozheng Zhu Honghai lin Liangming 《High Technology Letters》 EI CAS 2001年第4期63-68,共6页
This paper puts forward a communication programming method between robot and external computer based on RPC (Remote Produce Call) communication method, which realizes robot distributed controlling network system model... This paper puts forward a communication programming method between robot and external computer based on RPC (Remote Produce Call) communication method, which realizes robot distributed controlling network system model. And a new Robot off line programming method is built based on this communication method and network model. Further more, as an example, robot auto marking and auto cutting of shipbuilding profile system is developed, which proves the ideas of author’s off line programming and development methods of robot flexible automation system. As a result, this paper presents a new method for developing robot flexible automation system. 展开更多
关键词 Off line programming RPC communication Robot flexible automation Profile processing
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Clinical and Biological Significance of Clonal Macrophage Detection in Hemophagocytic Syndrome 被引量:1
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作者 lin Wen(林雯) +3 位作者 XIAO Yan(肖燕) FEI Hongbao(费洪宝) 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期126-128,共3页
Summary: By using the method of clonal analysis the evidence to prove that Hemophagocytic syndrome (HPS) is reactive or malignant was investigated to probe into the pathogenesis of HPS and its relations with clinical ... Summary: By using the method of clonal analysis the evidence to prove that Hemophagocytic syndrome (HPS) is reactive or malignant was investigated to probe into the pathogenesis of HPS and its relations with clinical prognosis. The macrophages abnormally proliferated in bone marrow were isolated. Electrophoresis analysis was made after DNA extraction, enzyme restriction of human ardrogen receptor (HUMARA) genetic locus, and PCR amplification. In the 9 specimens, clonal proliferation was found in 2 cases and nonclonal proliferation in 7. Among the 7 cases of nonclonal proliferation, 3 were voluntarily discharged without clinical outcome, 2 cases fully recovered after 2-3 week treatment of large dose gamma globulin intravenous drip and hormone therapy, 1 case died at the 43th day after the hormone and anti-infection therapy, and one case was found to have granular leukoblast in peripheral blood after 3 weeks and diagnosed as having M2a after bone puncture. For the two patients with clonal proliferation, one obtained remission after chemotherapy and the other was died after 32 days without chemotherapy. It was concluded that there do exist clonal or malignant proliferation in HPS, so not every case is reactive. 展开更多
关键词 hemophagocytic syndrome CLONE CHEMOTHERAPY
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Preparation of an imaging agent for cerebral muscarinic acetylcholine receptor, (R,S)(131)~I-QNB
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作者 NING Shi-Yu +2 位作者 lin Yan-Song 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第1期64-65,共2页
The method to synthesize a high affinity muscarinic receptor antagonist (R,S)I-QNB[(R)-(-)-1-azabicyclo [2,2,2]oct-3-yl-(S)-(+)-α-hydroxy-α-(4-[127I]iodophenyl)-α-phenyl acetate] from 4-nitrobenzophenone with impro... The method to synthesize a high affinity muscarinic receptor antagonist (R,S)I-QNB[(R)-(-)-1-azabicyclo [2,2,2]oct-3-yl-(S)-(+)-α-hydroxy-α-(4-[127I]iodophenyl)-α-phenyl acetate] from 4-nitrobenzophenone with improvement compared to literatures was reported in this article. IR, MS and 1HNMR characterized the final product. (R,S)131I-QNB was prepared using Cu(I) assisted iodine exchange labeling, and showed by TLC that the radiolabeling yield(RLY) was over 80%, and radiochemical purity(RCP) was over 95%. Stability of the labeled compound was also determined. It was found that (R,S)131I-QNB dried by nitrogen blowing can stay at 4-10℃ for a week without change of RCP. 展开更多
关键词 (R S)I-QNB 合成 碘131 放射性同位素 标记 表征 IR MS NMR
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A Novel Processor Scheduling Schema in Programmable Router Based on Queue Length Thresholds
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作者 徐恪 lin +2 位作者 Chuang Wu Jianping 《High Technology Letters》 EI CAS 2004年第1期1-7,共7页
Programmable router may execute computing tasks except for forwarding IP packets. How to schedule the CPU in the programmable router is an important issue that needs to be solved. In this paper, the authors establish ... Programmable router may execute computing tasks except for forwarding IP packets. How to schedule the CPU in the programmable router is an important issue that needs to be solved. In this paper, the authors establish general software architecture of programmable router firstly. Based on this architecture, authors present a novel CPU scheduling algorithm based on queue length thresholds. We model this algorithm using stochastic Petri nets. The analytic results show that this scheduling algorithm can guarantee the requirements of computing of best-effort flows and QoS flows in programmable router at the same time. 展开更多
关键词 处理器 时序安排算法 可编程路由器 队列长度门限 CPU PETRI网 QoS流
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漓江谣曲:阳朔的山水慢板
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作者 lin 四食不惑(图) +3 位作者 云上闻庐(图) 兰江平(图) 歪歪牛(图) 何李欣(图) 《城市地理》 2025年第7期94-99,共6页
广西腹地,漓江水在喀斯特峰林间流淌千年,雕琢出阳朔这片独绝的山水画卷。碧水映照下的峰林,犹如新笋拔节般簇立于江畔;深坳村落中,依然回响着古朴的傩戏鼓点;而辣椒炝出的酸笋咸香,在空气中弥漫……一切都在这里交融、延展,最终织就了... 广西腹地,漓江水在喀斯特峰林间流淌千年,雕琢出阳朔这片独绝的山水画卷。碧水映照下的峰林,犹如新笋拔节般簇立于江畔;深坳村落中,依然回响着古朴的傩戏鼓点;而辣椒炝出的酸笋咸香,在空气中弥漫……一切都在这里交融、延展,最终织就了阳朔独一无二的气韵。 展开更多
关键词 碧水 阳朔 漓江 喀斯特峰林 山水画卷
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碳酸亚乙烯酯:有机合成化学中的多功能合成子 被引量:2
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作者 林雨 付海峰 +1 位作者 曹华 刘想 《有机化学》 SCIE CAS CSCD 北大核心 2024年第7期2147-2173,共27页
近年来,碳酸亚乙烯酯已成为一种新型、理想的多功能合成子,广泛应用于丰富多样的有机合成转化中,特别是在过渡金属催化的C—H官能化领域,可用于构建含碳、杂环骨架的目标分子.自2009年Nishii和Miura首次报道了碳酸亚乙烯酯作为“乙炔醇... 近年来,碳酸亚乙烯酯已成为一种新型、理想的多功能合成子,广泛应用于丰富多样的有机合成转化中,特别是在过渡金属催化的C—H官能化领域,可用于构建含碳、杂环骨架的目标分子.自2009年Nishii和Miura首次报道了碳酸亚乙烯酯作为“乙炔醇替代物”参与偶联反应以来,其作为“乙炔替代物”、“C1合成子”、“酰甲基化试剂”及其它功能试剂的应用被陆续报道.这些进展不仅凸现了碳酸亚乙烯酯的多功能转化性,也为复杂化合物的合成提供新思路.根据碳酸亚乙烯酯在合成化学中的不同反应角色,概述了近年来碳酸亚乙烯酯的最新研究进展,并对其未来发展提出展望. 展开更多
关键词 碳酸亚乙烯酯 C—H官能化 环化反应 氮杂环
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The role of endotoxin,TNF-α,and IL-6 in inducing the state of growth hormone insensitivity 被引量:31
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作者 WangP lin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期531-536,共6页
AIM: Critical illnesses such as sepsis, trauma, and burns cause a growth hormone insensitivity, which leads to an increased negative nitrogen balance. Endotoxin is generously released into blood under these conditions... AIM: Critical illnesses such as sepsis, trauma, and burns cause a growth hormone insensitivity, which leads to an increased negative nitrogen balance. Endotoxin is generously released into blood under these conditions and stimulates the production of proinflammatory cytokines such as TNF-alpha, IL-6, and IL-1, which may play a very important role in inducing the growth hormone insensitivity. The objective of this current study was to investigate the role of endotoxin, TNF-alpha and IL-6 in inducing the growth hormone insensitivity at the receptor and post-receptor levels. METHODS: Spague-Dawley rats were injected with endotoxin, TNF-alpha, and IL-6, respectively and part of rats injected with endotoxin was treated with exogenous somatotropin simultaneously. All rats were killed at different time points. The expression of IGF-I, GHR, SOCS-3 and beta-actin mRNA in the liver was detected by RT-PCR and the GH levels were measured by radioimmunoassay, the levels of TNF-alpha and IL-6 were detected by ELISA. RESULTS: There was no significant difference in serous GH levels between experimental group and control rats after endotoxin injection, however, liver IGF-I mRNA expression had been obviously down-regulated in endotoxemic rats. Liver GHR mRNA expression also had a predominant down-regulation after endotoxin injection. The lowest regulation of liver IGF-I mRNA expression occurred at 12h after LPS injection, being decreased by 53% compared with control rats. For GHR mRNA expression, the lowest expression occurred at 8h and had a 81% decrease. Although SOCS-3 mRNA was weakly expressed in control rats, it was strongly up-regulated after LPS injection and had a 7.84 times increase compared with control rats. Exogenous GH could enhance IGF-I mRNA expression in control rats, but it did fail to prevent the decline in IGF-I mRNA expression in endotoxemic rats. Endotoxin stimulated the production of TNF-alpha and IL-6, and the elevated IL-6 levels was shown a positive correlation with increased SOCS-3 mRNA expression. The liver GHR mRNA expression was obviously down-regulated after TNF-alpha iv injection and had a 40% decrease at 8h, but the liver SOCS-3 mRNA expression was the 4.94 times up-regulation occurred at 40 min after IL-6 injection. CONCLUSION: The growth hormone insensitivity could be induced by LPS injection, which was associated with down-regulated GHR mRNA expression at receptor level and with up-regulated SOCS-3 mRNA expression at post-receptor level. The in vivo biological activities of LPS were mediated by TNF-alpha and IL-6 indirectly, and TNF-alpha and IL-6 may exert their effects on the receptor and post-receptor levels respectively. 展开更多
关键词 Repressor Proteins Transcription Factors Animals Drug Resistance Growth Hormone Insulin-Like Growth Factor I INTERLEUKIN-6 LIPOPOLYSACCHARIDES Male Proteins RNA Messenger RATS Rats Sprague-Dawley Receptors Somatotropin Research Support Non-U.S. Gov't Suppressor of Cytokine Signaling Proteins Tumor Necrosis Factor-alpha
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基于工程教育专业认证的高分子化学课程教学改革
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作者 陈亚举 马浩 乔艳辉 《科教导刊》 2024年第24期96-98,共3页
高分子化学作为应用化学专业的一门核心课程,其教学质量对学生能力培养和工程教育专业认证具有重要意义。文章基于“以学生中心、产出导向、持续改进”的理念,分析了高分子化学课程的教学现状与面临的挑战,从改进课程目标、优化课程内... 高分子化学作为应用化学专业的一门核心课程,其教学质量对学生能力培养和工程教育专业认证具有重要意义。文章基于“以学生中心、产出导向、持续改进”的理念,分析了高分子化学课程的教学现状与面临的挑战,从改进课程目标、优化课程内容、完善教学方法和建立合理的课程质量评价与持续改进体系等方面,探讨了高分子化学课程的教学改革途径。 展开更多
关键词 工程教育专业认证 教学改革 高分子化学 持续改进
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新型IGCC系统的开拓与集成技术 被引量:18
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作者 林汝谋 徐玉杰 +12 位作者 徐钢 金红光 邓润亚 DENG Run-ya JIN Hong-guang XU Gang XU Yu-jie lin Ru-mou 《燃气轮机技术》 2005年第1期7-15,6,共10页
本文基于大量相关研究,全面总结分析了新型IGCC系统的开拓及其集成技术开发与进展。首先分析了IGCC固有的效率高、环保性能优以及最具发展潜力等特点,以揭示其具有的发展前景和受到重视的原因;然后总结介绍了正在发展的燃料电池-IGCC联... 本文基于大量相关研究,全面总结分析了新型IGCC系统的开拓及其集成技术开发与进展。首先分析了IGCC固有的效率高、环保性能优以及最具发展潜力等特点,以揭示其具有的发展前景和受到重视的原因;然后总结介绍了正在发展的燃料电池-IGCC联合循环、IGCC多联产、CO2零排放的IGCC以及燃料多样化的IGCC等新型系统,并扼要论述这些新系统整合机理和特性。还归纳介绍了先进的燃气轮机技术、离子膜制氧技术等集成技术开发与进展。 展开更多
关键词 新型 IGCC 系统开拓 集成技术
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动力学环境下含裂纹板力学性能分析与试验 被引量:1
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作者 林凯 吕国志 +3 位作者 lin Kai L Guo-zhi 《机械科学与技术》 CSCD 北大核心 2000年第z1期99-100,177,共3页
通过试验探讨了平板弯曲问题中裂纹长度和位置对结构固有频率的影响;加载频 率对裂纹扩展速率的影响;在振动环境中裂纹扩展速率da/dN与应力强度因子幅 △K的关系。利用细长菱形裂缝处理裂纹,求解裂纹对结构固有频率影响。实现... 通过试验探讨了平板弯曲问题中裂纹长度和位置对结构固有频率的影响;加载频 率对裂纹扩展速率的影响;在振动环境中裂纹扩展速率da/dN与应力强度因子幅 △K的关系。利用细长菱形裂缝处理裂纹,求解裂纹对结构固有频率影响。实现了板弯 裂纹扩展和频率测试试验,得到了有意义的数据。分析结果与试验结构吻合较好。 展开更多
关键词 弹性薄板 旋转弯曲疲劳试验机 七点增量法
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关于黄石加快融入光谷科创大走廊的对策研究 被引量:1
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作者 李琳 郭小燕 《湖北理工学院学报(人文社会科学版)》 2021年第4期42-46,共5页
为顺应全球科技发展趋势、国家创新驱动发展战略和湖北创新强省建设的需要,中共湖北省委、省政府作出规划建设光谷科技创新大走廊的重大战略部署,着力打造我国重要的科技创新策源地和高质量发展示范区。当前,黄石市正处在深度转型的关... 为顺应全球科技发展趋势、国家创新驱动发展战略和湖北创新强省建设的需要,中共湖北省委、省政府作出规划建设光谷科技创新大走廊的重大战略部署,着力打造我国重要的科技创新策源地和高质量发展示范区。当前,黄石市正处在深度转型的关键时期和大有可为的重要战略机遇期。主动融入光谷科创大走廊,大力推动黄石与武汉、鄂州、黄冈协同创新发展,是黄石实现引领鄂东转型发展示范区高质量发展的必然选择。如何加快融入光谷科创大走廊建设、用好优势资源、做好“融入”文章、在区域协同创新中争当“主角”,这是目前黄石亟需研究解决的问题。 展开更多
关键词 黄石 光谷科创大走廊 协同创新 融入
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甲状腺微小癌经胸乳入路与经颈部入路微创腔镜手术治疗效果、并发症及美观满意度分析 被引量:5
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作者 林旭辉 《系统医学》 2019年第12期101-103,共3页
目的探索甲状腺微小癌经胸乳入路与经颈部入路微创腔镜手术治疗效果、并发症及美观满意度。方法选取2017年7月—2018年7月期间该院甲状腺微小癌100例患者(实施奇偶数分组模式),对照组的50例患者进行经颈部入路治疗,观察组的50例患者进... 目的探索甲状腺微小癌经胸乳入路与经颈部入路微创腔镜手术治疗效果、并发症及美观满意度。方法选取2017年7月—2018年7月期间该院甲状腺微小癌100例患者(实施奇偶数分组模式),对照组的50例患者进行经颈部入路治疗,观察组的50例患者进行经胸乳入路治疗,随后对比两组患者TSH、T4、FT4、FT3、并发症发生率、术后引流量、术中出血量、手术时间、住院时间、术后3 d VAS评分、美容效果满意度。结果观察组TSH(1.11±0.05)mU/L、T4(7.20±0.19)μg/dL、FT4(1.76±0.68)ng/dL、FT3(2.15±0.21)ng/dL、并发症发生率(4.00%)、术后引流量(81.43±8.95)mL、术中出血量(24.18±4.33)mL、手术时间(48.95±5.33)min、住院时间(5.46±1.33)d、术后3 d VAS评分(1.49±0.24)分、美容效果满意度(100.00%)均优于对照组(t/χ^2=1.236 5、1.542 5、1.133 5、1.062 3、11.086 5、15.395 6、10.132 8、24.865 8、17.865 2、6.842 5、14.185 6;P<0.05)。结论胸乳入路微创腔镜手术在甲状腺微小癌患者中效果更为明显。 展开更多
关键词 甲状腺微小癌 经胸乳入路 经颈部入路 腔镜手术 并发症 美观满意度
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陈嘉庚的忧患意识及其启示 被引量:1
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作者 林德时 lin De-shi 《集美大学学报(哲学社会科学版)》 2001年第2期116-118,共3页
通过对陈嘉庚爱国主义精神中忧患意识的主要成因与内容的归纳 ,揭示了厦门人民增强忧患意识 。
关键词 陈嘉庚 爱国主义 忧患意识 成因 国家主权 国家统一
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学校体育教学中的素质教育
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作者 雷玲 LEI lin 《西南民族学院学报(哲学社会科学版)》 北大核心 2002年第9期247-249,277,共3页
应试教育关注显性学力 ,素质教育则关注显性学力与隐性学力的统一 ;学校体育要从个性化教育、学力成长、课程文化的再创造视角出发探寻 。
关键词 学校体育教学 素质教育 个性化教育 课程文化 显性学力 隐性学力 人格
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中国北天山晚石炭世白杨沟火山岩的成因及地质意义 被引量:3
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作者 颉炜 祝近近 +1 位作者 罗震宇 徐义刚 《岩石学报》 SCIE EI CAS CSCD 北大核心 2018年第1期126-142,共17页
中国北天山作为中亚造山带西部重要的组成部分,其晚古生代的构造背景长期存在板内裂谷环境和岛弧环境两个截然不同的认识,有些学者还提出该地区有塔里木地幔柱的影响,从石炭纪到二叠纪均发育大量的双峰式火山岩。为了厘定其石炭-二叠纪... 中国北天山作为中亚造山带西部重要的组成部分,其晚古生代的构造背景长期存在板内裂谷环境和岛弧环境两个截然不同的认识,有些学者还提出该地区有塔里木地幔柱的影响,从石炭纪到二叠纪均发育大量的双峰式火山岩。为了厘定其石炭-二叠纪模糊不清的构造属性以及火山岩的地质特征,本文对北天山博格达隆起带白杨沟地区火山岩进行了系统的研究。这套火山岩由枕状玄武岩、块状玄武岩、安山-英安质熔结凝灰岩、流纹岩和火山角砾岩组成。安山-英安质熔结凝灰岩和流纹岩属于Ⅰ型酸性岩,与枕状玄武岩及块状玄武岩整合接触。海相棘皮类化石的发现以及锆石SHRIMP U-Pb年龄(~311Ma)的测定指示这套白杨沟火山岩应属于晚石炭世祁家沟组。同时,安山-英安质熔结凝灰岩的发现表明白杨沟火山岩剖面并非双峰式火山岩,但与双峰式岩浆(玄武质和流纹质岩浆)有密切的成因关系。MELTS模拟计算指示白杨沟流纹岩和熔结凝灰岩不是与其共生的玄武岩高度结晶分异的产物。与含水玄武质岩石的部分熔融实验对比,正的ε_(Nd)(t)值(+5.9^+7.5)以及岛弧特征的微量元素性质则表明白杨沟流纹岩和熔结凝灰岩主要由含水的新生岛弧玄武质地壳(岩石)发生部分熔融形成。流纹岩很可能代表新生地壳部分熔融的直接产物。然而熔结凝灰岩中发育玄武质和长英质两类浆屑,大量斜长石晶屑的发育以及负Eu至正Eu异常(δEu=0.8~1.1)暗示安山-英安质熔结凝灰岩还受岩浆混合作用和长石堆晶作用的影响。结合博格达晚石炭世玄武岩的研究,本文认为博格达晚石炭世应为洋内岛弧后弧或弧后环境,与北天山洋(或称为准噶尔洋)向南俯冲有关。博格达隆起带石炭-二叠纪构造属性的转变很可能与东准噶尔弧和博格达弧在石炭-二叠纪界限时期发生的弧-弧碰撞作用有关。 展开更多
关键词 中国北天山 博格达隆起带 晚石炭世 熔结凝灰岩 岛弧后弧或弧后环境
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