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机械传动 2018年第5期42卷 148-150,155页

作者：刘毅张孟九逄宁宁青岛征和工业股份有限公司山东青岛266708

采用Q235B热轧态原材料,在经渗碳淬火后的金相检验过程中,链轮次表层出现托氏体层,此层严重降低了表层与基体的结合力,并在交界处产生显微裂纹,影响了链轮的抗冲击性能和疲劳强度。通过实验找出了产生托氏体层的原因,并进行了改善,消除... 详细信息

采用Q235B热轧态原材料,在经渗碳淬火后的金相检验过程中,链轮次表层出现托氏体层,此层严重降低了表层与基体的结合力,并在交界处产生显微裂纹,影响了链轮的抗冲击性能和疲劳强度。通过实验找出了产生托氏体层的原因,并进行了改善,消除了淬火时产生的托氏体层,提升链轮的整体性能。

关键词：链轮渗碳淬火托氏体结合力疲劳强度

应用骨量及骨强度变化评估壁虎提取物改善骨质疏松大鼠的生物效应

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中国组织工程研究与临床康复 2007年第23期11卷 4516-4519页

作者：刘益善任东青郭伟慈延峰解放军空军总医院全军中西医结合正骨治疗中心北京市100036 解放军第四军医大学军事预防医学系放射医学教研室陕西省西安市710032 丹东市中心医院软伤科辽宁省丹东市118000

目的:通过观察骨量及生物力学指标,探讨中药壁虎提取物对影响骨组织构建正常结构骨质疏松的效应。方法:实验于2005-08/2006-07在解放军第四军医大学放射医学教研室完成。实验材料:健康8周龄雌性SD大鼠24只,体质量(220±15)g。壁虎提取... 详细信息

目的:通过观察骨量及生物力学指标,探讨中药壁虎提取物对影响骨组织构建正常结构骨质疏松的效应。方法:实验于2005-08/2006-07在解放军第四军医大学放射医学教研室完成。实验材料:健康8周龄雌性SD大鼠24只,体质量(220±15)g。壁虎提取物由解放军第四军医大学制备。实验分组:大鼠按体质量大小随机分为4组,即假手术组、模型组、预防组和治疗组,每组6只。实验干预:假手术组大鼠仅游离卵巢后关腹,其余各组大鼠均切除双侧卵巢。预防组大鼠术后6d开始灌胃用药,治疗组大鼠术后3个月开始灌胃用药,两组均按每日0.2g/kg体质量给予壁虎提取物1mL;假手术组和模型组大鼠术后6d给予等量注射用水灌胃。实验评估:术后6个月取各组大鼠骨组织,进行骨组织骨密度值、骨钙含量、最大应力、最大应变、弹性模量、骨皮质厚度等指标检测。结果:24只大鼠均进入结果分析。①骨密度和骨钙含量变化:假手术组与模型组相比各指标均有明显差异,表明骨质疏松动物模型制备是成功的。预防组和治疗组的全身骨密度值、腰椎骨密度值和骨钙含量均高于模型组大鼠(P<0.01)。②生物力学变化:预防组和治疗组的骨组织最大应力、最大应变及弹性模量高于模型组(P<0.01),但未能恢复到假手术组水平。③几何结构参数:预防组和治疗组的骨皮质厚度均较模型组增厚[(0.784±0.081),(0.686±0.077),(0.506±0.091)mm,P<0.01],两组的骨髓腔直径均较模型组降低[(1.993±0.149),(1.975±0.087),(2.120±0.098)mm,P<0.01和P<0.05]。结论:壁虎提取物可改善实验动物骨皮质厚度和髓腔径,增加骨量和骨强度,对骨组织构建影响因素骨质疏松有一定的防治作用。

关键词：骨质疏松壁虎科大鼠组织构建

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许旺细胞移植治疗晚期脊髓损伤的手术方法

中国组织工程研究与临床康复 2007年第3期11卷 509-511页

作者：封亚平刘艳生朱辉封雨沈彩虹解放军昆明总医院全军脊髓损伤治疗中心云南省昆明市650032

目的:观察采用许旺细胞脊髓腔内移植手术治疗晚期脊髓损伤患者,其神经恢复的疗效。方法:选择2001-03/2006-03在解放军昆明总医院脊髓损伤治疗科的完全截瘫患者47例。根据患者症状、体征、CT、核磁共振、美国脊髓损伤学会评分明确诊断。... 详细信息

目的:观察采用许旺细胞脊髓腔内移植手术治疗晚期脊髓损伤患者,其神经恢复的疗效。方法:选择2001-03/2006-03在解放军昆明总医院脊髓损伤治疗科的完全截瘫患者47例。根据患者症状、体征、CT、核磁共振、美国脊髓损伤学会评分明确诊断。男38例,女9例,平均31.4岁,均签知情同意书。致伤原因中车祸26例,高处坠落13例,刀伤1例,重物砸伤7例。脊髓损伤部位为颈段15例,T1～-6段12例,T7～12段20例。伤后至许旺细胞伤后平均移植时间26.8月。47例患者伤后在院外均接受过不同种类的神经营养或生长因子治疗及正规的康复治疗,其中37例在院外已行脊柱内固定及脊髓减压手术,疗效均不明显。47例除8例因内固定材料不宜行核磁共振检查外,其余均行核磁共振检查。取6个月左右流产胎儿脊神经背根用于许旺细胞培养,不影响许旺细胞移植。手术于全麻下行脊髓损伤节段后方入路,切开硬膜显露脊髓,显微镜下松解粘连,切除增厚的蛛网膜及疤痕组织,合并脊髓囊肿或空洞,于脊髓受损处,选择最薄、呈透明的部位纵形切开空洞,彻底清除囊腔内液化、坏死组织,用神经剥离子轻柔搔刮囊壁,生理盐水反复冲洗囊腔,直至冲洗液清亮。将附有许旺细胞的薇乔3-0紫色可吸收线按囊腔的长度剪好,置于囊腔内,滴入许旺细胞溶液1mL,再用附有许旺细胞的薇乔网覆盖,几丁糖封闭创面,敞开硬膜,放置明胶海绵放于硬脊膜外。置多侧孔引流管,逐层缝合切口。术后2周进行康复训练。许旺细胞移植后随访2～8周。采用美国脊髓损伤学会制定的评分标准,进行术前和术后评分对比。结果:47例患者均进入结果分析。许旺细胞移植后8周时,按美国脊髓损伤学会脊髓损伤神经功能分类国际标准评价,47例患者的脊髓功能均有部分恢复,与术前对比,差异有显著性意义[术前:运动功能:(41.30±16.48)分,轻触觉:(56.28±21.04)分,针刺觉:(58.47±23.12)分;术后:运动功能:(44.06±17.030分,轻触觉:(60.38±20.52)分,针刺觉:(65.30±23.73)分,P<0.05)。患者术后无发热、脊髓感染、功能损伤加重及死亡等并发症。术后复查磁共振检查脊髓无瘤样增生及空洞扩大。结论:本实验应用的手术方法移植许旺细胞治疗晚期脊髓损伤具有安全性,术后8周评估患者脊髓功能与术前比较有量化性提高,其恢复部分脊髓神经功能的作用尚需原期观察。

关键词：细胞移植脊髓损伤外科手术

High Manganese Steel Alloying Process and Its Influence on Microstructure and Properties of the Steel

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Journal of Materials Science & Technology 1995年第2期11卷 102-108页

作者： SHI, ZL GU, MY liu, JY YIN, ys HEBEI INST MECH ELECT DEPT MAT SCI & ENGNSHIJIAZHUANGPEOPLES R CHINA DALIAN UNIV TECHNOL DEPT MAT SCI & ENGNDALIAN 116023PEOPLES R CHINA

The influence of two kinds of alloying processes, adding Nb (or Ti) and N-Mn alloy as well as adding Nb (or Ti) and spraying Nz, on microstructures and properties of a high manganese steel has been studied. It has been found that adding Nb(or Ti), accompanying with N-Mn alloy, is unfavourable to microstructure compactness of the high manganese steel, but adding Nb (or Ti) and spraying N-2 into the melt is good for refining austenitic grain, forming a lot of hard particles and improving microstructure compactness. The mechanical properties of the high manganese steel have relation to the content of elements Nb or Ti. Its fracture mode will turn ductile fracture into brittle cleavage fracture gradually By X-ray and TEM analysis, it is proved that the austenite can be transformed to deformation-induced cr martensite after adding a certain amount of element Nb (or Ti). The microstructure transformation of alloying high manganese steels through deformation is one of methods for strengthening austenite matrix acid increasing the work-hardening rate as well as improving antiwear property.

关键词： Alloying

Active oxygen radical scavenging ability of water-soluble fullerenols

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Chinese Science Bulletin 1997年第9期42卷 748-752页

作者： Sun, DY Zhu, ys liu, ZY liu, GZ Guo, XH Zhan, RY liu, XY State Key Laboratory of Applied Spectroscopy Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China

THE bioactivity study of C60 and its relative derivatives is of considerable ***60 itself is a non-polar molecule and very difficult to dissolve in common polar solvents,its ap-plication in biochemistry field is greatly *** preparation of some water-solubleC60 derivatives will be *** found that a water-soluble C60 derivative,[HOCO-

关键词： C60 fullerenols active-oxygen-radical ESR spin trapping.

Measurement and Calculation of Quenching Rate Constants for PCl(b)

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Chinese Chemical Letters 1996年第12期7卷 1125-1126页

作者： Zou, SL liu, CP Guo, JZ Gu, ys Chu, YN Cao, DZ SHANDONG UNIV DEPT CHEMJINAN 250100PEOPLES R CHINA ACAD SINICA ANHUI INST OPT & FINE MECHLASER SPECT LABHEFEI 230031PEOPLES R CHINA

Using the Ar(P-3(0.2)) +PCl3 reaction as a source of PCl(b(1) Sigma(+)). We have measured the quenching rate constants of PCl(b) for 23 reagents. The E -V model is used to calculate the rate constants. The comparison ... 详细信息

关键词： Measurement and Calculation of Quenching Rate Constants for PCl

Neutron-irradiated Si by positron annihilation

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Chinese Science Bulletin 1997年第1期42卷 26-30页

作者： Huang, MR Wang, YY Yang, JH He, ys Guo, YH liu, CC Institute of High Energy Physics Chines Academy of Sciences Beijing China Research Laboratory of Semiconductors Hebei Technological College Tianjing China

SILICON is a quite important material in the application of energy resources technology. With the development of ion-implantation technique and the increasing interest in dopping, it is very important to know the relationship between the vacacies induced by the particle irradiation damage and the annealing temperature. The positron annihilation is a very useful method for studying defects in the semiconductor, because the annihilation characteristics of trapped positron are influenced by the charge of the defects. It has been shown that the positrons can be trapped by defects created by irradi-

关键词： neutron-irradiated Si positron annihilation vacancy.

Physiological responses of four herbaceous plants to aluminum stress in South China

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Frontiers in Biology 2006年第3期1卷 295-302页

作者： liu Peng YANG ys XU Gendi GUO Shuiliang ZHENG Xiaobin WANG Min Key Laboratory of Botany Zhejiang Normal UniversityJinhua 321004China Environmental Engineering Research Centre The Queen’s University BelfastBelfast BT95AGUK

Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al *** aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants,which distributed in red soil area in South China,and to analyze the differences in physiological responses to Al stress between the four herbaceous *** herbaceous plants(Pharbitis nil,Cassia occidentlis,Echinochloa colonum and Aeschynomene indica)were used,and the seed germi-nation percentage,the contents of chlorophyll,proline,and malondialdehyde(MDA),membrane permeability(MP),soluble sugar,and activities of peroxides(POD)and cata-lase(CAT)in leaves under five Al^(3+)treatments(0,80,400,2000,and 10000 mg/L)were assayed with the sand culture *** results showed remarkable effects of Al^(3+)on physiological characteristics of these four herbaceous *** seeds of all the four species could not germinate at 10000 mg/L,and the growth of all plants were retarded under the 2000 mg/L Al^(3+)*** with the control,2000 mg/L Al^(3+)significantly(P<0.05)reduced the con-tents of chlorophyll a and chlorophyll a+b,and increased the contents of MDA and *** content of proline in-creased very significantly(P<0.01)and activities of POD and CAT were *** contents of MDA and MP in leaves of *** and *** decreased,and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/***,the changes in *** leaves were opposite to those of the above two *** changes in leaves of *** were similar to those of *** and *** at 80 mg/L,but were opposite to those at 400 mg/L Al^(3+).It is suggested that plants with higher ac-tivities of POD and CAT,more contents of chlorophyll and proline,and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.

关键词： aluminium stress physiological and ecological response tolerance seed germination herbaceous plants

Evaluation of various solutions for small bowel graft preservation

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World Journal of Gastroenterology 1998年第2期4卷 48-51页

作者： Li ys Li JS Li N Jiang ZW Zhao YZ Li NY liu FN

AIM To elucidate the effect of various solutions for small bowel graft preservation in pigs under hypothermic storage. METHODS The swine segmental small bowel graft was autotransplanted after it was preserved with lactated Ringer′s (LR), Euro Collins (EC), hyperosmolarity citrate adenine (HC A) and WMO 1 solutions for 10, 18 and 24 hours, respectively. The recipient survival rate, morphological structure, graft mucosal energy substances and Na + K + ATPase activity were studied, and graft absorption was estimated with D xylose absorption test. RESULTS The morphological study of the grafts preserved with LR or HC A solution for 10 hours or with EC and WMO 1 solution for 18 hours was normal 6 days after operation. Mucosal ATP, total adenine nucleotides (TAN) contents and Na + K + ATPase activity of the graft preserved with EC or WMO solution were higher than that of the graft preserved with LR or HC A solution. Serum level of D xylose was higher in EC and WMO 1 groups than in LR and HC A groups when the graft was preserved for 24 hours. CONCLUSIONS EC and WMO 1 solutions can preserve the swine small bowel up to 18 hours, which are superior to LR and HC A solutions.

关键词： intestine, small/transplantation organ preservation adenosine triphosphate intestine, small/transplatation Na(+) K(+) exchanging ATPase adenine nucleotides