可膨式金属胆道支架在肝门部胆管癌的临床应用及疗效

目的探讨可膨式金属胆道支架对肝门部胆管癌的疗效及影响因素。方法32例肝门部胆管癌患者先通过内镜下逆行胰胆管造影(ERCP)放置可膨式金属胆道支架,ERCP不成功则通过经皮经肝胆道引流(PTCD)窦道放置。观察其操作成功率、退黄效果、并发症发生情况、支架通畅期及患者生存期。结果32例患者中28例均成功通过ERCP置入可膨式金属支架,3例改行PTCD后再经窦道放入金属支架,成功率96.88%,1例行两种处理方法均未能成功;所有患者术后黄疸明显减退;3例患者支架再次阻塞,1例患者反复发作胆管炎,并发症发生率为12.5%;支架平均通畅期为213d,患者平均生存期为235d。结论可膨式金属胆道支架创伤小,通畅性能好,可作为无法手术切除或不愿手术的肝门部胆管癌患者的首选治疗方法。

可膨化石墨／低密度聚乙烯导电复合材料的制备及性能研究

选用可膨化石墨（EGP）和低密度聚乙烯（LDPE）制备了一种导电复合材料，并系统研究了LDPE／EGP复合材料的电学、力学性能以及正温度系数（PTC）效应。实验结果表明，随着EGP用量的增加，复合材料的拉伸强度升高，弹性形变减少，为保证复合材料的力学性能，EGP的最大填充量应低于40％。加入一定比例的EGP后，纯LDPE电阻率降低了近6个数量级。随着EGP含量的增加，复合材料的PTC强度先增加后降低。当EGP含量介于30％～35％之间时，复合材料的PTC强度达到最大值，最大值约为5．85。选择合适的热处理温度和密炼时间，可获得具有较高PTC强度的复合材料。

目击正规性和可膨性(英文)

本文将Tall引入的目击正规性这一概念推广到目击各种可膨性,并在连续统假设或弱连续统假设之下讨论了它们之间的关系。

关于可缩性与可膨性的一些注记

本文证明了正规θ－加细空间具有弱β性质，还证明了在正则可膨空间，仿紧性与性质弱ｂ１等价。

腰椎融合修复中可膨胀式融合器的应用

微创化、智能化、功能化是目前外科发展的一种趋势，侧路椎间孔镜下腰椎摘除是目前腰椎间盘微创手术的代表，在临床上取得了满意的疗效，但是对于腰椎间盘突出伴腰椎管狭窄、腰椎不稳定的病例，疗效差，随着研究的不断深入，该项技术联合腰椎融合术必将取代传统的开放手术，减少创伤，减少复发，减少不必要的腰椎椎旁肌损伤。

可膨式金属胆道支架解除恶性胆管梗阻的临床应用及其疗效分析

目的探讨可膨式金属胆道支架术解除恶性胆管梗阻的中远期疗效及初步分析影响疗效的因素。方法１３４例各类恶性肿瘤导致胆管梗阻的患者接受金属支架放置术，其中内镜下经乳头放置１２８例，经皮经肝放置６例，随访引流效果并与同期９７例内镜下放置塑料支架的患者进行对比。结果操作成功率９５７％，并发症６４％，黄疸消除率８５６％，金属支架的平均通畅期为３００天，明显高于塑料支架的８０天（Ｐ＜００１）；平均存活期为２１０天。原发性胆管肿瘤的支架通畅性与继发性肿瘤接近，而平均生存期略长；高位胆管梗阻的支架通畅期和存活期与中低位梗阻相仿。结论可膨式金属胆道支架的平均通畅性能显著优于普通塑料支架，提高疗效的关键是严格掌握适应证。

胡桃夹征致左侧精索静脉曲张的介入治疗

目的探讨胡桃夹征（NCS）致左侧精索静脉曲张的诊断与治疗。方法回顾性分析12例胡桃夹征致左侧精索静脉曲张患者的临床资料。12例患者均采用左肾静脉造影＋支架置入术治疗，术前、术后分别经彩色多普勒超声显像、选择性左肾静脉造影和（或）CT及MRI等检查。结果术后左肾静脉狭窄管腔扩张，血流恢复通畅。术前彩超显示左肾静脉狭窄段内径为1．1-2．9mm，平均（2．1±0．2）mm，术后为4．8—8．0mm，平均（6．5±0．6）mm（t=10．74，P=0．00）；术前狭窄段血流速度为44—200cm／s，平均为（108．0±31．6）cm／s，术后22—49cm／s，平均为（33．3±4．15）cm／s（t=4．58，P=0．00），均有统计学意义。除1例患者术后复查仍表现为左精索静脉曲张外，其余患者精索静脉反流消失，5例血尿及2例蛋白尿患者术后1周复查尿常规正常。结论经皮左肾静脉支架置入术创伤小，住院时间短，近期效果明显，我们认为是目前治疗左肾静脉压迫综合征的首选方法，但远期效果有待观察。

恶性胆道梗阻的经皮胆道介入治疗

目的 探讨如何改进恶性胆道梗阻的介入治疗。方法 对 35例确诊为恶性胆道梗阻的患者 ,先经皮肝穿刺胆道造影确定梗阻部位 ,再选择合适的胆管穿刺 ,置入导丝至十二指肠 ,经导丝放置引流管行胆道内外引流。其中 6例立即放置可膨式金属支架 ,8例 2周后放置。结果 3例术后1个月后死亡 ,其余术后血胆红素、碱性磷酸酶和谷丙转氨酶较术前下降明显。随访 32例 ,6个月生存率占 5 6 %。结论 对于恶性梗阻性黄疸 ,经皮胆道介入治疗能延长生存时间 ,减轻痛苦 。

Rapid microwave irradiation fast preparation and characterization of few-layer graphenes

Few-layer graphenes were fabricated from expandable graphite by rapid microwave exfoliation. Expandable graphite was irradiated in a domestic microwave in full power for 3 min, then soaked in mixed strong hydrogen nitrate and sulfuric acid with volume ratio of 1：1 for 24 h and re-irradiated, thus few-layer graphene sheets were obtained. Specimens gained from every step were selectively characterized by different techniques, such as SEM, XRD, Raman, AFM, XPS, FTIR and combustion elemental analysis. The results show that expandable graphite with loose, porous and worm-like morphology forms instantaneously in microwave irradiation with crackling sound and sparkles, which manifests physical exfoliation of graphene sheets. Few-layer graphene sheets with a dozen or more layers and average thickness of about 4.7 nm are obtained eventually after sequential treatment of microwave irradiation, mixed acid soaking and second microwave irradiation. The as-prepared few-layer graphenes still have high crystallinity and high purity with traces of oxide groups and without serious unrecoverable oxidation damage.

Comparison of different intervention procedures in benign stricture of gastrointestinal tract

AIM:To determine the most effective intervention procedure by evaluation of mid and long-term therapeutic efficacy in patients of stricture of the gastrointestinal tract (GTT). METHODS:Different intervention procedures were used to treat benign stricture of GIT in 180 patients including pneumatic dilation (group A,n=80),permanent (group B, n=25) and temporary (group C,n=75) placement of expandable metallic stents. RESULTS:The diameters of the strictured GIT were significantly greater after the treatment of all procedures employed (P<0.01).For the 80 patients in group A,160 dilations were performed (mean,2.0 times per patient). Complications in group A included chest pain (n=20),reflux (n=16),and bleeding (n=6).Dysphagia relapse occurred in 24(30%) and 48 (60%) patients respectively during 6-and- 12 momth follow-up periods in group A.In group B,25 uncovered or partially covered or antireflux covered expandable metallic stents were placed permantly, complications included chest pain (n=10),reflux (n=15), bleeding (n=3),and stent migration (n=4),and dysphagia relapse occurred in 5 (20%) and 3 patients (25%) during the 6-and-12 month follow-up periods,respectively.In group C,the partially covered expandable metallic stents were temporarily placed in 75 patients and removed after 3 to 7 days via gastroscope,complications including chest pain (n=30),reflux (n=9),and bleeding (n=12),and dysphagia relapse occurred in 9 (12%) and 8 patients (16%) during the 6-and-12 month follow-up periods,respectively.The placement and withdrawal of stents were all successfully performed.The follow-up of all patients lasted for 6 to 96 months (mean 45.3±18.6 months). CONCLUSION:The effective procedures for benign GIT stricture are pneumatic dilation and temporary placement of partially-covered expandable metallic stents.Temporary placement of partially-covered expandable metallic stents is one of the best methods for benign GIT strictures in mid and long-term therapeutic efficacy.

Potentially fatal haemobilia due to inappropriate use of an expanding biliary stent

AIM: To highlight the fatal complication caused by expanding biliary stents and the importance of avoiding use of expanding stent in potentially curable diseases.METHODS: Arteriobiliary fistula is an uncommon cause of haemobilia. We describe a case of right hepatic artery pseudoaneurysm causing arteriobiliary fistula and presenting as severe malena and cholangitis, in a patient with a mesh metal biliary stent. The patient had lymphoma causing bile duct obstruction.RESULTS: Gastroduodenoscopy failed to establish the exact source of bleeding and hepatic artery angiography and selective embolisation of the pseudo aneurysm successfully controlled the bleeding.CONCLUSION: Bleeding from the pseudo aneurysm of the hepatic artery can be fatal. Mesh metal stents in biliary tree can cause this complication as demonstrated in this case.So mesh metal stent insertion should be avoided in potentially benign or in curable conditions. Difficulty in diagnosis and management is discussed along with the review of the literature.

Analysis of effect of pressure on surface accuracy for inflatable antenna

Pressure is one of the important measures to control the surface accuracy of the reflector of inflatable antenna. Experiments and numerical analysis were carried out to highlight the effect of pressure on accuracy. The rapid, contactless and low-cost digital photogrammetry system （DIES） was employed to investigate the effect according to its lightweight and flexible characteristics. Measurement data show that the best pressure and the best area in this pressure can be obtained. Numerical analysis was conducted to check the measurement result. It is indicated that there is a little difference between them attributed to wrinkle. Results of analysis and experiments show that surface accuracy of the reflector can be adjusted by controlling pressure.

Effect of dosage of expandable graphite,dimethyl methylphosphonate,triethanolamine,and isocyanate on fluidity,mechanical,and flame retardant properties of polyurethane materials in coal reinforcement

In this study,orthogonal experiments were conducted to investigate the influence of expandable graphite(EG),dimethyl methylphosphonate(DMMP),triethanolamine(TEA),and isocyanate content on the compressive and bonding strengths,oxygen index,and fluidity of rigid polyurethane foam(RPUF).The results revealed that EG significantly increased the oxygen index of RPUF,enlarged the diameter of foam cells,and decreased the cell-closed content in foam;thus,leading to a pressure drop in RPUF.However,excessive EG was capable of reducing the fluidity of polyurethane slurry.TEA exhibited significant influence on the compressive strength of RPUF,which dropped initially,and then increased.DMMP had a remarkable effect on the flame retardant property and compressive strength of RPUF.Compressive strength of RPUF initially displayed an increase followed by a decrease with increasing dosage of DMMP,and achieved the maximum value at DMMP dosage of 4%.DMMP could effectively reduce the diameter of RPUF cells leading to an increase in the percentage of close area in foam.DMMP displayed the flame-retardation effects mainly in the gas phase leading to a significant enhancement in the oxygen index of RPUF.Moreover,the compressive strength and bonding strength of RPUF decrease significantly with the increase of isocyanate content due to the increased blowing efficiency by the CO_2.The oxygen index and flowing length of foam increased with the increase in isocyanate dosage.

Experiment research on mechanical behavior of the aluminum laminate in the low-high temperature

Aluminum laminate is one kind of the rigidizable composite materials and plays an important role in construction of the inflatable space structure(ISS),which has potential application in space in the future.But the study of the predecessors mainly focuses on the research of the mechanical behavior in the room temperature,for this reason,mechanical properties of the aluminum laminate in low-high temperature have been studied in this paper.The failure mechanism of the aluminum laminate is also analyzed in the microscopic view by JCXA-T33 electron probe.The results show uhat the temperature has significant influence on the strength and Young's modulus of the aluminum laminate.With the increase of temperature,both the strength and Young's modulus of the aluminum laminate decrease.A model between Young's modulus of the aluminum laminate and temperatures is obtained by using Arrhenius equation.The predicted values by the model agree well with the experiment values.

Research on improving the system of account rate in occupational pension

In the reform of government organizations and institutions of China, we put forward the establishment of personal account system in occupational pension, and the introduction of the ＂account＂ management model of the non real account accumulation. This paper analyzes the current situation of personal accounts in our country, and puts forward that the account rate of bank deposit can not resist inflation, and can not reflect the real return rate of China＇s pension funds, which is not conducive to the preservation and appreciation of personal account funds. On the basis of the above, the paper puts forward that the account rate should not only consider the level of economic development and inflation, but also to adapt to the financial payment ability, and establish the personal account risk reserve fund system and other improvement measures, and strive to achieve the sustainable development of the personal account system.

手术方式与肝门部胆管癌预后的关系分析

目的研究影响肝门部胆管癌预后的因素,探讨手术方式与肝门部胆管癌预后的关系。方法对1997年12月至2002年12月收治的198例肝门部胆管癌资料进行回顾性队列研究。男性117例,女性81例。年龄27～81岁,平均56岁。黄疸(94.5%)、瘙痒(56.6%)和腹痛(33.8%)为主要症状。BismuthCorlette分型:Ⅰ型14例,Ⅱ型19例,Ⅲa型12例,Ⅲb型15例,Ⅳ型112例,分型不清楚者26例。手术治疗144例,120例(83.3%)获得切除,其中根治性切除59例(41.0%)。胆道探查置管引流24例。单纯内镜逆行内置管胆道引流(ERBD)或经内镜放置可膨式金属胆道支架(EMBE)21例,内镜鼻胆管引流(ENBD)31例,经皮经肝胆道引流2例。结果Cox模型分析结果显示术后生存时间与职业、术前最高血清总胆红素水平、手术方式和术后放疗四个因素显著相关,与以下因素关系不显著:性别、年龄、是否合并胆石、是否合并肝炎、术前CA199水平、BismuthCorlette分型、肿瘤分化程度和是否术后化疗。胆道置管引流、肿瘤姑息性切除、根治性切除组的术后生存期之间,两两比较均存在统计学差异。ERBD或EMBE组与姑息性切除组或与开腹胆道置管引流组之间,以及ENBD组与开腹胆道置管引流组间差异无统计学意义,ERBD或EMBE组与ENBD组间差异有统计学意义。结论手术方式是肝门胆管癌最重要的预后因素,根治性切除仍然是患者获得治愈和长期生存最重要的措施。对于无法根治切除的肝门胆管癌,尚不能认为ERBD或EMBE比开腹手术治疗的疗效差。

内镜下同期放置双侧金属胆道支架的方法探讨

目的 探讨经内镜同期置入双侧可膨式金属胆道支架的方法。方法9例Ⅱ～Ⅳ型肝门部胆管恶性梗阻患者，平均血胆红素（162．8±193．8）μmol／L，内镜下插入双导丝分别留置在左、右侧胆管内，在充分扩张狭窄段后，逐一插入金属支架至双侧肝管予以释放。观察操作的便利性、成功率、控制黄疸有效性、早期并发症和近期的临床疗效。结果全组均一次成功置入双侧支架，分别采用“Y”型支架置入法2例、塑料支架过渡法1例和并行支架法6例，平均耗时（38．1±14．8）min，以并行法置入且留置支架末端在乳头外的方法最为便捷。9例患者术后除1例外其他黄疸均迅速消退，3周内均退至正常，无明显并发症发生。结论同期置人双侧金属支架是安全可行的，可迅速有效地控制肝门部肿瘤所致的黄疸和胆道感染；采用特殊设计的金属支架并行置入，并将支架末端留置在乳头外，是较为简便效佳的方法。

改良金属支架在胃出口恶性梗阻中的应用

1992年Topazian等报道用金属支架扩张治疗胃出口恶性梗阻取得成功，之后国内外相继有多篇采用可膨式金属支架治疗胃出口梗阻的报道，但多数仍采用普通的食管或肠道支架来代替，其支架的口侧端口并无特殊设计，支架的胃内部分多不能与胃窦残腔壁贴合。近年来，随着制造丁艺的日益成熟，通过对金属支架个体化设计和制作，使其更适合胃窦的解剖和生理。本研究根据部分患者胃出口恶性梗阻患者残存胃窦腔呈卜宽下窄的形状以及残存胃窦腔口侧端胃腔直径宽大的特点对金属支架的口侧端口进行了设计（国家专利号：IL200720105871．5），治疗11例患者。