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排序方式: 共有7127条查询结果,搜索用时 15 毫秒
61.
目的 比较短期化疗前后兔腹主动脉顺应性的变化,了解化疗药物对血管力学特性的影响。方法将15只新西兰兔随机等分为5组,其中4组接受1周期化疗(卡铂100mg/m^2,第1、3、5天;异环磷酰胺1500mg/m^2,第1、3、5天;足叶乙贰100mg/m^2,第l~3天),另1组为对照组。分别测量各组兔腹主动脉比顺应性(化疗组分为化疗后第2、7、14、21天进行观察)。结果短期化疗前后兔腹主动脉顺应性显著变化,化疗后第14天下降最明显,而第21天则基本恢复。结论短期化疗能够降低兔腹主动脉比顺应性,降低的程度与化疗后时间相关,并具有可逆行性。 相似文献
62.
深低温冷冻保存家兔性腺器官的研究 总被引:6,自引:0,他引:6
自1992年7月开始行深低温(-196℃)冷冻保存兔性腺研究。冷冻睾丸36个,15天后解冻,完好率91.7%,其中20个行器官移植,睾丸接通血管均即时建立血循环。4只兔的冷冻睾丸自体移植后,每次采精740.6±1890.4万个。2只兔的冷冻睾丸异体移植后,每次采精63.4±37.7万个。冷冻兔卵巢14个,15天后解冻,完好率92.9%,其中8个行器官移植,卵巢接通血管均即时建立血循环,术后雌二醇水平为2.72~127.3pmol/L。冷冻睾丸及卵巢移植一段时间后病理切片证实睾丸及卵巢组织存活。 相似文献
63.
The Use of Stent Grafts for the Treatment of Aneurysms and Dissections of the Thoracic Aorta: A Single Centre Experience 总被引:5,自引:0,他引:5
P. Matravers R. Morgan A. Belli 《European journal of vascular and endovascular surgery》2003,26(6):587-595
OBJECTIVE: To review the results of stent graft treatment for diseases of the thoracic aorta. DESIGN: A retrospective study of the results of thoracic stent graft procedures in a single centre. METHODS: The results of 30 procedures performed in 24 patients were analysed. Eleven patients had aneurysmal dilatation of the descending thoracic aorta (>5.5 cm), nine patients had complicated type B dissection, three had penetrating ulcers and one had a traumatic pseudoaneurysm. Imaging follow-up consisted of CT scans performed at one, three, six and 12 months following the procedure and annually thereafter. RESULTS: One technical failure occurred due to a ruptured external iliac artery. There were no other immediate failures. The primary technical success rate was 83%. The 30-day procedural and patient mortality rates were 7 and 8%, respectively. No neurological complications occurred. Seven patients had the subclavian artery covered without complications. Secondary intervention was required in 21%. During the follow-up period (mean 11 months, range 1-48 months.) there were five deaths, two of which were related to stent graft infection. CONCLUSION: Thoracic stent grafts offer a realistic alternative to surgery. 相似文献
64.
J. W. Constantine W. S. Lebel H. A. Woody 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(6):722-724
Summary Neurokinin A, neurokinin B and substance P caused concentration-related contractions of rabbit isolated aorta with pD2 values of 8.1, 6.9 and 6.0, respectively. [D-Pro2, D-Trp7,9]-substance P, a competitive tachykinin antagonist, had pA2 values of 5.3 against neurokinin A, 5.1 against neurokinin B and 5.2 against substance P indicating that tachykinin receptors
mediated responses to the agonists. [pGIu5,MePhe8,-McGly9]-substance P 5–11 (DiMe-C7), senktide and septide did not contract the aorta. It is concluded that of the known tachykinin
receptors smooth muscle of the rabbit isolated aorta contains only the NK-2 type.
Send offprint requests to J. W. Constantine at the above address 相似文献
65.
将Wistar大鼠随机分成氧化胆固醇组(Och)、纯胆固醇组(Pch)和对照组,分别用氧化胆固醇混合物(250mg/kg bw/d)、纯胆固醇(250mg/kg bw/d)以及悬浮固醇用的明胶液体给大鼠灌胃,连续二天。于第二次灌胃后18小时,从大鼠尾静脉注射伊文思兰溶液,并于注射后2小时处死;取出主动脉用荧光显微分光光度术测定主动脉内膜的通透性。此外,另一部分动物在第二次灌胃后24小时处死,取出主动脉作扫描电镜的内膜观察。结果表明,Och大鼠主动脉内膜的通透性显著高于Pch组与对照组大鼠(P<0.01),而Pch组大鼠主动脉内膜的通透性和对照组无显著差异(P>0.05)。 相似文献
66.
体外冲击波对兔输尿管形态及组织学影响的研究 总被引:13,自引:0,他引:13
目的 :探讨冲击波 (SW )对输尿管形态的影响。方法 :将 4 2只成年兔随机分为 7组 ,每组 6只。第 1组为正常对照组 ;第 2~ 6组为液电式SW组 ;第 7组为电磁式SW组。各组接受冲击并在冲击后不同时间取材。全部标本行常规病理检查并予评分。结果 :第 2~ 5组和第 7组 ,肉眼可见焦点周围组织有出血、水肿等改变 ,输尿管直径较冲击前显著增加 (P <0 .0 1 )。光镜下可见平滑肌细胞变性及管腔狭窄 ,病理量化评分显著高于正常组 (P <0 .0 5 ) ;电镜下则有肌细胞线粒体破坏等改变。第 6组形态改变不明显 ,病理评分和正常组的区别无显著性意义。结论 :临床剂量的冲击波能导致输尿管多种病理变化。冲击后第 5天 ,输尿管形态已基本恢复正常。由液电式和电磁式冲击波所致的输尿管急性损伤程度无明显的区别 相似文献
67.
Hyett Jon; Moscoso Gonzalo; Nicolaides Kypros 《Human reproduction (Oxford, England)》1995,10(11):3045-3048
Pathological examination of the heart and great vessels wasperformed in 61 specimens obtained after surgical terminationof pregnancy for psychosocial indications at 918 weeksof gestation. The aorta and pulmonary trunk were identifiedand external diameters were measured at the level of, and distalto the aortic valve and pulmonary valve, the level of the aorticisthmus and thoracic aorta, and the proximal and distal ductusarteriosus. All eight vessel diameters increased linearly withgestational age and the ratio of the diameter of the aorticisthmus to that of the aortic valve or the distal ductus arteriosusalso increased with gestation. Early pregnancy is characterizedby rapid growth of the fetal head and this may well be the consequenceof a preferential distribution of left ventricular output infavour of the head due to relative narrowing of the aortic isthmusat this gestation. 相似文献
68.
微囊胎垂体下丘脑黑质细胞移植实验研究 总被引:1,自引:0,他引:1
微囊包膜的股垂体下丘脑黑质细胞移植于去垂体兔腹腔中,术后观察移植兔12周。结果:移植后兔血清中GH与PRL浓度可平稳在一定水平,T4浓度自第2周起开始上升并逐渐接近正常水平,兔体重于第3周起开始增加,各靶器官在12周后无明显萎缩。提示本微囊可在促垂体区(HTA)以外移植而重建正常垂体功能达12周以上。 相似文献
69.
N. H. Staalsen J. M. Hasenkam J. Winther M. Ulrich E. M. Pedersen 《Heart and vessels》1993,8(4):194-202
Summary Earlier studies using hot-film anemometry in pigs have revealed skewed tangentially rotating velocity profiles in the ascending aorta during systole. The reason for this phenomenon has been postulated to be caused by the left ventricular contraction pattern. Therefore, the aim of this study was to investigate the influence of the left ventricular contraction pattern on the velocity fields in the ascending aorta of pigs. We used a 10 MHz perivascular pulsed Doppler ultrasound system to measure point blood velocities at two axial locations over the entire cross sectional area in the ascending aorta of 90 kg pigs. The axial component of the velocity profiles was visualized dynamically by computerized 3-dimensional animation techniques. Changing left ventricular contraction patterns were accomplished by reversible occlusion of either the left anterior descending or right posterior descending coronary artery. The axial development of the systolic rotating and skewed velocity profiles in the ascending aorta was described. The appearance of the systolic velocity profiles were virtually unaffected by changes in left ventricular contraction pattern.This study was kindly supported by The Danish Heart Foundation, Civilingeniør Frode Nyegaard og Hustru's Fond and NOVO's Forskningsfond 相似文献
70.
消炎痛对hCG诱发家兔排卵抑制的形态学研究 总被引:3,自引:0,他引:3
应用非甾体抗炎药消炎痛(20mg/kg)抑制hCG 诱发的家兔排卵,注射后的6、9、12、72小时剖腹观察排卵数,并取材进行透射电镜观察和酶组织化学观察。甾体激素合成酶类的组织化学和颗粒细胞内某些细胞器的电镜立体定量学测定结果表明:消炎痛抑制了排卵,却不影响颗粒细胞向黄体细胞的转变。透射电镜观察表明:在排卵前,实验组和对照组最明显的不同是:实验组的外膜和白膜很少见到胶原溶解现象,且表面上皮细胞内含的致密小体不释放其内容物。结果提示:消炎痛主要作用于排卵前卵泡顶部的成纤维细胞和表面上皮细胞,这可能与其抑制了某些与排卵有关的酶的释放有关。 相似文献