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51.
目的:建立大鼠颈动脉再狭窄模型,原位灌注固定取材。评价PTA后血管重塑(VR)的动态变化规律,定量分析血管重塑在血管再狭窄过程中的变化及作用。方法:制作70只SD雄性大鼠颈总动脉再狭窄模型,分原位灌注实验组、对照组,于术后1h、3、7、14、28和42天原位灌注固定取材,行HE染色、Masson染色,观察标本血管狭窄情况。结果:①血管重塑指数(VRI)在PTA后即刻最大,3天组明显降低,7天组稍有增大,其后不断减小,剩余血管腔面积百分比同VRI的变化曲线基本一致。②FFA后,血管腔面积总体呈逐渐缩小趋势,内弹力板围绕面积(IELA)1h组较对照组明显增大,3天组较1h组明显缩小,14、28、42天组较对照组明显缩小。外弹力板围绕面积(EELA)逐渐缩小。EELA、IELA的变化与血管腔面积变化呈正相关。③VRI与血管腔面积的变化呈正相关,新生内膜面积与剩余狭窄率、血管腔面积无直线相关。结论:再狭窄过程中存在扩张性重塑和收缩性重塑现象,管腔的狭窄与否取决于血管重塑指数的变化,而不是新生内膜的变化,新生内膜的形成是血管重塑过程中的一部分。IELA和EELA可作为判断管腔狭窄及评价血管重塑的指标。 相似文献
52.
C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献
53.
Summary The monocrofaline-induced structural changes of small pulmonary arteries in rat and their relationship with pulmonary hypertension
and right ventricular hypertrophy were observed by determining the right ventricular systolic pressure, and by light and electron
microscope and morphometry. One to 38 days after last injection of monocrotaline (MCT), a medial thickening and lumen marrrowing
of the circular muscular arteries (CMA), accompanying terminal (TB) and respiratory bronchioles (RB), were found. And there
after the lumen of CMA, accompanying TB, became dilated, and its medial thickness (MT) decreased, whereas the histopathologic
changes of the partially muscular arteries (PMA), accompanying RB, became severe, their MT increased continuously, and finally
reached the peak value on Day 50. At the first day after last MCT treatment, inflammation and muscularization were found in
PMA and nonmuscular arteries (NMA), and became more severe with the cause of disease. Therefore, the intra-acinar pulmonary
arteries, both CMA and PMA, increased in number while the NMA decreased in number significantly because of the structural
remodeling. Four days after MCT treatment, the right ventricular systolic pressure began to rise, and reached its peak value
on Day 50. Eight days after MCT injection, right ventricular hypertrophy developed, and became most significant from Day 23
to Day 30. The results suggest that structural remodeling, i.e. muscularization, of intra-acinar pulmonary arteries plays
an important role in the development of pulmonary hypertension and right ventricular hypertrophy. 相似文献
54.
Preexpanded distant "super-thin" intercostal perforator flaps for facial reconstruction without the need for microsurgery. 总被引:1,自引:0,他引:1
F Lu J H Gao R Ogawa H Hykusoku 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(11):1203-1208
BACKGROUND: Concept of the 'super-thin perforator flap' was introduced in 1994 by authors. Since then, various types of 'super-thin perforator flaps' were applied successfully especially for contour sensitive reconstruction such as face and neck. METHODS: Eleven patients requiring large flaps who presented with extensive disfiguring facial scar (male: seven cases, female: four cases). On the consideration of flaps' colour, texture and thickness requirements, the authors selected 'super-thin' anterior intercostal perforator flaps (AICP, range from 4 x 14 cm to 25 cm x 9 cm) for reconstruction purpose. First, tissue expanders (volume range from 800 cc to 1200 cc) were carefully inserted under the AICP. After the flaps were expanded for 2 months, distant scars were removed and the covering super-thinned flaps were transferred into recipient site. Two weeks later, pedicles in the anterior chest were cut down and flaps were transferred to replace all the left scars. RESULTS: Flap were survived without any complications. The colour, texture and thickness of the transferred flap were satisfactory, shrink of flaps were not observed after long term follow-up. The authors present a method of facial reconstruction that has the advantages of creating a large amount of thin tissue of both good colour and texture, without the need of microsurgery and few disadvantages of donor-site morbidity. The disadvantages are three-staged procedures, complications of tissue expansion and uncomfortable compulsory posture for patients. In our opinion, this is an alternative method of choice for reconstructing all large defects in the lower two-thirds of the face. 相似文献
55.
Haemodynamic studies in early stroke 总被引:2,自引:0,他引:2
Summary We investigated prospectively a consecutive series of 81 patients suffering from acute middle cerebral artery (MCA) ischaemia by transcranial Doppler ultrasonography (TCD) within 24 h of the onset of symptoms. To monitor the haemodynamic changes follow-up recordings were carried out at short intervals during the next 2–3 weeks until stable haemodynamic status was achieved. In order to estimate the value of early TCD examinations in predicting the extent of brain damage seen later on, initial MCA flow reduction was correlated with infarction size and pattern on computed tomography. Fifty-three cases showed sufficient ultrasound penetration through the temporal bone. MCA flow asymmetries were recorded in 45 patients (85%); occlusion was observed in 17. Recanalization occurred in 11 patients followed by transient hyperaemia in 3, leaving residual stenosis in 2. Initial increase of flow velocities normalized within days or weeks in 7 out of 9 patients, while 2 developed residual MCA stenosis. Nineteen patients showed a considerable flow reduction on admission, which returned to normal in 9; transient hyperaemia was detected in 5 of these. Eight patients did not show any MCA flow asymmetry. Our study revealed very variable haemodynamic changes in acute stroke, which influenced further diagnostic and therapeutic management. The high rate of spontaneous recanalizations of MCA occlusions followed by transient hyperaemia in many cases has an important bearing on thrombolytic or theological therapy. Flow velocity differences could be related to infarction pattern rather than to infarction volume. Early MCA flow asymmetry recorded by TCD within the first 24 h could not reliably predict the extent of persistent brain damage or clinical outcome. 相似文献
56.
支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 总被引:1,自引:1,他引:0
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法 76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高 相似文献
57.
在耳鼻咽喉科手术中应用颈外动脉栓塞法10例,形成栓塞组,并把单纯颈外动脉结扎10例作为对照组。结果表明:栓塞组较对照组术中出血量显著减少,有利于病灶彻底清除,因而有提高治愈率减少复发率的作用。掌握栓塞位置、栓塞剂用量和注射速度是防止并发症的关键。 相似文献
58.
59.
目的:制备脑干缺血动物模型并观察大鼠脑干缺血后早期组织学病理的超微结构。方法:应用两点电凝基底动脉的方法制作鼠脑干缺血动物模型。结果:病理学观察发现脑干缺血2小时即可出现超早期病理变化,并随时间的延长缺血性损害逐渐加重。结论:两点电凝基底动脉后可以造成稳定的脑干缺血,对急性脑干缺血的病理学研究有一定的价值。 相似文献
60.
Young-Mo Kim Sung-Jae Kim Jun-Young Yang Kyung-Cheon Kim 《Knee surgery, sports traumatology, arthroscopy》2007,15(7):847-850
We describe a firm, effective suture-tying method using a tensioner for reattaching tibial avulsion fractures of the anterior
cruciate ligament. Our simple method achieves strong, firm reattachment of the fracture. In addition, it prevents fixation
loosening during suture tying effectively. Since pullout repair using nonabsorbable sutures is commonly used to fix various
avulsion fractures, the tensioner helps attain strong, firm reattachment of avulsion fractures simply and effectively. 相似文献