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目的探讨同种异体骨髓基质细胞(MSCs)移植对SD大鼠缺血肢体治疗机制和规律,为MSCs移植治疗肢体缺血提供理论基础。方法体外全骨髓培养法培养雄性SD大鼠MSCs至三代。60只SD大鼠经结扎腹主动脉及双侧腹壁阴部动脉造成双下肢缺血模型,随机分为对照组(n=30)及移植组(n=30),造模后3天度过反应期后移植组右下肢腓肠肌及股二头肌内分5点注射移植含1×106个MSCs细胞悬液0.5ml,对照组同法注射生理盐水0.5ml。按移植后1周、2周、4周、6周、8周时两组再随机分为5个亚组(n=6),分别取动物麻醉后穿刺双侧髂静脉血行血氧分压测定,处死动物取左前肢,左后、右后肢骨骼肌标本4%多聚甲醛固定,制切片。行Y染色体性别决定区(SRY)原位杂交,血管内皮生长因子(VEGF)-mRNA原位杂交、HE染色,计数VEGF-mRNA阳性细胞数和毛细血管数。对照组仅作右后肢的相关检测。结果 SRY:移植组右后肢、左后肢、骨骼肌间间隙内有阳性细胞构成血管样结构,有的在血管周围,未见到呈阳性的骨骼肌细胞。左前肢的骨骼肌周围筋膜内偶尔可见到阳性细胞。对照组无阳性细胞发现。VEGF-mRNA原位杂交:对照组和移植组右后肢、左后肢VEGF-mRNA呈进行性升高(P0.001),而左前肢则无明显升高(P=0.694)。在第1周时对照组与移植组相比无统计学差异(P=0.079),随后移植组明显高于对照组(P0.001)。静脉血氧分压:对照组及移植组髂静脉血氧分压呈进行性升高(P0.001),移植组右后肢髂静脉氧分压较左后肢及对照组明显高(P0.05)。毛细血管计数:对照组及移植组右后肢、左后肢的毛细血管计数呈进行性增高(P0.05),而左前肢则无统计学意义(P=0.055),移植组中右后肢毛细血管计数明显高于左后肢及对照组(P0.05)。HE染色:未见明显组织细胞核异常分裂改变。结论移植的MSCs可以在同种异体动物体内长期生存、分化,促进缺血肢体的VEGF-mRNA的表达和毛细血管的成长。 相似文献
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目的建立2型糖尿病大鼠后肢缺血模型并进行评价,为后续的干预实验提供研究平台。方法将15只SD大鼠随机分为正常对照组、糖尿病组及糖尿病后肢缺血组,每组5只。糖尿病组及糖尿病后肢缺血组的10只大鼠均给予高脂饮食喂养4周后,腹腔注射链脲佐菌素(STZ,40mg/kg)以建立2型糖尿病模型。糖尿病后肢缺血组大鼠建模成功后行双侧髂总动脉结扎术以建立后肢缺血模型,正常对照组和糖尿病组大鼠仅分离髂总动脉,不予结扎。2周后对3组大鼠股动脉的起始段行彩色多普勒超声检查,以检测股动脉的血流峰值速度和血流加速时间;取缺血部位的小腿三头肌及大腿股四头肌组织,分别行HE染色及免疫组化SP染色,以观察3组大鼠肌细胞的营养状况及血管再生情况。结果后肢缺血模型建模2周后,正常对照组、糖尿病组和糖尿病后肢缺血组大鼠的血流峰值速度分别为(22.49±3.02)cm/s、(17.36±2.60)cm/s和(11.23±1.26)cm/s,血流加速时间分别为(0.080±0.009)S、(0.120±0.009)S和(0.160±0.020)s,糖尿病后肢缺血组大鼠的股动脉血流峰值速度小于正常对照组和糖尿病组(P〈0.05),而血流加速时间较长(P〈0.05)。HE染色结果显示:糖尿病后肢缺血组大鼠小腿三头肌的结构破坏,有大量炎症细胞浸润,肌肉损伤程度重于正常对照组和糖尿病组。免疫组化sP染色结果显示:糖尿病后肢缺血组大鼠大腿股四头肌的毛细血管密度[(1.40±0.55)个/HPF]小于正常对照组[(6.80±0.84)个/HPF]及糖尿病组[(4.60±0.55)个/HPF],差异均有统计学意义伊〈O.05)。结论对SD大鼠给予高脂饮食联合小剂量STZ注射可以成功诱导2型糖尿病模型,在此模型基础上结扎髂总动脉可以成功制备糖尿病后肢缺血模型。 相似文献
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目的观察采用两种不同方法建立的急性大鼠后肢动脉缺血动物模型的DSA表现。方法雌性SD大鼠60只,采用随机数字表分为A、B组,每组30只。A组结扎离断右侧股动脉,B组结扎离断右侧髂总动脉,建立急性大鼠后肢动脉缺血模型。结果术后4周,A组4只大鼠右侧股动脉远端完全未见显影,模型复制成功率14.81%(4/27);14只可见少量至中等量侧支循环建立;9只可见大量侧支循环建立和开放。B组3只大鼠右侧髂总动脉结扎离断远端血管未显影,模型复制成功率12.00%(3/25);10只可见少量侧支至中等量侧支循环建立;12只可见大量侧支循环建立和开放。两组大鼠模型复制成功率差异无统计学意义(P〉0.05)。结论使用DSA可清晰、准确地了解大鼠后肢动脉缺血模型循环建立开放的情况。结扎单侧股动脉及髂总动脉均可建立后肢动脉缺血大鼠模型。 相似文献
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大鼠移植动脉硬化加快模型的建立 总被引:1,自引:1,他引:0
目的 建立一种简捷 ,有代表性且稳定的移植物动脉硬化模型。方法 将SD大鼠的腹主动脉分别冷缺血 1、2 4、48h行SD→SD及SD→Wistar的原位腹主动脉移植 ,观察术后植入段血管病理改变、TGF β1表达及手术前后过氧化脂质的变化。结果 SD→SD及SD→Wistar缺血1h组分别于术后 10周及 6周见内膜明显增厚 ,而缺血 2 4h组只需 2周 ;各组移植后 2h过氧化脂质均明显高于术前 ,术后 4、2 4h与术前比差异无显著性 (P >0 .0 5 ) ;强化缺血组TGF β1不论是SD→SD还是SD→Wistar均于术后 1周即出现高表达。结论 以SD/Wistar作为供 /受体行腹主动脉移植 ,强化冷缺血损伤 ,可加快移植物动脉硬化 ,可望成为新型慢排模型。 相似文献
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缺血预处理对脊髓缺血损伤细胞内Ca2+变化的影响 总被引:1,自引:1,他引:0
目的 观察缺血预处理对脊髓缺血损伤细胞内 Ca2 变化的影响。 方法 将 44只健康新西兰大白兔随机分为三组 :缺血组 2 0只 ,缺血预处理组 2 0只 ,假手术组 4只。缺血组于左肾动脉下夹闭腹主动脉 40分钟后开放灌注 ;缺血预处理组夹闭腹主动脉 5分钟 ,开放 15分钟 ,再次夹闭 40分钟后开放再灌注 ;假手术组动物手术操作同缺血组 ,但不夹闭腹主动脉。分别于夹闭 40分钟后即刻、开放再灌注 2小时、8小时、2 4小时和 72小时各时相点测定脊髓组织 Ca2 含量 ,并评定、记录动物后肢神经功能。 结果 缺血预处理组脊髓组织 Ca2 显著低于缺血组各时相值 ;再灌注 8小时后神经功能评分缺血预处理组明显高于缺血组 (P<0 .0 1)。 结论 缺血预处理具有降低神经元胞浆游离 Ca2 浓度 ,防止Ca2 超载 ,稳定细胞内环境的能力 ,对主动脉阻断所致的脊髓缺血损伤有良好的保护作用。其表现为明显降低瘫痪发生率 ,增加术后神经评分 相似文献
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Baclofen对慢性神经痛大鼠镇痛效果的影响 总被引:2,自引:0,他引:2
目的 研究GABAB 受体激动剂baclofen对慢性神经痛大鼠痛阈的影响以及对脊髓c fos表达的影响 ,探讨脊髓GABA能系统在神经痛调节中的可能机制。方法 结扎大鼠左侧L5脊神经根建立慢性神经痛模型。SD大鼠 2 4只随机等分成 (1)假手术 +baclofen组 :大鼠背部假手术而未行神经根结扎 ,术后 2 8至 34d每天腹腔注射baclofen 10mg/kg两次 ;(2 )假手术组 :背部假手术后2 8至 34d每天腹腔注射 0 9%NaCl 2ml两次 ;(3)L5结扎 +baclofen组 :实施L5神经根结扎 ,术后2 8至 34d每天腹腔注射baclofen 10mg/kg两次 ;(4)L5结扎组 :实施L5神经根结扎 ,术后 2 8至 34d每天腹腔注射 0 9%NaCl 2ml两次。术后 1、3、7、10、14、2 1、2 8、35d测大鼠双后肢光热刺激性痛阈。术后 35d处死大鼠取出腰段脊髓 ,冰冻切片 ,免疫组化法检测c fos免疫阳性细胞。结果 (1)术后 7~ 2 8d ,左L5脊神经结扎大鼠较假手术大鼠痛阈明显降低 (P <0 0 1)。术后 35d ,使用与不使用baclofen大鼠的假手术大鼠左后肢痛阈无显著变化 (P >0 0 5 ) ,双侧脊髓深层 (Ⅲ Ⅹ层 )FLI细胞无显著差异 (P >0 0 5 ) ;(2 )术后 35d ,使用baclofen的L5结扎大鼠的左后肢痛觉显著低于未使用baclofen的L5结扎大鼠 (P <0 0 1) ,前者脊髓深层 (Ⅲ Ⅹ层 )FLI细胞显著 相似文献
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大鼠小肠移植血管吻合术式的改进 总被引:3,自引:0,他引:3
大鼠小肠移植是一项难度较大的实验外科技术,血管吻合是影响其成功的关键。现报道一种简便易行的大鼠小肠移植血管吻合改良术式。一、材料与方法1.供体手术:结扎双侧肾动脉、腹腔干及腰动脉分支,游离带肠系膜上动脉的一段腹主动脉。离断全小肠远近端。分离门静脉周围的胰腺组织,结扎其分支。用0.2%丁胺卡那霉素5ml灌洗肠腔。结扎已分离的腹主动脉段的近心侧,于远心侧向心插管,以40ml/小时速度向腹主动脉灌注4℃含25u/ml肝素的乳酸林格氏液,于肝门处离断门静脉,至小肠移植物苍白后迅速取下。4℃条件下修整移植肠腹主动脉段,将门静… 相似文献
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贾英斌|李坚|潘海燕|苏永辉|关晓东|张百萌 《中国普通外科杂志》2011,20(12):1347-1350
目的建立大鼠慢性后肢缺血模型并与其急性后肢缺血模型比较,分析两者术后血流灌注和基因表达的差异。方法 40只SD大鼠随机均分为2组,分别建立大鼠慢性(结扎、离断右侧髂股动脉分支,股动脉内置入抗凝硅胶管并固定)和急性后肢缺血模型(结扎、离断右侧髂股动脉分支后直接结扎并切除股动脉)。用激光多普勒血流检测仪记录术前至术后连续4周肢体血流灌注情况。用实时荧光定量PCR法检测术后24 h患肢股内收肌缺氧诱导因子1α(HIF-1α)和血管内皮生长因子(VEGF)基因的表达。结果术后24 h,急性缺血组患肢股内收肌HIF-1α和VEGF表达水平均明显高于慢性缺血组(均P<0.05)。急性缺血组血流灌注在术后即刻降至对侧肢体的24%,但恢复较迅速,至术后28 d达到并稳定在82%;慢性缺血组于术后7 d达到血流灌注谷值(48%),随后缓慢恢复,至术后28 d至最高值(67%)。两组血流灌注水平在各观察时间点均有统计学差异(均P<0.05)。结论大鼠慢性和急性后肢缺血模型的病变特点及基因表达存在差异,慢性后肢缺血模型更符合临床严重肢体缺血的病理过程。 相似文献
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一种大鼠门静脉高压脾功能亢进模型的建立 总被引:1,自引:0,他引:1
目的通过门静脉缩窄联合脾静脉结扎的方法,建立大鼠门静脉高压脾功能亢进模型。方法 60只健康雄性SD大鼠按随机数字表法分为假手术组(n=20)、门静脉缩窄组(缩窄组,n=20)和门静脉缩窄联合脾静脉结扎组(联合组,n=20),其中假手术组仅予以开、关腹术,缩窄组予以单纯门静脉主干缩窄术,联合组予以门静脉缩窄联合脾静脉结扎术。造模开始前和造模后7周每周采各组动物外周血行红细胞、白细胞及血小板计数动态观察;于造模开始前和造模后第7周测量各组动物门静脉压力及脾横、长径,于造模后第7周处死动物后计算各组脾指数并观察脾脏组织的病理学变化。结果联合组大鼠外周血血小板及红细胞计数于第3周起明显低于假手术组及缩窄组(P<0.05);而3组白细胞计数各时相间差异均无统计学意义(P>0.05)。第7周时缩窄组及联合组门静脉压力均较术前明显升高(P<0.05),并且明显高于假手术组(P<0.05)。第7周时联合组的脾横径及脾长径较术前明显增大(P<0.05),并且明显大于假手术组及缩窄组(P<0.05),其脾指数亦高于假手术组及缩窄组(P<0.05)。第7周时联合组脾脏有典型的脾功能亢进的病理改变,而另2组未见明显病理改变。结论通过门静脉缩窄联合脾静脉结扎的方法,成功建立了大鼠继发性门静脉高压脾功能亢进模型,该方法手术操作简便、效果稳定,具有良好的科研应用价值。 相似文献
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Abdominal wall endometriomas 总被引:19,自引:0,他引:19
Blanco RG Parithivel VS Shah AK Gumbs MA Schein M Gerst PH 《American journal of surgery》2003,185(6):596-598
BACKGROUND: The diagnosis of abdominal wall endometriomas is often confused with other surgical conditions. METHODS: A retrospective study was made of 12 patients presenting with an abdominal wall mass, which proved to be endometrioma. RESULTS: Of a total of 297 patients of endometriosis treated in our hospital over a 7-year period, 12 (4%) had isolated abdominal wall endometriomas. Their mean age was 29.4 years. The presenting symptoms were abdominal mass (n = 12), cyclical (n = 5) or noncyclic pain (n = 7), dyspareunia and dysmenorrhea (n = 1). All patients had a history of gynecologic operations and presented, after an average of 1.9 years, with a tender mass (average 4 cm) at the previous incision site. Preoperative diagnosis was correct in 4 patients (33%) who presented with a cyclically painful abdominal mass. The others were diagnosed as incisional hernia (n = 4), "abdominal wall tumor" (n = 2), and inguinal hernia (n = 2). All patients underwent wide excision of their endometrioma; 2 required polytetrafluoroethylene patch grafting for the resulting fascial defect. The diagnosis was confirmed at frozen section or conventional histological examination in all patients. At follow-up, ranging from 4 months to 3 years, there was no recurrence of endometrioma. CONCLUSIONS: Scar endometrioma commonly presents as an abdominal mass with noncyclical symptoms. Imaging techniques are nonspecific and needle biopsy may confirm the diagnosis. Wide excision is the treatment of choice for abdominal wall endometrioma as well as for recurrent lesions. 相似文献
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J. J. Wever J. D. Blankensteijn I A. M. J. Broeders B. C. Eikelboom 《European journal of vascular and endovascular surgery》1999,18(6):481-486
BACKGROUND: successful endovascular repair of abdominal aortic aneurysms (AAA) generally leads to a decrease in aneurysm size. Theoretically, this may lead to foreshortening of the excluded segment. If so, vertically rigid endografts may dislocate over time and cover renal or hypogastric arteries. AIM: to assess length changes of the infrarenal aorta after endovascular AAA exclusion. PATIENTS AND METHODS: forty-four consecutive patients were scheduled for the EndoVascular Technologies endograft, a vertically non-rigid prosthesis which would potentially accommodate longitudinal changes. Twenty-four patients had completed at least 6 months of follow-up. In 18/24 patients a decrease in size was established by aneurysm volume measurements at 6 months' follow-up. Helical computer tomography (CT) angiograms were processed on a workstation. Aortic lengths were measured along the central lumen line from the lower renal artery orifice to the native aortic bifurcation. The computer tomography angiogram (CTA) reconstruction thickness of 2 mm yields at least a 4-mm error for each length measurement. RESULTS: in the shrinking aneurysm group, the median length change was 0 mm (range -9 mm to +4 mm) at 6 months' follow-up (n =18) and also 0 mm (range -7 mm to +4 mm) at 12 months' follow-up ( n =10). In 16/18 patients, length changes remained within the measurement error range of 4 mm. CONCLUSION: in this group of shrinking aneurysms after endovascular AAA repair, foreshortening of the excluded aortic segment appears not to be a clinically significant problem. 相似文献
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R Parravicini S Verona G Aguggini C Muneretto A Zarcone C Granot 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》1986,18(1):65-68
This study describes a new kind of abdominal heart transplantation for left ventricular assistance carried out in a series of 12 experiments in pigs weighing 15-25 kg. This was achieved making three connections between the donor's left atrium, aorta and pulmonary artery with the recipient's aorta, still aorta and inferior vena cava, respectively. The hemodynamic data were satisfactory, the best survival rate with a transplanted working heart was 1 month. The low output of the recipient's left ventricle was obtained by ligation of the left anterior descending (LAD) coronary artery. In all animals, the highest peak of the pressure of the transplanted left ventricle was at least 20 mm Hg higher (ranging from 20 to 60 mm Hg) than the pressure in the recipient's left ventricle, and corresponded with the peak of the systemic arterial pressure. The cardiac output of the transplanted hearts showed a good hemodynamic response with support of the circulation after ligation of the LAD coronary artery in the recipient's heart. 相似文献
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Patency of vascular prostheses implanted in the rat aorta is usually confirmed by reoperation and inspection of the distal stump of the aorta for pulsations. Repeated reoperation on rats included in long-term investigations is not possible because of the increasing formation of scar tissue and adhesions at the site of the distal aorta. Consequently, noninvasive ultrasonic Doppler measurement was investigated to determine whether this method could provide accurate information about the patency of an implanted prosthesis. A total of 37 rats with 10-cm-long prostheses implanted in the aorta (groups C nonsupported prostheses, n = 12; and D supported prostheses, n = 25), eight normal nonoperated controls (group A), and three rats with a ligated aorta (negative controls, group B) were studied over a period of 12 weeks. The Dopplerrecordings obtained in the normal animals served as controls for the recordings of rats with an implanted prosthesis. A prosthesis was considered patent if the Dopplermeasurements obtained from the femoral artery resembled that of the normal pattern. In seven cases a prosthesis was suspected to be occluded since the Dopplermeasurements resembled those obtained after aortic ligation. Autopsy confirmed the Dopplermeasurements in all cases. No Dopplermeasurements returned to normal in the femoral artery in the aorta-ligated rats even after longer periods post-operation. It is concluded that Dopplermeasurements can accurately provide information about the patency of a vascular prosthesis implanted in the rat aorta. 相似文献
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目的探讨球囊阻断低位腹主动脉控制腰骶骨肿瘤切除手术出血的效果。方法2008年6月~2009年9月11例腰骶骨肿瘤切除术中应用球囊导管阻断低位腹主动脉(球囊组),并与2006年10月~2008年5月21例(对照组)应用传统方法切除腰骶骨肿瘤进行比较,比较术中出血量。结果球囊组术中出血量(1223±348)ml,术中阻断腹主动脉1~3次,出血多在解除阻断间隙和肿瘤切除术后。对照组术中出血量(3519±978)ml,其中6例循环波动较大,需要血管活性药物维持。2组出血量差异有显著性(t=7.491,P=0.000)。结论腰骶骨肿瘤切除手术中应用球囊阻断低位腹主动脉能够有效减少出血量,利于肿瘤切除,是一项具有临床实用价值的微创技术。 相似文献
17.
Two patients developed abdominal aortic aneurysm rupture following bilateral iliac artery ligation and axillobifemoral bypass. The first patient developed his rupture several weeks after outflow ligation and apparent thrombosis of the aneurysm. At autopsy, the aneurysmal rupture occurred in the left posterior junction between the thrombosed aneurysm and the normal aorta. In the second case, the aneurysm was not completely thrombosed and plans were in progress for thrombosis of the aneurysm when the patient developed frank rupture, necessitating operative intervention. The authors await the published experience of others with bilateral common iliac artery ligation and extra-anatomic bypass for abdominal aortic aneurysm, but these authors do not currently recommend this management plan. 相似文献
18.
Mehmet Salih Aydin Aydemir Kocarslan Sezen Kocarslan Ahmet Kucuk ?rfan Eser Hatice Sezen Evren Buyukfirat Abdussemet Hazar 《Brazilian Journal Of Cardiovascular Surgery》2015,30(1):77-83
Introduction
Previous studies have demonstrated that thymoquinone has protective effects against ischemia reperfusion injury to various organs like lungs, kidneys and liver in different experimental models.Objective
We aimed to determine whether thymoquinone has favorable effects on lung, renal, heart tissues and oxidative stress in abdominal aorta ischemia-reperfusion injury.Methods
Thirty rats were divided into three groups as sham (n=10), control (n=10) and thymoquinone (TQ) treatment group (n=10). Control and TQ-treatment groups underwent abdominal aorta ischemia for 45 minutes followed by a 120-min period of reperfusion. In the TQ-treatment group, thymoquinone was given 5 minutes. before reperfusion at a dose of 20 mg/kg via an intraperitoneal route. Total antioxidant capacity, total oxidative status (TOS), and oxidative stress index (OSI) in blood serum were measured and lung, kidney, and heart tissue histopathology were evaluated with light microscopy.Results
Total oxidative status and oxidative stress index activity in blood samples were statistically higher in the control group compared to the sham and TQ-treatment groups (P<0.001 for TOS and OSI). Control group injury scores were statistically higher compared to sham and TQ-treatment groups (P<0.001 for all comparisons).Conclusion
Thymoquinone administered intraperitoneally was effective in reducing oxidative stress and histopathologic injury in an acute abdominal aorta ischemia-reperfusion rat model. 相似文献19.
腹腔区域性血流阻断动脉内介入化疗对循环系统影响的实验研究 总被引:2,自引:1,他引:1
目的:研究腹腔区域性血流阻断动脉内介入化疗对机体循环系统的影响。对象与方法:16头幼猪分为两组,每组8头,分别行腹腔区域性血流阻断(Stop-flow,SF)及区域性血流阻断动脉内介入化疗(Stop-flow-Chemotherapy,SFC,MMC 0.2mg/kg)。术中监测心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、肺动脉压(PAWP)、心排量(CO)、外周静脉阻力(SVR)及混合血氧饱和度(SvO2)。结果:两组实验动物术中的血流动力学指标均有较明显改变。血流阻断及再通后心率、心排量、血压、外周静脉阻力和混合静脉血氧饱和度(SvO2) 有显著变化,阻断开放后PAWP有一过性升高,CVP术中无明显改变,血流再通20分钟左右上述指标均基本恢复至术前水平。SF与SFC两组间无明显差异。结论:腹腔区域性血流阻断动脉内介入化疗对循环系统有一定影响,但均在可控制范围,提示在临床应用是安全可靠的。 相似文献
20.
目的比较不缝合皮下脂肪层的关腹方式与传统关腹方式的切口愈合效果。方法选取2010年9月至2012年9月期间笔者所在医院科室收治的患者400例,随机分为2组:观察组199例,采用不缝合皮下脂肪层的缝合方式;对照组201例,采用传统的分层缝合方式。比较2组患者的切口愈合效果。结果观察组发生脂肪液化1例(0.5%)、切口红肿3例(1.5%)、切口硬结1例(0.5%)、切口裂开0例及皮下血肿2例(1.0%),对照组上述并发症的发生数量分别为18例(9.0%)、16例(8.0%)、15例(7.5%)、9例(4.5%)及0例,除皮下血肿发生率的差异无统计学意义(P〉0.05)外,观察组其余切口并发症的发生率均低于对照组(P〈0.01)。观察组切口全部一期愈合(100%),对照组愈合186例(92.5%),观察组的-期愈合率较高泸〈0.01)。观察组的关腹时间和术后住院时间分别为(13.0±1.6)min和(7.7±1.3)d,均短于对照组[(18.0±2.2)min,(9.6±1.9)d,P〈0.01]。结论不缝合皮下脂肪层的切口缝合方式的切口愈合效果明显优于传统的分层缝合方式,值得推广。 相似文献