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81.
肝移植术后血管并发症的病因学分析 总被引:3,自引:2,他引:1
目的 探讨肝移植术后血管并发症的病因。方法 对1993年4月~2002年4月所完成的160例原住肝移植临床资料进行回顾性分析。结果 肝动脉并发症发生率为5%,与肝动脉并发症相关的死亡率为3.13%;门静脉并发症发生率为3.75%,与门静脉并发症相关死亡率为0;肝后下腔静脉狭窄并发症发生率为3.75%。结论 肝移植术后早期魂脉并发症主要与手术技术和肝动脉病变有关,改进吻合技术,术前评估肝动脉病变能降低早期肝动脉并发症发生率;术前有门脉高压症手术治疗史、移植术前门静脉血栓、门静脉手术史以及严重感染病史等是门静脉并发症的高危因素;手术技术是导致下腔静脉狭窄的重要原因,腔静脉整形的改良背驮式肝移植能避免该并发症的发生。 相似文献
82.
养血清脑颗粒对慢性脑供血不足患者血管内皮功能的改善及血栓前状态的影响 总被引:7,自引:2,他引:5
目的探讨养血清脑颗粒对慢性脑供血不足患者血管内皮功能障碍和血栓前状态的干预效果。方法90例慢性脑供血不足患者按就时间顺序分为A组(对照组)、B组(养血清脑颗粒组)、C组(联合用药组)各30例,分别观察3组患者用药前和用药3个月后一氧化氮(NO)、血管内皮素-1(ET-1)、纤维蛋白原(FIB)、组织型纤溶酶原激活物抑制物(PAI-1)和组织型纤溶酶原激活物(t-PA)的变化,及内皮依赖性血管舒张功能(EDD)、非内皮依赖性血管舒张功能(NEDD)的变化,并进行对比分析。结果B组、C组经过治疗后,NO水平升高,ET-1水平和FIB减低,t-PA活性增强,PAI-1活性降低,EDD显著改善,两治疗组间相比差异无统计学意义;两治疗组治疗后分别与对照组相比差异具有统计学意义。结论服用养血清脑颗粒能够有效改善慢性脑供血不足患者的血管内皮依赖性舒张功能及血栓前状态,可以作为脑血栓形成的一级预防治疗。 相似文献
83.
目的:建立一种因血管内皮细胞损伤而诱导的大鼠局灶性脑梗死模型。方法:取S—D大鼠11只,分离左侧颈总动脉、颈外动脉和颈内动脉。结扎左颈外动脉远心端,夹闭左翼腭动脉和颈总动脉,经颈外动脉逆行插管并缓慢注入月桂酸钠至颈内动脉系统,造成大脑中动脉血管内皮细胞受损。结果:从模型动物的行为表现、梗死灶形态学和病理学进行考察,10只大鼠均产生一定程度的脑梗死表现,造模成功率为90.9%。结论:该模型的稳定性和重复性较好,能在大脑中动脉的供血区产生恒定的梗死灶,适合进行脑缺血损伤的有关实验研究。 相似文献
84.
目的研究加兰他敏对阿尔茨海默病(AD)大鼠认知功能的影响及NMDA受体在其中的作用。方法雄性SD大鼠65只,随机分为假手术、链脲菌素(STZ)组,加兰他敏、MK-801和犬尿烯酸3个治疗组。侧脑室注射STZ制备大鼠AD模型,水迷宫试验测定大鼠的学习记忆能力。3个治疗组分别给予加兰他敏、MK-801 加兰他敏、犬尿烯酸 加兰他敏,共6周。结果术后第10天各组潜伏期明显延长,过平台次数明显减少,差异均无统计学意义。治疗6周后加兰他敏组潜伏期缩短,过平台次数增加,与STZ组比较,有显著差异,而MK-801和犬尿烯酸组潜伏期和过平台次数与STZ组比较,无明显差异。结论加兰他敏对AD大鼠的认知功能具有明显的改善作用,而应用NMDA受体阻断剂后其治疗作用消失。说明NMDA受体介导了加兰他敏对AD大鼠认知功能的改善。 相似文献
85.
Association of Vascular Endothelial Growth Factor Expression with Tumor Angiogenesis and with Early Relapse in Primary Breast Cancer 总被引:10,自引:0,他引:10
Masakazu Toi Seigo Hoshina Toshiaki Takayanagi Takeshi Tominaga 《Cancer science》1994,85(10):1045-1049
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer. 相似文献
86.
Christopher Martin Stephen McKenzie David Ames 《International journal of geriatric psychiatry》1994,9(5):393-398
In order to determine whether a specialist psychogeriatric nursing home was fulfilling its intended role of caring for the most behaviourally disturbed dementia sufferers, 24 of its demented residents were compared with 28 demented individuals discharged from a psychiatric unit to ordinary nursing homes and 30 mobile dementia sufferers in nursing home wards of a geriatric centre. Those in the psychogeriatric nursing home showed more disturbed behaviours than those in the other two settings. Scores on the Rating Scale for Aggressive Behaviour in the Elderly were compared with degree of cognitive impairment for the first time in the literature and showed no correlation with degree of cognitive impairment for the first time in the literature and showed no correlation with congnitive performance. 相似文献
87.
The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression. 相似文献
88.
Declan Donovan BSc Dr. Judith H. Harmey PhD Deirdre Toomey BSc D. Henry Osborne MCh H. Paul Redmond MCh David J. Bouchier-Hayes MCh 《Annals of surgical oncology》1997,4(8):621-627
Background: Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic
factor identified to date. TGFβ-1 acts as an indirect angiogenic agent.
Methods: VEGF and TGFβ-1 were measured in the serum of breast cancer patients and agematched controls and in tumor tissue of cancer
patients by ELISA. VEGF protein and mRNA expression by breast tumor cell lines were examined, and the effect of TGFβ-1 on
VEGF production in these cells was assessed.
Results: VEGF levels were significantly higher (P=.03) in the serum of patients with breast cancer compared to age-matched controls. A positive correlation was found between
serum (r=0.539) and tumor tissue (r=0.688) levels of VEGF and TGFβ-1. Metastatic MDA-MB-231 breast cancer cells produce more
VEGF than do the primary BT474 cells. TGFβ-1 significantly (P<.05) increased production of VEGF.
Conclusions: Breast cancer cells constitutively produce VEGF protein and mRNA. There is a relationship between VEGF and TGFβ-1 levels
in breast cancer patients, and TGFβ-1 regulates VEGF expression by breast cancer cells.
Presented at the 50th Annual Cancer Symposium of the Society of Surgical Oncology, Chicago, Illinois, March 20–23, 1997. 相似文献
89.
90.
Tony Hope Kathleen M. Tilling Kathy Gedling Janet M. Keene Sandra D. Cooper Christopher G. Fairburn 《International journal of geriatric psychiatry》1994,9(2):149-155
‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories. 相似文献