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71.
72.
活血化瘀中药联合血管内皮生长因子基因转移促进股骨头坏死处新生血管形成的实验研究 总被引:5,自引:4,他引:1
目的:观察活血化瘀中药联合血管内皮生长因子(VEGF)基因转移对促进股骨头缺血坏死处新生血管形成情况。方法:日本大耳兔40只,随机分为对照组、模型组、中药组、基因组和综合组。治疗8周后采用免疫组织化学方法观察股骨头滑膜VEGF阳性细胞率及数字减影血管造影股骨头血管数目改变情况。结果:模型组VEGF阳性细胞表达率减低,与对照组、基因组、综合组比较,差异有显著性意义(P<0.01),与中药组比较,有统计学差异(P<0.05),综合组VEGF阳性细胞表达率较高,与中药组及基因组比较,有统计学差异(P<0.05)。血管数目:在A区,各组与模型组比较,均无统计学差异;在B区,各组较模型组血管数目均有增加,对照组、基因组、综合组与模型组比较,有统计学差异(P<0.05)。综合组与基因组比较有统计学差异(P<0.05),中药组虽然血管数目较模型组多,但是无统计学意义。结论:活血化瘀中药及VEGF基因转移均可促进股骨头缺血坏死处局部新生血管形成和侧支循环的建立,尤以活血化瘀中药联合基因疗法效果为好,为临床应用活血化瘀中药联合基因疗法治疗股骨头缺血性坏死提供实验依据。 相似文献
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74.
OBJECTIVE: Tumours of the upper rectum, and many in the middle third, are not accessible to endorectal ultrasound staging because of the difficulty in reaching all sites of the rectum with a rigid probe. The aim of this prospective study was to assess whether using a dedicated rectosigmoidoscope, endorectal ultrasonography (ERUS) can accurately stage any rectal lesion irrespective of its distance from the anal verge. METHOD: A total of 173 consecutive patients with a primary rectal tumour were included. A rotating, high multifrequency (5.0-10 MHz) endoprobe was introduced through a dedicated rectosigmoidoscope and advanced above the lesion. A computer allowed for three-dimensional (3D) reconstruction of 2D images. Treatment was selected on the basis of 3D-ERUS findings. ERUS staging was correlated with pathological staging. RESULTS: The depth of invasion was correctly determined by 3D-ERUS in 78.2% of tumours of the lower rectum, 76.4% of tumours extending between the lower and middle third of the rectum, 80.9% of tumours of the middle third of the rectum, 78.5% of tumours extending between the middle and upper third of the rectum and 78.9% of tumours of the upper rectum. The accuracy for the absence of lymph node metastases was 81.2% for tumours of the lower rectum, 78.5% for tumours extending between the lower and middle third of the rectum, 85.7% for tumours of the middle third of the rectum, 83.3% for tumours extending between the middle and upper third of the rectum and 78.5% for tumours of the upper rectum. Analysis showed that there was no difference between the various tumour sites. CONCLUSION: Our findings indicate that using a dedicated proctosigmoidoscope, tumours of the upper and middle third of the rectum are equally accessible to ultrasonographic evaluation. The distance of the tumour from the anal verge does not influence the accuracy of examinations considered adequate by the operator. 相似文献
75.
Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
76.
目的:探讨休克后促炎细胞因子的表达、释放时相及伴随的肠、肝、肺组织病理变化。方法:80只SD大鼠随机均分为失血性休克组和对照组。采用RT-PCR、ELISA方法检测失血性休克后30、60、90min及复苏后30、90min肠、肝、肺组织内TNF-α、IL-6 mRNA表达及血清中TNF-α、IL-6含量;HE和IHC染色检测伴随的组织病理变化。结果:①休克30min时,肠、肝、肺内的促炎细胞因子表达未见升高;60min时肠道先出现TNF-αmRNA表达升高(P〈0.05):而肝脏在90min开始表达升高(P〈0.05),肺脏则在复苏后30min开始表达升高(P〈0.05)。复苏后90min肠、肝、肺的细胞因子表达都继续显著升高(P〈0.01)。②TNF-α 在肠、肝、肺的表达升高最早,其后为IL-6 mRNA。③30min时门静脉和外周血中TNF-α、IM的含量与对照组相比无显著差异,而60min时门静脉血中含量显著升高(P〈0.01)。④休克后肠黏膜坏死脱落;肝组织结构紊乱、肝窦增宽、肝细胞变性坏死;肺脏间质水肿、炎症细胞浸润。结论:失血性休克时细胞因子的释放顺序是肠道、肝脏和肺脏,推测存在“肠-肝-肺”细胞因子释放轴的可能,有待进一步确定。 相似文献
77.
A. Mäkipernaa O. Koskimies J. Jääskeläinen A. -M. Teppo M. A. Siimes 《European journal of pediatrics》1991,150(6):444-447
In order to obtain more information on the long-term effects of treatment of Wilm's tumour we investigated 30 subjects treated at the Children's Hospital between 1960 and 1976. All had been nephrectomized and in 4 the length of the remaining kidney was subnormal. In the other subjects kidney length was related to follow up time and age at follow up. Blood pressure was elevated in 5 subjects. Urinary albumin excretion deviated only slightly from normal. Tubular functions were well preserved in all subjects. In this small series we were unable to establish any relation between the abnormalities observed and the treatment given. Our results suggest that, despite wide interindividual variation those who survive Wilm's tumours seldom have long-term renal complications. 相似文献
78.
79.
杀菌性通透性增强蛋白对失血性休克的保护作用及其机理 总被引:2,自引:0,他引:2
分别在失血和复苏开始即刻iv杀菌性/通透性增强蛋白(BPI)1.5和3.5mgkg-1,观察BPI对大鼠失血性休克转归的影响.结果显示,BPI治疗能明显改善失血性休克大鼠肝肾功能,提高休克动物存活率(BPI组81%vs休克对照组44%,P<0.05),BPI组大鼠复苏后与休克前的血浆内毒素(0.20±0.04vs0.24±0.05kUL-1)水平无明显变化,血浆肿瘤坏死因子α和白介素6水平较休克前明显升高,但均显著低于休克对照组.提示BPI对失血性休克大鼠具有一定的保护作用,其机理可能与BPI拮抗休克时内源性内毒素活性,抑制细胞因子反应有关. 相似文献
80.
Carol A. Sawka Kathleen I. Pritchard Wendy Shelley Gerrit DeBoer Alexander H.G. Paterson J. William Meakin Donald J.A. Sutherland 《Breast cancer research and treatment》1997,43(3):211-215
Background: The outcome of breast cancer is usuallydetermined by multiple factors. Serum tumor necrosis factoralpha concentration has been found to be increasedin the circulation of patients with malignancy. Thisstudy was designed with the aim to investigateany correlation between the serum tumor necrosis factoralpha and the clinicopathological fetures and furthermore evaluatethe prognostic significance of serum tumor necrosis factoralpha concentration in breast cancer. Methods: Forty consecutivepatients with invasive breast cancer undergoing modified radicalmastectomy were prospectively included and evaluated. Venous bloodsamples were collected before the surgery. Sera wereobtained by centrifugation, and stored at – 70°C until assayed. The control group consisted 30healthy, age-matched subjects. Serum concentrations of tumor necrosisfactor alpha were measured by the quantitative sandwichenzyme immunoassay technique. The data on tumor size,age, estrogen receptor status, lymph node status andTNM staging were reviewed and recorded.Results: The mean value of serum tumor necrosis factor alphain patients with invasive breast cancer was 1.47± 0.58 pg/ml and that of the controlgroup was 0.98 ± 0.37 pg/ml, and thedifference was significant (P < 0.01). With univariableanalysis, patients with maximum tumor size of 5cm or larger (P=0.03), more advancedTNM staging (P < 0.01); and more advancedlymph node status (P < 0.01) were shownto have significantly higher serum concentrations of tumornecrosis factor alpha. However, with multivariable analysis, TNMstaging appeared as the only independent factor (P< 0.01) predicting the significant, higher serum concentrationsof tumor necrosis factor alpha. Conclusion: Preoperative evaluationof serum tumor necrosis factor alpha concentrations maybe a valuable parameter for reflecting the severityof staging for invasive breast cancer. 相似文献