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951.
目的研究三氧化二砷在体外对人骨肉瘤细胞(U2-OS)形态及细胞凋亡的影响。方法以不同浓度三氧化二砷(0.5、1.0、1.5μmol/L)作用骨肉瘤细胞,15 mg/L 5-FU作为阳性对照,采用荧光显微镜观察细胞核形态及流式细胞仪检测细胞凋亡率。结果各浓度的三氧化二砷对骨肉瘤细胞(U2-OS)的形态均有影响,随着三氧化二砷浓度的升高,细胞核发生固缩越明显,细胞凋亡率越高,与正常对照组相比,差异具统计学意义。结论三氧化二砷可导致骨肉瘤细胞(U2-OS)细胞核发生固缩坏死和凋亡,凋亡率与三氧化二砷浓度有依赖关系,在一定浓度范围内随浓度增高而增高。 相似文献
952.
Zhao WC Yang N Zhu N Zhang HB Fu Y Zhou HB Cai WK Chen BD Yang GS 《World journal of surgery》2012,36(8):1811-1823
Background
Surgical strategies for the treatment of multiple hepatocellular carcinomas (HCC) remain controversial. This study compared the prognostic power of the University of California, San Francisco (UCSF) criteria with the Barcelona Clinic Liver Cancer (BCLC) early-stage criteria.Methods
Clinical and survival data of 162 multiple-HCC patients in Child-Pugh class A who underwent curative resection were retrospectively reviewed. Prognostic risk factors were analyzed using univariate and multivariate analyses.Results
UCSF criteria were shown to independently predict overall and disease-free survival. In patients within the UCSF criteria, 3-year overall and disease-free survivals were significantly better than in those exceeding the UCSF criteria (68 vs. 34?% and 54 vs. 26?%, respectively; both p?0.001). There were no significant differences in 3-year overall and disease-free survival between patients within the UCSF criteria but exceeding the BCLC early stage and patients with BCLC early-stage disease (71 vs. 66?%, p?=?0.506 and 57 vs. 50?%, p?=?0.666, respectively). Tumors within the UCSF criteria were associated with a lower incidence of high-grade tumor (p?=?0.009), microvascular invasion (p?=?0.005), 3-month death (p?=?0.046), prolonged Pringle’s maneuver (p?=?0.005), and surgical margin <0.5?cm (p?0.001) than those exceeding the UCSF criteria. Tumors within the UCSF criteria but exceeding the BCLC early stage had invasiveness and surgical difficulty similar to those within the BCLC early-stage criteria.Conclusions
Multiple HCC patients within the UCSF criteria benefit from curative resection. Expansion of curative treatment is justified. 相似文献953.
PurposeWe performed a meta-analysis of Phase III randomized trials to compare treatment outcomes for early-stage breast cancer patients receiving adjuvant chemotherapy with sequential or concurrent anthracyclines and taxanes.MethodsAll Phase III randomized trials comparing adjuvant chemotherapy of sequential or concurrent anthracyclines and taxanes in early-stage breast cancer patients were considered eligible. A total of three trials that enrolled 8728 women were analyzed. A pooled analysis was accomplished and event-based risk ratios (RR) with 95% confidence intervals (95%CI) were derived. The significant differences in disease-free survival (DFS) and overall survival (OS) were explored. A heterogeneity test was applied as well.ResultsAmong three eligible trials, significant differences in favor of sequential regimen were seen in DFS (RR: 0.90; 95%CI: 0.84 to 0.98; P = 0.01) and in OS (RR: 0.88; 95%CI: 0.79 to 0.98; P = 0.02).ConclusionConsidering all the available Phase III trials, sequential adjuvant chemotherapy for early breast cancer seems to add a significant benefit in both DFS and OS over concurrent regimens. 相似文献
954.
Li Y Zhu W Zuo L Zhang W Gong J Gu L Cao L Li N Li J 《Journal of gastrointestinal surgery》2012,16(8):1539-1547
Background
Data on risk factors of postoperative recurrence in patients with Crohn??s disease (CD) have shown conflicting results. The aim of this retrospective study is to identify predictors of early symptomatic recurrence of CD after surgical intestinal resection in the Chinese population.Materials and Methods
Patients diagnosed as CD who underwent intestinal resection in Jinling Hospital between May 2004 and December 2010 were included in our study. Clinical data of these patients were reviewed. Multivariable survival analysis was performed to elucidate risk factors of early postoperative symptomatic recurrence.Results
There were a total of 141 CD patients who had at least one previous curative resection for CD under regular follow-up in our unit. Our data indicated disease behavior (95?% CI 1.01?C1.70, P?=?0.044), smoking habits (95?% CI 1.32?C2.84, P?=?0.001), indication of perforation (95?% CI 1.09?C4.02, P?=?0.026), and location of anastomosis (95?% CI 1.09?C3.39, P?=?0.023) which are, as a result, strong independent predictors of symptomatic recurrence, while the anastomosis type as side-to-side anastomosis (SSA) was significantly associated with a decreased risk of symptomatic recurrence when compared with other anastomosis type (95?% CI 0.26?C0.94, P?=?0.038). Medical prophylaxes also played a role in the prevention of postoperative symptomatic recurrence.Conclusions
A smoking habits and perforation indication for surgery at the time of resection are associated with an increased risk of symptomatic recurrence. Anastomosis type with SSA is associated with a reduced risk of symptomatic recurrence. This population-based study supports the concept that environmental factors, disease character, and surgical technique influence the risk of postoperative symptomatic recurrence of CD. 相似文献955.
The feasibility of porcine small intestinal submucosa (SIS) as a carrier in skin flap prefabrication was examined in this study. Thirty-eight rats were randomly divided into five groups. The saphenous vascular bundle was used as the vascular carrier. In group 1 (n = 8), an arteriovenous fistula was made by anastomosis of distal saphenous artery and vein. A SIS patch (1.5 x 2 cm2) was placed underneath the vascular bundle. In group 2 (n = 8), the vascular bundle was isolated and laid over the SIS patch. The distal saphenous vessels were ligated when the flap was raised. In group 3 (n = 8), an arteriovenous fistula was made without SIS implant. In group 4 (n = 8), the flap was raised with only the vascular bundle with the distal end ligated. After 2 weeks of maturation, the flap was raised with only the vascular bundle. In group 5 (n = 6), SIS was implanted and the flap including the SIS patch was raised and replaced without the vascular pedicles. The survival of the flaps and histology were evaluated at 5 days after flap replacement. The results showed that the average survival area in group 1 was 99% +/- 3% and the survival area in group 2 was 86% +/- 16%. The mean survival areas in group 3 and 4 were 60% +/- 9% and 25% +/- 10%, respectively. No flap survival was observed in the group 5. These were significantly lower than in groups 1 and 2 (p < 0.05, p < 0.01). Histology showed that SIS patch was incorporated into the adjacent connective tissue and increased amounts of neovascularization were seen between the collagenous sheets and dermis. In conclusion, this study demonstrated that porcine SIS can incorporate into the adjacent tissue and induce angiogenesis in flap prefabrication. This biomaterial can provide a scaffold for supporting and enhancing the survival of vascular prefabricated skin flap. 相似文献
956.
BACKGROUND: We examined the effect of 11,12-epoxyeicosatrienoic acid (EET(11,12)) added to St. Thomas' Hospital (ST) solution or University of Wisconsin (UW) solution on endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation under clinically relevant temperature and exposure time. METHODS: Porcine coronary microarteries (200 to 450 microm) were incubated with Krebs' solution (control), ST with or without EET(11,12) (300 nmol/L) at 22 degrees C for 1 hour as well as at 4 degrees C for 1 or 4 hours, and UW with or without EET(11,12) at 4 degrees C for 4 hours. The EDHF-mediated relaxation was induced by bradykinin (-10 to approximately -6.5 log M) in the precontraction evoked by U(46619) (10 nmol/L) or U(46619) (1 nmol/L) plus endothelin-1 (6 nmol/L). RESULTS: The EDHF-mediated relaxation was reduced after exposure to UW (79.7% +/- 4.6% versus 93.6% +/- 2.8%, p = 0.01) at 4 degrees C for 4 hours. One-hour exposure to ST under 22 degrees C or 4 degrees C decreased the relaxation (75.2% +/- 7.6% versus 96.7% +/- 1.6%, p < 0.05) or the sensitivity to bradykinin (-8.04 +/- 0.15 versus -8.50 +/- 0.20 log M, p < 0.05). The relaxation increased to 86.8% +/- 5.3% by addition of EET(11,12) to ST (1 hour at 22 degrees C, p < 0.05) but was unchanged when added to either ST or UW at 4 degrees C for 1 or 4 hours. CONCLUSIONS: As an additive to ST solution, EET(11,12) may partially restore EDHF-mediated endothelial function under moderate hypothermia but had no significant effect under profound hypothermia when added to either ST or UW solution. Further investigation is necessary to improve the effect. 相似文献
957.
Ruel MA Sellke FW Bianchi C Khan TA Faro R Zhang JP Cohn WE 《The Annals of thoracic surgery》2003,75(5):1443-1449
BACKGROUND: The gastrointestinal submucosa physiologically produces angiogenic proteins. We examined whether these properties could lead to endogenous myocardial angiogenesis in a swine model of chronic ischemia. METHODS: Fifteen Yorkshire swine underwent ameroid constrictor placement around the circumflex artery and either lateral epicardial abrasion, creation of a gastroepiploic artery (GEA) based gastric patch, mucosal avulsion, transdiaphragmatic transfer, and apposition of the patch against the circumflex myocardial territory (number = 8; test animals), or lateral epicardial abrasion alone (number = 7; controls). Seven weeks later, lateral myocardial perfusion, endothelial cell density, and expression of VEGFR-1 and VE-cadherin were determined using isotope-labeled microsphere assays, immunohistochemistry, and immunoblotting, respectively. RESULTS: Microsphere assays showed equivalent lateral/anterior myocardial perfusion indices at rest (1.10 +/- 0.49 vs 0.95 +/- 0.23, test vs control animals; p = 0.54), but higher perfusion in test animals versus controls during pacing (1.05 +/- 0.29 vs 0.69 +/- 0.09, test vs controls; p = 0.02). Increased myocardial endothelial cell density (42.6 +/- 8.5 vs 26.1 +/- 11.6 cells per 3850 microm2, test vs controls; p = 0.02) and expression of VE-cadherin (3.10 +/- 0.60-fold change, test vs controls; p = 0.001) were also observed in the lateral territory of test animals versus controls. Reconstitution of the proximally occluded circumflex artery from patch collaterals was demonstrated on gastroepiploic arteriography in a subset of test animals. CONCLUSIONS: This model results in an angiogenic process of significantly greater magnitude than that resulting from chronic myocardial ischemia alone, without the need for exogenous angiogenic agents. 相似文献
958.
The effect of vascular endothelial growth factor on the healing of ischaemic skin wounds. 总被引:7,自引:0,他引:7
F Zhang M P Lei T M Oswald Y Pang B Blain Z W Cai W C Lineaweaver 《British journal of plastic surgery》2003,56(4):334-341
The effect of exogenous vascular endothelium growth factor (VEGF) on wound healing in an ischaemic skin flap model was evaluated in this study. Seventy-two Sprague-Dawley rats were used. Normal incisional wound and H-shaped double flaps were used as the wound models. The study was divided into two parts. In Part I, VEGF protein levels were determined from the incisional and H-shaped ischaemic wounds at 12 and 24 h, postoperatively. In Part II, tensile strength and immunohistochemical stains were examined to determine the level of microvessel density (MVD) at 1 and 2 weeks, postoperatively in simple incisional wounds, ischaemic wounds, and ischaemic wounds following 1 ml (1 microg/ml) exogenous VEGF injections into the subcutaneous tissue. The results showed a significantly higher level of VEGF protein in the ischaemic wounds than the incisional wounds. Tensile strength was statistically higher in the incisional wound group and in the ischaemic flap wounds with VEGF treatment compared to the ischaemic flaps with no treatment at 1 week, postoperatively (p>0.05). MVD data indicated that ischaemic wound repair with VEGF treatment had significantly higher MVD than the normal incisional wounds and ischaemic wounds without treatment. We conclude that exogenous application of VEGF can increase early angiogenesis and tensile strength in the ischaemic wound. 相似文献
959.
960.
目的食管胃底静脉曲张动物模型的建立,对研究如何预防和治疗门脉高压征食管胃底静脉曲张出血具有重要意义。本研究目的在于建立犬门脉高压征食管静脉曲张动物模型并加以评价,为下一步探索临床治疗方法提供可靠、稳定的模型动物。方法10条健康成年雄性杂种犬为研究对象,以胆总管结扎术加CCl4法建立门脉高压征食管胃底静脉曲张动物模型。同时采用一系列的检查方法加以评估。结果10条犬存活8条,经胃镜检查证实,所有存活动物均形成食管静脉曲张,其中轻度2例,中度4例,重度2例。与术前相比,肝功能显著异常,门静脉压力明显升高,差异具有显著统计学意义(P<0.01)。门脉高压性胃病达58%。结论本组方法简单易行,模型质量可靠,制备周期明显缩短。该方法可形成稳定的肝硬化门脉高压征食管静脉曲张模型,可用于该方面的相关研究。 相似文献