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51.
Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia. 总被引:3,自引:0,他引:3
Xian Nan Tang Qing Wang Maya A Koike Danye Cheng Michael L Goris Francis G Blankenberg Midori A Yenari 《Journal of nuclear medicine》2007,48(11):1822-1828
Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia. 相似文献
52.
QIN Jian LIU Hong-jian DENG Wei WU Guo-zhen CHEN Shu-qing JING Ming-hua 《中国生物医学工程学报(英文版)》2005,14(3):114-119
Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN (Stochastic Fuzzy Neural Network) is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers. 相似文献
53.
本文F30-IIB型X线机将对以下两种常见故障进行简要分析:①X线机mA表指针出现倒退②mA表指针一直指在满刻度位置。 相似文献
54.
准分子激光原位角膜磨镶术患者主客观因素与疗效的相关性分析 总被引:3,自引:1,他引:2
目的:通过对准分子激光原位角膜磨镶术(LASIK)患者主客观因素与疗效的相关性分析,了解临床影响术后视力的主观、客观因素。方法:对2002年间在我院行ASIK的164例患者325只眼(其中3例为单眼)进行连续性临床观察研究,分别进行术前、术后问卷式主客观因素调查,并对患者手术疗效进行相关性统计学分析。结果:患者术前对手术效果的期望值、手术中疼痛程度与手术后视力有显著相关性。结论:解除患者术前忧虑及避免术中疼痛对提高术后疗效有重要意义。 相似文献
55.
Performance measurement of the microPET focus 120 scanner. 总被引:6,自引:0,他引:6
Jin Su Kim Jae Sung Lee Ki Chun Im Su Jin Kim Seog-Young Kim Dong Soo Lee Dae Hyuk Moon 《Journal of nuclear medicine》2007,48(9):1527-1535
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals. 相似文献
56.
目的 探讨过氧化物酶体增殖物对小鼠原代肝细胞生长周期的影响和配体过氧化物酶体增殖物激活受体(proxisome proliferators—activated receptor,PPAR)alpha在肝癌形成过程中的变化。方法 在小鼠原代肝细胞中加入PPAR配体Wy-14,643,经不同培养时间后,应用流式细胞仪、逆转录-聚合酶链反应及Western blot等方法检测细胞增殖和凋亡,细胞周期蛋白p21WAFI、cyclinD1的mRNA及蛋白的变化情况。结果 在小鼠原代肝细胞中加入Wy-14,643培养2、4、6d,S+G2/M期细胞比例分别为(42.3±1.2)%,(50.3±2.1)%,(52.1±2.3)%,细胞凋亡率分别(9.0±0.2)%,(7.9±2.O)%,(7.4±1.3)%,与未加药组相比,细胞增殖明显增高(P〈0.05),凋亡明显减少(P〈0.05);各加药组cylinD1 mRNA和蛋白的表达也比对照组明显增高(P〈0.05);各加药组p21^WAF1 mRNA与对照组相比表达无显著变化(P〉0.05),第4天开始出现p21^WAF1。蛋白的表达显著增加(P〈0.05)。结论 过氧化物酶体增殖物通过其配体PPARα引起细胞周期蛋白的改变,导致正常细胞周期信号的传导紊乱,引起细胞异常的增殖和凋亡,从而有可能诱发肿瘤。 相似文献
57.
不同方法治疗特殊部位白癜风疗效的比较 总被引:1,自引:0,他引:1
目的通过不同方法治疗特殊部位白癜风的疗效观察,以便筛选出对不同部位白癜风的最佳治疗方法.方法随机将l 22例(375区白斑)特殊部位白癜风患者分为5组,移植微型毛胚组42例,磨削去除白斑组52例,毛囊刮取物注射组35例,液氮冷冻起疱去除白斑组30例,外用药物治疗组45例.观察其疗效,对各组病例统一疗效标准判断,统计学处理.结果移植微型毛胚组总有效率97.1 %,磨削去除白斑组总有效率94.7 %,毛囊刮取物注射组总有效率59.7 %,液氮冷冻起疱去除白斑组总有效率57.1%,外用药物治疗组总有效率45.5 %.经统计学处理,各组之间比较,差异有非常显著性意义(χ^2=111.77,P<0.005).结论特殊部位白癜风的治疗,目前仍是一个棘手的问题,上述所介绍的方法无疑是在实践中切实可行的方法,各有特色,可以根据不同部位,酌情选择最佳方法,也可以联合应用,相互补充,提高疗效. 相似文献
58.
目的 探讨疝环充填式无张力修补术治疗腹股沟疝的经验并评价其临床价值.方法 回顾总结2000年1月至2007年6月疝环充填式无张力修补术治疗腹股沟疝262例临床资料,其中伴随高血压、冠心病、糖尿病、慢性呼吸系统疾病、便秘、前列腺肥大等238例,占90.8%.结果 全组均治愈,手术时间平均41分钟,无切口感染,术后4~7天出院,平均住院5天,随访3~64个月,疝复发1例,为0.4%.结论 该方法操作简便,符合腹股沟区生理解剖特点,强调对高龄患者的术前准备,强调严格的无菌操作,强调充填物放置到位和充填后修补到位是避免术后复发的关键. 相似文献
59.
目的探讨季德胜蛇药外敷治疗化疗药物外渗致局部损伤的效果。方法将12只雌性新西兰成年兔随机分为环磷酰胺(CTX)组、重酒石酸长春瑞滨(NVB)组和阿霉素(ADM)组各4只,分别将CTX、NVB、ADM注入兔的四肢血管周围建立化疗药物外渗模型,从每种模型中随机选择2只兔分别采用50%硫酸镁溶液和1∶5000呋喃西林加季德胜蛇药外敷外渗局部,并进行肉眼观察和组织学观察。结果1∶5000呋喃西林加季德胜蛇药外敷后局部肿胀消退指数显著高于50%硫酸镁溶液湿敷(均P〈0.01),且炎性反应明显减轻。结论1∶5000呋喃西林加季德胜蛇药外敷治疗化疗药物外渗可明显减轻局部炎性反应,是一种有效的处理方法。 相似文献
60.
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