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101.
目的:评价肿瘤坏死因子α拮抗剂阿达木单抗短期治疗类风湿关节炎(RA)的临床疗效及安全性,同时检测治疗前后类风湿因子(RF)和抗环瓜氨酸肽抗体(抗CCP抗体)滴度的变化,为RA疗效评估寻找新的指标。方法:随机双盲平行试验,纳入40例活动性RA患者,按2∶2∶1的比例被随机分配到试验组或对照组,试验组分为80 mg阿达木单抗+甲氨喋呤(MTX)、40 mg阿达木单抗+MTX两组,对照组为安慰剂+MTX。受试者隔周接受皮下注射阿达木单抗或同等体积的安慰剂,并在试验第0,2,4,8,12周随访,评价疗效及不良事件收集。疗效采用ACR核心标准评定。次要疗效指标包括压痛和肿胀关节数、晨僵时间、疼痛视觉模拟评分(VAS评分)、健康评估问卷(HAQ)和CRP。基线时及12周治疗结束后检测RF、抗CCP抗体。结果:试验组32例,对照组8例。12周后试验组患者ACR20、ACR50和ACR70缓解的比例都显著高于对照组(P<0.01);试验组患者关节触痛数、关节肿胀数、晨僵持续时间、疼痛VAS评分及健康状况问卷(HAQ)、CRP等次要疗效指标均较基线时水平明显降低(P<0.05);试验组RF血清滴度和抗CCP抗体均较基线时水平显... 相似文献
102.
采用射频反应溅射法在玻璃衬底上制得均匀透明的TiO2纳米薄膜,通过离子溅射仪在纯TiO2薄膜上制备银包覆TiO2复合薄膜.利用X射线衍射分析(XRD)、扫描电子显微镜(SEM)等表征技术研究了银包覆TiO2薄膜的晶体结构和表面形貌.XRD和SEM观测结果显示:射频功率为250 W时,薄膜表面光滑平整,颗粒均匀,大小在3... 相似文献
103.
血清抗CCP抗体、抗AKA抗体及RF在类风湿关节炎诊断中的价值 总被引:4,自引:0,他引:4
【摘要】目的血清抗CCP抗体、抗AKA抗体及RF在类风湿关节炎诊断中的价值。方法检测108例类风湿关节炎(RA)患者、138例非RA风湿病患者(非RA组)及40例健康人(对照组)血清中抗环瓜氨酸肽(CCP)抗体(简称抗CCP)、抗AKA抗体(简称抗AKA)水平,并与类风湿因子(RF)比较。结果抗CCP抗体的阳性率在RA中为80.6%,在非RA中为3.4%,3种抗体对RA诊断的敏感性分别为CCP81.5%;AKA42.6%;RF74.1%。抗CCP抗体与AKA、RF之间显著相关(P〈0.01)。严重关节侵蚀、关节肿痛RA患者,抗CCP抗体水平高于形轻微关节侵蚀、关节肿痛RA患者,两组比较,抗CCP抗体水平差异有统计学意义(P〈0.01)。结论抗CCP抗体对RA诊断具有很高的临床应用价值;抗CCP抗体水平的检测有助于预后判断,有望替代AKA与经典指标RF联合检测。认为抗CCP和抗AKA有助于不典型RA(特别是RF阴性的RA)的诊断,在一定程度上可弥补RF对RA诊断不足。三种抗体联合检测可提高RA的诊断率。 相似文献
104.
105.
EUS spectrum analysis for in vivo characterization of pancreatic and lymph node tissue: a pilot study 总被引:1,自引:0,他引:1
Kumon RE Olowe K Faulx AL Farooq FT Chen VK Zhou Y Wong RC Isenberg GA Sivak MV Chak A Deng CX 《Gastrointestinal endoscopy》2007,66(6):1096-1106
BACKGROUND: EUS is limited by variability in the examiner's subjective interpretation of B-scan images to differentiate among normal, inflammatory, and malignant tissue. By using information otherwise discarded by conventional EUS systems, quantitative spectral analysis of the raw radiofrequency (RF) signals underlying EUS images enables tissue to be characterized more objectively. OBJECTIVE: Our purpose was to determine the feasibility of using spectral analysis of EUS data for characterization of pancreatic tissue and lymph nodes. DESIGN AND SETTING: A pilot study of eligible patients was conducted to analyze the RF data obtained during EUS by using spectral parameters. PATIENTS: Twenty-one subjects who underwent EUS of the esophagus, stomach, pancreas, and surrounding intra-abdominal and mediastinal lymph nodes. MAIN OUTCOME MEASUREMENTS: Linear regression parameters of calibrated power spectra of the RF signals were tested to differentiate normal pancreas from chronic pancreatitis and from pancreatic cancer as well as benign from malignant-appearing lymph nodes. RESULTS: The mean intercept, slope, and midband fit of the spectra differed significantly among normal pancreas, adenocarcinoma, and chronic pancreatitis when all were compared with each other (P < .01). On direct comparison, mean midband fit for adenocarcinoma differed significantly from that for chronic pancreatitis (P < .05). For lymph nodes, mean midband fit and intercept differed significantly between benign- and malignant-appearing lymph nodes (P < .01 and P < .05, respectively). LIMITATIONS: Small sample population and spatial averaging inherent to this technique. CONCLUSIONS: Mean spectral parameters in EUS imaging can provide a noninvasive method to discriminate normal from diseased pancreas and lymph nodes. 相似文献
106.
107.
108.
Murakami T Ishimaru H Sakamoto I Uetani M Matsuoka Y Daikoku M Honda S Koshiishi T Fujimoto T 《Cardiovascular and interventional radiology》2007,30(4):696-704
PURPOSE: To analyze local recurrence-free rates and risk factors for recurrence following percutaneous radiofrequency ablation (RFA) or transcatheter arterial chemoembolization (TACE) for hypervascular hepatocellular carcinoma (HCC). METHODS: One hundred and nine nodules treated by RFA and 173 nodules treated by TACE were included. Hypovascular nodules were excluded from this study. Overall local recurrence-free rates of each treatment group were calculated using the Kaplan-Meier method. The independent risk factors of local recurrence and the hazard ratios were analyzed using Cox's proportional-hazards regression model. Based on the results of multivariate analyses, we classified HCC nodules into four subgroups: central nodules < or =2 cm or >2 cm and peripheral nodules < or =2 cm or >2 cm. The local recurrence-free rates of these subgroups for each treatment were also calculated. RESULTS: The overall local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p = 0.013). The 24-month local recurrence-free rates in the RFA and TACE groups were 60.0% and 48.9%, respectively. In the RFA group, the only significant risk factor for recurrence was tumor size >2 cm in greatest dimension. In the TACE group, a central location was the only significant risk factor for recurrence. In central nodules that were < or =2 cm, the local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p < 0.001). In the remaining three groups, there was no significant difference in local recurrence-free rate between the two treatment methods. CONCLUSION: A tumor diameter of >2 cm was the only independent risk factor for local recurrence in RFA treatment, and a central location was the only independent risk factor in TACE treatment. Central lesions measuring < or =2 cm should be treated by RFA. 相似文献
109.
Vijayanand Alagappan Juergen Nistler Elfar Adalsteinsson Kawin Setsompop Ulrich Fontius Adam Zelinski Markus Vester Graham C Wiggins Franz Hebrank Wolfgang Renz Franz Schmitt Lawrence L Wald 《Magnetic resonance in medicine》2007,57(6):1148-1158
An eight-rung, 3T degenerate birdcage coil (DBC) was constructed and evaluated for accelerated parallel excitation of the head with eight independent excitation channels. Two mode configurations were tested. In the first, each of the eight loops formed by the birdcage was individually excited, producing an excitation pattern similar to a loop coil array. In the second configuration a Butler matrix transformed this "loop coil" basis set into a basis set representing the orthogonal modes of the birdcage coil. In this case the rung currents vary sinusoidally around the coil and only four of the eight modes have significant excitation capability (the other four produce anticircularly polarized (ACP) fields). The lowest useful mode produces the familiar uniform B(1) field pattern, and the higher-order modes produce center magnitude nulls and azimuthal phase variations. The measured magnitude and phase excitation profiles of the individual modes were used to generate one-, four-, six-, and eightfold-accelerated spatially tailored RF excitations with 2D and 3D k-space excitation trajectories. Transmit accelerations of up to six-fold were possible with acceptable levels of spatial artifact. The orthogonal basis set provided by the Butler matrix was found to be advantageous when an orthogonal subset of these modes was used to mitigate B(1) transmit inhomogeneities using parallel excitation. 相似文献
110.
PURPOSE: To demonstrate the effects of inherent RF inhomogeneity on ramped RF excitation at 3.0T, and to introduce a simple correction for improving visualization of distal intracranial arteries in three-dimensional time-of-flight MR angiography (3D-TOF-MRA). MATERIALS AND METHODS: At 3.0T, the effects of RF inhomogeneity arising from RF interference were demonstrated for ramped RF excitation in intracranial 3D-TOF-MRA. Computer simulations and experiments on phantoms and eight normal volunteers were performed. Four different ramp shapes were tested as a possible means of countering the reduced RF field that affects the distal intracranial arteries. RESULTS: RF destructive interference alters the ramp pulse shape, which is problematic for vessels that proceed from the center to the edge of the brain. Increasing the ramp pulse slope was shown to be an effective yet simple correction to counter the falling-off of the RF field toward the periphery of the head. With this approach, circle-of-Willis 3D-TOF-MRA studies had improved distal visibility. CONCLUSION: Ramped RF excitation is severely affected by RF interference at 3.0T, which makes the ramp profile suboptimal for distal intracranial blood vessels. A simple correction of the ramp slope can make a marked improvement. 相似文献