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101.
基于统计参数图的脑功能磁共振成像数据处理方法 总被引:1,自引:0,他引:1
介绍了基于统计参数图的脑功能磁共振成像数据处理方法。脑功能磁共振成像由于其高的时间、空间分辨率、无创性等特点而得到广泛的应用。使用统计参数图进行脑功能成像的数据处理过程主要分为:原始数据的读取、图像预处理、统计分析和统计推论。图像预处理包括运动伪影的消除、图像标准化、图像空间平滑;统计分析包括广义线性模型的建立;统计推论包括T检验等。重点介绍了各个过程所使用的传统的处理方法和最新的处理方法。 相似文献
102.
103.
Determination of trace selenium in human body by anodic stripping voltammetry at gold-disc electrode
Summary For determination of trace Se we used high-pressure wet digester to pretreat the specimens obtained from the human body. This
method is very effective in preventing loss of Se by volatilization which often occurs in the sample pretreatment. We studied
the method of using anodic stripping voltammetry at gold-disc electrode to measure the trace Se present in the human body
and found it to be the optimal procedure. The detection limitation was about 2x10−8 g/L, the recovery rate of Se about 96.6±6,7 %
, and the coefficient of variation CV = 7.0%. 相似文献
104.
目的 观察应用尼卡地平预防双腔支气管导管插管心血管反应的效果。 方法 肺、食道择期手术病人 40例 ,随机分为 2组 ,每组 2 0例。咪唑安定 0 .0 4mg/kg、异丙酚 1.5mg/kg、芬太尼 4μg/kg、维库溴铵 0 .12mg/kg静脉诱导后 ,甲组给予尼卡地平 4μg/kg ,乙组给予生理盐水 3ml作为对照。分别于诱导前、后 ,插管后即刻及 1、3、5min监测收缩压 (SBP)、舒张压 (DBP)、心率 (HR) ,并计算心率收缩压乘积 (RPP)。 结果 A组插管后血压无明显升高 ,心率较诱导前无明显增快 ,B组插管后血压明显升高。 结论 尼卡地平可抑制双腔支气管导管插管时的心血管副反应。 相似文献
105.
目的:分析房室结慢径路消融术中出现的一过性交界性心律(JR)的特征。方法:21例(男6例,女15例)进行房室结改良术的房室结折返性心动过速患者,术中详细记录释放射频的次数、能量、持续时间、以及出现一过性交界性心律的时间、频率及数目,比较释放射频有效时/无效时出现的一过性交界性心律之特征有无显著性差异。结果:共进行106次射频电流释放,其中21次有效(A组),85次无效(B组)。A组有19次出现JR 相似文献
106.
107.
Justin Leube Anton Mühlbauer Immanuel Andrä Madleen Biggel Dirk H. Busch Lorenz Kretschmer Veit R. Buchholz 《European journal of immunology》2023,53(3):2250009
T cell ignorance is a specific form of immunological tolerance. It describes the maintenance of naivety in antigen-specific T cells in vivo despite the presence of their target antigen. It is thought to mainly play a role during the steady state, when self-antigens are presented in absence of costimulatory signals and at low density or to T cells of low affinity. In how far antigen-specific T cells can also remain clonally ignorant to foreign antigens, presented in the inflammatory context of systemic infection, remains unclear. Using single-cell in vivo fate mapping and high throughput flow cytometric enrichment, we find that high-affinity antigen-specific CD8+ T cells are efficiently recruited upon systemic infection. In contrast, most low-affinity antigen-specific T cells ignore the priming antigen and persist in the naïve state while remaining fully responsive to subsequent immunization with a high-affinity ligand. These data establish the widespread clonal ignorance of low-affinity T cells as a major factor shaping the composition of antigen-specific CD8+ T cell responses to systemic infection. 相似文献
108.
CT引导经皮肺穿刺锚状电极高温射频消融治疗肺部肿瘤105例 总被引:31,自引:1,他引:30
目的 观察CT引导经皮肺穿刺高温射频消融治疗105例肺部恶性肿瘤的近期效果。方法 CT引导经皮肺穿刺,可扩展锚状电极配合RF-2000仪高温射频消融治疗原发性肺癌81例,肺部转移瘤24例,共计242个肿瘤,每个肿瘤治疗3~8次,持续时间3~337min。结果 完全缓解(CR)率11.1%,部分缓解(PR)率71.1%,轻微疗效(MR)率13.2%,无改变(NC)率4.5%,其中CR+PR率为82. 相似文献
109.
Purpose. The genetic stability of a recombinant human factor VIII (rhFVIII) product expressed in Chinese hamster ovary cells (Recombinate) has been evaluated through comparisons of the protein produced at the beginning, middle and end of a typical production campaign.
Methods. Recombinant human factor VIII was incubated with thrombin, the resulting four polypeptides were isolated by RP-HPLC, subjected to proteolysis with trypsin, and the peptide mixtures were resolved by RP-HPLC. Tryptic peptide mixtures were subjected to online mass spectrometric analysis using an electrospray ionization source interfaced to a quadrupole mass analyzer scanning from 1950–200 amu, and the peptide ion data were compared for three lots produced from the beginning, middle and end of a production campaign.
Results. The UV elution profiles for each of the rhFVIIIa polypeptides were highly similar for factor VIII isolated from the beginning, middle and end of production. Total ion data from the peptide maps derived from three lots of rhFVIII were compared by MH1+ values as a function of scan range. A total of 918 ions were analyzed for the four polypeptides of rhFVIII produced at the beginning, middle and end of a production campaign. The ions were detected at the same relative retention times, as indicated by the similar scan numbers for the three lots.
Conclusions. These observations support that rhFVIII preparations produced from the beginning, middle and end of a production campaign were highly similar, and demonstrate genetic stability in the manufacturing process of Recombinate. 相似文献
110.
Darouiche RO Hampel OZ Boone TB Raad II 《International journal of antimicrobial agents》1997,8(4):243-247
The main objective of this study was to examine the antimicrobial activity and durability of a novel indwelling bladder catheter impregnated with minocycline and rifampin. Thirty antimicrobial-impregnated bladder catheters were inserted transurethrally in spinal cord-injured patients and removed, in six groups of five catheters each, at 3, 7, 10, 14, 17 or 21 days. Removed catheters had detectable zones of inhibition against two different clinical isolates of each of the 10 tested uropathogens (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter diversus, Enterococcus faecalis, Enterococcus faecium, Staphylococcus saprophyticus and Candida albicans) for greater than 14 days after catheter insertion. The residual zones of inhibition and levels of antimicrobial agents in removed catheters were both inversely related to the duration of catheter placement. Minocycline and rifampin were undetectable in serum and urine. These results support the ongoing efforts for examining the clinical efficacy of these experimental bladder catheters. 相似文献