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991.
高迁移率族蛋白B1对大鼠脾脏树突状细胞表面共刺激分子表达的影响 总被引:10,自引:1,他引:9
目的观察高迁移率族蛋白B1(HMGB1)对树突状细胞(dendritic cells,DC)表面共刺激分子表达的影响,并对其机制进行初步探讨。方法分离正常Wistar大鼠脾脏DC后置于96孔培养板(1×10~5/孔),采用HMGB1刺激,观察HMGB1刺激与DC表面共刺激分子CD80、CD86和主要组织相容性复合物(MHC)Ⅱ表达的时间-效应关系及剂量-效应关系。结果HMGB1刺激后,DC表面共刺激分子CD80、CD86和MHCⅡ表达分别于24~72 h明显上调(P<0.05,0.01),其中以作用48 h后DC表面共刺激分子表达上调尤为显著(P<0.01);0.1μg/ml、1μg/ml、10μg/ml的HMGB1刺激均可诱导DC表面共刺激分子CD80、CD86和MHCⅡ表达增强(P<0.05,0.01),其中HMGB1的浓度在1μg/ml时,大鼠DC表面共刺激分子CD80、CD86和MHCⅡ的表达增强最明显(P<0.01)。结论HMGB1能诱导DC表面共刺激分子表达增强,HMGB1可能是诱导DC成熟的免疫刺激信号。 相似文献
992.
颈动脉分叉血液动力状态的计算流体力学初步研究 总被引:3,自引:2,他引:1
目的应用计算流体力学(CFD)方法结合血管影像显示在体颈动脉分叉的血流动力状态.方法选取1例志愿者,采用Siemens多层螺旋CT机行左侧颈动脉CT血管成像检查(CTA),扫描所得原始图像经计算机后处理后,用CFD方法计算并显示血液动力学各项指标.结果(1)该血管血液流率均值范围为0.04~0.36 m/s,颈外和颈内动脉的内侧壁(均以分叉顶点为参照)可见一高血流速区,球部可见较大片低血流速区;颈动脉分叉及颈内、外动脉近端均可见血液涡流与回流.(2)血液绝对压、静态压和动态压的均值范围分别为100 266.70~101 615.90 Pa、-10 58.34~290.88 Pa、6.12~553.25 Pa;(3)管壁切应力均值范围为0.59~5.35 Pa,在颈动脉球部及颈内动脉后壁显示大范围的低切应力区,最低约为0.25 Pa,颈外动脉前外侧壁存在一小范围低切应力区.结论CFD方法结合血管影像能计算并显示在体颈动脉分叉的个体化血液动力学指标. 相似文献
993.
目的 分析主观症状及实验检查对早期干眼症患者诊断的意义。方法 对55例(109眼)已确诊的早期干眼症患者(无或仅伴有轻微体征)的临床症状及实验检查进行回顾性分析及比较。结果 患者中主观症状所占比率:干涩感94%,视疲劳感82%,异物感74%,明显高于其他症状(P〈0.05)。实验检查的阳性率:基础泪液分泌试验(Schirmer I test,SIt)35%,泪膜破裂时间检查(break-up time,BUT)85%,角结膜荧光素(fluorescent,FL)染色60%,其中BUT阳性率明显高于SIt和FL(P〈0.05)。结论 主观症状及实验检查可为早期干眼症诊断提供有利依据。 相似文献
994.
Margaret A. O’Leary Brian Prakash Krishnan Amy McKendry Geoffrey K. Isbister 《Toxicon》2007,50(2):206-213
Recently it has been suggested that the Australian snake antivenoms made by CSL Ltd. are in fact not truly monovalent and may contain antibodies to other snake venoms because the horses are injected with multiple snake venoms. It is unclear to what extent various monovalent antivenoms can neutralise the effect of other venoms, whether this is due to a mixture of antibodies or true cross-reactivity, and whether this has any clinical significance. We aimed to study the immunological and functional properties of brown snake (Pseudonaja spp.) antivenom (BSAV) and tiger snake (Notechis spp.) antivenom (TSAV) against their respective venoms using enzyme immunoassays (EIA) and in vitro clotting studies. There was significant overlap between the two antivenoms with both TSAV and BSAV being detected by EIA on brown snake venom (BSV)-coated and tiger snake venom (TSV)-coated wells, respectively. In a competition EIA, increasing amounts of immunoaffinity-purified hen anti-brown antibodies (IgYp) mixed with TSAV reduced TSAV measured on TSV-coated wells. Both BSAV and TSAV prevented the clotting activity of both venoms. IgYp also prevented the clotting activity of TSV, suggesting true cross-reactivity. The cross-reactivity of TSAV and BSAV with BSV and TSV, respectively, was likely due to each being a mixture of anti-brown and anti-tiger antibodies, but there was partial cross-reactivity demonstrated by the effect of IgYp. Single-polyvalent antivenom for brown snake and tiger snake may be feasible in the future. 相似文献
995.
Chih-Yang Lin Wen-Jeng Lee Shyh-Jye Chen Ching-Hwa Tsai Jei-Han Lee Chia-Hung Chang Yu-Tai Ching 《Journal of digital imaging》2006,19(4):351-361
Computed radiography (CR) has many advantages such as filmless operations, efficiency, and convenience. Furthermore, it is
easier to integrate with the picture archiving and communication systems. Another important advantage is that CR images generally
have a wider dynamic range than conventional screen film. Unfortunately, grid artifacts and moiré pattern artifacts may be
present in CR images. These artifacts become a more serious problem when viewing CR images on a computer monitor when a clinic
grade monitor is not available. Images produced using a grid with higher frequency or a Potter–Bucky grid (i.e., a moving
grid, Bucky for short) can reduce occurrence but cannot guarantee elimination of these artifacts [CR & PACS (2000); Detrick
F (2001), pp 7–8]. In this paper, the formation of the artifacts is studied. We show that the grid artifacts occur in a narrow
band of frequency in the frequency domain. The frequency can be determined, accurately located, and thus removed from the
frequency domain. When comparing the results obtained from the proposed method against the results obtained using previous
computer methods, we show that our method can achieve better image quality. 相似文献
996.
997.
Bošnjaković Petar Ivković Tomislav Ilić Miodrag Aracki Snežana 《Cardiovascular and interventional radiology》1992,15(4):217-220
Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment
of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using
retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual
stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning.
We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to
PTA. 相似文献
998.
本文对40例住院高血压患者作了静息相及负荷相99mTc-MIBI心肌单光子发射计算机断层(SPECT)显像并采用门电路心血池显像(MGBP)评价室壁运动。结果显示:本组病例心肌灌注显像放射性稀疏缺损(MPD)发生率高达87.5%(35/40),其中可逆性(RPD)57.1%;有MPD者在MPD节段室壁运动异常发生率91.4%(32/35),但RPD组与非RPD组间无显著差异。文中对高血压患者心肌缺血及其导致MPD的机制进行了探讨,认为99mTc-MIBI心肌SPECT显像出现MPD是反映高血压患者心肌缺血的敏感方法,MGBP多指标评价室壁运动可揭示绝大多数MPD节段的室壁运动异常。 相似文献
999.
1000.
J. Viby Mogensen M.D. Ph.D. E. Jensen M. Werner H. Kirkegaard Nielsen 《Acta anaesthesiologica Scandinavica》1988,32(1):45-48
A new method for monitoring neuromuscular function based on measurement of acceleration is presented. The rationale behind the method is Newton's second law, stating that the acceleration is directly proportional to the force. For measurement of acceleration, a piezo-electric ceramic wafer was used. When this piezo electrode was fixed to the thumb, an electrical signal proportional to the acceleration was produced whenever the thumb moved in response to nerve stimulation. The electrical signal was registered and analysed in a Myograph 2000 neuromuscular transmission monitor. In 35 patients anaesthetized with halothane, train-of-four ratios measured with the accelerometer (ACT-TOF) were compared with simultaneous mechanical train-of-four ratios (FDT-TOF). Control ACT-TOF ratios were significantly higher than control FDT-TOF ratios: 116 +/- 12 and 98 +/- 4 (mean +/- s.d.), respectively. In five patients not given any relaxant during the anaesthetic procedure (20-60 min), both responses were remarkably constant. In 30 patients given vecuronium, a close linear relationship was found during recovery between ACT-TOF and FDT-TOF ratios. It is concluded that the method fulfils the basic requirements for a simple and reliable clinical monitoring tool. 相似文献