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111.
Bing Feng P. Hendrik Pretorius Troy H. Farncombe Seth T. Dahlberg Manoj V. Narayanan Miles N. Wernick Anna M. Celler Jeffrey A. Leppo Michael A. King 《Journal of nuclear cardiology》2006,13(3):354-361
BACKGROUND: Dynamic single photon emission computed tomography (SPECT) acquisition and reconstruction of early poststress technetium 99m teboroxime washout images has been shown to be useful in the detection of coronary disease. Assessment of poststress regional wall motion may offer additional use in assessing coronary disease. Our goal was to investigate the feasibility of simultaneously imaging myocardial ischemia and transient poststress akinesis using gated-dynamic SPECT. METHODS AND RESULTS: A gated-dynamic mathematical cardiac torso (MCAT) phantom was developed to model both teboroxime kinetics and cardiac regional wall motion. A lesion was simulated as having delayed poststress teboroxime washout together with a transient poststress wall motion abnormality. Gated projection data were created to represent a 3-headed SPECT system undergoing a total rotation of 480 degrees . The dynamic expectation-maximization reconstruction algorithm with postsmoothing across gating intervals by Wiener filtering, and the ordered-subset expectation maximization reconstruction algorithm with 3-point smoothing across gating intervals were compared. Compared with the ordered-subset expectation maximization with 3-point smoothing, the dynamic expectation-maximization algorithm with Wiener filtering was able to produce visually higher-quality images and more accurate left ventricular ejection fraction estimates. CONCLUSION: From simulations, we conclude that changing cardiac function and tracer localization possibly can be assessed by using a gated-dynamic acquisition protocol combined with a 5-dimensional reconstruction strategy. 相似文献
112.
目的探讨定量测定肝癌患者血清12种肿瘤标志物的临床意义。方法用蛋白芯片技术定量测定42例正常人、46例肝癌、41例肝炎和23例肝硬化患者血清12种肿瘤标志物的变化并对检测效果进行评价。结果42例正常人CA-199(KU/L)、NSE(g/L)、CEA(g/L)、CA-242(KU/L)、Ferritin(g/L)、β-HCG(g/L)、AFP(g/L)、f-PSA(g/L)、PSA(g/L)、CA-125(KU/L)、HGH(g/L)和CA-153(KU/L)的含量分别为12.42±10.62、2.22±1.43、1.28±1.20、5.72±5.73、91.17±79.43、0.64±0.34、2.96±3.93、0.13±0.11、0.61±1.40、5.46±9.65、1.61±2.40、9.83±9.51;46例肝癌患者血清12种肿瘤标志物含量依次为:35.09±39.50、2.83±4.13、2.98±8.72、8.47±23.42、157.50±129.77、0.72±0.72、87.58±63.27、0.15±0.19、0.58±1.88、56.34±102.02、3.63±4.57、15.65±51.09;41例肝炎患者其含量依次为:76.23±96.57、4.12±4.94、2.06±3.92、4.68±6.99、298.76±326.82、1.00±0.74、63.16±91.76、0.11±0.006、0.27±0.94、18.57±36.60、3.63±4.00、6.13±6.86;23例肝硬化患者其含量依次为:49.85±75.60、5.47±14.97、1.71±1.77、12.44±34.55、278.32±326.82、0.70±0.54、52.89±98.28、0.22±0.21、2.24±4.36、111.50±191.99、2.15±0.99、10.51±15.79。该蛋白芯片测定的敏感性为50.0%,特异性为64.2%,阳性预测值为37.7%,阴性预测值为74.7%。结论采用蛋白芯片技术同时测定患者血清多种肿瘤标志物,对普查肿瘤和临床疗效观察有较好应用价值。 相似文献
113.
对不孕症患者进行碘化油输卵管造影检查是临床上经常需要做的一种检查,以往施行输卵管碘化油造影是在X线照射下,由于造影需要时间较长,医患双方都会接受大量X线照射,不利于身体健康。我院自2002年1月~2003年3月,对30例不孕症患者,利用B超经腹壁,在实时观察引导下行碘化油输卵管造影术,现总结报告如下。1材料与方法本组患者年龄在25~45岁,均经临床妇科检查及B超常规检查,经输卵管通液及药物治疗无效者。其中原发不孕5例,继发不孕25例。采用东芝公司的SSH-140A型超声诊断仪,探头频率3·75MHz。窥阴器、宫颈钳、宫颈导管、20ml或30ml注射器… 相似文献
114.
运用市场手段实现医药自然分开的理论探讨 总被引:1,自引:0,他引:1
回顾了韩国、我国台湾和大陆实行医药分开改革的过程,认为我国以往的相关改革陷入了“管制”的思维误区。认为通过制度设计,创造医疗机构门诊处方自由流动的环境,依靠市场竞争形成处方流向结构多元化,可以实现医药自然分开状态。提出了“医药自然分开”、“处方流向结构”和“处方分散度”等新概念。 相似文献
115.
116.
菜豆角内含豆素和皂毒等有毒物质,前者具有凝血作用,加热可破坏,后者刺激黏膜可致溶血,食入大量未熟透菜豆角可致中毒。我县城某中学学生在本校食堂食入未煮熟的菜豆角,造成91例中毒,经我院医护人员积极抢救,全部患儿转危为安。现将抢救及护理体会介绍如下。 相似文献
117.
Noriyo Kimura Satomi Yonemoto Toshihiko Machiguchi Xuan Li Hideki Kimura Haruyoshi Yoshida 《Hypertension research》2006,29(8):573-580
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis. 相似文献
118.
阻塞性黄疸大鼠肾脏自分泌内皮素的变化及其与肾功能损害的关系 总被引:3,自引:1,他引:2
目的 探讨阻塞性黄疸时肾脏自分泌内皮素 (ET)的变化及其与肾功能损害的关系。方法 结扎胆总管(BDL)制备阻塞性黄疸大鼠模型 ,作为实验组 ,对照组鼠仅行假手术。分别于术后 5、1 0及 1 5d ,两组各取 1 0只大鼠检测其肾脏对氨基马尿酸清除率 (CPAH)、菊粉清除率 (CIN)和钠排泄分数 (FENa+) ,并用鲎试剂法测定血浆内毒素 (EX)水平 ,放射免疫法测定肾动、静脉血浆及肾组织中ET 1含量。结果 ①实验组术后 5d仅FENa+明显高于对照组 (P<0 .0 1 ) ,术后 1 0d起 ,CPAH、CIN及FENa+呈进行性下降 ,术后 1 5dFENa+已较对照组低 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;②实验组术后血浆EX水平呈进行性升高 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;③实验组术后肾动脉血浆ET 1水平呈持续性降低 ,而肾静脉血浆及肾组织中ET 1含量呈持续性升高 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;④血浆EX水平与肾组织ET 1含量呈正相关 (r =0 .762 4 ,P<0 .0 1 ) ,肾组织ET 1含量与CPAH和CIN呈负相关 (r=- 0 .883 2 ,P<0 .0 1 ;r =- 0 .945 2 ,P<0 .0 1 )、与FENa+呈正相关 (r=0 .873 4 ,P<0 .0 1 )。结论 内毒素血症及其诱导的肾内ET分泌增加在阻塞性黄疸所致大鼠肾损害中可能具有重要作用 相似文献
119.
120.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献