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Findings of CT of the spleen were compared with those of histologic examination in 35 patients who had Hodgkin disease. CT provides a simple way to calculate splenic size. This index is also of value in the assessment of the histologic state of the spleen. An accuracy rate of 91%, specificity of 94%, and a sensitivity of 89% in diagnosing splenic localization of lymphoma was found in this study. 相似文献
144.
HPLC柱切换法血浆直接进样测定糖肾平 总被引:9,自引:0,他引:9
采用HPLC柱切换技术,以Merck Lichroprep RP2(25~40μm)为预处理柱填料,以水为预处理流动相,以0.2mol/L乙酸-乙酸铵为净化清洗液,血浆直接进样,在线富集净化样品。血浆样品以0.2ml/min慢速转移通过预处理柱,净化回收率达80%。以ShimpackCLC-ODS为分析柱(15cm×6mm,ID),甲醇-异丙醇-0.2mol/L 乙酸铵(61:5:34)为分析流动相,310nm波长检测,外标法定量测定人体血浆中糖肾平的浓度。血浆样品仅需稀释后即可进样,净化富集样品操作简便,预处理柱可长期反复进样使用。血浆中最低检测浓度为30ng/ml,日内变异系数为2.0%~5.4%,日间变异系数为2.4%~2.7%,在浓度为60~2020ng/ml血浆范围内呈线性关系。 相似文献
145.
Peripheral pulmonary lesions: ultrasonography and ultrasonically guided aspiration biopsy 总被引:8,自引:0,他引:8
Twenty-five patients, each of whom had peripheral intrathoracic lesions that were smaller than 5.0 X 5.0 cm in size and not diagnosed by conventional methods, underwent real-time sonography and ultrasonically guided aspiration biopsy. The lesions included 18 nodules, two infiltrates, and five cavitary lesions. Sonography showed homogeneous hypoechoic or isoechoic density with well-defined margins in 16 of the nodules, and heterogeneous echogenicity with irregular margins in infiltrates. The cavitary lesions showed a hyperechoic ring with a central sonolucent area. Biopsy specimens were successfully obtained by percutaneous aspiration under ultrasound guidance in 24 (96%) of the patients, and a positive diagnosis was established in 21 (84%) by cytology and/or histology. All 17 malignant lesions were diagnosed by aspiration biopsy, while only four of seven benign lesions were diagnosed by this method. Two patients (8%) experienced minimal pneumothorax after aspiration biopsy. We conclude that real-time sonography, including ultrasonically guided aspiration biopsy, is a useful and safe method for examination of peripheral intrathoracic lesions and has a high diagnostic yield. 相似文献
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研究背景 处于宫内发育期间的胎儿如果患有先天性心脏畸形 ,心脏畸形可能逐渐加重 ,因此胎儿心脏外科干预治疗具有潜在的发展空间。怀孕期间实施畸形纠治可能预防由于病理性的血流方式所导致的心腔或大血管发育不良。但是 ,对最佳的胎儿心肌保护研究策略尚未进行深入研究。本研究应用胎儿双心室工作模型 ,对诱导性心室纤颤和晶体停搏液灌注的心肌保护效果进行对比评估。方法 实验用心脏取自孕龄 115~ 12 5天的胎羊。使用Krebs-Henseleit溶液灌注离体心脏。在动脉导管以远结扎降主动脉 ,肺动脉侧枝均结扎以模拟胎儿循环。 1组离体心脏采用常温诱导性心室纤颤 (n =8) ,另外 1组采用低温晶体停搏液灌注使得心脏停搏 (n =8)。之后均恢复Krebs -Henseleit溶液灌注。通过压力直径关系曲线测定心脏停搏前的心功能基础值以及停搏后的心功能指数。结果 停搏后的心脏收缩功能指数检测显示 ,诱导性心室纤颤与晶体停搏液具有相同的心肌保护效果(停搏后左心室收缩指数分别为 70 %± 5 %vs 6 8%± 15 % ,P =0 .5 2 ;右心室收缩指数分别为 6 8%± 4 .5 %vs 6 5 %± 4 .5 % ,P =0 .2 6 )。对于预防舒张期室壁张力的增加 ,两者的作用相似 (左心室分别为 32 %± 5 .3%vs 38%± 11% ,P =0 .2 4 ;右心室分别为 2 5 %± 3 相似文献
148.
Background: The diagnosis in cases of mediastinal and/or hilar lymphadenopathy with no lung parenchymal involvement is often difficult. We undertook this study to assess the diagnostic value of flexible bronchoscopy (FOB) especially transbronchial needle aspiration (TBNA) and transbronchial lung biopsy (TBLB) in these patients. 相似文献
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150.
Meningeal cell-derived semaphorin 3A inhibits neurite outgrowth 总被引:5,自引:0,他引:5
Niclou SP Franssen EH Ehlert EM Taniguchi M Verhaagen J 《Molecular and cellular neurosciences》2003,24(4):902-912
The neural scar that forms after injury to the mammalian central nervous system is a barrier to sprouting and regenerating axons. In addition to reactive astrocytes that are present throughout the lesion site, leptomeningeal fibroblasts invade the lesion core. When isolated in vitro, these cells form a very poor substrate for growing neurites, even more so than reactive astrocytes. Nevertheless the molecular mechanisms involved in this growth inhibition are not well understood. Semaphorins have been reported to be upregulated in meningeal cells (MCs) on mechanical injury to the brain and spinal cord. In the present study, we show that Sema3A mRNA and active protein are produced by cultured meningeal cells. A protein extract from these cells induces the collapse of embryonic dorsal root ganglion (DRG) growth cones. This collapsing activity is partially blocked by neuropilin-1 antibodies and is absent in meningeal cells derived from Sema3A-knockout mice. In addition to growth cone collapse, recombinant Sema3A but not Sema3C inhibits neurite outgrowth of embryonic DRGs. Consistent with this result we find that the inhibitory effect of meningeal cells on neurite outgrowth is partially overcome on Sema3A-deficient MCs. Furthermore we show that the inhibitory effect of MC-derived Sema3A on neurite outgrowth is modulated by nerve growth factor. Our results show that Sema3A, a chemorepellent during nervous system development, is a major neurite growth-inhibitory molecule in meningeal fibroblasts and is therefore likely to contribute to the inhibitory properties of the neural scar. 相似文献