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排序方式: 共有71条查询结果,搜索用时 140 毫秒
1.
We describe a case of serum amyloid A (SAA) and C‐reactive protein (CRP) positive nodule detected by immunohistochemical analysis in a 37‐year‐old woman with alcohol‐related cirrhosis. Imaging studies at first admission pointed to hepatocellular carcinoma (HCC), a dysplastic nodule, an inflammatory pseudotumor or focal nodular hyperplasia (FNH). Ultrasonography‐guided biopsy in Segment 2 showed minimal atypical changes, except for a slight increase in cell density and micronodular cirrhosis in the non‐nodular portion. gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid‐enhanced magnetic resonance imaging carried out after a year and a half revealed hypervascularity in the arterial phase and isointensity in the hepatobiliary phase. Three years thereafter, however, the imaging displayed a change from isointensity to a defect in the hepatobiliary phase, and the nodule demonstrated minimal histological atypia. Immunohistochemical staining of the nodule was positive for SAA, CRP, liver fatty acid‐binding protein and glutamine synthetase, but negative for β‐catenin, heat shock protein 70 and Glypican 3. Organic anion transporter (OATP)8 staining was weaker in the nodule than in the non‐nodular portion of the alcohol‐related micronodular cirrhosis. The nodule was diagnosed as an SAA and CRP positive nodule, and HCC was ruled out. Despite the change from isointensity to a defect in the hepatobiliary phase, no evidence of HCC was found in the biopsy specimen. The change may be explained more by the weak OATP8 staining compared with that of alcohol‐related liver cirrhosis than by malignant transformation into HCC.  相似文献   
2.
目的 探讨钆塞酸二钠(Gd-EOB-DTPA)增强MRI影像组学对肝血管瘤腹腔镜肝切除术疗效的预测价值。方法 选取2018年2月至2020年10月行腹腔镜肝切除术治疗的肝血管瘤患者131例作为研究对象。采用计算机产生随机数法将131例肝血管瘤患者以7:3的比例分为训练集(92例)和验证集(39例),分别用于构建和验证预测模型效能。根据术后是否出现并发症将训练集患者分为预后不良组和预后良好组,比较两组患者的临床特征资料。使用最小绝对收缩和选择算子(the least absolute shrinkage and selection operator,LASSO)回归5折交叉验证方法筛选训练集临床和影像组学特征,得到最优特征子集。使用机器学习算法构建预测模型,并使用受试者工作特征(receiver operating characteristics,ROC)曲线评价各模型对肝血管瘤术后疗效的预测价值。结果 训练集中预后良好64例,预后不良28例,两组在慢性疾病、肝血管瘤最大径、血管瘤数、血管瘤供血动脉支数、肝切除大小、术中出血量方面差异均有统计学意义(P<0.05)。依据LASSO回归中的最佳λ取值筛选出14个非零系数特征构成的最优特征子集,其中包括12个组学特征和2个临床特征。利用训练集筛选出的最优特征子集构建Logistic回归、CatBoost、XGBoost和LightGBM模型的AUC分别为0.820、0.722、0.784、0.693。验证集构建的Logistic回归、CatBoost、XGBoost和LightGBM模型的ROC曲线下面积(AUC)分别为0.814、0.706、0.785、0.684。4种机器学习模型的预测效果良好,其中Logistic回归的预测效果优于其他3种。结论 血管瘤最大径和血管瘤数目,结合Gd-EOB-DTPA增强MRI影像组学,以此构建的机器学习模型可用于预测肝血管瘤腹腔镜肝切除术后疗效,其中Logistic回归算法构建的模型更加精准。  相似文献   
3.
Partial unilateral ureteral obstruction in rats   总被引:3,自引:0,他引:3  
This review comprises an overview of the current knowledge on experimental partial unilateral ureteral obstruction (PUUO) and a summary of our latest original experimental PUUO studies in rats. Neonatal PUUO is the type of obstruction that is most often encountered in pediatric clinical practice. However, the pathogenesis of PUUO is still incompletely understood. Most of our knowledge on PUUO has been derived from experimental studies in a variety of animal models. Although progress has been made, the natural history of congenital hydronephrosis is still incompletely described. The effects on kidney functions of long-term urinary tract obstruction, especially PUUO, have been less intensively studied. Recently, we created models with mild and severe PUUO in young rats by embedding the upper one fourth or the upper two thirds of the left ureter into the psoas muscle, respectively. Thereafter, the technique was used to create mild and severe PUUO in newborn rats and magnetic resonance imaging studies showed that both mild and severe obstruction caused a time-dependent decrease in renal blood flow. Compensatory increase in total kidney volume and renal vein blood flow in contralateral non-obstructed kidneys was not detectable when functional deterioration in the partially obstructed kidneys was present. Finally, we investigated the dynamic changes in renal relative signal intensity (RSI) of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) using magnetic resonance imaging in rats with partial, complete unilateral ureteral obstruction and sham-operated controls. The results showed that changes in Gd-DTPA RSI are compatible with the known physiological and anatomical changes in kidneys in response to ureteral obstruction and useful for distinguishing an obstructed from a non-obstructed collecting system and also for differentiating a partially obstructed from a completely obstructed collecting system.  相似文献   
4.
Inhalation of calcium trisodium diethylenetriaminepentaacetate (Ca-DTPA) increases the removal of plutonium and other transuranics from the body. Data are required to determine possible biological effects from inhaled DTPA. p]Female rats were given a single or 12 daily, 2–4-h, inhalation exposures to aerosols of 10, 20 and 40% Ca-DTPA and the lungs were examined at 21 and 42 days following the last exposure. No pulmonary pathology was found from the single inhalation treatment with Ca-DTPA while only a slight, peripheral, histiocytosis was observed in the lungs of multiple-treated rats. There was no significant effect of DTPA treatments on body weight, lung weight, hematology or serum chemistry values.  相似文献   
5.
A retrospective study of 50 patients with ethylenediamine allergy revealed that 2 topical products containing ethylenediamine as a stabiliser are the main sources of sensitization in Italy. Some of these patients cross-reacted to piperazine and diethylenetriamine, but none to ethylenediamine tetracetic acid.  相似文献   
6.
张伟  蔡亮  陈跃  黄占文  尹平 《山东医药》2010,50(23):17-19
目的 合成单光子断层扫描(SPECT)/MRI双模式分子探针,并观察其用于肿瘤检测的价值.方法 根据文献方法合成二乙三胺五乙酸-脱氧葡萄糖(DTPA-DG),并将其与氧化钆(Gd2O3)螯合制得Gd-DTPA-DG,进而以99mTc标记获得99mTc-Gd-DTPA-DG.分别以3种放射性活度的99mTc-DTPA-Gd-DTPA-DG、99mTc-DTPA及18F-脱氧葡萄糖(18F-FDG)处理宫颈癌Hela细胞,2 h后消化收集细胞、用γ计数法测量细胞摄取率.结果 宫颈癌Hela细胞对99mTc-Gd-DTPA-DG的摄取率与18F-FDG在3.7 MBq/L时无显著差异(P=0.66),99mTc-Gd-DTPA-DG各活度间细胞摄取率均明显高于99mTc-DTPA(P〈0.01).结论 本研究成功合成99mTc-Gd-DTPA-DG,其结构类似18F-FDG,99mTc-Gd-DTPA-DG可能成为一种同时在磁共振及核医学显像的双模式分子探针,并在提高恶性肿瘤检出率方面发挥重要作用.  相似文献   
7.
Zhu XF  Liu YH  Ye Y 《药学学报》2012,47(3):380-384
为了得到具有核酸切割功能的人工核酸酶, 设计合成了二乙烯三胺单齿、双齿、四齿配体, 目标化合物的结构经红外、核磁氢谱、碳谱和电喷雾质谱确认。在磷酸氢钠-磷酸二氢钠缓冲溶液中对质粒DNA切割活性的初步实验结果表明: 在多齿配体的锌 (II) 配合物存在下, 37 ℃保温48 h后, 质粒DNA由Form I断裂为Form II, 即合成的目标化合物有明显的切割活性。通过T4连接酶实验证明了目标化合物对DNA的切割为水解切割机制。  相似文献   
8.
The effect of two polyamino-polycarboxylic acids, N-(2-hydroxyethyl) ethylenediamine triacetic acid (HEDTA) and diethylenetriamine penta-acetic acid (DTPA) and two thiol-chelating agents, sodium diethyldithiocarbamate (DDC). and dimercaptosuccinic acid (DMS) on the excretion of manganese (Mn) in rabbits given Mn i.p. was studied in order to investigate the affinity of this metal to N,O and S-containing compounds. HEDTA and DTPA were effective, and DDC and DMS were ineffective, in enhancing urinary and faecal excretions of Mn, indicating a greater binding capacity of Mn with chelators having N and O, than with those having S as electron donating centres.  相似文献   
9.
  1. The ability of three putative polyamine antagonists to antagonize behavioural changes induced by spermine was assessed.
  2. Injection of an excitotoxic dose of spermine (100 μg, i.c.v.) in mice results in the development of a characteristic behavioural profile, which has two temporally distinct phases. The early events include clonic convulsions, and the later, more general excitation, includes tremor and culminates in the development of a fatal tonic convulsion.
  3. Co-administration of arcaine (25 μg, i.c.v.) potentiated the early phase effects after spermine injection, but antagonized the development of spermine-induced tonic convulsions. A larger dose of arcaine (50 μg, i.c.v.) given alone resulted in the development of spermine-like body tremor and convulsions. It therefore appears that arcaine is not a pure polyamine antagonist in vivo, but may be a partial agonist.
  4. Similarly, 1,10-diaminodecane appeared to act as a partial agonist in vivo, although it was less potent than arcaine.
  5. In contrast, diethylenetriamine (DET) effectively inhibited the development of the early effects of spermine, but was ineffective against the spermine-induced CNS excitation and tonic convulsions.
  6. It is concluded that none of the putative polyamine antagonists tested behaved as effective polyamine antagonists in vivo, although each produced some antagonism.
  相似文献   
10.
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