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991.
A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children.  相似文献   
992.
目的 研究骨形态发生蛋白-2(BMP-2)复合明胶羟基磷灰石(HA)涂层多孔钛对兔股骨远端骨缺损的修复作用。方法 以多孔钛粉末为原料,制备三维多孔结构钛载体,然后运用碱热处理+模拟体液等化学方法进行HA涂层,制备具有三维空间结构的HA涂层多孔钛复合材料。36只新西兰兔随机分为实验组及对照组,制备股骨远端圆柱状骨缺损模型,实验组植入复合BMP-2的HA涂层多孔钛材料,对照组单纯植入HA涂层多孔钛材料。分别于6、12、24周取材通过组织学和生物力学分析。结果组织学观察显示于各时间点实验组骨生成均不同程度优于对照组;生物力学测试显示在推出实验中所有样品的剪切应力都随时间增长而增大。其中在6周、12周实验组多孔钛在所有时间点均表现出了比对照组高得多的剪切力(P〈0.05),在24周实验组和对照组差异无统计学意义(P〉0.05)。结论 BMP-2复合明胶HA涂层多孔钛较单纯HA涂层多孔钛植入早期具有更良好的生物相容性、骨传导性及骨诱导性,可成功修复兔股骨远端骨缺损。  相似文献   
993.
目的探讨伽玛刀在不适合开放手术或经尿道电切术的高危前列腺增生患者治疗中的应用。方法采用深圳奥沃公司生产的OUR-QGD型立体定向全身伽玛刀治疗20例高危前列腺增生患者。应用国际前列腺症状评分(IPSS)、前列腺重量、最大尿流率(Qmax)、残余尿量作为评价指标。观察上述数据在治疗前后的改变及其临床意义。结果术后随访6个月,IPSS评分由治疗前29分降至19.6分(P<0.01)。前列腺重量平均值均由治疗前的(56.4±4.4)g减少至(54.8±4.3)g(P>0.05)。最大尿流率平均值由治疗前的(6.7±1.8)ml/s增加至(11.5±1.7)ml/s(P<0.01),残余尿量平均值由治疗前的(85.1±27.8)ml降至(50.9±15.6)ml(P<0.01)。结论立体定位体部伽玛刀治疗高危前列腺增生症患者具有简便、安全、无创、痛苦小、并发症少、疗效好,可不需住院等优点,对不愿意接受手术或不宜手术的高危前列腺增生患者不失为一种良好的治疗方法,但费用较高。  相似文献   
994.
Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer.  相似文献   
995.
OBJECTIVE: Recent findings have demonstrated that the EEG possesses long-range temporal (auto-) correlations (LRTC) in the dynamics of broad band oscillations. The analysis of LRTC provides a quantitative index of statistical dependencies in oscillations on different time scales. We analyzed LRTC in resting EEG signals in depressed outpatients and healthy controls. METHODS: The participants in this study were 11 non-depressed, age-matched controls, and 11 unmedicated unipolar depressed patients. EEG data were obtained from each participant during 5-min resting baseline periods with eyes closed and then analyzed with detrended fluctuation analysis (DFA), a scaling analysis method that quantifies a simple parameter to represent the correlation properties of a time series. The scaling exponent, the result of DFA, provides a quantitative measure of LRTC from the EEG. RESULTS: The present study demonstrates that all the scaling exponents in depressed patients and healthy controls were greater than 0.5 and less than 1.0, regardless of condition. Furthermore, the scaling exponents of depressed patients have relatively higher values in whole brain regions compared to healthy controls, with significant differences at F3, C3, T3, T4 and O1 channels (p<0.05). Finally, a significant linear correlation was observed between the severity of depression and the scaling exponent over most of the channels, except O2. CONCLUSIONS: These results suggest that the brain affected by a major depressive disorder shows slower decay of the LRTC, and that the persistence of the LRTC of EEG in depressed patients was associated with the severity of depression over most of the cortical areas. SIGNIFICANCE: The DFA method may broaden our understanding of the psychophysiological basis of depression.  相似文献   
996.
目的研究基于计算机模糊智能识别运算的语言障碍诊治仪ZM2.1(简称:语言障碍ZM2.1)对失语流利性检测的效度与信度。方法采用ABC法和语言障碍ZM2.1两种方法分别对58例失语症患者进行流利性检测,两种方法检测间隔时间在3d之内。结果ABC法流利性内部一致性检验,整体克朗巴赫α系数(Cronbach α)=0.8732;语言障碍ZM2.1平均语速和ABC法流利性总分有正相关性趋势,Spearman系数为0.721(P〈0.01);语言障碍ZM2.1检测流利性的准确度为81%(以XABC法为标准);测得两者流利性结果一致性良好(P〈0.01)。结论语言障碍ZM2.1在评价失语症流利性方面具有良好的信度和效度,可用于临床进行失语症的流利性检测。  相似文献   
997.
目的:通过基因微阵列分析,研究经显微切割后的前列腺上皮内瘤变(PIN)的基因表达谱,并将其与前列腺良性增生(BPH)及前列腺癌的mRNA基因表达谱进行对比,探讨前列腺癌的发生、发展,检测PIN及前列腺癌的肿瘤标志物。方法:采用美国Affymetrix公司的HG-U133A基因芯片,检测了16例人的前列腺组织标本,包括5例良性标本,6例PIN以及5例前列腺癌标本,均为新鲜冰冻组织。为了精确获得上皮细胞基因表达谱,避免周围间质细胞及单核细胞的RNA 对结果的影响,我们采用了激光捕获显微切割技术,分别得到了3组纯的上皮细胞群进行研究。结果:有些基因的表达强度在从良性增生到PIN到癌的转化过程中,呈逐渐改变的趋势,但笔者发现3组间基因表达谱存在非常显著的差异。与BPH及前列腺癌相比,PIN有其独特的基因表达谱。结论:基因表达谱中显著上调及下调的特异性基因,可以将PIN 和BPH及前列腺癌中区分开来;基因微阵列分析也有助于揭示代谢通路及信号转导途径的变化,有利于靶基因治疗。  相似文献   
998.
目的研究高脂肪膳食诱导的胰岛素抵抗(IR)大鼠下丘脑及脂肪组织中增食欲素和瘦素系统的变化,分析其可能的调控因素。方法IR大鼠模型采用高脂肪膳食诱导并经钳夹技术证实;应用RT-PCR技术检测增食欲素及其受体(OX1R、OX2R)和瘦素受体(LR)以及脂肪组织中瘦素基因mRNA的表达;采用生化比色法测定血清游离脂肪酸(FFA)、放射免疫法测定血清肿瘤坏死因子α(TNF-α)。结果钳夹技术中葡萄糖输注率明显低于对照组;高脂肪膳食诱导的IR大鼠下丘脑中前增食欲素原mRNA的表达较对照组减少约80%(P<0.01);OX1R、OX2R分别增加3.4及3.2倍(P<0.01);瘦素mRNA增加约8倍(P<0.01);LR减少78%;血清FFA和TNF-α均明显高于对照组(P<0.01)。结论高脂肪膳食可诱导大鼠体内IR,并导致增食欲素和瘦素系统平衡状态的破坏;增食欲素和瘦素是机体能量平衡调节网络中的一对重要物质,两者相互作用共同维持机体能量代谢的稳定。血清FFA和TNF-α均可能参与该系统的调控,合理膳食在这一调控中至关重要。  相似文献   
999.
Complications in a donor are a distressing but inevitable occurrence, since graft procurement is a major undertaking. Although the technique for procurement has some similarities to hepatic resection, a donor is very unlike a patient with malignancy. The risk factors identified in these patients cannot be extrapolated to donors. Donor hepatectomy carried out from June 1995 to March 2005 in Chang Gung Memorial Hospital, Kaohsiung Medical Center was reviewed with the aim of identifying risk factors for complications. There were 204 living donor liver transplants, with 205 donor hepatectomies, as 1 living donor liver transplantation was a dual graft. Ten donors (4.88%) suffered complications. There was no difference in terms of age, gender, body weight, operation, and parenchymal time between those who had complications and those who did not. There was also no difference in liver function tests between the 2 groups of donors, but the total bilirubin was significantly higher in donors with complications. The graft weight and remnant liver volume were also similar. The proportion of donors with fatty liver was the same between the 2 groups. The mean blood loss in donors with complications was 170 +/- 79 mL, and that for donors without complications was 95 +/- 77 mL. There was a statistically significant greater blood loss in donors with complications (P < 0.05). The number of segments removed in donors with complications was also higher compared to donors without complications (P < 0.03). Using multivariate analysis, intraoperative blood loss and the number of segments removed were found to be independent risk factors for donor complications. Intraoperative blood loss during graft procurement must be kept low to minimize complications in donors.  相似文献   
1000.
目的 :探讨全肺切除术和经心包内处理血管的全肺切除术治疗肺癌的效果。方法 :对 74例Ⅱb~Ⅲb期肺癌患者行全肺切除术 ,其中 32例在肺癌的全肺切除术中进行了心包内处理血管 ,其余 4 2例行标准全肺切除术。结果 :心包内处理血管组与标准切除组术后各有 1例并发脓胸 ,其中心包内处理血管组的并发脓胸者死亡。术后两组分别随访 2 2例和 31例 ,5年生存率分别为 18.1%和 16 .1%。经心包内处理血管的全肺切除与标准全肺切除术患者 5年生存率和术后并发症发生率差异均无显著性 (P =1.0 0 0和P >0 .0 5 )。结论 :全肺切除术中力争达到根治 ,经心包内处理血管技术的应用 ,对于提高患者的生存率、改善晚期肺癌的生活质量是有价值的  相似文献   
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