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91.
Recently it was reported that there is an increase in monoamine oxidase B (MAO-B) activity in post-mortem brains of patients with Alzheimer's disease. It was postulated that this increase in MAO-B activity was due to gliosis associated with neuronal degeneration. The aim of the present investigation was to evaluate the effect on MAO of neuronal degeneration primarily affecting the cholinergic system. The specific cholinergic toxin AF64A (3 and 4.5 nmol) was injected bilaterally into the cerebral ventricles of rats. We then estimated MAO-A, MAO-B, dopamine (DA) uptake rates and choline acetyltransferase (ChAT) activities in hippocampus, striatum and cortex, 1, 2.5 and 4.5 weeks after the injection. Marked long-lasting reduction in ChAT activities appeared only in hippocampus, consistent with previous reports. The MAO-A activity was unchanged as were DA uptake rates. Neither was there any change in MAO-B activity found 1 week after the injection. However, a significant increase in MAO-B activity appeared after 2.5 weeks and persisted after 4.5 weeks in all 3 brain regions investigated. This result is likely to reflect progressive gliosis after cholinergic neuronal degeneration. Previous results have shown an increased MAO-B activity with age and a further accelerated increase in Alzheimer's disease. Experimentally, hemitransection and injection of kainic acid have been shown to cause a similar increase. The present results show that changes in MAO-B activity also reflect degenerative processes in brain mainly affecting the cholinergic system. 相似文献
92.
93.
Fayyaz S. Sutterwala Gary J. Noel Padmini Salgame David M. Mosser 《The Journal of experimental medicine》1998,188(1):217-222
Macrophages can respond to a variety of infectious and/or inflammatory stimuli by secreting an array of proinflammatory cytokines, the overproduction of which can result in shock or even death. In this report, we demonstrate that ligation of macrophage Fcγ receptors (FcγR) can lead to a reversal of macrophage proinflammatory responses by inducing an upregulation of interleukin (IL)-10, with a reciprocal inhibition of IL-12 production. IL-10 upregulation was specific to FcγR ligation, since the ligation of the Mac-1 receptor did not alter IL-10 production. The identification of the specific FcγR subtype responsible for IL-10 upregulation was determined in gene knockout mice. Macrophages from mice lacking the FcR γ chain, which is required for assembly and signaling by FcγRI and FcγRIII, failed to upregulate IL-10 in response to immune complexes. However, mice lacking either the FcγRII or the FcγRIII were fully capable of upregulating IL-10 production, implicating FcγRI in this process. The biological consequences of FcγRI ligation were determined in both in vitro and in vivo models of inflammation and sepsis. In all of the models tested, the ligation of FcγR promoted the production of IL-10 and inhibited the secretion of IL-12. This reciprocal alteration in the pattern of macrophage cytokine production illustrates a potentially important role for FcγR-mediated clearance in suppressing macrophage proinflammatory responses. 相似文献
94.
目的探讨64层螺旋CT血管成像技术对脑血管病的诊断价值。方法回顾性分析160例头颈部CT血管成像检查患者的影像资料。图像后处理采用多平面重组、最大强度投影和容积再现技术。由两名放射科医师共同对原始及重组图像进行分析。结果94例显示异常,其中狭窄梗阻性病变50例,动脉瘤21例,动脉瘤支架术后1例,夹闭术4例,动静脉畸形3例,烟雾病4例,颈内动脉海绵窦瘘4例,静脉窦血栓4例,直窦闭塞伴永存镰状窦1例,大脑大静脉和直窦瘤样扩张1例,永存舌下动脉1例。结论64层螺旋CT血管成像技术对脑血管病的诊断具有肯定价值和明显优势。 相似文献
95.
J Brohult E Fridell L Sundblad 《Clinica chimica acta; international journal of clinical chemistry》1977,76(2):205-211
Gamma-Glutamyltransferase (GT) and isoenzymes of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) have been studied in 282 cases with increased S-ALP and in 18 chronic alcoholics with normal routine liver tests. There was a high degree of correlation between S-GT and the bile (alpha 1) and liver (alpha 2) fractions of S-ALP. Fractionation of alkaline phosphatases sometimes yielded clinical information, which could not be obtained by determinations of S-ALP and S-GT only. The presence of alpha 1-ALP and increased S-GT appeared to be more sensitive indicators of ethanol-induced liver involvement than other liver tests, including LDH-5/LDH-4 ratios. 相似文献
96.
目的 探讨64排128层螺旋CT低剂量扫描技术对于肺结核患者病情监测的应用价值。方法 对我院120例经临床确诊的成人活动性继发性肺结核患者(痰涂片结核杆菌阳性)行64排CT检查,在其他扫描条件一致情况下分别采用常规120 mA及15~40 mA低剂量扫描,采用盲法阅片,记录每次扫描的CT容积剂量指数(CTDIvol)以及剂量长度乘积(DLP),根据有效剂量转换因子(K=0.014)估算每次CT检查所致有效剂量(ED),对比低剂量和常规剂量扫描和薄层重建的特殊影像表现,进行定量测量及差异分析。结果 两种扫描方式对于实变、支气管扩张、空洞、磨玻璃密度影、钙化灶、树芽征、结节、胸膜肥厚、胸水等结核基本征象显示无明显差异,低剂量扫描受检者所受的X射线辐射剂量显著下降。结论 飞利浦64排螺旋CT低剂量扫描技术和常规剂量相比,在保障检测效果的情况下,辐射剂量大幅度下降,可应用于肺结核的临床诊断及随访。 相似文献
97.
Cademartiri F Maffei E Palumbo A Mollet NR van der Lugt A Crisi G 《The international journal of cardiovascular imaging》2007,23(3):393-396
We present a case of a 78-year-old male referred presented to our institution with amaurosis fugax after walking 20 steps
(“visual claudicatio”). Duplex ultrasound was not able to visualize the carotid arteries. Multislice computed tomography (Sensation
64 Cardiac, Siemens, Germany) of the cerebro-vascular circulation was performed from its origin at the level of the aortic
arch to the circle of Willis. The investigation demonstrated a complete occlusion of both common carotid arteries at their
origin and a severe origo stenosis of both vertebral arteries. An important collateral circulation of the vertebral arteries
through the minor vessels of the neck was also displayed. Both comunicans posterior arteries were small but patent. The intra-cranial
arteries were patent. Multislice CT of the cerebro-vascular circulation is an optimal tool for a comprehensive evaluation
when duplex ultrasound fails.
Electronic Supplementary Material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
98.
农贤刚 《国际检验医学杂志》2016,(22)
目的探讨中性粒细胞CD64与降钙素原(PCT)对骨折患者术后感染早期诊断的临床价值。方法选取2012年5月至2015年5月开放性骨折并实施手术治疗患者80例,将其分为感染组(37例)和未感染组(43例),2组均于术后1、3、5、7d采集静脉血检测CD64和PCT水平,评价2种指标在骨折术后感染诊断中的敏感性及特异性。结果术后1d,感染组CD64显著高于未感染组,差异有统计学意义(P0.05),与未感染组比较,PCT水平差异无统计学意义(P0.05);感染组CD64和PCT水平在术后3d达到高峰,术后3、5、7d水平均显著高于未感染组,差异有统计学意义(P0.05);CD64诊断敏感性及特异性均高于PCT。结论 CD64和PCT测定均有助于骨折术后感染的早期诊断。 相似文献
99.
Xian Ji Jin Joon Mee Kim Hyung Kil Kim Lucia Kim Suk Jin Choi In Suh Park Jee Young Han Young Chae Chu Ju Young Song Kye Sook Kwon Eun Joo Kim 《World journal of gastroenterology : WJG》2010,16(20):2496-2503
AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies. Microscopic features of ITB and CD were reviewed, and eight pathologic parameters were evaluated. Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test, respectively. PCR assays were done using two commercial kits: kit detected IS6110 and MPB64, and kit detected IS6110 only; a manual in-house PCR method was also performed on formalin-fixed, paraffin-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000), giant cells (P = 0.015), caseation necrosis (P = 0.003), confluent granulomas (P = 0.001), discrete granulomas (P = 0.000), and granulomas with lymphoid cuffs (P = 0.037). However, 29 cases (52.7%) of ITB showed less than five kinds of pathologic parameters, resulting in confusion with CD. The sensitivities and specificities of the TB-PCR test by kit , kit , and the in-house PCR method were 88.9% and 100%, 88.9% and 100%, and 66.7% and 100% in positive and negative controls, respectively. The PCR test done on endoscopic biopsy specimens of ITB and CD were significantly different with kit (P = 0.000) and kit (P = 0.000). The sensitivities and specificities of TB-PCR were 45.5% and 88.1%, 36.4% and 100%, and 5.8% and 100%, for kit and kit and in-house PCR method on endoscopic biopsy specimens. Among the 29 cases of histopathologically confusing CD, 10 cases assayed using kit and 6 cases assayed using kit were TB-PCR positive. A combination of histologic findings and TB-PCR testing led to an increase of diagnostic sensitivity and the increase (from 47.3% to 58.2) was statistically significant with kit (P = 0.000).CONCLUSION: The TB-PCR test combined with histopathologic factors appears to be a helpful technique in formulating the differential diagnosis of ITB and CD in endoscopic biopsy samples. 相似文献
100.
目的比较64层计算机断层摄影扫描冠状动脉成像技术(64-slice computed tomography coronaryangiography,64-SCTCA)和冠状动脉造影(coronary artery angiography,CAG)在冠状动脉粥样硬化性心脏病(冠心病)诊断中的价值。方法回顾性分析126例疑似冠心病的患者64-SCTCA和CAG检查资料,并对两组资料进行对比分析。结果 64-SCTCA和CAG检查结果中可用于评价的病变血管段支数比较,差异无统计学意义(P0.05)。CAG共发现≥50%狭窄节段242个,64-SCTCA共发现≥50%狭窄节段199个,两种检查方法对病变狭窄的显示情况比较,差异无统计学意义(P0.05)。全部126例冠心病患者中有91%通过64-SCTCA发现(110/121)。64-SCTCA诊断冠状动脉病变血管的敏感性、特异性、阳性预测值、阴性预测值分别为81.6%、98.8%、79.5%、99%。结论 64-SCTCA可作为冠心病无创、便捷、可靠的检查方法。 相似文献