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51.
A young man with a left hemifacial hemangioma had during a six months period about forty left hemispheric neurologic attacks suggestive of classic migraine. The neurologic examination was normal during the attack-free period. The CT scan (fig. 1) and the M.R.I. study (fig. 2) only showed a moderate interhemispheric asymmetry. The left internal carotid angiogram showed subtle anomalies of the venous system (fig. 3). All the neurologic manifestations ceased as soon as therapy by aspirin was initiated. A Positron Emission Tomography (PET) study with the oxygen 15 continuous inhalation technique was performed 7 months after the last attack in order to measure the regional Cerebral Blood Flow (rCBF), Oxygen Extraction Fraction (rOEF) and Oxygen Consumption (rCMRO2). Striking, statistically significant, alterations were observed in the left temporo-parieto-occipital area (fig. 4) consisting of a "misery perfusion" syndrome (rCBF = 28-38 ml/100 g/mn; rOEF = 0.64-0.80), without alteration in the rCMRO2 (Table). A repeated PET study 12 months later was unchanged. The association of local chronic oligemia and ipsilateral facial hemangioma, ipsilateral cerebral hypotrophy and venous anomalies suggested the diagnosis of atypical leptomeningeal angiomatosis of the Sturge-Weber type. The importance and persistence of the hemodynamic alterations suggest that chronic oligemia and, hence, tissue hypoxia may participate in the pathogenesis of the migraine-like attacks. Moreover, local circulatory stasis with thrombotic events may be implicated, as suggested by the apparent efficacy of aspirin.  相似文献   
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Summary Combined Positron Emission Tomography (PET) and Proton Magnetic Resonance Imaging (MRI) study were performed in six patients with chronic supratentorial stroke to investigate whether remote hypometabolic regions revealed by PET showed any abnormality on MRI. Either regional oxygen consumption (n=4) or glucose utilization (n=2) were measured using PET and the 15O steady state 18FGD technique, respectively. Four patients, with deeply located brain lesions, showed a significant metabolic reduction in the overlying cerebral cortex. In the remaining two patients, affected by a large cortical infarct, there was a significant crossed cerebellar hypometabolism. The MRI weighted by the parameters spin density (), spin lattice (T1) and spin-spin (T2) relaxation times were obtained employing various sequences in the same subjects. In no patient did the MRI show any contrast modification in these hypometabolic remote regions, suggesting that subtle loss of tissue and/or biochemical change do not underlie the reduction in metabolic rate.  相似文献   
53.
癌组织中p16基因甲基化分析   总被引:1,自引:0,他引:1  
目的探讨抑癌基因p16在胃癌组织中是否存在甲基化异常及其与胃癌发生发展的关系.方法对20例胃癌组织及相应正常胃粘膜组织应用甲基敏感酶(HpaII)和甲基非敏感酶(MspI)酶切,结合PCR扩增技术,对p16基因外显子1、外显子2的二核苷酸胞嘧啶特定序列5'-CCGG-3'位点甲基化进行检测.结果20例胃癌组织中,p16基因外显子1、2异常甲基化分别为5例(25%)和9例(45%),正常组织未发现甲基化异常;14例高甲基化标本中,中分化胃癌4例,低分化7例,高分化1例;有2例存在外显子1、2同时甲基化异常,二者均为低分化胃癌,进展期胃癌(Ⅲa、Ⅳ期各1例)中1例呈现泳动易位;外显子2甲基化异常多发生于晚期肿瘤患者(P<0.05).结论p16基因甲基化异常可能会造成基因功能丧失,从而失去对细胞增殖的负性调控作用,导致胃癌发生与进展;外显子2高甲基化与临床进展有关,可能为晚期事件.  相似文献   
54.
ContextMolecular biomarkers aim to address the established limitations of clinicopathologic factors to accurately risk stratify patients with prostate cancer (PCa). Questions remain as to whether sufficient evidence supports adoption of these biomarkers for clinical use.ObjectiveTo perform a systematic review of the available evidence supporting the clinical utility of the Decipher genomic classifier (GC).Evidence acquisitionThe review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed and conference abstracts from January 2010 to June 2020. Evidence was then graded using the criteria of Simon et al (Simon RM, Paik S, Hayes DF. Use of archived specimens in evaluation of prognostic and predictive biomarkers. J Natl Cancer Inst 2009;101:1446–52) and American Urology Association (AUA) criteria.Evidence synthesisIn total, 42 studies and 30 407 patients were included. GC performance data were available for localized, postprostatectomy, nonmetastatic castration-resistant, and metastatic hormone-sensitive PCa as part of retrospective studies (n = 12 141), prospective registries (n = 17 053), and prospective and post hoc randomized trial analyses (n = 1213). In 32 studies (n = 12 600), the GC was independently prognostic for all study endpoints (adverse pathology, biochemical failure, metastasis, and cancer-specific and overall survival) on multivariable analysis and improved the discrimination over standard of care in 24 studies (n = 8543). GC use changed the management in active surveillance (number needed to test [NNT] = 9) and postprostatectomy (NNT = 1.5–4) settings in five studies (n = 4331). Evidence strength was levels 1 and 2 by the Simon criteria for all disease states other than high-risk PCa, and grades A and B by AUA criteria depending on disease state.ConclusionsConsistent data are now present from diverse levels of evidence, which when viewed together, have demonstrated clinical utility of the GC in PCa. The utility of the GC is strongest for intermediate-risk PCa and postprostatectomy decision-making.Patient summaryIn this paper, we review the evidence of the Decipher genomic classification tool for men with prostate cancer. We found consistent evidence that the test helps identify which cancers are more or less aggressive, which in turn aids in personalized treatment decision-making.  相似文献   
55.
Lasers in Medical Science - Long-pulsed 1064-nm (LP1064) and 755-nm (LP755) lasers have been demonstrated as effective treatments for leg veins. However, few studies of these treatments on Asian...  相似文献   
56.
57.
目的:观察脑泰通组方对局灶性脑缺血再灌注大鼠模型的影响及保护机制。方法:构建局灶性脑缺血再灌注大鼠模型,成模后随机分为模型对照组、阳性药物组、中药组、联合用药组,另选取健康斯泼累格·多雷(SD)大鼠作为假手术组。观察并评估各组大鼠的美国国立卫生研究院卒中量表(NIHSS)评分、脑组织含水量、脑梗死体积百分比,免疫组织化学法检测脑组织Bcl-2相关X蛋白(Bax)、B细胞淋巴瘤-2(Bcl-2)的平均光密度值,蛋白质免疫印迹法、实时定量PCR(QT-PCR)检测脑组织叉头框转录因子3a(FoxO3a)基因、低氧诱导因子-1α(HIF-1α)、核因子κB(NF-κB)、脑源性神经营养因子(BDNF)蛋白及mRNA的表达水平。结果:与假手术组比较,模型对照组NIHSS评分,脑组织含水量,脑组织缺血体积百分比,脑组织FoxO3a、HIF-1α、NF-κB、BDNF蛋白和mRNA的表达水平,Bax、Bcl-2平均光密度值以及Bax/Bcl-2值均显著升高(均P<0.05);与模型对照组比较,药物干预各组的NIHSS评分、脑组织含水量、脑梗死体积百分比、Bax平均光密度值、Bax/Bcl-2值、脑组织NF-κB蛋白和mRNA的表达水平显著降低(均P<0.05),其中联合用药组的降低程度最大(均P<0.05),Bcl-2平均光密度值,脑组织FoxO3a、HIF-1α、BDNF蛋白和mRNA的表达水平显著升高(均P<0.05),其中联合用药组的升高程度最大(均P<0.05)。结论:脑泰通组方能有效保护局灶性脑缺血再灌注大鼠模型脑组织损伤,改善局部脑缺血,其作用机制可能与脑泰通组方调控FoxO3a/HIF-1α/NF-κB信号通路相关。  相似文献   
58.
Huerta  S.  Tran  N.  Yi  B.  Pham  T. 《Hernia》2021,25(5):1289-1294
Hernia - The optimal approach for inguinal hernia repair in the obese remains elusive. Minimally invasive techniques show equivocal results compared to the open method. None of the current analyses...  相似文献   
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Background: Skeletal muscle lacerations are a relatively common injury. Compared with nonrepaired lacerations, surgically repaired muscle lacerations regenerate faster, develop less scar tissue, have a higher return to baseline strength, and have lower incidence of hematomas. Despite the benefits of repair, the optimal repair technique is still unknown. The purpose of this study was to examine the biomechanical properties of common muscle repair techniques to determine the optimal repair. Methods: Forty-two fusiform porcine muscle specimens were dissected and used for this study. Three suture techniques were used for comparative analysis: Figure-eight, Mason Allen, and Perimeter. Each muscle was transected and then repaired using one of the 3 techniques. Fourteen muscle-tendon specimens were prepared for each group and tested for tensile failure using a material testing system. Biomechanical properties, including peak failure point and stiffness, were compared for differences between the suture groups by 1-way analysis of variance. The average time per repair technique was also recorded. Results: The Perimeter technique showed a statistically significant higher peak failure point than the Mason Allen technique (P = .03). Both the Figure-eight (P = .047) and Perimeter techniques (P < .001) were significantly stiffer than the Mason Allen technique. The repair time was comparable across all 3 techniques. Conclusions: The Figure-eight and Perimeter repairs were found to be similar in peak failure point and stiffness, whereas the Mason Allen technique showed significantly lower stiffness and peak failure point. The Figure-eight was the quickest repair to perform. The Figure-eight technique may be strongly considered for muscle laceration repairs due to its simplicity and efficiency.  相似文献   
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