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在介绍肿瘤样品代谢物的核磁共振波谱技术的研究方法的基础上,从离体组织和活体组织两个方面综述核磁共振波谱(NMR)在诊断肿瘤方面的应用进展,分析了它在肿瘤诊疗中的应用前景。在离体组织方面,人们通过1H和31P-NMR谱观测病人的体液样品、培养的细胞、切除的组织等来研究脂质、磷脂等代谢物的分布,观测肿瘤与对照组织之间的差别。其中利用组织提取物的方法能够得到分辨率较高的图谱,非常适合应用于肿瘤诊断和治疗方法的研究。高分辨魔角旋转(HR-MAS)的方法在肿瘤诊断研究方面展现出新的生命力,利用高分辨魔角旋转技术可以直接得到组织细胞中很多分子水平的代谢物结构和组成信息,因此它在癌症的早期诊断中具有很好的前景。在活体核磁共振波谱诊断肿瘤方面,主要应用1H和31P核磁共振波谱,结合MRI为非侵入性肿瘤分析提供了一种临床可用的方法。MRI与MRS技术的结合将使核磁共振波谱在医学领域有更大的应用空间。 相似文献
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核磁共振技术在生物组织中的应用 总被引:11,自引:3,他引:8
在生物组织内部存在大量的生化、生理反应以及分子的扩散运动,它们相互独立, 又相互关联,共同构成一个生化反应网络. 在病理条件下,某些生化反应过程会发生改变,代谢中间体可能会出现质和量的变化. 核磁共振 (NMR)可以对这些过程的研究提供非常有用的信息. 目前,有3种核磁共振波谱技术可以用于生物组织的研究:① 活体组织定域波谱技术;② 生物组织提取物的液体高分辨核磁共振技术;③ 离体组织的高分辨魔角旋转技术. 这些方法各有优劣,互为补充. 介绍了在生物组织的NMR研究方面的最新进展. 相似文献
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测量质子化学位移各向异性(CSA)有助于表征分子结构与其动力学,但由于1H-1H同核偶极耦合相互作用很强及质子各向异性化学位移较小,测量质子化学位移各向异性仍具有巨大挑战,特别是对含有多种质子的生物大分子,如蛋白质.本文简要综述了测量质子化学位移各向异性的方法,包括同核去耦慢速魔角旋转方法、超快魔角旋转方法、对称重耦(RNnv)方法、xCSA方法以及量子化学计算方法.我们重点介绍了在高速魔角旋转条件下蛋白质氨基质子化学位移各向异性的测量及它们与氢键长度、蛋白质二级结构之间的关系. 相似文献
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代谢组学方法分析鸡胚胎发育过程中脑代谢物 总被引:2,自引:0,他引:2
本文应用高分辨魔角旋转核磁共振(HR-MAS NMR)方法对发育过程中(孵化12天至出壳后1天)鸡胚胎大脑、小脑和视叶3种脑组织中的代谢物含量进行了测定,并利用模式识别方法对整体代谢特征进行了归类分析. 结果表明:胚胎发育过程中不同脑区的代谢物组成存在差异,可能与这些脑区的功能及发育特征等的不同有关. 在NMR方法检测到的多种小分子代谢物中,γ-氨基丁酸、N-乙酰天冬氨酸、牛磺酸、肌醇以及胆碱等在鸡胚胎脑组织中的分布有区域性差异,这些差异也是区分大脑、小脑和视叶组织的特征性代谢物. 相似文献
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癌变与正常直肠组织的核磁共振氢谱差异的研究 总被引:3,自引:3,他引:0
核磁共振(NMR)波谱法是一种表征分子结构、组成变化的有效手段,能够得到生物组织中的核酸、蛋白质、脂类和糖类等生物大分子的含量、分子的空间排列和结构特征等信息,可以从分子水平上研究肿瘤与对照组织之间的差别,更深入地揭示肿瘤的发生、发展中产生的各种分子水平变化。文章对9例直肠癌组织及癌旁正常组织进行了核磁共振氢谱的测定。结果表明,直肠正常和癌变组织的核磁共振氢谱存在显著的差异,这可以通过对谱图特征峰区域积分面积相对比值的差别看出来。直肠正常组织核磁共振氢谱中A0.9/A3.0,A1.3/A3.0,A2.0/A3.0,A1.3/A0.9及A4.1/A3.0值较相应的癌组织偏大,直肠癌组织核磁共振氢谱中A3.2/A3.0值较相应正常直肠组织偏大。通过这些差异核磁共振氢谱技术有可能发展成为早期诊断直肠癌组织的一种方法。 相似文献
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文章对6例直肠癌变及正常组织进行高分辨魔角旋转核磁共振波谱研究,结果显示直肠癌变和正常组织的核磁共振氢谱存在明显差异。这可以通过特征峰面积与0.88处峰积分面积的比值上的差异看出:(1)在化学位移0.75~1.55之间,癌组织各种氨基酸[缬氨酸,异亮氨酸,亮氨酸]与脂肪酸甲基的比值(I2/I1),癌组织乳酸盐与脂肪酸甲基的比值(I4/I1)都明显增大。(2)在化学位移1.55~2.90之间,癌变组织中亮氨酸、赖氨酸、异亮氨酸与脂肪酸甲基的比值(I7/I1), 谷氨酸、谷氨酰胺、缬氨酸、琥珀酸与脂肪酸甲基的比值((I9+I11)/I1)、天冬氨酸与脂肪酸甲基的比值((I12+I14)/I1)都较正常组织明显增大。(3)在化学位移2.90~3.49之间,癌变组织氨基酸与脂肪酸甲基的比值(I15/I1)、胆碱类与脂肪酸甲基的比值((I16+I17)/I1)、牛磺酸与脂肪酸甲基的比值((I18+I19)/I1)都较正常组织明显增大。(4)在化学位移3.49~4.50之间,其他代谢物与脂肪酸甲基的比值(I20/I1),以及甘油基与脂肪酸甲基的比值(I22/I1)在癌变组织中都有增大的趋势。(5)化学位移4.5~10之间,癌变组织的核苷酸发生了变化,癌变组织的不饱和脂肪酸与脂肪酸甲基的比值(I24/I1)明显减小。(6)在化学位移-8~0.75之间,癌变组织的谱峰有减少的趋势。通过上述分析可知,通过癌变与正常组织代谢物NMR谱峰的差异,可以区分癌变和正常组织。说明核磁共振波谱技术可能发展成为一种诊断直肠癌的新方法。 相似文献
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颞叶结构参与了多种中枢退行性疾病的发生和发展. 了解生理状态下大鼠的这些脑区的代谢特征可以为动物模型的病理研究提供基础数据和参考. 本文采用高分辨魔角旋转核磁共振(HR-MAS NMR)波谱技术和主成分分析(PCA)方法对S.D.大鼠双侧颞叶、海马和内嗅皮质的代谢物进行了分析,结果发现这3个脑区的代谢表征存在显著差异. 颞叶区的N-乙酰天门冬氨酸和牛磺酸的浓度最高,肌醇和肌酸的浓度最低;海马区的甘氨酸和胆碱的浓度最高;而在内嗅皮质区则是谷氨酰氨的浓度最高. 另外,还证实了HR-MAS NMR-PCA技术是研究生理和病理状态下脑组织各亚结构代谢表征的一种有效的手段. 相似文献
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生物医学核磁共振中的模式识别方法 总被引:8,自引:6,他引:2
模式识别(PR)是把具体事物进行正确归类的科学,它能解决许多对复杂体系的认识问题. 生物医学核磁共振波谱(NMR)的理解和分析便是其中一种. 在受到病理或者其他刺激后,生物体内的代谢物水平会发生变化,这种变化可以通过液体高分辨核磁共振的手段来观察. 模式识别把这种认识进一步深化,不仅可以将正常状态与病理状态区分开,还能找到是哪些生化指纹导致两种状态的差异,为生理、病理和药理等研究,以及临床诊断提供依据. 模式识别与生物核磁共振波谱的结合,已经发展成为代谢组学研究的关键技术,甚至被称为基于核磁共振的代谢组学. 主要讨论适用于生物医学核磁共振中的模式识别方法及其最新进展. 相似文献
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So Yeon Kim Siwon Kim Chul-Woong Woo Jae Ho Byun Seung Soo Lee Moon-Gyu Lee Haeryoung Kim Kyoung Ho Lee Young Hoon Kim Jai Young Cho Suhkmann Kim Jin Seong Lee 《Applied magnetic resonance》2014,45(1):19-35
To explore the potential of high-resolution magic angle spinning (HRMAS) 1H nuclear magnetic resonance (NMR) spectroscopy for differentiation and metabolite characterization of hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM), we prospectively included 21 pathologically confirmed malignant hepatic tumors (8 HCC and 13 CRLM) and 26 non-tumorous hepatic parenchyma from 26 patients who underwent hepatic tumor resection. Using intact tissue samples obtained during surgery, HRMAS 1H NMR spectroscopy was performed at 11.7 T. All observable metabolite signals were acquired using a water-presaturated standard one-dimensional Carr–Purcell–Meiboom–Gill sequence. Metabolomic profiles contributing to the differentiation of HCC and CRLM and of each tumor and non-tumorous hepatic parenchyma were represented by orthogonal partial least squares discriminant analysis (OPLS-DA) and loading plots. Metabolite intensity normalized by total spectral intensities in both tumors was compared using student’s t tests. OPLS-DA and loading plots demonstrated good separation between tumors and non-tumorous hepatic parenchyma. The metabolomic characteristics of HCC showed separation from those of CRLMs according to OPLS-DA. Compared with CRLM, HCC showed significantly elevated levels of glucose (P < 0.01) and sn-Glycero-3-phosphocholine (P < 0.01), and decreased levels of hypoxanthine (P = 0.04). HCC and CRLM could be differentiated by the metabolic profile using HRMAS 1H NMR spectroscopy. 相似文献
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提出了计算苯甲醛亚胺、N-苯基亚胺、N-甲基亚胺、N-异丙基亚胺中亚胺基氮原子15N NMR化学位移的经验公式:δcal=δ0n+Δα+Δβ+Δγ+c. 按亚胺基氮原子和碳原子上两类取代基的不同分别结合最小二乘法通过线性回归各得到5种取代基参数,计算结果分别以其化学位移数据为样本点作回归检验,置信度为99.5%,最大误差Δδ≤3.1,大约有95%的15N NMR化学位移计算值的计算误差小于3.0(相对误差小于0.3%). 初步分析了芳香族亚胺苯环上对位取代基对亚胺基氮原子化学位移的影响. 相似文献
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Shimizu A Ito K Sasaki K Hayashida M Tanabe M Shimizu K Matsunaga N 《Magnetic resonance imaging》2007,25(10):1430-1436
PURPOSE: The aim of this study was to evaluate the frequency and magnetic resonance imaging (MRI) features of clinically benign, small (<2 cm) hyperintense hepatic lesions in the cirrhotic liver on T1-weighted MR images seen at serial MRI. MATERIALS AND METHODS: This study included 189 patients with cirrhosis, who underwent hepatic MRI more than twice with an interval of at least 12 months. The initial MR images were reviewed for the presence of small hyperintense lesions on T1-weighted images. The size, location and signal intensity on T2-weighted images as well as enhancement patterns of the corresponding lesions were recorded. RESULTS: On the initial T1-weighted MR images, 43 small hyperintense hepatic lesions were detected in 23 (12%) of 189 patients. Twelve (28%) of 43 lesions showed early enhancement and were pathologically diagnosed as hepatocellular carcinoma (HCC) during the follow-up period. Thirty-one (72%) of 43 lesions showed no early enhancement with various signal intensity on T2-weighted images (hyperintensity=4, isointensity=20, hypointensity=7). Among these 31 lesions, 12 showed no interval change, while 11 disappeared (n=10) or decreased in size (n=1). In the remaining eight lesions, seven were diagnosed as HCC on the basis of pathologic confirmation or the interval growth. CONCLUSION: Small hyperintense hepatic lesions on T1-weighted magnetic resonance (MR) images without early enhancement on the arterial-phase contrast-enhanced dynamic studies in patients with cirrhosis usually showed no interval growth or disappeared during the serial MRI. These lesions with additional findings of iso- or hypointensity on the T2-weighted MR images without "washout effect" on the contrast-enhanced equilibrium-phase images may more frequently be clinically benign or hyperplastic nodules than HCCs. 相似文献
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Seung Up Kim Young Chul Kim Ji Soo Choi Kyung Sik Kim Gi Hong Choi Jin Sub Choi Jun Yong Park Do Young Kim Sang Hoon Ahn Eun Hee Choi Young Nyun Park Chae Yoon Chon Kwang-Hyub Han Myeong-Jin Kim 《Magnetic resonance imaging》2010
Liver fibrosis determines the functional liver reserve. Several studies have reported that the apparent diffusion coefficient (ADC) values of diffusion-weighted magnetic resonance imaging (DW-MRI) can assess liver fibrosis. We investigated whether DW-MRI predicts postoperative hepatic insufficiency and liver fibrosis in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Twenty-six patients with HBV-related HCC who received preoperative DW-MRI on a 3-T MRI system were enrolled between July and December 2008. ADC values were measured twice by two observers. Three “b values” were used: 50, 400 and 800 s/mm2. Postoperative hepatic insufficiency was defined as persistent hyperbilirubinemia (total bilirubin level >5 mg/dl for more than 5 days after surgery) or postoperative death without other causes. The mean age (21 men and 5 women) was 51.4 years. Three patients experienced postoperative hepatic insufficiency. liver stiffness measurement predicted postoperative hepatic insufficiency, advanced fibrosis (F3–4), and cirrhosis significantly [area under the receiving operator characteristic curve (AUROC)=0.942, 0.771 and 0.818, respectively, with P=.047, 0.048 and 0.006, respectively]; ADC values of DW-MRI, however, did not (AUROC=0.797, 0.648 and 0.491, respectively, with P=.100, 0.313 and 0.938, respectively). Reliability of ADC values between right and left hepatic lobes (ρ=0.868 and ρ=0.910 in the first and second measures of Observer A; ρ=0.865 and ρ=0.831 in the first and second measures of Observer B) was high and the intra- and interobserver reliability (ρ=0.958 in observer A and ρ=0.977 in observer B; ρ=0.929 in the first measure and ρ=0.978 in the second measure between the two observers) were high. All reliability was significant (P<.001). Our results suggest that DW-MRI on a 3-T MRI system is not suitable for predicting postoperative hepatic insufficiency, advanced liver fibrosis, and cirrhosis in patients with HBV-related HCC, despite significantly high reliability. 相似文献
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用原子电负性、静电作用、极化度作为基本参数,并结合表征原子空间连接方式的立体效应参数,对醇分子中不同环境碳原子的化学位移进行关联, 将120个模型化合物(91个脂肪一元醇, 29个二元醇)中747个碳原子相关参数值和化学位移值带入模型中得到如下估算方程: δC=42.947 9 + 63.064 0Qi-3.628 6F+5.121 3Σαx-6.584 8QiΣαx -4.842 7NαH-0.585 5NγH-4.104 6NγOH (R=0.998 1 R2=0.996 1 S=1.14 F=27 125.2 n=747) 方程中各参数物理意义比较明确. 通过用“留一法”(LOO)检验(Rcv=0.998 0,R2cv = 0.996 0,Scv=1.16)及对样本外5个化合物69个碳原子化学位移的预测值和实验值比较, 结果表明模型方程具有很好的稳定性和预测精度, 该模型的提出为以后计算更加复杂化合物的13C NMR化学位移奠定了良好的基础. 相似文献