目的:探讨3.0T动态增强MRI半定量信号强度-时间(signal intensity-time,SI-Time)曲线及全定量灌注参数在子宫病变中的应用价值。方法:回顾性分析经病理证实为子宫恶性肿瘤20例,良性肿瘤或肿瘤样病变22例。均行3.0T动态增强MRI扫描,并使用Siemens Tissue 4D软件进行图像后处理,勾画感兴趣区并绘制SI-Time曲线。进一步测得感兴趣区的容积定量灌注参数值:容量转移常数(Ktrans)、速率常数(Kep)、血管外细胞外间隙容积比(Ve)。对良、恶性病变组的SI-Time曲线类型进行统计学分析,对良、恶性病变组的定量灌注参数值进行单因素方差分析,多个样本均数的两两比较。结果:20例恶性肿瘤中宫颈癌12例,内膜癌8例;22例良性病变中13例为平滑肌瘤,3例为子宫内膜息肉,3例内膜增生,3例为子宫腺肌症。良性组以I型曲线(59.1%)为主;恶性组以II型曲线(65.0%)为主。不同类型的SI-Time曲线在良恶性病变之间差异具有统计学意义(P=0.011)。若以I型曲线作为诊断子宫良性病变的标准,II和III型曲线作为诊断子宫恶性病变的标准,则诊断灵敏度为90%,特异性为59.1%,阳性预测值为66.7%,阴性预测值为86.7%。恶性病变组Ve值比良性病变组[(0.477±0.143) vs (0.589±0.176),P=0.004]和对照组[(0.477±0.143) vs (0.614±0.146),P=0.004]均低;恶性病变组Ktrans值比对照组低[(0.178±0.067)min−1 vs (0.263±0.111)min−1,P=0.003];良性病变组Ktrans比对照组低[(0.182±0.096)min−1 vs (0.263±0.111)min−1,P=0.011]。结论:动态增强MRI半定量SI-Time曲线及全定量灌注参数值在子宫良恶性病变鉴别诊断中具有积极意义,可作为常规MRI形态学诊断的有效补充手段。 相似文献
Introduction: Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS of a putative autoimmune origin characterized by neurologic dysfunction disseminated in space and time due to demyelination and axonal loss that results in progressive disability. Recent advances in understanding the immune pathogenesis of the disease resulted in the introduction of numerous effective immunomodulatoty drugs having diverse mechanisms of action, modes of administration and risk–benefit profiles. This results in more complex albeit more promising treatment selection and choices.
Areas covered: The epidemiology, clinical features, pathogenesis and diagnosis of the disease are discussed. The mode of action and main characteristics of current immunomodulatory drugs for MS and their place in the therapeutic algorithm of the disease based on evidence from clinical trials are described. Speculation on new paradigms, treatment goals and outcome measures aimed at improving the landscape of MS treatment is presented.
Expert opinion: Multiple disease, drug and patient-related factors should be taken into consideration when selecting the appropriate drug and treatment strategy to the appropriate patient, thus paving the road for personalized medicine in MS. 相似文献
The present work objective was to prepare and to observe the effect of ethylene glycol dimethacrylate on swelling and on drug release behavior of pH-sensitive acrylic acid–polyvinyl alcohol hydrogel.
Methods
In the present work, pH sensitive acrylic acid–polyvinyl alcohol hydrogels have been prepared by free radical polymerization technique in the presence of benzoyl peroxide as an initiator. Different crosslinker contents were used to observe its effect on swelling and on drug release. Dynamic and equilibrium swelling studies of prepared hydrogels were investigated in USP phosphate buffer solutions of pH 1.2, 5.5, 6.5 and 7.5 with constant ionic strengths. Hydrogels were evaluated for polymer volume fraction, solvent interaction parameter, molecular weight between crosslinks, number of links per polymer chain, diffusion coefficient, sol–gel fraction and porosity. To demonstrate the release pattern of the drug, zero-order, first-order, higuchi and korsmeyer-peppas models were applied. Quality and consistency of hydrogels was examined by FTIR and surface morphology of hydrogels was examined by SEM.
Results
Decrease in swelling and in drug release was seen by increasing content of ethylene glycol dimethacrylate. A remarkable high swelling was observed at high pH indicating the potential of this hydrogel for delivery of drugs to intestine. By increasing the concentration of ethylene glycol dimethacrylate, porosity decreased. Order of release was observed first order in all cases and the mechanism was non–fickian diffusion. FTIR confirmed the formation of network. SEM results showed the incorporation of drug.
Conclusion
The prepared hydrogels can be suitably used for targeted drug delivery to the intestine. 相似文献