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1.
Anxiety is a normal aspect of human personality, which can manifest in a variety of disorders and other negative traits. The primary treatment for anxiety is the class of drugs known as the selective serotonin reuptake inhibitors (SSRIs), which bind to the serotonin reuptake transporter. The upstream region of the gene that codes for this transporter contains a polymorphism that is an insertion/deletion event that in turn, produces long (l) and short (s) alleles in the population. This particular polymorphism in the serotonin transporter, the 5HTTLPR (serotonin transporter linked polymorphic region), is thought to be involved in the genesis of anxious traits and disorders. Most studies with human subjects have examined adult behavior, which may derive from diverse experiential and environmental backgrounds, as well as genetic differences. To better isolate the effect of genetics, we genotyped 128 infant and juvenile monkeys for the 5HTTLPR and tested for behavioral response in four testing paradigms designed to elicit fearful-anxious behaviors: a free play, remote-controlled car, human intruder, and novel fruit test. The s/s monkeys were found to be behaviorally inhibited in the free play test, engaged in more fear behaviors in the remote-controlled car test, and threatened more in the stare portion of the human intruder test, even though a small number of monkeys were assessed. There was no difference between genotypes of either sex in the prolactin response to fenfluramine. These data indicate greater anxiety in the s/s monkeys for distinct facets of anxious behavior, which are independent of a global neurohormonal challenge test. These neurobehavioral data support recent neuroimaging findings in humans indicating the importance of the 5HTTLPR for amygdala-dependent anxious behavior. 相似文献
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Gianfranco Loi Ph.D. Marco Dominietto Ph.D. Irene Manfredda M.D. Eleonora Mones Ph.D. Alessandro Carriero M.D. Eugenio Inglese M.D. Marco Krengli M.D. Marco Brambilla Ph.D. 《Journal of digital imaging》2008,21(3):329-337
This note describes a method to characterize the performances of image fusion software (Syntegra) with respect to accuracy
and robustness. Computed tomography (CT), magnetic resonance imaging (MRI), and single-photon emission computed tomography
(SPECT) studies were acquired from two phantoms and 10 patients. Image registration was performed independently by two couples
composed of one radiotherapist and one physicist by means of superposition of anatomic landmarks. Each couple performed jointly
and saved the registration. The two solutions were averaged to obtain the gold standard registration. A new set of estimators
was defined to identify translation and rotation errors in the coordinate axes, independently from point position in image
field of view (FOV). Algorithms evaluated were local correlation (LC) for CT-MRI, normalized mutual information (MI) for CT-MRI,
and CT-SPECT registrations. To evaluate accuracy, estimator values were compared to limiting values for the algorithms employed,
both in phantoms and in patients. To evaluate robustness, different alignments between images taken from a sample patient
were produced and registration errors determined. LC algorithm resulted accurate in CT-MRI registrations in phantoms, but
exceeded limiting values in 3 of 10 patients. MI algorithm resulted accurate in CT-MRI and CT-SPECT registrations in phantoms;
limiting values were exceeded in one case in CT-MRI and never reached in CT-SPECT registrations. Thus, the evaluation of robustness
was restricted to the algorithm of MI both for CT-MRI and CT-SPECT registrations. The algorithm of MI proved to be robust:
limiting values were not exceeded with translation perturbations up to 2.5 cm, rotation perturbations up to 10° and roto-translational
perturbation up to 3 cm and 5°. 相似文献
3.
目的 探讨乳腺钼靶摄影和增强磁共振(MRI)在乳腺病变诊断中的应用。方法 回顾性分析2015年9月~2017年5月我院收治的经乳腺钼靶摄影和增强MRI诊断,最终病理确诊的90例乳腺疾病患者,共104个病灶,对比两种诊断技术的诊断价值。结果 104个病灶中良性60例、恶性44例。MRI诊断灵敏度、阴性预测值、符合率高于钼靶,差异有统计学意义(P<0.05)。MRI诊断灵敏度、特异度、阳性预测值、阴性预测值、符合率分别为88.64%、91.67%、88.64%、91.67%、90.38%。恶性病灶粗大不均、多形性、簇状、不均匀强化、增强Ⅲ型比重高于良性病灶,差异有统计学意义(P<0.05)。按照OR比从高到底分别为增强Ⅲ型、多形性、不均匀强化、簇状、粗大不均。恶性病灶ADC低于良性病灶,差异有统计学意义(P<0.05)。结论 MRI诊断乳腺病变的灵敏度、特异度、阳性预测值、阴性预测值、符合率分别高于钼靶,因此增强MRI诊断乳腺病变的效用更好。 相似文献
4.
Hye-Suk Hong Se Hoon Kim Hae-Jeong Park Mi-Suk Park Ki Whang Kim Won Ho Kim Nam Kyu Kim Jae Mun Lee Hyeon Je Cho 《Yonsei medical journal》2013,54(1):123-130
Purpose
To investigate the correlations between parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and prognostic factors in rectal cancer.Materials and Methods
We studied 29 patients with rectal cancer who underwent gadolinium contrast-enhanced, T1-weighted DCE-MRI with a three Tesla scanner prior to surgery. Signal intensity on DCE-MRI was independently measured by two observers to examine reproducibility. A time-signal intensity curve was generated, from which four semiquantitative parameters were calculated: steepest slope (SLP), time to peak (Tp), relative enhancement during a rapid rise (Erise), and maximal enhancement (Emax). Morphologic prognostic factors including T stage, N stage, and histologic grade were identified. Tumor angiogenesis was evaluated in terms of microvessel count (MVC) and microvessel area (MVA) by morphometric study. As molecular factors, the mutation status of the K-ras oncogene and microsatellite instability were assessed. DCE-MRI parameters were correlated with each prognostic factor using bivariate correlation analysis. A p-value of <0.05 was considered significant.Results
Erise was significantly correlated with N stage (r=-0.387 and -0.393, respectively, for two independent data), and Tp was significantly correlated with histologic grade (r=0.466 and 0.489, respectively). MVA was significantly correlated with SLP (r=-0.532 and -0.535, respectively) and Erise (r=-0.511 and -0.446, respectively). MVC was significantly correlated with Emax (r=-0.435 and -0.386, respectively). No significant correlations were found between DCE-MRI parameters and T stage, K-ras mutation, or microsatellite instability.Conclusion
DCE-MRI may provide useful prognostic information in terms of histologic differentiation and angiogenesis in rectal cancer. 相似文献5.
磁共振扩散加权成像对兔脑缺血再灌注伤的评价 总被引:3,自引:1,他引:2
目的探讨兔脑缺血再灌注后磁共振扩散加权成像(DWI)的特点。方法将成年新西兰兔用线栓法建立兔大脑中动脉闭塞再灌注(MCAO/R)模型,再将成功的兔MCAO/R模型随机分为永久性缺血组和缺血再灌注组;另取同样动物行假手术分别作为缺血组及再灌注组的对照组;观察不同时间DWI像上高信号区范围变化及表观扩散系数(ADC)的演变特点。结果1.缺血组:缺血1h可见到DWI像上明显的高信号伴ADC值的下降,缺血不同时间点DWI像上的高信号区较缺血1h均有增大,24h后趋于稳定。缺血组不同时间点平均ADC值呈先下降后上升的趋势。2.再灌注组:与再灌注前相比,再灌注2h、5h组均表现为DWI像上高信号区缩小及ADC值升高;再灌注11h组表现为高信号范围增大伴ADC值升高;再灌注23h、47h组表现为高信号范围增大而ADC值出现较明显下降。结论急性脑缺血后DWI像高信号区及ADC值的下降经早期再灌注后可明显改善,但持续再灌注可能导致ADC值再次下降。 相似文献
6.
目的:提出一种可以精确计算磁共振扩散张量成像扩散椭球表面积的方法。方法:根据理想扩散椭球是旋转椭球及扩散张量矩阵均正定,可将三轴椭球校正为旋转椭球,进而由A.M.Legendre公式推出计算扩散椭球表面积的简化公式。分别利用A.M.Legendre、Knud Thomsen及本文提出的方法计算四种扩散椭球的表面积以评价本文方法的可行性。结果:对于旋转椭球,本文所提方法的计算结果与A.M.Legendre方法的结果一致。结论:本文所提方法计算量较小,可以精确地计算扩散椭球表面积。 相似文献
7.
目的 探讨131I SPECT/CT断层融合显像在评价分化型甲状腺癌(DTC)骨转移中的价值.方法 30例确诊为骨转移的DTC患者纳入本研究,其中男14例,女16例,平均年龄54.3±12.6岁.在口服治疗剂量131I后的80~ 96小时完成131I全身平面显像和SPECT/CT断层融合显像.结果 30例患者中单发性骨转移8例,多发性骨转移22例.单发性骨转移的病灶分别位于胸骨、颈椎、胸椎、股骨、锁骨、颅骨和肋骨.22例多发骨转移患者的病灶主要位于脊柱、肋骨、胸骨和骨盆骨等.所有患者的SPECT/CT图像上均可见131I异常放射性浓聚,同机CT示24例为骨破坏,1例为成骨性改变,CT结果为阴性者5例.多发骨转移组的血清甲状腺球蛋白(Tg)明显高于单发骨转移组(P=0.018),两组血清甲状腺球蛋白抗体(A-Tg)并无明显差别(P=0.212).结论 131I SPECT/CT断层融合显像可以较好的将代谢信息和解剖结构信息相结合,更好的评价DTC患者的骨转移. 相似文献
8.
据世界卫生组织预测,到2030年抑郁症将会上升至世界疾病负担首位,到2040年抑郁症将是导致残疾的最常见的原因。研究表明,最多只有30%~40%的抑郁症患者在任何治疗中都会有缓解,目前抑郁症的治疗仍以经验性治疗为主,尚无临床实践中可用的生物标记物用于患者的个体化治疗。研究表明脑磁共振成像具有预测抗抑郁治疗后临床改善的潜在价值,本文主要从抑郁症的脑结构MRI和功能MRI两个方面综述抑郁症治疗前脑MRI改变与抗抑郁治疗临床改善间关系的研究。 相似文献
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目的:基于核磁共振下高分辨率结构成像及功能扫描评价老年抑郁症患者的脑功能及结构。方法:选取2015年1月至2016年7月于我院就诊的抑郁症老年患者50例为研究组,招募50例老年健康者为对照组,所有入组者均进行核磁共振下高分辨率结构像及功能扫描,采用MRIcro软件转化,应用REST、SPM 8软件进行图像结果分析。结果:抑郁组的汉密尔顿抑郁量表(HAMD)评分为(26.7±1.6)分,对照组为(4.7±1.7)分,两组比较差异具有统计学意义(t=66.636,P0.001)。抑郁组患者中左侧的梭状回、颞上回、楔前叶、顶下小叶、中央后回、中央旁小叶,以及右侧的枕中回、顶下小叶、额上回的ReHo较健康组显著减低(P0.05),抑郁组患者的左侧颞下回、额下回、楔前叶,右侧内侧扣带回、梭状回、颞下回、楔叶的GMV较健康组显著减低(P0.05)。结论:老年抑郁症患者中脑功能与结构异常的区域没有重叠,异常的脑功能与结构对于抑郁症神经病理机制的作用相互独立。 相似文献
10.
Lutz Lüdemann Daniel Prochnow Torsten Rohlfing Tobias Franiel Carsten Warmuth Matthias Taupitz Hagen Rehbein Dirk Beyersdorff 《Annals of biomedical engineering》2009,37(4):749-762
The aim of the present study was to quantify both perfusion and extravasation in the prostate to discriminate tumor from healthy
tissue, which might be achieved by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using a nonspecific low-molecular-weight
contrast medium (CM). To determine extravasation as well as tissue perfusion an inversion-prepared dual-contrast sequence
employing a parallel acquisition technique (PAT) was designed for interleaved acquisition of T
1-weighted images for extravasation measurement and
T2-weighted images for determination of the highly concentrated bolus with a sufficiently high temporal and spatial resolution
at an acceptable signal-to-noise ratio. Thirteen patients with proven prostate cancer were examined with the sequence using
a combined body-array prostate coil. Before pharmacokinetic evaluation the images were intensity-corrected and, if required,
motion-corrected. The pharmacokinetic model used to calculate perfusion, permeability, blood volume, interstitial volume,
transit time, and vessel size index included two compartments and a correction of delay and dispersion of the arterial input
function. The information provided by the dual-contrast sequence allowed application of a more elaborate model for evaluation
and enabled quantification of all parameters. Peripheral prostate tumors were found to differ from peripheral healthy prostate
tissue in perfusion (1.38 mL/(min cm3) vs. 0.23 mL/(min cm3), p = 0.004), mean transit time (2.88 vs. 4.88 s, p = 0.039), and blood volume (1.9 vs. 0.7%, p = 0.019). A inversion-prepared dual-contrast sequence acquiring T
1- and -weighted images with sufficient temporal resolution and signal-to-noise ratio was successfully applied in patients with prostate
cancer to quantify all pharmacokinetic parameters of inflow and extravasation of a low-molecular-weight inert tracer. 相似文献
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Sarang Byun Joshua Gordon Sarah Morris Tripti Jacob Nalini Pather 《Clinical anatomy (New York, N.Y.)》2019,32(6):836-850
In pediatric patients, peripheral anesthetic blockade of the sciatic nerve is useful for postoperative pain relief after orthopedic procedures of the lower limb. The identification of the sciatic and its branches relative to the surrounding anatomical structures of the knee significantly contribute to the successful nerve blockade. However, reports have demonstrated complications arising from the inadequate and inconsistent understanding of the anatomy of the nerves in the knee region. In addition, the paucity of information regarding the location of the nerves of the knee throughout the pediatric development needs to be addressed in order for peripheral nerve blockades to become more readily used among the pediatric population. This clinical imaging study therefore aimed to document and analyze the relative morphometric relationship of the nerves in the knee region throughout the different stages of pediatric development. The locations of the sciatic, tibial, and common fibular nerves were measured in relation to relevant anatomical structures in 142 pediatric magnetic resonance imaging and computed tomography. A strong correlation was found between age and the distance from the common fibular nerve to the semitendinosus muscle, and thus can be used to predict stature. Significant differences were found between males and females, specifically after puberty, suggesting that sexual dimorphism emerges more distinctively at puberty. In order to predict the location of the nerves at the popliteal fossa, a regression formula using the patient's age and bicondylar width was created. These finding may have significant implications for popliteal approach of the sciatic nerve blockade in pediatric patients. Clin. Anat. 32:836–850, 2019. © 2019 Wiley Periodicals, Inc. 相似文献
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Jong Kwan Park Jong Youn Kim Hyuck Moon Kwon Tae Hoon Kim Seung-Jin Oh Bum-Kee Hong Young Won Yoon Pil-Ki Min Sung Woo Kwon Byoung Kwon Lee 《Yonsei medical journal》2014,55(3):599-605