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1.
目的:采用基于纤维束空间统计分析(TBSS)的方法分析遗忘型轻度认知障碍(aMCI)患者DTI多参数图,以研究其全脑白质纤维束损害的特点以及可能的病理机制。方法:选取29例aMCI患者和30名正常老年人(正常对照组),对全脑进行1.5T磁共振DTI序列扫描。采用FSL软件对被试的DTI扫描数据进行预处理后对aMCI组、正常对照组的部分各向异性、平均弥散、轴向弥散、径向弥散图进行基于体素的全脑非参数统计学比较。结果:与正常对照组比较,aMCI组的双侧皮质脊髓束、双侧扣带束中部、双侧胼胝体、左侧内囊前肢、左侧外囊、双侧下额枕束、左侧上纵束、左侧膝状体内视路、右侧钩束、右侧视放射出现FA值减低;胼胝体膝部及体部、左侧皮质脊髓束、左侧内囊前后肢、左侧外囊、左侧上纵束出现MD值增加;DR值增高的区域与FA值类似;DA图未发现异常;左侧白质改变多于右侧。aMCI组全脑白质各参数图与简易智能精神状态检查量表(MMSE)评分没有相关性。结论:相对于正常老年人,aMCI患者脑内多发纤维束出现损害,其DTI多参数图改变特点提示白质纤维束的损害可能主要是由退行性改变(retrogenesis)导致的。DTI各参数图的改变可能无法反映患者总体认知功能障碍的严重程度,但这还需要进一步的大样本研究。  相似文献   

2.
目的:采用基于纤维束空间统计分析(TBSS)的方法分析遗忘型轻度认知障碍(aMCI)患者DTI多参数图,以研究其全脑白质纤维束损害的特点以及可能的病理机制.方法:选取29例aMCI患者和30名正常老年人(正常对照组),对全脑进行1.5T磁共振DTI序列扫描.采用FSL软件对被试的DTI扫描数据进行预处理后对aMCI组、正常对照组的部分各向异性、平均弥散、轴向弥散、径向弥散图进行基于体素的全脑非参数统计学比较.结果:与正常对照组比较,aMCI组的双侧皮质脊髓束、双侧扣带束中部、双侧胼胝体、左侧内囊前肢、左侧外囊、双侧下额枕束、左侧上纵束、左侧膝状体内视路、右侧钩束、右侧视放射出现FA值减低;胼胝体膝部及体部、左侧皮质脊髓束、左侧内囊前后肢、左侧外囊、左侧上纵束出现MD值增加;DR值增高的区域与FA值类似;DA图未发现异常;左侧白质改变多于右侧.aMCI组全脑白质各参数图与简易智能精神状态检查量表(MMSE)评分没有相关性.结论:相对于正常老年人,aMCI患者脑内多发纤维束出现损害,其DTI多参数图改变特点提示白质纤维束的损害可能主要是由退行性改变(retrogenesis)导致的.DTI各参数图的改变可能无法反映患者总体认知功能障碍的严重程度,但这还需要进一步的大样本研究.  相似文献   

3.
目的:探讨联合应用fMRI和DTI评价PVL患儿的脑性视觉损伤的价值.材料和方法:选取24名PVL患儿及24名无窒息史的健康儿童志愿者进行镇静的状态下fMRI及DTI检查,视觉刺激采用2HZ闪烁光,fMRI数据采用SPM2软件进行后处理(ROI),计算患儿组与对照组的激活像素数目.DTI数据采用MedINRIA软件进行后处理,根据矢量元素和部分各向异性值(FA值)生成彩色弥散张量图(DTI图),计算患儿与对照组视觉相关主要白质纤维束的FA值.将视觉激活图与彩色弥散张量图融合.结果:正常对照组的激活区位于初级视觉皮层,PVL患儿的激活区部分移位.PVL患儿枕叶平均激活像素数目较正常对照显著减少,视觉相关主要白质纤维束FA值较正常对照显著降低.PVL患儿视觉区激活像素数目与视觉相关主要白质纤维束FA值呈正相关.结论:联合应用BOLD-fMRI和DTI在评价缺氧缺血性脑损伤后视觉功能变化方面有较高的应用价值.  相似文献   

4.
目的 探讨扩散张量成像(DTI)技术在脑室周围白质软化症(PVL)合并脑瘫患儿术后脑白质恢复中的应用价值.方法 收集经临床诊断为PVL合并脑瘫患儿15例作为病例组,另选相匹配的正常儿童志愿者15例作为对照组,均进行常规MRI平扫及DTI检查,并获得各向异性分数(FA)图,测量病例组治疗前后与对照组皮质脊髓束(内囊膝、内囊后肢、大脑脚及脑桥水平)、基底节区核团(尾状核、豆状核)感兴趣区的FA值差异.结果 双侧内囊膝、内囊后肢、脑桥、胼胝体压部、膝部及双侧大脑脚的FA值在病例组治疗前、后(术后1个月)与对照组间有统计学差异(P<0.05),3组豆状核、尾状核的FA值无统计学意义.进一步两两比较,双侧内囊后肢、胼胝体压部、膝部任意2组间比较均有统计学差异,双侧内囊膝、脑桥、双侧大脑脚治疗前、后无统计学意义,双侧内囊膝、脑桥、双侧大脑脚治疗前与对照组间比较均有统计学意义(P<0.05).结论 DTI技术可显示脑白质细微结构变化,其FA值在PVL合并脑瘫患儿术后脑白质恢复中有一定参考价值,有助于指导临床医生进一步合理治疗.  相似文献   

5.
儿童脑室周围白质软化症的MR扩散张量成像研究   总被引:1,自引:0,他引:1  
目的应用MR扩散张量成像对脑室周围白质软化症(PVL)患儿和正常婴幼儿进行比较。方法对15例正常志愿者和15例PVL患儿进行了扩散张量成像扫描,测量双侧内囊后肢、双侧视放射和胼胝体膝部、压部的部分各向异性(FA)值,并对结果进行统计学比较。结果对照组和PVL组的右侧内囊后肢的FA值分别为0682±0399和0555±0087、左侧内囊后肢的FA值分别为0673±0043和0557±0030,右侧和左侧视放射的FA值分别为0437±0675、0429±0052、0351±0051、0339±0064,胼胝体膝部、压部的FA值分别为0696±0579、0756±0454、0564±0080、0586±0100,差异均有统计学意义(P<001)。结论扩散张量成像能提示纤维束的髓鞘化过程的延迟,反映儿童发育中脑白质微观结构的改变,在PVL的随访观察中具有较大的潜力。  相似文献   

6.
目的探讨磁共振弥散张量成像(DTI)与弥散张量纤维束示踪技术(DTT)对早期弥漫性轴索损伤(DAI)的诊断应用价值。方法对22例DAI早期(伤后10天内)患者(DAI组)及12例正常志愿者(对照组)分别行常规MR扫描及弥散张量成像扫描。在FA图上分别测量DAI组及对照组双侧半球白质感兴趣区(胼胝体压部、胼胝体膝部、内囊前肢、内囊后肢)部分各向异性(FA)值,将两组感兴趣区(ROI)平均FA值的差异进行比较,并对DAI组FA值与临床GCS评分进行相关性分析。运用弥散张量纤维束成像显示通过病灶的纤维束特征。结果病变组与对照组比较,DAI早期FA值(胼胝体压部0.647±0.069、胼胝体膝部0.615±0.043、内囊前肢0.541±0.065、内囊后肢0.639±0.035)较对照组(胼胝体压部0.748±0.045、胼胝体膝部0.729±0.058、内囊前肢0.622±0.038、内囊后肢0.667±0.027)FA值显著降低(P0.001)。胼胝体压部FA值的变化与GCS评分呈正相关(r=0.736,P=0.001)。DTT较好显示感兴趣区白质纤维束形态,更直观显示脑白质损伤程度。结论 DTI联合DTT是DAI患者检查的敏感方法,FA值评估是DAI程度的重要依据,DDT可观察神经纤维束受损范围。  相似文献   

7.
目的:利用磁共振扩散张量成像(DTI )评估急性一氧化碳(CO)中毒患者的脑结构损伤情况。方法25例急性(5.0 d±1.44 d) CO 中毒患者和37例性别、年龄、利手、受教育程度匹配的健康志愿者进行 DTI 扫描,获得扩散张量纤维束成像(DTT)图像,并分别测量双侧小脑半球(齿状核)、黑质、海马、额叶白质(侧脑室前角前下方、侧脑室体部上方)、尾状核头、苍白球、丘脑、内囊前肢、内囊后肢、枕叶白质(视中枢)、顶叶白质(侧脑室体部上方)及胼胝体膝部、压部共26个感兴趣(ROI)的各向异性分数(FA)值和表观扩散系数(ADC)值,进行组间配对 t 检验。结果病患组双侧苍白球、双侧内囊前肢、双侧黑质、右侧小脑、左侧额叶下部白质、右额叶上下部白质、胼胝体膝部的 FA 值显著低于对照组(P <0.05)。病患组右侧黑质、左侧苍白球的 ADC 值显著降低(P <0.05),病患组右额叶上下部白质及双侧枕叶白质 ADC 值显著升高(P <0.05)。结论急性 CO 中毒患者广泛脑微结构受损,提示脑微结构的原发损伤可能是 CO 中毒迟发性脑病潜在的病理生理基础。  相似文献   

8.
周福庆  龚洪翰  Chi-Shing Zee   《放射学实践》2010,25(11):1194-1197
目的:探讨复发-缓解型多发性硬化(RRMS)患者投射纤维定量扩散张量改变.方法:20例RRMS患者及年龄和性别相匹配的20例健康志愿者(对照组)行MRI扫描,获取常规MRI及DTI图像,分别进行测量分析,比较2组投射纤维的部分各向异性指数(FA)和平均扩散系数(MD)值的变化.主要纤维束包括丘脑前辐射(atr)、丘脑上辐射(str)、丘脑后辐射(ptr)、皮质延髓束(cpt)、皮质脊髓束(cst)等.结果:RRMS组患者与健康对照组的FA值比较:ptr(左侧:0.541±0.141 vs 0.628±0.153;右侧:0.512±0.079 vs 0.560±0.102)、cpt/atr(左侧:0.421±0.118 vs 0.503±0.104;右侧:0.437±0.064 vs 0.512±0.102)、cpt/ptr(左侧:0.405±0.056 vs 0.500±0.078;右侧:0.427±0.057 vs 0.496±0.083)、cpt/cst/str(左侧:0.476±0.115 vs 0.554±0.056;右侧:0.462±0.095 vs 0.520±0.074),RRMS组的FA值均较健康对照组低,2组间差异有统计学意义(P〈0.05);RRMS组患者atr的FA值(左侧:0.538±0.103,右侧:0.542±0.092)与对照组(左侧:0.564±0.087;右侧0.568±0.116)比较,差异无统计学意义(P〉0.05).RRMS组患者与健康对照组的MD值比较:cpt/ptr(左侧:0.928±0.102 vs 0.853±0.105;右侧:0.949±0.165 vs 0.859±0.141)、cpt/cst/str(左侧:0.811±0.137 vs 0.772±0.093;右侧:0.868±0.167 vs 0.784±0.128)的MD值差异有统计学意义(P〈0.05),RRMS组的MD值较健康对照组增高;RRMS组患者atr(左侧:0.898±0.143 vs 0.868±0.118;右侧:0.850±0.164 vs0.835±0.074)、ptr(左侧:0.874±0.203 vs 0.829±0.103;右侧:0.847±0.172 vs 0.802±0.075)、cpt/atr(左侧:0.856±0.187 vs 0.805±0.161;右侧:0.829±0.246 vs 0.820±0.093)的MD值和健康对照比较差异均无统计学意义(P〉0.05).结论:多发性硬化患者双侧ptr、cpt/atr、cpt/ptr、cpt/cst/str存在FA值减小,双侧cpt/ptr、cpt/cst/str存在MD值的增高,提示在投射纤维中上述白质纤维束存在结构改变,DTI可以作为反映RRMS投射纤维微观病理改变的敏感检查指标.  相似文献   

9.
目的:应用磁共振扩散张量成像(DTI)探讨男性精神分裂症患者治疗前两侧内囊前肢神经纤维束的微观结构改变。方法:对13例治疗前(病程〈5年)的男性精神分裂症患者(病例组)和11例年龄相匹配的男性健康志愿者(对照组)行DTI检查,在12个方向施加扩散梯度磁场,采用小兴趣区(ROI)法测量并比较两组受试者内囊前肢各向异性分数(FA)值和表观扩散系数(ADC)值的差异。结果:病例组左、右侧内囊前肢的FA值分别为0.587±0.034和0.620±0.042,ADC值分别为(7.349±0.414)和(7.359±0.340)×10-4mm2/s,对照组左、右侧内囊前肢的FA值分别为0.627±0.032和0.639±0.045,ADC值分别为(7.186±0.302)和(7.243±0.389)×10-4mm2/s。病例组左侧内囊前肢FA值低于对照组,差异有显著性意义(t=2.297,P〈0.05),两组右侧内囊前肢FA值和双侧内囊前肢ADC值的差异均无显著性意义(P〉0.05)。结论:治疗前男性精神分裂症患者白质微观结构发生改变,提示左侧丘脑与前额叶、扣带回前部相互联系的白质功能障碍,可以解释男性精神分裂症的一些临床症状和认知缺陷。  相似文献   

10.
目的:通过扩散张量成像(DTI)对Broca失语症患者的语言功能区相关纤维结构进行研究,探讨Broca失语症脑内白质结构改变的特征。方法:使用Siemens Trio 3.0T MR扫描机对30例Broca失语症患者和20例健康成人进行常规序列及DTI扫描,在Siemens Leonado工作站上进行后处理,计算Broca区、Wernicke区及弓状束的各向异性(FA)参数。结果:30例Broca失语症病变均位于左侧大脑半球。失语组左、右侧Broca区FA平均值分别为0.208±0.053及0.284±0.056,对照组左侧Broca区FA平均值为0.296±0.054,失语组左侧Broca区FA平均值与右侧及对照组差异均具有显著性意义(P均<0.05);失语组Wernicke区FA平均值左、右两侧差异无显著性意义(P=0.445>0.05);失语组左侧弓状束FA平均值较右侧及对照组左侧降低(以前部及中部为著),且差异均具有极显著性意义(P均<0.001)。结论:语言功能区的损伤可引起Broca失语症,其纤维通路的损伤亦可导致失语症的发生。  相似文献   

11.
12.
成批煤气爆燃烧伤的救治体会   总被引:1,自引:0,他引:1  
报道治疗因煤气泄漏爆炸烧伤病员7例,经应用MEBT技术积极救治,其中6例于伤后17天痊愈出院,另一例特重伤员也于伤后30天康复出院。作者认为:应严格按照MEBT/MEBO要求进行规范治疗,正确处理生命体征、休克、感染、脏器功能和创面的辨证关系。同时,不能忽视外科营养在过程中的重要作用,它是创面修复的物质保证。  相似文献   

13.
In situations of stress, such as clinical trauma, starvation or prolonged, strenuous exercise, the concentration of glutamine in the blood is decreased, often substantially. In endurance athletes this decrease occurs concomitantly with relatively transient immunodepression. Glutamine is used as a fuel by some cells of the immune system. Provision of glutamine or a glutamine precursor, such as branched chain amino acids, has been seen to have a beneficial effect on gut function, on morbidity and mortality, and on some aspects of immune cell function in clinical studies. It has also been seen to decrease the self-reported incidence of illness in endurance athletes. So far, there is no firm evidence as to precisely which aspect of the immune system is affected by glutamine feeding during the transient immunodepression that occurs after prolonged, strenuous exercise. However, there is increasing evidence that neutrophils may be implicated. Other aspects of glutamine and glutamine supplementation are also addressed.  相似文献   

14.
新疆石河子地区奶牛隐性乳房炎的调查与分析   总被引:1,自引:0,他引:1  
采用LMT法对新疆石河子地区三个规模化奶牛场泌乳牛群进行了隐性乳房炎检测,共检测994头泌乳牛3976个乳区.结果表明:奶牛隐性乳房炎阳性率为81.9%,乳区阳性率为49.1%.数据分析表明,不同年龄、胎次以及有无卧床奶牛的隐性乳房炎阳性率差异显著(P<0.05),后乳区的隐性乳房炎感染率显著高于前乳区感染率(P<0.05),隐性乳房炎乳区发生数也明显影响当日产奶量(P<0.05).  相似文献   

15.

Objectives

Women are resistant to neuromuscular fatigue compared to men in response to a range of exercise tasks. The sex differences in the neuromuscular responses to load carriage have yet to be investigated.

Design

Prospective cohort study.

Methods

Twenty-three male and 19 female British Army recruits completed a 9.7 km loaded march within 90 min, with the weight carried dependent on military trade (16 ± 2 kg for men and 15 ± 1 kg for women). Isometric maximal voluntary contraction (MVC) force of the knee extensors and vertical jump (VJ) height were examined pre- and post-loaded march to examine neuromuscular fatigue. Heart rate (HR) was recorded throughout and ratings of perceived exertion (RPE) was recorded following the march.

Results

HR was higher for women (173 ± 9 b min?1, 83 ± 6% heart rate reserve) than men (158 ± 8 b min?1, 72 ± 6% heart rate reserve) (p  0.001). RPE following the march was also higher for women than men (6 ± 2 vs 4 ± 2, respectively, p < 0.001). The loss in MVC force was greater for men than women (?12 ± 9% vs ?9 ± 13%, respectively, p = 0.031), however VJ height was impaired to a similar extent (?5 ± 11% vs ?5 ± 6%, respectively, p = 0.582).

Conclusions

The greater physiological stress during load carriage for women compared to men did not translate to a greater severity of knee extensor muscle fatigue, with women demonstrating fatigue resistance.  相似文献   

16.

Background

The local muscular endurance of knee flexors, during eccentric work in particular, is important in preventing or delaying kinematic changes associated with fatigue during treadmill running. This result, however, may not be transferable to overground running.

Objective

To test the hypothesis that overground running is associated with eccentric hamstring fatigue.

Methods

Thirteen runners (12 male and one female) performed an isokinetic muscle test three to four days before and 18 hours after a marathon. Both legs were tested. The testing protocol consisted of concentric and eccentric quadriceps and hamstring contractions.

Results

There were no significant differences between peak torque before and after the race, except that eccentric peak hamstring torque (both thighs) was reduced.

Conclusion

Overground running (running a marathon) is associated with eccentric hamstring fatigue. Eccentric hamstring fatigue may be a potential risk factor for knee and soft tissue injuries during running. Eccentric hamstring training should therefore be introduced as an integral part of the training programme of runners.  相似文献   

17.
目的:对42例肺心病慢性呼吸性酸中毒患者的80例次血气测定结果。方法:用不同的酸碱图(卡)及代偿公式进行酸碱类型的初步差别分析。结果:结合临床表现、各种影响因素与治疗反应等作出综合判定。结论:比较二种判定的差异,并提出较为实用、可靠的判断建议,以助于复合型呼吸性酸碱失衡的临床诊断与处理。  相似文献   

18.
Primary hyperoxaluria (PH1) is a rare inborn autosomal recessive metabolic disorder due to the deficiency of hepatic alanine-glyoxylate-aminotransferase. This deficiency results in excessive synthesis and urinary excretion of oxalate, inducing renal stone formation and deposition of calcium oxalate in the kidney, bone, myocardium, and vessels (systemic oxalosis, SO) in the most severely affected individuals. We report renal and skeletal changes in a 3-month-old girl with PH1 and SO. Intense cortico-medullary hyperechogenicity and increased homogeneous radiopacity of normal-sized kidneys suggested the diagnosis of SO. Skeletal survey showed osteopenia and characteristic symmetrical metaphyseal transverse bands in long bones, progressively becoming more dense and migrating towards the diaphysis. Multiple pathological and slowly healing fractures of the limbs occurred at the dense band level. A radiopaque rim was then observed in flat bones, epiphyseal nuclei, and vertebral bodies. Inflammatory granulomatous reaction, induced by the presence of oxalate crystals in the marrow spaces, coexisted with progressively evident radiological signs of secondary hyperparathyroidism, with partially overlapping features. The patient was treated by peritoneal dialysis and hemodialysis until combined liver–kidney transplantation. There are no previous reports of infants treated with hemodialysis for more than 2 years.  相似文献   

19.
Interventional oncology in private practice requires expert training and can be performed in a stand-alone facility for type 1 procedures in a hospital setting for type 2 and 3 procedures where subspecialized radiologists, state-of-the-art equipment, and postprocedure hospital monitoring are available. A multidisciplinary effort with oncologists, internal medicine physicians and anesthesiologists is necessary. The practice of interventional oncology requires around the clock availability, meticulous and established protocols and procedures and a financial investment. On the other hand, it is professionally gratifying because of constant technical advances and the impact on patients.  相似文献   

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