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1.
Traumaticopticneuropathyisavision threateningdisorder Autopsiesafterheadtraumahaveshownthattheopticnervesareoftendamagedmostseverelywithintheopticcanal 1 Althoughvariouskindsofmicrosurgicaldecompressionoftheopticcanalhavebeenadvocatedastheeffectivemeth…  相似文献   

2.
Bladdercarcinomaisthefourthmostcommoncancerwitharisingincidenceandtheleadingcauseofdeathinmen Approximately 70 %ofnewtumorsaresuperficial,andhaveagoodprognosis Theremaining 30 %aremuscle invasivewithapoorprognosis 1  Anumberofcytogeneticandmolecularanalysesh…  相似文献   

3.
Proliferativevitreoretinopathy (PVR)isoneofthemainreasonsforthefailureofretinaldetachmentsurgery Platelet derivedgrowthfactor (PDGF)andbasicfibroblastgrowthfactor (bFGF)arestronglychemotacticandmitogenictoPVRcellsinvitro 1  Inordertorevealtherolethesetwogro…  相似文献   

4.
P16proteinwasinitiallyfoundtobindwithcyclin dependentkinase4(CDK4)anddefinedasanegativeregulatorofthecellcycle 1  Sincethegeneencodingp16protein,multipletumorsuppressor 1(MTS1) ,wasfoundtobehomozygouslydeletedinmorethan 10 0tumorcelllines,2 ,3  manylaboratoriesinve…  相似文献   

5.
CT scanning and arthroscopic evaluation of patellofemoral malalignment   总被引:3,自引:0,他引:3  
Patientswithperipatellarpainfrequentlyhaveunderlyingpatellofemoralmalalignment Earlydiagnosis,however,maybedifficultbecauseofapoorcorrelationbetweenthepathologicalchangesoftrackingabnormalitiesandtraditionalradiographicviews Inaddition ,radiographicexam…  相似文献   

6.
Diagnosis and surgical treatment of posterior fossa solid hemangioblastomas   总被引:5,自引:0,他引:5  
Hemangioblastomasarebenignneoplasms,predisposedtogrowintheposteriorfossaandresponsiblefor 2 %ofallintracranialtumorsand 10 %ofallposteriorfossatumors Themajorityofhemangioblastomasiscysticwithmuralnodules,andiseasytodiagnosewithmodernneuroimagingmodalities…  相似文献   

7.
Long-term survey of outcome in acute promyelocytic leukemia   总被引:6,自引:0,他引:6  
Acutepromyelocyticleukemia (APL)isadistinctsubtypeofacuteleukemiacharacterizedbyabalancedreciprocaltranslocationbetweenchromosome 15and 17resultinginthechimericgeneencodingPML RARαprotein 1All transretinoicacid (ATRA)inducedifferentiationofpromyelocytesintom…  相似文献   

8.
Tumorigenesisproceedsthroughanaccumulationofspecificgeneticalterations Recentstudieshavefocusednotonlyonthederegulationofcellproductionbutalsoontheinhabitationofcellloss Thisstudyassessedtherelationshipbetweenapoptoticstatusandbiologicalbehaviorduring…  相似文献   

9.
Wilsondisease (WD)isalethalautosomalrecessivedisorderofcoppermetabolism ,andischaracterizedbyacuteorchronicliverdiseaseand/orneurologicdeficitsduetocopperaccumulationinliverandbrain Treatmentistoremovetheexcesscopperbychelatingagentssuchaspenicillamine1 …  相似文献   

10.
Chroniccutaneousulcersrepresentamajorhealth careproblemwithconsiderablesocioeconomicimpact 1,2Traditionally,localtreatmentofchroniccutaneousulcersconsistsofconstantlocalwoundcare ,surgery ,skingrafting,debridementandvascularreconstruction Chroniculcersmayi…  相似文献   

11.
Objective High resolution structural MR imaging can reveal structural characteristics of cerebral cortex and provide an insight into normal brain development and neuropsychological diseases. The aim of this study was to compare cortical structural characteristics of normal human brain between 3T and 7T MRI systems using surface-based morphometry based on high resolution structural MR imaging. Methods Twelve healthy volunteers were scanned by both 3T with 3D T1-weighted fast spoiled gradient recalled echo (3D T1-FSPGR) sequence and 7T with 3D T1-weighted magnetization-prepared rapid gradient echo (3D T1-MPRAGE) sequence. MRI data were processed with FreeSurfer. The cortical thickness, white and gray matter surface area, convexity, and curvature from data of 3T and 7T were measured and compared by pairedt-test. Results Measurements of mean cortical thickness, total white matter surface area and gray matter surface area of 3T were larger than those of 7T (left hemisphere:P=0.000, 0.006, 0.020 respectively; right hemisphere:P=0.000, 0.000, 0.000 respectively). Surface-based morphometry over the whole brain demonstrated both reduced and increased measurements of cortical thickness, white and gray surface area, convexity, and curvature at 7T compared to 3T. Conclusions Inconsistency of brain structural attribute between 3T and 7T was confirmed, and researchers should be cautious about data when using ultrahigh field MR system to investigate brain structural changes.  相似文献   

12.
Background Functional magnetic resonance imaging (fMRI) has become a powerful tool for tracking human brain activity in vivo. This technique is mainly based on blood oxygenation level dependence (BOLD) contrast. In the present study, we employed this newly developed technique to characterize the neural representations of human portraits and natural sceneries in the human brain. Methods Nine subjects were scanned with a 1.5 T magnetic resonance imaging (MRI) scanner using gradient-recalled echo and echo-planar imaging (GRE-EPI) pulse sequence while they were visually presented with 3 types of white-black photographs: natural scenery, human portraits, and scrambled nonsense pictures. Multiple linear regression was used to identify brain regions responding preferentially to each type of stimulus and common regions for both human portraits and natural scenery. The relative contributions of each type of stimulus to activation in these regions were examined using linear combinations of a general linear test. Results Multiple linear regression analysis revealed two distinct but adjacent regions in both sides of the ventral temporal cortex. The medial region preferentially responded to natural scenery, whereas the lateral one preferentially responded to the human portraits. The general linear test further revealed a distribution gradient such that a change from portraits to scenes shifted areas of activation from lateral to medial. Conclusions The boundary between portrait-associated and scenery-associated areas is not as clear as previously demonstrated. The representations of portraits and scenes in ventral temporal cortex appear to be continuous and overlap.  相似文献   

13.
Objective To study the activation changes of the brain in patients with amyotrophic lateral sclerosis (ALS) while executing sequential finger tapping movement using the method of blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (tMRI). Methods Fifteen patients with definite or probable ALS and fifteen age and gender matched normal controls were enrolled. MRI was performed on a 3.0 Tesla scanner with standard headcoiL The functional images were acquired using a gradient echo single shot echo planar imaging (EPI) sequence. All patients and normal subjects executed sequential finger tapping movement at the frequency of 1-2 Hz during a block-design motor task. Structural MRI was acquired using a three-dimensional fast spoiled gradient echo (3D-FSPGR) sequence. The tMRI data were analyzed by statistical parametric mapping (SPM). Results Bilateral primary sensorimotor cortex ( PSM), bilateral premotor area ( PA), bilateral supplementary motor area (SMA), bilateral parietal region ( PAR), contralateral inferior lateral premotor area ( ILPA), and ipsilateral cerebellum showed activation in both ALS patients and normal controls when executing the same motor task. The activation areas in bilateral PSM, bilateral PA, bilateral SMA, and ipsilateral cerebellum were significantly larger in ALS patients than those in normal controls ( P 〈 0.05 ). Extra activation areas including ipsilateral ILPA, bilateral posterior limb of internal capsule, and contralateral cerebellum were only detected in ALS patients. Conclusions Similar activation areas are activated in ALS patients and normal subjects while executing the same motor task. The increased activation areas in ALS patients may represent neural reorganization, while the extra activation areas in ALS patients may indicate functional compensation.  相似文献   

14.
目的:探讨快速液体衰减反转恢复(FAST FLAIR)序列在脑部疾病诊断中的应用价值。方法:108例脑缺血性疾病患者同时行T2加权FSE序列和FLAIR序列检查。结果:FLAIR序列显示异常信号病灶426个,T2加权FSE序列显示异常信号病灶324个,而且前者比后者边界显示清晰。结论:FLAIR序列在发现病灶数目,病灶与周围脑实质的对比度明显优于T2加权FSE序列。FLAIR序列在脑缺血性疾病诊断中的有较高的价值。  相似文献   

15.
林兰英  林群  林财珠 《医学综述》2009,15(24):3795-3797
功能磁共振成像(fMRI)是通过一定的刺激使大脑皮质各功能区在磁共振设备上成像的方法,可以反映大脑的神经活动水平,对大脑的神经活动能准确地进行功能检测,并在活体人脑定位各功能区。fMRI是一种全新的对人的认知功能进行评价的影像学手段。通过fMRI对术后认知功能障碍患者脑功能区改变的研究,可为术后认知障碍的临床早期预防、诊断和治疗提供客观和直观的影像学依据。  相似文献   

16.
Y X Fang 《中华医学杂志》1989,69(6):305-7, 22
Magnetic resonance imaging (MRI) was performed in 17 patients (with 24 tumors) before and after intravenous administration of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). Contrast enhancement was seen in 16 patients. The image pattern of enhancement is the same as that of CT. With 0.1 mmol/kg intravenous bolus injection, the best enhancement can keep for one hour. In brain, the degree of enhancement was greater than that seen with CT in 7 tumours, equal to it in 12 tumors, and less in zero. MRI distinguished between tumour and peritumoral edema to the same extent as did CT. No side-effects were encountered and there was no significant change in regular urine and blood tests after administration of Gd-DTPA. T1-weighted images of spin echo pulse sequence are the best pulse sequence to observe the enhancement. Gd-DTPA is of considerable value in MRI of the brain and spine.  相似文献   

17.
脑的功能磁共振( functional magnetic resonance imaging,fMRI)是利用磁共振成像生成反映脑血流变化的图像。它主要以实时无辐射的探测技术对特定的大脑皮层区域进行扫描,以此来观察大脑神经网络情况。血氧水平依赖功能磁共振(blood oxygen level dependent functional magnetic resonance imaging,bold-fMRI)主要是神经元活动引起血液动力的改变,是目前功能磁共振在临床研究方面应用广泛的一个技术。当大脑神经活跃时,其附近的血流及血流耗氧增加,顺磁性的去氧血红蛋白浓度的变化引起横向磁化豫缩短效应,也就是T2加权像信号,T2加权像信号的强弱间接反映局部脑神经活跃的情况。通过功能连接和弥散张量成像(diffusion tensor imaging,DTI)技术计算统计出哪些脑区在执行人的语言功能,进而针对这些脑区进行蒙医针灸和重复经颅磁刺激(repetitive transcranial magnetic stimulation,rTMS)两种治疗,来促进脑卒中后患者语言功能的恢复,血氧水平依赖功能磁共振则给临床治疗提供可靠的影像依据。  相似文献   

18.
目的评价液体抑制反转恢复 (FLAIR)序列在颅脑疾病中临床应用价值。方法对 6 3例颅脑疾病患者行常规FSET1、T2序列及FLAIR序列扫描。比较这些序列在显示颅脑病变的差异。结果在 6 3例颅脑疾病中 ,FLAIR像共显示病灶 14 7个 ,而T2加权像只显示 10 6个。有 4 1个病灶仅在FLAIR图像中显示 ,95个病灶的内部结构、边界在FLAIR像较T2 像显示清晰。结论FLAIR像显示颅脑中邻近脑沟、脑室旁 ,脑室及脑池内等部位病变的边界、大小、范围及内部结构优于T2 加权像。  相似文献   

19.
为探讨用MR重T_2加权显示脑部肿瘤的临床应用价值。对37例病人共进行了41次磁共振成像。应用快速自旋回波(FSE)无脂肪抑制的重T_2加权成像技术.结果在原发性颅内肿瘤中,重T_2加权均能显示瘤体内部组织的结构及瘤体周边组织的病变。在较大的转移瘤中显示了内部结构及瘤体周边组织病变。因此提示了重T_2加权能更好的显示肿瘤的内部结构及其周边组织的病变。与常规MRI检查结合可以提供更多的肿瘤内部信息,提高诊断的准确性。方法简单,安全。  相似文献   

20.
刘文涛 《当代医学》2011,17(28):44-45
目的探讨在满足诊断的前提下,完成危重脑梗死患者颅脑MR检查的最佳方案。方法对临床拟诊为脑梗死的90例危重患者(全部病例均经CT检查已除外急性出血)应用半傅里叶采集自旋回波序列(half-fourier acquisition SE-HF)、半傅里叶采集单次激发快速自旋回波序列(half-fourier acquisition singo-shot turbo-SE,HASTE)和平面回波成像序列(echo planar imaging,EPI)完成颅脑的T1WI、T2WI和DWI检查,对部分躁动患者辅以制动措施。结果 88例患者约在2分钟完成颅脑MR检查,满足了临床诊断的要求。结论超快速的颅脑MR检查是危重脑梗死患者进行颅脑MR检查的前提,而采取合理的序列组合是实现超快速颅脑MR检查的重要手段。  相似文献   

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