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61.
目的对比研究动脉血质子自旋标记(ASL)与动态磁敏感对比(DSC)MRI在急性脑缺血诊断中的应用价值。方法27例发病3d内的急性脑卒中患者,均采用3.0TMR行脉冲式ASL和DSCMR检查。观察2种技术的灌注表现,包括灌注不足、正常灌注、延迟灌注、过度灌注等,采用Mann—Whitney检验做定性分析。在扩散加权成像显示的病变部位及对侧正常半球的镜像区域分别确定3个感兴趣区(ROI),测量信号强度并计算信号强度比(病侧/对照侧),并将结果做配对t检验。结果定性分析显示27例患者中,2l例2种技术检查结果一致(灌注不足14例,正常灌注5例,过度灌注2例)。6例2种技术不一致,其中4例ASL显示灌注不足而DSC显示延迟灌注,2例ASL显示正常灌注而DSC显示延迟灌注,两者间差异无统计学意义(P〉0.05)。定量分析示,2种技术的病侧与对照侧信号强度比值ASL为0.7l±0.46,DSC为0.73±0.42,两者间差异无统计学意义(P〉0.05)。结论无创性ASL技术在检测灌注异常时与DSCMRI有相似的敏感性;ASL可与常规MR检查相结合,为临床诊断急性缺血性卒中提供有价值的信息。 相似文献
62.
63.
64.
Ian F. Dunn Pankaj K. Agarwalla Alexander M. Papanastassiou William E. Butler Edward R. Smith 《Child's nervous system》2007,23(10):1191-1194
Objective Approximately 10% of patients with neurofibromatosis I (NFI) patients will have central nervous system (CNS) tumors. The most
common of these are hypothalamic–optic gliomas, followed by brainstem and cerebellar pilocytic astrocytomas. While isolated
pilocytic astrocytomas in NFI are well described, the appearance of multiple pilocytic astrocytomas in an individual patient
is less common. The most frequent combination in NFI patients with more than one pilocytic astrocytoma is optic tract/hypothalamic
and brainstem. Other combinations are exceedingly rare; multiple pilocytic astrocytomas have only been reported once in the
cerebral hemispheres in a patient with NFI. This report presents the first documented case, to our knowledge, of multiple
pilocytic astrocytomas in the cerebellum of a patient with NF1.
Methods Case report.
Conclusion The finding of multiple cerebellar pilocytic astrocytomas in a patient with NF1 is important because it expands the spectrum
of presentations for patients with NF1 and also highlights specific diagnostic and therapeutic challenges faced by the treating
physicians. The genetic and molecular basis of NF1 is reviewed. Strategies of diagnosis and treatment outlined here are relevant
to both patients with NF1 and all patients with multiple posterior fossa tumors. 相似文献
65.
Understanding the mechanisms of food intake and obesity 总被引:2,自引:1,他引:1
E. T. Rolls 《Obesity reviews》2007,8(S1):67-72
66.
67.
输卵管卵巢脓肿与卵巢良性肿瘤的CT鉴别诊断 总被引:3,自引:1,他引:2
目的:分析输卵管卵巢脓肿的CT特征,探讨CT对输卵管卵巢脓肿与卵巢附件良性肿瘤的鉴别诊断价值。材料和方法:回顾性分析13例输卵管卵巢脓肿和11例卵巢良性肿瘤的CT表现。结果:绝经前患者输卵管卵巢脓肿12例(12/13例),良性肿瘤组4例(4/11例)。脓肿13例(13/13例)、良性肿瘤9例(9/11例),CT表现为附件区囊实性肿块,脓肿和良性肿瘤边缘轮廓模糊不清分别为11例(11/13例)和4例(4/11例),两组显示囊壁增厚和边缘层状增强分别为10例(10/13例)和2例(2/11例)。脓肿的子宫骶骨韧带增厚和骶前直肠周围脂肪模糊分别为10/13例和9/11例,而良性肿瘤组无1例发生。结论:附件脓肿壁增厚和层状增强,子宫骶骨韧带增厚及骶前直肠周围脂肪模糊有助于鉴别输卵管卵巢脓肿和卵巢良性肿瘤。 相似文献
68.
目的研究骨髓基质细胞(BMSCs)移植对大鼠局灶性脑损伤血管生成的影响,探讨BMSCs移植修复大鼠脑损伤的机制。方法制备大鼠局灶性脑损伤动物模型,进行BMSCs移植,通过免疫组织化学、电镜等观察移植局部内皮细胞及微循环的变化。结果BMSCs移植后,局部凝血因子FⅧ染色阳性细胞数增加,染色加深,出现血管样结构;局部微血管内膜较光滑,内皮细胞间可见紧密连接,细胞核形态较规则,基底膜较完整,微血管管腔受压缓解。结论BMSCs移植促进损伤区周围内皮细胞增殖和新生血管形成。损伤区局部微循环得以改善进而修复脑损伤。 相似文献
69.
F. Giangaspero C. Doglioni M. T. Rivano S. Pileri J. Gerdes H. Stein 《Acta neuropathologica》1987,74(2):179-182
Summary The monoclonal antibody Ki-67, which reacts with cells in the active part of the cell cycle, was used to evaluate immunocytochemically the growth fraction in 22 primary brain neoplasms. The percentage of labelled cells reflected the histological grade of malignancy of each neoplasms. High percentage of Ki-67-positive cells were observed in one choroid plexus carcinoma (60%), one primary melanoma of meninges (40%), three medulloblastomas (40%–50%), one anaplastic astrocytoma and six glioblastomas (10%–40%). One ependymoma had 7% positive cells. Rare positive cells (1%) were present in one pilocytic astrocytoma and one ganglioglioma. Except one negative case, the meningiomas (five cases) had values of positivity ranging from 1% to 6%. Two acoustic schwannomas were negative. These results suggest that immunocytochemical staining with the Ki-67 may be a useful method for measuring the growth fraction in brain neoplasms.Supported in part by Associazione Italiana Ricerca sul Cancro and Ministero Italiano della Pubblica Istruzione 相似文献
70.
Tadamasa Miyauchi Hiroshi Takiya Toshihiko Sawamura Eiji Murakami 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(4):206-209
Pericardial abscess is rare in healthy individuals, especially the amebic type. We report a case of pericardial abscess and
cardiac tamponade due to intrapericardial rupture of an amebic liver abscess. A 31-year old Japanese male complained of fever
to a local hospital. A liver mass was discovered in his left hepatic lobe by an abdominal echogram. He was referred to the
internal department of our hospital and was treated with quinolone antibiotics. Two weeks after medication, he suddenly complained
of epigastralgia and severe orthopnea and was admitted. Abdominal computed tomographic scan showed an enlarged liver mass,
and massive pericardial effusion suggested cardiac tamponade. He underwent an emergency subxiphoid partial pericardiectomy
under local anesthesia. 1,000 ml of light brownish fluid was removed and his condition improved. Although no ameba was cultivated
from the pus, the amebic serological test was positive. Metronidazole was administered and the patients was discharged 31
days after surgery. 相似文献