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51.
52.
Jun Suk Huh Sang Keun Park Jun Jae Shin Tae Hong Kim 《Journal of Korean Neurosurgical Society》2007,42(4):342-345
The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature. 相似文献
53.
目的观察保罗样激酶1基因(plk1)沉默对胶质瘤细胞株-H4体外生长的抑制作用,探讨plk1基因作为胶质瘤治疗靶点的可行性。方法化学合成小片断干扰RNA(siRNA)抑制plk1基因的表达,Western blot检测plk1蛋白质的表达变化,流式细胞仪检测H4细胞周期分布及凋亡程度的变化,体外侵袭实验检测H4细胞侵袭能力的变化,MTT法检测H4细胞增殖速度的变化。结果经siRNA作用48h后,plk1蛋白质水平明显降低;较多的H4细胞聚集于G2/M期附近(P<0.05);细胞凋亡明显上升(P<0.05);细胞体外侵袭能力下降(P<0.05);增殖速度明显缓于对照组(P< 0.05)。结论靶向plk1的siRNA可在体外抑制胶质瘤细胞H4的侵袭与增殖,plk1有可能成为新的潜在胶质瘤治疗靶点。 相似文献
54.
目的 观察亚低温(33℃)对大鼠短暂性脑缺血后神经元的保护作用。方法 32只DS大鼠分为假手术组、常温缺血组和即刻亚低温组,采用尼氏体亚甲蓝特殊染色观察存活神经元、原位细胞凋亡检测法(TUNEL染色)检测及电镜观察脑缺血后大鼠CA1区神经元凋亡情况。结果 与假手术组相比,常温缺血组海马CA1区存活的锥体细胞数目减少(P<0.01);与常温缺血组相比,亚低温缺血组海马CA1区存活的锥体细胞数目明显增多(P<0.01)。亚低温缺血组大鼠海马CA1区TUNEL染色阳性细胞数目明显少于常温缺血组(P<0.01)。结论 脑缺血后迟发性神经元死亡很可能通过凋亡途径,亚低温对缺血后神经元的保护作用与减少神经元凋亡有关。 相似文献
55.
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The common ultrasonographic features of pilomatricoma. 总被引:3,自引:0,他引:3
OBJECTIVES: The purpose of this series was to describe typical ultrasonographic features of 20 cases of pilomatricoma and to improve its diagnostic rate with the use of an ultrasonographic approach. METHODS: For 20 pilomatricomas in 19 patients with preoperative ultrasonography from 1995 to 2004, we reviewed age, sex, symptoms, duration, referring clinician, and tumor sites. The ultrasonographic findings were retrospectively analyzed for tumor location, shape, size, margin, echo texture, echogenicity, presence, amount, and shape of calcification, presence of a hypoechoic rim, and Doppler flow pattern. RESULTS: The mean age of the 19 patients was 6.9 years (range, 1-21 years), and the female-male ratio was 1.1:1. Patients had a painful palpable mass in 10 cases (50%). Nine lesions occurred in the neck, 5 in the cheek, 2 in the preauricular region, and 4 in the extremity. All tumors were located in the subcutaneous layer. The mean size of the tumors was 13.4 mm. Fourteen pilomatricomas (70%) appeared as well-defined oval masses. Tumors were heterogeneously hyperechoic in 80% of cases. All tumors had internal echogenic foci. A hypoechoic rim was seen in 17 cases (85%). Doppler flow signals were observed in the peripheral region in 14 cases (70%). A correct preoperative diagnosis was made in 33% on the basis of clinical findings and in 76% by ultrasonography. CONCLUSIONS: Diagnosis of pilomatricoma should be considered when a well-defined mass with inner echogenic foci and a peripheral hypoechoic rim or a completely echogenic mass with strong posterior acoustic shadowing in the subcutaneous layer of the head, neck, or extremity is found on ultrasonography. 相似文献
57.
Jong Hun Kim Kwang-Yeol Park Sang Won Seo Duk L. Na Chin-Sang Chung Kwang Ho Lee Gyeong-Moon Kim 《JOURNAL OF CLINICAL NEUROLOGY》2007,3(1):62-66
The retrosplenial cortex is a cytoarchitecturally distinct brain structure located in the posterior cingulate gyrus and bordering the splenium, precuneus, and calcarine fissure. Functional imaging suggests that the retrosplenium is involved in memory, visuospatial processing, proprioception, and emotion.We report on a patient who developed reversible verbal and visual memory deficits following a stroke. Neuropsychological testing revealed both anterograde and retrograde memory deficits in verbal and visual modalities. Brain diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) demonstrated an acute infarction of the left retrosplenium. 相似文献
58.
Yu Ri An Jeong Han Seung Jun Kim Moon-Ju Oh Jung-Hwa Oh Seok-Joo Yoon Seung Yong Hwang 《Toxicology and Environmental Health Sciences》2010,2(4):245-250
It is important to acknowledge the harmful effects of environmental chemicals in human’s lives. The toxic effects of Diethylstilbestrol (DES), one of the endocrine-disrupting chemicals (EDCs), have been documented in many studies. As expected, DES affect male gendal hormone as well as female’s; therefore, epigenetic study should be considered. In this study, microarray technology was used to study harmful effects on the level of genomics, and here, two types of microarray chips- the Agilent mouse genome 4 × 44 K array for gene expression profiling and the Agilent mouse miRNA v13 for miRNA expression profiling-was used to study the relation between gene and miRNA expression profiles. As a result, we identified 4 miRNAs (miR 203, 350, 421, and 466i) that were similarly expressed at 3 hrs and 24 hrs of DES treat times. Twenty one genes matched between predicted target for 4 miRNAs and 118 genes expressed similarly. These genes have functions related to cell differentiation and cell cycle. Therefore, DES affects cellular function and induces toxicity in TM4 cells. In future studies, it is necessary to find more related functions and mechanisms of DES in the system. 相似文献
59.
60.
Hy De Lee Euy Young Soh Hoon Sang Chi Byong Ro Kim Kyong Sik Lee Kyung Soon Song Hyun Joo Jung 《Surgery today》1990,20(2):180-185
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in
relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed
significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02
per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer
patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic
nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis
in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05)
than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without
axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy. 相似文献