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1.
北京市神经外科研究所是国内培养神经外科人才的高端基地之一。近 10 年来,研究所培养了近 200名研究生,其中包括博士研究生 78 人,硕士研究生 120 人。通过对近 10 年来研究所硕士及博士研究生毕业就业情况梳理,分析三甲医院毕业生就业率、京内就业率、京外就业率及总体就业率情况,探讨提升研究所研究生培养质量的途径,以达到提高研究生核心竞争力的目的,以期对神经外科高层次的医学人才培养提供有益建议,为各级医疗卫生机构提供高层次的神经外科高端人才。  相似文献   
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《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
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目的研究伽玛刀照射对正常大鼠海马组织的放射生物学作用,探讨伽玛刀作用于正常脑组织的机制,为立体定向放射外科的开展提供理论依据。方法利用自行设计的伽玛刀动物定向头架,应用不同剂量的伽玛射线对大鼠海马组织进行照射,原位杂交观察c-fosmRNA和HSP70mRNA表达,免疫组化观察FOS、HSP70、GFAP和bcl-2蛋白表达。结果c-fosmRNA在照射后3h、7d出现2个高峰,HSP70mRNA在照射后1~3h即有表达。FOS、HSP70、GFAP和bcl-2蛋白表达随照射时间和部位的不同而各有自己的特点。结论自行设计的伽玛刀动物定向头架定位准确、可靠。c-fos和HSP70表达说明伽玛刀照射虽局限于海马,但引起的反应却是强烈的。bcl-2具有抑制电离辐射所致细胞凋亡作用,GFAP阳性细胞反应可作为脑组织损伤的一种标志。  相似文献   
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目的 观察神经元移行异常(neurona1 migration disorders,NMDs)动物模型脑组织的病理变化以及N-甲基-D-天门冬氨酸受体(n-methyl-d-aspartate receptor,NMDA)的表达.方法 三组Sprague-Dawley孕鼠分别在孕15天,孕17天以及孕19天接受2.25Gy的X射线照射约5分钟,其后代成年后即为NMDs动物模型.观察指标为:存活率、脑组织的病理变化以及皮层中NMDA的表达.结果 胚胎期较早接受射线的大鼠,存活率低,大脑皮层结构紊乱严重,皮层NRl和NR2A的表达高.结论 在NMDs的大鼠脑皮层中,NRl和NR2A表达增加,且其表达增加的程度能反映NMDs的严重程度.NMDA的上调可能是NMDs患者致痫的主要病因.  相似文献   
6.
血管内栓塞治疗椎基底动脉瘤(附245例报告)   总被引:24,自引:13,他引:11  
目的 本文总结245例椎基底动脉瘤血管内治疗经验。方法 本组1986年7月至2002年6月共收治245例椎基底动脉瘤,其中224例进行了血管内栓塞治疗。治疗方法包括:单侧椎动脉球囊闭塞术(51例),单纯弹簧圈栓塞术(107例),球囊再塑形技术加弹簧圈栓塞术(34例),支架加弹簧圈术(24例),单纯支架术(4例),可脱性球囊栓塞术(4例),21例中2例因导管不能到位放弃治疗,另外1例血管造影时出现脑梗塞,放弃治疗,其余18例因各种原因未治。结果 本组病例无一例死亡。有1例支架加弹簧圈栓塞术病例术后3小时出现脑干缺血症状经45天药物治疗症状消失,224例病人中有145例进行4个月至8年的复查或随访,宽颈动脉瘤有11例第一次栓塞术后复发,动脉瘤又有增大,其中有1例出现蛛网膜下出血,这11例中有5例又再次弹簧圈栓塞,另外6例因经济困难尚未继续栓塞治疗。结论 由于血管内治疗技术和材料的不断进步,绝大多数椎基底动脉瘤可以得到有效治疗,过去被视为“不治之症”的某些基底动脉梭形动脉瘤也取得了良好疗效。  相似文献   
7.
采用冷束缚法建立大鼠应激性溃疡模型,以探讨胃肠激素与应激性溃疡发病的相关性。实验组置于(4±2)℃环境,3H,对照组置于(18±3)℃,3h,分别检测不同时间血清胃泌素、胰高血糖素、生长抑素的水平。结果表明,实验组胃泌素、胰高血糖素水平明显高于对照组,生长抑素水平明显低于对照组。提示胃泌素、胰高血糖素、生长抑素可能从不同的角度参与了应激性溃疡的消长过程。  相似文献   
8.
目的 采用扩散张量成像技术揭示健康人Broea区与其他脑功能区间的纤维联系规律。方法 健康成人20名,采用Siemens Trio 3.0T MR仪及工作站行数据采集和后处理及Broea区(B45和44区)纤维追踪,分析由语言功能区发出的神经纤维分布和走行。结果 BroeaB45区纤维束平均值左侧为428束,右侧相应脑区为416束,两侧差异无统计学意义(t=0.216,P〉0.05);B44区纤维束平均值左侧为432束,右侧相应脑区为344束,两侧差异有统计学意义(t=2.314,P〈0.05)。B45区部分各向异性左侧平均为0.336,右侧同区为0.317(t=-3.656,P〈0.05);B44区左侧平均为0.342,右侧同脑区为0.342(t=0.093,P〉0.05)。弓状纤维束平均左侧为199束,右侧为205束(t=-0.465,P〉0.05);平均部分各向异性左侧为0.385,右侧为0.375(t=1.912,P〈0.05)。Broea区发出纤维走行和分布,主要向前上到额叶前部内侧面皮层下,过胼胝体到对侧相应结构,向外下穿外囊向后经颞叶到枕叶,向内下穿苍白球和内囊后肢向下行。结论 Broea区及其相关的纤维结构形成重要的语言纤维环路结构,结构完整是完成语言功能的基础。  相似文献   
9.
目的评价伽玛刀治疗无功能型垂体腺瘤的适应证和疗效。方法随访255例伽玛刀治疗后的无功能型垂体腺瘤,分成单纯伽玛刀治疗组与外科手术后加伽玛刀治疗组,平均随访时间34.2个月(6-90个月)。单纯伽玛刀治疗组187例,平均周边剂量14.6Gy;手术加伽玛刀治疗组68例,平均周边剂量13.5Gy。结果单纯伽玛刀治疗的187例无功能型垂体腺瘤中,肿瘤缩小127例(67.9%),肿瘤大小无变化的56例(29.9%),肿瘤增大4例(1.2%)。术后肿瘤残留或复发加伽玛刀治疗的68例无功能型垂体腺瘤中,肿瘤缩小45例(66.2%),肿瘤大小无变化21例(30.9%),肿瘤增大2例(2.9%)。本组随访255例肿瘤总控制率97.6%,出现新的垂体功能低下7例。结论伽玛刀治疗无功能型垂体腺瘤是有效和安全的,特别是开颅术后肿瘤残留和复发的病人,并发症少,优于常规放疗。  相似文献   
10.
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe. OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats. DESIGN: Observational contrast animal study. SETTING: Beijing Neurosurgical Institute. MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan. METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue. RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES. CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe.  相似文献   
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