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991.
992.
Case report Leptomeningeal involvement in diffuse intrinsic brain stem gliomas is rarely diagnosed clinically and in majority of the instances diagnosed only on postmortem examination. We report two cases of diffuse pontine glioma diagnosed clinicoradiologically and treated with conventional radiotherapy.Observations On follow-up, both patients showed clinical features suggestive of meningeal spread although imaging for pontine tumor showed stable disease. Leptomeningeal disease in the spine was confirmed on imaging and in one case by cerebrospinal fluid examination also. During the follow-up of patients with pontine glioma, the possibility of leptomeningeal involvement must be borne in mind.  相似文献   
993.
A case of synovial chondromatosis of the proximal tibiofibular joint in addition to lateral and medial tibiofemoral spaces and patellofemoral joint has been presented.  相似文献   
994.
网络教育资源构建中Windows Media流媒体技术的应用与研究   总被引:1,自引:0,他引:1  
Windows Media流媒体由于交互性强、使用方便和效率高,使得在网络教育中的应用逐渐增多。本文讨论了Windows Media流媒体技术在网络教育和资源构建中应用的优势及其在设计、制作、发布、应用等各环节的相关理论和技术细节。  相似文献   
995.
目的: 观察细胞内游离Ca2+([Ca2+]i)在培养的不同发育阶段皮层神经元无镁诱导惊厥性损伤中的作用,探讨惊厥性脑损伤年龄依赖性的可能机制.方法:体外培养6 d、17 d的胚胎大鼠皮层神经元用无镁细胞外液处理3 h,或于无镁处理前用NMDA(N-甲基-D-门冬氨酸)受体拮抗剂或Ca2+通道阻滞剂预处理,用MTT代谢率测定的方法检测神经元损伤,以Fluo-3作标记用激光共聚焦显微镜扫描的方法检测[Ca2+]i.结果:体外培养6 d、17 d的神经元单纯无镁组MTT代谢率较同期对照组降低.应用MK-801 10 μmol*L-1、AP-5 50 μmol*L-1、尼莫地平10 μmol*L-1预处理后再给无镁处理,培养6 d、17 d的神经元MTT代谢率均不同程度高于同期单纯无镁组.培养6 d、17 d的神经元相对荧光强度之间差异有显著性,两者与基线荧光强度比较差异亦有显著性.应用上述各种拮抗剂后,[Ca2+]i改变的峰值均明显低于同期单纯无镁组.结论: 在体外不同发育阶段的神经元,短暂无镁处理诱导惊厥样放电所引起的神经元线粒体功能损伤以及[Ca2+]i改变程度不同.这种[Ca2+]i改变的年龄依赖性可能是惊厥导致神经元损伤的年龄依赖性的机制之一.NMDA受体-Ca2+通道激活是导致这种[Ca2+]i改变及神经元损伤的关键环节.  相似文献   
996.
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of age diagnosed with low-grade astrocytoma. Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy. Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008). Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the outcome.  相似文献   
997.
目的 了解蚌埠医学院在校学生心理状况 ,为素质教育提供服务。方法 采用症状自评量表 (SCL- 90 )对该校 1~ 4年级学生进行调查分析。结果 该校在校生有 5个因子得分高于全国大学生常模 ,高年级学生得分高于低年级 ,男女生在人际、抑郁、敌对、偏执等方面差异有显著性。结论 应针对大学生的心理特点 ,在大学院校进行心理健康教育。  相似文献   
998.
Using pupillometry and sympathetic skin responses we compared the changes in local and systemic autonomic function within one week of a migraine attack. We investigated whether the measurement of the pupillary light reflex provides further information on the pathophysiology of migraine. Forty-two migraine patients and forty-two healthy age-matched controls were included. The parameters that were measured were the amplitude of the pupillary light reflex, the pupil size at the beginning of the measurement, the latency, the velocity of constriction and the velocity at the end of the dilatation. The average pupil size was 6.43 mm in the migraine group and 6.7 mm in the control group (p < 0.01). Reduced velocity of constriction and smaller amplitude of constriction in migraine patients within two days of an attack were signs of a parasympathetic dysfunction (p < 0.05). The sympathetic skin response did not differ significantly between migraine sufferers and controls. These findings indicate that both parasympathetic and sympathetic nerves supplying the eye are involved in migraine headache presumably due to effects on the pericarotid sympathetic fibers and involvement of trigeminal-parasympathetic reflexes. Received: 24 July 2001, Accepted: 16 July 2002 Correspondence to K. Schepelmann, M. D.  相似文献   
999.
NK/LAK细胞对人口腔癌耐细胞药株杀伤活性的观察   总被引:1,自引:0,他引:1  
OBJECTIVE: To understand the relation between cytotoxic activity of immunologic effector cells and multidrug resistance of the tumor cells. METHODS: Continuous observation of the morphological changes and MTT colorimetry were employed to evaluate the cytotoxic activity of lymphokine-activated killer (LAK) cells and natural killer (NK) cells against multidrug-resistant (MDR) human oral carcinoma cell line-KBV200 (before and after reversal of MDR) and parental drug-sensitive cell line KB. The morphologic changes of LAK cells and the 3 target cell lines were observed continuously under inverted microscope 3 h after co-culture of LAK cells with one of three target cell lines respectively. The lysis rates of three tumor cell lines in response to co-culture with LAK or NK cells were determined using MTT colorimetry. RESULTS: In comparison with the parental drug-sensitive cell line KB, both KBV200 and its reserved cell line by verapamil (KBVV) showed earlier adherence and greater number of cells lysed by LAK. In MTT colorimetry assay, the cytotoxicity of both LAK and NK cells against the 3 cell lines was associated with the effector-to-target (E/T) cell ratio; the lysis rates of KBV200 and reversed KBV200 cells by verapamil in response to LAK and NK cells were higher than that of KB cells (P<0.05), but KBV200 and KBVV did not significantly differ (P>0.05). At the same E/T ratio, LAK cells possessed stronger cytotoxicity than NK cells against all the tumor cell lines (P<0.05). CONCLUSIONS: Immunologic effector cells possess strong cytotoxic activity against multidrug-resistant cell line KBV200. Modulation of MDR does not decrease the cytotoxic activity of the immunologic effector cells. The results of this study suggest that adoptive cell immunotherapy with immunologic effector cells may be of value in controlling the progress of MDR tumors.  相似文献   
1000.
目的 探讨Graves患者骨生化标志的改变。方法 对38例Graves患者进行血AKP、Ca、P、ICTP、DPD、BGP、U-HOP/Cr及BMD测定。结果 Graves组的BMD显著低于正常对照组(P<0.01),Ca、ICTP、DPD、BCP、U-HOP/Cr显著高于对照组,Graves组的BMD与ICTP和DPD,BGP有很好的相关性(r=0.36,r=0527、r=0.401)。结论 Graves组骨吸收增加,骨形成减少。  相似文献   
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