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941.
Paraganglioma of the Cauda Equina Region – Report of two Cases and Review of the Literature 总被引:2,自引:0,他引:2
Summary A paraganglioma of cauda equina region is extremely rare and except for secreting tumour, the pre-operative diagnosis of
paraganglioma is very difficult. Two cases of non-functional paragangliomas of the cauda equina region are reported, one was
attached to the filum terminale and the other to a rootlet looking very much like a vascular neurinoma. Both were successfully
removed by surgery. An extensive review of the literature permits one to find 77 other cases. The clinical, radiological,
pathological (ultrastructural and immunohistochemical) features and surgical findings of all theses cases are discussed. Surgery
remains the treatment of choice. No effect of radiotherapy on recurrence prevention has ever been demonstrated. 相似文献
942.
P. Wunderbaldinger W. Schima K. Turetschek T. H. Helbich A. A. Bankier C. J. Herold 《European radiology》1999,9(6):1170-1182
Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly
growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately
36 million computer users are part of a worldwide network called the Internet or “information highway” and have created a
new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the
establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax
termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia
presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review)
and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both
information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive
database for radiologists. Since many radiologists and physicians have to be considered “Internet novices” and, hence, cannot
yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to
the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following
Internet address: http://www.univie.ac.at/radio/radio.html (Department of Radiology, University of Vienna)
Received: 2 February 1998; Revision received: 11 June 1998; Accepted: 27 July 1998 相似文献
943.
We report a case of central European tick-borne encephalitis with cervical myelitis presenting clinically as a lower motor
neuron syndrome of the upper limbs with proximal asymmetrical pareses and atrophies. There were no sensory deficits nor signs
of lesions of the spinal pathways or signs of encephalitis or meningitis. The affected motor fibers of the upper limbs were
electrically inexcitable, but sensory findings were normal. Electromyography of the paralyzed muscles revealed pathological
denervation activity without voluntary activation. The initial magnetic resonance imaging (MRI) showed a large hyperdense
lesion in the anterior part of the cervical cord from C3 to T1. Despite the fact that MRI changes disappeared completely within
6 weeks the patient showed only little improvement in the paralyzed muscles after 6 months. To our knowledge, these MRI changes
in patients with tick-borne encephalitis, consistent with an isolated anterior horn lesion, have never been reported previously.
The course may have been aggravated by an initial antibiotic treatment with cephalosporins.
Received: 4 May 1999 Received in revised form: 22 July 1999 Accepted: 26 July 1999 相似文献
944.
The genesis of immune privilege high in the evolutionary tree suggests that immune privilege is necessary, if not advantageous for the progressive development of the CNS. Upon reaching a certain degree of complexity, it seems as if the CNS was obliged to restrain the immune system from penetrating the blood-brain barrier. CNS autoimmunity against myelin proteins is known to be a contributory factor in the pathophysiology of multiple sclerosis and in the animal model of experimental autoimmune encephalomyelitis (EAE) (Wekerle, 1993). Such autoimmunity has therefore been regarded as detrimental and hence obviously undesirable. However, recent findings in our laboratory suggest that T-cell autoimmunity to CNS self-antigens (Moalem et al., 1999), if expressed at the right time and the right place, can do much good in the CNS. We shall review the experiments briefly, and then discuss their implications for our understanding of immune privilege and CNS maintenance after injury. 相似文献
945.
The mechanisms by which autoimmune diseases are triggered and by which the activation of autoreactive T cells is initiated and maintained are not yet fully understood. As the most potent antigen presenting cells (APC), and also being responsible for antigen transport as well as primary sensitisation of T cells, dendritic cells (DC) are capable of breaking the state of self-ignorance and inducing aggressive autoreactive T cells. In the development of autoimmune diseases, different types of DC exhibit distinct properties for inducing Th1/Th2 cell responses. Appropriate cytokines can convert immunogenic DC to tolerogenic DC. Utilizing the possibility to promote the tolerogenic effects of DC, a new therapeutic tool might soon become available to treat multiple sclerosis and other autoimmune diseases. 相似文献
946.
Recent evidence shows that neuropeptide expression in the CNS is markedly affected by seizure activity, particularly in the limbic system. Changes in neuropeptides in specific neuronal populations depend on the type and intensity of seizures and on their chronic sequelae (i.e. neurodegeneration and spontaneous convulsions). This paper reviews the effects of seizures on somatostatin-containing neurons, somatostatin mRNA and immunoreactivity, the release of this peptide and its receptor subtypes in the CNS. Differences between kindling and status epilepticus in rats are emphasized and discussed in the light of an inhibitory role of somatostatin on hippocampal excitability. Pharmacological studies show that somatostatin affects electrophysiological properties of neurons, modulates classical neurotransmission and has anticonvulsant properties in experimental models of seizures. This peptidergic system may be an interesting target for pharmacological attempts to control pathological hyperactivity in neurons, thus providing new directions for the development of novel anticonvulsant treatments. 相似文献
947.
锌激活体外培养大鼠成骨细胞肌醇磷脂信号转导系统 总被引:1,自引:0,他引:1
目的: 研究锌对体外培养大鼠成骨细胞肌醇磷脂信号转导系统的影响。方法: 从大鼠颅骨分离出成骨细胞,于 D M E M 培养基中进行传代培养。实验分为对照组、10μmol/ L、25μmol/ L 及50μmol/ L Zn2 + 剂量组:分别测定了 Zn2 + 对成骨细胞长期或短期作用后蛋白激酶 C( P K C) 活性及三磷酸肌醇( I P3) 含量的变化。根据被磷酸化多肽底物的量测定 P K C 活性,按照3 H m yo 肌醇掺入及层析分离法测定 I P3 含量。结果: (1) 三个不同剂量的 Zn2 + 作用于大鼠成骨细胞3 天后, I P3 含量及 P K C 活性均显著高于对照组;且随着 Zn2 + 剂量的增加, I P3 含量及 P K C 活性有相应增加的趋势;(2) 在短期实验中,25μmol/ L Zn2 + 对成骨细胞的作用比较明显,仅作用15 分钟, I P3 含量即明显提高,且在以后的各个作用时点均明显高于对照组,但时间效应曲线平坦;50μm ol/ L Zn2 + 组 I P3 含量在各个时点略低于25μmol/ L Zn2 +组;10μm ol/ L Zn2 + 组略高于对照组。25μmol/ L Zn2 + 、50μm ol/ L Zn2 + 组 P K 相似文献
948.
CONTENT: This article reviews the literature on the effectiveness of office system interventions to improve behavior-change counseling in primary care. These instructions consist of two principle components: tools and teamwork. Tools have been developed to assist providers with health risk assessment (questionnaires, health risk appraisals), prompting and reminding (chart stickers, checklists, flow charts, reminder letters), and education (manuals and handbooks). Teamwork entails the coordination and delegation of tasks between providers and staff. CONCLUSIONS: A number of clinical trials, particularly in the area of smoking cessation, have demonstrated the effectiveness of tools and teamwork for increasing counseling rates and counseling effectiveness. Although no one type of tool or method of teamwork is consistently more effective than another-with effectiveness varying according to practice, provider, and patient characteristics-the use of different tools and teamwork approaches leads to additive improvements in counseling and patient behavior-change rates. More high-quality research is needed, particularly in the areas of health risk assessment and electronic reminder systems, to develop effective office interventions that can be readily implemented into a wide variety of primary care practices. 相似文献
949.
医疗制度改革形势下中医医院的发展分析 总被引:2,自引:2,他引:0
笔者首先回顾了中医医院的发展历程。随后指出中医医院利用与产出效益较好,医疗费用低。但病床利用率低下,业务工作量下降,与此同时,中医医院还面临医疗保障制度改革、资产与西医院比的差距大、医疗体间竞争激烈、中医院内涵建设未跟上时代等的挑战。为此,中医医院发展的策略是加强医疗市场的宏观调控和微观运行的改善方可适应新的形势,求得发展。 相似文献
950.
医保与医院信息管理系统接口软件的探讨 总被引:6,自引:0,他引:6
厦门医疗保险信息管理系统是以城域网为主干的大型计算机管理系统,已正常运转了两年。作为医疗保险定点医疗机构上网的有51 所,其中,全部三级医院和大部分二级医院已开发应用信息系统。因此,医保系统与医院系统的接口问题必须得到解决。接口软件必须达到3 个要求:医疗消费数据的唯一性、医保系统的安全性、高效快速的性能。医保系统与医院系统的接口采用3 种方案:无缝、数据扫描、数据包交换。通过这3 种方案,较好地解决了接口问题 相似文献