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61.
The objectives have been to establish evidence-based guidelines and identify controversies regarding the management of patients with brain metastases. The collection of scientific data was obtained by consulting the Cochrane Library, bibliographic databases, overview papers and previous guidelines from scientific societies and organizations. A tissue diagnosis is necessary when the primary tumor is unknown or the aspect on computed tomography/magnetic resonance imaging is atypical. Dexamethasone is the corticosteroid of choice for cerebral edema. Anticonvulsants should not be prescribed prophylactically. Surgery should be considered in patients with up to three brain metastases, being effective in prolonging survival when the systemic disease is absent/controlled and the performance status is high. Stereotactic radiosurgery should be considered in patients with metastases of 3–3.5 cm of maximum diameter. Whole-brain radiotherapy (WBRT) after surgery or radiosurgery is debated: in case of absent/controlled systemic cancer and Karnofsky Performance score of 70 or more, one can either withhold initial WBRT or deliver early WBRT with conventional fractionation to avoid late neurotoxicity. WBRT alone is the treatment of choice for patients with single or multiple brain metastases not amenable to surgery or radiosurgery. Chemotherapy may be the initial treatment for patients with brain metastases from chemosensitive tumors.  相似文献   
62.
BACKGROUND AND PURPOSE: The Doppler waveform patterns of loss of diastolic flow, appearance of retrograde diastolic flow, or no detectable flow in the cerebral arteries suggest significantly abnormal cerebral blood flow (CBF). A retrospective study was performed to show that significantly abnormal CBF alone, without clinical criteria, is not necessarily specific to brain death in the young pediatric population. PATIENTS AND METHODS: Forty-seven pediatric patients, from newborn to 4 years of age, were found to have significantly abnormal CBF, including 7 patients with loss of diastolic flow, 28 with retrograde diastolic flow, and 23 with no detectable cerebral flow on serial Doppler sonographic examinations. Their clinical data and sonographic results were collected and analyzed. RESULTS: Forty-two patients died, a few of whom had only transient improvement of cerebral flow. All of the patients with no detectable cerebral flow expired. Five patients survived with or without sequelae. Their underlying conditions that caused increased intracranial pressure were treated by medical and/or surgical intervention, and diastolic reversal of CBF corrected within 1 day in all 5. CONCLUSIONS: Although no detectable flow is a lethal sign, pediatric patients with loss or reversal of diastolic flow may survive with prompt and effective treatment. Using Doppler ultrasound to diagnose cerebral circulatory arrest should be done with caution in pediatric patients.  相似文献   
63.
目的 探讨CT检查对判断新生儿缺氧缺血性脑病 (HIE)预后的价值。方法 对 85例HIE患儿分别在生后 1周内、2周~ 2个月、3~ 6个月、1~ 1 5岁进行CT检查 ;同时在生后12~ 14d进行新生儿行为神经测定 ;在 1~ 1 5岁测定发育商判断预后。结果 生后 1周内CT结果分度为重度者预后不良率为 4 0 9% (9/ 2 2 ) ,为中度者预后不良率为 5 7% (3/ 5 2 ) ;2个月时CT随访结果异常者预后不良率为 6 0 0 % (6 / 10 ) ;CT结果中度且 12~ 14d的NBNA评分≥ 35分与 <35分者的预后差异无显著性 ,CT结果重度且 12~ 14d的NBNA评分 <35分者有 72 7% (8/ 11)预后不良。结论 生后 1周内CT分度及生后 1个月左右随访结果 ,同时结合临床、生后 12~ 14dNBNA评分对判断HIE患儿的预后、制定治疗方案及疗程有重要意义。  相似文献   
64.
Protein kinase C (PKC) activity was measured in rat brain with 2 h of middle cerebral artery (MCA) and common carotid artery (CCA) occlusion, using dual autoradiography of [14C]iodoantipyrine (IAP) and [3H]phorbol-12,13-dibutyrate (PDBu). In the ischemic brain, it required more than 120 min of incubation to obtain a plateau in PDBu binding. In contrast, the binding of PDBu in non-ischemic brain reached a plateau with incubation for 60 min. This delay of PDBu binding in the ischemic brain suggests that the affinity of this ligand is reduced due to a change in structure of the cell membrane caused by ischemia. PDBu binding in the ischemic brain increased significantly compared to the non-ischemic brain. This finding provides further evidence that excessive activation of PKC in the ischemic brain may play an important role in ischemic neuronal damage. ©1997 Elsevier Science B.V. All rights reserved.  相似文献   
65.
Abstract A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature.  相似文献   
66.
烟碱对脑M胆碱能受体信息跨膜转导的调节   总被引:1,自引:1,他引:0  
采用体外实验研究烟碱对大鼠脑M受体信息跨膜转导的调节作用.脑突触体以烟碱1.0μmol·L-1预处理后,[3H]l-二苯羟乙酸奎宁酯与M受体结合及解离动力学过程减慢.在溶脱的大脑皮层M受体与G蛋白复合体上,烟碱1.0μmol·L-1可减慢[35S]-腺苷5'-[γ-硫]三磷酸与G蛋白的结合,并增强M受体与G蛋白之间的偶联关系.烟碱0.1~1000μmol·L-1既不影响纹状体腺苷酸环化酶的基础活性,也不影响氟化钠激活腺苷酸环化酶的作用.烟碱0.1~30μmol·L-1浓度依赖性地提高脑细胞内Ca2+浓度.据此提出烟碱对脑M受体信息跨膜转导系统有多点调节作用.  相似文献   
67.
Alpha power (8–12 Hz) was monitored over the frontal, temporal, parietal and occipital lobes of the left and right cerebral hemispheres while participants mentally rotated three-dimensional shapes to match a specified target. By comparing the activational patterns generated during three experimental conditions, each designed to systematically isolate the involvement of the various subcomponents comprising this mental rotation task, it was suggested that the right frontal lobe mediates encoding and comparison/decision processes, while the left parietal and the left temporal region appear most involved in the generation of images and their mental rotation. A preliminary model describing the cooperative interaction of these cortical regions during mental rotation tasks is proposed.  相似文献   
68.
We demonstrate the effect of deep brain stimulation of the ventral intermediate thalamic nucleus on intractable action tremor, in a 72-year-old man suffering from neuropathy associated with monoclonal gammopathy.  相似文献   
69.
The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10−6 M. The median effective concentration (EC50) was 5.2×10−10 M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10−4 M) abolished CNP-induced vasodilation, whereas pretreatment with NG-monomethyl--arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved.  相似文献   
70.
电针对沙鼠急性脑缺血再灌注后神经原损伤的保护作用   总被引:9,自引:0,他引:9  
本实验利用沙鼠急性脑缺血再灌注模型,研究电针对脑缺血及再灌注各期脑电活动的影响及组织病理学的改变。结果表明:缺血10mln,脑电幅度受到严重抑制,甚至变平坦,总功率大大下降,再灌注后总功率难以恢复,在120min时仅恢复到缺血前的27.39±11.31%,以后即不再进一步恢复,电针组动物缺血10min再灌注后,脑电的恢复明显比对照组快,120min时恢复至缺血前的71.45±16.46%(P<0.01),240min时继续恢复至缺血前的75.27±18.43%。同时电针能明显减轻缺血10min后再灌注24小时的神经原缺血性损伤。结果提示:电针对急性脑缺血引起的神经原损伤具有保护作用,并能促进脑功能的恢复。  相似文献   
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