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161.
This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries (MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres. During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1: left MCA = 3.27 ± 1.9%; right MCA = 3.63 ± 2.1%; task 3: left MCA = 2.42 ± 0.7%; right MCA = 2.56 ± 1.3%); the negative emotional task was accompanied by a significantly higher increase in the right (11.31 ± 1.6%) than in the left MCA (4.72 ± 3.7%; analysis of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler ultrasound and suggest the involvement of the right hemisphere in emotional processing. Received: 4 March 1999 Received in revised form: 29 June 1999 Accepted: 5 August 1999  相似文献   
162.
Moyamoya病发生、发展及转归实验研究   总被引:4,自引:2,他引:2  
目的研究Moyamoya病的发生、发展及转归过程。方法建立Moyamoya病的实验动物模型。结果颈动脉逐渐狭窄或闭塞的过程是内弹力纤维变性、断裂后,中膜平滑肌细胞沿断裂处向内膜游走、深入增生的过程。早期,因侧支循环血管建立不完善,脑组织缺血、缺氧出现多灶性脑软化坏死。随时间延长,脑内大量小动脉及毛细血管代偿性增生,其血管壁腔大壁薄,形成异网。同时5个粟粒状或囊状动脉瘤.蛛网膜下腔、脑室内及脑实质内有小的出血灶。结论Moyamoya病临床表现早期以缺血性脑血管病为主,后期以出血性脑血管病为主,是由Moyamoya病理的演变过程所决定的,是疾病的发展规律。  相似文献   
163.
目的研究大鼠大脑中动脉缺血和再灌注模型中环氧合酶-2(COX-2)基因的表达。方法原位杂交方法。结果缺血30min再灌注组,血流再通4h后缺血区的大脑皮层有很强的表达并持续24h。缺血90min再灌注组和持续缺血组在缺血区以外的广泛大脑皮层显著表达,在海马的齿状回两侧及纹状体也发现表达。COX-2mRNA的表达可被MK-801抑制。而NBQX和倍他米松对其表达没有影响。结论在缺血区、缺血周边部、缺血远隔区有NMDA受体介导的COX-2表达,阐明上述区域花生四烯酸代谢活性化  相似文献   
164.
Cortical metabolites and regional cerebral intracellular pH (pHi) were measured in normoglycemic (NM), acute hyperglycemic (AH), and chronic hyperglycemic (CH, 2 week duration, streptozotocin-induced) Wistar rat brains during cardiac arrest and resuscitation. During total ischemia in AH and CH rats (plasma glucose approximately 30 mM), cortical ATP, PCr, glucose, and glycogen all fell significantly as expected. Lactate levels increased dramatically in association with a concomitant intracellular acidosis. Although lactate reached higher concentrations in AH and CH than NM, pHi was significantly lower only in the AH group. With 5 min of reperfusion, all groups recovered to near baseline in all variables, though lactate remained elevated. In a separate aspect of the study, animals from each experimental group were allowed to recover for 4 days following resuscitation, with outcome being gauged by mortality rate and hippocampal CA1 neuron counts. NM survival rate was significantly better than AH and CH. In particular, no CH rats survived for 4 days despite rapid initial recovery. After 4 days, the AH group had suffered significantly greater CA1 neuron loss than the NM rats. In summary, our research identified differences in intra-ischemic acid-base status in the two hyperglycemic groups, suggesting that chronic hyperglycemia may alter the brain's buffering capacity. These observations may account for differences between acutely and chronically hyperglycemic subjects regarding outcome, and they suggest that factors other than hydrogen ion production during ischemia are responsible for modulating outcome.  相似文献   
165.
Ornithine decarboxylase (ODC) transgenic and alpha-difluoromethyl ornithine (DFMO)-treated rats were exposed to transient middle cerebral occlusion (MCAO) to examine the role of intraischaemic ODC-activity on the evolution of ischaemia-reperfusion damage. Magnetic resonance imaging (MRI) data show that the damage develops slower in ODC transgenic than in DFMO-treated rats, which is not caused by a difference in perfusion. Furthermore, infarct volumes are smaller in the former animals one day later. These data support the idea of endogenous neuroprotective action of ODC.  相似文献   
166.
A case of schizophrenia-like psychosis (psychotic disorder not otherwise specified according to the DSM-IV criteria) with pericentric inversion on chromosome 9 [inv.(9) (p11; q13)] is reported. In this case, a minor brain anomaly, a small cyst in the left subcortex, was observed on magnetic resonance imaging of the brain. In the clinical course, prominent chronic hallucinations were observed; however, there was no evidence of the disorganization of personality, delusion, and deterioration in level of functioning that are usually seen in schizophrenia. This case and a review of the literature indicate that the pericentric region of chromosome 9 might be a potential areas of interest for the aetiology of psychiatric disorders. The phenotype-karyotype relationship of pericentric inversion on chromosome 9 and its relationship to psychosis are discussed.  相似文献   
167.
168.
Summary The purpose of this study was to compare the effect of hyper-ventilation and indomethacin on cerebral circulation, metabolism and pressures in patients with acute severe head injury in order to see if indomethacin may act supplementary to hyperventilation. Fourteen severely head injured patients entered the study. Intracranial pressure (ICP), mean arterial blood pressure (MABP) and cerebral perfusion pressure (CPP) were monitored continuously. Within the first four days after the trauma the CO2 and indomethacin vasoreactivities were studied by measurements of cerebral blood flow (CBF) (Cerebrograph 10a, intravenous133Xe technique) and arterio-venous difference of oxygen (AVdO2). Ischaemia was evaluated from changes in CBF, saturation of oxygen in the jugular bulb (SvjO2), lactate and lactate/oxygen index (LOI). Data are presented as medians and ranges, results are significant unless otherwise indicated. Before intervention ICP was well controlled (14.8 (9–24) mmHg) and basic CBF level was 39.1 (21.6–75.0) ml/100 g/min). The arterio-venous oxygen differences were generally decreased (AVdO2 = 4.3 (1.8–8.1) ml/100 ml) indicating moderate luxury perfusion. Levels of CMRO2 were decreased (1.54 (0.7–3.2) ml/100 g/min) as well.Duringhyperventilation (APaCO2 = 0.88 (0.62–1.55) kPa) CBF decreased with 11.8 (–33.4–29.7) %/kPa and ICP decreased with 3.8 (0–10) mmHg. AVdO2 increased 34.0 (4.0–139.2) %/kPa, MABP was unchanged, CMRO2 and CPP increased (CPP = 3.9 (–10–20) mmHg). AVD (lactate) and LOI were unchanged. No correlations between CBF responses to hypocapnia and outcomes were observed.An i.v. bolus dose ofindomethacin (30 mg) decreased CBF 14.7 (–16.7–57.4) % and ICP decreased 4.3 (–1–17) mmHg. AVdO2 increased 27.8 (–40.0–66.7)%, MABP (MABP = 4.9 (–2–21) mmHg) and CPP (CPP = 8.7 (3–29) mmHg) increased while CMRO2 was unchanged. No changes in AVd (lactate) and LOI indicating cerebral ischaemia were found.Compared to hyperventilation (changes per 1 kPa, at PaCO2 level = 4.05 kPa) the changes in MABP, CPP and CBF were significantly greater after indomethacin, while the changes in AVdO2, ICP, SvjO2, and LOI were of the same order of magnitude.Nocorrelation between relative reactivities to indomethacin and CO2, evaluated from changes in CBF and AVdO2, or between the decrease in ICP after the two procedures were found. Thus, some patients reacted to indomethacin but not to hyperventilation, and vice versa.These results suggest that indomethacin and hyperventilation might act independently, or in a complementary fashion in the treatment of patients with severe head injury.  相似文献   
169.
Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.)  相似文献   
170.
Summary Authors analised retrospectively the incidence of pituitary apoplexy in a series of 799 pituitary adenomas with respect to the long term follow-up of the patients.Focal vascular abnormalities in histological specimens of tumours, regarded as morphological suggestion of past apoplexy (heamorrhage, ischaemic infarction or necrosis), were established in 113 out of 783 surgical cases (14.4%).Acute clinical onset, justifying the clinical diagnosis of pituitary apoplexy, occurred in 39 patients only (5% of the whole series), 19 of them were subjected to urgent surgical decompression due to severe neurological deficit. The haemorrhagic character of apoplexy was established in most cases requiring immediate surgery.The detailed clinical picture of this condition and its management are discussed with respect to the long term prognosis.On this basis the authors suggest the necessity of surgical treatment in every case of pituitary apoplexy, taking into account not only neurological recovery, but also endocrine and oncological aspects of the disease. The observation that pituitary apoplexy may be a marker of tumour invasiveness (even in small, enclosed adenomas) is highlighted.  相似文献   
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