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101.
采用低压低灌流方法造成家兔急性不完全性脑缺血,并进行重灌流。检测了脑电图(EEG)及大脑组织中乳酸脱氢酶(LDH)活性,观察了大脑皮层组织形态学变化。结果发现,脑缺血时大脑EEG明显抑制,LDH活性升高,脑组织超微结构表现为膜结构损伤。重灌流后EEG严重抑制,LDH活性升高,膜结构损伤进一步加重。 相似文献
102.
The distribution of the specific radioactivity and the incorporation into protein of [3H]-tryptophan and [3H]valine at varying layers from surface to centre were measured in incubated slices of cerebral cortices from infant and adult rats. Specific radioactivity in free amino acids was in both age groups highest in the intact surface layer. Incorporation of tryptophan into protein was even in slices from adult rats but much less than the average in the surface layers in slices from infant rats. Incorporation of valine exhibited similar heterogeneity in both age groups. The results suggest in brain slice preparations a zonal compartmentation of amino acid and protein metabolism which varies for different amino acids. 相似文献
103.
E. Johansson S. Mnsson R. Wirestam J. Svensson J.S. Petersson K. Golman F. Sthlberg 《Magnetic resonance in medicine》2004,51(3):464-472
Cerebral perfusion was assessed with 13C MRI in a rat model after intravenous injections of the 13C-labeled compound bis-1,1-(hydroxymethyl)-1-13C-cyclopropane-D8 in aqueous solutions hyperpolarized by dynamic nuclear polarization (DNP). Since the tracer acted as a direct signal source, several of the problems associated with techniques based on traditional dynamic susceptibility contrast (DSC) MRI contrast agents were avoided. Maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were calculated. The MTT was determined to be 2.8 +/- 0.8 sec. However, arterial partial-volume effects in the animal model prevented accurate absolute quantification of CBF and CBV. It was demonstrated that depolarization of the hyperpolarized 13C tracer via relaxation and the imaging sequence had little influence on CBF assessment when the time resolution of the imaging sequence was short compared to the MTT. However, CBV and MTT were increasingly underestimated as MTT or the depolarization rate increased if depolarization was not taken into account. With a modified bolus-tracking theory depolarization could be compensated for, assuming that the depolarization rate was known. Three separate compensation methods were investigated experimentally and by numerical simulations. 相似文献
104.
亚低温冬眠疗法治疗重度脑挫伤的临床研究 总被引:3,自引:0,他引:3
目的探讨亚低温冬眠疗法对重度脑挫伤病人的脑保护机理及临床疗效。方法46例重度脑挫伤患者(GCS≤8分)随机分为亚低温冬眠治疗组和常温治疗组。其中亚低温冬眠组22例,入院后4 ̄12h内行亚低温冬眠治疗,输液泵持续静脉点滴冬眠合剂,将肛温控制在32 ̄35℃,亚低温冬眠治疗4 ̄7d,同时检测颈动脉和颈静脉血气、电解质变化、血糖及生命体征等指标。常温组24例除未行亚低温冬眠治疗外,其余综合治疗及监测方法同亚低温冬眠组。两组病人均于伤后3个月根据GOS预后评分判定疗效。结果与常温组比较,亚低温冬眠治疗组脑氧耗明显降低,高血糖情况显著下降,生命体征及电解质等无明显差异,无严重并发症,死残率明显降低,预后显著改善。结论亚低温冬眠疗法具有显著的脑保护作用,临床应用于重度脑挫伤救治安全有效,无严重并发症。 相似文献
105.
目的探讨立体定向核团毁损术及脑深部电刺激术治疗非痉挛型脑瘫的疗效。方法将16例非痉挛型脑瘫病人分成三组:A组为肌张力障碍型,11例;B组为肌张力障碍合并震颤型,3例;C组为共济失调合并震颤型,2例。采用通用DT评分量表(GPS)评估病肢功能。分别采用立体定向核团毁损术及脑深部电刺激术治疗。术后随访1年,评估症状改善情况。结果A组肌张力障碍改善率为0—58.3%,平均17.1%;B组肌张力障碍改善率6.7%~25.0%,震颤改善率66.7%~75.0%;C组共济失调无明显变化,震颤改善率12.5%~25.0%。结论立体定向手术是治疗肌张力障碍型及震颤型脑瘫的可选择手段。 相似文献
106.
高血压鼠局部脑梗塞后脑超微结构改变动态观察 总被引:3,自引:0,他引:3
本文选用肾血管性高血压鼠(RHR)复制大脑中动脉闭塞(MCAO)模型,其后2h至7d分8次取不同区域脑组织进行透射电镜动态观察超微结构的改变。显示局部脑梗塞后发生全脑性改变,其损害程度和出现时间梗塞区最早,以坏死为主,呈完全不可逆性损害;边缘区稍后,主要是微血管塌陷和微血栓形成及部分脑细胞坏死,呈部分可逆性损害,远隔区和镜区最迟,以内皮和星形细胞水肿为主,呈可逆性损害,认为用RHR复制MCAO,更接近于高血压性脑血管损害基础上发生脑梗塞的临床病理改变,全脑超微结构的动态性改变中微血管损害起着重要作用。 相似文献
107.
Diffuse Axonal Injury (DAI) is not Associated with Elevated Intracranial Pressure (ICP) 总被引:7,自引:0,他引:7
Summary
Objective. Traditionally, intracranial pressure (ICP) monitoring has been utilized in all patients with severe head injury (Glasgow
coma score of 3–8). Ventriculostomy placement, however, does carry a 4 to 10 percent complication rate consisting mostly of
hematoma and infection. The authors propose that a subgroup of patients presenting with severe head trauma and diffuse axonal
injury without associated mass lesion, do not need ICP monitoring. Additionally, the monitoring data from ICP, MAP, and CPP
for a comparison severe head injury group, and subgroups of DAI would be presented.
Materials and methods. Thirty-six patients sustaining blunt head trauma and fitting our strict clinical and radiographic diagnosis of DAI were enrolled
in our study. Inclusion criteria were severe head injury patients who did not regain consciousness after the initial impact,
and whose CT scan demonstrated characteristic punctate hemorrhages of <10 mm diameter at the greywhite junction, basal ganglia,
corpus callosum, upper brainstem, or a combination of the above. Patients with significant mass lesions and documented anoxia
were excluded. Their intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were compared to a control group of
36 consecutive patients with severe non-penetrating non-operative head injury, using the Analysis for Variance method.
Results. Eighteen (50.0%), six (16.7%), and twelve (33.3%) patients had types I, II, and III DAI, respectively. The admission Glasgow
Coma Score (GCS) was higher for types I and II than for type III DAI. ICP was monitored from 23 to 165 hours, with a mean
ICP for 36 patients of 11.70 mmHg (SEM=75) and a range from 4.3 to 17.3 mmHg. Of all ICP recordings, of which 89.7% (2421/2698)
were ≤20 mmHg. Average mean arterial pressure (MAP) was 96.08 mmHg (SEM=1.69), and 94.6% (2038/2154) of all MAP readings were
greater than 80 mmHg. Average cerebral perfusion pressure (CPP) was 85.16 mmHg (SEM=1.68), and 90.1% (1941/2154) of all CPP
readings were greater than 70 mmHg. This is compared to the control group mean ICP, MAP, and CPP of 16.84 mmHg (p=0.000021),
92.80 mmHg (p=0.18), and 76.49 mmHg (p=0.0012). No treatment for sustained elevated ICP>20 mmHg was needed for DAI patients
except in two; one with extensive intraventricular and subarachnoid hemorrhage who developed communicating hydrocephalus,
and another with ventriculitis requiring intrathecal and intravenous antibiotic treatments. Two complications, one from a
catheter tract hematoma, and another with Staph epidermidis ventriculitis, were encountered.
All patients, except type III DAI, generally demonstrated marked clinical improvement with time. The outcome, as measured
by Glasgow Coma Score (GCS) and Glasgow Outcome Score (GOS) was similarly better with types I and II than type III DAI.
Conclusion. The authors conclude that ICP elevation in DAI patients without associated mass lesions is not as prevalent as other severe
head injured patients, therefore ICP monitoring may not be as critical. The presence of an ICP monitoring device may contribute
to increased morbidity. Of key importance, however, is an accurate clinical history and interpretation of the CT scan. 相似文献
108.
本文报道脑梗塞患者156例,就其发病情况,诱发因素,临床特点,治疗及预防进行了分析讨论。脑梗塞的发病高于脑出血,高血压动脉硬化是发生脑梗塞的主要危险因素。积极预防和治疗高血压有极其重要的意义。脑梗塞的治疗应根据脑水肿的情况进行,不宜普遍首先应用扩血管治疗。本病复发率高,反复发作可引起广泛性脑部损害,其病死率、病残率明显高于首次发病。小剂量阿斯匹林等药物应用对预防复发可能有一定作用。 相似文献
109.
110.
A 17-year-old man developed acute hemiparesis 6 months after a motor cycle accident. In the accident he had a closed trauma on the contralateral side of the head and the neck, with multiple bone fractures. Aortocervical angiography, performed after the infarction, revealed a 2.5 cm long aneurysmatic dilatation in the internal carotid artery, the presumably source of embolic infarction. This and the 24 other cases gathered from the literature support the notion that closed neck trauma may create "false aneurysm" which again may cause neurological deficits. 相似文献