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排序方式: 共有10000条查询结果,搜索用时 13 毫秒
41.
我科于1999年10月以来,对各种原因引起的脑出血(出血量≥30 ml)的患者采用贾保祥[1]教授研制的微创颅内血肿清除术进行治疗,取得了良好效果。现报告如下。1临床资料1.1一般资料本组65例,男38例,女27例,发病年龄32岁-83岁,平均年龄56.2岁。其中高血压引起的脑出血63例,急性硬膜下血肿2例,超早期(发病7 h内)就诊28例,早期(发病7 h~3 d)就诊35例,延期(发病3 d以上)2例。1.2临床表现大部分患者发病早期均有头痛或头晕,其中呕吐52例,有高血压史者59例,有头部外伤史2例。神志清醒者17例,昏迷48例,其中深昏迷18例,中度昏迷21例,浅昏迷9例。61例偏瘫… 相似文献
42.
中药蝶脉灵注射液在心肺复苏中脑保护作用的实验研究 总被引:1,自引:0,他引:1
目的 探讨中药蝶脉灵注射在心脏骤停时对脑复苏的作用。方法 用电刺激导致室颤制备家兔心脏骤停模型,在光镜和电镜下观察大剂量肾上腺素治疗时,蝶脉灵注射液对脑组织的影响。结果 蝶脉灵注射液对脑细胞有明显的保护作用。结论 蝶脉灵注射液能明显改善心脏骤停时脑缺血性损害,因而有利于脑复苏。 相似文献
43.
Motor loss and swallowing difficulty after stroke: frequency, recovery, and prognosis. 总被引:8,自引:0,他引:8
Data relating to motor loss and swallowing difficulties in a community sample of 976 patients who suffered an acute stroke have been analysed. About 17% of patients seen within one week had no paralysis; at 6 months 48% of survivors had no paralysis and 9% had severe paralysis. The Motricity Index used to study motor loss related to functional loss and walking ability; it seems to be a simple valid measure of motor loss. Severe paralysis was associated with a high fatality rate, and only 6%-10% of survivors of an initially severe paralysis made a full recovery by 6 months. If severe persisted at 3 weeks, full recovery was not observed. Loss of sitting balance was associated with a poor outcome. Of conscious patients seen within one week, 14% choked on attempting to swallow and a further 28% had abnormal swallowing: this 42% of patients had a high fatality rate. 相似文献
44.
Antonella d’Arminio Monforte Paola Cinque Luca Vago Aleandro Rocca Antonella Castagna Cristina Gervasoni Maria Rosa Terreni Roberto Novati Andrea Gori Adriano Lazzarin Mauro Moroni 《Journal of neurology》1996,244(1):35-39
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination
to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents.
CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr
virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR
was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one
autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven
and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive)
were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma
therapy affected the sensitivity of both histological and CSF-PCR methods.
Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996 相似文献
45.
N. Çeviker M. K. Baykaner M.D. I. S. Keskil H. Sencer Ö. Ataoğlu M. Özsoy Z. S. Ercan 《Acta neurochirurgica》1995,132(1-3):104-109
Summary In this study intra-arterial Endothelin-1 was applied to rabbit basilar arteries and morphological findings were compared between two groups who were either perfusion fixed or immersion fixed. We planned to establish the quantitative dimension of the drug-induced morphological alterations, independent of the fixation technique's effect.There was an abundance of collagenous fibres deposited among the smooth muscle cells which was not observed in control arteries and after immersion fixation. These degenerative changes are similar to the finding following subarachnoid haemorrhage. The only fixation-related difference was the fact that lamina elastica interna was not corrugated in the perfusion fixation group.It is concluded that, the observed changes in the connective tissue of the arterial wall alter the passive elastic properties and so affect the degree of the response to the vasoactive messengers. 相似文献
46.
采用不同的血液动力学方法,对犬网膜下腔出血后引起的症状性脑血管痉挛进行治疗,我们发现:(1)等容称释加胞二磷胆碱和多巴酚丁胺疗法与人工扩容疗法疗效相同,但与等容稀释加胞二磷胆碱疗法相比,疗效有显著性差异,前者尤其知于扩容稀释禁忌证的病人;(2)稀释剂中加入胞二磷胆碱,可使红细胞变形能力半加,改善脑微循环(3)大剂量应用多巴胺升压,部分病例可使CVS加重,临床应慎用。 相似文献
47.
The anisotropy of the water diffusion tensor inside brain causes contrast in diffusion images, which depends on the relative orientation of the diffusion gradients and the subject. Because the trace of a tensor is invariant upon rotation, measurement of this trace can reduce the orientation effect. A family of imaging pulse sequences is presented in which the signal intensity is weighted by the trace of the diffusion tensor in a single scan. The methods are demonstrated for chicken gizzard in several orientations with respect to the gradient frame of reference, and for ischemic injury in cat brain after middle cerebral artery occlusion. The sensitivity of the techniques to the presence of background gradients is measured and discussed in detail. As a result, pulse sequences are suggested that provide reliable diffusion constants in both homogeneous and inhomogeneous magnetic fields. The efficiency of the techniques for clinical application is also evaluated. 相似文献
48.
We have investigated the regulation of anN-methyl-d-aspartate (NMDA) receptor-mediated synaptic potential by γ-aminobutyric acid (GABA)-mediated inhibition using extracellular and whole-cell voltage clamp recordings in rat auditory cortex in vitro. Single afferent stimulus pulses at low intensity elicited a slow extracellular negativity (Component C) that was mediated by NMDA receptors. At higher intensities, Component C was suppressed by recruitment of GABAergic inhibition. To understand the actions of GABAergic inhibition on Component C, we determined the effects of: (i) paired-pulse stimulation, which depresses GABAergic inhibition; (ii) pharmacological antagonism of GABA receptors; and (iii) afferent stimulation in slices from neonatal rats prior to the development of cortical inhibition. The results indicate that GABAergic inhibition prevents Component C fromoccurring, thereby preventing its reduction upon repeated stimulation. Whole-cell voltage clamp recordings were used to test the hypothesis that GABAergic suppression occurred by way of membrane hyperpolarization. At hyperpolarized holding potentials no NMDA receptor-mediated synaptic current was elicited, even with paired-pulse stimulation. At depolarized holding potentials a significant NMDA synaptic current was elicited despite the presence of GABAergic synaptic currents. We conclude that membrane hyperpolarization by GABAergic inhibition prevents the appearance and subsequent fatigue of an NMDA receptor-mediated synaptic potential. Reduction of inhibition can act as a ‘switch’ to fully release the NMDA potential as frequently as once every 10–20 s. 相似文献
49.
Summary The authors report a case of tentorial sinus draining the telencephalic and diencephalic tributaries of the basal vein. Dorsally the sinus joined the straight sinus and later the confluence of the sinuses. Attention should be paid to this normal variation whenever a transtentorial surgical approach is considered.
Sinus de la tenteAspect radiologique et anatomique, à propos d'un cas
Résumé Les auteurs rapportent un cas de sinus de la tente du cervelet drainant les affluents télencéphaliques et diencéphaliques de la veine basale. En arrière, le sinus rejoint le sinus droit puis le torcular. Une attention particulière pré-opératoire devrait être accordée à la mise en évidence de cette variété lorsqu'une approche transtentorielle est discutée.相似文献
50.
The effects of vasopressin on membrane potential and tension were studied in isolated segments of basilar arteries from the
University of Iowa colonies of normotensive inbred Kyoto-Wistar rats (WKY) and stroke-prone spontaneously hypertensive rats
(SP-SHR). In the presence of vasopressin (0.01–0.3 IU/ml), basilar arteries from WKY, but not from SP-SHR, developed rhythmic
contractions. These contractions were recorded in 13 of 14 WKY basilar arteries, were unaffected by pretreatment with 6-hydroxydopamine,
and were characterized by 20–100 dyne oscillations in tension, occurring 1–3 cycles/min, and superimposed on the vasopressin-induced
contraction (averaging 60 dynes at 0.01 IU/ml or 160 dynes at 0.3 IU/ml). However, resting membrane potentials were not different
in SP-SHR vs. WKY at 37°C, and both strains showed about the same (11 mV) depolarization by 0.1 IU/ml of vasopressin. The
rhythmic contractions were enhanced by K+-free solution, and abolished in the presence of high K+ solution (30 mM), suggesting that active Na+−K+ transport may be involved in modulating the rhythmic activity. These findings are consistent with the hypothesis that the
vasopressin-induced rhythmic contractions in WKY basilar arteries are at least partly dependent on a reduced activity of electrogenic
Na+−K+ active transport in WKY as compared to SP-SHR.
This research was supported by Grant Nos. HL14388 and HL16328 from the National Institutes of Health. Dr. Rusch is the recipient
of Postdoctoral Fellowship HL06907. 相似文献