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961.
Hyperaemia prior to acute cerebral swelling in severe head injuries: The role of transcranial doppler monitoring 总被引:4,自引:0,他引:4
Z. Muttaqin M.D. T. Uozumi S. Kuwabara K. Arita K. Kurisu S. Ohba H. Kohno H. Ogasawara M. Ohtani T. Mikami 《Acta neurochirurgica》1993,123(1-2):76-81
Summary Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement, transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral haemodynamics, including hyperaemic conditions.TCD examinations was serially performed in 35 patients with severe head injury with intact cerebral circulation; i.e. the mean flow velocity (MFV) patterns of the middle cerebral artery (MCA) did not show signs of cerebral circulatory arrest such as systolic spike, to and fro, or no flow. The results showed that the MFV of the MCAs and ipsilateral extracranial internal carotid arteries (ICAs) in 9 of these patients increased sharply and pulsatility index (PI) decreased during 48–96 hours after the injury. This was soon followed by patterns of high intracranial resistance, consistent with elevated intracranial pressure (ICP) in monitored patients and acute brain swelling on repeated computed tomographic (CT) scans. The correlation between increased MFVs, decreased PIs, and cerebral haemodynamic changes leading to acute brain swelling is discussed.The number of patients who ended with severe disability, vegetative state, or death was 66% in this group of 9 patients, compared to only 34% for the 35 patients overall with severe head injury. Though the morbidity and mortality rates largely depend on the primary injury, the presence of acute cerebral swelling aggravate the grave course in these patients. And the ability of TCD to monitor the hyperaemic state prior to oedema should lead us to adjust the therapy in order to minimize the secondary insult related to intracranial hypertension. 相似文献
962.
963.
B S Polinkevich M P Koval'ski? S D Gro?sman 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1990,(8):24-26
In dogs, only fundus and body, or antrum were denervated. At the period of up to 5 years after vagotomy, no complete parasympathetic reinnervation of the stomach occurs. 相似文献
964.
Minimal inhibitory concentrations (MICs) of the oral cephalosporin BAY v 3522, and of cephprozyl, cefaclor, cefixime, cefuroxime, cefetamet, cefpodoxime and cefotaxime were determined against Gram-positive and Gram-negative clinical isolates with the NCCLS agar dilution procedures. BAY was the most active drug against Gram-positive organisms. MICs ranged from 0.01 mg/l against group A streptococci to 16 mg/l against S. faecium. Although mean MICs of BAY against methicillin-resistant S. aureus and S. epidermidis were between 0.9-1.8 mg/l, respectively, such strains showed typical heteroresistance in population studies. In addition, the biochemical correlate of methicillin-resistance, the PBP-2', showed similar low affinity to BAY as methicillin. beta-lactamase-producing H. influenzae and B. catarrhalis were inhibited by 2-8 and 0.25-2 mg/l, respectively, whereas non-producers were inhibited by 0.25-2 and 0.12-1 mg/l of the drug. The activity of BAY against enterobacteriaceae was rather low. Ampicillin-susceptible E. coli strains were inhibited by 2-8 and resistant strains by 8-32 mg/l. The mean MIC against cephalothin-susceptible K. pneumoniae strains was 2.8, and that against resistant strains 27.4 mg/l. MICs against beta-lactamase-producing enterobacteriaceae determined in broth dilution were 4-8 times higher than those determined in agar dilution. Bactericidal activity was measured in killing-curve experiments at 4 times the MIC. BAY killed equally well as standard control drugs. 相似文献
965.
A peer tutorial programme which is available to all first- and second-year medical students has been in operation at Case Western Reserve University School of Medicine since 1972. A retrospective study of the classes of 1982, 1983 and 1984 was undertaken to assess the participation levels in the tutorial programme and to compare the participation level to available performance parameters. The analysis revealed that 54% of the first-year classes and 22% of the second-year classes participated in the peer tutorial programme. X2 analysis of the data demonstrated that the relationship between participation in the tutorial programme and performance on examinations reached statistical significance. The results suggested that an open peer tutorial programme responded to the needs, both cognitive and affective, of medical students. 相似文献
966.
M R?sener J Dichgans R Martin F Harms 《Journal of neurology, neurosurgery, and psychiatry》1995,58(5):637-638
967.
Role of endothelin in the pathogenesis of hypertension in spontaneously hypertensive and 2 kidneys 1 clip rats. 总被引:1,自引:0,他引:1
The plasma endothelin (ET) level in spontaneously hypertensive rats (SHR) and 2K1C hypertension animal models and its vasoconstrictive effect on renal and tail arteries were studied. The results demonstrated that there was no difference in plasma ET level between the hypertensive groups SHR, 2K1C, normotensive control groups Wistar Kyot (WKY) and Sprague Dawley (SD), while the vasoconstrictive effect of ET in SHR was more dominant than in WKY. The EC50 of the renal and tail arteries in SHR (0.8912 +/- 0.1662 x 10(-8) M, 0.6103 +/- 0.0878 x 10(-8) M) was apparently lower than that in WKY (1.77 +/- 0.2991 x 10(-8) M, 1.2267 +/- 0.2502 x 10(-8) M, P less than 0.05), but no difference was found in 2K1C and SD rats. The four groups of animals exhibited no difference of such effects as response to norepine-phrine (NA). The findings suggested that the increased arteriole sensitivity to ET be an important factor in the pathogenesis of hypertension in SHR.
相似文献
968.
969.
970.
作者应用电子自旋共振技术(ESR)分别对正常人、口腔颌面部良恶性肿瘤、口腔粘膜病患者共324例的头发进行自由基测定,并与病理诊断相对照。结果表明,它们的阳性率分别为5.9%,6.1%,84.52%及9.1%。其中恶性肿瘤与正常人及良性肿瘤相比较,差别均较显著(P<0.01)。部分恶性肿瘤患者经治疗后,ESR饱和功率点后移,上升到临界水准以上(>10.0mW),ESR转阴。表明用ESR早期诊断恶性肿瘤、追踪疗效具有一定临床价值。作者还结合检测资料对ESR在监测肿瘤复发、监视白斑癌变等方面的意义进行了讨论。 相似文献