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Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
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In a nonimmunocompromised patient with cerebral cryptococcosis, unique magnetic resonance findings included abnormalities limited to the posterior fossa and cerebellar hemispheric edema, gyriform enhancement of the vermis and cerebellar hemispheres, and infratentorial plaquelike enhancement. Magnetic resonance findings in central nervous system cryptococcosis are discussed. 相似文献
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Thor S. Trovik Aase Vaartun Georg Sager 《Basic & clinical pharmacology & toxicology》1995,77(4):270-275
Abstract: Loss of adrenergic hypoglycaemic symptoms is the most distinctive feature in insulin-dependent diabetes mellitus (IDDM) patients with hypoglycaemia unawareness. Previous reports from in vivo studies show reduced heart rate responsiveness both to adrenergic agonists and antagonists in these patients. This study was carried out to investigate whether the reduced adrenergic sensitivity in IDDM patients with hypoglycaemia unawareness (IDDM-unaware) also could be demonstrated as reduced increase in cAMP production in mononuclear leucocytes induced by isoprenaline stimulation, or reduced inhibition by ICI-118551 (a selective β2-adrenergic receptor blocker) of isoprenaline induced cAMP production. We found that the slope of the concentration-response curves of isoprenaline/cAMP and the maximal cAMP concentrations obtained after isoprenaline stimulation were reduced in IDDM-unaware compared to control and IDDM patients with normal hypoglycaemia awareness (IDDM-aware). We did not find any significant differences in the response to ICI-118551 between control, IDDM-aware and IDDM-unaware. This study supports the reports of reduced sensitivity of adrenergic agonists as a part of the pathophysiological changes in hypoglycaemia unawareness, but we have not been able to confirm the reports of an association between hypoglycaemia unawareness and reduced effect of adrenergic antagonists. 相似文献
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M. Sääf M. Thorén C. -G. Bergstrand G. Norén T. Rähn L. Tallstedt E. -O. Backlund 《Acta neurochirurgica》1989,99(3-4):97-103
Summary Fourty-two consecutive patients with craniopharyngioma were treated by stereotactic approach, i.e. preferentially stereotactic puncture and installation of colloid isotope into cystic tumours and external stereotactic single dose irradiation to solid tumour parts. In a minority of cases, such treatment was less suitable, and surgical removal and/or radiotherapy was used. There was no peroperative mortality. A long-term follow up (observation time 10–23 years) of the 31 patients alive indicated that they were socially well adapted with a high rate of fulltime work and a low rate of intercurrent disease. In spite of substitution therapy for pituitary insufficiency in most cases, the patients were subjectively seldom disturbed by their disease.Our results support a change in the choice of therapy for craniopharyngioma patients, from open neurosurgery to the less invasive stereotactic techniques. 相似文献
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Geographical and temporal conservation of antibody recognition of Plasmodium falciparum variant surface antigens 下载免费PDF全文
Nielsen MA Vestergaard LS Lusingu J Kurtzhals JA Giha HA Grevstad B Goka BQ Lemnge MM Jensen JB Akanmori BD Theander TG Staalsoe T Hviid L 《Infection and immunity》2004,72(6):3531-3535
The slow acquisition of protection against Plasmodium falciparum malaria probably reflects the extensive diversity of important antigens. The variant surface antigens (VSA) that mediate parasite adhesion to a range of host molecules are regarded as important targets of acquired protective immunity, but their diversity makes them questionable vaccine candidates. We determined levels of VSA-specific immunoglobulin G (IgG) in human plasma collected at four geographically distant and epidemiologically distinct localities with specificity for VSA expressed by P. falciparum isolates from three African countries. Plasma levels of VSA-specific IgG recognizing individual parasite isolates depended on the transmission intensity at the site of plasma collection but were largely independent of the geographical origin of the parasites. The total repertoire of immunologically distinct VSA thus appears to be finite and geographically conserved, most likely due to functional constraints. Furthermore, plasma samples frequently had high IgG reactivity to VSA expressed by parasites isolated more than 10 years later, showing that the repertoire is also temporally stable. Parasites from patients with severe malaria expressed VSA (VSASM) that were better recognized by plasma IgG than VSA expressed by other parasites, but importantly, VSASM-type antigens also appeared to show substantial antigenic homogeneity. Our finding that the repertoire of immunologically distinct VSA in general, and in particular that of VSASM, is geographically and temporally conserved raises hopes for the feasibility of developing VSA-based vaccines specifically designed to accelerate naturally acquired immunity, thereby enhancing protection against severe and life-threatening P. falciparum malaria. 相似文献