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921.
922.
923.
Frans F. Jöbsis-VanderVliet Claude A. Piantadosi Avis L. Sylvia Stephen K. Lucas Hans H. Keizer 《Neurological research》2013,35(1):7-17
Near-infrared (NIR) difference spectra were obtained for oxidized cytochrome c oxidase of isolated mitochondria in vitro and of cerebral tissue in situ observed through scalp and skull. The broad peaks of maximal absorption observed in both were not inconsistent with the customary assignment of an 830 nm peak. However, the ratios of the intensity of the NIR band to that of the visible peak (605 nm), which we found to be identical for in-vitro and in-situ spectra, were consistently and significantly higher than those of the various purified enzyme preparations reported in the literature. In addition the half-band widths of our in-vitro and in-situ preparations were narrower. Haemoglobin spectra in the NIR obtained in clear and in highly light-scattering media showed almost total absence of band distortion in this spectral region, suggesting that the differences observed are not due to scattering effects. Anoxia and the specific oxidase inhibitors, cyanide and carbon monoxide, caused the expected disappearance of the band in both the mitochondria in vitro and the cerebrum in situ. The 830 nm band observed in intact, well-oxygenated animal preparations was therefore identified with the NIR absorption band of oxidized cytochrome c oxidase, notwithstanding the differences with the observations on purified preparations. This points to the possibility of developing instrumentation and techniques for the non-invasive monitoring of the redox state of cytochrome c oxidase as an index to cerebral oxygen sufficiency, i.e. adequate delivery and utilization of oxygen to and by brain tissue. 相似文献
924.
Evert de Jonge Linda Peelen Peter J Keijzers Hans Joore Dylan de Lange Peter HJ van der Voort Robert J Bosman Ruud AL de Waal Ronald Wesselink Nicolette F de Keizer 《Critical care (London, England)》2008,12(6):R156-8
Introduction
The aim of this study was to investigate whether in-hospital mortality was associated with the administered fraction of oxygen in inspired air (FiO2) and achieved arterial partial pressure of oxygen (PaO2).Methods
This was a retrospective, observational study on data from the first 24 h after admission from 36,307 consecutive patients admitted to 50 Dutch intensive care units (ICUs) and treated with mechanical ventilation. Oxygenation data from all admission days were analysed in a subset of 3,322 patients in 5 ICUs.Results
Mean PaO2 and FiO2 in the first 24 h after ICU admission were 13.2 kPa (standard deviation (SD) 6.5) and 50% (SD 20%) respectively. Mean PaO2 and FiO2 from all admission days were 12.4 kPa (SD 5.5) and 53% (SD 18). Focusing on oxygenation in the first 24 h of admission, in-hospital mortality was shown to be linearly related to FiO2 value and had a U-shaped relationship with PaO2 (both lower and higher PaO2 values were associated with a higher mortality), independent of each other and of Simplified Acute Physiology Score (SAPS) II, age, admission type, reduced Glasgow Coma Scale (GCS) score, and individual ICU. Focusing on the entire ICU stay, in-hospital mortality was independently associated with mean FiO2 during ICU stay and with the lower two quintiles of mean PaO2 value during ICU stay.Conclusions
Actually achieved PaO2 values in ICU patients in The Netherlands are higher than generally recommended in the literature. High FiO2, and both low PaO2 and high PaO2 in the first 24 h after admission are independently associated with in-hospital mortality in ICU patients. Future research should study whether this association is causal or merely a reflection of differences in severity of illness insufficiently corrected for in the multivariate analysis. 相似文献925.
926.
We describe three cases in whom identification of a disease-causing mutation in the TSC1 or TSC2 gene preceded the appearance or detection of symptoms sufficient for a clinical diagnosis of tuberous sclerosis complex (TSC). We suggest that genetic testing be given a more prominent role in the evaluation of individuals with a family history of TSC or symptoms suggestive of TSC and propose that diagnostic criteria be revised to include genetic testing. 相似文献
927.
928.
Serum zinc levels were studied in 75 patients of different cutaneous disorders and 24 healthy controls. It was found to be significantly lower in acne vulgaris (71.5 ± 21.5µgm/100ml), leprosy(85.9 ± 26.9µgm/100ml) and psoriasis (93.3 ± 25.9µgm/100ml) as compared to healthy controls (105.3 ± 30.1µgm/100ml). No significant correlation was found in other cutaneous disorders studied i.e. vitiligo and aphthous ulcers where serum zinc levels were found to be 97.3 ± 26.6 µgm/100ml and 105.2 ± 23.5 µgm/100ml respectively.Key Words: Acne vulgaris, Aphthous ulcers, Leprosy, Psoriasis, Vitiligo, Zinc 相似文献
929.
930.
ZUHAIR N. AL‐HASSNAN SAHAR TULBAH WALEED AL‐MANEA MAJID AL‐FAYYADH 《Pacing and clinical electrophysiology : PACE》2013,36(5):e140-e142
Catecholaminergic polymorphic ventricular tachycardia (CPVT) manifests with episodic syncope or sudden death in young patients following physical activity or emotional stress. The autosomal recessive form of CPVT is caused by mutations in the CASQ2 gene. In a consanguineous family, a novel homozygous CASQ2 mutation (p.L77P) was identified in a child with CPVT who required implantation of a cardioverter defibrillator due to episodes of syncope while on medical therapy. Genetic testing found the younger sibling, who had normal initial clinical screening, to be affected. Our cases underscore the importance of family screening through genetic testing to preemptively apply the appropriate medical intervention in CPVT. (PACE 2013; 36:e140–e142) 相似文献