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The original article to which this Erratum refers was published in International Journal of Methods in Psychiatric Research, 2005; Vol.14, No.3, 158–166. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Objectives: To investigate the effect of the type instrumentation used and the age and gender characteristics of patients on postoperative haemorrhage rates following tonsil and adenoid surgery. Design: A retrospective analysis of 13 593 procedures was performed from The Patient Episode Database for Wales between 1 January 1999 and 31 March 2004. Setting: National health policy changes created four periods of different instrument usage (reusable, single‐use with diathermy, single‐use alone, specified single‐use with diathermy). These and the age and gender distribution of the patients were examined against four categories of postoperative haemorrhage. Main outcome measures: Postoperative haemorrhage rates were expressed as the number of complications per operations performed. Primary postoperative haemorrhage that occurred during the initial admission either required a return to theatre [R1] or was managed conservatively [N1]; secondary postoperative haemorrhage that required a return to hospital either returned to theatre [R2] or was managed conservatively [N2], were compared. Results: Primary haemorrhage with return to theatre doubled, from the baseline rate with reusable instruments, from 0.6% (CI 0.5–0.8) to 1.2% (CI 0.7–1.9) when single‐use instruments were introduced and remained high at 1.4% (CI 0.9–2.1) after the withdrawal of single‐use diathermy. This haemorrhage rate returned to the baseline rate (0.6% CI 0.3–1.0) when specified single‐use instruments were introduced. None of the other haemorrhage rates changed significantly throughout the four observation periods. Adenotonsillectomy and tonsillectomy patients have different age and gender patterns. In a univariate analysis, males over the age of 12 years were twice as likely to have haemorrhage with return to theatre than girls of the same age, 3.8% (CI 3.0–4.7) versus 1.7% (CI 1.4–2.1). Conclusions: A significant rise in serious postoperative primary haemorrhage but not secondary haemorrhage was seen following the initial introduction of single‐use instruments that reverted to baseline with the introduction of specified single‐use instruments. Diathermy does not appear to have affected the haemorrhage rates. There is a distinct age and gender pattern for tonsil and adenoid surgery and risk of postoperative haemorrhage. The use of arbitrary divisions of age may be misleading in studies that examine post‐tonsillectomy haemorrhage.  相似文献   
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Reactive oxygen species: general aspects Reactive oxygen species, including superoxide radicals, hydrogenperoxide, nitric oxide, peroxynitrite, hydroxyl radicals andhypochlorous acid are by-products of normal metabolic processesin cells. Reactive oxygen species can be found in several cellsincluding macrophages and vascular smooth muscle cells. At lowconcentrations reactive oxygen species can act as physiologicalmediators of cellular responses whereas higher concentrationsmay cause cell damage [1,2]. The major sources of reactive oxygenspecies are leakages from the electron transport chains of mitochondriaand endoplasmic reticulum. Cellular energy metabolism is basedon the production of ATP through the electron transport reactionin which O2 accepts electrons and H+ and then is eventuallyreduced to water. Only 1–2% of the electrons are leakedto generate superoxide radicals in reactions mediated by coenzymeQ and ubiquinone and its complexes. During ageing (and probablyin patients  相似文献   
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The regioselective reaction of aliphatic ω-isocyanatoacyl chlorides with silyl-protected hydroxy-nucleophiles was extended to aromatic isocyanatoacyl chlorides. Starting with 3- or 4-isocyanatobenzoyl chloride and 3- or 4-trimethylsiloxyphenyl isocyanate, the four isomeric isocyanatobenzoic acid isocyanatophenyl esters were synthesized in high yields. From terephthaloyl chloride and two moles of a siloxyphenyl isocyanate or from 1,4-bis(trimethylsiloxybenzene) and two moles of an isocyanatobenzoyl chloride, diesterdiisocyanates were obtained containing 3 benzene rings. The para-substituted diisocyanates show liquid-crystalline behaviour. Polyaddition reaction with various diols led to poly(esterurethane)s with a regular sequence of urethane and ester groups. The poly(urethane)s from the para-substituted diisocyanates have very high melting points (225–350°C). Liquid crystallinity could not be proven unambiguously due to the instability of the urethane linkage at these temperatures.  相似文献   
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Thyrotropin releasing hormone (TRH) was administered intravenously to ten patients with Alzheimer's Disease (AD) in a high-dose paradigm, thought to maximize central nervous system effects and potentially produce facilitation of cholinergic function, a known property of the neuropeptide. Acute effects of TRH on behavioral, cognitive and physiologic measures were assessed after patients received 0.1 mg/kg TRH, 0.3 mg/kg TRH and placebo, the higher TRH dose and placebo being given in a randomized, double-blind fashion. Patients showed statistically significant increases in arousal and improvement in affect, as well as a modest improvement in semantic memory, all after receiving the higher TRH dose. Both TRH doses produced transient rises in systolic blood pressure, with no effect on diastolic blood pressure, heart rate or temperature. This study suggests that high-dose TRH can be safely administered to AD patients and is neurobehaviorally active; further studies are needed to determine the extent and mechanism of the cognitive and psychobiological properties of this peptide in AD and other neuropsychiatric disorders.  相似文献   
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