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61.
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Lamiya Samad Chris Hollis Martin Prince Robert Goodman 《International journal of methods in psychiatric research》2005,14(4):230-230
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
63.
Martin Williams 《Transfusion and apheresis science》2007,36(2):213-214
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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
68.
Martin Tepel 《Nephrology, dialysis, transplantation》2003,18(8):1439-1442
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 12% 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
69.
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
70.
Margaretha Jennerwein Ronald Gust Richard Müller Helmut Schnenberger Jürgen Engel Martin R. Berger Dietrich Schmhl Siegfried Seeber Reinhanidt Osieka Ghanem Atassi Danile Marchal-De Bock 《Archiv der Pharmazie》1989,322(2):67-73
The activity of stereoisomeric [1,2-bis(3-hydroxyphenyl)ethylenediamine] dichloroplatinum(II)-complexes (1-PtCl2,R,S; 2-PtCl2, R,R/S,S; 3-PtCl2, R,R; 4-PtCl2, S,S) on several tumor models (MDA-MB 231 breast cancer cell line; P 388 leukemia, mouse; L 1210 leukemia, mouse; L 5222 leukemia, rat; Ehrlich ascites tumor, mouse--wildtype; cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.) is described. For comparison the analogous [1,2-bis(4-hydroxyphenyl)ethylendiamine]dichloroplatinum (II)-complexes (5-PtCl2, R, S; 6-PtCl2, R,R/S,S; 7-PtCl2, R,R; 8-PtCl2, S,S) and cisplatin are used. 1-PtCl2 to 4-PtCl2 (OH in 3,3'-positions) show their maximum antitumor effect at lower doses than 5-PtCl2 to 8-PtCl2 (OH in 4,4'-positions). 2-PtCl2 and 6-PtCl2 (R,R/S,S) are more active than 1-PtCl2 and 5-PtCl2 (R,S). 4-PtCl2 and 8-PtCl2 (S,S) are superior to 3-PtCl2 and 7-PtCl2 (R,R). On the L 5222 leukemia 2-PtCl2 (R,R/S,S), 4-PtCl2 (S,S) and 8-PtCl2 (S,S) markedly surpass cisplatin. Strong effects are produced by 2-PtCl2 to 4-PtCl2 on the Ehrlich ascites tumor (wildtype, cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.). The combination of 4-PtCl2 with cisplatin results in a weakly synergistic effect. 相似文献