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91.
Pekka Löppönen Sami Tetri Seppo Juvela Juha Huhtakangas Pertti Saloheimo Michaela K. Bode John Koivukangas Matti Hillbom 《Clinical neurology and neurosurgery》2013
Background and Purpose
The role of surgery after primary intracerebral hemorrhage (ICH) is controversial. To explore whether hematoma evacuation after ICH had improved short-term survival or functional outcome we conducted a retrospective observational population-based study.Methods
We identified all subjects with primary ICH between 1993 and 2008 among the population of Northern Ostrobothnia, Finland. Hematoma evacuation was carried out by using standard craniotomy or through a burr hole. We compared mortality rates and functional outcomes of patients with hematoma evacuation with those treated conservatively.Results
Of 982 patients with verified ICH during the study period, 127 (13%) underwent hematoma evacuation. Surgically treated patients were significantly younger (mean ± SD, 63 ± 11 vs. 70 ± 12 years; p < 0.001), had larger hematomas (66 ± 36 vs. 28 ± 40 ml; p < 0.001), lower Glasgow Coma Scale scores (median, 11 vs. 14; p < 0.001) and more frequently subcortical hematomas (68% vs. 24%; p < 0.001) than those treated conservatively. In multivariable analysis, hematoma evacuation independently lowered 3-month mortality (adjusted hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.43–0.88; p < 0.03), particularly among patients aged ≤70 years with ≥30 ml supratentorial hematomas (adjusted HR, 0.26; 95% CI, 0.14–0.49; p < 0.001). However, poor outcome was not improved by surgery (adjusted odds ratio 0.71; 95% CI 0.29–1.70).Conclusions
Improved 3-month survival was observed in patients who had undergone hematoma evacuation relative to patients not undergoing evacuation particularly in the subgroup of patients aged ≤70 years with ≥30 ml supratentorial hematomas. Surgery might improve outcome if cases could be selected more precisely and if performed before deterioration. 相似文献92.
93.
Do Diuretics have Antinociceptive Actions: Studies of Spironolactone,Eplerenone, Furosemide and Chlorothiazide,Individually and with Oxycodone and Morphine
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Viljami Jokinen Tuomas Lilius Jouko Laitila Mikko Niemi Oleg Kambur Eija Kalso Pekka Rauhala 《Basic & clinical pharmacology & toxicology》2017,120(1):38-45
Spironolactone, eplerenone, chlorothiazide and furosemide are diuretics that have been suggested to have antinociceptive properties, for example via mineralocorticoid receptor antagonism. In co‐administration, diuretics might enhance the antinociceptive effect of opioids via pharmacodynamic and pharmacokinetic mechanisms. Effects of spironolactone (100 mg/kg, i.p.), eplerenone (100 mg/kg, i.p.), chlorothiazide (50 mg/kg, i.p.) and furosemide (100 mg/kg, i.p.) were studied on acute oxycodone (0.75 mg/kg, s.c.)‐ and morphine (3 mg/kg, s.c.)‐induced antinociception using tail‐flick and hot plate tests in male Sprague Dawley rats. The diuretics were administered 30 min. before the opioids, and behavioural tests were performed 30 and 90 min. after the opioids. Concentrations of oxycodone, morphine and their major metabolites in plasma and brain were quantified by mass spectrometry. In the hot plate test at 30 and 90 min., spironolactone significantly enhanced the antinociceptive effect (% of maximum possible effect) of oxycodone from 10% to 78% and from 0% to 50%, respectively, and that of morphine from 12% to 73% and from 4% to 83%, respectively. The brain oxycodone and morphine concentrations were significantly increased at 30 min. (oxycodone, 46%) and at 90 min. (morphine, 190%). We did not detect any independent antinociceptive effects with the diuretics. Eplerenone and chlorothiazide did not enhance the antinociceptive effect of either opioid. The results suggest that spironolactone enhances the antinociceptive effect of both oxycodone and morphine by increasing their concentrations in the central nervous system. 相似文献
94.
Patient‐specific pharmacokinetic parameter estimation on dynamic contrast‐enhanced MRI of prostate: Preliminary evaluation of a novel AIF‐free estimation method
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95.
Bravin A Keyriläinen J Fernández M Fiedler S Nemoz C Karjalainen-Lindsberg ML Tenhunen M Virkkunen P Leidenius M von Smitten K Sipilä P Suortti P 《Physics in medicine and biology》2007,52(8):2197-2211
The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources. 相似文献
96.
Anne Tammimäki Anu Aonurm-Helm Pekka T. Männistö 《Xenobiotica; the fate of foreign compounds in biological systems》2018,48(4):325-331
1.?Catechol-O-methyltransferase (COMT) is involved in the O-methylation of l-DOPA, dopamine, and other catechols. The enzyme is expressed in two isoforms: soluble (S-COMT), which resides in the cytoplasm, and membrane-bound (MB-COMT), which is anchored to intracellular membranes.2.?To obtain specific information on the functions of COMT isoforms, we studied how a complete MB-COMT deficiency affects the total COMT activity in the body, peripheral l-DOPA levels, and metabolism after l-DOPA (10?mg kg?1) plus carbidopa (30?mg kg?1) administration by gastric tube in wild-type (WT) and MB-COMT-deficient mice. l-DOPA and 3-O-methyl-l-DOPA (3-OMD) levels were assayed in plasma, duodenum, and liver.3.?We showed that the selective lack of MB-COMT did not alter the total COMT activity, COMT enzyme kinetics, l-DOPA levels, or the total O-methylation of l-DOPA but delayed production of 3-OMD in plasma and peripheral tissues. 相似文献
97.
Maarit Jaana Korhonen Pekka Tiittanen Helena Kastarinen Arja Helin‐Salmivaara Milka Hauta‐aho Maria Rikala Risto Huupponen 《Basic & clinical pharmacology & toxicology》2018,123(2):195-201
Clinical significance of potential interaction between warfarin and statins is unclear. Our objective was to determine whether use of statins as a class or use of simvastatin modulates the rate of bleeding requiring hospitalization among new warfarin users. Using Finnish healthcare databases, we identified a cohort of 101,588 warfarin initiators between 1 January 2009 and 30 June 2012. By the end of 2012, these patients accumulated 92,695 person‐years of exposure to warfarin‐only and 60,253 years of exposure to warfarin‐with‐statin. The outcome was a composite of gastrointestinal, intracranial or other bleeding leading to hospitalization. A Poisson generalized estimating equation model was employed to estimate rate ratios (RR) and their 95% confidence intervals (CI) for exposure to warfarin‐with‐statin compared to warfarin‐only and to allow multiple episodes per patient and time‐dependent covariates. In multivariable models, we found no difference in the bleeding rate in association with exposure to any statin (multivariable‐adjusted RR = 0.98, 95% CI 0.89–1.07) or to simvastatin (RR = 1.01, 95% CI 0.91–1.11) with warfarin compared to exposure to warfarin‐only. We conclude that concomitant use of statins and warfarin was not associated with an increased rate of bleeding requiring hospitalization. 相似文献
98.
99.
Jani Rankinen Petri Haataja LeoPekka Lyytikinen Heini Huhtala Terho Lehtimki Mika Khnen Markku Eskola Andrs Ricardo PrezRiera Antti Jula Harri Rissanen Kjell Nikus Jussi Hernesniemi 《Annals of noninvasive electrocardiology》2021,26(1)
BackgroundPrevious population studies have presented conflicting results regarding the prognostic impact of intraventricular conduction delays (IVCD).MethodsWe studied long‐term prognostic impact and the association with comorbidities of eight IVCDs in a random sample of 6,299 Finnish subjects (2,857 men and 3,442 women, mean age 52.8, SD 14.9 years) aged 30 or over who participated in the health examination including 12‐lead ECG. For left bundle branch block (LBBB) and non‐specific IVCD (NSIVCD), two different definitions were used.ResultsDuring 16.5 years’ follow‐up, 1,309 of the 6,299 subjects (20.8%) died and of these 655 (10.4%) were cardiovascular (CV) deaths. After controlling for known clinical risk factors, the hazard ratio for CV death, compared with individuals without IVCD, was 1.55 for the Minnesota definition of LBBB (95% confidence interval 1.04–2.31, p = .032) and 1.27 (95% confidence interval 0.80–2.02, p = .308) for the Strauss’ definition of LBBB. Subjects with NSIVCD were associated with twofold to threefold increase in CV mortality depending on the definition. While right bundle branch block, left anterior fascicular block and incomplete bundle branch blocks were associated with seemingly higher mortality, this was no longer the case after adjustment for age and sex. The presence of R‐R’ pattern was not associated with any adverse outcome.ConclusionsIn a population study with long‐term follow‐up, NSIVCD and Minnesota definition of LBBB were independently associated with CV mortality. Other IVCDs had no significant impact on prognosis. The prognostic impact of LBBB and NSIVCD was affected by the definition of the conduction disorder. 相似文献
100.
Maria Francesca Sfondrini Simone Gallo Benedetta Turcato Mona A. Montasser Nehal Fouad Albelasy Pekka K. Vallittu Paola Gandini Andrea Scribante 《Materials》2021,14(6)
This study aims to assess the efficacy of a universal adhesive (Scotchbond Universal, 3M ESPE) (SB) in total-etch mode, compared to a traditional orthodontic primer (Transbond XT Primer, 3M ESPE) (XT Primer), to perform bonding of orthodontic fixed retainers along with the Transbond XT Light Cure Adhesive Paste (3M ESPE). For the in vitro study, a round section wire (Ortosmail Krugg) was bonded using XT Primer for 20 bovine incisors (Group 1) and SB for other 20 (Group 2). Samples were debonded in a universal testing machine applying a tangential force to specimens (crosshead speed of 1 millimeter per minute). Shear bond strength (SBS) and adhesive remnant index (ARI) scores were calculated. For the in vivo study, 100 patients needing upper and lower canine-to-canine fixed retainers after orthodontic treatment were randomly assigned to two groups of 50 participants each, i.e., group 1 (retainer bonding with XT Primer) and group 2 (retainer bonding with SB). Over two years, examinations were carried out monthly, and detachments were registered by considering the teeth and arches affected. In vitro, no statistically significant differences in SBS and ARI scores were demonstrated between the two groups, both showing a mean bond strength of about 12 MPa and major frequency of ARI “2” (>50% remnant adhesive on the enamel). Conversely, a significantly lower failure rate over 2 years was assessed clinically for group 2 in both arches. Independently of the adhesive and arch, incisors reported a significantly higher failure rate than canines. Scotchbond Universal used in total-etch mode could be a valid alternative to the traditional orthodontic Transbond XT Primer. 相似文献