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41.
Patricio Melean MD Markus Loew MD PhD Petra Magosch MD Stephan Riedmann MD Peter Habermeyer MD PhD Patric Raiss MD 《Obere Extremit?t》2014,9(1):45-50
Background
The objective of this study was to analyze proximal humeral geometry in two groups of patients with posttraumatic fracture sequelae who were treated with either resurfacing (R) or stemless (S) arthroplasty. The hypothesis was that there is no difference in the radiographic restoration of postoperative proximal humeral geometry after resurfacing or stemless arthroplasties.Material and methods
A match-paired analysis of 48 cases was completed (R?=?24, S?=?24). Proximal geometry was assessed reviewing true anterior–posterior x-rays, measuring the inclination angle of osteotomy (IAO), distance above tuberosity (DAT), superior humeral translation (SHT) according to Torchia, medial offset (MO), and lateral offset (LO).Results
The average follow-up was 32.4?±?9.2 months for group R and 37.9?±?22.9 months for group S (p?=?0.317). Except for MO and SHT, no significant differences were found. Restoration of the anatomical MO was more accurate for group S. SHT of the humerus was detected more frequently for group R.Conclusions
In this match-paired analysis, stemless arthroplasty reconstructed an anatomic MO more consistently than resurfacing arthroplasty as evaluated on x-rays; we did not document differences in the remaining evaluated parameters. However, no significant differences were found between both groups regarding clinical outcomes. 相似文献42.
Slovenian population data for five new European Standard Set Short tandem repeat loci and SE33 locus
Irena Zupani? Pajni? Eva Podov?ovnik Axelsson Jo?e Bala?ic 《Croatian medical journal》2014,55(1):14-18
Aim
To establish the allele distribution and statistical parameters of forensic interest for the D10S1248, D22S1045, D2S441, D1S1656, D12S391, and SE33 loci in Slovenian population and to compare allele frequencies with those from other populations.Methods
We analyzed blood and buccal swab samples from 333 unrelated, healthy Slovenian individuals. All samples were genotyped using the AmpFlSTR NGM Kit to obtain the allele frequency data for the loci D10S1248, D22S1045, D2S441, D1S1656, and D12S391. Samples from 113 individuals were also analyzed using the PowerPlex ESX 17 system to obtain the allele frequency data for the SE33 locus. Allele frequencies and statistical parameters of forensic interest were determined and frequency profiles compared between Slovenian and other European Caucasian populations using the Arlequin software, version 3.5.1.3.Results
The investigated short tandem repeat (STR) loci in Slovenian population had a great discriminating potential with a combined discrimination power of 0.99999998. The highest discrimination power and polymorphism information content were observed for the SE33 locus, followed by loci D1S1656, D12S391, D10S1248, D2S441, and D22S1045. When Slovenian allele frequency distribution was compared with other European populations, deviations were found only for Spanish and Italian population for D2S441 and D12S391.Conclusion
Slovenian population does not differ significantly from other European populations in terms of allele frequency distributions for the six analyzed STR loci. Based on forensic efficiency values, SE33 may be considered the most informative locus, which makes it especially useful in forensic investigations.In their recommendations for autosomal short tandem repeat (STR) DNA typing in forensic casework, the European Network of Forensic Institutes (ENFSI) and the European DNA Profiling (EDNAP) Group proposed the use of additional five STRs, three mini-STRs (D2S441, D10S1248, D22S1045), and two highly polymorphic STRs (D1S1656 and D12S391). The increased number of the European Standard Set (ESS) loci resulted in improved discrimination power, sensitivity, and reproducibility for the analysis of minute amounts of DNA (1,2). In the last few years, several commercial STR typing kits have been released, with five new ESS loci. The new kits have been shown to be robust enough to successfully genotype even degraded DNA from old bone material (3-5). These kits also include the AmpFlSTR NGMTM PCR Amplification Kit (Applied Biosystems, Foster City, CA, USA) and the PowerPlex ESX 17 System (Promega, Madison, WI, USA), which we used for our population study. Allele frequencies for autosomal STRs (6,7), Y-chromosomal STRs (8), and mitochondrial DNA (9) were already determined for Slovenian population and the aim of this study was to apply new genetic markers in routine forensic casework to achieve higher evidential value of STR typing and to increase the number of short STR loci, which are better preserved in degraded samples. Some European population studies have already investigated the new ESS loci (D10S1248, D22S1045, D2S441, D1S1656, D12S391) and we compared Slovenian allele frequencies with them (10-17). Beside the analysis of 5 new ESS loci we also analyzed SE33 locus and compared allele frequencies with Austrian (15), Italian (16), German (18), and Spanish population (19). 相似文献43.
Johannes Boos Patric Kröpil Dirk Klee Philipp Heusch Lars Schimmöller Jörg Schaper Gerald Antoch Rotem S. Lanzman 《Pediatric radiology》2014,44(9):1065-1069
Background
Organ-specific dose reduction significantly reduces the radiation exposure of radiosensitive organs.Objective
The purpose of this study was to assess the impact of a novel organ-specific dose reduction algorithm on image quality of pediatric chest CT.Materials and methods
We included 28 children (mean age 10.9?±?4.8 years, range 3–18 years) who had contrast-enhanced chest CT on a 128-row scanner. CT was performed at 100 kV using automated tube current modulation and a novel organ-specific dose-reduction algorithm (XCare?; Siemens, Forchheim, Germany). Seven children had a previous chest CT performed on a 64-row scanner at 100 kV without organ-specific dose reduction. Subjective image quality was assessed using a five-point scale (1-not diagnostic; 5-excellent). Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were assessed in the descending aorta.Results
Overall mean subjective image quality was 4.1?±?0.6. In the subgroup of the seven children examined both with and without organ-specific dose reduction, subjective image quality was comparable (score 4.4?±?0.5 with organ-specific dose reduction vs. 4.4?±?0.7 without it; P?>?0.05). There was no significant difference in mean signal-to-noise ratio and contrast-to-noise ratio with organ-specific dose reduction (38.3?±?10.1 and 28.5?±?8.7, respectively) and without the reduction (35.5?±?8.5 and 26.5?±?7.8, respectively) (P?>?0.05). Volume computed tomography dose index (CTDIvol) and size-specific dose estimates did not differ significantly between acquisitions with the organ-specific dose reduction (1.7?±?0.8 mGy) and without the reduction (1.7?±?0.8 mGy) (P?>?0.05).Conclusion
Organ-specific dose reduction does not have an impact on image quality of pediatric chest CT and can therefore be used in clinical practice to reduce radiation dose of radiosensitive organs such as breast and thyroid gland. 相似文献44.
Sebastian T. Pohlack Patric Meyer Raffaele Cacciaglia Claudia Liebscher Stephanie Ridder Herta Flor 《Brain structure & function》2014,219(1):255-267
The importance of the hippocampus for declarative memory processes is firmly established. Nevertheless, the issue of a correlation between declarative memory performance and hippocampal volume in healthy subjects still remains controversial. The aim of the present study was to investigate this relationship in more detail. For this purpose, 50 healthy young male participants performed the California Verbal Learning Test. Hippocampal volume was assessed by manual segmentation of high-resolution 3D magnetic resonance images. We found a significant positive correlation between putatively hippocampus-dependent memory measures like short-delay retention, long-delay retention and discriminability and percent hippocampal volume. No significant correlation with measures related to executive processes was found. In addition, percent amygdala volume was not related to any of these measures. Our data advance previous findings reported in studies of brain-damaged individuals in a large and homogeneous young healthy sample and are important for theories on the neural basis of episodic memory. 相似文献
45.
Bergman E Kieler H Petzold M Sonesson C Axelsson O 《Acta obstetricia et gynecologica Scandinavica》2007,86(6):671-677
BACKGROUND: Antenatal identification of infants small for gestational age (SGA) improves their perinatal outcome. Repeated measurement of symphysis-fundus (SF) heights performed by midwives is the most widespread screening method for detection of SGA. However, the inefficiency of this method necessitates improved practices. Earlier start and more frequent SF measurements, which could be accomplished by self-administered measurements, might improve the ability to detect deviant growth. The present study was set up to evaluate whether pregnant women can reliably perform SF measurements by themselves. METHOD: Forty healthy women with singleton and ultrasound-dated pregnancies from 2 antenatal clinics in Uppsala, Sweden, were asked to perform 4 consecutive SF measurements once every week, from 20 to 25 weeks of gestation until delivery. The self-administered SF measurements were recorded and systematically compared with midwives' SF measurements. RESULTS: Thirty-three pregnant women performed self-administered SF measurements over a 14-week period (range: 1-21). The SF curves constructed from self-administered SF measurements had the same shape as previously constructed population-based reference curves. The variance for self-administered SF measurements was higher than that of the midwives. CONCLUSIONS: Pregnant women are capable of measuring SF heights by themselves, but with higher individual variance than midwives. Repeated measurements at each occasion can compensate for the higher variance. The main advantage of self-administered SF measurements is the opportunity to follow fetal growth earlier and more frequently. 相似文献
46.
47.
Yasser Alemn‐Gmez Elena Najdenovska Timo Roine Mrio Joo Fartaria Erick J. Canales‐Rodríguez Zita Rov Patric Hagmann Philippe Conus Kim Q. Do Paul Klauser Pascal Steullet Philipp S. Baumann Meritxell Bach Cuadra 《Human brain mapping》2020,41(14):4041-4061
The structural complexity of the thalamus, due to its mixed composition of gray and white matter, make it challenging to disjoint and quantify each tissue contribution to the thalamic anatomy. This work promotes the use of partial‐volume‐based over probabilistic‐based tissue segmentation approaches to better capture thalamic gray matter differences between patients at different stages of psychosis (early and chronic) and healthy controls. The study was performed on a cohort of 23 patients with schizophrenia, 41 with early psychosis and 69 age and sex‐matched healthy subjects. Six tissue segmentation approaches were employed to obtain the gray matter concentration/probability images. The statistical tests were applied at three different anatomical scales: whole thalamus, thalamic subregions and voxel‐wise. The results suggest that the partial volume model estimation of gray matter is more sensitive to detect atrophies within the thalamus of patients with psychosis. However all the methods detected gray matter deficit in the pulvinar, particularly in early stages of psychosis. This study demonstrates also that the gray matter decrease varies nonlinearly with age and between nuclei. While a gray matter loss was found in the pulvinar of patients in both stages of psychosis, reduced gray matter in the mediodorsal was only observed in early psychosis subjects. Finally, our analyses point to alterations in a sub‐region comprising the lateral posterior and ventral posterior nuclei. The obtained results reinforce the hypothesis that thalamic gray matter assessment is more reliable when the tissues segmentation method takes into account the partial volume effect. 相似文献
48.
Which heart failure patients profit from natriuretic peptide guided therapy? A meta‐analysis from individual patient data of randomized trials 下载免费PDF全文
Hans‐Peter Brunner‐La Rocca Luc Eurlings A. Mark Richards James L. Januzzi Matthias E. Pfisterer Ulf Dahlström Yigal M. Pinto Patric Karlström Hans Erntell Rudolf Berger Hans Persson Christopher M. O'Connor Deddo Moertl Hanna K. Gaggin Christopher M. Frampton M. Gary Nicholls Richard W. Troughton 《European journal of heart failure》2015,17(12):1252-1261
49.
Zhu M Li Y Xia Q Wang S Qiu Y Che M Dai H Qian J Ni Z Axelsson J Yan Y 《Transplantation proceedings》2010,42(9):3634-3638
Acute kidney injury (AKI) is a major complication in orthotopic liver transplantation (OLT). In an evaluation of Acute Kidney Injury Network (AKIN) criteria in liver transplanted patients, we retrospectively analyzed the usefulness of these criteria to predict survival of 193 consecutive patients at a single center who underwent primary OLT for clinical parameters and peak AKI. Postoperative AKI according to AKIN occurred in 60.1% of the patients, namely, stages 1, 2, and 3 in 30%, 13% and 17.1% respectively. Using multivariate logistic regression, AKIN stage 1 and 2 AKI were independently associated with the pre-OLT Model for End-Stage Liver Disease (MELD) score and age, while stage 3 AKI was independently associated with MELD and Acute Physiology and Chronic Health Evaluation (APACHE) II scores. The 28-day and 1-year mortality post-OLT of AKI patients were 15.5% and 25.9% respectively compared with 0% and 3.9% among non-AKI patients (P < .05 for both). The survival rates of non-AKI and stages 1, 2, and 3 AKI subjects were 96%, 85.5%, 84%, and 45.3%, respectively. Cox regression analysis showed independent risk factors for mortality during the first year after transplantation to include post-OLT AKI (12.1; P < .05), post-OLT infection (HR 4.7; P < .01), pre-OLT hypertension (HR 4.4; P < .01) hazard ratio [HR] and post-OLT APACHE II ≥10 (HR 3.6; P < .05). We concluded that AKI as defined by the AKIN criteria is a major complication of OLT linked to a poor outcomes. It remains to be evaluated whether aggressive perioperative therapy to prevent AKI can improve survival among OLT patients. 相似文献
50.
Orientation CP is the faster or more accurate discrimination of two orientations from different categories (e.g., oblique1 and vertical1) compared to two orientations from the same category (e.g., oblique1 and oblique2), even when the degree of difference is equated across conditions. Here, we assess whether there are hemispheric asymmetries in this effect for adults and 5-month-old infants. Experiment 1 identified the location of the vertical-oblique category boundary. Experiment 2, using a visual search task with oriented lines found that adult search was more accurate when the target and distractors were from different orientation categories, compared to targets and distractors of an equivalent physical difference taken from the same category. This effect was stronger for targets lateralized to the left visual field (LVF) than the right visual field (RVF), indicating a right hemisphere (RH) bias in adult orientation CP. Experiment 3, replicated the RH bias using different stimuli and also investigated the impact of visual and verbal interference on the category effect. Experiment 4, using the same visual search task, found that infant search was also faster when the target and distractors were from different orientation categories than the same, yet this category effect was stronger for RVF than LVF lateralized targets, indicating a LH bias in orientation CP at 5 months. These findings are contrasted to equivalent studies on the lateralization of color CP (e.g., Gilbert, Regier, Kay, & Ivry, 2005). The implications for theories on the contribution of the left and right hemispheres of the infant and adult brain to categorical computations are discussed. 相似文献