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61.
Felix Bachelier Antonius Pizanis Julia Schwitalla Tim Pohlemann Dieter Kohn Reiner Wirbel 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2014,24(5):707-714
Background and purpose
The functional results and the complications following interlocking plate fixation of displaced proximal humerus fractures should be evaluated and compared with those following minimal invasive fixation techniques.Patients and methods
Fifty patients (30 women, 20 men, mean age 62.7 (18–91) years) were treated for a displaced proximal humerus fracture using an interlocking plate fixation (PHILOS®) between 2003 and 2004. The mean follow-up time was 12 (9–36) months. Functional and radiographic results (Constant-Murley and Neer scores) were analyzed and compared with an equivalent historical control group of 53 patients operated for the same fracture types using minimal invasive techniques (K-wires and/or cannulated screws) between 1995 and 1997. According to the OTA/AO classification, there were 15 type A, 18 type B, and 17 type C fractures in the plate fixation group, and 23, 25, and 5 of these types in the control group, respectively.Results
The mean Neer score was 85.9, the mean Constant-Murley score 84, whereas 82.4 and 75.4 for the control group, respectively. Good and excellent results were seen in 78 %, whereas in 70 % in the control group. The results were dependent upon the fracture’s type, sex, and patient’s age. Complications were seen in 9 patients, whereas in 16 patients in the control group.Interpretation
Using an interlocking plate, the indication of fixation of displaced proximal humerus fractures had been expanded to type C fractures. The implant failure rate can be reduced. The functional results achieved are better compared with those following minimal invasive techniques. 相似文献62.
Transduction of pluripotent human hematopoietic stem cells demonstrated by clonal analysis after engraftment in immune-deficient mice. 总被引:8,自引:0,他引:8 下载免费PDF全文
J A Nolta M A Dao S Wells E M Smogorzewska D B Kohn 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(6):2414-2419
Gene transduction of pluripotent human hematopoietic stem cells (HSCs) is necessary for successful gene therapy of genetic disorders involving hematolymphoid cells. Evidence for transduction of pluripotent HSCs can be deduced from the demonstration of a retroviral vector integrated into the same cellular chromosomal DNA site in myeloid and lymphoid cells descended from a common HSC precursor. CD34+ progenitors from human bone marrow and mobilized peripheral blood were transduced by retroviral vectors and used for long-term engraftment in immune-deficient (beige/nude/XIS) mice. Human lymphoid and myeloid populations were recovered from the marrow of the mice after 7-11 months, and individual human granulocyte-macrophage and T-cell clones were isolated and expanded ex vivo. Inverse PCR from the retroviral long terminal repeat into the flanking genomic DNA was performed on each sorted cell population. The recovered cellular DNA segments that flanked proviral integrants were sequenced to confirm identity. Three mice were found (of 24 informative mice) to contain human lymphoid and myeloid populations with identical proviral integration sites, confirming that pluripotent human HSCs had been transduced. 相似文献
63.
Ahmed F. Shakarchi Lama Assi Abhishek Gami Christina Kohn Joshua R. Ehrlich Bonnielin K. Swenor Nicholas S. Reed 《Seminars in hearing》2021,42(1):75
With the aging of the population, vision (VL), hearing (HL), and dual-sensory (DSL, concurrent VL and HL) loss will likely constitute important public health challenges. Walking speed is an indicator of functional status and is associated with mortality. Using the Health and Retirement Study, a nationally representative U.S. cohort, we analyzed the longitudinal relationship between sensory loss and walking speed. In multivariable mixed effects linear models, baseline walking speed was slower by 0.05 m/s (95% confidence interval [CI] = 0.04–0.07) for VL, 0.02 (95% CI = 0.003–0.03) for HL, and 0.07 (95% CI = 0.05–0.08) for DSL compared with those without sensory loss. Similar annual declines in walking speeds occurred in all groups. In time-to-event analyses, the risk of incident slow walking speed (walking speed < 0.6 m/s) was 43% (95% CI = 25–65%), 29% (95% CI = 13–48%), and 35% (95% CI = 13–61%) higher among those with VL, HL, and DSL respectively, relative to those without sensory loss. The risk of incident very slow walking speed (walking speed < 0.4 m/s) was significantly higher among those with HL and DSL relative to those without sensory loss, and significantly higher among those with DSL relative to those with VL or HL alone. Addressing sensory loss and teaching compensatory strategies may help mitigate the effect of sensory loss on walking speed. 相似文献
64.
Muhammad Umair Khan Michael Kohn Parisa Aslani 《Research in social & administrative pharmacy》2019,15(3):318-320
Nonadherence to long-term medications attenuates optimum health outcomes. There is an abundance of research on measuring and identifying factors affecting medication adherence in a range of chronic medical conditions. However, there is a lack of standardisation in adherence research, namely in the methods and measures used. In the case of attention deficit hyperactivity disorder, this lack of standardisation makes it difficult to compare and combine findings and to draw meaningful conclusions. Standardisation should commence with a universally accepted categorisation or taxonomy of adherence which takes into consideration the dynamic nature of medication-taking. This should then be followed by the use of valid and reliable measures of adherence which can accurately quantify adherence at any of its phases, and provide useful information which can be utilised in planning targeted interventions to improve adherence throughout the patient medication-taking journey. 相似文献
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67.
Altered brain network integrity after childhood maltreatment: A structural connectomic DTI‐study 下载免费PDF全文
Childhood maltreatment is associated with alterations in neural architecture that potentially put these children at increased risk for psychopathology. Alterations in white matter (WM) tracts have been reported, however no study to date has investigated WM connectivity in brain networks in maltreated children to quantify global and local abnormalities through graph theoretical analyses of DTI data. We aimed for a multilevel investigation examining the DTI‐based structural connectome and its associations with basal cortisol levels of 25 children with documented maltreatment experiences before age 3, and 24 matched controls (age: 10.6 ± 1.75 years). On the global and lobar level, maltreated children showed significant reductions in global connectivity strength, local connectivity and increased path length, suggesting deviations from the small‐world network architecture previously associated with psychopathology. Reductions in global connectivity were associated with placement instability, attenuated cortisol secretion and higher levels of internalizing and externalizing behaviours. Regional measures revealed lower connectivity strength especially in regions within the ventromedial prefrontal cortex (vMPFC) in maltreated children. These findings show that childhood maltreatment is associated with systemic global neurodevelopmental alterations in WM networks next to regional alterations in areas involved in the regulation of affect. These alterations in WM organization could underlie global functional deficits and multi‐symptom patterns frequently observed in children with maltreatment experiences. Hum Brain Mapp 38:855–868, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
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69.
Cartilage damage is often associated with pain, reduced quality of life and decreased physical performance. In addition, even small cartilage lesions can lead to osteoarthritis. Since young active people are particularly affected, the correct treatment of cartilage damage plays an important role. Operative treatment includes bone marrow-stimulating procedures with or without a matrix, cell-based procedures and osteochondral graft transplantation. The choice of the best procedure depends on the localization, the size and the extent of the cartilage damage. In addition, especially in the treatment of cartilage damage to the lower limbs, the leg axis and loading relationships should be taken into account and possibly treated as well as additional joint instabilities. The following article gives an overview of the available surgical treatment possibilities as well as the correct indications and implementation. It also gives a brief projection of possible further treatment options associated with stem cells. 相似文献
70.
We have identified a polymeric system based on a novel tyrosine-derived terpolymer that offers desirable insertion capability for flexible neural prosthetic devices. To test this concept, flexible films were coated with this terpolymer and their suitability for peranchyma insertion was visualized. The effect of the polymer on neural recording was evaluated using coated microwire probes. The stiff but readily resorbable polymer rapidly degrades (molecular weight half-life of 170 min) while turning into a soft gel, followed by complete resorption within 240 min. This polymeric platform maintains sufficient stiffness to facilitate pial penetration with a dry elastic modulus of 393±44 MPa but loses its strength within 30 min once immersed in saline. In vitro, the polymer's ability to locally deliver dexamethasone has been confirmed through a first order release profile over a 360 min period. In vitro, coated microwire probes regained their original impedance values of 0.5 KΩ within 20 min of wetting via water absorption and polymer resorption. In vivo, the retention of electrical recording capability was also demonstrated through multiple waveform detection in live animals. The ultrafast resorbing polymer as a platform to facilitate the implantation of micronized flexible probes can be utilized in future designs of chronic neural devices. 相似文献