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81.

Introduction

The optimal treatment of high energy tibial fractures remains controversial and a challenging orthopaedic problem. The role of external fixators for all these tibial fractures has been shown to be crucial.

Methods

A five-year consecutive series was reviewed retrospectively, identifying two treatment groups: Ilizarov and Taylor Spatial Frame (TSF; Smith & Nephew, Memphis, TN, US). Fracture healing time was the primary outcome measure.

Results

A total of 112 patients (85 Ilizarov, 37 TSF) were identified for the review with a mean age of 45 years. This was higher in women (57 years) than in men (41 years). There was no significant difference between frame types (p=0.83). The median healing time was 163 days in both groups. There was no significant difference in healing time between smokers and non-smokers (180 vs 165 days respectively, p=0.07), open or closed fractures (p=0.13) or age and healing time (Spearman''s r=0.12, p=0.18). There was no incidence of non-union or re-fracture following frame removal in either group.

Conclusions

Despite the assumption of the rigid construct of the TSF, the median time to union was similar to that of the Ilizarov frame and the TSF therefore can play a significant role in complex tibial fractures.  相似文献   
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Highly purified, Escherichia coli-derived recombinant human tumor necrosis factor (TNF) was labeled with 125I and employed to determine receptor binding, internalization, and intracellular degradation in murine L929 cells (highly sensitive to the cytotoxic action of TNF) and in diploid human FS-4 cells (resistant to TNF cytotoxicity). 125I-labeled TNF bound specifically to high-affinity receptors on both L929 and FS-4 cells. Scatchard analysis of the binding data indicated the presence of 2200 binding sites per L929 cell and 7500 binding sites per FS-4 cell. The calculated dissociation constants are 6.1 X 10(-10) M and 3.2 X 10(-10) M for L929 and FS-4 cells, respectively. In both L929 and FS-4 cells, incubation at 37 degrees C resulted in a rapid internalization of the bulk of the cell-bound TNF, followed by the appearance of trichloroacetic acid-soluble 125I radioactivity in the tissue culture medium, due to degradation of TNF. Degradation but not cellular uptake of TNF was inhibited in the presence of chloroquine (an inhibitor of lysosomal proteases) in both L929 and FS-4 cells, suggesting that degradation occurs intracellularly, probably within lysosomes. These results show that resistance of FS-4 cells to TNF cytotoxicity is not due to a lack of receptors or their inability to internalize and degrade TNF.  相似文献   
85.
A complete experimental format is given for the reconstitution of human hemoglobin from the separated heme-free alpha- and beta-globin chains (alpha degrees, beta degrees) and hemin, by two alternative routes. Based on their oxygen binding properties, the reaction of the ferri-forms with reducing agent, and the response of the oxygen binding curves to pH variation and to the addition of the allosteric effector 2,3-diphosphoglycerate, the molecules are native. One reconstitution route uses direct addition of hemin to the separated globin chains with production of the separated subunits, which can then be recombined and reduced. This procedure occasions losses by precipitation in the heme-addition step except at high dilutions, and the yields are low. In the second pathway, either globin chain is mixed with the complementary untreated subunit to form the half-filled (with heme) intermediates, which combine stoichiometrically with hemin. No precipitation accompanies these reactions. For alpha-globin, the yield is about 50% because of incomplete combination with the heme-containing beta chain. For beta-globin, the yield is better than 70%. It is suggested that experiments intended to test either globin chain should use the second route in preparation for structural or functional comparisons with native hemoglobin.  相似文献   
86.
Multimorbidity, defined as the presence of two or more chronic conditions, leads to a substantial public health burden. This study evaluated its association with adherence with cardiovascular medications in a Chinese population.  相似文献   
87.
Because of their high efficiency and sharp emission, perovskite light-emitting diodes are a promising candidate for next-generation lighting techniques. However, the relatively poor stability of perovskite light-emitting diodes lowers their utility. Therefore, a highly stable perovskite light-emitting diode has to be developed to meet the commercial demand. Herein, we report a highly stable CsPbBr3 light-emitting diode via simple polymer treatment. The addition of 2-methyl-2-oxazoline in perovskite film assists the formation of CsPbBr3 nanocrystals, improving the quality and photoluminescence property of perovskite film. Based on such CsPbBr3 nanocrystals and polymer hybrid film, our device presents a high external quantum efficiency and luminance of around 3.0% and 16 648 cd m−2, respectively. Moreover, an excellent device half-lifetime of more than 2.4 hours has been achieved, under continuous operation at a relatively high initial luminance of 1000 cd m−2, representing one of the most stable PeLEDs operated at such high initial luminance.

The 2-methyl-2-oxazoline additive induced the formation of high-quality CsPbBr3 nanocrystals and a stable PeLED with a half-lifetime of 2.4 hours at high initial luminance of 1000 cd m−2 was demonstrated, representing one of the most stable PeLEDs.  相似文献   
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Molecular Imaging and Biology - This study aimed to investigate the feasibility of diffusion tensor imaging (DTI) and T2-mapping to assess temporal renal damage in deoxycorticosterone...  相似文献   
90.
Neonatal resuscitation is a coordinated, team-based series of timed sequential steps that focuses on a transitional physiology to improve perinatal and neonatal outcomes. The practice of neonatal resuscitation has evolved over time and continues to be shaped by emerging evidence as well as key opinions. We present the revised Neonatal Resuscitation Guidelines for Singapore 2021. The recommendations from the International Liaison Committee on Resuscitation Neonatal Task Force Consensus on Science and Treatment Recommendations (2020) and guidelines from the American Heart Association and European Resuscitation Council were compared with existing guidelines. The recommendations of the Neonatal Subgroup of the Singapore Resuscitation and First Aid Council were derived after the work group discussed and appraised the current available evidence and their applicability to local clinical practice.  相似文献   
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