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61.
To study the direction and biomechanical consequences of hip center of rotation (HCOR) migration in Crowe type III and VI hips after total hip arthroplasty, post-operative radiographs and CT scans of several unilaterally affected hips were evaluated. Using a three-dimensional model of the human hip, the HCOR was moved in all directions, and joint reaction force (JRF) and abductor muscle force (AMF) were calculated for single-leg stance configuration. Comparing to the normal side, HCOR had displaced medially and inferiorly by an average of 23.4% and 20.8%, respectively, of the normal femoral head diameter. Significant decreases in JRF (13%) and AMF (46.13%) were observed in a presumptive case with that amount of displacement. Isolated inferior displacement had a small, increasing effect on these forces. In Crowe type III and IV hips, the HCOR migrates inferiorly and medially after THA, resulting in a decrease in JRF, AMF, and abductor muscle contraction force.  相似文献   
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The radial nerve constitutes a major problem in humeral shaft fractures; it may be injured immediately or during closed reduction or open reduction and internal fixation with plate and screws. After fixation, the nerve always runs directly over the plate without any interposed structure. If a revision surgery is indicated, the nerve is at high risk as it is usually difficult to dissect from surrounding fibrotic scar tissue or callus formation. To avoid these complications, some authors reported transposition of the radial nerve through the fracture line. We present herein the surgical technique of the trans-fracture transposition of the radial nerve during open reduction and internal fixation of humeral shaft fractures, along with our preliminary results in 6 cases and a review of the literature.  相似文献   
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BackgroundPalonosetron is a new, potent, and long-acting 5HT3-receptors antagonist that had been approved by the FDA for use in postoperative nausea and vomiting (PONV) prophylaxis. This study is designed to evaluate its efficacy combined with dexamethasone in PONV prophylaxis in highrisk patients scheduled for laparoscopic surgeries.MethodsIn this double-blind, active-controlled study, 150 patients aged 20–55 years, ASA I–II, and with Apfel’s PONV score 2–4 were equally randomized to receive dexamethasone 8 mg before anesthesia induction and saline 30 min before the end of surgery (group D + S), dexamethasone 8 mg before anesthesia induction and metoclopramide 25 mg 30 min before the end of surgery (group D + M), or dexamethasone 8 mg combined with palonosetron 0.075 mg before anesthesia induction and saline 30 min before the end of surgery (group D + P). Incidences of early and late PONV, complete response, adverse events from antiemetics used, and overall patients’ satisfaction were recorded.ResultsThe incidence of PONV was comparable in the three groups 0–6 h postoperatively. Palonosetron–dexamethasone and dexamethasone–metoclopramide combination therapies significantly reduced the incidence of PONV at 6–12 h postoperatively compared to dexamethasone monotherapy (12% and 16%, vs. 36%, respectively, with P < 0.05). Moreover, palonosetron–dexamethasone combination therapy significantly reduced the incidence of PONV at 12–24 h postoperatively compared to both dexamethasone monotherapy (16% vs. 48%, P < 0.01), and dexamethasone–metoclopramide combination therapy (16% vs. 40%, P < 0.05). The incidence of adverse drug effects was comparable in the three groups. The overall patients’ satisfaction was significantly higher in palonosetron–dexamethasone combination therapy compared to other groups.ConclusionPalonosetron–dexamethasone combination is effective and safe in PONV (early and late) prophylaxis in high-risk patients undergoing laparoscopic surgeries with known high-risk of PONV.  相似文献   
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Background: Periodontitis may occur in patients with and without type 2 diabetes (T2D). It may be hypothesized that the gingival crevicular fluid (GCF) cytokine profile in patients with periodontitis with poorly controlled T2D may differ from the GCF cytokine profile in medically healthy individuals with periodontitis. The aim was to review the cytokine profiles in the GCF of patients with periodontitis with and without T2D. Methods: Databases were searched from 1988 to August 2011 using different combinations of various keywords. Titles and abstracts of articles that satisfied the eligibility criteria were screened by the authors and checked for agreement. Only articles published in English were included. Results: Ten studies were included. Two studies reported GCF concentrations of interleukin (IL)‐6 to be higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. Two studies showed GCF IL‐6 levels to be higher in periodontitis with T2D compared to medically healthy subjects without periodontitis. In one study GCF levels of IL‐17, IL‐23, and interferon‐γ were higher in patients with periodontitis with T2D compared to medically healthy patients with periodontitis. In one study, GCF concentrations of IL‐8 were significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Three studies reported GCF levels of IL‐1α to be significantly higher in patients with periodontitis with T2D compared to medically healthy individuals with periodontitis. Conclusion: The GCF cytokine profile in patients with and without T2D seems to be governed by the intensity of periodontal inflammation and the role of T2D in this regard is rather secondary.  相似文献   
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Neurological Sciences - COVID-19 is a pandemic disease which predominantly affects the respiratory system with high critical care mortality and morbidity; however, it also causes multi-organ...  相似文献   
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Silver nanoparticles (SNPs) are widely used in nanomedicine and consuming products with potential risk to human health. While considerable work was carried out on the molecular, biochemical, and physiological alterations induced by these particles, little is known of the ultrastructural pathological alterations that might be induced by nanosilver materials. The aim of the present work is to investigate the hepatocyte ultrastructural alterations that might be induced by SNP exposure. Male rats were subjected to a daily single dose (2 mg/kg) of SNPs (15–35 nm diameter) for 21 days. Liver biopsies from all rats under study were processed for transmission electron microscopy examination. The following hepatic ultrastructural alterations were demonstrated: mitochondria swelling and crystolysis, endoplasmic reticulum disruption, cytoplasmic vacuolization, lipid droplets accumulation, glycogen depletion, karyopyknosis, apoptosis, sinusoidal dilatation, Kupffer cells activation, and myelin figures formation. The current findings may indicate that SNPs can induce hepatocyte organelles alteration, leading to cellular damage that may affect the function of the liver. These findings might indicate that SNPs potentially trigger heptocyte ultrastructural alterations that may affect the function of the liver with potential risk on human health in relation to numerous applications of these particles. More work is needed to elucidate probable ultrastructural alterations in the vital organs that might result from nanosilver toxicity.  相似文献   
70.
In this study we investigated the hypothesis whether P2-related differences tested in a visual priming paradigm are associated with theta phase-locking. We recorded the EEG from 31 electrodes and calculated phase-locking index and total power differences for frequencies between 2 and 20 Hz. ERPs (event-related potentials) were analyzed for P1, N1 and P2 components. P2 showed strongest task-related amplitude differences between congruent and incongruent targets. A source analyses was performed for the P2 component using sLoreta that revealed local generators of the P2 in parieto-occipital regions. Phase-locking analyses showed specific effects in the theta range (4-6 Hz) appearing in time windows at around the P2 component. We draw the conclusion that phase-locked theta reflect top-down regulation processes mediating information between memory systems and is in part involved in the modulation of the P2 component.  相似文献   
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