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51.
目的 探讨计算机软件应用于C1侧块骨折三维重建、复位以及数字化模拟Magerl技术内固定的方法及临床意义,以指导临床应用.方法 将1具颈椎标本制作成C1侧块骨折类型,进行高速CT薄层扫描,在Mimics中对C1侧块骨折模型进行重建、复位,以Solidworks进行螺钉的设计,并在骨折复位三维模型上进行虚拟Magerl技术内固定.结果 对骨折进行了三维重建、复位,根据三维模型测量数据,完成虚拟螺钉内固定,并成功指导临床手术21例.结论 应用Mimics及Solidworks可在个人电脑上设计出C1侧块骨折数字化螺钉固定,对临床手术有很好的参考意义. 相似文献
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Rohini Sharma Lars Wilkinson Hrvoje Vrazic Evan Popoff Sandra Lopes Steve Kanters 《Current medical research and opinion》2018,34(9):1595-1603
Objective: Treatment intensification with additional anti-diabetic agents is recommended in type 2 diabetes (T2D) for patients inadequately controlled on metformin monotherapy. The present network meta-analysis (NMA) evaluated comparative efficacy and safety of once-weekly semaglutide and sodium-glucose co-transporter 2 inhibitors (SGLT-2is) in T2D patients inadequately controlled with metformin.Methods: Randomized controlled trials with ≥20 weeks duration were searched in EMBASE, MEDLINE, and CENTRAL. Primary efficacy outcomes were: change from baseline in HbA1c, weight, systolic blood pressure (SBP), post-prandial blood glucose (PPG), and fasting blood glucose (FPG). Treatment effects at 26 (±4) weeks were compared using Bayesian NMAs. Meta-regression and sensitivity analysis were used to address the trial heterogeneity.Results: Eight trials were found eligible for this NMA. Statistically significant reductions in HbA1c were observed with both 1.0?mg and 0.5?mg doses of once-weekly semaglutide when compared to SGLT-2is. The mean differences in change from baseline in HbA1c for once-weekly semaglutide 1.0?mg vs SGLT-2is ranged from ?0.66% for canagliflozin 300?mg (95% Credible Intervals [CrI]: ?0.82, ?0.50%) to ?1.11% for dapagliflozin 5?mg (95% CrI: ?1.37, ?0.85%). Once-weekly semaglutide 1.0?mg performed significantly better than all SGLT-2is of interest in reducing weight and improving FPG levels: however, SBP reduction was not statistically differentiable. Results of sensitivity analysis and meta-regressions aligned with base-case results. NMAs were not possible for PPG and safety outcomes, due to lack of data.Conclusion: Once-weekly semaglutide treatment is significantly better compared to SGLT-2is in achieving adequate glycemic control in T2D patients inadequately controlled with metformin monotherapy. 相似文献
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Ebrahim Amini Hamid Reza Marzban Mahdi Rastegari 《Optimal control applications & methods.》2020,41(5):1735-1748
By going to millimeter wave (mmWave) we can use large scale MIMO due to short mmWave wavelength to overcome path loss by using beamforming to focus power of signal to the receiver. System structure of mmWave band is different with conventional MIMO because of large scale MIMO which is leading to use many RF-chains. For this reason Hybrid structure have been proposed for large Scale MIMO. By going to Hybrid structure a new issue has been created with phase shifter constraint. In this paper we propose a novel solution to make a hybrid precoding and combing to reach high spectral efficiency. Our problem includes a maximizing Frobenius norm of multiplying five complex matrices. As constraints, all elements of some matrices must have unit norm, and also the multiplication of some matrices must have a specific Frobenius norm. A novel solution is proposed for the problem, which is gained in two steps. At the first step, we propose a new decomposition usable for kind of complex matrices which could lead to reduce the dimension of the objective function, and eliminating constraints completely and in the second step, we propose an iterated algorithm for the resulting problem. By proposing another novel technique, we show that in each iteration, the optimal problem is equivalent to a quadratic optimal problem with limitations on the vector norm, and as a result, an optimal problem is obtained quickly. Moreover, some other real examples are included to demonstrate the usefulness and effectiveness of the proposed algorithm. 相似文献
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Stefanos Kachrilas Elenko Popov Andreas Bourdoumis Waseem Akhter Mohamed El Howairis Ismaeel Aghaways Junaid Masood Noor Buchholz 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2014,18(3)
Background and Objectives:
To evaluate the usefulness of laparoscopic varicocelectomy in the management of chronic scrotal pain.Methods:
Between 2009 and 2011, 48 patients in total were treated with laparoscopic varicocelectomy for dull scrotal pain that worsened with physical activity and was attributed to varicoceles. All patients were followed up at 3 and 6 months and biannually thereafter with a physical examination, visual analog scale score, and ultrasonographic scan in selected cases.Results:
The mean age was 38.2 years (range, 23–54 years). The mean follow-up period was 19.6 months (range, 6–26 months). Bilateral varicoceles were present in 7 patients (14.6%), and a unilateral varicocele was present in 41 (85.4%). The varicocele was grade 3 in 27 patients (56.3%), grade 2 in 20 (41.6%), and grade 1 in 1 (2.1%). The mean preoperative visual analog scale score was 4.8 on a scale from 0 to 10. The mean postoperative visual analog scale score at 3 months was 0.8. After the procedure, 42 patients (87.5%) had a significant improvement in the visual analog scale score (P < .001); 5 (10.4%) had symptom improvement, although it was not statistically significant; and 1 (2.1%) remained unchanged. During follow-up, we observed 5 recurrences (10.4%) whereas de novo hydrocele formation was identified in 4 individuals (8.3%).Conclusion:
Laparoscopic varicocelectomy is efficient in the treatment of symptomatic varicoceles with a low complication rate. However, careful patient selection is necessary because it appears that individuals presenting with sharp, radiating testicular pain and/or a low-grade varicocele are less likely to benefit from this procedure. 相似文献58.
Tetrandrine, a constituent of Chinese herb Stephania tetrandra, causes cell death in prostate cancer, but the molecular mechanisms leading to apoptosis is not known. Here we demonstrated that tetrandrine selectively inhibits the growth of prostate cancer PC3 and DU145 cells compared to normal prostate epithelial PWR-1E cells. Tetrandrine-induced cell death in prostate cancer cells is caused by reactive oxygen species (ROS)-mediated activation of c-Jun NH2-terminal kinase (JNK1/2). JNK1/2-mediated proteasomal degradation of c-FLIPL/S and Bcl2 proteins are key events in the sensitization of prostate cancer cells to Fas- and mitochondria-mediated apoptosis by tetrandrine. Tetrandrine-induced JNK1/2 activation caused the translocation of Bax to mitochondria by disrupting its association with Bcl2 which was accompanied by collapse of mitochondrial membrane potential (MMP), cytosolic release of cytochrome c and Smac, and apoptotic cell death. Additionally, tetrandrine-induced JNK1/2 activation increased the phosphorylation of Bcl2 at Ser70 and facilitated its degradation via the ubiquitin-mediated proteasomal pathway. In parallel, tetrandrine-mediated ROS generation also caused the induction of ligand-independent Fas-mediated apoptosis by activating procaspase-8 and Bid cleavage. Inhibition of procaspase-8 activation attenuated the cleavage of Bid, loss of MMP and caspase-3 activation suggest that tetrandrine-induced Fas-mediated apoptosis is associated with the mitochondrial pathway. Furthermore, most of the signaling effects of tetrandrine on apoptosis were significantly attenuated in the presence of antioxidant N-acetyl-l-cysteine, thereby confirming the involvement of ROS in these events. In conclusion, the results of the present study indicate that tetrandrine-induced apoptosis in prostate cancer cells is initiated by ROS generation and that both intrinsic and extrinsic pathway contributes to cell death. 相似文献
59.
Identification of Nucleoside Analogs as Inducers of Neuronal Differentiation in a Human Reporter Cell Line and Adult Stem Cells 下载免费PDF全文
Katharina Raasch Edith Malecki Maria Siemann Malayko M. Martinez Jürgen J. Heinisch Janine Müller Lidia Bakota Christian Kaltschmidt Barbara Kaltschmidt Helmut Rosemeyer Roland Brandt 《Chemical biology & drug design》2015,86(2):129-143
Nucleoside analogs (NSAs) were among the first chemotherapeutic agents and could also be useful for the manipulation of cell fate. To investigate the potential of NSAs for the induction of neuronal differentiation, we developed a novel phenotypic assay based on a human neuron‐committed teratocarcinoma cell line (NT2) as a model for neuronal progenitors and constructed a NT2‐based reporter cell line that expressed eGFP under the control of a neuron‐specific promoter. We tested 38 structurally related NSAs and determined their activity to induce neuronal differentiation by immunocytochemistry of neuronal marker proteins, live cell imaging, fluorometric detection and immunoblot analysis. We identified twelve NSAs, which induced neuronal differentiation to different extents. NSAs with highest activity carried a halogen substituent at their pyrimidine nucleobase and an unmodified or 2′‐O‐methyl substituted 2‐deoxy‐β‐D‐ribofuranosyl residue as glyconic moiety. Cladribine, a purine nucleoside with similar structural features and in use to treat leukemia and multiple sclerosis, induced also differentiation of adult human neural crest‐derived stem cells. Our results suggest that NSAs could be useful for the manipulation of neuronal cell fate in cell replacement therapy or treatment of neurodegenerative disorders. The data on the structure and function relationship will help to design compounds with increased activity and low toxicity. 相似文献
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Robbert M. Wouters Jonathan Tsehaie Harm P. Slijper Steven E.R. Hovius Reinier Feitz 《Archives of physical medicine and rehabilitation》2019,100(6):1050-1060
ObjectiveTo compare the effect of exercises and orthotics with orthotics alone on pain and hand function in patients with first carpometacarpal joint (CMC-1) osteoarthritis (OA) and to predict outcomes on pain and hand function of exercises and orthotics.DesignProspective cohort study with propensity score matching.SettingData collection took place in 13 outpatient clinics for hand surgery and hand therapy in The Netherlands.ParticipantsA consecutive, population-based sample of patients with CMC-1 OA (N=173) was included in this study, of which 84 were matched on baseline demographics and baseline primary outcomes.InterventionsExercises and orthotics versus orthotics alone.Main Outcome MeasuresPrimary outcomes included pain and hand function at 3 months, measured using visual analog scale (VAS, 0-100) and the Michigan Hand Outcomes Questionnaire (MHQ, 0-100).ResultsA larger decrease in VAS pain at rest (11.1 points difference; 95% confidence interval, 1.9-20.3; P=.002) and during physical load (22.7 points difference; 95% confidence interval, 13.6-31.0; P<.001) was found in the exercise + orthotic group compared to the orthotic group. In addition, larger improvement was found for the MHQ subscales pain, work performance, aesthetics, and satisfaction in the exercise + orthotic group. No differences were found on other outcomes. Baseline scores of metacarpophalangeal flexion, presence of scaphotrapeziotrapezoid OA, VAS pain at rest, heavy physical labor, and MHQ total predicted primary outcomes for the total exercise + orthotic group (N=131).ConclusionsNon-surgical treatment of patients with CMC-1 OA should include exercises, since there is a relatively large treatment effect compared to using an orthosis alone. Future research should study exercises and predictors in a more standardized setting to confirm this finding. 相似文献