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121.
目的:利用葡萄糖定量法检测根管微渗漏模型,评价侧向加压充填技术、垂直加压充填技术及固核载体充填技术对根管微渗漏的影响.方法:选取71颗直根管上前牙,根管预备后随机分为7组,A组(14颗)用热牙胶垂直加压加AH Plus充填;B组(8颗)仅用热牙胶垂直加压充填;C组(13颗)用侧方加压加AH Plus充填;D组(8颗)仅用侧方加压充填技术;E组(11颗)用Thermafil加AH Plus充填;F组(7颗)仅用Thermafil充填;G组(10颗)为阴性对照组,用粘蜡充填根管.牙根外表面、根管口及根尖孔处涂二层指甲油.于第7 d、14 d、21 d、28 d用葡萄糖氧化酶法检测从冠方向根方漏出的葡萄糖量.结果:采用重复测量方差分析,发现第7 d、14 d、21 d、28 d A、C组及C、E组微渗漏值有显著性差异(P<0.001),但A、E组无显著性差异(P>0.05).各时间点C、D组比较有显著性差异(P<0.001),但A、B组与E、F组比较无显著性差异(P>0.05).第7 d、14 d及第21 d、28 d各组内比较无显著性差异(P>0.05),但各组第14 d与第21 d比较有显著性差异(P<0.05).结论:侧方加压充填技术封闭根管的能力优于垂直加压充填技术及固核载体充填技术,而后两种充填技术封闭根管的能力相当. 相似文献
122.
Zuhier A. Awan Shareefa A. AlGhamdi Nabil A. Alhakamy Solomon Z. Okbazghi Mohamed A. Alfaleh Shaimaa M. Badr-Eldin Hibah M. Aldawsari Mohammed A. S. Abourehab Hani Z. Asfour Shadi A. Zakai Mohammad W. Alrabia Aya A. Negm Mohamed A. El-Moselhy Sara S. Sharkawi Waleed Y. Rizg 《Drug delivery》2022,29(1):1536
Certain anticancer agents selectively target the nucleus of cancer cells. One such drug is 2-methoxyestradiol (2ME), which is used for treating lung cancer. To improve the therapeutic effectiveness of these agents, many new methods have been devised. 2ME was entrapped into the core of hydrophobic invasomes (INVA) covered with Phospholipon 90G and apamin (APA). The Box–Behnken statistical design was implemented to enhance the composition. Using Design-Expert software (Stat-Ease Inc., Minneapolis, MN), the INVA component quantities were optimized to obtain spherical particles with the smallest size, that is, a diameter of 167.8 nm. 2ME-INVA-APA significantly inhibited A549 cells and exhibited IC50 of 1.15 ± 0.04 µg/mL, which is lower than raw 2ME (IC50 5.6 ± 0.2 µg/mL). Post 2ME-INVA-APA administration, a significant rise in cell death and necrosis was seen among the A549 cells compared to those treated with plain formula or 2ME alone. This effect was indicated by increased Bax expression and reduced Bcl-2 expression, as well as mitochondrial membrane potential loss. Moreover, the cell cycle analysis showed that 2ME-INVA-APA arrests the G2-M phase of the A549 cells. Additionally, it was observed that the micellar formulation of the drug increased the cell count in pre-G1, thereby exhibiting phenomenal apoptotic potential. Furthermore, it up-regulates caspase-9 and p53 and downregulates TNF-α and NF-κβ. Collectively, these findings showed that our optimized 2ME-INVA-APA could easily seep through the cell membrane and induce apoptosis in relatively low doses. 相似文献
123.
Zhang Xu Jung-Hyun Choi David L. Dai Jun Luo Reese Jalal Ladak Qian Li Yimeng Wang Christine Zhang Shane Wiebe Alex C. H. Liu Xiaozhuo Ran Jiaqi Yang Parisa Naeli Aitor Garzia Lele Zhou Niaz Mahmood Qiyun Deng Mohamed Elaish Rongtuan Lin Lara K. Mahal Tom C. Hobman Jerry Pelletier Tommy Alain Silvia M. Vidal Thomas Duchaine Mohammad T. Mazhab-Jafari Xiaojuan Mao Seyed Mehdi Jafarnejad Nahum Sonenberg 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
124.
目的:评估传统与欠矫手术治疗部分调节性内斜视患者的效果。
方法:将25例具有部分调节性内斜视和正常AC/A的患者随机分为两组,其中13例患者接受传统手术治疗,其余12例患者接受欠矫手术治疗。传统手术是基于远距远视完全矫正所测量的偏差上,而欠矫手术比传统手术标准低20%。所有患者均进行对称性双眼内直肌后退术,术后随访6mo。
结果:术后6mo,传统组与欠矫组手术成功率分别为46%和91%(成功标准定义为通过近距和远距远视的完全矫正斜视≤8^△)。传统组和欠矫组的手术过矫率分别为54%和9%,两组间差异有统计学意义(P〈0.05)。没有残余内斜视。手术成功率或欠矫率与患者的年龄、术前等效球镜均值、术前眼偏斜量无相关性。
结论:对于具有正常AC/A的部分调节性内斜视患者,欠矫的双眼内直肌后退术成功率较高,过矫率较低。 相似文献
125.
Ramy Sadek Mohammad S. Sharawi Charles Dubois Hesham Tantawy Jamal Chaouki 《RSC advances》2022,12(35):22608
The chemical reduction process of graphene oxide combined with a mild and controllable thermal treatment under vacuum at 200 °C for 4 hours provided a cost-effective, scalable, and high-yield route for Reduced Graphene Oxide (RGO) industrial production and became a potential candidate for producing electromagnetic interference (EMI) shielding. We investigated graphite, and RGO using l-ascorbic acid and Sodium borohydride before and after thermal treatment by carefully evaluating the chemical and morphological structures. The thermally treated l-ascorbic Acid reduction route (TCRGOL) conductivity was 2.14 × 103 S m−1 and total shielding efficiency (SET) based on mass loadings per area of shielding was 94 dB with about one-tenth less graphite weight and surpassing other graphene reduction mechanisms in the frequency range of 8.2–12.4 GHz, i.e., X-band, at room temperature while being tested using the waveguide line technique. The developed treatment represents valuable progress in the path to chemical reduction using a safe reducing agent and offering superior quality RGO rarely achieved with the top-down technique, providing a high EMI shielding performance.The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers), and its SET was 94 dB over the X-band. 相似文献
126.
Lever R Lo WT Faraidoun M Amin V Brown RA Gallagher J Page CP 《British journal of pharmacology》2007,151(6):837-843
BACKGROUND AND PURPOSE: Heparin is known to possess a range of activities, other than effects on blood coagulation, many of which are anti-inflammatory. Effects with potential anti-inflammatory applications include the inhibition of elastase release from neutrophils, as well as the adhesion of these cells to vascular endothelium. In the present study we aimed to investigate whether fractionation of heparin may yield molecules with enhanced or specific effects on human neutrophil function. EXPERIMENTAL APPROACH: Fractions of defined molecular size were obtained from heparin by different methods and assessed for their effects on elastase release induced by formyl Met-Leu-Phe (fMLP), from neutrophils, in some cases following the priming of these cells with tumour necrosis factor-alpha (TNF-alpha). Effects of the fractions on neutrophil adhesion to interleukin-1beta (IL-beta)-stimulated human umbilical vein endothelial cells (HUVECs) were also examined. KEY RESULTS: Elastase release was inhibited by very low molecular weight fractions of heparin, with an apparent minimum chain length of 10 saccharides required for full effect. In contrast, neutrophil-endothelial adhesion was unaffected by these fractionated heparins, suggesting that certain non-anticoagulant actions of heparin may be lost by such an approach. CONCLUSIONS AND IMPLICATIONS: These data suggest that an optimum chain length of heparin possibly exists for certain non-anticoagulant actions of heparin, which may prove to be useful in the design of novel drugs with specific anti-inflammatory actions. 相似文献
127.
128.
Alfredo Oliveros Ki Hyun Yoo Mohammad Abdur Rashid Ana Corujo-Ramirez Benjamin Hur Jaeyun Sung Yuanhang Liu John R. Hawse Doo-Sup Choi Detlev Boison Mi-Hyeon Jang 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(28)
Chemotherapy-induced cognitive impairment (CICI) has emerged as a significant medical problem without therapeutic options. Using the platinum-based chemotherapy cisplatin to model CICI, we revealed robust elevations in the adenosine A2A receptor (A2AR) and its downstream effectors, cAMP and CREB, by cisplatin in the adult mouse hippocampus, a critical brain structure for learning and memory. Notably, A2AR inhibition by the Food and Drug Administration–approved A2AR antagonist KW-6002 prevented cisplatin-induced impairments in neural progenitor proliferation and dendrite morphogenesis of adult-born neurons, while improving memory and anxiety-like behavior, without affecting tumor growth or cisplatin’s antitumor activity. Collectively, our study identifies A2AR signaling as a key pathway that can be therapeutically targeted to prevent cisplatin-induced cognitive impairments. 相似文献
129.
Zahra Davoudi Mohammad Hallajnejad Elena Jamali Mohammadjavad Honarvar 《Clinical Case Reports》2022,10(7)
Refractory aggressive prolactinomas are detected after the unresponsiveness to conventional therapies. We report two cases that underwent temozolomide treatment and have been in near‐complete remission ever since. We suggest the pathology techniques for earlier detection and, subsequently, treatment with temozolomide to reduce morbidities and better respond to therapy. 相似文献
130.
Natago Guil Mbodj Mohammad Abuabiah Peter Plapper Maxime El Kandaoui Slah Yaacoubi 《Materials》2022,15(13)
Laser Wire Additive Manufacturing (LWAM) is a flexible and fast manufacturing method used to produce variants of high metal geometric complexity. In this work, a physics-based model of the bead geometry including process parameters and material properties was developed for the LWAM process of large-scale products. The developed model aimed to include critical process parameters, material properties and thermal history to describe the relationship between the layer height with different process inputs (i.e., the power, the standoff distance, the temperature, the wire-feed rate, and the travel speed). Then, a Model Predictive Controller (MPC) was designed to keep the layer height trajectory constant taking into consideration the constraints faced in the LWAM technology. Experimental validation results were performed to check the accuracy of the proposed model and the results revealed that the developed model matches the experimental data. Finally, the designed MPC controller was able to track a predefined layer height reference signal by controlling the temperature input of the system. 相似文献