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991.
目的探讨复方甘草酸苷在防治原发性肝癌(PLC)三维适形放疗(3DCRT)后肝损伤的作用。方法 113例PLC患者被随机分为治疗组62例和对照组51例,两组均采用3DCRT治疗,分割剂量为2.6~3.2Gy/次,总剂量为48~60Gy;治疗组同时给予复方甘草酸苷注射液60~100 ml/日,静脉滴注,疗程4周,再改为片剂口服,共2~3个月。结果两组患者放疗后ALT和AST较放疗前均有所升高,但治疗组ALT(51.6±12.6 U/L)和AST(48.3±14.4 U/L)升高程度明显低于对照组(分别为85.2±19.9 U/L和73.8±17.8 U/L,P〈0.01);治疗组发生放射性肝病(RILD)4例(6.5%),而对照组发生10例(19.6%),治疗组明显低于对照组(P〈0.05)。结论复方甘草酸苷能预防和改善PLC患者在3DCRT治疗后的肝损伤,降低RILD的发生率。 相似文献
992.
To reveal the friction mechanism of molybdenum disulfide (MoS2), the frictional properties of multilayer MoS2 lubrication film were studied under variable loads and shearing velocities by the molecular dynamics (MD) method. The results showed irreversible deformation of MoS2 was caused by heavy load or high shear velocity during the friction process and the interlayer velocity changed from a linear to a ladder-like distribution; thus, the number of shear surfaces and the friction coefficient decreased. The low friction coefficient caused by heavy load or high velocity could be maintained with a decrease in load or velocity. For a solid MoS2 lubrication film, the number of shearing surfaces should be reduced as much as possible and the friction pair should be run under heavy load or high shear velocity for a period of time in advance; thus, it could exhibit excellent frictional properties under other conditions. The proposed friction mechanism provided theoretical guidance for experiments to further improve the frictional properties of MoS2.Deformation of MoS2 layers directly leads to decrease in potential and ultimately leads to decrease in friction coefficient. 相似文献
993.
A large number of antibiotics are entering the aquatic environment accompanying human and animal excreta, which will threaten the survival of aquatic organisms and even human health. It has been found that binary mixtures of aminoglycoside (AG) exhibit additive action and can be evaluated well by a classical model, concentration addition (CA) in our past study. Therefore, to investigate the toxicity interaction within multi-component mixtures of AG antibiotics, five antibiotics, kanamycin sulfate (KAN), neomycin sulfate (NEO), tobramycin (TOB), streptomycin sulfate (STS), and gentamicin sulfate (GEN), were selected to construct five-component mixture systems by a uniform design ray method. The toxic effects (luminescence inhibition) of single antibiotic and five-antibiotic mixture systems towards a photobacterium Vibrio qinghaiensis sp.-Q67 (V. qinghaiensis) in different exposure time (0.25, 2, 4, 8, and 12 h) were determined by the time-dependent microplate toxicity analysis method. The concentration-effect data were fitted by a nonlinear least square method, toxicity interaction within mixture systems was analyzed by a CA model, and the interaction intensity was characterized by deviation from the CA model (dCA). Besides, the toxicity mechanism of five antibiotics and their five-component mixtures to V. qinghaiensis was analyzed by electron microscopy. The results show that toxicity of five antibiotics and their five-component mixture systems to V. qinghaiensis is time-dependent and has strong long-term toxicity. Different from binary AG antibiotic mixture systems, five-antibiotic mixture systems exhibit obviously time-dependent synergism. In addition, toxicity of the five-antibiotic mixtures can be 1.4 times higher than that of the mixtures without synergisms at the same concentration level. According to dCA, synergism intensity (dCA) curves of rays move slowly from the high concentration region to the medium or lower one and the maximum dCA values also increase, decrease, or first increase, then decrease with the lengthening of exposure time. The inhibition activity and synergism intensity of mixture rays have good correlation with the concentration ratios of STS, the key component for synergism. The cell morphology of V. qinghaiensis indicates the strong toxicity of five antibiotics and their mixture rays is not due to the destruction of cell structure, but the inhibition of the light-emitting activity of the photobacterium.There was time-dependent synergism in the five-component mixture systems of five antibiotics, which induced by STS. 相似文献
994.
Hydrophobic clinoptilolite (CP) was successfully synthesized via a silanization method using methyltriethoxysilane (MTS) or diethoxydimethylsilane (DMTS) as silane coupling agents. The structural and textural properties of the resultant hydrophobic CP were characterized using various methods. The effect of the amount of MTS or DMTS additive on the induction (nucleation) and growth of CP were also investigated, and the apparent activation energy values for induction and growth periods were calculated, suggesting that the induction period is kinetically controlled, while the rapid growth process is thermodynamically controlled. Meanwhile, DMTS modification enhanced the hydrophobicity of CP compared with its MTS-modified counterpart and pure CP. Finally, various ZnO-supported CPs were used as photocatalysts for the removal of crystal violet from aqueous solution, demonstrating that ZnO/hydrophobic CP has the largest adsorption capacity and best removal performance. These results suggest that hydrophobic CP, as an adsorbent or support, has the most potential for applications in separation and catalysis.One-step synthesis of hydrophobic CPs was demonstrated, in which the kinetically-controlled induction period and thermodynamically-based rapid growth process were elucidated. 相似文献
995.
Lu Zheng Yucai Lin Donghui Wang Jipeng Chen Ke Yang Binbin Zheng Weibin Bai Rongkun Jian Yanlian Xu 《RSC advances》2020,10(41):24241
Correction for ‘Facile one-pot synthesis of silver nanoparticles encapsulated in natural polymeric urushiol for marine antifouling’ by Lu Zheng et al., RSC Adv., 2020, 10, 13936–13943, DOI: 10.1039/D0RA02205E.The authors regret that an incorrect version of Fig. 2 was included in the original article. The correct version of Fig. 2 is presented below.Open in a separate windowFig. 2TEM images of PUL/AgNPs (a–d); EDS of AgNPs (e); UV-vis spectra of AgNPs (f); FT-IR spectra of urushiol (U); PUL/AgNPs (g); XRD image of AgNPs (h).The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
996.
BinXiao Wei XiaoTong Yi YongJian Xiong XinJing Wei YaDong Wu YuDong Huang JinMei He YongPing Bai 《RSC advances》2020,10(35):20588
Due to the development of the aerospace technology, the requirements for composite materials have become stricter. Thus, in this work, a completely novel technology, which has not been reported elsewhere, was used to prepare a composite of a carbon fiber-reinforced epoxy resin (CFRP) and ethylene-propylene-diene rubber (EPDM), which was denoted as CFRP/EPDM; CFRP and EPDM are commonly used as a shell and heat insulation layer, respectively, in the solid rocket industry. The composite system had good adhesive ability, as confirmed by the 90° peel strength test, even though the EPDM rubber is non-polar in nature. Additionally, the adhesive mechanism between CFRP and EPDM was determined using scanning electron microscopy (SEM). Thermogravimetric analysis (TGA) indicated that the Td10% value of the CFRP/EDPM composite was slightly higher than that of CFRP. According to the nuclear magnetic resonance (NMR) spectroscopy results of the EPDM rubber and the interlaminar shear strength (ILSS) of CFRP, we can conclude that the co-curing method will not damage the properties of CFRP and EPDM.The CFRP/EPDM composite was prepared by a one-step co-curing method, which was very convenient and energy effective. 相似文献
997.
目的了解社区糖尿病患者糖尿病足相关运动锻炼行为状况,分析影响因素。方法采用糖尿病足知识问卷、糖尿病足自我锻炼健康信念问卷、糖尿病足自我锻炼行为问卷,对上海市某社区糖尿病患者209例进行调查。结果社区糖尿病患者糖尿病足相关运动锻炼行为得分率60.53%~72.48%;糖尿病足相关知识和健康信念是运动锻炼的主要影响因素(P<0.05,P<0.01)。结论社区糖尿病患者的运动锻炼行为不理想,需加强健康教育,提高其知识水平及健康信念,促进其锻炼的健康行为,有效预防糖尿病足。 相似文献
998.
目的 系统评价以夫妻为中心的心理干预对孕产妇心理状况的影响。
方法 检索PsycINFO、PubMed、Embase、CINAHL、Web of Science、The Cochrane Library、中国知网和万方数据库,纳入以夫妻为中心的心理干预对孕产妇心理状况影响的随机对照试验。采用RevMan5.4软件进行Meta分析,通过敏感性分析和亚组分析探索异质性的可能来源,并评估结果的稳健性。
结果 共纳入17篇文献,包括3 123名孕产妇。Meta分析结果显示,以夫妻为中心的心理干预显著降低抑郁症状发生率[RR=0.45,95%CI(0.33,0.60),P<0.05],并降低孕产妇抑郁、焦虑、压力水平(均P<0.05)。干预跨度的亚组分析结果显示,分娩前干预组、分娩前后干预组与对照组抑郁、焦虑得分的差值存在统计学差异(均P<0.05)。
结论 以夫妻为中心的干预对改善孕产妇的抑郁、焦虑和压力状况具有积极作用,但由于各研究间的异质性,有待大样本、多中心、高质量的随机对照研究进一步验证其效应量。 相似文献
999.
Ahmad M. Eweida M.D. Werner Lang M.D. Marweh Schmitz M.D. Raymund E. Horch M.D. 《Microsurgery》2013,33(5):391-395
Interdisciplinary approaches with infrainguinal bypass grafts and free flaps between the plastic and vascular surgery may well offer an opportunity for diabetic patients with peripheral vascular disease to salvage their critically affected limbs. A free flap transfer combined with an autologous vein graft can cover large tissue defects and simultaneously improve distal perfusion even in patients with arterial occlusive disease. We are presenting a case of bypass‐free radial forearm flap used to cover a foot defect in an old diabetic patient with peripheral arterial disease. The flap perfusion deteriorated significantly during the early postoperative period. The patient was brought back to the operating room with acute thrombosis of the popliteal‐radial venous graft and the arterial pedicle of the flap. The flap was salvaged by thrombectomy and creation of an additional arteriovenous fistula at the distal arterial pedicle. The procedure improved the flap perfusion and decreased the high internal resistance that was noticed in the flap when trying to flush the radial artery during the revision surgery and was evident by continuous wave ‐Doppler sonography. The successful salvage of the flap in the presented case and the convenient long‐term follow up suggest that this technique may be safe and helpful as a last effort to salvage a bypass‐free flap with a suspected high internal resistance. © 2013 Wiley Periodicals, Inc. Microsurgery 33:391–395, 2013. 相似文献
1000.
Helmut Schiffl Susanne M. Lang Rainald Fischer 《International urology and nephrology》2013,45(5):1389-1396