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991.
目的:探讨阿托伐他汀钙对颈动脉粥样硬化斑块及CRP的影响。方法选择76例颈动脉粥样硬化斑块患者,采用数字表法随机分为观察组和对照组各38例,对照组仅给予常规治疗,观察组在对照组基础上给予阿托伐他汀钙治疗,比较治疗后两组颈动脉粥样硬化斑块的面积大小及血浆CRP变化情况。结果观察组治疗后斑块大小为(0.069±0.021)cm2,颈动脉内膜中层厚度(IMT)为(1.29±0.28)mm,均显著小于治疗前(t=7.538、7.132,均P<0.05),亦均明显小于对照组治疗后(t=7.131、6.372,均P<0.05);观察组治疗后CRP为(3.54±1.92)mg/L,明显低于治疗前,治疗前后差异有统计学意义(t=6.831,P<0.05),且明显低于对照组治疗后(t=7.125,P<0.05)。结论对于颈动脉粥样硬化斑块的患者而言,应用阿托伐他汀钙治疗,不仅可有效缩小斑块面积,还可降低CRP,值得在临床中进一步应用。 相似文献
992.
目的 比较依度沙班与低分子肝素预防骨科大手术后静脉血栓栓塞(venous thromboembolism,VTE)的有效性和安全性。方法 检索Cochrane Library、PubMed、EMBASE、中国知网、万方和维普科技期刊等数据库。收集依度沙班与低分子肝素预防骨科大手术后VTE随机对照试验。应用RevMan 5.3.5软件进行分析。结果 最终纳入5项研究,涉及2 585例患者。依度沙班组总VTE发生率[RR=0.47,95% CI(0.38,0.56),P<0.000 01]、无症状性深静脉血栓发生率[RR=0.47,95% CI(0.31,0.71),P=0.000 4]均低于低分子肝素组。依度沙班组总出血事件发生率高于低分子肝素组[RR=1.22,95% CI(1.01,1.49),P=0.04]。亚组分析发现依度沙班不同剂量组总VTE发生率均低于低分子肝素组,15 mg组、30 mg组与低分子肝素组总出血事件发生率差异均无统计学意义。结论 依度沙班预防骨科大手术后VTE优于低分子肝素,但增加了总出血事件发生率。15,30 mg依度沙班可能为较安全剂量。 相似文献
993.
Chuan Xie Siyu Zhang Wei Zhang Chunxia Wu Can Yong Yuhao Sun Zhengxing Zeng Qian Zhang Zixin Huang Tian Chen Yuanyuan Zhang 《Chemical biology & drug design》2020,96(2):836-849
The issue of antibiotic resistance is becoming progressively serious these days, and the feasible solution to address it is to develop and discover novel antibiotics. The diterpene natural pleuromutilin is a prominent candidate for its special mode of action by inhibiting protein synthesis. In this study, a series of novel pleuromutilin derivatives with chalcone moiety was designed and synthesized, and their antibacterial activities were assessed in vitro. As suggested from the results, most of compounds exhibited potent activities against two methicillin‐resistant Staphylococcus aureus (MRSA) ATCC 33591 and 43300. The further modification of the chalcone structure, aza‐cyclic derivatives were afforded and then assessed, and potent activities against the tested strains were reported. The preliminary docking studies were conducted to explore the interactions between target molecules and binding site. 相似文献
994.
目的: 通过共价结合制备肝素-藤黄酸接枝物(GA-Hep), 考察GA-Hep胶束的性质及体外抗肿瘤活性。方法: 通过酰胺键将藤黄酸与肝素连接制备GA-Hep, 透射电镜观察胶束形貌、纳米粒度仪分析胶束的粒径及Zeta电位、荧光分光光度计检测临界聚集浓度(critical aggregation concentration, CAC)、噻唑蓝(MTT)法考察自组装胶束体外对肺癌细胞A549细胞的抑制作用。结果: GA-Hep胶束为球形, 平均粒径(163±1.16)nm, Zeta电位为(-29±0.91)mV, 取代度为(44.50±0.15)%, CAC值为(0.004±0.000 61)mg·mL-1, 体外抗肿瘤试验结果表明GA-Hep对A549细胞的IC50为(31.22±0.14)μg·mL-1。结论: 该研究表明GA-Hep具有较高的载药量, 并形成稳定的胶束, 同时保留了藤黄酸的抗肿瘤活性。 相似文献
995.
目的 比较利伐沙班和低分子肝素在预防全髋关节置换术术后对患者深静脉血栓(DVT)形成的影响及疗效。方法 126例行全髋关节置换术的患者随机分为利伐沙班组和低分子肝素组。低分子肝素组(n=70)术前12 h或术后24 h给予低分子肝素注射液,皮下注射,40 mg,1 次·d-1,连续给药14 d。利伐沙班组(n=56)术后6~8 h给予利伐沙班口服,10 mg,1次·d-1,连续给药35 d。观察2组术中出血量和术后引流量,比较2组的安全性指标以及术后DVT的发生率。结果 2组术中出血量、术后引流量、术后下肢DVT发生率比较差异无统计学意义(P>0.05)。利伐沙班组增加了患者术后出血、切口感染、切口不愈合或延期愈合等不良事件的风险,与低分子肝素组比较差异有统计学意义(P<0.05)。结论 在全髋关节置换术后预防DVT方面,利伐沙班和低分子肝素的疗效相似,但术后伤口并发症发生率明显高于低分子肝素,使用利伐沙班的安全性需要进一步验证。 相似文献
996.
The global use of petroleum hydrocarbons as raw materials and an energy source in industry results in serious environmental, health, and ecological problems. Consequently, there is growing interest in the development of technologies for the rehabilitation of contaminated areas. This study was undertaken in order to determine the effect of different phytostabilising materials (compost, bentonite, and CaO) on the trace element content in soil contaminated with unleaded petroleum 95 (0, 2.5, 5, and 10 cm3 kg−1 of soil). The doses of petroleum applied to the soil were based on the previously conducted preliminary experiment. The highest petroleum dose (10 cm3 kg−1 of soil) significantly reduced the chromium, zinc, and cobalt contents in the soil. Petroleum increased the cadmium, lead, nickel, and copper contents in the soil. The materials used for phytostabilisation (compost, bentonite, calcium oxide) had a significant effect on the trace element content in the soil. The application of mineral materials (bentonite and calcium oxide) was more effective than the application of compost, compared to the control series (without soil amendments) as they reduced the contents of cadmium, chromium, nickel, and cobalt in the soil to the greatest extent. The reduction effect of bentonite and calcium oxide on the content of these trace elements in the soil was stronger than compost. 相似文献
997.
This paper addressed the issues of both direct and indirect synthesis of Ni aluminides by pack cementation (pure Ni and IN 718 superalloy). On the Al-Ni diffusion twosome under pressure, at temperatures below and above the Al melting temperature, the appearance and evolution of diffusion porosity because of the Kirkendall–Frenkel effect manifestation was highlighted. It has been confirmed that, as the temperature rises above the Al melting temperature, the porosity decreases. Nickel-based superalloys, and in particular IN 718, significantly increase their performance by increasing the aluminides proportion in the top diffusion coating. This is made possible by changing the value of the Al and Ni weight percentage ratio in this area (noted as Al/Ni). In the case of the diffusion twosome between IN 718 and pack aluminizing mixtures, having in their composition as active components Al powder, Ferroaluminum (FeAl40) or mixtures of Al and Fe powders, at processing temperatures above the Al melting temperature, by modifying the active component of the mixture, substantial changes in the Al/Ni values were observed, as well as in the maximum %Al in the diffusion coating and of its thickness. It was found that, when switching from Al to FeAl40 or powder mixture (Al + Fe), the Al/Ni value changes between 3.43 and 1.01, from initial subunit values. The experiments confirmed that the highest %Al in the top aluminized diffusion coating, for IN 718, was obtained if the powder mixture contained 66.34 wt.% Al. 相似文献
998.
Geocell is widely used in the treatment of poor roadbed, which can restrain soil laterally and improve the stability of soil. In cold area engineering, a change in temperature can influence the mechanical properties of geocell of different materials. To study the mechanical response of geocell at low temperatures, three types of geocell strips commonly used in engineering, namely the polyethylene (HDPE), polypropylene (PP), and polyester (PET), were studied via the uniaxial tensile test at the ambient temperatures of −5 °C, −20 °C, and −35 °C, respectively. Meanwhile, the tensile strength, fracture mode, and temperature sensitivity of geocell specimens were compared. It is concluded that: (1) at low temperatures, the tensile strengths of HDPE and PET geocell strips are significantly improved, while that of the PP geocell strip is less sensitive to the temperature. (2) The PP geocell is subject to a brittle failure at all ambient temperatures. The PET geocell strip experiences a hard-ductile failure at normal temperatures of −5 °C and −20 °C. While in the tensile test at −35 °C, it is prone to brittle failure and hard-ductile failure. The HDPE geocell strip suffers from ductile failure at all ambient temperatures. (3) At low temperatures, overall, the tensile properties of the PET geocell strip is better than those of the PP and HDPE geocell strips. 相似文献
999.
Corrosion is frequently viewed as a catastrophic and unavoidable disaster in marine applications. Every year, a huge cost is incurred on the maintenance and repair of corrosion-affected equipment and machinery. In the marine environment, as-cast nickel–aluminium bronze (NAB) is susceptible to selective phase corrosion. To solve this problem, chromium-reinforced nickel–aluminium bronze was fabricated using the friction stir process (FSP) with improved microstructures and surface properties. A slurry erosion–corrosion test on as-cast and FSPed composites demonstrated that the developed surfaced composite has lower erosion and corrosion rates than the as-cast NAB alloy. The erosion–corrosion rate increased with a decrease in the impact angle from 90° to 30° for both as-cast NAB and prepared composites, exhibiting a shear mode of erosion. The specimens at impact angle 30° experienced more pitting action and higher mass loss compared with those at impact angle 90°. Due to increases in the mechanical properties, the FS-processed composite showed higher erosion resistance than the as-cast NAB alloy. Furthermore, corrosion behaviour was also studied via the static immersion corrosion test and electrochemical measurements under 3.5 wt.% NaCl solution. In a static immersion corrosion test, the FSPed composite outperformed the as-cast NAB composite by a wide margin. The FSPed composite also demonstrated a reduced electrochemical corrosion rate, as revealed by the polarization curve and electrochemical impedance spectroscopic (EIS) data. This reduced rate is attributed to the formation of a Cr oxide film over its surface in the corrosive environment. 相似文献
1000.
目的:探讨内镜下低温等离子治疗舌甲状舌管囊肿的手术方法、疗效和适应证。方法:对11例舌甲状舌管囊肿患者行内镜下低温等离子舌甲状舌管囊肿切除术,观察疗效及并发症情况。结果:1l例患者术后症状改善,无严重并发症发生,随访1-3年,无复发。结论:内镜下低温等离子治疗舌甲状舌管囊肿手术时间短,术中出血少,术后反应轻、恢复快,疗效满意。 相似文献