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91.
目的 分析血药浓度监测(TDM)优化美罗培南治疗老年脓毒血症的临床疗效。方法 选择2021年1月至2022年2月我院收治的脓毒血症老年患者64例,随机分为对照组31例,观察组33例。对照组接受常规美罗培南治疗,观察组接受TDM优化美罗培南,对比治疗1周后两组病情变化、生化指标、肺功能、实验室指标与不良反应等。结果 治疗1周后,观察组APACHEⅡ评分/SOFA评分低于对照组(P<0.05),观察组肌酐、胆红素、AST、ALT、EVLW、PVPI下降(P<0.05),观察组白细胞、降钙素原、C-反应蛋白水平低于对照组(P<0.05),观察组美罗培南药物谷浓度与峰浓度高于对照组(P<0.05),观察组PK/PD参数最低抑菌浓度(MIC)为1、2、4时血清药物浓度高于MIC的时间(%T>MIC)优于对照组(P<0.05)。结论 65岁以上老年脓毒血症患者,实施TDM优化美罗培南治疗,可降低病情严重水平,调控机体生化指标、炎症指标,提高药物抗菌活性、药物有效浓度,改善患者肺功能,减少药物不良反应,具有临床意义。 相似文献
92.
Yanan Zhao Xianming Xu Yulong Wang Tong Liu Hongpeng Li Yongjun Zhang Libo Wang Xiuhui Wang Simeng Zhao Yi Luo 《RSC advances》2022,12(33):21111
The polymerization of α-olefins catalyzed by zirconium metallocene catalyst was systematically studied through experiments and density functional theory (DFT) calculations. Having achieved an agreement between theory and experiment, it was found that the effect of the catalyst ligand on the C C insertion reaction was significantly greater than that on the β-H elimination reaction. Therefore, the molecular weight of polymers can be increased by improving the activity of the C C insertion. In addition, in comparison with propylene, the chain length of α-olefins can directly affect the stereotacticity of polymerization products, owing to steric hindrance between the polymer chain and monomer.The polymerization of α-olefins catalyzed by zirconium metallocene catalyst was systematically studied through experiments and density functional theory (DFT) calculations. 相似文献
93.
94.
目的:探讨新生儿上消化道出血临床治疗效果。方法:采用回顾性分析的方法,分析我院收治的新生儿上消化道出血病例临床资料,依据治疗方式不同分为对照组(常规治疗组)30例和观察组[酚磺乙胺注射液(止血敏)联合磷酸铝凝胶(吉福士)治疗组]50例。结果:观察组患儿止血时间、胃管引流无血性液天数、粪便转黄天数、隐血试验阴性天数均明显低于对照组,同时观察组的治疗效果上明显的好于对照组,P<0.05,差异均有统计学意义。结论:止血敏联合吉福士治疗新生儿上消化道出血,患儿止血效果明显,值得临床推广应用。 相似文献
95.
目的探讨含有各种浓度硫化氢(H2S)的HST(H2S St.Thom asⅡsolutions)液对大鼠离体心脏的保存作用。方法将32只SD大鼠随机平均分为4组,分别用托马斯(St.Thom asⅡsolutions,STH)液(Ⅰ组)、含4×10-2mmol/L NaHS的HST液(Ⅱ组)、含4×10-1mmol/L NaHS的HST液(Ⅲ组)和含4mmol/L NaHS的HST液(Ⅳ组)对心脏进行保存。采用Langendorff心脏灌注和工作模型装置进行心脏功能测定,比较6 h后心功能恢复率以及能量变化、心肌含水量,观察心肌超微结构改变。结果心脏保存6 h后,Ⅳ组左心室功能损伤严重,Ⅱ、Ⅲ组左心室功能损伤较轻,其中Ⅲ组最轻。Ⅲ组冠状动脉流量(CF)恢复率较Ⅰ、Ⅳ组好;Ⅰ组心肌中ATP、乳酸(LD)、糖原含量及心肌含水量与其它3组比较,差异有统计学意义;Ⅳ组心脏复跳时间较Ⅰ组为长;心肌超微结构Ⅲ组损伤最轻;Ⅲ组心肌保存良好。结论HST保存液对大鼠心脏的保存在6 h内有明显的保护作用,效果优于STH液;含4×10-1mmol/L NaHS的HST液保存效果较好,而高浓度H2S对心肌有损害作用。 相似文献
96.
Yu Shi Shiwei Wang Yiming Li Fan Yang Hongbo Yu Yuting Chu Tong Li Hongfeng Yin 《Materials》2022,15(9)
A series of NiP-x/Al2O3 catalysts containing different ratio of metallic nickel to nickel phosphides, prepared by varying Ni/P molar ratio of 4, 3, 2 through a co-impregnation method, were employed to investigate the synergistic effect of metallic nickel-nickel phosphides in dry methane reforming reaction. The Ni/Al2O3 catalyst indicates good activity along with severe carbon deposition. The presence of phosphorus increases nickel dispersion as well as the interaction between nickel and alumina support, which results in smaller nickel particles. The co-existence of metallic nickel and nickel phosphides species is confirmed at all the P contained catalysts. Due to the relative stronger CO2 dissociation ability, the NiP-x/Al2O3 catalysts indicate obvious higher resistance of carbon deposition. Furthermore, because of good balance between CH4 dissociation and CO2 dissociation, NiP-2/Al2O3 catalyst exhibits best resistance of carbon deposition, few carbon depositions were formed after 50 h of dry methane reforming. 相似文献
97.
Solomon Kerealme Yeshanew Chunguang Bai Qing Jia Tong Xi Zhiqiang Zhang Diaofeng Li Zhizhou Xia Rui Yang Ke Yang 《Materials》2022,15(9)
The hot workability behavior of antibacterial Ti6Al4V-5Cu alloy was investigated using a hot compression experiment in the temperature range of 790–1040 °C and strain rate of 10−3–10 s−1 with a strain of 0.4. The deformation behavior of the alloy was characterized by Gleeble 3800 compression experiment, and the relationship among deformed microstructures and deformation parameters was established. The deformations of Ti6Al4V-5Cu alloy were temperature and strain rate-dependent. Higher temperature and lower strain rate made power dissipation efficiency (η) increase and reach 89%. The activation energies (Q) in the dual-phase (α + β) and single β phase regions were calculated as 175.43 and 159.03 kJ mol−1, respectively. In the dual (α + β) phase region, with an increase in strain rate, flow-softening behavior was dominated, however in the single β phase region such as processing at 940 °C. Flow stress increased slightly in which work-hardening behavior was dominated (especially between strain rates of 10−3–1 s−1). The deformation at various conditions exhibited different stress-strain profiles, providing an insight that work hardening and flow softening coexisted in Ti6Al4V-5Cu alloy. The relative intensity of oscillatory change in flow stress profile decreased as the strain rate decreased. The hot workability of Ti6Al4V-5Cu alloy was also accessed from the viewpoint of the sub-grain structure. 相似文献
98.
Xuanshuo Zhang Hongbo Li Sheng Li Yongfa Ding Hubiao Zhang Yufei Tong Shudong Hua 《Materials》2022,15(9)
In this study, the silica fume replacement rate, fly ash replacement rate, and curing temperature were regarded as the independent variables, and the compressive and flexural strengths were regarded as the response values. The response surface method was used to construct the response surface polynomial regression model and obtain the optimal preparation parameters of a steel slag cement-based gel slurry (SCGS). The univariate and multivariate effects on the SCGS’s strength were investigated via analysis of variance and a three-dimensional surface model, and the hydration products and strength development law were characterized via scanning electron microscopy and X-ray diffraction. The actual compressive strengths at 3 and 28 d of age were 31.78 and 53.94 MPa, respectively, which were close to the predicted values (32.59 and 55.81 MPa, respectively), demonstrating that the optimized strengths were accurate and reliable. Further, the hydration reaction rate of SiO2 in the silica fume and the physical filling effect of the inert components of fly ash and steel slag under the optimal parameters were the key factors for the early strength of the material. Moreover, continuous C3S hydration in steel slag and the continuous excitation of the volcanic ash properties of fly ash were important factors for the later strength. 相似文献
99.
Y. Tong E. Orango M. Nakalembe P. Tonui P. Itsura K. Muthoka M. Titus S. Kiptoo A. Mwangi J. Ongecha R. Tonui B. Odongo C. Mpamani B. Rosen A. Moormann S. Cu-Uvin J. A. Bailey C. I. Oduor A. Ermel C. Yiannoutsos B. Musick E. Sang A. Ngeresa G. Banturaki A. Kiragga J. Zhang Y. Song S. Chintala R. Katzenellenbogen P. Loehrer D. R. Brown 《Annals of medicine》2022,54(1):1202
The East Africa Consortium was formed to study the epidemiology of human papillomavirus (HPV) infections and cervical cancer and the influence of human immunodeficiency virus (HIV) infection on HPV and cervical cancer, and to encourage collaborations between researchers in North America and East African countries. To date, studies have led to a better understanding of the influence of HIV infection on the detection and persistence of oncogenic HPV, the effects of dietary aflatoxin on the persistence of HPV, the benefits of antiretroviral therapy on HPV persistence, and the differences in HPV detections among HIV-infected and HIV-uninfected women undergoing treatment for cervical dysplasia by either cryotherapy or LEEP. It will now be determined how HPV testing fits into cervical cancer screening programs in Kenya and Uganda, how aflatoxin influences immunological control of HIV, how HPV alters certain genes involved in the growth of tumours in HIV-infected women. Although there have been challenges in performing this research, with time, this work should help to reduce the burden of cervical cancer and other cancers related to HIV infection in people living in sub-Saharan Africa, as well as optimized processes to better facilitate research as well as patient autonomy and safety.
KEY MESSAGES
- The East Africa Consortium was formed to study the epidemiology of human papillomavirus (HPV) infections and cervical cancer and the influence of human immunodeficiency virus (HIV) infection on HPV and cervical cancer.
- Collaborations have been established between researchers in North America and East African countries for these studies.
- Studies have led to a better understanding of the influence of HIV infection on the detection and persistence of oncogenic HPV, the effects of dietary aflatoxin on HPV detection, the benefits of antiretroviral therapy on HPV persistence, and the differences in HPV detections among HIV-infected and HIV-uninfected women undergoing treatment for cervical dysplasia by either cryotherapy or LEEP.
100.
为了进一步探讨植物多糖与膜磷脂的关系,采用毛细管柱气相色谱法观察到在茯苓多糖(PPS),刺五加多糖(ASPS)与S_180细胞一同温育24h后,S_180细胞膜中性脂的脂肪酸组成和不饱和性均未有明显变化。磷脂的脂肪酸组成发生明显改变,花生四烯酸(C_(20∶4),P<0.05)和豆蔻酸(C_(14∶0),P<0.01)的含量降低。上述结果与氨甲喋呤作用相似。讨论了膜磷脂脂肪酸组成变化的意义,认为在PPS、ASPS的抗肿瘤机理中,细胞膜磷脂生化特性的改变是重要环节。 相似文献