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31.
饮食服务业从业人员乙型肝炎病毒感染动态研究   总被引:1,自引:0,他引:1  
目的为了解泰安市饮食服务业从业人员乙型肝炎病毒感染状况。方法应用ELISA方法在1995~1999年对53434名饮食服务业从业人员进行了血清HBsAg、抗-HBc、HBeAg和抗-HBe检测。结果1995~1999年饮食服务业从业人员血清HBsAg、抗-HBc、HBeAg和抗-HBe总阳性率呈逐年下降趋势,依次为4.41%、3.88%、3.46%、2.86%和2.50%,其差异有显著意义(χ  相似文献   
32.
Wang  Jue  Wu  Jiang  Xu  Minghuo  Gao  Quanwen  Chen  Baoguo  Wang  Fang  Niu  Hao  Song  Huifeng 《Lasers in medical science》2021,36(6):1275-1282

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients’ satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P?<?0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

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33.
Smokers are at a higher risk of delayed union or nonunion after fracture repair. Few specific interventions are available for prevention because the molecular mechanisms that result in these negative sequelae are poorly understood. Murine models that mimic fracture healing in smokers are crucial in further understanding the local cellular and molecular alterations during fracture healing caused by smoking. We exposed three murine strains, C57BL/6J, 129X1/SvJ, and BALB/cJ, to cigarette smoke for 3 months before the induction of a midshaft transverse femoral osteotomy. We evaluated fracture healing 4 weeks after the osteotomy using radiography, micro-computed tomography (μCT), and biomechanical testing. Radiographic analysis demonstrated a significant decrease in the fracture healing capacity of smoking 129X1/SvJ mice. μCT results showed delayed remodeling of fracture calluses in all three strains after cigarette smoke exposure. Biomechanical testing indicated the most significant impairment in the functional properties of 129X1/SvJ in comparison with C57BL/6J and BALB/cJ mice after cigarette smoke exposure. Thus, the 129X1/SvJ strain is most suitable in simulating smoking-induced impaired fracture healing. Furthermore, in smoking 129X1/SvJ murine models, we investigated the molecular and cellular alterations in fracture healing caused by cigarette smoking using histology, flow cytometry, and multiplex cytokine/chemokine analysis. Histological analysis showed impaired chondrogenesis in cigarette smoking. In addition, the important reparative cell populations, including skeletal stem cells and their downstream progenitors, demonstrated decreased expansion after injury as a result of cigarette smoking. Moreover, significantly increased pro-inflammatory mediators and the recruitment of immune cells in fracture hematomas were demonstrated in smoking mice. Collectively, our findings demonstrate the significant cellular and molecular alterations during fracture healing impaired by smoking, including disrupted chondrogenesis, aberrant skeletal stem and progenitor cell activity, and a pronounced initial inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
34.
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.  相似文献   
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38.
微波体模   总被引:9,自引:1,他引:9  
用水、盐,聚氯乙烯粉和羧甲基纤维钠四种材料配制成一种适用的微波体模(模拟肌肉组织)。该体模的复介电系数在300~2500MHz范围内与实际人体肌肉组织的误差≤5%。这种体模的优点是材料立足国内,价廉,室温下配制,使用方便。本文也给出这种体模的温度特性,稳定性和热学特性,供电磁场生物效应和微波热疗等研究使用。  相似文献   
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目的 观察异丙酚和咪唑安定在体外循环麻醉中对术前和术中的酸碱度的影响.方法 40例先天性心脏病患者随机分为两组(异丙酚组、咪唑安定组),监测手术前、主动脉阻断10 min和复温至31℃时血气指标等的动态变化.结果与手术前比,主动脉阻断10 min和复温后,血液pH、PaCO2、HCO3-、BEB两组均有明显变化(P<0.05),但两组间差异无显著性(P>0.05).结论异丙酚和咪唑安定在体外循环麻醉中其对酸碱度无明显的影响.  相似文献   
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