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1.
A recently introduced setup to measure the dynamic interfacial tension of expanding drops was used to compare the adsorption behaviour of a series of lipids at the electrified water∣dichloroethane interface. Phospholipids with saturated carbon chains of different length (DMPC, DPPC, DSPC, DAPC, DBPC), an unsaturated phospholipid (DOPC) and an ethanolamine (DSPE) were compared. It was found that the adsorption decreases with increasing chain length. Also, the increase of the flow rate reduces the degree of adsorption effectively. On the timescale of the experiments, the DSPE, DAPC and DBPC adsorption showed no potential dependence, whereas the adsorption of DOPC was stronger than that of the saturated lipids. Adsorption was modelled using the Langmuir adsorption isotherm; the potential dependence of adsorption is discussed.  相似文献   
2.
Background Dentin-bonding systems contain sensitizing acrylates. They are increasingly used in dentistry, but only few cases of allergy have been encountered. Objective This study reports observations on eleven patients sensitized by acrylates in dentin-bonding compounds. Furthermore, the composition of dentin-bonding products was analysed and compared with the information given in the material safety data sheets. Methods Patch testing was performed to reveal allergic contact dermatitis, and chamber provocation tests to reveal possible respiratory sensitivity. Gas chromatography/mass spectrometry was used to analyse the chemical composition of the bonding products. Results The most common sensitizer in our material of eleven patients was 2-hydroxyethyl methacrylate (2-HEMA). Another putative sensitizer, BIS-GMA, used in dentin adhesives, did not cause sensitization. The typical allergic dermatitis localized to the fingertips (pulpitis). Seven of the eleven patients also developed paresthesia of the fingertips. One patient with positive patch test reactions to (meth)acrylates had pharyngitis hut no skin symptoms. One patient was sensitized because she had been patch tested with too high a concentration (undiluted) of dentin-bonding components. Material safety sheets gave inaccurate or wrong information about the contents. Conclusion Dentin-bonding acrylates are strong sensitizers, and even a single exposure may sensitize.  相似文献   
3.
复发性胶质瘤再手术治疗的探讨   总被引:2,自引:0,他引:2  
目的 探讨复发性胶质瘤患者再手术的效果。方法 对22例复发性胶质瘤患者再手术前的功能状态、两次手术间隔时间及手术切除的程度与术后存活期等资料进行临床和统计学分析。结果 第二次手术前生活能自理或半自理的病人(Kamofsky计分≥60)平均生存期约16月,生活不能自理的病人(Kamofsky计分〈60)平均生存期约6月(P〈0.01)。两次手术间隔时间大于1年者平均生存期约17月,间隔时间小于半年者平均生存期约6月(P〈0.01)。手术肿瘤全切除者平均生存期约15月,次全切除者平均生存期约10月(P〈0.05)。结论 术前功能情况好,手术间隔时间大于1年及术中全切肿瘤者再手术治疗可获得较好效果。  相似文献   
4.
BACKGROUND: In several clinical studies, topical calcineurin inhibitors have been shown to be effective in the treatment of atopic dermatitis (AD). They target signaling pathways that control gene expression, particularly the expression of cytokines. OBJECTIVE: We examined the cellular infiltrate in skin lesions of 10 patients with AD and characterized the cytokine pattern expressed by the infiltrating cells before and after short-term topical therapy with tacrolimus 1% ointment. METHODS: Skin biopsies were examined for histologic alterations (hematoxylin and eosin staining), composition of the cellular inflammatory infiltrate (immunofluorescence), and cytokine expression (ribonuclease protection assay, ELISA, immunofluorescence) before as well as 1 and 3 weeks after initiation of tacrolimus therapy. For comparison, biopsies from nonlesional AD and normal skin were analyzed. Systemic immunologic effects were assessed by analyzing peripheral blood leukocytes (immunofluorescence) as well as in vitro stimulated pan-T-cell cytokine production (ELISA). RESULTS: All patients showed a significant improvement of their skin lesions associated with a marked regression of spongiosis, acanthosis, and density of the cellular infiltrate in the dermis. The last was a result of reduced infiltration of T cells, B cells, and eosinophils. In contrast, the numbers of mast cells did not change. Moreover, the expression of the T H 2 cytokines IL-5, IL-10, and IL-13 in CD4 + T cells was reduced after therapy. Interestingly, tacrolimus therapy was also associated with a reduction of CD8 + T cells expressing the T H 1 cytokine IFN-gamma. Furthermore, the numbers of epidermal CD1a + dendritic cells increased after treatment. In the peripheral blood, a decrease of granulocytes (eosinophils and neutrophils) but no changes in the distribution of lymphocyte subpopulations were noticed. CONCLUSION: Topical tacrolimus treatment has anti-inflammatory effects on AD skin as indicated by reduced infiltration of cytokine expressing inflammatory cells. No evidence for drug-induced systemic immunosuppression was obtained.  相似文献   
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6.
Summary With 158 victims, the fire on board the Scandinavian Star was one of the world's worst ferry disasters. A team of identification experts, including dentists, were employed to secure evidence for identification and to remove the victims from the ferry. Four parallel teams, each with 2 dentists, examined and autopsied the victims at the Institute of Forensic Medicine, University of Oslo. Using the INTERPOL Disaster Victim Identification forms and aided by computers, all victims were identified within 17 days. Dental identity could be established in 107 cases (68%).  相似文献   
7.
防风色原酮成分群的分离制备及其含量分析   总被引:2,自引:0,他引:2  
目的:以6种色原酮类成分的含量比较研究防风色原酮有效部位的分离、纯化方法。方法:HPLC梯度洗脱法同时测定6种色原酮类成分的含量,色谱柱为Kromasil C18柱,流动相为甲醇-0.1%磷酸水梯度洗脱,检测波长254 nm,流速1.0 mL·min-1,柱温35 ℃。结果:6个成分在测定范围内线性关系较好(r>0.999 5),平均回收率均大于97%,RSD均小于5%。各样品含量差异显著。结论:所建立的方法准确、可靠,防风色原酮成分群的制备方法以水煎醇沉树脂分离结合硅胶纯化法较好。  相似文献   
8.
目的:建立测定血清中硒的新方法。方法:应用Triton X-100稀释样品,横向塞曼石墨炉原子吸收光谱法直接测定样品中痕量硒。结果:选定了最佳测量条件,该方法的灵敏度、精密度均能满足检测工作的需要。本法对硒的最低检出量为14.7 pg,回收率在90%~102%之间。结论:本法简便、快速、准确,灵敏度和精密度高,适用于血清中硒的测定。  相似文献   
9.
萸黄连为“相反为制”改变饮片药性的代表性炮制品之一,首载于《韩氏医通》,炮制方法为吴茱萸汁与净黄连拌匀闷润后炒干即得,即通过吴茱萸制黄连在保留黄连泻火解毒功效的基础上降低了黄连的苦寒之性,使黄连寒而不滞,可清气分湿热,对肝气犯胃、呕吐吞酸等病症有良好疗效。作为相反为制、药汁制的代表品种,萸黄连饮片收录于2020年版《中华人民共和国药典》和多个地方炮制规范中,其炮制工艺研究及优选一直备受关注。现代研究表明,萸黄连除含有小檗碱、药根碱、巴马汀等黄连中的成分外,还含有吴茱萸碱、吴茱萸次碱、柠檬苦素等吴茱萸中的成分,具有抗炎、抗菌、抗肿瘤等药理活性。该文对近20年萸黄连相关的研究报道进行整理归纳,从萸黄连的炮制历史及工艺、药效药性、质量评价和临床应用等方面进行综述,发现萸黄连在各省市炮制规范收载的炮制方法及标准差异较大,主要涉及吴茱萸汁的制备方法、吴茱萸汁的用量和炮制终点的判断标准等方面;此外,不同研究期间萸黄连炮制前后主要成分的变化情况差异较大,推测与萸黄连的炮制工艺和质量标准不同有关。该综述可为完善萸黄连的质量评价体系提供参考。  相似文献   
10.
ObjectiveTo investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI.DesignA prospective observational study using continuous twenty-four-hour Holter monitoring.SettingInpatient rehabilitation unit of a university research hospital and patient home setting.ParticipantsFifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale.Outcome measuresComparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring.ResultsBradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1–C8) and thoracic (T1–T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months.ConclusionsAt the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.  相似文献   
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