交叉专科护理在颧骨复合体骨折患者中的应用分析

目的:分析交叉专科护理在颧骨复合体骨折患者治疗中的作用价值,为后续临床护理提供方法参考.方法:25例颧骨复合体骨折患者于2017年1月-2019年1月期间在我科室接受治疗,患者围术期均采取眼科及口科的交叉专科护理,分析护理效果.结果:25例患者术后颜面情况恢复良好,术后并发症较少;随访6个月后患者眼球内陷等状况改善,咬合状况良好.结论:颧骨复合体骨折临床治疗中采取交叉专科治疗可明显提高治疗效果,降低术后并发症发生率,具有临床推广价值.     

四型念珠菌与抗念珠菌血清的交叉免疫反应

目的 分析4型不同念珠菌抗血清的免疫应答状况,为念珠菌疫苗的研制奠定实验基础.方法 将白色念珠菌、热带念珠菌、吉利蒙念珠菌、假热带念珠菌4型念珠菌分别超声破碎,0.5％甲醛溶液灭活,加入弗氏完全佐剂制成灭活全菌疫苗.分别在1、4、8、12周腹腔注射免疫小鼠,4周后收集小鼠抗体血清,分别按10、100、1000倍稀释,再分别加入含200μl4种念珠菌的沙氏培养液中,观察其抑菌作用.结果 所有抗体均为10倍效果最佳,1000倍基本无效.白色念珠菌抗体血清对白色念珠菌、吉利蒙念珠菌、热带念珠菌有明显的抑菌作用（P＜0.01）;热带念珠菌抗体血清对白色念珠菌和热带念珠菌有抑菌作用（P=0.01）;吉利蒙念珠菌抗体血清对吉利蒙念珠菌、热带念珠菌有抑制作用（P＜0.01）;假热带念珠菌抗体血清对热带念珠菌、假热带念珠菌有抑制作用（P＜0.01）.结论 小鼠念珠菌免疫抗体血清对念珠菌的生长有一定的抑制作用.     

The cross‐pin retained implant supported restoration: a study of gasket placement and leakage

Background: Advantages of cross‐pin retained implant supported restorations (ISRs) include predictable retrieval and predictable retention. Unlike direct to fixture (DTF) or cement retained restorations, the prosthetic design of a cross‐pinned restoration retains gaps at the interfaces between the crown, abutment and cross‐pin screw. These spaces permit leakage into the suprastructure and gasket placement has been recommended to prevent this leakage. Methods: Five different gaskets were assessed for their ability to prevent leakage into a cross‐pinned ISR. The gaskets tested were: cement admixture on the cross‐pin screw; cement admixture on the inner surface of the coping and the cross‐pin screw; cement admixture on the inner surface of the coping only; cement admixture placed 1 mm from the margin of the coping and a filler placed in the abutment chimney. Results: Only gaskets which sealed both the cross‐pin screw interface and the abutment‐crown interface prevented leakage. A filler placed in the abutment chimney prevented leakage into this space but did not prevent fluid accumulating between the coping and abutment. Conservative placement of cement at the margin of the coping failed to prevent leakage. Conclusions: Cement gaskets may effectively prevent leakage into a cross‐pinned ISR. However, the use of a cement as a gasket has to be weighed against the issue of predictable retrieval, cement extrusion and incomplete seating.     

Induced cross-protection responses against Cr(III) and Fe(III) ions in Saccharomyces cerevisiae

Stress tolerance of yeast Saccharomyces cerevisiae was examined after exposure to iron and chromium, which are essential minerals in low concentrations but can be toxic if present in high concentrations. Induction of possible cross-protection responses was performed with the yeast pre-treatment at the start of cultivation with low concentrations of Fe(III) or Cr(III) ions, which slightly inhibit the growth and the subsequent exposure to sub-lethal concentrations of Fe(III) or Cr(III) ions in the mid-exponential phase. No cross-protection was found if yeasts were pre-treated with 0.1 mM Cr(III) and subsequent exposure to 2.5 mM Fe(III) ions took place. If pre-treated with 0.1 mM Fe(III) Saccharomyces cerevisiae conferred protection to subsequent challenges with a sub-lethal concentration of 2.5 mM Cr(III) ions resulting in higher biomass formation and higher relative cell viability in comparison to cells without pre-treatment. It is shown for the first time that iron pre-treatment enhanced yeast condition against chromium related stress via cross-protection mechanism.     

Mature DC from skin and skin-draining LN retain the ability to acquire and efficiently present targeted antigen

Skin-draining LN contain several phenotypically distinguishable DC populations, which may be immature or mature. Mature DC are generally considered to have lost the capacity to acquire and present newly encountered Ag. Using antibody-opsonized liposomes as Ag carriers, we show that mature DC purified from skin explants are able to efficiently capture liposomes, process Ag encapsulated within them and activate Ag-specific CD4(+) T cells. Explant DC from mice with Langerhans cells (LC) expressing the primate diphtheria toxin receptor that were exposed to diphtheria toxin in vivo presented Ag as well as explant DC from wild-type mice, indicating that LC are not required and dermal DC are probably responsible for this presentation. We further show that all DC subtypes from LN that capture opsonized Ag are capable of cross-presenting it to CD8(+) T cells. Induction of additional maturation in vivo by LPS or treatment with double-stranded RNA did not alter the Ag presentation capacity of the skin or LN DC subtypes. These results suggest that mature DC present in skin-draining LN may play an important role in the induction of primary and/or secondary immune responses against Ag delivered to the LN that they take up by receptor-mediated endocytosis.     

Both Langerhans cells and interstitial DC cross-present melanoma antigens and efficiently activate antigen-specific CTL

Dendritic cells (DC) have a unique capacity to present external antigens to CD8(+) T cells, i.e. cross-presentation. However, it is not fully established whether the ability to cross-presentation is restricted to a unique subset of DC in humans. Here, we show that two major myeloid DC subsets, i.e. Langerhans cells (LC) and interstitial DC (Int-DC), have the ability to cross-present antigens to CD8(+) T cells in vitro. LC and Int-DC were obtained from DC generated by culturing human CD34(+)-hematopoietic progenitor cells with GM-CSF, FLT3-L, and TNF-alpha (CD34-DC). Both DC subsets were able to capture necrotic/apoptotic allogeneic melanoma cells and present antigens to CD8(+) T cells, resulting in efficient priming of naive CD8(+) T cells into CTL capable of killing melanoma cells. Strikingly, a single stimulation with either subset (LC or Int-DC) or total CD34-DC loaded with necrotic/apoptotic melanoma cells was sufficient to activate melanoma-specific memory CD8(+) T cells obtained from patients with metastatic melanoma to become effective CTL. Thus, this study provides the rationale to use CD34-DC loaded with necrotic/apoptotic allogeneic melanoma cells in a clinical trial.     

国内部分医院β-内酰胺类抗生素皮肤试验现状调查分析

摘 要 目的：采用问卷调查了解并分析我国医院β-内酰胺类抗生素皮肤试验的实际操作情况。方法：通过电子邮件或传真方式对国内100家医院的临床药师进行问卷调查。问卷内容涵盖医院的名称、级别;β-内酰胺类药物皮肤试验方法,包括皮试液的来源和浓度、操作方法、观察时间、阳性结果的判定标准;涉及过敏史时,β-内酰胺类药物的皮肤试验以及针对口服青霉素制剂是否需要皮肤试验等14个方面的相关问题。结果：共收到信息完整的反馈问卷80份（反馈比80%）。调查显示各医院β-内酰胺类药物皮肤试验流程各有不同。不同医院在抗生素皮试品种、皮试方法、涉及过敏史时药物的选择以及口服青霉素制剂是否进行皮试等方面均存在明显差异。结论：本研究反映了现阶段我国医疗机构在β-内酰胺类抗生素皮肤试验方面缺乏统一标准,亟需尽快出台相关临床指南或共识,以保证临床使用该类药物的安全性与规范性。     

高浓缩钚材料贯穿辐射场计算方法研究

目的 为满足高浓缩钚材料操作人员辐射安全评价和核安全审评的要求,需要对高浓缩钚材料周围形成的贯穿辐射场进行计算分析,解决高浓缩钚材料发射的γ射线和中子射线贯穿机理和强度的计算问题。方法 本文在对高浓缩钚材料的组成及所含放射性核素的辐射特性进行深入分析的基础上,基于γ射线宽束减弱规律和中子分出截面理论,研究提出了适用于高浓缩钚材料γ剂量率和中子剂量率计算模式。结果 贴近高浓缩钚材料表面γ剂量率和中子通量理论计算值与实际测量值同一量级,表明计算模型是正确的。距离钚材料表面0、30、100 cm处γ剂量率实际测量值均大于计算值,并且距离越远相对误差越大;中子模拟计算值与实际测量值相对误差随距离的增加而减小。结论 通过原理分析和实测验证,证明本文提出的高浓缩钚材料辐射场计算方法是合理可行的,能够满足科学性和准确性要求。