问题3：如何预防呼吸机相关肺炎？

解答：呼吸机相关肺炎是重症创伤伤员最主要的院内感染,不仅延长通气时间和住院时间,增加医疗成本,也是严重创伤的重要致死因素。预防呼吸机相关肺炎需从以下几个方面努力：（1）呼吸机和呼吸管路的管理,包括呼吸机的清洗消毒,呼吸管路的定期更换、湿化器的使用等;（2）做好排痰和吸痰,做好口腔护理和声门下吸引;（3）定时更换体位和物理治疗;（4）尽量缩短呼吸机治疗和气道开放的时间。     

问题4：颅脑创伤患者有哪些发生颅内感染的危险因素？

解答：颅内感染是颅脑创伤的严重并发症,延长患者的住院时间,增加致死致残率,显著影响预后。文献报道发生率7.9％。颅脑创伤患者发生颅内感染的主要危险因素有：（1）创伤的严重程度;（2）脑脊液漏：头皮、颅骨和脑膜的三重保护作用均已破坏,脑组织或脑室系统与外界环境的直接相通,为病原菌提供重要的感染途径;（3）外引流：引流管的存在导致颅内与外界环境相通,细菌可经头皮切口处逆行而上,引流液返流也可能成为重要的感染源和细菌培养基;（4）多次开颅手术。     

CAFs对乳腺癌细胞生物学特性的影响及机制探讨

目的：通过乳腺癌间质成纤维细胞（ carcinoma-associated fibroblasts,CAFs）与乳腺癌细胞系MDA-MB-231共培养的体外细胞实验及裸鼠接种的在体动物实验,观察CAFs对乳腺癌细胞增殖、凋亡、侵袭和转移活性的影响,并探讨其作用机制。方法：体外实验：分离培养浸润性导管癌组织中CAFs和正常成纤维细胞（ normal fibroblasts,NFs）,然后分别与乳腺癌细胞MDA-MB-231体外共培养,采用MTT法、流式细胞仪、Ma-trigel人工模拟基底膜法分别检测乳腺癌细胞的增殖、凋亡、细胞黏附和侵袭能力。动物在体实验：选择乳腺癌细胞系MDA-MB-231、CAFs和NFs,结合生理盐水（NS）、基质细胞衍生因子-1（SDF-1）及其配体拮抗剂AMD3100,组成不同的组别并接种于裸鼠（共6组）。观察肿瘤的大小,有无淋巴结、肺、肝脏转移。留取血标本及肿瘤组织行SDF-1表达水平的检测。结果：MDA-MB-231与CAFs和NFs共培养后乳腺癌细胞的增殖活性显著增强,其中CAFs的作用较NFs更强（P＝0.011）;CAFs组的黏附能力（34.70±4.84个/视野）明显强于NFs组（20.16±3.09个/视野）,P＝0.000;而CAFs组的侵袭性（89.0±4.62个/视野）也明显强于NFs组（81.6±6.08个/视野,P＝0.045）。CAFs组中的MDA-MB-231的早期凋亡率（2.9±2.4）较NFs组（5.0±4.2）明显降低（P＝0.026）;MDA231﹢CAFs ﹢NS 组的种植肿瘤平均体积最大（9.092±2.662cm3, P＝0.000）;此外,该组共有4只（66.6％）,MDA231﹢NS组有2只（33.3％）存在腋窝淋巴结转移,未见肝肺转移灶。在MDA231﹢CAFs﹢NS组中,血标本 SDF -1值（75.25±16.23pg/ml）、肿瘤组织标本中 SDF -1mRNA值（11.686±8.926）、组织中SDF-1蛋白表达水平（1.006±0.327）均为最高,与其他各组相比均有统计学差异（ P＝0.000）。结论：CAFs可影响乳腺癌肿瘤细胞的生物学特性,具有促进肿瘤细胞增殖,增强其黏附、侵袭及转移能力。其机制可能是通过乳腺癌间质成纤维细胞分泌SDF-1与其特定的受体CXCR4结合这一信号通路来实现的。     

Effect of penehyclidine hydrochloride on patients with acute lung injury and its mechanisms

Objective： To assess the effects of penehyclidine hydrochloride on patients with acute lung injury （ALI）, to observe the expression of Toll-like receptor 4 （TLR4） on the peripheral monocytes of ALI patients and changes of inflammatory ＆ anti-inflammatory cytokines and to investigate the mechanism of TLR4 in ALI.Methods： Forty-five patients with ALI were randomly divided into penehyclidine hydrochloride treatment group （P group, n=21） and conventional treatment group （control group, C group, n=24）. Patients in both groups received conventional treatment, including active treatment of the primary disease, respiratory support, nutritional support and fluid management therapy, while those in P group were given penehyclidine hydrochloride （1 mg, im, q. 12 h） in addition.The TLR4 expression of 20 healthy volunteers were detected.The clinical effect, average length of stay in ICU and hospital,values of PaO2 and PaO2/FiO2, expression of TLR4 on the surface of peripheral blood mononuclear cells and some serum cytokines were evaluated for 48 h.Results： The general conditions of the two groups were improved gradually and PaO2 increased progressively.Compared with 0 h, PaO2 and PaO2/FiO2 at 6, 12, 24 and 48 h after treatment were significantly increased （P＜0.05）. The improvement in P group was obviously greater than that in C group （P＜0.05）. The average length of hospitalization showed no difference between the two groups, but penehyclidine hydrochloride significantly decreased the average length of stay in ICU （t=3.485, P＜0.01）. The expression of TLR4 in two groups were both obviously higher than that of healthy volunteers （P＜0.01）. It decreased significantly at 24 h （t=2.032, P＜0.05） and 48 h （t=3.620, P＜0.01）and was lower in P group than in C group. The patients who showed a higher level of TLR4 expression in early stage had a worse prognosis and most of them developed acute respiratory distress syndrome （ARDS）. The incidence of ARDS was 23.8% in P group and 29.17% in C group at 24 h.Until148 h, there were other two patients developing ARDS in control group. Serum IL-l, IL-8 and TNF-α expressions reduced after 24 h in both groups. The reduction in P group was more obvious than that in C group （P＜0.05）. IL-13 increased gradually from 0 h to 24 h, and decreased slightly at 48 h, which showed no difference between two groups （t=1.028, P＞0.05）.Conclusions： Penehyclidine hydrochloride improves the arterial oxygen pressure, down-regulates the expression of TLR4 and restrains the inflammatory cytokines in the downstream of TLR4 signaling pathway. It prevents the development of ALI and can be considered as an important drug in ALI treatment.     

中毒事件应急医疗救援实践与思考

军队大型综合性医院除承担本地区部队和地方广大人民群众急慢性病和危重病的救治任务外,在突发公共卫生事件及灾害应急医疗救援中起到战略支撑作用。急性中毒事件威胁人民群众生命安全甚至导致群体伤亡,影响社会稳定。军队大型综合性医院在应对急性中毒事件中具有极其重要的作用,为挽救中毒患者的生命、降低死亡率与致残率,维护社会和谐稳定作出了很大贡献。虽然对于应对突发事件积累了很多成功经验,但在实际应急医疗救援中仍存在一些普遍但不可忽视的问题和不足。