Objective:To investigate the related factors that affect the timing and prognosis of early tracheostomy in patients with multiple rib fractures.Methods:A retrospective case series study was conducted on medical data of 222 patients with multiple rib fractures who underwent tracheostomy in Affiliated Hospital of Yangzhou University from February 2013 to October 2019，including 160 males and 66 females，with the age of 18 to 85 years ［（49.5 ± 16.3）years］. According to the practice management guidelines for tracheostomy timing and the use of propensity score matching technology，there were 118 patients with tracheostomy within 7 days of tracheal intubation （early group） and 104 patients with tracheostomy after 7 days of tracheal intubation （late group） before matching，and there were 87 patients in early group and 87 patients in late group after matching. Data were compared between groups including the gender，age，underlying disease，injury severity score （ISS），Glasgow coma score （GCS），number of fractured ribs，total number of rib fractures （NTRF），first rib fracture，flail chest，traumatic brain injury，combined injuries （spine，maxillofacial，sternum），acute respiratory distress syndrome （ARDS），volume fraction of pulmonary contusion（VPC），blood lactic acid （within 24 hours of admission），hemothorax，pneumothorax，mechanical ventilation time，duration of tracheostomy，time from tracheal intubation to incision，length of hospital stay，length of stay in ICU，closed thoracic drainage，number of fiberoptic bronchoscopy，multi-drug resistant bacteria infection，ventilator-associated pneumonia，antibiotic use time，duration of sedative and analgesic drugs used and 28-day mortality. The multivariate Logistic regression analysis was used to predict independent risk factors for early tracheostomy. The Pearson method was used to compare the relationship between multiple factors. The receiver operating characteristic （ROC） curve was used to predict indicators that affect the prognosis of patients with early tracheostomy，and calculate the best cut-off value. The Kaplan-Meier single factor and COX multivariate survival were used to analyze the relevant factors affecting the 28-day mortality of patients.Results:（1） In early group，the NTRF，ARDS and VPC were higher than those in late group，and the time from tracheal intubation to incision and 28-day mortality rate were lower than those in late group （ P < 0.05），while the two groups showed no significant differences in the gender，age，underlying diseases and ISS （ P > 0.05）. （2） The multivariate Logistic regression analysis showed that there was statistical significance in NTRF （ OR = 1.775，95% CI 1.439-2.188），ARDS（ OR = 3.740，95% CI 1.441-9.711），VPC （ OR = 1.087，95% CI 1.052-1.124） （ P < 0.05）； the Pearson method analysis showed a significant correlation between VPC and NTRF （ r = 0.369， P < 0.05） and a low degree of correlation between ARDS and VPC （ r = 0.179， P < 0.05），but there was no significant correlation between ARDS and NTRF （ r = 0.132， P > 0.05）. （3） The ROC curve analysis showed that the area under the curve （AUC） of the VPC and NTRF ［AUC = 0.832 （95% CI 0.770-0.893），AUC = 0.804 （95% CI 0.740-0.868）］ were significantly higher than those of the number of rib fractures ［AUC = 0.437（95% CI 0.352-0.523），GCS ［AUC = 0.519 （95% CI 0.432-0.605）］ and ISS ［AUC = 0.484 （95% CI 0.398-0.571）］ （ P < 0.05）. After calculating the Yorden index，the best cut-off value for VPC was 23.9，and the best cut-off value for NTRF was 8.5. （4） The Kaplan-Meier single factor and multivariate COX model survival analysis showed that the 28-day survival ratio of patients with early tracheostomy was significantly better than that of late tracheostomy （ P < 0.05）. Conclusions:The NTRF，ADRS and VPC are independent risk factors for the timing and prognosis of early tracheostomy. There is a significant correlation between VPC and NTRF. The VPC ≥ 23.9% and or NTRF ≥ 8.5 can be used to predict early tracheostomy in patients with multiple rib fractures. Early tracheostomy may benefit the 28-day survival of patients with multiple rib fractures.

为明确16.5％吡嘧·丙草胺大粒剂对移栽水稻田的一年生杂草稗草、千金子、矮慈姑和异型莎草的防效及对水稻的安全性,进行了田间药效试验.结果表明,水稻移栽7d后撒施16.5％吡嘧·丙草胺大粒剂200～300 g/667m2,可以有效防除上述杂草.药后45 d该药剂4个不同用量处理对总草的株防效和鲜质量防效分别为89.48％～98.12％和89.96％～98.65％,均显著高于两个单剂处理,而且对水稻生长安全,不影响水稻产量.

植物受病原物诱导启动子是一类能对病原物的侵染作出响应的启动子,其活性主要局限于被侵染之时及被侵染的位点.植物受病原物诱导启动子的这一特性赋予其在抗病基因工程中潜在的应用价值.相比植物庞大的启动子组,已发现的植物受病原物诱导启动子仍是少数,关于其作用机制的研究仍有待加强和深入,而其调控的基因与植物抗病性关系还需要引起足够的重视.作者在对植物受病原物诱导启动子进行归类的基础上,重点关注了病原物诱导启动子调控基因的编码产物与植物抗病性的关系,对植物受病原物诱导启动子的顺式调控元件作了简要分析,并对该领域的发展动向进行了讨论.