were graded based on the Oxford Centre of Evidence-Based Medicine's Levels of Evidence (8).Five of

Background and ObjectiveInterstitial lung disease with lung cancer (ILD-LC) is rare and its management has not been fully described. This study aimed to investigate the management and prognosis of ILD-LC patients in China.MethodsThe present analysis is a retrospective real-world cohort study. Clinical data of ILD-LC patients were obtained from 3 hospitals in China. The overall survival (OS) of patients was analyzed. Univariate and multivariate regression analyses were performed.ResultsOne hundred eighty-four ILD-LC patients included were biased toward male (85.3%), smokers (75.5%), idiopathic pulmonary fibrosis (IPF) (58.2%) patients with comorbidities (67.9%) and ECOG-PS score of 1 (65.2%). Most patients were advanced peripheral non-small cell lung cancer. The initial anti-cancer regimen for ILD-LC is mainly chemotherapy, and patients with early-stage LC prefer surgery. In the anti-cancer cohort, the number of ILD-LC patients who underwent the 2nd and 3rd or more anti-cancer regimens were 78 (55.7%) and 32 (22.8%), respectively. In the non-anticancer cohort, the median OS was 3.5 months. In the early-stage cohort, the median OS was 14.2 months in the systematic therapy group; however, the median OS was not reached in the surgery group. In the advanced-stage cohort with systematic therapy, the median OS was 7.2 months. Interstitial pneumonia (IIP) and anti-angiogenesis were associated with OS in the univariate analysis, whereas anti-angiogenesis was an independent protective factor for advanced LC with ILD.ConclusionPatients with ILD-LC have very poor prognosis. Appropriate anti-tumor treatment can prolong the survival time of patients who can tolerate it. Targeted therapy and immunotherapy are alternative treatments for LC patients with mild ILD. For ILD patients with advanced LC, antiangiogenic regimens significantly improve the prognosis of the disease.

目的 探讨中国北方汉族人群维生素D受体(VDR)基因单核苷酸多态性与慢性阻塞性肺疾病(COPD)并发骨质疏松的关系.方法 回顾2007年9月-2017年10月收治的COPD急性加重住院患者379例资料,分为非骨质疏松组155例与骨质疏松组224例,提取全血样本的基因组DNA.利用UCSC基因组浏览器和Haploview 4.2软件确定VDR基因的标签单核苷酸多态性(tagSNP).应用Sequenom MassARRAY SNP检测技术对VDR基因的tagSNP进行基因型分析.采用Logistic回归方法研究其共显性、显性、隐性等遗传模式下各SNP的比数比(OR值)和置信区间(CI),评估VDR基因单核苷酸多态性与COPD并发骨质疏松的关系.结果 两组在性别、年龄、是否饮酒、外周血血小板计数、血磷、血肌酐等参数上差异均有统计学意义(P<0.05).在筛选出的VDR基因17个tagSNPs(rs2238140 G/A,rs2228570 G/A,rs2408877 A/T,rs12721370 C/A,rs7299460 T/C,rs2239184 G/A,rs2239186 A/G,rs7136534 C/T,rs12721364 G/A,rs2853561 C/T,rs7965943 T/G,rs11168287 G/A,rs11608702 T/A,rs2239179 T/C,rs2189480 T/G,rs59707231 T/A,rs2853559 C/T)中,rs2853561携带T/C和T/T基因型的COPD患者,发生骨质疏松的风险较C/C更低(在显性遗传模式下,T/C+T/Tvs.C/C,OR=0.34,95％CI 0.18～0.63,P=0.0003539),差异有统计学意义.结论VDR基因中的rs2853561与COPD并发骨质疏松之间存在相关性.VDR基因单核苷酸多态性在COPD并发骨质疏松发病机制中的具体作用有待进一步研究.

Objective: To explore a simple method for early detection of osteoporosis in patients with chronic obstructive pulmonary disease (COPD), by analyzing the correlation between computed tomography (CT) values of the thoracolumbar vertebrae and dual energy X ray absorptiometry (DXA). Methods: 86 patients with acute exacerbation of COPD were included in this study. The average age of the patients, including 57 males and 29 females, was 74±10 years. They all received chest CT and DXA examination within 1 month after admission. The relation between each CT value from 6(th) thoracic vertebrae (T6) to 1(st) lumbar (L1) and T-score measured by DXA was analyzed by linear correlation analysis with SPSS 17.0 software. Results: The mean CT value of T6-L1 was significantly lower in patients with osteoporosis than that in patients with normal bone mineral density (P<0.05). The CT values of T6-L1 were positively correlated with T-score (P<0.001). The ROC curve analysis of T6-L1 CT value showed that the area under ROC curve of L1 CT value was the largest, and therefore the accuracy of diagnosis of osteoporosis by L1 CT value was better.A L1 CT value lower than 100 HU was proposed as the threshold for lower bone mass or osteoporosis in the patients. Conclusion: It is possible to detect osteoporosis in patients with COPD through evaluating the CT values of T6-L1. This method could potentially reduce X-ray irradiation and expense. Early detection and intervention in patients with COPD and osteoporosis could improve the prognosis of patients.

[目的]探讨miR-145在配对的非小细胞肺癌(non-small cell lung cancer,NSCLC)患者肿瘤组织和癌旁组织中的表达情况,分析其与临床病理因素和预后的关系.[方法]应用实时定量聚合酶链反应(q-RT-PCR)检测miR-145在配对的NSCLC患者肿瘤组织和癌旁组织中的表达水平.[结果] miR-145在NSCLC患者肿瘤组织中的表达水平明显低于癌旁组织(P＜0.001).miR-145诊断NSCLC的ROC曲线下面积为0.895.miR-145在Ⅲ～Ⅳ期和中低分化的NSCLC患者肿瘤组织中的表达水平明显低于Ⅰ～Ⅱ期和高分化的肿瘤组织(P＜0.05).miR-145低表达组的总生存率明显低于miR-145高表达组(P＜0.05).[结论]miR-145在NSCLC组织中的表达下调,在NSCLC的发生中可能发挥抑癌基因的作用,可能是NSCLC的诊断及预后标志物之一.

Objective To detect respiratory viruses and atypical pathogens by rapid methods, and to investi-gate the current status of viruses and atypical pathogens associated infection in hospitalized patients with community-acquired pneumonia. Methods 301 community acquired pneumonia patients were treated in department of respirato-ry diseases of the 306th hospital of PLA from February 2013 to February 2015, and their influenza virus A and B (FluA, B), respiratory syncytial virus (RSV), adenovirus (ADV) and eosinophilic lung legionella antigen (LP) were detected by colloidal gold immune chromatography ( GICA) , and rapid culture method was used to detect pres-ence of mycoplasma pneumoniae ( MP) infection. The detection rate of patients were analyzed to identify the common rules and characteristics. Results The total positive detection rate of those respiratory viruses and atypical pathogens&nbsp;was 55. 5%. Elderly patients (≥65 years old) had higher Flu A/B detection rate comparing with patients younger than 65 years old (P<0. 05), but elderly patients (≥65 years old) had lower detection rate of MP and LP compa-ring with patients below 65 years old (P<0. 05). The positive detection rate of FluA in winter and spring was signifi-cantly higher than that in summer and autumn ( P<0. 05 ) . The positive detection rate of MP in winter was signifi-cantly higher than that in summer and autumn (P<0. 05). The detection rate of FluA antigen in patients without un-derlying diseases was lower than that in patients with underlying diseases (P<0. 05). Conclusion The respiratory viruses and atypical pathogens are the important pathogens in hospitalized patients with community-acquired pneumo-nia. The important factors of the risk of infection are season, age, and a merger of underlying diseases.

Objective To investigate the influence of chronic alcohol ingestion on the severity of acute lung inj ury induced by oleic acid and lipopolysaccharide in rats,and the expression of surfactant-associated protein A(SP-A) in the lung.Methods 32 male Sprague-Dawley rats were divided into four groups,eight rats in each group.The rats in alcohol group received 20% Chinese alcohol as their drinking water for six weeks.Then the rats of lung injury groups received intravenous injection of 0.15 ml/kg oleic acid at first and celiac inj ection of 4 mg/kg lipopolysaccharide two hours later.The expression of SP-A in the lung was measured by Western blot.Results Compared with the saline group,the protein content in bronchoalveolar lavage fluid increased in alcohol-inj ury group and water-inj ury group,the change was more deteriorated in alcohol-inj ury group.And the expression of SP-A protein in the lung decreased after having been inj ured,especially in alcohol-inj ury group.Conclusions Chronic alcohol ingestion has no significant effect on lung structure and the expression of SP-A protein in lung tissue of rats in our study.But the severity of the lung inj ury and the decrease of SP-A expression in lung are deteriorated when acute lung inj ury happens.

Objective To investigate the effect of simulated microgravity on the tissue structure and the mRNA and pro-tein expression of HSP70 in lungs of rhesus macaques .Methods Fifteen healthy young male rhesus monkeys were randomly divided into 3 groups:control group (group A, n=5), 6 weeks′simulated microgravity group (group B, n=5) and recovery for 4 weeks after 6 weeks of simulated microgravity group (group C, n=5).-10 degree head-down-tilt was used to simulate microgravity .HE staining and transmission electron microscopy were used to observe the histopathological and ultrastructural changes in pulmonary tissues .The expression and location of HSP 70 in lung tissues were observed by immunohistochemistry (IHC) method.The mRNA and protein expression of HSP70 in lung tissues were detected by quan-titative real-time PCR ( Q-PCR) and Western blotting .Results Compared with group A , histopathological examination re-vealed alveolar septal thickening , partial fusion of pulmonary alveoli and alveolar and interstitial lymphocytic infiltration in groups B and C .Ultrastructure examination showed smaller and irregular nuclei of alveolar epithelial cells , an increased number and volume of the lamellar bodies , enhanced evacuation , part of vacuolar degeneration and mitochondrial swelling in groups B and C .IHC results showed that HSP 70 was expressed in bronchial epithelial cells , vascular endothelial cells and alveolar epithelial cells of pulmonary tissues in each group , either in cytoplasm or in nucleus .In addition , the alveolar interstitial and alveolar exudates in groups B and C also showed positive signals .Q-PCR and Western blotting results showed that HSP70 was expressed in all of the three groups , but no significant difference was found between any two groups (P>0.05).Conclusion Medium or long-term simulated microgravity can cause damage to the lung tissue of rhesus mon-keys, but it has no effect on the expression of HSP 70 in the lung tissue.

Objective To investigate the effect of simulated microgravity on growth , morphology, protein expression and virulence gene expression of Klebsiella pneumoniae (KPN).Methods KPN was divided into simulated microgravity group and control group in the experiment .The former group was in the ambient of simulated microgravity in a clinostat .The bacterial growth curves , morphologyical changes in electron microscopy , and protein expression were detected by SELDI-TOF-MS, and the expression of 4 virulence genes(ureA,wabG,uge and fimH) by real-time fluorescence quantitative PCR (RT-PCR) in both groups.Results Compared with the control group , the growth of KPN under simulated microgravity was accelerated , and the total bacterial count increased in microgravity group .The bacterial morphology in microgravity group was changed under scanning electron microscopy (SEM), and thinner and longer bacteria were increased .The transmission electron microscopy ( TEM) analysis revealed increase in cytoplasmic granular substance in microgravity group .Proteome analysis showed that the expression of 18 proteins was changed , half of which up-regulated and the rest were down-regula-ted.Those 18 proteins were searched in the protein library .And 21 proteins of a similar molecular mass were retrieved ,13 of which,proteins with known functions ,were closely related to bacterial life activities .RT-PCR results showed that four virulence genes of KPN were down-regulated.Conclusion Upon exposure to simulated microgravity , the growth and repro-duction of KPN are accelerated and enhanced .The bacterial morphology is changed .The strain′s protein expression and four virulence genes expressionare also changed .Therefore,microgravity can change the characteristics of KPN .

Objective To investigate the effects of simulated microgravity on JNK/c-Jun/c -Fos cell signaling pathway change in lung of rhesus monkey.Method s Fifteen healthy young male rhesus monkeys were randomly divided into 3 groups:control group (group A, n=5), 6 weeks′simulated weightlessness group (group B, n=5) and recovery for 4 weeks after 6 weeks of simulated weightlessness group ( group C, n=5).-10 degree head-down-tilt was used to simulated weightlessness.HE staining was used to observe the histopathological changes of the lung tissues.Western blot assay was performed to detect the levels of JNK , c-Jun, c-Fos and their phosphorylated levels.Results Com-pared with group A , histopathological examination revealed alveolar septal thickening , partial fusion of pulmonary alveoli and alveolar and interstitial lymphocytic infiltration in group B and C.And the pathological changes in group C were lighter than those in group B.The increased levels of JNK , c-Fos, p-c-Fos and p-c-Jun protein were observed in group B and C by western blotting.Conclusions Simulated microgravity can cause lung tissue damage and increase the levels of JNK, c-Fos, p-c-Fos and p-c-Jun protein in lung tissue of rhesus monkey.Microgravity may promote downstream genes expression by JNK/c-Jun/c-Fos cell signaling pathway which may be related to the damage of lung tissue in simulated microgravity.

病例资料 男,25岁. 既往体健. 此次主因咳嗽伴发热4月余入院. 患者于2015~5月无诱因出现咳嗽,无明显咯痰,间断伴有发热,体温最高达37. 5℃,稍有胸闷,无胸痛,咯血,无腹泻、腹痛,无尿频、尿急症状,体重下降2 公斤. 期间7 月就诊,查胸部CT""右肺上叶前段见软组织肿块影,纵隔淋巴结肿大,考虑诊断"右上肺癌伴纵隔淋巴结肿大",给,予对症抗感染,增强免疫力等治疗,于7 月30 日转院至"中国医学科学院肿瘤医院",8 月行肺部增强CT,"仍可见右上肺较大不规则肿块影,密度不均,最大中心层面大小约7. 2 × 7. 6CM,纵隔淋巴结肿大,右侧少量胸腔积液"(见图1),仍考虑"恶性肿瘤可能性大",遂行经CT引导下经皮肺穿,病理诊断"肺组织急慢性炎,坏死,大量嗜酸性细胞浸润及散在钙化,并见霉菌样结构,考虑霉菌感染可能性大",未予特殊治疗.

Objective:To develop a set of pharmaceutical purified water supply system with lower cost, higher degree of reliability, easier maintenance, multi-functions. Methods: A centralized primary purified water system established as to produce the soften water, which be delivered to each water point and to the pretreatment of purifying process. Then the purification will be preceded according to different functions of different water points, through one-level or second-level reverse osmosis device. In order to ensure the un-interruptability and stability of source water supply and soften water supply, a double pump frequency device will be equipped. Results:After three-year clinical application, it indicated that the centralized pharmaceutical purified water supply system would be a system with stable performance, low cost, and easy to maintain and operate. Conclusion:The design of the pharmaceutical purified water supply system satisfies the requirements of Clinical Medicine.

Objective To observe the effect of N-acetylcysteine (NAC) on pulmonary injury under simulated weightlessness in rats. Methods Tail-suspension method was used to establish the models of weightless simulation in rats. A total of 24 clean Wistar rats were randomly divided into group A, B and C ( n=8 for each group) . Group B was treated with NAC (300 mg/kg) by intragastric administration every day from the first day, while group A and C were treated with same volume of sterile water via intragastric injection. The models of weightless simulation were established in group A and B by tail-suspension method after the rats had been administrated for 2 d, while the rats in group C were free-running in the cage. The rats were killed at the end of the 7th d. The levels of superficial CD11b/c of neutrophilic granu-locyte, reactive oxygen species (ROS) concentration of neutrophilic granulocyte, contents of IL (interleukin)-10, IL-6 and TNF ( tumor necrosis factor)-αin the blood samples were detected. The superior lobe tissues of right lung were given hematoxylin and eosin stain ( HE stain) , and the pathological changes of lung tissues in slices were observed. Results In group A, under microscope, the sizes of alveoli were discrepant, the alveolar septum became wide with edema, and blood vessels were dilated and congested, and neutrophils and infiltrated lymphocytes were found in the interstitial. Simi-lar changes of group A were found in group B, but the degrees were less than those in group A, while there were no obvi-ously similar changes in group C. There were statistically significant differences in CD11b/c, ROS concentration, TNF-α, IL-10 and IL-6 (P<0. 05, P<0. 01). Conclusion NAC can alleviate inflammation and lung damages of rats under simulated weightlessness, and the antioxidation effect of NAC may play a role in protection of lung injury under weightless condition.

OBJECTIVE To determine the distribution and drug resistance characteristics of pathogens in patients with central venous catheter‐related bloodstream infections (CRBSI) and guide clinical doctors to select antibiotics correctly .METHODS A total of 2344 patients with indwelling catheters during Jun .2010 to Jun .2013 were included and retrospectively analyzed .The venous blood and catheter tip of the 218 patients were cultured with a quantitative method and their antibiotic susceptibility was detected . Data were analyzed with the statistical software SPSS 16 .0 .RESULTS A total of 218 patients were confirmed with CRBSI ,with infections rate of 9 .3% . Totally 218 strains of pathogens were isolated ,including gram‐positive bacteria (64 .7% ) ,gram‐negative bacilli (21 .1% ) and fungi (14 .2% ) .Pathogens ranking the first four were Staphylococcus epidermidis (28 .9% ) , Staphylococcus aureus (14 .2% ) , Enterococcus (8 .3% ) and Candida albicans (8 .3% ) .Gram‐positive bacteria were severely resistant ,but susceptible to linezolid ,vancomycin and teicoplanin .Gram‐negative bacteria had high resistance to various antibacterials , but less resistant to cefoperazone/sulbactam , piperacillin/tazobactam and imipenem .Candida albicans and C .tropicalis were susceptible to fluconazole and voriconazole .C .glabrata was resistant to fluconazole but susceptible to voriconazole .CONCLUSION Gram‐positive and gram‐negative bacteria are still the most important pathogens in CRBSI and have multiple drug‐resistances , which are difficult for treatment .Bacterial culture and antibiotic susceptibility tests are very important to select antibiotics correctly for treatment of CRBSI .

Objective To investigate the effect of Atorvastatin on pulmonary infection induced by Streptococcus pneumonia in rats under simulated weightless condition, and to provide the theoretical basis for protection of respiratory system and infection therapy for astronauts. Methods A total of 40 Wistar rats were randomly divided into weightless-ness + infection group ( WI group, n =10 ) , weightlessness + infection + statin group ( WIS group, n =10 ) , control + infection group (CI group, n=10) and control + infection + statin group (CIS group, n=10). The models of simulated weightlessness were established in WI and WIS groups, while the rats in CI and CIS groups were fed in mouse cages with free running space. Bacterial pneumonia models were established in the 4 groups after the rats had been fed for 3 d. WIS and CIS groups were treated with Atorvastatin 10 mg/( kg·d) via intragastric administration on the first experiment day, while WI and CI groups were treated with same volume of sterile water via intragastric injection. The rats were killed at the end of tail-suspension for 8 d. The routine blood test and level of CD11b/c of neutrophilic granulocyte in the blood samples were detected, and the pathological changes of lung tissues in slices were observed. Results In the four groups, local congestion and spot-film hemorrhage in different degrees were found in the surfaces of lung tissues by macroscopic observation;inflammatory cells were infiltrated in the interstitial alveolar space which was mainly a large num-ber of neutrophils under the microscope, and some parts of constructions in the alveolar space disappeared. All of the above pathological changes showed that WI group was the severest, and CIS group was the least, and the changes were more prom-inent in superior lobe of rats under simulated weightlessness. There were significant differences in white blood cells and neutrophilic granulocyte counts in the four groups (F=3. 67, P<0. 05; F=7. 47, P<0. 01), and the values were the highest in WI group and the lowest in CIS group. There were significant differences in CD11b/c value in the four groups (P<0.01),andthevaluewasthehighestinWIgroup(167.75±28.39)andthelowestinCISgroup(115.57±18.57). No significant differences were found in NEU percentage (NEU%) in the four groups (P>0. 05). Conclusion Pulmona-ry infection induced by Streptococcus pneumonia in rats under simulated weight condition, is more serious in inflammatory reaction and pathological lesions, while Atorvastatin may have protective effects on lung tissues under weight condition.

Objective A prospective observational study to investigate the distribution and antimicrobial resistance of pathogenic bacteria in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in Beijing, China. Methods Patients with AECOPD were recruited from 11 general hospitals. Sputum specimens were cultured and bacteria identified. Antibiotic susceptibility was determined for each isolate, and presence of antibiotic resistance genes was evaluated using polymerase chain reaction. Results Pathogenic bacteria were isolated from 109/318 patients (34.28%); 124 isolates of 22 pathogenic bacterial species were identified, including Klebsiella pneumoniae (16.94%), Pseudomonas aeruginosa (16.94%), Acinetobacter baumannii (11.29%), Streptococcus pneumoniae (8.87%), and Staphylococcus aureus (7.26%). S. aureus was sensitive to tigecycline, teicoplanin, vancomycin and linezolid but resistant to penicillin and levofloxacin. K.pneumoniae, P. aeruginosa, A. baumannii and E. coli were susceptible to amikacin and cefoperazone. Conclusions K. pneumoniae and P. aeruginosa are the most common pathogenic bacteria in AECOPD cases in Beijing, China. Our antibiotic resistance findings may be helpful in selecting antibiotic therapy.

Objective To explore the protective effect of N-acetylcysteine ( NAC) for pneumonia caused by infection of streptococcus pneumoniae in rats. Methods This study used internationally accepted method of produ-cing animal model that infected by streptococcus pneumoniae. 24 healthy clean male Wistar rats were randomly divid-ed into 3 groups:the group A ( infection and no NAC group ) , the group B ( NAC and infection group) , the group C (no infection and no NAC group). NAC (300 mg/(kg·d)) were fed by intragastric administration on the first day, while the same amount of distilled water was fed in the control group. The rats were intratracheally instilled with 0. 4ml suspension of streptococcus pneumoniae on the fourth day. At the same time, the no-infection groups were intra-tracheally instilled with 0. 4 ml sterile saline. At the end of experiment, the rats were killed. The leukocytes and neu-trophils, CD11b and DCFH-DA in the blood were analyzed. Results In the group A, alveolus showed different si-zes, alveolar septum became wide and thick, and large number of neutrophils and lymphocytes infiltrated in the inter-stitial. Some changes like these could be find in the group B, but less severe than the group A. A few of the same changes but less severe could be observed in the group C. Compared with the group A and the group B, there was a statistically significant difference in the mean value of CD11b/c (F=53. 65, P<0. 01). The same trend was ob-served in ROS (F=63. 97, P<0. 01), IL-10 (F=74. 66, P<0. 01) and IL-6 (F=238. 59, P<0. 01). The a-bove indicators were lower in the group B than in the group A. Conclusion NAC could alleviate inflammatory re-sponse these changes. The antioxidation effect of NAC may play a role in protection of lung infection. N-acetylcys-teine can reduce inflammation and lung tissue damage of rats by infection of pneumococcal pneumonia. Its antioxidant effect may have a protective effect in pneumonia caused by Streptococcus pneumoniae.

ObjectiveTo determine the clinical correlation between acute physiology and chronic health evaluationⅡ (APACHEⅡ) score in COPD patients with hypercapnic respiratory failure and invasive positive pressure ventilation (IPPV).Methods 64 cases of AECOPD with severe typeⅡ respiratory failure receiving the treatment of mechanical ventilation in RICU in the 306th hospital of PLA from January 2008 to June 2012 were retrospectively studied. The parameters of mechanical ventilation was analyzed by ttest; relationship between the predicted mortality of APACHEⅡ and actual mortality was analyzed by the Spearman correlation test, the application value of predicted mortality rate was evaluated by ROC curve.ResultsThe mean age of enrolled patients was (75.69±7.98) years, the minimum age was 54 years, the maximum age was 91 years. The total duration of mechanical ventilation ranged from 3 to 226 days, the median duration of MV was 13(7,25) days. Finally, 35 cases successfully ventilator-weaned, weaning success rate was 54.7%; 14 cases of weaning failed; 15 patients died, the mortality rate was 23.4%. 22 patients ventilated for more than 21 days, which accounted for 34.4%; 6&nbsp;patients received repeated mechanical ventilation therapy. The mortality rate was higher with the increase of APACHEⅡ score, Spearman correlation analysis showed that the correlation coefficient rp=0.941(P=0.005), the predicted mortality of APACHEⅡ was higher than the actual mortality. The area under the ROC curve of APACHEⅡ(Az) was 0.642 (P=0.050, 95%CI: 0.503-0.781); when the APACHEⅡ score reached 28.5, the Youden index was the highest (0.398), so when the APACHEⅡ score was above 28 points, the mortality rate increased significantly.Conclusion Mechanical ventilation is an effective and reliable method to treat AECOPD accompanied with severe typeⅡ respiratory failure. APACHEⅡ score can be used to evaluate the severity of illness, but only has a limited value predicting the mortality for AECOPD patients with severe typeⅡ respiratory failure.