Objective To analyze the causes of time consumption in CT enhancement scanning (CTES) and CT angiography (CTA) examinations in order to optimize the procedures, and help to save time and medical costs for patients. Methods A total of 2328 outpatients and 1402 inpatients to take CTES and CTA examinations were randomly selected as the normal control group, and another 2085 outpatients and 793 inpatients who underwent the optimized procedures were randomly selected as the experimental group. The problems of time consumption and patients'satisfaction degree were analyzed. Results The major causes for time consumption in CTES and CTA examinations included taking wrong contrast medicine, forgetting to take contrast medicine, having no auxiliary examination results, waiting in the wrong line, and opening the cap of contrast medicine. The time spent for checkup for inpatients and outpatients in the control and experimental groups was (119.8±15.6) minutes and (31.5±8.6 ) minutes vs (55.2 ± 10.6) minutes and (8.4 ±2.1) minutes. The satisfaction degree of inpatients and outpatients in the control and experimental groups were 90.16%(1264/1402) and 88.66%(2064/2328) vs 98.49%(781/793) and 97.94%(2042/2085). The experimental group spent shorter time and had higher satisfaction degree than those in the control group, and the differences were statistical significantly, tinpatient=34.96, P<0.01, toutpatient=12.03, P<0.01;χ2inpatient=55.20, P<0.01,χ2outpatient=146.27, P<0.01. Conclusions After the procedures of CTES and CTA examinations are optimized, the checkup time is significantly shortened, and patients' satisfaction degree is remarkably improved.

Objective To investigate the clinical value of acoustic radiation forcs impulse (ARFI)in quantitative evaluating placental elasticity.Methods The study population included 487 normal pregnant women,and ARFI generated shear wave velocity (SWV)was measured.On the basis of gestational ages, placental sites and sampling depths in region of interest (ROI),the normal population was divided into different groups.One-way analysis of variance was used to compare the discrepancy on the SWV values amomg the nomal placental sites or the sampling depths in ROI.Pearson correlation coefficient were used to assess the possible relationships between the normal placental SWV values and the different gestational ages or the placental grades.A total of 5 1 cases were diagnosed with severe preeclampsia,among them 25 cases were categorized as severe preeclampsia with fetal growth restriction (FGR).The placental SWV values were measured and compared with those of the normal population.The pathological examinations were performed on 50 normal and 5 1 abnormal placentas.Results Basing on the placental sites,the normal population were divided into three groups:anterior wall,lateral wall and posterior wall groups.Compared with the posterior wall group,the placental SWV values in the anterior wall or lateral wall group significantly decreased (P <0.05).No statistical significant difference was found between the anterior wall group and the lateral wall group.Basing on the distance from the sampling depths to the probe (range from 2 to 7.99 cm,and each additional 1 cm corresponding a group),the normal population were divided into six groups.There was statistical significant difference for the placental SWV values between the two groups of distance in the range of 2.0 to 5.99 cm and 6.0 to 7.99 cm (P <0.05).There was no statistical significant difference between the other two groups.The mean SWV value was (0.78±0.08 m/s)in the normal group. No significant relationships were found between the placental SWV values and the gestational ages of the normal population.However the placental SWV values were significantly related to the placental grades.For the placental SWV values,there was statistical significant difference between the normal group and the abnormal group (P <0.05).No statistical significant difference was found between the severe preeclampsia group and the severe preeclampsia with FGR group.The pathological examinations also showed significant changes in the abnormal group.Conclusions ARFI may quantitatively analyze the placental elasticity and make a difference between nomal and abnormal placenta.

Objective To investigate the efficacy and application of bronchoalveolar lavage in chil-dren with severe pneumonia undergoing mechanical ventilation. Methods Using a prospective randomized controlled clinical study, 202 children with severe pneumonia received mechanical ventilation in Hunan Children′s Hospital from January 2016 to January 2018 were selected as the subjects. According to the digital method,all cases were divided into treatment group (101 cases) and control group (101 cases) randomly. The patients in the control group were given conventional treatment ( anti-infection and symptomatic thera-py) . The treatment group was treated with bronchoalveolar lavage on the basis of conventional treatment. The basic situation,the respiratory function before and after the treatment,the inflammation index,the curative effect and the prognosis of two groups were analyzed. Results There were no significant differences between the two groups in gender,age,course pre-admission,pediatric critical illness score,respiratory function and in-flammation index ( P>0. 05 ) . The respiratory function indexes of the treatment group were obviously im-proved 2 hours after the treatment and the PaO2 ,PaO2/FiO2 and SaO2 were significantly higher than those of the control group[PaO2:(82. 4 ± 6. 4) mmHg(1 mmHg=0. 133 kPa) vs. (74. 0 ± 5. 5) mmHg, PaO2/FiO2:(360. 2 ± 21. 3) mmHg vs. (332. 6 ± 23. 5) mmHg,SaO2:(94. 9 ± 8. 2)％ vs. (88. 6 ± 10. 3)％], while the PaCO2 were significantly lower than the control group [ ( 37. 3 ± 10. 3 ) mmHg vs. ( 45. 8 ± 5. 5 ) mmHg],and the differences were statistically significant (P<0. 05). Five days after treatment,the WBC, PCT and CRP of treatment group were significantly lower than those in the control group[WBC:(8. 5 ± 2. 4) × 109/L vs. (11. 7 ± 3. 5) × 109/L,PCT:(1. 2 ± 0. 7) μg/L vs. (2. 3 ± 0. 9) μg/L,CRP:(9. 1 ± 3. 2) mg/L vs. (16. 5 ± 4. 7) mg/L,P<0. 05,respectively]. The total effective rate in the treatment group was significantly higher than that in the control group[93. 1％(94/101)vs. 81. 2％(82/101)]. Mechanical venti-lation duration and PICU stay in treatment group were significantly shorter than those in the control group [(148. 5 ±30. 6)h vs. (159. 6 ±47. 3)h,(220. 8 ±49. 7)h vs. (330. 7 ±94. 6)h]. The positive rate of patho-genic bacteria was significantly higher than that in the control group [79. 2％(80/101)vs. 62. 4％(63/101), P<0. 05],but there was no significant difference in the 28 days mortality of the two groups[5. 0％(5/101) vs. 5. 9％(6/101),P>0. 05]. Conclusion The bronchoalveolar lavage can improve the respiratory func-tion,reduce the inflammatory reaction,shorten mechanical ventilation duration and PICU stay in children with severe pneumonia undergoing mechanical ventilation obviously. It is worth popularizing in the PICU because of the improvement of curative effect in these children.

Objective To explore the role and effectiveness of flexible fiberoptic brochoscopy ( FFB) in critically ill children with continuous invasive respiratory support. Methods From July 2014 to June 2017,135 critically ill children with severe pneumonia had received continuous invasive respiratory sup-port and undergone FFB in the pediatric intensive care unit( PICU) of our hospital. These patients were en-rolled into the therapy group. Another 104 severe pneumonia patients who had not received FFB were enrolled into the control group. Clinical characteristics of both groups were collected and compared. Results No sig-nificant differences were detected in patients′gender, age, PCIS, usage of antibiotics, and the levels of CRP and PCT assayed at the time of admission to PICU between the therapy group and control group(P>0. 05). The positive rate of bacteria culture of the bronchoscopic lavage was 78. 52％( 106 cases ) in the therapy group,and it was significantly higher than that in the control group(60. 58％,63 cases) (χ2 =5. 681,P <0. 005). For 106 cases in the therapy group,117 bacteria strains were identified,while there were 72 bacteria strains found in 63 cases with positive bacteria culture in the control group. Gram negative bacteria were the most common type,followed by Gram positive bacteria. The third most common pathogenic microbes were fungi,with a significantly higher frequency in the therapy group. No significant differences were found in PaO2 and oxygenation index between both groups before FFB. However,in a half hour after FFB,the PaO2 and oxygenation index significantly increased in the therapy group,and higher than those in the control group (P<0. 005). The levels of CRP and PCT assayed before and the first day after FFB were not significantly changed(P>0. 05). But the levels of CRP and PCT in the therapy group significantly decreased in the third day after FFB,and more than those in the control group. Furthermore,duration of invasive respiratory sup-port,and the stay of PICU were significantly shorter in the therapy group(P<0. 005). Conclusion FFB can play an important role in the collection of pathogenic microbes. It also achieves better results in the treatment of severe pneumonia for children in PICU. Therefore,it is worthwhile to be recommended as a safe and feasi-ble intervention in PICU.

Objective To evaluate the feasibility of adaptive statistical iterative reconstruction-V (ASIR-V) to improve image quality in low-dose CT colonography.Methods A series of thirty artificial polyps were established by ligation in an isolated segment of porcine colon.Volume data was acquired on Revolution CT scanner (GE,USA) with High Definition scan mode and different scan parameter combinations:120 kVp with different mAs (10,30,50,70,90,100,120,140,160,180,200,220,240,260,respectively).Images were reconstructed with six different ASIR-V levels of 0 (filtered back projection,FBP),10％,30％,50％,70％ and 90％.Two radiologists were blinded to measure and analyze the objective data independently,including image noise (SD),signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR).The kappa test was used to assess interobserver agreement in subjective image quality score.ICC test was used to examine the consistency of the measurements between two observers.SD,SNR,CNR were performed for statistical analysis in different tube current and different levels of ASIR-V using variance analysis (ANOVA).Results Interobserver agreement for subjective image quality score was good with a kappa value of 0.683.The variation of the tube current(r =0.734,P =0.000) and ASIR-V level(r =0.220,P =0.044) is related to the subjective score of image quality.Under the condition of the same tube current,image quality score of 50％ ASIR-V reconstruction was the highest.Two objective data consistency is good.The differences of image noise (F =423.58,P ＜ 0.05),SNRs(F =124.26,P ＜ 0.05) and CNRs (F =1 030.17,P ＜ 0.05) of different tube current and different levels of ASIR-V reconstruction were statistically significant.In the same tube current,with increased levels of ASIR-V,image noise reduced,CNRs increased.Only in 10,120,140,160,220,240,260 mA,the differences of SNRs were statistically significant(F =8.75-31.36,P ＜ 0.05).For the same level of ASIR-V reconstruction,with the increase of tube current,the image noise decreased,SNR and CNR increased gradually.Conclusions In the CT colonography,the application of ASIR-V algorithm can significantly reduce the noise and enhance the image contrast noise ratio and improve image quality.ASIR-V algorithm with 50％ has better performance in reducing CT image noise.

Objective To investigate the prevalence of pulmonary fungal infection and drug resist-ance of the pathogenic fungi among children with severe diseases in pediatric intensive care unit(PICU). Methods From July 2013 to June 2017,the complete clinical data,results of fungal culture and drug sensi-tivity of bronchoalveolar lavage fluid in 112 critically ill children with pulmonary fungus infection of PICU hospitalization in our hospital were collected. Samples of peripheral venous blood were collected meantime, including blood routine examination,C reactive protein,G test and GM test. Results One hundred and twen-ty-six fungi were isolated from sputum samples in 112 critically ill children. Severe pulmonary infection (30. 36%,34/112) was the most common form of the primary diseases, the next were severe sepsis (16. 07%,18/112)and severe malnutrition(15. 18%,17/112). Classified based on age difference,the first one was ＜1 year old (43. 75%,49/112),the second one was 1 to 3 years old(29. 46%,33/112). The fun-gal strains were predominantly Candida albicans (61. 90%) and Candida tropicalis (16. 67%),among the infectious cases 14 were diagnosed as mixed infection. Two cases of 3 cryptococcal infectious children were HIV infection,another one was malignant tumor,Cryptococcus was cultured in both sputum,pleural effusion and cerebrospinal fluid. The drug resistance rate of fluconazol in 126 strains of fungi was 12. 70%,the rate of itraconazole was 7. 14%. Generally,the fungi cultured were with very low resistance to 5-fluorocytosine,vori-conazole and amphotericin B. However,the strains of Aspergillus fumigates,Candida kruse,Candida parapsi-losis and Cryptococcus were highly resistant to fluconazol and itraconazole,but with very low resistance to 5-fluorocytosine and amphotericin B. Conclusion Candida albicans is the main pathogenic fungus of pulmo-nary fungal infection among children in PICU,and we could choose voriconazole and amphotericin B as treat-ment of critically ill children with pulmonaty fungal infection.

Objective:To explore the disturbance of metal element balance in mice after exposure to radon.Methods:Mice were randomly divided into control group, radon exposure of 30 WLM group, 60 WLM group and 120 WLM groups, with 10 mice in each group. After radon exposure with the cumulative dose, the lung function of mice was detected by a non-invasive pulmonary function testing instrument. Mice blood was taken from eyeballs. The lungs, heart, liver, kidney and spleen were also collected. HE staining was used to observe the pathological changes of lung tissue. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the content of metal elements, including essential trace elements in the body: chromium (Cr), molybdenum (Mo), cobalt (Co), selenium (Se), copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), and potentially toxic elements: arsenic (As), tin (Sn), lead (Pb), aluminum (Al), mercury (Hg), cadmium (Cd), and silver (Ag).Results:Compared with the control group, lung ventilation function of the radon-exposed mice was decreased, alveolar structure was destroyed, and the contents of pulmonary metal elements Cr, Al, Pb, Sn( F=0.34, 0.66, 3.14, 1.16, P<0.05) and essential trace elements Mn, Cr, Zn, and Mo in the blood were decreased( F=0.65, 1.44, 0.97, 2.08, P<0.05), while the elements of Cu, Mo, Se and As in the lungs were increased( F=1.31, 1.26, 0.81, 2.04, P<0.05), and the element contents in other tissues also fluctuated. Conclusions:Inhalation of a certain cumulative dose of radon can reduce the lung ventilation function of mice and induce lung inflammation, as well reduce the content of essential trace elements in the lung and blood so that the content of metal elements in the body fluctuates.

Objective:To investigate the risk factors and clinical significance of lymph nodes metastasis between sternocleidomastoid and sternohyoid muscle lymph node (LNSS) metastasis in thyroid cancer patients, so as to guide the reasonable dissection of LNSS region and lateral cervical lymph node in patients with papillary thyroid carcinoma (PTC) .Methods:We selected 111 PTC patients with lateral cervical lymph node metastasis who underwent radical thyroidectomy and lateral cervical lymph node dissection from Nov. 2018 to Dec. 2021 in China-Japan Union Hospital of jilin university. All patients were treated with low collar arc incision. Radical thyroidectomy and lateral cervical lymph node dissection were performed according to the guidelines, and lymph nodes in each district were grouped for pathological examination. According to whether LNSS metastasis occurred, they were divided into two groups: LNSS positive group (LNSS metastasis occurred) and LNSS negative group (LNSS metastasis did not happen). We collected the basic information of all 111 PTC patients with lateral lymph node metastasis (LLNM), preoperative color Doppler ultrasound examination and paraffin-embedded pathology and other related clinical case data. Then we described the clinicopathological features of cervical lymph node metastasis. Independent sample t test and Mann-Whitney U test were used for continuous variables, and Fisher exact test was used for data analysis for classified variables. Correlation analysis adopted binary logistics regression model, and analyzed the regularity and risk factors of LNSS metastasis. Results:In this study, the detection rate of LNSS was 64.9% (72/111), the overall LNSS metastasis rate was 7.2% (8/111), and the number of lymph node metastasis was 0-5. Univariate analysis showed that the location of LNSS metastasis was related with the cancer focus ( P<0.001), the preoperative serum thyroglobulin (Tg) level ( P=0.002), the number of lymph node metastasis in lateral cervical level Ⅳ ( P=0.001), the longest diameter of the cancer focus ( P=0.003) and the longest diameter of metastatic lymph nodes ( P=0.001) However, age, sex, whether there is lymph node metastasis in the central region (central lymph node metastasis ,CLNM), and whether there is multifocal cancer were not related to LNSS metastasis ( P≥0.05). Further multivariate analysis and work curve analysis of subjects showed that the tumor located in the lower pole ( P=0.014) and the number of lymph node metastasis in level Ⅳ more than 3 ( P=0.027) were independent risk factors for LNSS metastasis. It was found that the risk of LNSS metastasis increased when the cancer focus was located at the lower pole relative to the upper pole or middle part of the cancer focus ( OR=74.508, 95% CI: 2.373-2339.544). The number of lymph node metastasis in level Ⅳ had a positive effect on LNSS metastasis. The more lymph node metastasis in level Ⅳ, the higher the risk of LNSS metastasis ( OR=1.556; 95% CI=1.051-2.303) . Conclusions:In PTC patients with LLNM, the LNSS metastasis rate was 7.2%, and the advantages of LNSS cleaning outweigh the disadvantages. When the cancer focus is located at the lower pole and the number of lymph node metastasis in region Ⅳ is more than 3, it is necessary to pay attention to the dissection of this group of lymph nodes.