Purpose To evaluate the added value of time of flight(TOF)and point spread dispersion(PSF)reconstruction in mediastinal lymph node metastasis of lung cancer in 18F-FDG PET/CT imaging.Materials and Methods Sixty-eight lung cancer patients with mediastinal lymph node metastasis who underwent PET/CT examination in the First People's Hospital of Foshan from March 9,2020 to July 23,2021 were analyzed retrospectively.The different methods,including ordered subsets estimation maximization(OSEM),OSEM+TOF,OSEM+PSF,OSEM+TOF+PSF,were used to reconstruct the images.The resolution of different reconstruction algorithms for mediastinal lymph node metastasis of lung cancer,as well as the differences of signal-to-noise ratio(SNR)and standard uptake value(SUV)were compared,respectively.Results The highest values of SUVmean,SUVmax and SNR were obtained via OSEM+TOF+PSF method,which increased by 21.99%,22.86%and 60.14%,compared with conventional OSEM method(t=28.321,19.11,11.059,all P<0.01).The difference percentage in smaller lesions that diameter≤22 mm was significantly higher than that in larger lesions that diameter>22 mm(24.1%vs.21.1%,25.3%vs.19.3%,70.6%vs.63.3%;Z=-3.658,-4.313,-2.154,all P<0.05),and the difference percentage in low contrast lesions that SNR≤15.31 was significantly higher than that in high contrast lesions that SNR>15.31(23.6%vs.21.4%,25.3%vs.21.1%,85.7%vs.46.0%;Z=-3.519,-2.336,-5.106,all P<0.05).Among the evaluation results of lesion detectability of different reconstruction algorithms,OSEM+TOF+PSF image showed the mediastinal lymph node metastasis most clearly(87.4%of the lesions were clearly existing),which was significantly higher than that of OSEM image(73.1%of lesions were clearly existing)(χ2=11.704,P=0.001),however,the proportion of lesions clearly existing in OSEM+PSF image did not significantly increase compared with OSEM image(73.1%vs.75.8%;χ2=0.361,P=0.548).Conclusion The combination of TOF and PSF can significantly improve the detection ability,SNR and SUV of mediastinal lymph node metastasis of lung cancer,especially in small and low contrast lesions.

ObjectiveTo screen out the mRNAs involved in the resistance of hepatoma cells to anlotinib using ceRNA microarray. MethodsHigh-dose shock combined with low-dose induction was used to culture hepatoma cells resistant to anlotinib, and CCK8 assay was used to verify the difference in the proliferation of drug-resistant hepatoma cells treated by anlotinib. The ceRNA microarray was used to screen out the differentially expressed genes between drug-resistant hepatoma cells and normal hepatoma cells, and real-time PCR was used to verify the differentially expressed genes detected by some microarrays. the independent samples t-test was used for comparison of continuous data between two groups, and the Kaplan-Meier method was used to analyze the overall survival of hepatoma cells samples, and the log-rank test was used to compare survival rates. Fisher’s exact test was used for chip screening. ResultsThere was a significant difference in gene expression between drug-resistant hepatoma cells and normal hepatoma cells, and 10 genes with the greatest difference were screened out for analysis by reducing the range. There were 4 genes associated with drug resistance and tumor growth, i.e., BIRC2, BIRC7, ABCC2, and MAPK8. There were significant reductions in the expression levels of BIRC2, ABCC2, and MAPK8 (P=0001 4, 0001 2, and 0.011 8), and there was a significant increase in the expression of BIRC7 (P＜0.001). The results of real-time PCR were consistent with those of microarray (t=10.74,32.65,18.34, and 2.80; P=0.000 4, 0.000 1, 0.000 1, and 0.044 8). The high expression of BIRC7 and the low expression of MAPK8 were associated with the significant reduction in survival time (P=0.022 0 and 0.005 6). ConclusionBIRC2, BIRC7, ABCC2, and MAPK8 are differentially expressed between anlotinib-resistant hepatoma cells and normal hepatoma cells and may be involved in the resistance of hepatoma cells to anlotinib.

Objective:To explore the accuracy of determination of the pathogen in children with lower respiratory infection according to sputum properties and the selection of corresponding antibiotics.To analyze the relationship between children's age, length of hospital stays and sputum culture positive rate.Methods:From March 2015 to November 2016, 300 children with lower respiratory infection in the Seventh Affiliated Hospital of Guangxi Medical University were selected.The isolated sputums through the nasal cavity were cultured, the sputum properties and antibiotics used at the beginning and 3-4 days later(after sputum culture) were recorded.Results:The sputum culture showed that 110 of 300 cases with lower respiratory infection were positive.Main pathogens were streptococcus pneumoniae, E.coli, staphylococcus aureus, klebsiella pneumoniae subspecies.Compared with the children with positive sputum culture, for white phlegm sputum and yellow phlegm sputum, the children with sputum culture negative had higher accuracy of antibiotic use(white phlegm sputum: 64.4%, yellow phlegm sputum: 57.1%), the difference was statistically significant (χ 2=36.04, P<0.01). The bacteria positive rate and multiple resistance rate had no statistically significant differences in length of treatment time prior to admission(all P>0.05). However, the bacteria positive rate (hospital stay ≤7 d: 24.7%, hospital stay>7 d: 48.1%, χ 2=17.66) and multiple resistance rate (hospital stay≤7 d: 13.9%, hospital stay>7 d: 35.1%; χ 2=5.40) had statistically significant differences in the length of hospitalization(all P<0.05). The bacteria positive rates in different age groups were as follows: 1-6 months: 48.1%, >6-36 months: 28.3%, >36 months: 25.0%.Compared with the two others, the positive rate of 1-6 months was higher and had statistically significant difference (χ 2=13.64, P<0.05). Conclusion:Accuracy of antibiotics use has a certain relationship with sputum color or properties and the result of sputum culture, for white phlegm sputum and yellow phlegm sputum, the accuracy of antibiotics use is higher.Once identified pathogen, sensitive antibiotics should be adopted.Probably, bacteria positive rate and multiple resistance rate have a certain relationship with the length of hospital stay and age.

Objective: To observe the influence of lower wide pedicle frontal periosteum flap on frontal bone absorption rate after cranioplasty. Methods: From February 2016 to July 2017, the lower wide pedicle frontal periosteum flap was produced in 12 patients of Shanghai Ninth People′s Hospital (7 males/5 females, aged 5-9 years, 10 hypertelorism, 2 Crouzon syndrome), who accepted intro-cranio-route plastic surgery, to cover the frontal bone window. A spiral CT scans were applied one week (t1) and one year (t2) after surgery. DICOM data was imported into Mimics software to reconstruct the 3D model of skull. The bone window covered the frontal bone was selected and the bone volume was calculated. The absorption rate was calculated as (Vt₁-Vt₂)/Vt₁×100%. As a control group, the CT data of 20 patients (from January 2010 to December 2015, 11 males/9 females, 7 hypertelorism, 12 Crouzon syndrome, 1 Pfeiffer syndrome) were analyzed retrospectively in the same way, and compared to the experimental group. Results: The average bone absorption rate in experimental group was 8.65%±2.56% (n=12), while in control group it was 26.51%±5.23% (n=20). Significant statistical difference was observed. No further cranial defect was observed in one-year follow-up in both two groups. Conclusions The lower wide pedicle frontal periosteum flap reduces the bone absorption rate after intro-cranio-route plastic surgery. It could also help to repair the anterior cranial base defect during the surgery. This technique was recommend as a regular step in craniofacial surgeries.

In order to establish the minipig model of chronic myocardial ischemia and apply non-invasive telemetry technique, the minipig model of chronic myocardial ischemia was made induced by Vitamin D3, isoproterenol and combined with high fat diet, and the non-invasive telemetry technique was used to detect and evaluate the symptoms of minipig model of chronic myocardial ischemia.Moreover, the effects of transport stress and the risk factors of atherosclerosis (AS) induced by high fat diet among Wuzhishan minipigs, Bama minipigs and Tibetan minipigs were also evaluated.Our study has successful established the Bama minipig model of chronic myocardial ischemia and the technical specification for evaluation,.The non-invasive telemetry technique can be used to detect and evaluate the symptoms of chronic myocardial ischemia model, and defines minipigs at least need to keep for more than 4 weeks after transport stress to adaptive recovery period.In addition, the different characteristics of AS risk factors such as hyperlipidemia, hypertension and hyperinsulinemia were observed in Wuzhishan minipigs, Bama minipigs and Tibetan minipigs in high fat environment, and this provides a reference for the selection and application of minipigs in the research of cardiovascular diseases.

Objective To explore the value of practicing PBL which was guided by MDT in teaching diagnoses and treatments of war wound and trauma caused by compound agents.Methods An emulational war wound case caused by compound factors was designed and a multi-disciplinary team been organized,then totally 45 interns who would graduate in 2017 were divide into two groups randomly,experimental group which had 23 cases received PBL model combined with MDT followed six step procedure which included case preparation by teachers,independent analysis and group discussion by interns,problem extraction by teachers and division of solution by interns before class,then answering and debating problems by interns in class,conclusion and reporting after class in the end,while the control group which had 22 cases received traditional teaching model in accordance with common case discussion in class including characteristics of patient,diagnosis and diagnostic basis,examinations needed to carry out,first aid measures and professional treatments.The effect of new teaching model was evaluated by assessment in class and questionnaire after class.The data was analyzed through Chi-square test by SPSS 22.0.Results Class assessment showed 18 (78.3％) interns in experimental group displayed good abilities of proposing,analyzing and resolving medical problem,as well as good presentation and speech skills.Questionnaire survey showed that not only clinical teaching of war wound and trauma could meet the demands of talent training in battle-field rescue,but also displayed new model,which could help interns to enhance abilities of first-aid and treatment of war wound on future war field,reinforce the consciousness of military medical support and service.In addition,it could clear confusion more professionally and strengthen teamwork and overall importance.Conclusion Applying PBL combined with MDT in teaching diagnoses and treatments of war wound and trauma can not only help interns to review and retain important knowledge of related subjects,but also improve the abilities of interns in clinical diagnoses and treatments,and moreover,it merges the medical knowledge and war wound cure together organically.In short,the new model is well worth applying in clinical teaching and military medical education because of its excellent effects.

Objective To analyze the genetic variation among white hair black eyes (WHBE) rabbit, Japanese white ( JW) rabbit and New Zealand white ( NZW) rabbit using random amplified polymorphic DNA ( RAPD) technique . Methods Thirty rabbits (male/female 1∶1) of each strain were used in this study.The genomic DNA was extracted from 90 rabbits.Sixty arbitrary primers were used to amplify DNA of rabbits with RAPD-PCR method.Based on the preliminary experiments , polymorphic primers were selected to analyze the genetic variation among the three rabbit strains .The experi-mental data were analyzed using Popgene 3.2 software.Results (1) Twenty-five polymorphic primers were selected among 60 arbitrary primers.493 amplified fragments were detected ranging from 100 bp to 1800 bp.Sixteen primers among 25 arbitrary primers could not only amplify the common DNA bands of 3 rabbit breeds , but also amplify particular alleles in the WHBE rabbit.(2) 234 RAPD sites were detected by agarose gel electrophoresis in WHBE rabbit , among which 166 sites were polymorphic , accounting for 70.94%.228 RAPD sites were detected by agarose gel electrophoresis in the JW rabbit, while 122 sites of them were polymorphic , accounting for 53.51%.231 RAPD sites were detected by agarose gel e-lectrophoresis in the NZW rabbits , with 94 sites being polymorphic, accounting for 40.69%.(3) The Shannon genetic di-versity index of WHBE rabbit, JW rabbit and NZW rabbit was 0.3385, 0.2222 and 0.1905, respectively.(4) The genet-ic similarity between JW rabbit and NZW rabbit was highest among the three rabbit breeds (0.8443), followed by that be-tween WHBE rabbit and JW rabbit (0.8204), and the genetic similarity between WHBE rabbit and NZW rabbit (0.7862) was the lowest .Conclusions Our results demonstrate that there are both genetic similarities and genetic variations among WHBE rabbit, JW rabbit and NZW rabbit .The RAPD technique can be used to delect the genetic relationships among dif-ferent breeds and different individuals of the same breed of rabbits .

Objective To explore the value of right lateral decubitus position MPI for differentiating myocardial perfusion defect from cardiac anterior wall attenuation artificial defect,caused by breast of woman.Methods Forty-nine patients(average age (61.5±8.4) years) who had low likelihood of coronary artery disease and had perfusion defect in the anterior wall after exercise stress 99Tcm-MIBI MPI were included.All underwent supine and right lateral decubitus position during resting SPECT images.The myocardial perfusion SPECT images at left ventricle were reconstructed and were measured by Bull's-eye,based on the counts.Results from both supine position imaging and right lateral decubitus position imaging were compared.Paired t test was used to statistically analyse the data by SPSS 13.0.Results Compared with supine position,the counts of the anterior,inferior,apex and lateral wall in right lateral decubitus position were significantly higher:(71.30±3.53) ％ vs (66.50±3.85) ％,(70.06±4.45) ％ vs (65.44±4.16) ％,(77.90±3.00)％ vs (75.81±4.08)％,(79.30±2.26)％ vs (72.60±3.87)％ (t=6.731,5.286,3.555,10.885,all P＜0.01).The counts of septal wall were significantly lower ((66.60±3.98)％ vs (70.06±4.51)％,t=-4.625,P＜0.01) in right lateral decubitus position than that in supine position.Among the different regions of anterior wall,the counts of the anterior-middle ((76.40 ± 3.80) ％ vs (68.60 ± 4.76) ％) and anterior-apex region ((77.10±3.24) ％ vs (69.00±3.54) ％) were significantly higher (t =9.916,8.870,both P＜0.01) in right lateral decubitus position than those in supine position,but there was insignificance ((56.94±6.06)％ vs (58.50±4.98) ％,t =-1.493,P＞0.05) at anterior-basal region.The artificial defect of different degrees in anterior wall was observed in all patients in supine position,23 cases (46.9％,23/49) showed artificial defect in the anterior-middle region and 16 cases (32.7％,16/49) in the anterior-apex region.All artificial defect showed radioactive filling in right lateral position imaging,12 cases(24.5％,12/49) filled markedly and 32 cases(65.3％,32/49) filled completely.Conclusions The artificial defects caused by breast of woman mainly present in anterior-middle region and in anterior-apex region of the anterior wall in supine position imaging.The right lateral decubitus position imaging can markedly improve these artificial defects.

Objective To evaluate the effects of different reconstruction algorithms on image quality for Philips GEMINI PET/CT. Methods Jaszczak phantom were scanned on the GEMINI PET/CT system, and the raw data were reconstructed using filtered-back projection with Hanning filter (FBP-Hanning), filtered-back projection with Butterworth filter (FBP-Butterworth), ordered subset expectation maximization (OSEM), row-action maximum likelihood algorithm (RAMLA) and three-dimensional row-action maximum likelihood algorithm (3D-RAMLA), respectively. The resolution, uniformity, contrast of images and the time of different reconstruction algorithms were compared. Results The reconstruction time was 180 s, 130 s, 120 s, 85 s and 80 s for 3D-RAMLA, RAMLA, OSEM, FBP-Hanning and FBP-Butterworth respectively in phantom studies. The smallest rods with diameter of 4.8 mm of the phantom could be observed for FBP- Butterworth and 6.4 mm for other algorithms in case of high counts. The image contrast of 3D-RAMLA were better than that other algorithms, and the image uniformity of 3D-RAMLA and RAMLA were better than those of other algorithms. The resolution, uniformity and contrast of images with all algorithms decreasd in case of low counts, and the image quality of FBP-Butterworth was not good enough for clinical studies. Conclusion Image quality is variable with different reconstruction algorithms. For clinical PET imaging, it is necessary to choose proper algorithms.

OBJECTIVE To investigate the incidence of nosocomial infection in ICU patients,risk factors.and measures to prevent infection.METHODS The nosocomial infection of ICU patients in the hospitals from Nov 2005 to Jun 2009 was investigated using the method of target monitoring.The nosocomial infection rate was regulated by the method of ASA.The invasive procedure and the associated infection rate were analyzed.RESULTS Among 833 inpatients in ICU,92 suffered from nosocomial infection,The nosocomial infection rate was 11.04%.and the nosocomial infection rate per day was 4.43% after modified by the method of ASA.The incidence of patients was 5.37%.Totally 145 strains of bacteria were isolated,and the dominant pathogens were Gram-negative bacilli(56.55%).CONCLUSIONS The patients in ICU are susceptible population of nosocomial infection,A.baumannii is the dominating pathogen to cause nosocomial infection in intensive care units.Target monitoring in ICU is an effective surveillance method to reduce the prevalence of nosocomial infection.