Objective To investigate the feasibility of diffusion-weighted(DWI) MRI on basis of the intravoxel incoherent motion (IVIM) in nasopharyngeal carcinoma (NPC),and the diagnostic value of pure molecular diffusion coefficient (D),perfusion-related diffusion coefficient (D *) and perfusion fraction (f) in first onset NPC.Methods From December 2011 to January 2013,40 consecutive patients (26 men,14 women; median age,52 years) with suspected NPC were examined on a 3.0 T MR scanner.DW imaging was performed by using a single-shot echo-planar sequence with 13 b-values (0,10,20,30,50,80,100,150,200,300,400,600,800 s/mm2).MR imaging was compared with endoscopy and biopsy for the detection of NPC.Mean interval time between MR imaging examination and subsequent nasopharyngeal biopsy was 3 days (range,0-11 days).The subjects were divided into 2 groups according to the pathological results,group A was subjects with NPC (17 men,9 women; median age,35) and group B was ones with nasopharyngeal chronic hyperplastic inflammation(NPH) (9 men,5 women; median age,35).The D,D * and f were measured and compared in patients with first onset NPC and nasopharyngeal hyperplasia (Mann-Whitney test).Results IVIM DWI was successful in 24/26 with NPC and 12/14 with NPH.D value was significantly lower in A group compared with B group [mean,(0.70 ± 0.13) ×10-3 mm2/s vs (0.78 ± 0.05) × 10-3 mm2/s ; U =2.05,P ＜ 0.05],as was f value [mean,(16.25 ±1.46) ％ vs (26.20 ± 3.90) ％ ; U =11.16,P ＜ 0.01].However,D* value was significantly higher in Agroupas compared with B group[mean,(161.8 ±23.56) × 10-3 mm2/s vs (55.28 ± 17.05) × 10-3 mm2/s; U =13.90,P ＜0.01].Conclusions IVIM DWI is a feasible technique for investigating first onset NPC and D value has a certain value in differentiating NPC and NPH.D* value has an important potential value in distinguishing benign and malignant NPC.

Objective To analyze the risk factors of nosocomial infection in Department of Neurosurgery and to provide evidence for the prevention and treatment of infection.Methods A total of 931 patients with neurosurgery operation in our hospital from January 2012-January 2016 were collected medical history data immediately after admission,including age,gender,underlying diseases,and primary diseases.Surgical records include preoperative white blood cell count,blood glucose level before operation,duration of operation,and reoperation.Hospitalization records include hospitalization time,without the use of corticosteroids,with or without the use of proton there is no pump inhibitor,and tracheal intubation / incision.Patients were divided into infection group and non infection group according to whether the hospital infection occurred during hospitalization.The difference of two groups of clinical data with statistically significant variables was Logistic multivariate regression analysis.Results There were 112 patients with nosocomial infection,the infection rate was 12.03％,and the infection occurred in the postoperative 3-25 d.The main infection site was postoperative wound,accounting for 35.7％;respiratory tract,accounting for 34.8％.There were 64 strains of pathogenic bacteria,81 strains of Gram-negative bacteria,accounting for 64.1％,21 strains of gram positive bacteria,accounting for 32.8％,2 strains of fungi,accounting for 3.1％.There were significant difference between infection group and non infection group in ≥ 60 years,with basic diseases,reoperation,combined with other injuries,white blood cells,abnormal preoperative hyperglycemia,glucocorticoid use,proton pump inhibitors use,tracheotomy,hospitalization time,operation time (P ＜ 0.05).Further Logisitc regression analysis showed that age,reoperation,hospitalization time,preoperative high blood sugar and tracheotomy were the risk factors of nosocomial infection in Department of neurosurgery.Conclusions For the older,reoperation,longer hospitalization time,preoperative hyperglycemia and tracheotomy patients can take specific measures to improve the immunity of the patients,the rational use of antimicrobial drugs to avoid the occurrence of postoperative infection.

ObjectiveTo explore the effects of sacral neuromodulation using a new tined-lead electrode on neurogenic bladder.MethodsThe use of a new tined-lead electrode for sacral neuromodulation was evaluated in a study including 5 consecutive patients with neurogenic bladder.The tined leads were implanted at the S3 foramen under the X-ray screening.Subjects completed the recording of detailed voiding diary pre-and post-operation including fluid intake,voided volume,leaked volume,catheterized volume,frequency,accompanying symptoms and sensation.Vesicourethral function was assessed by video-urodynamics.ResultsUrinary frequency and voided volume were improved 22% and 49% respectively in one patient with spinal bifida.Urinary frequency,voided volume and residual volume were improved 0.7%,11% and 46% respectively in another one.Urinary frequency,voided volume and residual volume were improved 0.4%,18% and 44% respectively in the third one.Frequency of leakage and leaked volume were improved 36% and 54% respectively in the patient with brain trauma.Frequency of CIC and catheterized volume were improved 42% and 54% respectively,and indexes of urodynamics were improved 37%～45% in the patient with spinal cord injury.ConclusionA new tined-lead electrode for sacral neuromodulation provide a new alterative and minimally invasive procedure to treat neurogenic bladder.

Objective To investigate the variation characteristics of adenovirus type 55 (HAdV-B55) gene on plateaus.Methods Throat swabs were collected from HAdV-B55 infected patients and used for virus isolation in HEp-2 cells.The whole-genome sequence was obtained by PCR and sequencing.HAdV-B55 gene sequence was blast with the previously reported virus.Results HAdV-B55 strains were isolated from throat swabs, which were named LS89/Tibet/2016.The whole-genome sequence was obtained and submitted to GenBank with the accession number of KY002683.No large fragment gene recombination was found between this HAdV-B55 strain and previous strains, and the sequence similarity with QS-DLL strain was 99.9%.Conclusion This study provides more information for the evolution patterns of adenovirus 55 and will contribute to the prevention and control of HAdV-B55 infection in the future.

Objective To compare the relative dose of small fields measured by clinically common detectors and those obtained from Monte Carlo simulation in order to obtain the accurate measurement method, and to modify the inappropriate detectors.Methods The percentage depth-dose distribution curve and profile (flatness and symmetry) curves were collected at 2 cm×2 cm, 3 cm×3 cm, and 4 cm×4 cm under 6-MV X-ray of Trilogy linear accelerator by CC13, PFD, SFD, and blue phantom.The results were compared with the stimulation results from Monte Carlo method (the current gold standard).The correction factors for the detectors with large error were calculated to provide reference data for clinical practice.Results The results measured by SFD detector were most close to the results from Monte Carlo simulation.The measurement errors of CC13 and PFD detectors were large.The correction factor in the penumbra for CC13 and PFD detector was 0.664-1.499.Conclusions SFD detector is better than CC13 and PFD detector in the measurement of small fields, but CC13 and PFD detector can provide reference data for clinical practice after the corresponding correction.

BACKGROUND: At present, there is no consensus on the effect of different dressings in the healing of donor site, and few studies have directly compared the healing effect of different dressings. OBJECTIVE: To evaluate the healing effect of five different dressings on donor site wounds by network meta-analysis. METHODS: Randomized controlled trials about different dressings in the treatment of donor site wounds were retrieved by computer in PubMed, EMBASE, Cochrane, Chinese Academic Journal Full Text Database, Chinese Biomedical Literature CD-ROM Database, WanFang Data Platform and Chinese Science and Technology Journal Database. The retrieval time limit was from inception until May 2018. Literature screening, quality evaluation and data extraction were conducted independently by two postgraduates. Winbugs 1.4.3 and Stata 13.0 softwares were used for data analysis. RESULTS AND CONCLUSION: A total of 13 randomized controlled trials were included. In the observation group, foam dressing, hydrocolloid dressing, alginate dressing or silver dressing was used. In the control group, vaseline gauze was used. The results of network meta-analysis showed that the healing time of donor sites for alginate dressing, silver dressing, hydrocolloid dressing and foam dressing was significantly shorter than that of vaseline gauze (P < 0.05) , but there was no difference in wound healing time between foam dressing, hydrocolloid dressing, alginate dressing and silver dressing at the donor site (P> 0.05) . The healing effects of different dressings were ranked as follows (from good to bad) : alginate dressing, silver dressing, hydrocolloid dressing, foam dressing and vaseline gauze. Overall findings indicate that alginate dressing may be the best choice to shorten the healing time of donor site, and further investigations are warranted.

OBJECTIVE To study the roles of iron and zinc in the pathogenesis of recurrent tonsillitis and tonsillar hypertrophy.METHODS In total,40 patients who underwent a tonsillectomy to treat chronic tonsillitis or tonsillar hypertrophy were included in the study.Patients were divided into 2 groups,chronic tonsillitis or tonsillar hypertrophy group.The levels of iron and zinc elements were measured for each tonsillar tissue sample.RESULTS There was a significant difference in the iron and zinc level (P＜0.001) between the tonsillar hypertrophy and chronic tonsillitis groups.The levels of iron and zinc were significantly lower in the chronic tonsillitis group.CONCLUSION The results suggest that low tissue concentration of iron and zinc may lead to chronic tonsillitis.

Objective To explore the relationship among peer relationship,self-consciousness and social anxiety in HIV-infected children. Methods Peer Relationship Scale,Piers-Harris Children's Self-con-cept Scale and Social Anxiety Scale for Children were applied to 126 HIV-infected children. Results The score of peer relationship was 53. 0(45. 0,62. 0),the score of self-concept was 52. 0(42. 0,60. 0),and the score of social anxiety was 6. 0(2. 0,9. 0). Peer relationship was positively correlated with social anxiety( r=0. 196,P=0. 029) and negatively correlated with self-consciousness(r=-0. 628,P<0. 01). Self-conscious-ness was negatively correlated with social anxiety(r=-0. 504,P<0. 01). Bootstrap analysis showed that self-consciousness played a complete mediating role between peer relationship and social anxiety,and the media-ting effect value was 0. 377. Conclusion Peer relationship,self-consciousness and social anxiety are closely related. Furthermore,self-consciousness plays a complete mediating role between peer relationship and social anxiety in HIV-infected children.

Abstract:To compare the morphology of spinal cord between healthy adolescents with adolescent Chiari malformation type I (CMI) patients and investigate the impact of syringomyelia on the morphology of spinal cord in CMI patients.Methods:The clinical and radiological data of 292 CMI patients diagnosed by our center between June 2012 and March 2019 were retrospectively reviewed. Among them 15 CMI patients without syringomyelia were recruited in the CM group. Among the remaining 277 CMI patients, 274 patients had syringomyelia below the C 3-4 intervertebral disc. According to the principle of best matching, CMI patients with syringomyelia were selected with the closest age to the CM group (±18 months), and 30 CMI patients with syringomyelia were included in the CMS group according to a ratio of 1∶2. Thirty healthy adolescents were enrolled as the control group (NC group) in the same way. The anteroposterior diameters of spinal cord at C 2 (DSCO-C 2), spinal canal at C 2 (DSCA-C 2), midbrain-pontine junction (DPJ), the distance between the tip of cerebellar tonsils and the foramen magnum (AB) and the maximal diameter of the syrinx (D-syrinx) were measured on MRI. All radiographic parameters were measured twice independently by two spine surgeons, and intraclass correlation coefficient (ICC) were determined to demonstrate intra- and inter-observer reliability. One-way ANOVA and SNK- q test were used to compare the above radiographic parameters and age between CM, CMS and NC group. The distribution of genders was compared between the three groups using Chi-square tests. Pearson correlation analysis were conducted to demonstrate the relationship between radiographic parameters in CM and CMS group. Results:ICC ranged between 0.91 and 0.95 in the current study, demonstrating "excellent" reliability of radiographic measurements. No significant difference was noted regarding age and the distribution of genders among the three groups. Patients in CM and CMS groups showed similar DSCO-C 2 values ( P=0.254), both of which were significantly lower than that in NC group ( P<0.001). DSCA-C 2 in CMS group was significantly larger than that in CM ( P=0.003) and NC ( P<0.001) groups, while no significant difference was found between the CM and NC groups ( P=0.216). Moreover, DPJ in CMS group was significantly lower than that in CM group ( P<0.001) and NC group ( P<0.001). There was no significant difference in AB between CM and CMS groups ( P=0.948). DSCO-C 2 was significantly positively correlated with DSCA-C 2 in CMS group ( r=0.906, P<0.001), while AB, D-syrinx, DSCO-syrinx, DSCA-syrinx and DPJ were not significantly correlated with DSCA-C 2. There were significant correlations observed between DPJ and other radiographic parameters in the CMS group (all P>0.05). Significant positive correlation between DSCO-C 2 and DPJ was observed in CM group ( r=0.703, P=0.005). There was no significant correlation between DSCO-C 2 and DSCA-C 2 and DPJ in NC group (all P>0.05). Conclusion:CMI adolescents have significant atrophic change of cervical spinal cord and midbrain-pontine junction compared with healthy adolescents, regardless of the existence of syrinx. Moreover, syrinx in CMI patients indicated more obvious atrophic change of midbrain-pontine junction and dilated spinal canal compared with isolated CMI patients.

Objective To explore and establish accurate detection quality control method of source positioning and timer precision for afterloading equipment. Methods The source positioning detection device was made of hd camera,EBT3 disposable film and steel rule,collecting source in each resident point for video images and film. Accurate measurement of radioactive source positioning and timer accuracy, including the timing absolute error and linear error through analysis of image sampling rate. After the film grayscale distribution analysis,comparison between film gray peak position and the measurement of resident point geometry,got the stay point source physics and radiation center deviation. Results Radioactive source physics and radiation center deviation was (-0.33± 0. 10) mm;For all default dwell time,timer average absolute deviation was (0.22±0. 02) s,linear fitting result was y=x-0. 226,R2=1,timing linear error was-0. 01％ Conclusions established detection means through the video images and film exposure quantitative analysis for accurately determination of source positioning,dwell time and source radiation center precision. After experimental testing the machine precision satisfied the requirement of clinical use.