Objective To compare the accuracy of output factor calculation for rectangular inserts of electron beams by using three kinds of algorisms: square root, one dimensional formula and area periphery ration. Methods The differences between the values of output factor calculated by these three algorithms mentioned above and the results measured by ionization chamber for seven rectangular inserts were compared. Results When beam energy was fixed, the difference between calculated and measured output factors was larger for area periphery ration algorithm than that of the square root or one dimensional formula algorithms. The electron cone size, beam energy and rectangular inserts size all had some effect on the value of output factor calculated by the three algorithms. Conclusions The area periphery ration algorithm is not recommended for clinical use because of its great deviation. One dimensional formula and square root algorisms possess a good accuracy. One dimensional formula is superior to square root algorithm, but square root algorithm is more practical for clinical use.

Objective To explore the value of echo-tracking technique in the detecting the ipsilateral external iliac artery elasticity after gunshot wound in pig limbs.Methods Two-dimensional ultrasound imagings and elasticity parameters of external iliac artery of fifteen pig limbs were obtained respectively,and the results were compared with pre-injury groups.The animals were sacrificed after ultrasonography.Pathological examinations of adjacent external iliac artery of injured pig limbs were analyzed.Results Two-dimensional ultrasound imagings of external iliac arteries had no significant changes post-injury.The changes of elasticity parameters were significiant differences in the injured group comparing with the pre-injured group (P ＜0.05),including the increased stiffness parameter(β),pressure-strain elasticity modulus (Ep)and the decreased arterial compliance(AC).Pathological result showed that the internal elastic lamina of artery detected were flat,endothelial cells came off discontinuously and structure of them were undefined.Conclusions Echo-tracking technique can find the elastic changes of adjacent artery indirect injured by gunshot wound sensitively and which can suggest the occurrence of vascular indirect injury.

Objective To analyses the magnetic resonance imaging(MRI)findings of different clinical patterns of neurosyphilis(NS).Methods Clinical records and MRI of 26 patients with NS were retrospectively studied.Results Abnormal MRI was found in 17 patients of 26 patients with NS.In 7 patients were with meningo-vascular syphilis,the MRI commonly showed multiple cerebral ischemia focus and cerebral infarction focus,very few similar to those of encephalitis;Six patients had general paresis,who presented cerebral MRI abnormalities of frontal and temporal atrophy,and few simultaneously with cerebral ischemia focus,granular apendymitis and hippocampus sclerosis;Three patients had syphilitic myelitis,their MRI showed mild tumefaction with multiple ischemic focus all the way through lower cervical spinal cord to lower thoracic spinal cord:One patient was with tabes dorsalis,whose cerebral MRI showed ischemic locus.Another 9 patients had normal MRI,of whom 4 patients with meningitis NS and 5 with tabes dorsalis.Conclusion The MRI of neurosyphilis has diverse presentations,and clinicians should pay much attention to it.

Objective To explore the specific ultrasonic manifestation features of intracranial foreign bodies after firearm injury,and to evaluate the value of ultrasonography in detecting intracranial foreign bodies.Methods ① The specific ultrasonic manifestation features of intracranial foreign bodies were summarized by making ultrasonic scanning over known foreign bodies of different types inserted before hand in around the injury tracts.②With the summary,ultrasonic scanning was made to the foreign bodies with unknown size and types,the result was confirmed with the fetched-out foreign bodies,and the coincidence of ultrasonography in scanning the intracranial foreign bodies after firearm injury was evaluated.Results Ultrasonography could distinguish intracranial foreign bodies from brain parenchyma,intraeranial foreign bodies of different types had different ultrasonic manifestation features.The size and the materials of the foreign bodies had certain affection on the result of ultrasonic scanning.The accuracy of qualitative judgement in scanning the intracranial foreign bodies was 71.52％,and the accuracy in scanning the foreign bodies with diameter ＞ 0.5 cm was higher than that with the diameter ＜ 0.5 cm.The coincidence in qualitative judgement of the foreign bodies of different materials ranged as follows:bullet (97 ％ )＞ steel ball (81.13％),bone pieces (78％) and glasses (72％) ＞gauze (54.67％) and wood pieces (54.67％).Conclusions The intracranial foreign bodies of different materials have specific ultrasonic manifestation features and ultrasonography can scan out their locations.The coincidence of qualitative judgement in scanning the bodies with diameter over 0.5 cm is high.Ultrasonography may be of important significance in guiding the fetch-out of intracranial foreign bodies on the spot and in raising the rescuing level of firearm injury.

Objective To explore the ultrasonographic characteristics in craniocerebral gunshot injured areas and the value of ultrasound technology for judging the activity of wound tissues. Methods After establishment of the model of penetrated craniocerebral gunshot wound, the ultrasonographic characteristics of the tissues in the injured areas were observed by conventional ultrasound and contrastenhanced ultrasonography(CEUS) ,and compared with the pathological changes of the wound area. Results ①A straight-looking, irregular-edged, easily distinguishable pipe-shaped high-level echo can be seen by conventional ultrasound in craniocerebral gunshot injured areas. ②The pipe-shaped strong echo usually shows non-enhancement by the CEUS,or shows homogeneous hypo-enhancement in some areas. ③Tissues around the pipe-shaped echo usually appears that the homogeneous hypo-enhancing area and non-enhancing area exist together. ④Around the above-mentioned the hypo-enhancing area and non-enhancing area, a hyper-enhancing area can be seen, and appears to be a typical ring-shaped high-level echo in short-axis section of the pipe-shaped echo. ConclusionsConventional ultrasound can easily shows the distribution of craniocerebral gunshot injured areas characterized by pipe-shaped high-level echo, and CEUS can precisely demonstrate necrotic tissues in the gunshot injured areas,distinguish them from the degenerative tissues and normal tissues. The application of ultrasound technology will greatly improve the therapeutic and treatmental level of the craniocerebral gunshot wound.

Objective To explore the inheritance characteristics of SCN1A gene in familial severe myoclome epilepsy in infancy.Methods The clinical information and blood of the patients and their relatives who had febrile seizure(FS)or epilepsy history were collected.Blood genome DNA were extracted.All exons of SeN1A gene were PCR amplified and screened with denaturing high Performance liquid chromatography(DHPLC)technology,and sequence analysis was performed.Results Fourteen SME patients had FS or epilepsy family history.Five were found positive history in first class relatives and 2 of them had inherited mutations of SCN1A(C.4284+2T>C and e.1216G>T):Other9 were found positive history in second class relatives and 2 of them had de novo mutations of SCN1A.Condusions SCN1A is the pathogenic gene for SME.The same muatation of SCN1A gene can be related to different clinical phenotypes.SME patients whose first class relatives with FS or epilepsy history should be taken as the focus of SCN1A inherited mutation screening.

Objective To establish a molecular inversion probe ( MIP) method for detection of single base drug-resistance mutation in Hepatitis B virus ( HBV) gene.Methods The HBV wild type and YVDD mutant strain were isolated by Daping Hospital of the Third Military Medical University.The MIP was designed and applied to detect the HBV drug-resistance YVDD mutation in one case of wild type and one case of YVDD mutant HBV strain isolated previously.The results of MIP method were compared with that of sequencing to evaluate the detection accuracy.Results Thermal cycling single-base extension and connection reaction performed by Taq DNA Ligase and Ampligase DNA Ligase could ensure the specificity of the detection.The optimum probe concentration of MIP was 1 nmol/L.Through detection of the target gene with different DNA concentrations , the detection sensitivity of MIP was determined as 1 nmol/L.The results of MIP were consistent with that of sequencing method in detection of the clinical samples.Conclusion MIP is successfully used to detect single-base drug-resistance mutation in HBV gene.

Objective To establish the mathematical models of stature estimation for Sichuan Han female with measurement of lumbar vertebrae by X-ray to provide essential data for forensic anthropology re-search. Methods The samples, 206 Sichuan Han females, were divided into three groups including group A, B and C according to the ages. Group A(206 samples) consisted of all ages, group B(116 samples) were 20-45 years old and 90 samples over 45 years old were group C. All the samples were examined lumbar vertebrae through C Rtechnology, including the parameters of five centrums (L1-L5) as anterior border, posterior border and central heights (x1-x15), total central height of lumbar spine (x16), and the real height of every sample.The linear regression analysis was produced using the parameters to establish the mathematical models of stature estimation. Sixty-two trained subjects were tested to verify the accuracy of the mathematical models. Results The established mathematical models by hypothesis test of linear regression equation model were statistically significant (P<0.05).The standard errors of the equation were 2.982-5.004 cm, while correlation coefficients were 0.370-0.779 and multiple correlation coefficients were 0.533-0.834.The return tests of the highest correlation coefficient and multiple correlation coefficient of each group showed that the highest accuracy of the multiple regression equation, y=100.33+1.489 x3-0.548 x6+0.772 x9+0.058 x12+0.645 x15, in group Awere 80.6% (±1SE ) and 100% (±2SE ). Conclusion The established mathematical models in this study could be applied for the stature estimation for Sichuan Han females.

Objective:To retrospectively assess the relationship between immune disorder and acute gastrointestinal injury (AGI) in patients after severe polytrauma.Methods:Totally 205 patients with severe polytrauma admitted to Tongji Hospital from April 2018 to October 2019 were enrolled as the observation group, and 23 healthy volunteers were served as the control group. According to the diagnostic criteria of AGI, all patients were divided into the AGI group (with AGI) or N-AGI group (without AGI), AGI patients were divided into the S-AGI group or L-AGI group according to the severity. The levels of cytokines and lymphocyte subset were evaluated at day 1, 7, and 14 after severe polytrauma. The differences between groups were statistically analyzed. The independent risk factors of AGI were analyzed by Logistic regression analyzed.Results:Totally 79.5% (163/205) of patients with severe polytrauma were accompanied by AGI. There were significant differences in the ratio of Tc, Th at day 1 after trauma, the levels of IL-6, TNF-α, IL-8, IL-10, the ratio of Ts, Th/Ts, Treg at day 7 after trauma, and the levels of IL-8, IL-10,the ratio of Ts, Th/Ts, Treg at day 14 after trauma between the AGI group and N-AGI group ( P<0.05). There were significant differences in the ratio of Tc, Th, the levels of IL-6, TNF-α at day 1 after trauma and the ratio of Ts, Th/Ts, Treg, the levels of IL-8, IL-10 at day 7 and 14 after trauma between the S-AGI group and L-AGI group ( P<0.05). Logistic regression analysis showed that Ts 7 d ( OR=2.018, 95% CI: 1.105-5.364, P=0.013), Treg 14 d ( OR=3.612, 95% CI: 1.375-8.476, P=0.006), IL-6 7 d ( OR=1.824, 95% CI: 1.011-5.835, P=0.024), IL-10 14 d ( OR=2.847, 95% CI: 1.241-6.216, P=0.014), TNF-α 7 d ( OR=1.754, 95% CI: 1.215-5.441, P=0.018) were independent risk factors in patients with AGI after severe polytrauma. Conclusions:AGI is more easily occurred in patients with the heavier immune disorders after severe polytrauma. AGI can also aggravate pre-existing immune disorders in patients after severe polytrauma.

Objectire:To explore and evaluate the predictors for the prognosis of acute besilar artery occlusion(BAO)and the clinical efficacy of intra-arterial thrombolysis and stenting for BAO.Methods:Intra-arterial thrombolysis was administered with recombinant tissue plasminogen activator or urokinase in 52 patients with BAO within 3 to 48 hours.Stenting was performed in patients whose partial recanalization of residual stenosis＞50%after the thrombolysis.National Institutes of Health Stroke Scale(NIHSS)score was measured before the procedure,and the modifled Rankin scale(mRS)score was obtained at 3 months after the procedure.The clinical data were evaluated with the multivariable stepwise logistic regression analysis and Fisher's exact test.Results:Complete recanalization achieved in 24 patients(46.2%),partial recanalization in 16 patients(30.7%),and non-recanalization in 12 patients(23.1%).mRS scores:22 patients(42.3%)had a favorable outcome,32 survived(61.5%),and 20 died (38.5%).The prognosis of BAO was significantly correlated with the NIHSS score(P＜0.01),therapeutic time window (P ＜0.05) and recanalization level (after the thrombolysis and stenting)(P＜0.01 );the good recanalization after the intra-arterial thrombolysis was significantly correlated with the NIHSS score (P ＜0.01) and therapeutic time window (P ＜0.05).Multivariate analysis showed that the NIHSS score ＜ 14 (P ＜ 0.01 ) and good recanalization could independently predict the favorable prognosis of BAO.Conclusions:The NIHSS score ＜ 14 and good recanalization were the independent predictors for good prognosis of BAO.The rapid and timely treatment of BAO with intra-arterial thrombolysis and stenting is a safe and effective measure.