Ectopic thyroid (ETG) is a thyroid tissue located outside the normal anatomical position, often occurring in the chest. Clinical symptoms are related to its location and its impact on adjacent structures. In ETG imaging examination, single photon emission computed tomography (SPECT) nuclide imaging of thyroid perchlorate ( 99Tc mO 4-) is the most commonly used method for localization and characterization. ETG with normal function shows high radiation uptake in the corresponding area. For difficult to distinguish tumors in the base of the tongue and the thyrohyoid region, 131I or 123I imaging with more specificity for thyroid tissue uptake is needed. ETG exhibits a variety of manifestations in computed tomography (CT) and magnetic resonance imaging (MRI), mostly irregular soft tissue density masses with clear boundaries and uneven density. There are low-density cystic changes or high-density calcifications within the masses, with uneven or uniform enhancement. In ultrasound, ETG is mainly hypoechoic, with some showing cystic solid echoes and abundant blood flow signals within the gland. Asymptomatic ETG patients usually do not require treatment, while symptomatic patients often require surgical resection and have a good prognosis. Before surgery, relevant examinations should be combined to clarify the nature of the tumor as much as possible, to avoid permanent hypothyroidism caused by misdiagnosis and misresection.

pancreatic cancer is a common malignant tumor of digestive system, with poor prognosis. About 80% of patients have lost the opportunity of surgical resection when diagnosed. In different treatment schemes, radioactive seed 125I implantation can improve the quality of life of patients with unresectable pancreatic cancer and is expected to improve their survival rate. This article reviews the clinical applications of 125I particle implantation therapy combined with chemotherapy, cryotherapy, intracavitary irradiation, stent placement, radiofrequency ablation, nanoknife, and bypass surgery, in order to better promote its clinical application. However, it is necessary to establish unified dosage standards and regulatory guidelines to make them safer and more widely serve clinical practice.

Objective To investigate the characteristics of CT findings in pediatric ovarian torsion and improve the understanding of pediatric ovarian torsion.Methods The clinical and CT data of 20 cases of ovarian torsion confirmed by pathology and/or surgery were analyzed retrospectively,based on the timing of ovarian torsion,they were divided into fetal and non-fetal groups.All 20 cases underwent plain CT scan and 11 cases underwent CT enhancement.Results All of the 20 cases were unilateral duplication,including 12 cases right and 8 cases left.There were 8 cases of ovarian torsion in the fetal group,all of them were visited with the finding of abdominal mass.The eggshell calcification on CT manifestations was found in 8 cases,and 2 cases of pelvic effusion.There were 12 cases of ovarian torsion in the non-fetal group,all of them presented with abdominal pain,CT showed the disc sign in 7 cases,peduncular protrusion sign in 6 cases,adnexal bleeding sign in 2 cases,subcapsular effusion sign in 2 cases,the uterus displaced to the ipsilateral ovary in 6 cases and pelvic effusion in 10 cases.The disc sign and peduncular protrusion sign were direct signs for the diagnosis of ovarian torsion,and the adnexal bleeding sign and subcapsular effusion sign suggested the possibility of necrosis.Conclusion Pediatric ovarian torsion CT findings with typical signs such as disc sign,peduncular protrusion sign,adnexal bleeding sign and subcapsular effusion sign,combined with clinical history,a more accurate diagnosis can be given,providing assistance in clinical treatment.

Follicular lymphoma (FL) is the most common inert B-cell lymphoproliferative disease characterized by extensive lymph node involvement, splenomegaly, and bone marrow infiltration. In recent years, with the development of molecular imaging technology and precision medicine, the imaging research of FL has been moving towards a more refined direction. 18F-FDG PET/CT plays an increasingly important role in the diagnosis, staging, efficacy evaluation, and prognosis judgment of FL patients, promoting more precise personalized treatment and improving the efficacy and survival of FL patients. This article reviews the research progress of 18F-FDG PET/CT in the diagnosis and prognosis of FL based on domestic and foreign research progress, summarizing existing literature, in order to provide reference for personalized diagnosis and treatment of FL.

The emergence of high virulent mutant strains of infectious bursal disease virus(IBDV)becomes a serious threat to the poultry industry.However,the live attenuated IBDV vaccine can potentially revert to a virulent strain.Therefore,it is a necessary to develop safe and effective IB-DV-associated vaccines.The construction of a recombinant Marek's disease(MD)vaccine strain,CVI988,expressing the IBDV VP2 protein,can protect against disease induced by both IBDV and Marek's disease virus(MDV).Here,the IBDV-VP2 gene was integrated into the UL55 locus of CVI988 by bacterial artificial chromosome(BAC)technique,resulting in the recombinant virus CVI988 BAC-VP2.The recombinant virus was characterized by PCR,IFA and subsequently the bi-ological properties of the recombinant virus were investigated.The results showed that the recom-binant virus CVI988 BAC-VP2 was successfully rescued.The VP2 protein stably expressed in chick-en embryo fibroblasts(CEF).The growth kinetics and plague size assays showed that there was comparable replication ability between recombinant virus and parental virus.This study provides the basis for the development of a low-cost vaccine against both IBDV and MDV infections.

Objective To summarize and analyze the clinical features and etiologies in hospitalized patients with syndrome of inappropriate antidiuretics (SIAD) during the past 25 years.Methods All data of 128 patients with SIAD admitted to Chinese PLA General Hospital since January 1991 to January 2016 were collected.SIAD was diagnosed based on the 1957 criterion.Results (1) The most frequent causes of increased inappropriate secretion of vasopressin were malignant tumors , lung diseases ( e.g.pneumonia ) , and central nervous system diseases , in which malignant tumors accounted for 38.28% of the SIAD.(2) During the past 25 years, the proportion of malignant diseases declined from 4/7 to 35.29%, while, the proportion of pulmonary infection increased from 1/7 to 35.29% ( P<0.05 ) .( 3 ) The patients with malignant tumors had the lowest serum sodium and serum osmolality among all SIAD patients .(4) CT scan had a high diagnostic value for chest and brain detection .( 5 ) Among three SIAD subjects with unknown reasons at onset , two were diagnosed with small cell lung cancer and one with gastric cancer during follow -up.Conclusion The etiology of SIAD is complex and it could be attributed to multifarious etiological factors.Malignant tumors account for the largest proportion of all patients , and pulmonary infection was ranked in second place .Cautions on tumors have to be taken when serum sodium of a SIAD patient is below 118.1 mmol/L.