Objective:To investigate the relationship between mandibular second molar calcification stage and cervical vertebrae maturity.Methods:Samples were derived from panoramic radiographs and lateral cephalograms of 500 subjects (223 males and 277 females)aged 9 to 18 years.Demirjian Index(DI)and cervical vertebrae maturation indicators(CVMI)were used for the evaluation of dental and skeletal maturity.Results:A significantly association was found between DI and CVMI(P <0.001).DI stage E was associated with CVMI Ⅱ(pre-peak of pubertal growth spurt).DI stages F and G was associated with CVMI Ⅲ and Ⅳ(peak of pu-bertal growth spurt).DI stage H was associated with CVMI Ⅴ and Ⅵ(end of pubertal growth spurt).Conclusion:DI and CVMI are significantly associated.Mandibular second molar DI stage is a reliable indicator of skeletal maturity.

Objective To investigate the polymorphism of human cytomegalovius UL143 gene of low passage clinical isolates in Guangzhou,China.Method PCR was performed to amplify the entire HCMV ULl43 gene region of 3 clinical isolates,which had been proven by multiplex PCR.The amplification products were cloned into pMD18-T-Vector and subjected to sequencing.The result of DNA sequences were analyzed together with the one of published homologous sequences in GenBank from 14 clinical isolates.Result There were several stop codons in UL143 gene due to a base deletion in open reading frame (ORF) of D3 isolate,which could lead to produce non-functional protein.UL143 ORF of Toledo isolate consisted of 279 nueleotides,encoding a protein with 92 amino acids.UL143 ORFs of other isolates consisted of 252 nueleotides,encoding a protein with 83 amino acids.The DNA sequences were quite conserved and all the variations were base substitution.The amino acid sequences of different isolates were highly conserved.with variation of 1.2%-2.4%.There were no additional or deleted sites of post translational modification of UL143 protein in all clinical isolates except Toledo isolate.There were some differences in the secondary structure among different isolates.The isoelectric point of UL143 protein of all clinical isolates except Toledo isolate was 8.75.Conclusion All DNA and deduced amino acid sequences of UL143 gene shared great similarity among HCMV clinical strains regardless of their polymorphism.

From April 2017 to April 2018, three male patients aged 46-71 years with large area burns were treated in our hospital. Acute acalculous cholecystitis (AAC) symptoms of the patients began to appear 15-81 days after injury. AAC was diagnosed 24-81 days after injury. Ultrasound-guided percutaneous transhepatic cholecystostomy was performed 26-82 days after injury. The symptoms subsided in 2 patients, and cholecystectomy was performed in 1 patient with gallbladder perforation 94 days after injury. The patients were cured and discharged 41-118 days after injury. No recurrence of cholecystitis occurred during 8-9 months of follow-up after discharge.

A single infusion of ketamine has sustained antidepressant effects and significantly de-creases the risk of suicide,and the effects can last up for 7-10 days,but the underlying mechanism is un-clear. The mechanism was reviewed underlying the antidepressant effects of ketamine,and found that ket-amine may exert its antidepressant effect by regulating sleep/wake cycle,synaptic pruning,molecular path-ways,and neural circuits for treatment-refractory depression. Further studies are needed to investigate the ge-netic,molecular mechanisms underlying the sustained antidepressant effect of ketamine,and the associated imaging findings through in vivo imaging of animals and imaging genetics techniques,explore the optimal time for administration of ketamine,and then provide accurate scientific basis for enhancing its anti-depressant effect.

This study introduced a time-delay exposure system independent of the mobile digital radiography equipment. The system consisted of lithium battery, delay control circuit, micro electric motor and related auxiliary facilities. When the starting time was reached through the delay circuit, the motor pushed out the rod to squeeze the exposure button and completed the exposure. The accessories used in this system were easy to purchase and cheap. At the same time, the technology was mature and had good compatibility. The exposure success rate was high and the exposure effect was satisfactory. This time-delay exposure system had good practicability and popularization value.
Radiographic Image Enhancement ; Technology ; Electric Power Supplies

With the increasing proportion of human papilloma virus(HPV)infection in the pathogenic factors of oro-pharyngeal cancer,a series of changes have occurred in the surgical treatment.While the treatment mode has been im-proved,there are still many problems,including the inconsistency between diagnosis and treatment modes,the lack of popularization of reconstruction technology,the imperfect post-treatment rehabilitation system,and the lack of effective preventive measures.Especially in terms of treatment mode for early oropharyngeal cancer,there is no unified conclu-sion whether it is surgery alone or radiotherapy alone,and whether robotic minimally invasive surgery has better func-tional protection than radiotherapy.For advanced oropharyngeal cancer,there is greater controversy over the treatment mode.It is still unclear whether to adopt a non-surgical treatment mode of synchronous chemoradiotherapy or induction chemotherapy combined with synchronous chemoradiotherapy,or a treatment mode of surgery combined with postopera-tive chemoradiotherapy.In order to standardize the surgical treatment of oropharyngeal cancer in China and clarify the indications for surgical treatment of oropharyngeal cancer,this expert consensus,based on the characteristics and treat-ment status of oropharyngeal cancer in China and combined with the international latest theories and practices,forms consensus opinions in multiple aspects of preoperative evaluation,surgical indication determination,primary tumor re-section,neck lymph node dissection,postoperative defect repair,postoperative complication management prognosis and follow-up of oropharyngeal cancer patients.The key points include:① Before the treatment of oropharyngeal cancer,the expression of P16 protein should be detected to clarify HPV status;② Perform enhanced magnetic resonance imaging of the maxillofacial region before surgery to evaluate the invasion of oropharyngeal cancer and guide precise surgical resec-tion of oropharyngeal cancer.Evaluating mouth opening and airway status is crucial for surgical approach decisions and postoperative risk prediction;③ For oropharyngeal cancer patients who have to undergo major surgery and cannot eat for one to two months,it is recommended to undergo percutaneous endoscopic gastrostomy before surgery to effectively improve their nutritional intake during treatment;④ Early-stage oropharyngeal cancer patients may opt for either sur-gery alone or radiation therapy alone.For intermediate and advanced stages,HPV-related oropharyngeal cancer general-ly prioritizes radiation therapy,with concurrent chemotherapy considered based on tumor staging.Surgical treatment is recommended as the first choice for HPV unrelated oropharyngeal squamous cell carcinoma(including primary and re-current)and recurrent HPV related oropharyngeal squamous cell carcinoma after radiotherapy and chemotherapy;⑤ For primary exogenous T1-2 oropharyngeal cancer,direct surgery through the oral approach or da Vinci robotic sur-gery is preferred.For T3-4 patients with advanced oropharyngeal cancer,it is recommended to use temporary mandibu-lectomy approach and lateral pharyngotomy approach for surgery as appropriate;⑥ For cT1-2N0 oropharyngeal cancer patients with tumor invasion depth＞3 mm and cT3-4N0 HPV unrelated oropharyngeal cancer patients,selective neck dissection of levels ⅠB to Ⅳ is recommended.For cN+HPV unrelated oropharyngeal cancer patients,therapeutic neck dissection in regions Ⅰ-Ⅴ is advised;⑦ If PET-CT scan at 12 or more weeks after completion of radiation shows intense FDG uptake in any node,or imaging suggests continuous enlargement of lymph nodes,the patient should undergo neck dissection;⑧ For patients with suspected extracapsular invasion preoperatively,lymph node dissection should include removal of surrounding muscle and adipose connective tissue;⑨ The reconstruction of oropharyngeal cancer defects should follow the principle of reconstruction steps,with priority given to adjacent flaps,followed by distal pedicled flaps,and finally free flaps.The anterolateral thigh flap with abundant tissue can be used as the preferred flap for large-scale postoperative defects.