ABSTRACT
Objective To develop mathematical models for skeletal age determination with multiple statistic method based on the correlation between age and the growth of the epiphysis of extremitas sternalis of clavicle in Shanxi adolescents. Methods The 562 Shanxi sternoclavicular joint samples （454 cases of modelling, 108 cases of external verification） were scanned by the thin-section computed tomography. After volume rendering was obtained, indicators such as area of epiphysis, area of metaphysis, longest diameter of epiphysis and longest diameter of metaphysis of both extremitas sternalis of clavicle were collected. Indicators such as the ratio of area of epiphysis to area of metaphysis, and the ratio of longest diameter of epiphysis to longest diameter of metaphysis of both sides were calculated. Then multiple linear regression and random forest discriminant models were used to build mathematical models for age determination of adolescents. Results The obtained indicators exhibited a strong correlation with age （r>0.85）. The multiple linear regression model for males and females （all 4 indicators entering the model） based on the ratio of longest diameter of epiphysis to longest diameter of metaphysis and the ratio of area of epiphysis to area of metaphysis had an internal validation accuracy rate （±1.0 year） of over 92% and 108 cases had an external validation accuracy rate of over 70% （±1.0 year）. The out of bag error rates of random forest discriminant models were less than 2% for people over 18.0 years old （≥18.0 years old） and under 18.0 years old. The external validation accuracy rates of the 108 cases were over 80%. Conclusion The regression and discriminant models established in this study have certain reliability and accuracy and can be used in age determination of Shanxi adolescents.
Subject(s)
Adolescent , Female , Humans , Male , Age Determination by Skeleton , Clavicle/diagnostic imaging , Epiphyses/diagnostic imaging , Forensic Anthropology , Models, Theoretical , Osteogenesis , Reproducibility of ResultsABSTRACT
Objective?To investigate the effects of laparoscope assisted total gastrectomy (LATG) and open total gastrectomy (OTG) combined with D2 dissection in the treatment of upper gastric cancer and the impact on stress response.?Methods?145 patients with upper gastric cancer who underwent total gastrectomy from June 2014 to June 2017 were selected as research subjects, and they were divided into study group (treated by LATG, n = 70) and control group (treated by OTG + D2 dissection, n = 75) according to different surgical methods. The general condition of surgery, stress indexes cortisol (Cor), C reactive protein (CRP), postoperative recovery and the incidence of complications were compared between the two groups.?Results?The surgical time of the study group was longer than that of the control group, while the length of incision, intraoperative blood loss and length of hospital stay were shorter/less than those of the control group (P < 0.05). There was no significant difference in the number of dissected lymph nodes between the two groups (P > 0.05). Serum Cor and CRP levels in the study group were lower than those the control group during surgery and at 3 d after surgery (P < 0.05). The initial exhaust time and recovery time of liquid diet in the study group was shorter than that in the control group (P < 0.05), but there was no significant difference between the two groups in the rate of second surgery and readmission rate within 30 days (P > 0.05). The incidence of complications in the study group at 6 months after surgery was lower than that in the control group (P < 0.05).?Conclusion?Compared with OTG and D2 dissection, LATG has advantages of less trauma, earlier exhaust and feeding and fewer stress reactions, with quick recovery and few complications.
ABSTRACT
<p><b>OBJECTIVE</b>To establish a real-time quantitative PCR method for detecting the levels of the signal joint T cell receptor excision circles (sjTRECs) in murine thymocytes and spleen lymphocytes for determining the amount of naive T cells and evaluating the thymic function.</p><p><b>METHODS</b>The genomic DNA was extracted from murine thymocytes and splenocytes for PCR amplification of the target fragments. After purification of the PCR product, the recombination-activating gene 2 (RAG(2)) fragment was cloned into pGEMT-Easy vector to construct the standard plasmid. After PCR optimization, the standard curve was obtained and the samples (thymocytes and splenocytes of BALB/c and C(57)BL/6 mice) were detected for sjTRECs by real-time quantitative PCR.</p><p><b>RESULTS</b>The standard plasmid was correctly constructed, and the standard curve with high reliability was obtained. No statistical difference was observed in sjTREC contents in the T lymphocytes between the two mouse strains.</p><p><b>CONCLUSIONS</b>Real-time quantitative PCR for sjTREC analysis is established successfully, which offers an important means for thymic function analysis and a reliable model establishment for study the thymus.</p>