Whole-body PET/CT scanning is accompanied by substantial radiation dose in clinic. A large proportion of the radiation dose for examination obtained from whole-boby PET/CT is from CT scan. So how to control radiation dose without impairing CT image quality determined by the clinic is particularly important. Anthropomorphic phantom is the best choice for the study of radiation dose and image quality in PET/CT. The article reviews the meaning of anthropomorphic phantom and the study about PET/CT image quality and radiation dose with the phantom, Then analyzes the relationship between image quality of CT in PET/CT and radiation dose in the practical application.

Objective To explore the effect of ginseng co?enzyme Q10 suncream on the skin damage caused by ul?traviolet ( UV) radiation in mice. Methods 36 mice were randomly assigned to four groups. The mice were shaved on the back and the left untreated side was taken as control group, or was treated with UV as model group. Before treated with UV, the mice were painted with suncream containing ginseng co?enzyme Q10 , or octyl methoxycinnamate as positive con?trols. The mice were treated for 8 weeks. At the end of the experiment, blood samples of all mice were collected from the eyes, then subjected to cell counting or biochemical measurements, and skin samples were cut for pathological examina?tion. Results Compared with the control group, there was a significant increase in white blood cell counts ( P<0?05 ) and MDA content ( P<0?05 ) , and declined serum levels of SOD ( P <0?05 ) and GSH?Px ( P <0?05 ) in the model group, and the skin was rough and wrinkled with stratum corneum exfoliation. Compared with the model group, the mice of ginseng co?enzyme Q10 suncream group had significantly lower white blood cell count ( P<0?05 ) and MDA content ( P<0?05), and increased serum levels of T?SOD(P<0?05) and red blood cell counts (P<0?05). The skin had no rough? ness and wrinkles and without stratum corneum exfoliation. Compared with the model group, the positive control group showed significantly decreased white blood cell count (P<0?05) and MDA content (P<0?05), and increased serum lev?els of GSH?Px(P<0?05). The skin had no roughness and wrinkles and no stratum corneum exfoliation. However, there was no significant difference between the ginseng co?enzyme Q10 suncream group and positive control group. Conclusions Ginseng co?enzyme Q10 suncream shows satisfactory preventive effects on the UV radiation?induced skin damage in mice, similar to the preventive effects of the octyl methoxycinnamate?containing sunsream.

In colorectal cancer,the incidence of rectal cancer (RC) is relatively higher.Most of RC patients have chosen surgical treatment,while patient's own conditions,inadequate preoperative preparation,less surgical experiences of doctors,improper postoperative management and other factors lead to the appearance of anastomotic complications,such as anastomotic leakage,anastomotic stenosis and anastomotic bleeding.The risk of postoperative anastomotic complications is higher in low RC.However,it still has some controversies for the definition and classification of anastomotic complications,and the cause of complication is still not clear.The different treatment methods for anastomotic complications can be chosen,and most of them are effective.Since the anastomotic complications will affect the prognosis of patients,the prevention of complications is essential and some effective treatment methods should be used.

Objective To investigate the long-term efficacy of pure transanal total mesorectal excision (PtaTME) for middle-low rectal cancer.Methods The retrospective descriptive study was conducted.The clinicopathological data of 18 patients with middle-low rectal cancer who were admitted to the Sixth Affiliated Hospital of Sun Yat-sen University from July 2014 to August 2016 were collected.There were 7 males and 11 females,aged (58±13) years,with a range from 40 to 84 years.The body mass index was (22±3) kg/m2.All the 18 patients underwent PtaTME.Observation indicators:(1) surgical and postoperative conditions;(2) postoperative pathological examination;(3) follow-up and survival.Follow-up using inpatient reexamination,outpatient examination,and telephone interview were performed to detect anastomotic complications,anal function,urinary retention,sexual dysfunction,survival and tumor recurrence and metastasis once every 3 months within postoperative 6 months,once every 6 months from 6 months to 3 years,and once a year after 3 years up to June 2019.The measurement data with normal distribution were represented as Mean±SD,and the measurement data with skewed distribution were represented as M (range).Count data were expressed as percentages.Survival rates were calculated by the Kaplan-Meier method.Results (1) Surgical and postoperative conditions:18 patients successfully underwent PtaTME,without conversion to open surgery.The operation time,volume of intraoperative blood loss,distance between anastomosis and anal verge,time to first flatus,time to urinary catheter removal,and duration of postoperative hospital stay were (202±68) minutes,50 mL (range,20-400 mL),(4.5± 2.0)cm,2 days (range,2-7 days),3 days (range,2-5 days),and 7 days (range,5-10 days) in the 18 patients,respectively.There was no perioperative complication.Among 18 patients,4 underwent preventive ileostomy.(2) Postoperative pathological examinations:the length of surgical specimens,the number of lymph node dissection,distance from tumor to the distal margin were (11.0±3.0)cm,12±6,and 1.0 cm (range,0.8-3.7 cm),respectively.The 18 patients had complete mesorectal membrane excision,with negative proximal margin,distal margin,and circumferential margin.Tumor pathological staging:there were 2 cases in Tis stage,4 in T1 stage,7 in T2 stage,and 5 in T3 stage;16 in N0 stage,1 in N1 stage,and 1 in N2 stage.Tumor histological classification:2 patients had carcinoma in situ,9 had moderately differentiated adenocarcinoma,and 7 had high-differentiated adenocarcinoma.(3) Follow-up and survival:18 patients were followed up for 34.0-59.0 months,with a median follow-up time of 57.5 months.During the follow-up,4 patients developed grade B anastomotic leakage and were cured after conservative treatment.One patient developed anastomotic recurrence at 2 years after surgery,and no recurrence was found after surgical resection of the recurrent lesion.Four patients with prophylactic ileostomy had the stoma closured,and the anus function was satisfactory after surgery.There was no urinary retention or sexual dysfunction in the 18 patients.Of the 18 patients,17 had tumor free survival after surgery.The 3-year disease-free survival rate was 94.4％,and the 3-year overall survival rate was 100.0％ in 18 patients.Conclusion PtaTME can achieve high quality of specimen,which is safe and feasible for the treatment of rectal cancer.

Objective: To evaluate the feasibility and safety of transanal lateral lymph node dissection for mid-low rectal cancer. Methods: A descriptive case series research method was used. Clinical and pathological data of 5 mid-low rectal cancer patients who underwent transanal lateral lymph node dissection at Department of Colorectal Surgery, the Sixth Affiliated Hospital of Sun Yat-sen University from November 2018 to May 2019 were retrospectively collected and analyzed. Of 5 cases, 4 were male and 1 was female with mean age of (43.2±13.2) years and mean body mass index of (21.2±2.6) kg/m²; the mean diameter of tumor was (3.2±2.4) cm; the mean distance between tumor and anus was (6.3±2.5) cm; 3 received preoperative neoadjuvant chemotherapy. In preoperative TNM staging, 2 cases were T3N1M0, 1 was T3cN2aM0, 1 was T3cN2bM0, and 1 was T2N1M0. All the patients had no intestinal obstruction before operation. Surgical methods: (1) total mesorectal excision: using general transanal and transabdominal methods to mobilize and resect total mesorectum, and dissect No.252, No.253 lymph nodes; (2) transanal lateral lymph node dissection: dissect the adipose lymphoid tissue on the surface of the iliococcygeal muscle, the coccygeal muscle, and the obturator muscle (the No.283 lymph nodes) upward, and dissect No.263d and No.263p lymph nodes with fat tissue sequentially till the bifurcation of the internal and external iliac artery; (3) take out the specimen from anus, and make anastomosis between proximal colon and anal canal. Intraoperative and postoperative variables was observed. Results: All the 5 patients completed surgery successfully, and no patient needed to convert to open approach. The mean operative time was (295.6±97.7) minutes, and the median intraoperative blood loss was 70 (50-500) ml. The mean length of specimen was (12.9±3.0) cm, and the mean number of harvested lymph node was 30.4±9.9. The positive lateral lymph nodes were founder in 4 patients. The median distance between tumor and distal resection margin was 1.5 (1.2-8.0) cm. The resection margin in all the patients was negative. The mean time to postoperative flatus was (4.2±1.6) days, the mean postoperative spontaneous urination was (3.0±1.9) days, time to drainage tube removal was (5.6±1.9) days, and the mean postoperative hospital stay was (9.4±2.1) days. The postoperative TNM staging by pathology was 1 case with T1N0M0, 1 with T2N1M0, 1 with T3N2bM0, and 2 with T3N2M0. Five patients were moderately differentiated adenocarcinoma. Only 1 patient developed postoperative abdominal bleeding, who was healed after conservative treatment. The other 4 patients did not develop any perioperative complications, such as incision infection, presacral abscess, pelvic abscess, anastomotic leakage, or anastomotic stricture. Four patients underwent postoperative chemotherapy. All the patients were followed up for 2 to 28 weeks after surgery and they all felt well. The patients with stoma had fluent bowel. Conclusions Transanal lateral lymph node dissection is feasible and safe in the treatment of mid-low rectal cancer, which can achieve the purpose of extended radical resection of mid-low movement rectal cancer. Moreover, this procedure is a new method to treat rectal cancer patients with lateral lymph node metastasis.

This paper introduces the teaching method of medical-electrical cross-integration and the teaching practice experience in the past three years by taking the integration of medicine and electrical engineering as an example. Starting from the analysis of the characteristics of learning situation, the teaching introduction process, the case discussion and analysis, and the after-class tracking and improvement, this paper analyzes the characteristics of the medical-electrical cross-teaching and proposes the corresponding teaching methods and supporting cases. Preliminary exploration attempts show that this teaching method can improve students' comprehensive ability, especially multidisciplinary thinking ability, and has a certain positive effect.

Objective To observe the effect of compound Dihuang Granules on the expressions of DJ-1,IP3R,GRP75 and VDAC1 in liver and colonic tissue of Parkinson disease(PD)rats with yin deficiency and wind movement syndrome.Methods 6-Hydroxydopamine was used to inject into the right substantia nigra to prepare PD with yin deficiency and wind movement syndrome rats model.65 rats that successfully modeled were randomly divided into model group,madopar group(madopar 150 mg/kg)and TCM low-,medium-and high-dosage groups(compound Dihuang Granules 1.75,3.5,7 g/kg),with 13 rats in each group;another 13 rats without intervention were selected as the normal control group,and 13 rats were only injected with ascorbic acid solution as sham-operation group.The administration groups were given corresponding drugs by gavage,and the normal control group,sham-operation group and model group were given normal saline by gavage,once a day for 28 consecutive days.The neurobehavioral changes of rats were observed,and the morphology of liver tissue and colonic tissue were observed by HE staining,the protein and mRNA expressions of DJ-1,IP3R,GRP75 and VDAC1 in liver and colonic tissue were detected by immunohistochemical staining,Western blot and RT-PCR,respectively.Results Compared with the normal control group and the sham-operation group,the number of rotation circles of rats in the model group increased,with granular degeneration of liver tissue,loose cytoplasm of cells,slight hepatic steatosis,edema of colonic mucosal and submucosal layers,loose connective tissue,infiltration of a small number of lymphocytes,and significant vascular dilation,the expressions of DJ-1,IP3R,GRP75 and VDAC1 protein and mRNA in liver and colonic tissue were significantly decreased(P<0.01).Compared with the model group,the number of rotation circles of rats in madopar group and TCM groups were significantly decreased,with mild granular degeneration of liver cells,loose cytoplasm,orderly arrangement of hepatic cords,mild edema of the colon,a small amount of lymphocyte and granulocyte infiltration,and a small amount of vascular dilation,the protein and mRNA expressions of DJ-1,IP3R,GRP75 and VDAC1 in liver and colonic tissue significantly increased(P<0.05).The TCM high-dosage group showing the most obvious changes,there was no statistical significance with the madopar group(P>0.05).Conclusion Compound Dihuang Granules may restore endoplasmic reticulum-mitochondria homeostasis,improve gut-liver-brain axis mitochondrial function,protect dopamine neurons,and delay PD by regulating the expressions of DJ-1,IP3R,GRP75 and VDAC1 in liver tissue and colonic tissue.

Objective To explore whether Rho kinase inhibitor protects endotoxemia mice from kidney injury,and to investigate the mechanism underlying this effect. Methods Adult male C57BL/6 mice were randomly divided into three groups (n = 8 for each group): control,lipopolysaccharide (LPS),and LPS+ Y-27632 (Rho kinase inhibitor). For induction of acute kidney injury,mice were administered 30 mg/kg LPS intraperitoneally. Y-27632 (10 mg/kg body weight) was injected intraperitoneally 18 h and 1 h before injection of LPS,and an equal volume of sterile saline was administered at the corresponding time point in each group. The mice were killed 8 h after LPS administration. Blood samples and kidney tissues were taken and preserved for subsequent analysis. Results Pretreatment with Y-27632 significantly attenuated LPS-induced kidney injury;pretreatment with Y-27632 markedly reduced renal expression of inflammatory cytokines (TNF-α and IL-1β) in endotoxemia mouse,and also significantly inhibited LPS-induced caspase-3 expression in the kidney; and Y-27632 pretreatment dramatically reduced TLR4 protein expression and NF-κBp65 phosphorylation in kidney tissues of endotoxemia mouse. Conclusion Rho kinase inhibitor may inhibit TLR4 and NF-κB signaling pathway to reduce the inflammatory response in the kidneys of endotoxemia mice and alleviate acute renal injury induced by LPS.

Objective Based on the comparison and analysis of Raman spectra of liver meridian(including other meridian)and non-liver meridian(other meridian excluding liver meridian)traditional Chinese medicine,the accurate quantitative characterization data of liver meridian was obtained,and the liver meridian identification model was established and analyzed.Methods Taking 120 non-liver meridian(other meridian excluding liver meridian)traditional Chinese medicines(TCMs)as blank control and 120 liver-meridian(including other meridian)TCMs as experimental medicines,Raman spectra of 240 TCMs were obtained after sample pretreatment and Raman spectroscopy detection,and then quantified in units of 1 cm-1.Then combined with Random Forest(Random Forest,RF),Artificial Neural Network(Artificial Neural Network,ANN)and other algorithms,we constructed the identification models of quantized characterization of liver meridian.Results Compared with non-liver meridian(other meridian excluding liver meridian)TCMs,the Raman spectra of the liver meridian TCM were generally lower in the whole detection range,especially in the range of 200-1100 cm-1.The quantized Raman spectrogram data combined with ANN presented the best discrimination results with accuracy,precision>0.871,the receiver operating characteristic curve(ROC)was drawn and the area under ROC curve(AUC)was obtained,with AUC>0.921.Conclusion The Raman spectrogram of TCMs has significant correlation with liver meridian,which can be used as a whole quantized characterization of liver meridian.Combined with ANN,Raman spectrogram can carry out identification analysis efficiently and accurately,which is conducive to solving the bottleneck problem of lacking accurate data on medicinal properties and enriching the scientific connotation of attributing meridians.