Objective To study the development of children's understanding the probabilities of the causes of illness.Methods 120 5-to 9-year-old children were interviewed via open-ended items and forced choices about illness. Results There were statistical significance in their understanding of the probabilities of the causes of illness and their strategies of prediction among the three groups(χ2(2)= 50.134,P ＜0.01;χ2(6)= 95.781, P ＜0.01);in addition, there was statistical significance between the two educational backgrounds (χ2(1)= 11.162, P ＜0.01;χ2(3)= 35.043, P ＜0.01). Conclusion Some preschool-aged children viewed outcomes of familiar causes of illness as probabilistic. The children's understanding of the causes' probabilities appeared to be based on naive biology. 5- to 9-year-old children made probabilistic predictions from a single cause to multiple causes. Children coming from higher educational backgrounds outperformed their counterparts coming from lower educational backgrounds with respect to understanding illness.

The operating principle of data acquisition section of TOSHIBA Aquilion 16 is introduced.The operating principles of the main detector,the reference detector,the data acquisition section and its power supply are analyzed.The troubleshooting methods for DAS are put forward.

Objective To evaluate our self-designed guide used clinically in percutaneous placement of lumbosacral pedicle screws in surgery of lumbar vertebral fractures.Methods From May 2012 to March 2015,143 patients with lumbar vertebral fracture were treated with reduction and fixation using percutaneous lumbosacral pedicle screws in our department.Percutaneous placement of lumbosacral pedicle screws was assisted by our self-designed guide in 69 of them(guide group) but not in the other 74 cases (manual group).The 2 groups were compatible in preoperative general data (P ＞ 0.05).The 2 groups were compared in terms of localization time for a single screw,puncture accuracy,times of intraoperative fluoroscopy,operation time,intraoperative blood loss,and hospital stay.Results The guide group had significantly better localization time for a single screw,puncture accuracy,times of fluoroscopy and operation time than the manual group (P ＜ 0.05),but the 2 groups showed no significant differences in intraoperative blood loss and hospital stay (P ＞ 0.05).The guide group obtained an average follow-up of 12.9 months (from 12 to 16 months) while the manual group obtained an average follow-up of 13.2 months (from 12 to 18 months).All fractures healed primarily,without complications like injuries to nerve root or dural sac.Conclusion Our self-designed guide is recommendable because it can obviously improve accuracy of placement of lumbosacral pedicle screws,shorten operation time,and decrease times of intraoperative fluoroscopy.

A method was developed for analyzing the stable carbon isotope ratio of five volatile components ( Ethanol, Glycerol, Acetic acid, Ethyl lactate, 2-methyl-butanol ) in wine using gas chromatography-combustion-isotope ratio mass spectrometer ( GC-C-IRMS ) . The sample injection volume was less than 0. 5 μL, and the analytical time of each run was less than 14 min. The precision of this method was 0. 08‰-0. 25‰ for analyzing standards, while 0. 09‰-0. 36‰ for wine samples. Compared to element analysis-isotope ratio mass spectrometry ( EA-IRMS) results, the deviations were lower than 0. 5‰. Fifty-four wine samples from France, Australia, America and China were considered. The δ13 C of five volatile components were measured using GC-C-IRMS. Discriminant analysis ( DA) was employed for analyzing the geographical origin traceability of selected wine. The result indicated that δ13 C of volatile components could be used to distinguish the origin of wines. The method was shown to be effective in improving detection of the origin traceability of wine.

Gelatin and hydroxyapatite were introduced to polyvinyl alcohol (PVA) hydrogel with an attempt to enhance the performances of PVA hydrogel. Through a reiterative freezing-thawing methods, three kinds of PVA composite hydrogels were prepared. The mechanical performances of these composite hydrogels with the same PVA and HA content but varying gelatin content, such as tensile strength, elasticity modulus, creep curve, relaxation curve and friction coefficient were evaluated by using a computer-controlled universal electronic mechanical testing machine and a UMT-II frictional testing machine. The additional effects of hydroxylapatite and varying gelatin on the performances of composite PVA hydro-gels were analyzed. It was found that the gelatin content directly influenced the physical performances of PVA composite hydrogels; but no linear relationship was recorded. PVA composite hydrogel containing 2wt-% gelatin gave optimal results, i.e. tensile strength of 5.5MPa, compressive elastical modulus of 1.48MPa, creeping rate of 31% in 45 minutes, stress relaxing rate of 40.3%, and the starting friction coefficient of 0.332.
Elastic Modulus ; Friction ; Hydrogels ; chemical synthesis ; chemistry ; Mechanical Phenomena ; Polyvinyl Alcohol ; chemical synthesis ; chemistry ; Tensile Strength

OBJECTIVETo study the management for the perineal incision after laparoscopic-assisted abdominoperineal resection for rectal cancer.

METHODSClinical data of 87 patients undergoing laparoscopic Miles operation for lower rectal cancer from June 2009 to February 2014 were collected and studied. Presacral space drainage group: presacral space drainage tube was applied in 42 patients. Combined drainage group: presacral space drainage tube combined with subcutaneous vacuum pressure suction was applied in 45 cases. In combined drainage group, except the presacral drainage tube, another drainage tube was placed subcutaneously and connected to a negative pressure ball, which was fixed on the lateral anterior of perineal wound by the further incision and drainage. After subcutaneous tube was placed for 2 weeks, as drainage fluid was limpid and <15 ml/d for 3 days, meanwhile no obvious pelvic fluid was detected by ultrasound, and the wound healed quite well without redness and edema, then the subcutaneous tube with the negative pressure ball could be removed.

RESULTSThere were 51 males and 36 females with the mean age of 26-78(56.9±10.8) years old. The laparoscopic Miles operation was successfully completed in all the cases without death and complications. The drainage tube was placed for 4-13(8.0±2.5) days in presacral space drainage group, and for 4-14(6.7±2.4) days in combined drainage group. The subcutaneous tube was placed for 14-24(15.8±3.0) days. The primary healing rate of perineal wound in presacral space drainage group and combined drainage group was 66.7%(28/42) and 91.1%(41/45) respectively, while the perineal wound infection rate was 21.4%(9/42) and 4.4%(2/45) respectively, whose differences between two groups were both significant (χ=7.911, P=0.005 and χ=5.674, P=0.017).

CONCLUSIONPresacral space drainage tube combined with subcutaneous vacuum pressure suction in laparoscopic-assisted abdominoperineal resection for rectal cancer has better efficacy and lower infection rate for perineal incision, which is worth wide application.

Objective:To explore the application value and initial clinical experience of fluorescence-enhanced laparoscopy combined with indocyanine green in radical cystectomy with pelvic lymphadenectomy.Methods:A retrospective analysis was performed on the clinical data of a total of 8 patients admitted from May 2018 to August 2019 who underwent laparoscopic radical cystectomy with pelvic lymphadenectomy for muscle-invasive bladder cancer using the fluorescent laparoscopy system.There were 6 males and 2 females; aged 58 to 71 years, with an average of 65.8 years. The preoperative pathology was urothelial carcinoma, with 2 cases in T 2a stage, 4 cases in T 2b stage, and 2 cases in T 3a stage. The patient was injected a total of 2 ml of 2.5 mg/ml of indocyanine green through a rigid cystoscope using a 18 gauge cystoscope injection needle before surgery. The PINPOINT endoscopic fluorescence camera system performed surgery in real-time. A systematic examination of the surgical area under near-infrared fluorescence was performed every 5 minutes. Observation and recording of indocyanine green combined with fluorescence laparoscopy to mark the bladder tumor area and identify the sentinel drainage. Results:Eight cases were successfully completed under the fluorescence laparoscopic system.In terms of tumor markers, cystoscopy with indocyanine green allowed 7 of the 8 patients to successfully identify the tumor area under fluorescent laparoscopy. Six of the 8 patients with sentinel lymph nodes identified by indocyanine green lymphangiography were also successful, of which 3 were positive for lymph nodes. At the same time, intravenous indocyanine green was used to observe that the blood supply to the bladder and the end of the ureter was good. The operation time was 190-310 minutes, with an average of 235 minutes; the bleeding volume was 150-380 ml, with an average of 180 ml; the postoperative hospital stay was 10-22 days, with an average of 14.5 days. Postoperative pathological staging 2 cases in T 2a stage, 3 cases in T 2b stage, 3 cases in T 3a stage, with total number of lymph nodes 8-14, average 10. The 8 cases were followed-up for 4-12 months, average 5.5 months, without indocyanine green related complications. Conclusions:Indocyanine green fluorescent laparoscopy can accurately locate and identify the bladder tumor area and pelvic lymph nodes during radical cystectomy, which can reduce positive margins and unnecessary enlarged lymph node dissection.

Objective: To isolate the cross-reactive antibodies against hemagglutinin of influenza virus and identify its biological function. Methods: The antibodies gene reservoir of cross-reactive and H5N1 pseudotype particles neutralizing B cell circulating in peripheral blood of a human H5N1 case was recovered by in vitro B cell culture, screening, RT-PCR and expression vector cloning techniques. The Ab gene pairing was screened by transient transfection of human kidney 293T cells and detected using ELISA and neutralization test. The heterosubtypic antibodies were prepared and characterized. Results: We discovered the VH1-2-based heterosubtypic antibodies from two B cell lineages could neutralize GX-H5N1 pseudotype particles and have broader binding with Group 1 (including H1, H5, H6 and H9) and H7 subtype. Conclusions Cross-reactive antibodies can be induced by H5N1 infection.

Objective:To investigate the efficacy and safety of cold snare polypectomy (CSP) and hot snare polypectomy (HSP) for the removal of colorectal polyps of 10-15 mm.Methods:A total of 173 polyps of 154 patients with at least one polyp of 10-15 mm were resected under colonoscopy from December 2019 to December 2020. Based on Paris classification, the polyps were divided into Ⅰsp, Ⅰs and Ⅱa. According to random number table, the polyps were randomly divided into CSP group ( n=85) and HSP group ( n=88). The polyp size, location, morphology, histological classification, complete resection rate, incidence of complications, resection time and the number of prophylactic clips were compared between the two groups. Results:There were no significant differences in age, sex, indication of colonoscopy or the success rate of intubation at the end of ileum between the two groups. The polyps of the two groups were comparable in size, position, morphology and histological classification. There were no significant differences in the complete resection rate of polyps, rates of intraoperative bleeding and postoperative bleeding or perforation between the CSP group and the HSP group. The operation time in CSP group was significantly shorter than that in HSP group (63.5 ±23.6 s VS 184.3 ±62.4 s, P<0.05). The number of prophylactic clips used in CSP group was significantly less than that in HSP group (0.8±0.5 VS 1.4±0.7, P<0.05). Conclusion:CSP shows similar complete resection rate and complication incidence, and requires shorter operation time and fewer prophylactic clips, compared with HSP, in the resection of colorectal sessile polyps of 10-15 mm.

Objective To explore the efficacy of unilateral biportal endoscopy(UBE)for lumbar intervertebral foramen stenosis combined with lumbar disc herniation through Sublamina approach.Methods From October 2021 to June 2022,7 elderly patients with typical symptoms of lumbar disc herniation in the intervertebral foramen area accompanied by spinal stenosis were retrospectively analyzed.There were 6 patients with lumbar disc herniation and nerve root canal stenosis at L4/5 and 1 patient at L5/S1.The mean course of disease was(8.6±2.5)months.All the patients were treated by UBE through Sublamina approach.Results Postoperative limb radicular symptoms of 7 patients were relieved.The visual analogue scale(VAS)of limb pain was significantly decreased from preoperative(8.6±1.3)to(2.1±1.1)at 2 d after the surgery(P<0.05),the Japanese Orthopaedic Association(JOA)score was significantly increased from preoperative(10.1±2.4)to(17.3±1.8)at 2 d after the surgery(P<0.05).Conclusion UBE for lumbar intervertebral foramen stenosis combined with lumbar disc herniation through Sublamina approach has a satisfactory therapeutic effect,providing a new idea for the surgical treatment of this disease.