Objective To investigate the effect of 100 kVp low tube voltage combined with adaptive statistical iterative reconstruc-tion-Veo(ASIR-V)on the imaging display,image quality and radiation dose of Adamkiewicz artery(AKA).Methods Ninety patients with computed tomography angiography(CTA)of aorta were randomly divided into two groups.In group A,the tube voltage was 100 kVp,and ASIR-V was 80%reconstructed.The tube voltage in group B was 120 kVp,and adaptive statistical iterative recon-struction(ASIR)was 40%reconstructed.The CT value and the standard deviation(SD)value of descending aorta were measured at the 12th thoracic vertebra level,and the CT value and the SD value of the spinal cord were measured at the same level to calculate the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of AKA.According to the continuity between AKA and intercostal artery or lumbar artery,the visualization of AKA was evaluated by two doctors with a double-blinded method and a five-point method,and the radiation doses of group A and group B were compared.Results Compared with group B,the CT value of aorta in group A was sig-nificantly increased by about 22.83%(P<0.001).The background noise of AKA in group A was significantly lower than that in group B(P<0.001),and the SNR and CNR were significantly higher than those in group B(P<0.001).The visualization score of AKA in group A was higher than that in group B(P<0.05).The effective dose(ED)in group A was significantly lower than that in group B by about 41.28%(P<0.001).Conclusion 100 kVp combined with ASIR-V technique for spinal cord AKA imaging can obtain better image quality,improve the sensitivity of AKA display and reduce the radiation dose.

BACKGROUND:At present,there is still controversy in clinical practice about the choice of internal fixation of Pauwels type Ⅲ femoral neck fracture,and the selection of internal fixation that provides stable fixation strength is the key basis for achieving Pauwels type Ⅲ fracture fixation. OBJECTIVE:The three-dimensional finite element analysis method was used to test the difference in biomechanical strength of three types of internal fixation in Pauwels type Ⅲ femoral neck fracture,which provided a reference for its clinical treatment. METHODS:Using the CT data of the left femur of a healthy male volunteer,a complete femur and its cancellous bone were reconstructed in Mimics software,and Geomagic studio software was used for reverse modeling.Cannulated compression screw,dynamic hip screw,and femoral neck system were created in UG-NX software.Three kinds of internal fixation models were assembled on the femur model,and Pauwels type Ⅲ femoral neck fracture was simulated by Hypermesh software.Finally,Abaqus software was used to carry out finite element experimental analysis to analyze and compare the stress distribution,stress peak,strain,and displacement distribution caused by fixed femoral neck fracture of different internal fixation systems. RESULTS AND CONCLUSION:(1)The stress of the proximal femur bone mass was mainly distributed in the area below the femoral neck near the fracture end,with the highest stress peak in the dynamic hip screw group and the smallest in the femoral neck system group.(2)The stress distribution of the internal fixation device was mainly concentrated on the screw surface near the fracture line,with the highest stress peak in the femoral neck system group and the smallest in the dynamic hip screw group.(3)The main strain field of the proximal femur bone mass was distributed in the upper surface area where the bone and screw contacted,and the yield strain was the smallest in the femoral neck system group and the largest in the cannulated compression screw group.(4)The main strain field of the internal fixation device model was distributed on the upper surface of the femoral neck screw,with the yield strain being the smallest in the femoral neck system group and the largest in the cannulated compression screw group.(5)The displacement distribution values of femur,proximal bone mass,distal bone block,internal fixation device and internal fixation with the femur as a whole in the three femoral neck fracture internal fixation models decreased gradually from proximal to distal,and the peak displacement of the femoral neck system group was the largest and the lowest in the dynamic hip screw group.(6)The results showed that when the Pauwels type Ⅲ femoral neck fracture was fixed,the stress distribution of femoral neck system was more uniform,the mechanical conduction characteristics were better,and it was subjected to lower yield strain,higher stress and higher displacement.It has relatively better biomechanical stability and can provide a superior mechanical environment for fracture healing.

Objective To construct and validate an effective prognostic nomogram for the patients with incidental gallbladder cancer(IGBC).Methods The clinical data of 161 patients with IGBC requiring radical surgery admitted to the First Affiliated Hospital of Xi'an Jiaotong University from May 2011 to October 2022 was analyzed retrospectively.COX proportional risk regression model was used to screen for influencing factors on overall survival(OS)of IGBC.Nomogram was constructed based on independent influencing factors that affected the prognosis of IGBC patients.The concordance index(C-index)and calibration curve were used to validate the performance of the model.Receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA)were used to validate the predictive accuracy and net benefit of the plotted column chart.Results Univariate COX regression analysis suggested that age,T stage,N stage,M stage,preoperative carcinoembryonic antigen(CEA),preoperative carbohydrate antigenl9-9(CA19-9),preoperative red blood cell volume distribution on width coefficient of variation(RDW-CV),treatment method,and recurrence and metastasis were risk factors which affected the long-term survival of IGBC patients after radical surgery.Multivariate COX regression analysis suggested that T stage,N stage,preoperative CA19-9,preoperative RDW-CV,preoperative AST,treatment methods,and recurrence and metastasis were independent risk factors which affected the prognosis of IGBC patients.The C-index of the constructed prognostic model was 0.872.The calibration plot demonstrated good performance of the Nomogram.ROC curve analysis showed an area under the curve of 0.869,confirming a high sensitivity and specificity.A high net benefit was proven by DCA.Conclusions The constructed Nomogram.can accurately and intuitively predict the survival probability of IGBC patients after radical surgery.

Pancreatic cancer has a very poor prognosis.Early diagnosis and treatment are especially critical for improving its prognosis.Nanotechnology has been widely used in the diagnosis and treatment of pancreatic cancer.Relying on the unique physicochemical properties of nanoparticles and their rich surface modifications,effective enrichment of tumor sites can be achieved.Magnetic iron oxide nanoparticles(MIONPs)is one of the commonly used nanomaterials in the diagnosis and treatment of pancreatic cancer,and has good biocompatibility.Through special surface modification,it can be used in targeted diagnosis and treatment of pancreatic cancer.MIONPs can be used as a contrast agent for MRI,and by modifying the surface,they also can be used in targeted imaging of pancreatic cancer.And they can also be modified as a drug delivery system to achieve targeted delivery of drugs and improve therapeutic effects.However,the application of MIONPs in pancreatic cancer diagnosis and treatment still faces some challenges,such as nanotoxicity and cost issues.With the development of technology,MIONPs are expected to play an important role in the personalized diagnosis and treatment of pancreatic cancer.

Cardiovascular System/pathology* ; Constriction, Pathologic/genetics* ; Point Mutation ; Neurofibromin 1/genetics* ; Animals ; Mice

Objective:To investigate the drug resistance factors in postoperative gemci-tabine chemotherapy after radical resection of pancreatic cancer.Methods:The retrospective case-control study was constructed. The clinicopathological data of 255 patients with pancreatic cancer who were firstly admitted to the Department of Hepatobiliary Surgery of the First Affiliated Hospital of Xi ′an Jiaotong University from January 2018 to June 2021 were collected. There were 140 males and 115 females, aged (59±10)years. All patients underwent radical resection of pancreatic cancer and received postoperative gemcitabine-based adjuvant chemotherapy. Observation indicators: (1) follow-up; (2) postoperative chemotherapy; (3) drug resistance and changing of regimen; (4) factors influencing postoperative chemotherapy resistance. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M( Q1, Q3), and compari-son between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the Pearson chi-square test. Univariate analysis was conducted using the corresponding statistical methods based on data type. Multivariate analysis was conducted using the Logistic regression model with forward method. Kaplan-Meier method was used to draw survival curve, and Log-Rank test was used for survival analysis. Results:(1) Follow-up. All 255 patients were followed up for 18.6(16.7,21.4)months. The median survival time of 255 patients was 18.2[95% confidence interval ( CI) as 15.8-20.6]months. (2) Postoperative chemotherapy. Of the 255 patients, there were 5 cases receiving postoperative chemotherapy as gemcitabine monotherapy, 167 cases receiving postoperative chemotherapy as the AG combination (gemcitabine plus albumin-bound paclitaxel), 74 cases receiving postoperative chemotherapy as the GS combination (gemcitabine plus S-1) and 9 cases receiving postoperative chemotherapy as the GP combination (gemcitabine plus platinum). (3) Drug resistance and changing of regimen. Of the 255 patients, 81 cases completed the course of postoperative chemotherapy and evaluation. Of the 81 patients, there were 18 cases with no recurrence or metastasis of tumor, 10 cases with tumor local recurrence, 40 cases with tumor lymph node metastasis or distant metas-tasis, 3 cases with tumor local recurrence combined with distant metastasis, 10 cases with elevation of CA19-9. Of the 81 patients, 18 cases responded to chemotherapy, 63 cases underwent resistant to chemotherapy, including 11 cases with primary resistance and 52 cases with acquired resistance. The 63 patients with chemotherapy resistance underwent changing of regimen. (4) Factors influencing postoperative chemotherapy resistance. Results of multivariate analysis showed that chemotherapy cycle<6 is an independent risk factor for postoperative chemotherapy resistance in patients ( hazard ratio=17.18, 95% CI as 2.07-142.28, P<0.05). Conclusion:Adjuvant chemotherapy cycle <6 is an independent risk factor for postoperative chemotherapy resistance for gemcitabine based chemo-therapy in pancreatic cancer patients receiving radical resection.

Rutin,a flavonoid found in fruits and vegetables,is a potential anticancer compound with strong anti-cancer activity.Therefore,electrochemical sensor was developed for the detection of rutin.In this study,CoWO4 nanosheets were synthesized via a hydrothermal method,and porous carbon(PC)was prepared via high-temperature pyrolysis.Successful preparation of the materials was confirmed,and character-ization was performed by transmission electron microscopy,scanning electron microscopy,and X-ray photoelectron spectroscopy.A mixture of PC and CoWO4 nanosheets was used as an electrode modifier to fabricate the electrochemical sensor for the electrochemical determination of rutin.The 3D CoWO4 nanosheets exhibited high electrocatalytic activity and good stability.PC has a high surface-to-volume ratio and superior conductivity.Moreover,the hydrophobicity of PC allows large amounts of rutin to be adsorbed,thereby increasing the concentration of rutin at the electrode surface.Owing to the syn-ergistic effect of the 3D CoWO4 nanosheets and PC,the developed electrochemical sensor was employed to quantitively determine rutin with high stability and sensitivity.The sensor showed a good linear range(5-5000 ng/mL)with a detection limit of O.45 ng/mL.The developed sensor was successfully applied to the determination of rutin in crushed tablets and human serum samples.

Objective    To investigate the feasibility and safety of hybrid coronary revascularization (HCR) in patients with multivessel coronary artery disease (MVCAD). Methods    A total of 50 patients with MVCAD who underwent HCR technique in our heart center from May 2016 to April 2019 were included in this study (a HCR group), including 38 patients who underwent two-stage HCR and 12 patients one-stop HCR. There were 39 males and 11 females, with an average age of 62.4 (46-82) years. Another 482 patients who underwent conventional median incision under off-pump coronary artery bypass grafting (OPCAB) at the same period were selected as control (an OPCAB group), including 392 males and 90 females, with an average age of 64.2 (48-84) years. The safety and feasibility of HCR were evaluated and compared with conventional OPCAB technique. Results    There was no perioperative death in both groups. Compared with the OPCAB, HCR was associated with shorter operation time, less chest tube drainage, lower requirement of blood transfusion, shorter mechanical ventilation time and shorter postoperative intensive care unit (ICU) stay (P<0.05). There was no statistical difference in the incidence of major adverse cardiac or cerebrovascular events during the follow-up of 6 to 36 months between the two groups. Conclusion    HCR provides favorable short and mid-term outcomes for selected patients with MVCAD compared with conventional OPCAB.

Objective:To compare the anti-rotation stability between different modes of augmentative plating for femoral shaft nonunion after intramedullary nailing.Methods:Fifteen artificial synthetic femurs were used to create models of femoral shaft nonunion with rotational instability after intramedullary nailing. They were randomly divided into 3 groups ( n=5). Control group 1 was fixated with lateral locking compression plate (LCP), control group 2 with anterior LCP, and the experimental group with anterior multi-dimensional cross locking plate (MDC-LP). After fixation, all the groups were subjected to a torsional loading test, with the torsional loading starting from 0 N·m till 10 N·m and a loading speed of 6°/min. The 3 model groups were compared in terms of torsional angle and stiffness. Results:Under the torsion loading, the torsional angles for control group 1, control group 2 and the experimental group were 9.69°±0.34°, 7.15°±0.20° and 1.59°±0.02°, respectively, showing significant differences ( P=0.002); the torsional angle for the experi mental group was significantly smaller than that for control group 1 ( P<0.05). The torsion stiffness for control group 1, control group 2 and the experimental group was respectively 1.02 N·m/° ±0.04 N·m/°, 1.39 N·m/° ± 0.04 N·m/° and 6.16 N·m/° ± 0.06 N·m/°, showing significant differences ( P=14 886.140, P<0.001); there was a significant difference between any 2 groups ( P< 0.05). Conclusions:In the management of femoral shaft nonunion after intramedullary nailing, anterior augmentative plating can provide better anti-torsional stability than lateral augmentative plating, and MDC-LP can also provide better anti-torsional stability than a conventional LCP because it leads to bicortical fixation of the screws.

Objective    To investigate the effect of postoperative use of levosimendan on patients with valve replacement. Method    Patients with valvular diseases who underwent valve replacement were prospectively enrolled during Jan 2014 to May 2018 in Qingdao Municipal Hospital, randomized to a levosimendan-treated group (n=93) and a control group (n=92) preoperatively. Patients in both groups underwent the same routine treatment preoperatively and postoperatively. In addition, patients in the levosimendan-treated group underwent levosimendan intravenous infusion 24 hours after entering ICU postoperatively. The clinical effect of the two groups was compared. Results    Compared to the control group, the cardiac output(CO, 5.2±1.0 L/min vs. 4.4±1.1 L/min on the seventh day after surgery) and left ventricular ejection fraction (LVEF, 55.7%±2.5% vs. 50.5%±2.2% on the seventh day after surgery) of levosimendan-treated group were increased significantly at different time points(1 day, 3 days and 7 days after surgery)(P<0.05), and the brain natriuetic peptid (BNP) level (312.5±34.6 pg/ml vs. 455.4±45.2 pg/ml on the seventh day after surgery) was less than that of the control group (P<0.05). The dosage (11.5±1.8 mg/kg vs. 20.4±2.1 mg/kg) and administration time of vasoactive agents in the levosimendan-treated group were significantly lower or shorter than those in the control group (70.4±11.2 h vs. 110.5±12.1 h, P<0.05). The ICU stay length, and the total incidence of adverse events were less than those of the control group (P<0.05). Conclusion    Postoperative use of levosimendan immediately after surgery can significantly improve the   cardiac function status of patients who underwent valve replacement, reduce the dosage of vasoactive agents, shorten the time of ICU hospitalization, reduce the incidence of adverse events and enhance the patient’s recovery after valve replacement.