BACKGROUND:At present,the traditional powder sintering method is easy to introduce impurities in the process of preparing porous titanium,and the manufacturing of porous titanium still faces two major problems:impurity pollution and difficult control of the material forming process. OBJECTIVE:To prepare pure porous titanium with certain porosity,and analyze the microstructure evolution and properties of the porous titanium. METHODS:Porous titanium was prepared at a low energy density by selective laser melting technology.The parameter range of porous titanium with large porosity was obtained by measuring the porosity of the formed specimen,and the evolution of the microstructure and mechanical properties of the specimen in the range were analyzed. RESULTS AND CONCLUSION:(1)With the increase in energy density,the porosity of the porous titanium specimen decreased gradually.When the energy density was between 10.61 and 27.78 J/mm3,porous titanium with a porosity of 11.23%-33.67%could be formed.When the energy density was between 27.78-37.88 J/mm3,the forming parts were relatively dense.(2)The phase composition of porous titanium formed was mainly α titanium.With the increase in energy density,the porosity gradually decreased,and the pore morphology changed from irregularly connected pores to closed nearly spherical pores.The powder particles changed from a slightly sintered neck to a continuous fuse.The CT scan results revealed that there were a large number of connected pores in the forming specimen with a large specific surface area and the pore radius was roughly distributed between 2-6 μm at the energy density of 10.61 J/mm3.Simultaneously,porous titanium with compressive strength of 188-1 000 MPa could be obtained at the energy density of 10.61-27.78 J/mm3,which could meet the requirements of biomedical applications.(3)These results have confirmed that the selective laser melting technology can overcome the problems of impurity pollution and long manufacturing cycle caused by the traditional preparation process,and provide an effective solution for the preparation of porous titanium with excellent mechanical properties.

BACKGROUND:For elderly patients with traumatic hip fractures,the related factors of prognosis are very complex,and the integrity of the lateral wall is one of the influencing factors.It is of important clinical value to understand the effect of lateral wall injury on the prognosis of femoral intertrochanteric fracture. OBJECTIVE:To evaluate the relationship between the integrity of the lateral wall and hip functional recovery and other outcomes in patients with femoral intertrochanteric fractures. METHODS:Totally 82 patients with femoral intertrochanteric fractures were screened and all patients received proximal femoral nail antirotation fixation.According to the thickness of the lateral wall,the patients were divided into the lateral wall intact group(n=31)and lateral wall risk group(n=51).The perioperative indexes,weight-bearing time,fracture healing time,hip joint function and range of motion,postoperative pain and complications were compared between the two groups. RESULTS AND CONCLUSION:(1)The time of hospitalization and the number of fluoroscopies during operation in the lateral wall intact group were significantly lower than those in the lateral wall risk group(P<0.05),but there was no significant difference in other perioperative indexes.(2)Both groups were able to get down to the ground early after surgery and finally complete weight-bearing,but in the lateral wall risk group,the time of fracture healing was longer;the time of complete weight-bearing was significantly delayed;the Harris score of the last follow-up was lower;the range of motion of hip extension and flexion and neck trunk angle on the affected side were smaller(P<0.05).(3)There was no significant difference in the incidence of postoperative complications between the two groups,but the overall incidence of complications in the lateral wall intact group was significantly lower(P<0.05).(4)In summary,after internal fixation of proximal femoral nail antirotation,patients with the intact lateral wall had a relatively better prognosis than those with risk lateral wall.

Objective To investigate the clinical efficacy of percutaneous closure of foramen ovale guided by transthoracic echocardio-graphy with simply delivery sheath.Methods The clinical data of patients with patent foramen ovale underwent interventional closure and percutaneous closure guided by transthoracic echocardiography with simply delivery sheath in our hospital from January 2020 to December 2022 were analyzed retrospectively,the patients were divided into interventional closure group(40 cases)and simply delivery sheath group(39 cases).The operation time,incidence of surgical complications,and surgical success rates of patients in the two groups were compared.The closure effect were evaluated by ultrasound immediately after surgery.All the patients were followed up for 6 months after surgery to evaluate remission of the symptoms.Results The surgical success rate of simply delivery sheath group(100%)was higher than that of interventional closure group(90.0%),with statistically significant difference(P<0.05).The operation time of simply delivery sheath group was longer than that of interventional closure group,with statistically significant difference(P<0.05).One patient in the interventional closure group had small amount of pericardial effusion during the operation.Two patients had decreased blood pressure and slowed heart rate in simply delivery sheath group,and symptoms disappeared after treatment.There was no significant difference in the incidence of complications between the two groups(P>0.05).After 6-month follow-up,all occluders were in good position and no residual leakage was found.The symptoms of headache or dizziness disappeared in 28 patients in interventional closure group,significantly relieved in 8 patients;the symptoms of headache or dizziness disappeared in 30 patients in simply delivery sheath group,and significantly relieved in 9 patients.Conclusion Percutaneous closure for patent foramen ovale under the guidence of transthoracic echocardiography with simply delivery sheath is safe and feasible with satisfactory efficacy and higher successful rate without radiation hazard.It is worthy of clinical promotion.

Objective To investigate the dietary patterns of rural residents in the high-incidence areas of esophageal cancer (EC), and to explore the clustering and influencing factors of risk factors associated with high-incidence characteristics. Methods A special structured questionnaire was applied to conduct a face-to-face survey on the dietary patterns of rural residents in Yanting county of Sichuan Province from July to August 2021. Univariate and multivariate logistic regression models were used to analyze the influencing factors of risk factor clustering for EC. Results There were 838 valid questionnaires in this study. A total of 90.8% of rural residents used clean water such as tap water. In the past one year, the people who ate fruits and vegetables, soybean products, onions and garlic in high frequency accounted for 69.5%, 32.8% and 74.5%, respectively; the people who ate kimchi, pickled vegetables, sauerkraut, barbecue, hot food and mildew food in low frequency accounted for 59.2%, 79.6%, 68.2%, 90.3%, 80.9% and 90.3%, respectively. The clustering of risk factors for EC was found in 73.3% of residents, and the aggregation of two risk factors was the most common mode (28.2%), among which tumor history and preserved food was the main clustering pattern (4.6%). The logistic regression model revealed that the gender, age, marital status and occupation were independent influencing factors for the risk factors clustering of EC (P<0.05). Conclusion A majority of rural residents in high-incidence areas of EC in Yanting county have good eating habits, but the clustering of some risk factors is still at a high level. Gender, age, marital status, and occupation are influencing factors of the risk factors clustering of EC.

Objective To investigate the application value of Revolution CT dual-low technique coronary angiography in coronary heart disease.Methods One hundred patients with suspected coronary heart disease were retrospectively selected and randomly divided into control group and observation group,who all were examined by Revolution CT.In the control group(50 cases),the tube voltage was 120 kV,the contrast agent iohexol was 350 mg I/mL,and the dose of contrast agent was 1 mL/kg.In the observation group(50 cases),the tube voltage was 100 kV,the contrast agent iohexol was 350 mg I/mL,and the dose of contrast agent was 0.8 mL/kg.All patients underwent coronary digital subtraction angiography(DSA)examination at the same time.The image quality(subjective and objective evaluation indexes)and radiation dose of the two groups were compared,the diagnostic value of the two methods for coronary artery stenosis was compared,and the diagnostic consistency with coronary DSA between the two methods were compared using the Kappa test,as well as the typical coronary images of the two groups were analyzed.Results There were no significant differences in the sub-jective image quality grade and excellence rate between the observation group and the control group(P＞0.05).The CT value and noise of the observation group were higher than those of the control group(P＜0.05).There were no statistically significant differ-ences in the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of the right coronary proximal and the left coronary main trunk between the two groups(P＞0.05).Compared with the control group,the volume CT dose index(CTDIvol),dose length product(DLP),and effective dose(ED)were lower in the observation group(P＜0.05).Compared with the results of coronary DSA,the positive predictive value,negative predictive value,sensitivity,specificity and accuracy of the two methods were＞80％,while there was no significant difference between the two groups(P＞0.05).The Kappa value of the observation group versus coronary DSA diagnosis was 0.871,the Kappa value of the control group ver-sus coronary DSA diagnosis was 0.889,and the consistency of both methods versus coronary DSA diagnosis was good.Conclusion Revolution CT dual-low technigue coronary angiography has good diagnostic value for coronary heart disease and can significantly reduce the radiation dose while ensuring image quality.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective To establish a new animal model of filum terminale traction tethered cord syndrome to explore its pathogenesis.Methods Sixteen New Zealand white rabbits were randomly divided into the traction group and the sham group,with 8 rabbits in each group.The traction group used silk thread to establish a model of filum terminale traction tethered cord syndrome,while the sham group only cut the filum terminale without traction.After 8 weeks,the behavioral Talov score,lumbosacral MRI examination,somatosensory evoked potential detection,urodynamic index test and pathological analysis were completed.Results At the 8th week after surgery,the hindlimb injury was obvious in the traction group,and the Talov scores at the 4th and 8th weeks after operation were lower than those in the sham group(P<0.001).The lumbosacral MRI results at 8 weeks after surgery showed that the distal filum terminale was pulled by silk thread,with bladder abnormal enlargement in sagital MRI in the traction group,while axial MRI showed the spinal cord within the spinal canal was subjected to mechanical forces in the downward and dorsal directions;the sagittal and axial MRI of the sham group showed that the spinal cord was located in the middle of the spinal canal and the bladder size was normal.At the 8th week after surgery,the amplitude in the traction group was significantly lower than that in the sham group(P<0.001),and the amplitude decreased by more than 50% .The overall latency period in the traction group was slightly longer than that in the sham group(P<0.05).The results of urodynamic examination showed that the maximum bladder capacity in the traction group was significantly higher than that in the sham group(Z=-3.361,P<0.001),the bladder pressure was significantly lower than that in the sham group(Z=-3.361,P<0.001),and the bladder compliance was significantly higher than that in the sham group(P<0.001).Pathological staining showed that the traction of the filum terminale on the spinal cord led to nerve tissue damage and degeneration of bladder epithelial cells.Conclusion This study successfully established a model of filum terminale traction tethered cord syndrome of New Zealand white rabbits,which can provide reference for exploring the pathogenesis of tethered cord and understanding the pathological process of spinal cord injury.

Objective To investigate the effect of varying ureteral wall thickness(UWT)at the site of ureteral stones on the clinical efficacy of ureteroscopic lithotripsy(URL).Methods The clinical data of 164 patients with ureteral stones in our hospital were retrospectively analyzed.According to different UWT,the patients were divided into the mild thickening group(84 cases,UWT<3.16 mm),the moderate thickening group(31 cases,UWT 3.16 to 3.49 mm),and the severe thickening group(49 cases,UWT>3.49 mm),and the differences of clinical related indicators among the three groups were compared.Results The incidence of postoperative renal colic and leukocyte disorder in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,and the differences were statistically significant(P<0.05).The postoperative catheterization time in the mild thickening group and the moderate thickening group were shorter than that in the severe thickening group,and the incidences of secondary lithotripsy,residual stones and stone return to kidney in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,with statistically significant differences(P<0.05).The length of hospital stay and hospitalization cost in the mild thickening group and the moderate thickening group were shorter/less than those in the severe thickening group,with statistically significant differences(P<0.05).Conclusion With the increase of UWT(especially when UWT>3.49 mm),the incidence of postoperative complications and hospitalization cost of URL increase to varying degrees,and the surgical efficacy decreases.In clinical work,UWT measurement holds potential value in predicting the surgical efficacy and complications of URL.

As an important part of the enteric nervous system(ENS),enteric glial cells(EGCs)play an important role in regulating intestinal homeostasis and maintaining intestinal health in hu-mans and animals.This review focuses on the role of EGCs in maintaining intestinal barrier homeo-stasis,maintaining gastrointestinal transit and motor function,regulating the niche of intestinal cells,and the role in the occurrence and development of intestinal diseases,hoping to provide new ideas for further research on the function and mechanism of EGCs in the intestine and the occur-rence,development and treatment of related intestinal diseases.

The imprint desorption electrospray photoionization mass spectrometry was employed to locally image the spatial distribution of chemical components in dried tobacco leaves after initial curing. The relative content distribution of different chemical components was obtained in tobacco leaves. The application of imprinting method could transfer tobacco internal compounds to the surface of porous polytetrafluoroethylene plate,which realized the detection and visual analysis of tobacco internal substances. Besides,the imprint desorption electrospray ionization/post-photoionization (Imprint DESI/PI) mass spectrometry imaging technique had the advantages of non-polarity discrimination,soft ionization and high ionization efficiency for plant samples,and could simultaneously detect and image rich compounds in tobacco samples. A total of 40 kinds of chemical components including alkaloids,amino acids,sugars,acids,ketones and phenols were identified based on high resolution mass spectrometry. The results showed that the representative chemical components of tobacco,such as alkaloids,amino acids and sugars,were mainly distributed near the leaf tip from the vertical analysis and at the left and right leaf edges from the horizontal analysis. Amadori compound (1-Deoxy-1-L-proline-d-fructose) was detected,and the content of Amadori was found to be consistent with that of free amino acid (proline). In addition,the technique was further used to study the climate spot disease area of tobacco,and it was found that the compounds had specific distribution in the climate spot area,which further proved the superiority of this method in studying the growth stress of tobacco leaves.