Objective:To systematically search and evaluate risk prediction models for ventilator-associated pneumonia (VAP) of ICU in order to provide references for developing higher-quality VAP risk prediction models.Methods:Relevant literature was retrieved from databases including China Biology Medicine disc, WanFang data, China National Knowledge Infrastructure, Embase, PubMed, CINAHL, Web of Science, and Cochrane Library. The search timeframe was from the establishment of the databases to September 30, 2023, limited to English and Chinese languages. Two researchers independently screened the literature and extracted data, and the PROBAST tool was used to evaluate the risk of bias and applicability of the included studies.Results:A total of 15 studies on VAP risk prediction models were included. The area under the receiver operating characteristic curve for the 15 models ranged from 0.722 to 0.982. The most frequently involved predictors were age, duration of mechanical ventilation, ICU length of stay, and comorbid chronic obstructive pulmonary disease. The overall adaptability was good, but the risk of bias was high. The main sources of bias included insufficient sample size, inappropriate data sources, lack of model performance evaluation, and inadequate attention to missing data.Conclusions:The risk of bias in studies on VAP risk prediction models is high, indicating that the field is still developing. Future research should focus on the effectiveness of different risk assessment methods to construct models with low bias, excellent predictive performance, and suitability for clinical practice in China.

Objective To explore the mechanism of Gualou Xiebai Baijiu Decoction(GXB)in improving atherosclerosis(AS)in mice by regulating the gut microbiota(GM)and its metabolites.Methods Thirty-two male ApoE-/-mice were divided randomly into a Blank group,Model group,atorvastatin(Ato)group,and GXB group(n=8 mice per group).AS was established in all mice,except the Blank group,and the respective treatments were administered by gavage.Aortic plaques were detected by Oil red O staining and pathological changes in aortic tissue were detected by hematoxylin and eosin staining.The GM was analyzed using 16S rRNA gene sequencing technology,and mouse GM metabolites,including trimethylamine oxide(TMAO),short-chain fatty acids(SCFA),and serum levels of triglycerides(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),and nitric oxide(NO)were determined.Results Compared with the Blank group,mice in the Model and Ato groups showed an increase in AS plaque area(P＜0.05).Serum levels of TG,TC,and LDL-C were increased(P＜0.001)while levels of HDL-C and NO were decreased(P＜0.01,P＜0.001)in the Model group compared with the Blank group.The plaque area was decreased(P＜0.05),serum levels of TG,TC,and LDL-C were decreased(P＜0.001),and NO levels were increased(P＜0.01)in the Ato and GXB groups,while HDL-C levels were increased in the GXB group(P＜0.05)compared with the Model group.Plaque area was decreased(P＜0.05)and the NO level was increased(P＜0.01)in the GXB group compared with the Ato group.A total of 6345 characteristic sequences were obtained from 16S rRNA analysis.α-Diversity analysis indicated that GXB reduced the richness of the GM in AS mice(P＜0.001)and improved its uniformity(P＜0.05).β-Diversity analysis suggested that the microbial community structure in the GXB group was similar to that in the Blank group.The abundance of microbial communities differed among the groups at the phylum and genus levels.At the phylum level,the abundance of Proteobacteria was increased(P＜0.01)in AS mice,while GXB intervention reduced the abundance of Proteobacteria(P＜0.01)and increased the abundance of Verrucomimicrobiota(P＜0.05).At the genus level,GXB effectively increased the abundance of Akkermansia(P＜0.05).SCFAs were significantly increased(P＜0.01)and TMAO levels were significantly decreased(P＜0.01)in the GXB group compared with the Model group.Conclusions GXB can regulate the intestinal flora and intestinal flora metabolites SCFA and TMAO to improve AS.Akkermansia may be a key bacterial genus of the gut microbiota through which GXB may improve AS.

Purpose To explore the value of ultrasonography in distinguishing periductal mastitis(PDM)from granulomatous lobular mastitis(GLM)and summarize the sonographic features of non-puerperal mastitis(NPM).Materials and Methods The ultrasonographic findings of 134 NPM(84 PDM,50 GLM)patients treated in the Second Hospital of Lanzhou University from July 2016 to June 2021 were retrospectively analyzed.Comparing PDM and GLM sonograms,the difference of lesion number,lesion side,lesion orientation,distance from the nipple,long diameter,thick diameter,aspect ratio,boundary,edge,edge,shape,internal echo,peripheral high echo halo,rear echo,calcification,internal blood flow,ipsilateral axillary lymph node enlargement,and summarize the characteristics of NPM according to the lesion morphology and internal echo.Results There was no statistical difference between PDM and GLM(P＞0.05).But the probability of PDM combined with ipsilateral axillary lymph node enlargement was slightly higher than that of GLM(x2=4.209,P=0.040).The ultrasonography of 134 cases of NPM lesions was divided into 7 types according to the morphology and echo changes.The abscess type was more common in GLM than in PDM(x2=4.928,P=0.026).Conclusion There is no significant difference between PDM and GLM.In the case that PDM and GLM cannot be distinguished clinically and radiologically,it is recommended to perform puncture biopsy to determine the pathological type before treatment,which may be more conducive to obtaining the best prognosis for patients.In addition,the classification of NPM into 7 types is helpful for sonographers to grasp the ultrasonographic characteristics of NPM to diagnose NPM early.

Objective:To explore the effectiveness of body weight support in gait training after surgery for an ankle fracture.Methods:Thirty-eight ankle fracture patients who received surgery were divided at random into an observation group and a control group, each of 19. In addition to 3 sessions of routine gait rehabilitation training a week for 6 weeks, only those in the observation group received body weight support training with body weight support boots. Gait data were collected using the GaitWatch three-dimensional gait action capture and training system before the training and after 2, 4 and 6 weeks of the training.Results:At each assessment the gait frequency, gait cycle, stride length, stride rate, bilateral step length, step length deviation, bilateral support phase and bilateral swing phase of both groups had improved significantly. After 6 weeks the average stride frequency, gait cycle, stride length on both sides and speed of the observation group had improved significantly more than among the control group. Step length deviation was not significantly different, however. At each evaluation the proportions of affected and healthy side support had decreased significantly in both groups, but affected and healthy side swing had increased and the proportion of bilateral support had decreased significantly.Conclusion:Body weight support training with body weight support boots can significantly improve gait after ankle fracture surgery. Its effect is superior to that of conventional gait training.

Objective:To explore the value of multiparametric ultrasonography consisting of gray-scale ultrasound(US), color Doppler flow imaging (CDFI), real-time strain elastography(RTE), and contrast-enhanced ultrasound(CEUS) in the differential diagnosis of testicular lesions.Methods:Forty patients (40 lesions) detected by ultrasonography examination at the Ultrasound Medical Center of Lanzhou University Second Hospital from June 2020 to June 2022 were retrospectively analyzed, and further the CDFI, CEUS and RTE were performed. The presence of vascularization in the lesion was determined by CDFI and CEUS, avascular lesions were defined as benign, vascularization lesions were defined as malignant. The lesion tissue elasticity was assessed by real-time strain elastography, tissue stiffness was encoded as red(soft), green(intermediate), and blue(hard), and the hard lesions were defined as malignant, soft lesions were defined as benign. All lesions were subjected to pathological histologic examination after surgical resection or puncture biopsy as a reference standard. The correct classification rate, sensitivity, specificity and likelihood ratio of the multiparametric ultrasonography imaging for the diagnosis of benign and malignant testicular lesions were analyzed by ROC.Results:Of 40 testicular lesions, 24 (60.0%) were benign and 16 (40.0%) were malignant. The sensitivity of CDFI, CEUS and RTE in the diagnosis of testicular lesions was 0.875, 1.000 and 1.000, and the specificity was 0.833, 0.750 and 0.708, respectively. The correct classification rate was 85.0%, 85.0% and 82.5%, and the positive likelihood ratio was 5.24, 4.00 and 4.42, respectively. AUC was 0.781, 0.802, 0.771, respectively. By combining RTE and CDFI, a sensitivity of 1.000 and specificity of 0.875 and correct classification rate of 92.8% and positive likelihood ratio of 8.00 and AUC of 0.915 ( P<0.001) were achieved in differentiating testicular lesions. And combining RTE and CEUS, achieved sensitivity of 1.000 and specificity of 0.917 and correct classification rate of 95.0% and positive likelihood ratio of 12.0 and AUC of 0.958( P<0.001). Conclusions:Multiparametric US is of great value in the differential diagnosis of benign and malignant testicular lesions.

Abstract Myopia is a common refractive error in the process of development. With the high incidence and low age of myopia in children and adolescents, it has become a worldwide public health problem, seriously endangering physical and mental health. The prevention and control of myopia has a long way to go. Low concentration atropine, as an M type choline receptor inhibitor, has been proved by medical research to effectively delay the progress of myopia. This paper reviews the relevant studies at home and abroad in recent years. The optimal concentration of low concentration atropine, the best clinical regimen and possible potential side effects were discussed. From the point of view of school public health, this paper discusses the significance of low concentration atropine for the prevention and control of myopia among school age students, in order to provide a reliable basis and new ideas for the follow up clinical application of atropine and myopia prevention and control strategies for school students.

Objective:To evaluate the value of synthetic MRI combined with DWI in the diagnosis of benign and malignant breast lesions.Methods:The data of 184 consecutive patients with suspected breast lesions in Yunnan Cancer Hospital from July to September 2019 were prospectively analyzed. All patients were randomly assigned to training group ( n=110) and validation group ( n=74), and underwent conventional MRI and synthetic MRI respectively before and after contrast injection. At the maximum slice of the lesion, the ROI was drawn along the edge and recorded as "tumor". In the solid area with the most obvious tumor enhancement, the second ROI was drawn and recorded as "local". At the same time, ADC values (ADC local and ADC tumor) and relaxation time values (T local and T tumor) were measured. T and T + represented the relaxation time value of the ROI pre-and post-contrast scanning. ΔT% represented the relative change rate in T value between pre-and post-contrast scanning.The rank sum test was used to test the quantitative parameters of benign and malignant breast lesions in the training group and the validation group, and the variables with P<0.05 were included in the binary logistic regression analysis to screen the independent variables and establish the prediction model. The area under ROC curve was used to evaluate the discrimination of parameters and models. The clinical applicability of model was analyzed by decision curve analysis (DCA). Results:In the training group, univariate analysis showed that there were significant differences in T 1tumor, T 1+tumor, ΔT 1% tumor, T 2local, T 2+local, T 2tumor and T 2+tumor, ADC local, ADC tumor between benign and malignant breast lesions ( P<0.05). Multivariate logistic regression analysis showed that T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor were independent variables in the diagnosis of breast cancer. The relaxation time model (model A: T 1+tumor, ΔT 1% tumor, T 2tumor) and ADC model (model B: ADC local, ADC tumor) established by combining the above variables had the same diagnostic efficiency (AUC=0.905, 0.914, Z=-1.874, P=0.062), and the multi-parameter combination model (model C: T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor) had the highest diagnostic efficiency (AUC=0.965). DCA analysis showed that when the threshold probability ranges between 21%-99% (training cohort) and 15%-99% (validation cohort), the net benefit of model C was better than model A and B. Conclusion:The multi-parameter combined prediction model established based on the relaxation time value and ADC can identify breast cancer efficiently and can be used as an auxiliary diagnostic tool.

Objective:To establish a method for the determination of mandelic acid and phenylglyoxylic acid in the urine of styrene by dispersive liquid-liquid microextraction-high coupled with high performance liquid chromatography.Methods:N-octanol was used as an extractant and ethanol was used as a dispersing agent. The phenylglycolic acid and phenylglyoxylic acid in the urine were extracted, and the upper liquid was taken after vortexing and centrifuged, and then was injected into HPLC for analysis.Results:The linear correlation coefficient of the concentration of phenylglycolic acid in the range of 0~10.0 mg/L was greater than 0.999. The detection limit of the method was 9.9 μg/L, the recovery rates were 86.1%~101.6%. The intraday RSDs of the method were 1.07%~3.76%, and the interday RSDs were 1.24%~3.33%. The linear correlation coefficient of phenylglyoxylic acid in the range of 0.0~2.0 mg/L is greater than 0.999. The detection limit of the method was 2.6 μg/L, the recovery rates were 88.8%~100.3%. The intraday RSDs of the method were 1.02%~ 3.17%, and the interday RSDs were 1.59%~2.41%.Conclusion:The method has low detection limit, high enrichment ratio and good sensitivity, and is suitable for determination of phenylglycolic acid and phenylglyoxylic acid in urine of occupational exposure to styrene.

Objective:To establish a method for the determination of mandelic acid and phenylglyoxylic acid in the urine of styrene by dispersive liquid-liquid microextraction-high coupled with high performance liquid chromatography.Methods:N-octanol was used as an extractant and ethanol was used as a dispersing agent. The phenylglycolic acid and phenylglyoxylic acid in the urine were extracted, and the upper liquid was taken after vortexing and centrifuged, and then was injected into HPLC for analysis.Results:The linear correlation coefficient of the concentration of phenylglycolic acid in the range of 0~10.0 mg/L was greater than 0.999. The detection limit of the method was 9.9 μg/L, the recovery rates were 86.1%~101.6%. The intraday RSDs of the method were 1.07%~3.76%, and the interday RSDs were 1.24%~3.33%. The linear correlation coefficient of phenylglyoxylic acid in the range of 0.0~2.0 mg/L is greater than 0.999. The detection limit of the method was 2.6 μg/L, the recovery rates were 88.8%~100.3%. The intraday RSDs of the method were 1.02%~ 3.17%, and the interday RSDs were 1.59%~2.41%.Conclusion:The method has low detection limit, high enrichment ratio and good sensitivity, and is suitable for determination of phenylglycolic acid and phenylglyoxylic acid in urine of occupational exposure to styrene.

Objective : To analyze the initial displacement of the upper central incisor and stress distribution of periodontal ligament under different torque values of upper incisors under the action of a four-curved auxiliary arch to provide a reliable basis for the safety of clinical application of four-curved auxiliary arches. Methods : A three-dimensional finite element model for torque control of upper anterior teeth with a homemade quadrilateral auxiliary arch was established. Four different states were analyzed: molar ligation without extraction space (group A), microimplant ligation without extraction space (group B), molar recovery with extraction space closure (group C) (the adductive traction force was set at 115 g) and microimplant recovery with extraction space closure (group D) (the adductive traction force was set at 115 g). When four types of torque (0.5 N, 1.0 N, 1.5 N, and 2.0 N) were applied. The initial displacement of upper central incisors and the stress distribution of periodontal ligament in 16 groups (A1-A4, B1-B4, C1-C4, D1-D4) were observed. Results : Under different conditions, as the strength of the four-curve auxiliary arch increases, the maxillary anterior teeth has crown labial inclination and a root lingual inclination. The displacement of the incisor tip increases with the increase in the loading force of the torque auxiliary arch, and the displacement of the incisor root apex increases as the force increases. The difference in incisor-apex displacement distance in A1-A4, B1-B4, C1-C4, D2 and D4 groups increased as the torque force increases, while the difference between the D3 group and D1 and D2 groups decreased slightly. The stress of the cervical periodontal ligament of the upper central incisor did not exceed the stress of the periodontal ligament in the following groups: A1, A2, B1, B2, B3, C1, C2, D1, and D2. The stress of the lip side of the upper central incisor did exceed the stress of the periodontal ligament in the following groups: A3, A4, B4, C3, C4, D3, and D4. In other words, when using the four-curved auxiliary arch as an implant anchorage, the force applied in the absence of extraction space should not exceed 1.5 N, and the force applied in the adduction of extraction space should not exceed 1.0 N. When using the nonimplant anchorage, the force applied in the absence of extraction space and the adduction of extraction space should not exceed 1.0 N. In addition, the range of force should not exceed the maximum stress of the periodontal ligament in the cervical region such that the effective and safe torque movement can be achieved. Under other stress conditions, the stress of the labial and cervical periodontal ligament of the upper central incisor exceeded the stress value (2.6 × 10-2MPa). The stress value of periodontal ligament was 2.6 × 10-2MPa in all groups. Conclusion A four-curved auxiliary arch has a significant effect on the upper anterior teeth, and the use of microimplants can better control root movement such that the crown of upper central incisors cannot be excessively lip inclined.