Objective To explore the value of minute ventilation recovery time (VERT) as a weaning predictor in mechanically ventilated patients with chronic obstructive pulmonary disease (COPD).Methods A prospective study was performed from March 2008 to July 2012.Fifty-two COPD patients under mechanical ventilation for more than 48 hours in our RICU tolerated a spontaneous breathing trial (SBT) and were ready for planned extubation.After SBT,these patients were placed back on their pre-SBT ventilator settings for up to 25 minutes,during which VERT was obtained.VERT was defined as the time for minute ventilation to return to baseline measured before SBT.Respiratory rate,tidal volume,minute ventilation and respiratory rate/tidal volume ratio were also obtained before SBT and just after SBT.Arterial blood gas data were measured and recorded before weaning.According to the weaning outcome,the patients were classified as successful group (40 cases) or failed group (12 cases).VERT and other quantitative variables were compared using t test.A multiple logistic regression was performed to explore possible factors associated with the weaning outcome.The sensitivity and specificity of VERT for predictive capacity in weaning were assessed using ROC cure.Results VERT and respiratory rate after SBT were significantly different between two groups.Multiple logistic regression revealed that VERT was the only predictor associated with weaning outcome (b =0.282,P ＜0.001).The area under ROC curve for VERT was 0.957 (95％ CI:O.907-1.008).With a cut-off value of 10.5 minutes,the sensitivity and specificity of VERT for predicting weaning failure were 1.0 and 0.85,respectively.Conclusions VERT may be a new predictor for extubation and determination of mechanical ventilation weaning in patients with COPD.VERT is a variable to be easily measured thereby being conveniently used in clinical practice.

Objective Kidney-supplementing and blood-activating method was adopted in treating senile patients with isolated systolic hypertension to observe its decompression effects and influences on microalbunminuria (Malb),retinol binding protein (RBP) level in 24 hours.Methods 90 patients with simple systolic hypertension were randomly recurited into two groups.52 cases in the treatment group were administered with kidney-supplementing and blood-activating decoction,including 1 case falling off and 51 cases entering statistical analysis; 38 cases in the control group were administered with oral placebo,among them 2 cases were fallen offand 36 cases were entered statistical analysis.Both groups were treated for 8 weeks.Results () Blood pressure:systolic blood pressure at 4 and 8 weeks after the treatment in the treatment group [(144.03±12.33)mmHg (1 mmHg=0.133kPa) and (132.27±13.15)mmHg] wassignificantlyimproved than before the treatment [(156.32±12.05)mm Hg] (P＜0.05),and also significantly better than the control group at 4,8 weeks after the treatment [(151.19± 13.83)mm Hg,(152.74± 12.03)mm Hg] (P＜0.05).②The Malb,RBP level:Malb,RBP level [(40.80±13.51)mg/L,(150.43±23.62)mg/L] after the treatment in the treatment group was reduced than before the treatment [(50.14± 15.61)mg/L,(220.04±30.20) mg/L] (P＜0.05),and was significantly different to the control group after treatment [(52.12±14.69)mg/L,(219.34±34.37)mg/L] (P＜0.05).Conclusion Kidney-supplementing and blood-activating method can improve kidney function,and thus to reduce the effect of systolic blood pressure.

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.

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 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.

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.