In CT examination,micro-offsets of±1-2 mm in CT laser-positioning systems may compromise clinical diag-nostic accuracy even when they remain below the equipment failure threshold.This paper analyzes the technical differences of CT laser positioning systems from different manufacturers and constructs a multidimensional micro-offsets detection system that com-bines phantom detection measurements,image backtracking analysis algorithm,and real-time monitoring technology.Integrating the clinical experience of multiple medical institutions,we proposed a brand-and anatomy-specific calibration strategy and explore the impact of micro-offsets on scanning accuracy and radiation dose.The strategy was verified in two clinical cases:in neurosur-gery,a Siemens CT positioning offset caused tumor residue,and after intervention the target deviation rate dropped to 0;in ortho-pedics,a GE CT offset forced a surgical plan revision,and post-intervention the plan-matching rate reached 100％.These results provide both a systematic theoretical foundation and standardized operating procedures for clinical practice.

In CT examination,micro-offsets of±1-2 mm in CT laser-positioning systems may compromise clinical diag-nostic accuracy even when they remain below the equipment failure threshold.This paper analyzes the technical differences of CT laser positioning systems from different manufacturers and constructs a multidimensional micro-offsets detection system that com-bines phantom detection measurements,image backtracking analysis algorithm,and real-time monitoring technology.Integrating the clinical experience of multiple medical institutions,we proposed a brand-and anatomy-specific calibration strategy and explore the impact of micro-offsets on scanning accuracy and radiation dose.The strategy was verified in two clinical cases:in neurosur-gery,a Siemens CT positioning offset caused tumor residue,and after intervention the target deviation rate dropped to 0;in ortho-pedics,a GE CT offset forced a surgical plan revision,and post-intervention the plan-matching rate reached 100％.These results provide both a systematic theoretical foundation and standardized operating procedures for clinical practice.

Objective To investigate the value of predicting the pathological results of labial gland biopsy in Sj?gren's syndrome(SS)based on the labial gland MRI radiomics machine learning models.Methods The labial gland MRI data of 178 suspected SS patients were analyzed retrospectively,and the labial gland biopsy pathology results were positive in 97 cases and negative in 81 cases.The samples were divided into training set(143 cases)and test set(35 cases)using a randomized stratified sampling according to the ratio of 4:1.The region of interest(ROI)was manually outlined at the maximal level of the lower labial gland in T2WI water phase and radiomics features(104)were extracted.Feature screening was performed using the least absolute shrinkage and selection operator(LASSO),and the selected features set was used to construct Extra Trees,LightGBM,and Gradient Boosting classifier models.The predictive efficacy of the models was evaluated using the receiver operating characteristic(ROC)curve,and the DeLong test was used to compare the differences in the area under the curve(AUC)between the models.Decision curve analysis(DCA)was used to evaluate the clinical application value of the models in guiding biopsy.Results After LASSO screening,five optimal radiomics features were obtained.The AUC of Extra Trees,LightGBM,and Gradient Boosting models on the training and test sets were as follows 1.000,0.807,0.960 and 0.655,0.779,0.639,respectively.The DeLong test showed no statistically significant difference in AUC among the three models in the test set.DCA showed that the LightGBM model of guided biopsy had a higher clinical net benefit over a wider range of risk thresholds than other models.Conclusion Based on the radiomics features of the labial gland T2WI water phase,the LightGBM model has a high accuracy in predicting the pathological results of labial gland biopsy in SS,and guiding biopsy can obtain high clinical benefits,which has potential clinical application value.

OBJECTIVE:To investigate the application of fuzzy comprehensive evaluation in formulation screening. METH-ODS:Taking Compound paracetamol and chlorphenamine maleate granules as model drug,based on single factor experiment,L9(34) orthogonal test was used to screen the formulation with the amount of aspartame,hawthorn powder essence,milk powder essence and saccharose as factors,using dissolution rate of caffeine as index. The granules prepared by 9 kinds of formulation in orthogonal test were evaluated with fuzzy comprehensive evaluation in terms of taste,aroma,color and dissolubility. The optimized formula-tion was validated and compared with original formulation. RESULTS:The formulation 5 was the optimal choice in both orthogo-nal test and fuzzy comprehensive evaluation,and obtained same results. Compared with sensory comprehensive score (63.12) and dissolution rate of caffeine (91.3%) in original formulation,two indicators of optimized formulation in 3 tests were 84.00 and 99.07% in average (RSD<2.0%,n=3). CONCLUSIONS:Fuzzy comprehensive evaluation can be used for the formulation screening of sensory evaluation index. It is scientific and accurate.

[Objective] To observe the anti-aging actions of total saponins of Radix Notoginseng, i.e., Panax Notoginseng saponins (PNS) on rats with Alzheimer's Disease (AD). [Methods] Among 90 Wistar rats, 15 rats aged 3 months were allocated to the youth group, 15 aged 15 months to the aged group, and other 60 aged 15 months were given with intraperitoneal injection of D-galactose and injection of ibotenic acid into bilateral Meynert nucleus basalis to establish the models of AD. After then, the surviving model rats were randomized into four groups: model control, high-dose PNS (200mg?kg-1?d-1), low-dose PNS (100 mg?kg-1?d-1) and huperzine A (0.3 mg?kg-1?d-1). Except the model group, the youth group and the aged group were given the same amount of normal saline by gavage, the other groups were treated with the designed drugs respectively for 4 weeks. After treatment, serum levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), triglyceride (TG) and cholesterol were detected. [Results] High- and low-dose PNS increased the serum levels of SOD, GSH and CAT, the differences being significance as compared with the model group (P