The intricate anatomical architecture and complex dynamic physiological barriers of the eye severely restrict the intraocular bioavailability of ophthalmic drugs. The limited absorption efficiency of conventional eye drops(<5%)and the highly invasive nature of intravitreal injections remain persistent bottlenecks in ophthalmic therapeutics. Driven by the convergence of materials science and biomedical engineering, intelligent stimuli-responsive drug delivery systems offer revolutionary strategies to overcome these physiological barriers and achieve spatiotemporally controlled drug release. These systems leverage specific recognition and response capabilities targeted at pathological microenvironments or exogenous physical fields. This article systematically reviews recent advances in this domain, providing an in-depth analysis of the physicochemical mechanisms underlying various stimuli-responsive carriers from the perspectives of polymer phase transition thermodynamics and chemical bond cleavage kinetics. By synthesizing preclinical and clinical research data on major ocular diseases, including glaucoma, age-related macular degeneration, and intraocular infections, the significant advantages of these intelligent systems were demonstrated. Highlighted benefits include prolonged ocular surface retention, biomarker-triggered on-demand release, and minimized systemic toxicity. Finally, this review critically analyzes the challenges of translating these complex formulations to the clinic, specifically regarding sterile scale-up manufacturing and regulatory approval pathways, while providing perspectives on future development.

Objective To investigate the value of contrast-enhanced ultrasound(CEUS)combined with shear wave elastography(SWE)in the diagnosis of liver tumors.Methods This study was conducted according to the PRISMA guideline,with a PROSPERO registration number of CRD42023491288.PubMed,Embase,the Cochrane Library,CNKI,VIP,and Wanfang Data were searched for articles on CEUS combined with SWE in the diagnosis of liver tumors published from January 2000 to October 2023,and a total of 12 articles were included,with 1 328 patients in total.The QUADAS-2 tool was used to assess the quality of the articles included.Stata 15.0 software was used to calculate pooled sensitivity,specificity,positive likelihood ratio,negative likelihood ratio,diagnostic odds ratio,and heterogeneity.The summary receiver operating characteristic(SROC)curve was plotted,and the area under the SROC curve(AUC)was calculated.Results There were 1 457 lesions for the patients included,among whom there were 764 malignant lesions and 693 benign lesions,with a positive rate of 52.44%and a negative rate of 47.56%.Calculations obtained a pooled sensitivity of 0.94(95%confidence interval[CI]:0.91—0.96),a specificity of 0.92(95%CI:0.87—0.95),a positive likelihood ratio of 12.00(95%CI:7.40—19.40),a negative likelihood ratio of 0.06(95%CI:0.04—0.10),and a diagnostic odds ratio of 191(95%CI:87—417).The tests for heterogeneity showed Q=54.78,df=11.00,P<0.001,and I2=79.92%(95%CI:69.18%—90.66%),with an AUC of 0.98.Conclusion CEUS combined with SWE has a relatively high diagnostic value for benign and malignant liver tumors and thus holds promise for clinical application.

Objective:To explore an efficient method of practical teaching for ultrasonography.Methods:There were 41 five-year clinical medical students intending to learn ultrasonography in the spring semester of 2019. After completing common theory courses, they were divided into two groups randomly for practice courses, which consisted of two modules: Lecture and Hands-on. Lecture included case-based learning while Hands-on included pictures reading. Each group followed different sequence of modules. There were assessments of ultrasound theory, practice or the combination of both before, during and after practice courses.Results:The theory and practice ability of each group improved significantly after practice courses ( P < 0.05). Moreover, the group whose Hands-on module preceded Lecture module got the higher scores in the evaluation of the combined ability of theory and practice ( P < 0.05). Conclusion:The theory was as important as the practice during the clerkship of ultrasonography. The clinical practical teaching pattern that Hands-on precedes Lecture has achieved better teaching effects.

Objective To investigate the effect of electroacupuncture at points Xiaohai and Xiajuxu on the expressions of tumour necrosis factor-α (TNF-α) and choline acetyltransferase (ChAT) in serum and nicotinic acetylcholine receptorα 7 (α 7 nAchR) in duodenal tissues in a rat model of duodenal ulcer (DU) and preliminarily explore the relative specificity of He-Sea point in “treating visceral diseases with He-Sea point”.Methods Forty healthy SD rats were randomized into blank (A), model (B), Xiaohai (C) and Xiajuxu (D) groups, 10 rats each. A rat model of DU was made by subcutaneous injection of 10% cysteamine hydrochloride at the right buttock. After successful model making, group C was given electroacupuncture at point Xiaohai and group D, at point Xiajuxu. Duodenal tissue ulcer was macroscopically observed and scored in every group of rats. Rat serum expression of TNF-α was determined by double antibody sandwich enzyme-linked immunosorbent assay (ELISA); rat serum expression of ChAT, by ultraviolet spectrophotometry & colorimetry; rat duodenal expression ofα7 nAchR, by Western blot.Results After model making, the duodenal ulcer score was significantly higher in groups B, C and D than in group A (allP<0.01) and significantly lower in groups C and D than in group B (bothP<0.01) and in group D than in group C (P<0.01). TNF-α expression was significantly higher in group B than in group A (P<0.01) and significantly lower in groups C and D than in group B (bothP<0.01) and in group D than in group C (P<0.01). ChAT expression tended to increase in group C compared with group B but there was no statistically significant difference (P>0.05) and was significantly higher in group D than in group B (P<0.01) or C (P<0.05).α7 nAchR expression was significantly higher in groups C and D than in group B (bothP<0.01). There was a positive correlation between ChAT andα7 nAchR expressions in every group (r=0.444,P=0.007).Conclusions Electroacupuncture at both points Xiaohai and Xiajuxu can reduce the duodenal ulcer score and serum TNF-α expression and increase serum ChAT and duodenalα7 nAchR expressions in DU rats. The results show that the therapeutic effect of electroacupuncture on duodenal ulcer may be produced by regulating TNF-α. Its mechanism may be activating cholinergic anti-inflammatory pathway to produce an anti-inflammatory effect. The effect being better in group D than in group C suggests that Xiajuxu has the relative specificity.