ObjectiveGastric hemorrhage is one of the most common and life-threatening emergencies of the upper digestive tract. Early identification and continuous monitoring are essential for reducing rebleeding rates and mortality, particularly within the critical early hours after onset. Although endoscopy and radiological imaging can accurately localize bleeding sites, these approaches are invasive, resource-intensive, and unsuitable for continuous bedside monitoring. Electrical impedance tomography (EIT), as a noninvasive and radiation-free functional imaging technique, offers real-time visualization of conductivity distribution and has the potential for detecting intragastric bleeding based on the electrical contrast between blood and surrounding gastric tissues. In this study, a three-dimensional gastric EIT (3D-gEIT) framework is proposed to achieve noninvasive, real-time, and dynamic monitoring of gastric hemorrhage, with emphasis on spatial localization and quantitative volume assessment. MethodsA three-dimensional upper-abdominal simulation model incorporating the stomach, gastric wall, gastric contents, and surrounding tissues was established. Three electrode configurations, namely the dual layer ring, the four layer staggered ring, and the opposed dual plane array, were designed and systematically compared to evaluate their influence on depth sensitivity and spatial resolution. Based on the Tikhonov-Noser hybrid regularization scheme, a region-clustering constraint was introduced to develop the TK-Noser-RCC algorithm. This approach aggregates spatially adjacent elements with similar conductivity variations, thereby enhancing structural continuity and suppressing isolated noise artifacts. To validate the proposed framework, an upper-abdominal physical phantom was constructed using agar to simulate background tissue conductivity. Hemispherical high-conductivity inclusions with volumes ranging from 10 ml to 50 ml were attached to the inner gastric wall to mimic localized bleeding under different gastric filling states. Boundary voltages were acquired under a 120 kHz excitation current and reconstructed using the TK-Noser-RCC algorithm. Furthermore, an in vivo animal experiment was performed using a porcine model with adult-scale abdominal dimensions. A total of 100 ml of autologous blood was injected incrementally into the stomach to simulate progressive gastric hemorrhage, and time-difference EIT reconstruction was conducted at each injection stage to assess the dynamic system response under physiological conditions. ResultsSimulation results demonstrated that the opposed dual-plane electrode array achieved superior depth sensitivity distribution and spatial resolution. For a 40 ml hemorrhage model, the average ICC and SSIM improved by 55.9% and 38.8% compared with the dual-layer ring configuration, and by 64.0% and 39.5% compared with the four-layer staggered configuration. The proposed region-clustering constraint significantly enhanced reconstruction stability. Under added Gaussian noise of 40 dB and 30 dB, ICC values remained approximately 0.85, indicating effective artifact suppression and preservation of boundary integrity. In physical phantom experiments, reconstructed hemorrhage volumes increased approximately linearly with the preset hemispherical volumes, and the reconstructed high-conductivity regions closely matched the actual bleeding locations. Both empty-stomach and full-stomach conditions were evaluated, demonstrating that the opposed dual-plane configuration maintained stable imaging performance across varying gastric contents. In the animal experiment, reconstructed low-impedance regions expanded progressively with increasing injected blood volume. The spatial localization of the hemorrhage remained stable throughout the procedure, and no significant artifacts were observed. Quantitative analysis showed that reconstructed volume and average conductivity variation exhibited an approximately linear growth trend with injected blood volume, confirming the sensitivity of the system to dynamic intragastric conductivity changes. ConclusionThe proposed 3D-gEIT framework enables quantitative reconstruction of gastric hemorrhage volume and spatial distribution with improved depth sensitivity, structural continuity, and noise robustness compared with conventional EIT approaches. By integrating optimized electrode configuration and a region-clustering-constrained reconstruction algorithm, the system provides stable dynamic monitoring under both controlled phantom conditions and in vivo physiological environments. This method offers a noninvasive, real-time, and low-cost imaging strategy for early diagnosis, postoperative monitoring, and bedside surveillance of gastric bleeding.

Based on LI Gao's theory of "heavy obstruction" and "blockage of the nine orifices"， this paper proposes the pathological concept of "heavy obstruction and orifice blockage". It is suggested that the core pathogenesis of functional constipation （FC） lies in simultaneous sinking of spleen and lung， together with accumulation and obstruction of dampness and turbidity， resulting in impaired movement of intestinal qi. Within this framework， spleen deficiency with sinking of dampness is considered as the primary pathological mechanism of outlet obstructive constipation （OOC）， while sinking of lung qi is regarded as the key mechanism underlying slow transit constipation （STC）. When both pathological mechanisms coexist， mixed constipation （MC） develops. Guided by this theory， FC is classified into three patterns for syndrome-based treatment. OOC is treated by promoting bowel movement， descending turbid pathogens， and opening the orifices to restore function， with self-formulated Shengxian Tongqiao Decoction （升陷通窍汤）. STC is treated by diffusing lung qi， regulating spleen function， raising sinking qi， and promoting transportation， with self-formulated Xuanfei Yunpi Decoction （宣肺运脾汤）. MC is treated by regulating lung and spleen function， simultaneously raising clear qi and descending turbidity， with self-formulated Xuanyun Tongqiao Decoction （宣运通窍汤）. In clinical practice， modifications should be made according to accompanying syndromes and individual conditions.

Based on LI Gao's theory of "heavy obstruction" and "blockage of the nine orifices"， this paper proposes the pathological concept of "heavy obstruction and orifice blockage". It is suggested that the core pathogenesis of functional constipation （FC） lies in simultaneous sinking of spleen and lung， together with accumulation and obstruction of dampness and turbidity， resulting in impaired movement of intestinal qi. Within this framework， spleen deficiency with sinking of dampness is considered as the primary pathological mechanism of outlet obstructive constipation （OOC）， while sinking of lung qi is regarded as the key mechanism underlying slow transit constipation （STC）. When both pathological mechanisms coexist， mixed constipation （MC） develops. Guided by this theory， FC is classified into three patterns for syndrome-based treatment. OOC is treated by promoting bowel movement， descending turbid pathogens， and opening the orifices to restore function， with self-formulated Shengxian Tongqiao Decoction （升陷通窍汤）. STC is treated by diffusing lung qi， regulating spleen function， raising sinking qi， and promoting transportation， with self-formulated Xuanfei Yunpi Decoction （宣肺运脾汤）. MC is treated by regulating lung and spleen function， simultaneously raising clear qi and descending turbidity， with self-formulated Xuanyun Tongqiao Decoction （宣运通窍汤）. In clinical practice， modifications should be made according to accompanying syndromes and individual conditions.

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective To propose a brain electrical phase prediction method based on long short-term memory network(LSTM)to improve the accuracy and robustness of phase synchronization prediction in transcranial magnetic stimulation(TMS).Methods First,an LSTM consisting of an input layer,an LSTM layer,an ReLU activation layer,a fully connected layer and a regression layer was constructed to capture the EEG signal features through the synergistic action of input gates,forgetting gates and output gates.Second,eye-open resting-state EEG data from 30 healthy subjects were trained using the LSTM to obtain a predictive model for EEG signal and EEG phase prediction.Finally,the LSTM method and the traditional autoregressive(AR)method were compared in terms of the phase prediction errors at the overall and individual levels and the prediction performance for peaks and troughs.A regression model was used to explore the relationships between instantaneous EEG amplitude,signal-to-noise ratio and phase prediction error with the LSTM method.Results The LSTM method achieved a total phase prediction error of 0.04°±5.69°,which was lower than that of the traditional AR method(-3.36°±51.13°).For each subject,the LSTM method demonstrated superior phase prediction accuracy compared to the traditional AR method(P＜0.001).The accuracy for predicting peaks(troughs)by the LSTM method(about 89％)was higher than that by the traditional AR method(about 10％).Unlike the traditional AR method,the LSTM method didnot result in linear relationships between instantaneous EEG amplitude,signal-to-noise ratio and phase prediction error,with Pvalues being 0.58 and 0.18,respectively.Conclusion The LSTM-based brain electrical phase prediction method shows high accuracy and robustness when used for EEG phase-synchronized TMS.[Chinese Medical Equipment Journal,2025,46(3):1-8]

Aim To investigate the expression of or-ganic anion transporting polypeptide 4C1(Oatp4c1)-P-glycoprotein(P-gp)in the kidneys of obese mice in-duced by high-fat diet(HFD),and its impact on the pharmacokinetic changes of digoxin.Methods C57BL/6 mice were randomly divided into the Chow group and the HFD group.Body weight and blood glu-cose were recorded weekly.After successful model es-tablishment,digoxin was intraperitoneally injected,and blood was collected at different time points.Part of the blood samples was used for LC-MS/MS detection,and the other part was used for the detection of other bio-chemical indicators.After 16 weeks,the organs were removed and weighed.HE and immunohistochemical staining was used to observe the renal pathology and the expression of Villin,a marker of proximal tubules.Western blot and qPCR were combined to detect the expression of Villin,Oatp4c1 and P-gp.Results In the HFD group,body weight and blood glucose in-creased significantly.The blood concentration of digox-in rose,the area under the curve increased,and the half-life was prolonged.The proximal tubular epithelial cells shed,and the protein expression of Villin,Oatp4c1 and P-gp decreased significantly.Conclu-sions The down-regulation of Oatp4c1-P-gp expres-sion in the kidneys of HFD mice leads to an increase in the blood concentration of digoxin and a decrease in re-nal clearance.

Objective To propose a preventive maintenance strategy of the heating,ventilation and air-conditioning(HVAC)system in pharmacy intravenous admixture services(PIVAS)based on the reliability centered maintenance(RCM)method so as to provide references for PIVAS equipment maintenance.Methods Firstly,a HVAC system RCM review team was formed,and the failure modes and impacts of important functional components of the equipment were analyzed to clarify the consequences of the failure of each functional component under the premise of ensuring the safety and integrity of the equipment and with the goal of minimizing the loss of maintenance downtime and the consumption of maintenance resources.Secondly,with a standardized logical decision-making procedure the preventive maintenance strategy was determined and implemented based on the consequences of functional failure.Finally,statistical analyses were carried out on such equipment indicators as performance parameter qualification rate,failure rate and maintenance cost before and after the RCM method-based strategy was executed,in order to evaluate the efficacy of the strategy.Results The RCM method-based preventive maintenance strategy had the performance qualification rate increased from 97.47%to 99.06%(χ2=24.139,P<0.01),the failure rate decreased from 0.24%to 0.03%(χ2=13.519,P<0.01)and the maintenance cost reduced by 11.5%,from RMB 134,200 to 118,700.Conclusion The RCM method-based preventive maintenance strategy provides reliable equipment for PIVAS and lowers the maintenance cost effectively,and references are given for the development of automated and intelligent equipment maintenance strategies for PIVAS.[Chinese Medical Equipment Journal,2025,46(10):78-83]

Aim To explore the effect of FTO on adria-mycin resistance in triple-negative breast cancer through the Wnt/β-catenin signaling pathway and to reveal the underlying mechanism.Methods The MDA-MB-231/ADR drug-resistant cell line was constructed using a method of gradually increasing adriamycin concentra-tion with intermittent induction.The half-inhibitory concentration(IC50)of adriamycin for MDA-MB-231 and MDA-MB-231/ADR cells and the expression of FTO were compared.After knocking down FTO in MDA-MB-231/ADR cells,CCK-8,qRT-PCR,colony formation assay,transwell,flow cytometry,and Western blot were used to assess the changes in the IC50 of adri-amycin,cell proliferation,migration,invasion,apopto-sis,and the expression of related proteins.Results FTO was highly expressed in MDA-MB-231/ADR cells.After FTO knockdown,the IC50 value of adriamy-cin in MDA-MB-231/ADR cells decreased,and the a-bilities of proliferation,migration and invasion were weakened.In the FTO knockdown group,the expres-sion levels of Bax,cleaved-caspase3,GSK-3 β proteins and the apoptosis rate significantly increased,while the expression levels of Bcl-2,Wnt5a,β-catenin,c-myc,cyclin D1,and P-gp proteins decreased.Conclusion FTO may inhibit the apoptosis of MDA-MB-231/ADR cells through the Wnt/β-catenin signaling pathway,al-ter P-gp expression,and thereby enhance the resistance of MDA-MB-231/ADR cells to adriamycin.

Monoamine neurotransmitters mainly include serotonin,dopamine,epinephrine,and norepinephrine.They play an indispensable regulatory role in key physiological activities such as emotion,sleep,and memory within the central nervous system.Precise detection of these neurotransmitters holds great significance in the field of neuroscience research.Detection methods for monoamine neurotransmitters encompass high-performance liquid chromatography,mass spectrometry,capillary electrophoresis,fluorescence spectroscopy,and electrochemical methods,etc.Compared with other methods,electrochemical methods offer advantages such as high sensitivity,good selectivity,low cost,strong portability,convenient operation,and capability for in vivo real-time detection.This article reviewed recent research progress in electrochemical detection of monoamine neurotransmitters,focusing on a retrospective and summary from three aspects:sensor electrode materials,detection of various monoamine neurotransmitters,and in vivo real-time analysis.Furthermore,the future development of electrochemical sensors for monoamine neurotransmitters was prospected.