1.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.
2.An Attention-weighted Tri-modal Ultrasound Network (TUS-Net) for Screening of Atypical Hepatocellular Carcinoma From LR-M Liver Nodules
He-Chong ZHANG ; Liang-Hui HUANG ; Xue-Hua WANG ; Shang-Lin JIANG ; Ying-Ying CHEN ; Ya-Guang ZENG ; Wei ZHENG
Progress in Biochemistry and Biophysics 2026;53(5):1485-1498
ObjectiveDiscriminating atypical hepatocellular carcinoma (HCC) from other malignancies in liver nodules classified as Liver Imaging Reporting and Data System category M (LR-M) remains a significant diagnostic challenge on conventional ultrasound examination. The LR-M category, originally intended to capture non-HCC malignancies, paradoxically contains up to 63% of atypical HCCs that deviate from classic enhancement patterns, leading to potential misdiagnosis and suboptimal treatment planning. While deep learning has shown promise in HCC diagnosis, most existing models rely exclusively on single-modality ultrasound, overlooking the diagnostic benefits of integrating complementary information from multiple imaging sources. To address this gap, we propose a novel attention-weighted tri-modal ultrasound network (TUS-Net) that integrates contrast-enhanced ultrasound (CEUS), B-mode ultrasound (BUS), and time-intensity curves (TICs) to improve diagnostic accuracy for these clinically challenging lesions. MethodsOur framework incorporates a three-dimensional convolutional neural network (C3D) backbone to extract spatiotemporal features from CEUS videos, capturing dynamic vascular patterns critical for lesion characterization. To effectively fuse complementary modalities, we introduce a dual-channel feature fusion module (DCFFM) that adaptively combines features from CEUS and BUS through channel-wise attention mechanisms, allowing the model to dynamically weigh the contribution of each modality based on diagnostic relevance. Additionally, we propose a temporal intensity feature fusion module (TIFFM) that leverages quantitative hemodynamic information from TICs to guide the model’s attention toward diagnostically critical temporal phases, such as arterial wash-in and portal venous washout. The model is further enhanced by automated lesion localization using YOLOX and class activation mapping for interpretability, ensuring that predictions align with clinically meaningful imaging features. ResultsEvaluated on a tri-modal ultrasound dataset comprising 161 patients with pathologically confirmed LR-M nodules (131 atypical HCC and 30 non-HCC malignancies), our model achieved an accuracy of 86.83%, a sensitivity of 92.50%, a specificity of 75.50%, and an AUC of 89.32% in screening atypical HCC. Compared to single-modality baselines, TUS-Net demonstrated superior specificity, a clinically critical metric given the higher risk associated with misclassifying non-HCC malignancies. Ablation studies confirmed the contribution of each module, with the full model outperforming both standard C3D and 3D ResNet backbones integrated with attention mechanisms. A reader study involving junior and senior radiologists further validated the clinical utility of AI assistance, showing consistent improvements in specificity and inter-reader consistency, particularly for less experienced clinicians. ConclusionThese results surpass existing benchmark models and demonstrate the potential of our approach to enhance diagnostic precision in clinically specific cases. By intelligently fusing multi-modal ultrasound data with attention-guided mechanisms, TUS-Net offers a reliable and interpretable tool that holds promise for improving the non-invasive diagnosis of atypical HCC in challenging LR-M liver nodules.
3.An Attention-weighted Tri-modal Ultrasound Network (TUS-Net) for Screening of Atypical Hepatocellular Carcinoma From LR-M Liver Nodules
He-Chong ZHANG ; Liang-Hui HUANG ; Xue-Hua WANG ; Shang-Lin JIANG ; Ying-Ying CHEN ; Ya-Guang ZENG ; Wei ZHENG
Progress in Biochemistry and Biophysics 2026;53(5):1485-1498
ObjectiveDiscriminating atypical hepatocellular carcinoma (HCC) from other malignancies in liver nodules classified as Liver Imaging Reporting and Data System category M (LR-M) remains a significant diagnostic challenge on conventional ultrasound examination. The LR-M category, originally intended to capture non-HCC malignancies, paradoxically contains up to 63% of atypical HCCs that deviate from classic enhancement patterns, leading to potential misdiagnosis and suboptimal treatment planning. While deep learning has shown promise in HCC diagnosis, most existing models rely exclusively on single-modality ultrasound, overlooking the diagnostic benefits of integrating complementary information from multiple imaging sources. To address this gap, we propose a novel attention-weighted tri-modal ultrasound network (TUS-Net) that integrates contrast-enhanced ultrasound (CEUS), B-mode ultrasound (BUS), and time-intensity curves (TICs) to improve diagnostic accuracy for these clinically challenging lesions. MethodsOur framework incorporates a three-dimensional convolutional neural network (C3D) backbone to extract spatiotemporal features from CEUS videos, capturing dynamic vascular patterns critical for lesion characterization. To effectively fuse complementary modalities, we introduce a dual-channel feature fusion module (DCFFM) that adaptively combines features from CEUS and BUS through channel-wise attention mechanisms, allowing the model to dynamically weigh the contribution of each modality based on diagnostic relevance. Additionally, we propose a temporal intensity feature fusion module (TIFFM) that leverages quantitative hemodynamic information from TICs to guide the model’s attention toward diagnostically critical temporal phases, such as arterial wash-in and portal venous washout. The model is further enhanced by automated lesion localization using YOLOX and class activation mapping for interpretability, ensuring that predictions align with clinically meaningful imaging features. ResultsEvaluated on a tri-modal ultrasound dataset comprising 161 patients with pathologically confirmed LR-M nodules (131 atypical HCC and 30 non-HCC malignancies), our model achieved an accuracy of 86.83%, a sensitivity of 92.50%, a specificity of 75.50%, and an AUC of 89.32% in screening atypical HCC. Compared to single-modality baselines, TUS-Net demonstrated superior specificity, a clinically critical metric given the higher risk associated with misclassifying non-HCC malignancies. Ablation studies confirmed the contribution of each module, with the full model outperforming both standard C3D and 3D ResNet backbones integrated with attention mechanisms. A reader study involving junior and senior radiologists further validated the clinical utility of AI assistance, showing consistent improvements in specificity and inter-reader consistency, particularly for less experienced clinicians. ConclusionThese results surpass existing benchmark models and demonstrate the potential of our approach to enhance diagnostic precision in clinically specific cases. By intelligently fusing multi-modal ultrasound data with attention-guided mechanisms, TUS-Net offers a reliable and interpretable tool that holds promise for improving the non-invasive diagnosis of atypical HCC in challenging LR-M liver nodules.
4.Microchannel-based Electrochemiluminescence Sensor for Tetracycline Detection Using Luminol/Hydrogen Peroxide as Reporter System
Shao-Kun HUANG ; Xiu-Lin XIE ; Hua-Bin CAI ; Yan-Ling HUANG ; Yue LIN ; Zhen-Yu LIN
Chinese Journal of Analytical Chemistry 2025;53(3):356-363
A microchannel-based electrochemiluminescence(ECL)sensor was developed for detection of tetracycline(TC)utilizing luminol/H2O2 as ECL reporting system.The low excitation potential of luminol/H2O2 effectively mitigated the impact of clamping voltage,thereby enhancing the detection performance of the microchannel-based ECL sensor.The microchannel modified with TC aptamer selectively recognized and captured target TC.The positively charged TC reduced the surface charge density within the microchannel,thereby increasing the ionic current in the microchannel,leading to change of ECL signal of system.The experimental conditions such as electrolyte concentration,TC-aptamer concentration,and reaction time between TC and TC-aptamer were optimized.Under optimal conditions,the difference of ECL signal in the absence and presence of TC(?ECL)exhibited a good linear relationship with TC concentration in the range from 1.00 ng/mL to 200 ng/mL,with a detection limit as low as 0.69 ng/mL.The sensor had good selectivity and was successfully used in detection of TC in milk samples.
5.Research Progress on Electrochemical Sensing Techniques for Detection of Telomerase Activity
Hai-Tang YANG ; Peng-Hua SHU ; Wen-Lin LIU ; Wen-Bo MA ; Zi-Jun YANG ; Zhi-Feng DENG ; Xin-Yun ZHANG ; Wei WEI
Chinese Journal of Analytical Chemistry 2025;53(6):864-874
The telomere structure in the cell nucleus is crucial for maintaining the stability and functions of chromosomes.Telomerase is a ribonucleoprotein reverse transcriptase,which catalyzes the elongation of telomeres using its own RNA as a template,thereby counteracting the shortening of telomeres caused by chromosome replication and cell division.Due to its overexpression in over 85%of malignant tumor cells,telomerase has emerged as a highly promising biomarker and a novel target for cancer therapy.In recent years,given the importance of precise quantification of telomerase activity in guiding medical diagnosis and treatment strategies,researchers have developed various high-performance telomerase detection techniques.Among these,electrochemical biosensing technique has cause much attention due to its high sensitivity,operational convenience,rapid response,and ease of miniaturization.This paper focused on the latest advances in electrochemical sensing technique for detection of telomerase activity,aiming to provide inspiration for designing novel telomerase activity detection strategies by elucidating three unique properties of telomerase primer extension products.
6.Construction and Application of"On-Off-On"Fluorescence Sensor for Chlorpromazine Hydrochloride Based on Near Infrared Carbon Quantum Dots
Yu LIN ; Feng TAN ; Yu-Hua SHEN ; Li-Qin ZHU ; Pei-Yao YAN ; Jin-Tao PAN ; Kai-Shun LIU
Chinese Journal of Analytical Chemistry 2025;53(6):934-943
In this work,near infrared carbon quantum dots(NIR-CDs)were synthesized by hydrothermal method using biomass material Clausena lansium leaves.The synthesized NIR-CDs emitted maximum fluorescence signal at 677 nm,which was independent of excitation wavelength.The characterization results showed that there were abundant groups on the surface of NIR-CDs.Pd2+could form non-fluorescent compounds with the surface groups of NIR-CDs,resulting in fluorescence quenching(Fluorescence signal was denoted as F0).Because chlorpromazine hydrochloride(CPZ)parent nucleus contained unoxidized S atom,CPZ could form stable colored complex with Pd2+under acidic conditions.In the presence of CPZ,Pd2+dissociated from the surface of NIR-CDs and bonded with CPZ,so that the fluorescence signal could be restored(Fluorescence signal was denoted as F).An"on-off-on"fluorescence sensor was thus constructed.The fluorescence signal recovery value of NIR-CDs(△F=F-F0)showed a good linear relationship with the concentration of CPZ in the range of 5.68-28.43 μg/mL,and the detection limit(3σ)was 0.078 μg/mL.The sensor was applied to determination of CPZ in pharmaceutical preparations,and the recoveries were 94%-106%.The developed fluorescence sensor was expected to be used in quality control of actual pharmaceutical preparations.
7.Reliable Extraction of Seawater Nd and Hf Isotope Compositions from Fe-Mn Oxyhydroxide Fraction of Marine Sediments in the Arctic Ocean
Ying ZHANG ; Lin-Sen DONG ; Hong-Min WANG ; Xiao-Jing WANG ; Lian-Hua HE ; Yan-Guang LIU ; Ji-Hua LIU
Chinese Journal of Analytical Chemistry 2025;53(8):1380-1390
Combined seawater Hf and Nd isotope compositions have been applied as reliable tracers of water mass mixing and weathering input changes.The establishment of standardized synchronous extraction methods for Fe-Mn oxyhydroxide in sediments,which serve as effective carriers for isotopic signals of ancient seawater,is a prerequisite and key for paleoceanography research.The research material of this study was the surface sediments of the Western Arctic Ocean obtained from China's 7th Arctic Scientific Expedition,and a reliable simultaneous Nd-Hf isotope extraction method in Fe-Mn oxyhydroxide fraction was established through systematic optimization of pretreatment procedures and key extraction parameters.This research focused on analyzing the effects of pretreatment(Milli-Q water pre-wash)and key extraction parameters(leaching time,solution/solid ratios,concentration of EDTA-2Na,and concentration of mixed solution of hydroxyamine hydrochloride(HH)and acetic acid(HAc))on element extraction efficiency and isotopic composition.The experimental results indicated that the Milli-Q water pre-wash was not necessary,Fe-Mn oxyhydroxide extraction could be directly performed.Nd extraction amount in Fe-Mn oxyhydroxide fraction was not sensitive to changes in extraction conditions,while the Hf extraction amount was significantly affected by leaching time,solution/solid ratios and concentration of EDTA-2Na.The optimal conditions for synchronously extracting Nd-Hf isotopes were as follows:adding 20 mL of a mixed solution of 0.005 mol/L HH+1.5%HAc+0.03 mol/L EDTA-2Na per gram of sample,and reaction at room temperature for 3 h under shaking.Through systematic verification of 87Sr/86Sr ratio,εNd value,εHf value,Al/Nd ratio and Al/Hf ratio,it was confirmed that this method could effectively avoid interferences from residual components and accurately obtain Nd-Hf isotope signals of ancient seawater preserved in sediments.The standardized method established in this work provided reliable technical support for reconstructing water mass mixing between the Arctic,North Atlantic,and North Pacific Oceans and riverine input histories.It also provided important reference for the extraction methods of Nd and Hf isotopes from marine sources in sediments from other sea areas around the world.
8.Etiological composition and clinical analysis of hypertension in 74 infants
Chen LING ; Zhi CHEN ; Hejia ZHANG ; Lei LEI ; Yue XI ; Suyun QIAN ; Lin HUA ; Xiaorong LIU
International Journal of Pediatrics 2025;52(2):127-131
Objective:To analyze the etiological composition and clinical characteristics of infant hypertension,and provide reference for its diagnosis and treatment.Methods:This is a retrospective case-control study.Retrospective investigation and analysis were conducted on the clinical data of infants discharged from Beijing Children's Hospital Affiliated to Capital Medical University with a diagnosis of "hypertension" from June 1,2016 to September 30,2021,including clinical manifestations,auxiliary examinations,treatment plans,and prognosis.Results:A total of 74 eligible children were collected,including 42 male infants(56.8%)and 32 female infants(43.2%).A total of 67 cases(90.5%)had clear secondary factors,including 35 cases of kidney disease(47.3%),12 cases of connective tissue disease(16.2%),and 9 cases of hematological tumor disease(12.2%).At the beginning of the disease,cardiac ultrasound showed that 54 cases(73.0%)had ventricular wall thickening,including mild thickening in 31 cases(57.4%),moderate thickening in 11 cases(20.3%),and severe thickening in 12 cases(22.2%).After grouping by etiology,the incidence of proteinuria and severe hypertension in the renal hypertension group,as well as those receiving multiple antihypertensive drugs,was significantly higher than that in the non-renal hypertension group( χ 2=28.493, P<0.001; χ 2=17.283, P<0.001; χ 2=17.358, P<0.001);Renal disease was risk factor for severe hypertension in infants according to univariate and multivariate logistic regression analysis respectively( OR=11.176,95% CI:2.882~43.339, P<0.001; OR=11.669,95% CI:2.921~46.624, P<0.001).Thirty-one children had follow-up records for 6 months or more,and 13(41.9%)still required antihypertensive treatment,of whom 26(83.9%)were no longer recorded as having elevated blood pressure. Conclusion:Infant hypertension is mainly secondary,with a high proportion of renal factors and predisposition to severe hypertension,which requires multiple antihypertensive drugs for control.Active antihypertensive treatment and removal of secondary factors during the acute phase are helpful for controlling hypertension in infants,but further research is needed on treatment options and long-term prognosis.
9.Textual study on clinical application of Schisandrae Chinensis Fructus from the perspective of various dynasties of herbs and prescription books
Yunya LIU ; Huijuan XIE ; Lujie LIN ; Zhikun HE ; Hua LI ; Min YANG ; Bin YANG
International Journal of Traditional Chinese Medicine 2025;47(3):298-305
Various dynasties of herbs and prescription books recorded the specifications, processing, and clinical application of Schisandrae Chinensis Fructus. The clinical application of Schisandrae Chinensis Fructus mainly focuses on astringency, tonifying qi and generating fluids, nourishing the kidneys and calming the heart. There have been few reports on the exploration on textual study on other functions and usage precautions of Schisandrae Chinensis Fructus; at present, the classic prescriptions containing Schisandrae Chinensis Fructus do not clearly indicate their specific specifications and processing in the prescription composition. Textual study has found that different processed products of Schisandrae Chinensis Fructus have different clinical therapeutic effects. For raw use, it is more suitable to use light agents to bring adversely risen qi downward, steam to produce light agents to increase transparency, honey to produce leveling agents is better for moistening the lungs and nourishing yin, wine honey to produce leveling agents can supplement deficiency and promote blood circulation, wine to produce heavy agents can strengthen acid absorption. It is suggested further in-depth research on steamed products, honey products, and honey wine products to broaden clinical application options and improve the accuracy of clinical medication. The clinical application of Schisandrae Chinensis Fructus has different emphases and evolution in different dynasties. In the Tang Dynasty, Schisandrae Chinensis Fructus could reduce the qi of the upper, middle, and lower energizers, and eliminate deficiency heat; during the Five Dynasties period, Schisandrae Chinensis Fructus could nourish qi, improve eyesight, warm the middle, and bring adversely risen qi downward; During the Jin and Yuan dynasties, Schisandrae Chinensis Fructus was used to warm water and treat cholera, as well as to improve muscle function; in the Ming Dynasty, Schisandrae Chinensis Fructus was proposed to reduce qi and strengthen yin, treating the critical condition of yin and yang deficiency; during the Qing Dynasty, Schisandrae Chinensis Fructus could prevent summer heat, and external application to sores could astringent and invigorate the muscles. Schisandrae Sphenantherae Fructus has records of dispersing phlegm and fire, and dispelling wind pathogens. This article reviewed the relevant records of Schisandrae Chinensis Fructus in traditional Chinese herbs and prescriptions throughout history, summarized the efficacy characteristics of Schisandrae Chinensis Fructus under different processing methods, clinical applications under historical evolution, and main contraindications for use, proposed recommendations for the application of Schisandrae Chinensis Fructus in classic and commonly used prescriptions, which can provide scientific basis for the precise selection of different specifications and processed products of Schisandrae Chinensis Fructus and Schisandrae Sphenantherae Fructus, as well as scientific guidance for their rational application in drug development.
10.Advances in role and mechanism of traditional Chinese medicine active ingredients in regulating balance of Th1/Th2 and Th17/Treg immune responses in asthma patients.
Ya-Sheng DENG ; Lan-Hua XI ; Yan-Ping FAN ; Wen-Yue LI ; Yong-Hui LIU ; Zhao-Bing NI ; Ming-Chan WEI ; Jiang LIN
China Journal of Chinese Materia Medica 2025;50(4):1000-1021
Asthma is a chronic inflammatory disease involving multiple inflammatory cells and cytokines. Its pathogenesis is complex, involving various cells and cytokines. Traditional Chinese medicine(TCM) theory suggests that the pathogenesis of asthma is closely related to the dysfunction of internal organs such as the lungs, spleen, and kidneys. In contrast, modern immunological studies have revealed the central role of T helper 1(Th1)/T helper 2(Th2) and T helper 17(Th17)/regulatory T(Treg) cellular immune imbalance in the pathogenesis of asthma. Th1/Th2 imbalance is manifested as hyperfunction of Th2 cells, which promotes the synthesis of immunoglobulin E(IgE) and the activation of eosinophil granulocytes, leading to airway hyperresponsiveness and inflammation.Meanwhile, Th17/Treg imbalance exacerbates the inflammatory response in the airways, further contributing to asthma pathology.Currently, therapeutic strategies for asthma are actively exploring potential targets for regulating the balance of Th1/Th2 and Th17/Treg immune responses. These targets include cytokines, transcription factors, key proteins, and non-coding RNAs. Precisely regulating the expression and function of these targets can effectively modulate the activation and differentiation of immune cells. In recent years,traditional Chinese medicine active ingredients have shown unique potential and prospects in the field of asthma treatment. Based on this, the present study systematically summarizes the efficacy and specific mechanisms of TCM active ingredients in treating asthma by regulating Th1/Th2 and Th17/Treg immune balance through literature review and analysis. These active ingredients, including flavonoids, terpenoids, polysaccharides, alkaloids, and phenolic acids, exert their effects through various mechanisms, such as inhibiting the activation of inflammatory cells, reducing the release of cytokines, and promoting the normal differentiation of immune cells. This study aims to provide a solid foundation for the widespread application and in-depth development of TCM in asthma treatment and to offer new ideas for clinical research and drug development of asthma.
Asthma/genetics*
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Humans
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Drugs, Chinese Herbal/chemistry*
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Th2 Cells/drug effects*
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Th17 Cells/drug effects*
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T-Lymphocytes, Regulatory/drug effects*
;
Th1 Cells/drug effects*
;
Animals
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Cytokines/immunology*
;
Medicine, Chinese Traditional

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