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.Preliminary Outcomes of Endoscopic Spine Surgery Adoption at a Singapore Tertiary Hospital: A Multisurgeon Experience
John Wen Cong THNG ; Nicholas WONG ; Kai Lin LEE ; Wu Jie TOH ; Haobin CHEN ; Ghim Hoe NEO ; Yilun HUANG
Journal of Minimally Invasive Spine Surgery and Technique 2026;11(1):95-104
Objective:
This study characterizes the demographic and clinical profiles of patients undergoing unilateral biportal endoscopic spine surgery (UBE ESS) for lumbar decompression/discectomy at a tertiary hospital in Singapore. It examines service implementation across multiple senior surgeons, evaluates preliminary clinical outcomes, and describes the learning curve observed during early adoption among surgeons already experienced in minimally invasive spine surgery, benchmarked against international standards. In the context of increasing global uptake of endoscopic techniques, this work provides evidence to inform institutional adoption and surgeon training. This analysis forms part of a multi-paper series comparing surgeon experience and patient outcomes between conventional minimally invasive approaches and UBE ESS for lumbar decompression/discectomy.
Methods:
We conducted a retrospective review of 111 patients who underwent UBE lumbar decompression/discectomy at a public tertiary hospital between October 2022 and April 2024. Data on patient demographics, comorbidities, presenting symptoms, operative details, and clinical outcomes, including visual analogue scale (VAS) scores and 36-Item Short Form Health Survey (SF-36) health domains, were analyzed using appropriate statistical methods.
Results:
The mean patient age was 56.8 years, with a slight female predominance (54.1%). Statistically significant improvements were observed in VAS scores for both back and leg pain (p<0.05), alongside significant gains in SF-36 domains including physical functioning, bodily pain, vitality, and social functioning. Operative times decreased progressively with increasing case volume, consistent with the presence of a procedural learning curve.
Conclusion
UBE ESS for lumbar decompression/discectomy is a safe and efficacious technique that can be successfully adopted by spinal surgeons with prior minimally invasive surgical experience. Operative time demonstrates a meaningful reduction once the initial learning curve has been overcome. ESS provides a reproducible option for the treatment of degenerative lumbar spine disease in the tertiary hospital setting in Singapore, with outcomes comparable to established international benchmarks. Future work will include long-term follow-up of this patient cohort and direct comparison with conventional minimally invasive techniques in subsequent studies.
3.Trends in Lumbar Spinal Decompression Surgery at a Single Tertiary Center: A Retrospective Review
Kai Lin LEE ; Dhivakaran GENGATHARAN ; John Wen Cong THNG ; Thanos SIVRIDIS ; Dickson CHAU ; Ghim Hoe NEO ; Haobin CHEN ; Ji Min LING ; Thomas Choo Heng TAN ; Yilun HUANG
Journal of Minimally Invasive Spine Surgery and Technique 2026;11(1):65-76
Objective:
Spinal stenosis and degenerative spinal disorders are increasingly prevalent and have a substantial impact on quality of life. Surgical decompression, performed using either open microscopic or endoscopic approaches, remains a cornerstone of management for these conditions. This study examines evolving trends in single-level lumbar spinal decompression procedures performed at a tertiary academic hospital in Singapore.
Methods:
A retrospective observational study was conducted involving 588 patients who underwent single-level spinal decompression between 2021 and 2024, including endoscopic spine surgery (ESS; n=364) and microdecompression (n=224). Primary outcome measures were changes in 36-Item Short Form Health Survey (SF-36) and visual analogue scale (VAS) scores at 3 months, 6 months, and 2 years postoperatively. Secondary outcomes included length of hospital stay, reoperation rates, and operative time. Patient demographics, spinal level and pathology characteristics, surgical techniques, and postoperative outcomes were analyzed. Difference-in-differences (DID) analysis was used to compare outcomes between the 2 groups.
Results:
Both groups demonstrated significant postoperative improvements in SF-36 and VAS scores. At 2 years, Short Form Health Survey physical function (SFPF) scores improved in the endoscopic group (mean difference [MD], 18.6; standard deviation [SD], 21.7; p=0.064) and in the open microscopic group (MD, 36.7; SD, 20.9; p=0.007), with a non-significant DID of -18.1 (p=0.155). No DID comparisons across SF-36 domains reached statistical significance. Mean operative time for endoscopic procedures decreased from 249 minutes in 2022 to 145 minutes in 2024, reflecting a procedural learning curve. Surgeons with higher endoscopic caseloads exhibited greater improvements in functional outcomes.
Conclusion
Both endoscopic and open microscopic decompression achieve comparable short- and long-term clinical outcomes. ESS provides similar effectiveness while being associated with shorter recovery periods and reduced hospital stay. Further research is warranted to identify factors contributing to incomplete symptom resolution or the need for revision surgery.
4.Clinical Efficacy of Tangning Tongluo Tablets for Nonproliferative Diabetic Retinopathy
Fuwen ZHANG ; Junguo DUAN ; Wen XIA ; Tiantian SUN ; Yuheng SHI ; Shicui MEI ; Xiangxia LUO ; Xing LI ; Yujie PAN ; Yong DENG ; Chuanlian RAN ; Hao CHEN ; Li PEI ; Shuyu YANG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(3):132-139
ObjectiveTo observe the clinical efficacy and safety of Tangning Tongluo tablets in the treatment of nonproliferative diabetic retinopathy (DR). MethodsFourteen research centers participated in this study, which spanned a time interval from September 2021 to May 2023. A total of 240 patients with nonproliferative DR were included and randomly assigned into an observation group (120 cases) and a control group (120 cases). The observation group was treated with Tangning Tongluo tablets, and the control group with calcium dobesilate capsules. Both groups were treated for 24 consecutive weeks. The vision, DR progression rate, retinal microhemangioma, hemorrhage area, exudation area, glycosylated hemoglobin (HbA1c) level, and TCM syndrome score were assessed before and after treatment, and the safety was observed. ResultsThe vision changed in both groups after treatment (P<0.05), and the observation group showed higher best corrected visual acuity (BCVA) than the control group (P<0.05). The DR progression was slow with similar rates in the two groups. The fundus hemorrhage area and exudation area did not change significantly after treatment in both groups, while the observation group outperformed the control group in reducing the fundus hemorrhage area and exudation area. There was no significant difference in the number of microhemangiomas between the two groups before treatment. After treatment, the number of microhemangiomas decreased in both the observation group (Z=-1.437, P<0.05) and the control group (Z=-2.238, P<0.05), and it showed no significant difference between the two groups. As the treatment time prolonged, the number of microhemangiomas gradually decreased in both groups. There was no significant difference in the HbA1c level between the two groups before treatment. After treatment, the decline in the HbA1c level showed no significant difference between the two groups. The TCM syndrome score did not have a statistically significant difference between the two groups before treatment. After treatment, neither the TCM syndrome score nor the response rate had significant difference between the two groups. With the extension of the treatment time, both groups showed amelioration of TCM syndrome compared with the baseline. ConclusionTangning Tongluo tablets are safe and effective in the treatment of nonproliferative DR, being capable of improving vision and reducing hemorrhage and exudation in the fundus.
5.Clinical Study on Yiqi Huoxue Prescription in the Treatment of Mild Cervical Spondylotic Myelopathy of Qi Deficiency and Blood Stasis Type
Siyuan RAO ; Yongpeng LIN ; Rui LIN ; Junbiao GUO ; Yong WEN ; Xiaoqiang DENG ; Jianbo ZENG ; Huimin WANG ; Bolai CHEN
Journal of Guangzhou University of Traditional Chinese Medicine 2025;42(2):309-314
Objective To investigate the clinical efficacy of Yiqi Huoxue Prescription(derived from Shengyu Decoction)in the treatment of mild cervical spondylotic myelopathy(CSM)with qi deficiency and blood stasis type.Methods A total of 128 patients with mild CSM of qi deficiency and blood stasis type who admitted to Guangdong Provincial Hospital of Chinese Medicine from January 2022 to January 2024 were randomly divided into the control group and the trial group according to the random number table method,with 64 cases in each group.The control group was treated with oral administration of Mecobalamin Tablets,and the trial group was treated with Yiqi Huoxue Prescription orally on the basis of treatment for the control group.The two groups were all treated for four weeks,and then were followed up for three months after the completion of treatment.The CSM scores of the Japanese Orthopedic Association(JOA)and the traditional Chinese medicine(TCM)syndrome scores in the two groups were observed before treatment,after two weeks of treatment,after four weeks of treatment,and three months after the completion of treatment.And then the clinical efficacy,progression of CSM and the incidence of adverse reactions of the two groups were evaluated.Results(1)During the trial,two cases in the control group and three cases in the trial group fell off,and eventually a total of 123 cases were included,62 cases in the control group and 61 cases in the trial group.(2)Three months after the completion of treatment,the total effective rate of the trial group was 93.44%(57/61)and that of the control group was 82.26%(51/62),and the intergroup comparison(tested by chi-square test)showed that the efficacy of the trial group was significantly superior to that of the control group,the difference being statistically significant(P<0.05).(3)After two and four weeks of treatment as well as three months after the completion of treatment,JOA scores in the two groups were increased compared with those before treatment(P<0.05),and JOA scores of the trial group at various time points mentioned above were higher than those of the control group,the difference being statistically significant(P<0.05).(4)After two and four weeks of treatment as well as three months after the completion of treatment,TCM syndrome scores in the two groups were decreased compared with those before treatment(P<0.05),and TCM syndrome scores of the trial group at various time points mentioned above were lower than those of the control group,the difference being statistically significant(P<0.05).(5)During the follow-up period,there was none case of significant aggravation or progression to moderate-severe illness in the two groups,and there were no adverse events such as allergies and gastrointestinal reactions.Conclusion Yiqi Huoxue Prescription exerts certain efficacy in treating patients with mild CSM of the qi deficiency and blood stasis type,and the treatment method is effective on improving the spinal cord function and symptoms of qi deficiency and blood stasis type,and slowing down the progression of disease in the patients,with high safety.
6.Downregulation of Talin1 inhibits migration of pulmonary arterial smooth muscle cells(PASMCs)induced by serum of rat models with HPS
Yang CHEN ; Jing WEN ; Lan SHI ; Yong YANG ; Bin YI ; Lin CHEN
Basic & Clinical Medicine 2025;45(11):1409-1414
Objective To evaluate the role of Talin1 in the migration of rat pulmonary artery smooth muscle cells(PASMCs)induced by the serum from rats with hepatopulmonary syndrome(HPS).Methods Twenty male Spra-gue-Dawley(SD)rats were used as HPS rat models by chronic common bile duct ligation,the serum was collected from abdominal aorta.PASMCs were seeded in 6-well and 24-well plates and randomly divided into control group and HPS group.The cells were transfected with Talin1 or control siRNA.The normal rat serum or HPS rat serum with a final concentration of 5%was added respectively.At 24 hours after cell transfection or at 24 hours(T1),48 hours(T2)and 72 hours(T3)of cell incubation,the protein expression of Talin1 and active Integin β1 in PASMCs were determined by Western blot;The migration of PASMCs was measured by Transwell chamber(T1)and scratch assay(T1 to T3).Results Compared to control group,with the extension of the stimula-tion time in the HPS group,the expression of Talin1 protein was upregulated,and the migration of PASMCs was gradually enhanced(P<0.05);Talin1 siRNA effectively silenced the Talin1 gene;The expression of ac-tive Integin β1 protein and the migration of PASMCs in the HPS group+si control were enhanced(P<0.05);Compared with the HPS group+si control,the expression of active Integin β1 protein and the migration of PASMCs in the HPS group+siTalin1 were significantly inhibited(P<0.05).Conclusions Downregulating ex-pression of Talin1 protein inhibits migration of PASMCs and expression of active Integin β1 protein induced by the serum from HPS rats.
7.Effect of different layers of masseter on the bony structure of facial lateral area
Yu-Qi ZHAO ; Jin-Rui JIANG ; Jin-Ran CHEN ; Ze-Chuan WANG ; Hou-En ZHOU ; Wen-Di XU ; Liu-Jun YONG
Acta Anatomica Sinica 2025;56(2):208-213
Objective To observe the morphology of the superficial,middle,and deep layers of the masseter muscle and related bony structures in the lateral facial region of adults through gross anatomy,and to probe into the effects of these muscle layers on the bony structures of the lateral facial region.Methods The bilateral masseter muscles of 12 adult cadavers were exposed,and the superficial,middle,and deep layers were separated and measured for muscle length,tendon length,and muscle belly length.After the masseter muscles were stripped,the total thickness was measured,and the mandible and zygomatic arch were exposed to measure the angle of the mandibular angle,thickness of the zygomatic arch,and width of the zygomatic arch.Observations were made of the masseter tuberosities,and statistical analysis was conducted on their interrelations.Results The zygomatic arch thickness was positively correlated with the length of superficial,middle and deep masseter muscles and the length of superficial and middle masseter belly(r superficial masseter length=0.624,r middle masseter length=0.787,r deep masseter length=0.423,r superficial masseter belly length=0.493,r middle masseter belly length=0.548).The width of the zygomatic arch was positively correlated with the lengths of the superficial and middle muscle layers and the middle muscle belly length(r superficial masseter length=0.527,r middle masseter length=0.521,r middle masseterbelly length=0.437).The angle of the mandibular angle was only negatively correlated with the middle muscle belly length(r=-0.422).The tuberosities of the superficial and middle masseter muscles were not affected by the corresponding muscle layers;However,the tuberosity of the deep masseter was negatively correlated with the length of the deep muscle and the length of the deep tendon(r deep masseter length=-0.543,r deep masseter tendon length=-0.443).Conclusion In the masseter muscle layers of Chinese individuals,the superficial and middle layers have the most significant impact on the bony structures structures of the lateral facial region.These findings are of guiding significance for the remodeling of structures in the lateral facial region.
8.Singapore clinical guideline on parenteral nutrition in adult patients in the acute hospital setting.
Johnathan Huey Ming LUM ; Hazel Ee Ling YEONG ; Pauleon Enjiu TAN ; Ennaliza SALAZAR ; Tingfeng LEE ; Yunn Cheng NG ; Janet Ngian Choo CHONG ; Pay Wen YONG ; Jeannie Peng Lan ONG ; Siao Ching GOOI ; Kristie Huirong FAN ; Weihao CHEN ; Mei Yoke LIM ; Kon Voi TAY ; Doris Hui Lan NG
Annals of the Academy of Medicine, Singapore 2025;54(6):350-369
INTRODUCTION:
The primary objective of this guideline is to establish evidence-based recommendations for the clinical use of parenteral nutrition (PN) in adult patients within the acute hospital setting in Singapore.
METHOD:
An expert workgroup, consisting of healthcare practitioners actively involved in clinical nutrition support across all public health institutions, systematically evaluated existing evidence and addressed clinical questions relating to PN therapy.
RESULTS:
This clinical practice guideline developed 30 recommendations for PN therapy, which cover these key aspects related to PN use: indications, patient assess-ment, titration and formulation of PN bags, access routes and devices, and monitoring and management of PN-related complications.
CONCLUSION
This guideline provides recommendations to ensure appropriate and safe clinical practice of PN therapy in adult patients within the acute hospital setting.
Humans
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Singapore
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Parenteral Nutrition/adverse effects*
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Adult
9.Risk prediction of Reduning Injection batches by near-infrared spectroscopy combined with multiple machine learning algorithms.
Wen-Yu JIA ; Feng TONG ; Heng-Xu LIU ; Shu-Qin JIN ; Yong-Chao ZHANG ; Chen-Feng ZHANG ; Zhen-Zhong WANG ; Xin ZHANG ; Wei XIAO
China Journal of Chinese Materia Medica 2025;50(2):430-438
In this paper, near-infrared spectroscopy(NIRS) was employed to analyze 129 batches of commercial products of Reduning Injection. The batch reporting rate was estimated according to the report of Reduning Injection in the direct adverse drug reaction(ADR) reporting system of the drug marketing authorization holder of the Center for Drug Reevaluation of the National Medical Products Administration(National Center for ADR Monitoring) from August 2021 to August 2022. According to the batch reporting rate, the samples of Reduning Injection were classified into those with potential risks and those being safe. No processing, random oversampling(ROS), random undersampling(RUS), and synthetic minority over-sampling technique(SMOTE) were then employed to balance the unbalanced data. After the samples were classified according to appropriate sampling methods, competitive adaptive reweighted sampling(CARS), successive projections algorithm(SPA), uninformative variables elimination(UVE), and genetic algorithm(GA) were respectively adopted to screen the features of spectral data. Then, support vector machine(SVM), logistic regression(LR), k-nearest neighbors(KNN), naive bayes(NB), random forest(RF), and artificial neural network(ANN) were adopted to establish the risk prediction models. The effects of the four feature extraction methods on the accuracy of the models were compared. The optimal method was selected, and bayesian optimization was performned to optimize the model parameters to improve the accuracy and robustness of model prediction. To explore the correlations between potential risks of clinical use and quality test data, TreeNet was employed to identify potential quality parameters affecting the clinical safety of Reduning Injection. The results showed that the models established with the SVM, LR, KNN, NB, RF, and ANN algorithms had the F1 scores of 0.85, 0.85, 0.86, 0.80, 0.88, and 0.85 and the accuracy of 88%, 88%, 88%, 85%, 91%, and 88%, respectively, and the prediction time was less than 5 s. The results indicated that the established models were accurate and efficient. Therefore, near infrared spectroscopy combined with machine learning algorithms can quickly predict the potential risks of clinical use of Reduning Injection in batches. Three key quality parameters that may affect clinical safety were identified by TreeNet, which provided a scientific basis for improving the safety standards of Reduning Injection.
Spectroscopy, Near-Infrared/methods*
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Drugs, Chinese Herbal/administration & dosage*
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Machine Learning
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Algorithms
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Humans
;
Quality Control
10.Metabolomics combined with network pharmacology reveals mechanism of Jiaotai Pills in treating depression.
Guo-Liang DAI ; Ze-Yu CHEN ; Yan-Jun WANG ; Xin-Fang BIAN ; Yu-Jie CHEN ; Bing-Ting SUN ; Xiao-Yong WANG ; Wen-Zheng JU
China Journal of Chinese Materia Medica 2025;50(5):1340-1350
This study aims to explore the mechanism of Jiaotai Pills in treating depression based on metabolomics and network pharmacology. The chemical constituents of Jiaotai Pills were identified by UHPLC-Orbitrap Exploris 480, and the targets of Jiaotai Pills and depression were retrieved from online databases. STRING and Cytoscape 3.7.2 were used to construct the protein-protein interaction network of core targets of Jiaotai Pills in treating depression and the "compound-target-pathway" network. DAVID was used for Gene Ontology(GO) function and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses of the core targets. The mouse model of depression was established with chronic unpredictable mild stress(CUMS) and treated with different doses of Jiaotai Pills. The behavioral changes and pathological changes in the hippocampus were observed. UHPLC-Orbitrap Exploris 120 was used for metabolic profiling of the serum, from which the differential metabolites and related metabolic pathways were screened. A "metabolite-reaction-enzyme-gene" network was constructed for the integrated analysis of metabolomics and network pharmacology. A total of 34 chemical components of Jiaotai Pills were identified, and 143 core targets of Jiaotai Pills in treating depression were predicted, which were mainly involved in the arginine and proline, sphingolipid, and neurotrophin metabolism signaling pathways. The results of animal experiments showed that Jiaotai Pills alleviated the depression behaviors and pathological changes in the hippocampus of the mouse model of CUMS-induced depression. In addition, Jiaotai Pills reversed the levels of 32 metabolites involved in various pathways such as arginine and proline metabolism, sphingolipid metabolism, and porphyrin metabolism in the serum of model mice. The integrated analysis showed that arginine and proline metabolism, cysteine and methionine metabolism, and porphyrin metabolism might be the key pathways in the treatment of depression with Jiaotai Pills. In conclusion, metabolomics combined with network pharmacology clarifies the antidepressant mechanism of Jiaotai Pills, which may provide a basis for the clinical application of Jiaotai Pills in treating depression.
Animals
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Drugs, Chinese Herbal/chemistry*
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Depression/genetics*
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Mice
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Network Pharmacology
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Metabolomics
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Male
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Disease Models, Animal
;
Humans
;
Protein Interaction Maps/drug effects*
;
Antidepressive Agents

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