1.Preliminary study on an improved method for constructing internal quality control framework of ELISA
Youbin DUAN ; Rui WANG ; Le CHANG ; Changwen QIU ; Zhiqiang LI ; Gengrui CHEN ; Jingjuan YANG ; Qing HE ; Lunan WANG
Chinese Journal of Blood Transfusion 2026;39(1):103-108
Objective: To propose an improved method for constructing the internal quality control (IQC) framework for ELISA assays and validate its efficacy by statistically analyzing IQC data from nine blood center laboratories. Methods: 1) IQC data was collected from nine blood centers and analyzed using a domestic HBsAg ELISA detection kit as an example. 2) Differences between IQC values across batches within Blood Center 1 were assessed. 3) Statistical analyses were performed on batch usage, number of batches used, days of use, number of QC points, batch-specific means, and coefficients of variation (CV) across all nine centers. 4) Using the improved construction method for IQC framework, provisional and permanent frames were established for batches within Blood Center 1 and Blood Center 9, followed by outlier determination. Results: 1) Statistically significant differences were observed in IQC data between batches within Blood Center 1 (P<0.01). It is recommended that both the control material/reagents and the control chart framework be replaced simultaneously. 2) There were substantial differences among 9 blood centers regarding the control material/reagent lot numbers used, the number of QC runs per batch, and the QC values for identical lots. Therefore, individual laboratories should establish their own IQC chart frameworks. 3) The improved IQC framework construction method for ELISA assays is as follows: provisional frames are established via frame-shifting, using the pre-experimental mean and cumulative coefficient of variation (CV) from the preceding batch. For batches used >20 days with >20 QC points, permanent frames are constructed by aggregating in-control data accumulated over ≥20 days with ≥20 points to calculate cumulative mean and standard deviation. The provisional and permanent frames constructed by this method identified all 26 extreme outliers across Blood Centers 1 and 9 as out-of-control. Among the 218 general outliers, 10 were classified as normal by the provisional frames, while the remainder were designated as warnings or out-of-control. This method effectively monitors assay stability. Conclusion: Based on the statistical analysis of IQC practices across blood centers of varying scales, combined with the inherent characteristics of ELISA assays and the batch-to-batch instability of reagents/QC materials, it is recommended to reconstruct QC charts upon lot changes. The proposed method—utilizing frame-shifting for provisional frames and establishing permanent frames based on cumulative data—is applicable to blood center laboratories of differing sizes and effectively monitors the stability of the ELISA assay process.
2.Mechanism of Xiao Qinglongtang Intervening Ferroptosis in Allergic Rhinitis Rats via Regulating SIRT1/SLC7A11 Signaling Pathway
Yuanyuan JI ; Hong ZHU ; Jingjuan AN ; Heng XIN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):113-119
ObjectiveTo observe the effect of Xiao Qinglongtang on ferroptosis in allergic rhinitis rats and explore its specific mechanism of action. MethodsSixty SD rats were randomly divided into a blank group, a model group, a loratadine group (0.9 mg·kg-1), and low-, medium-, and high-dose Xiao Qinglongtang groups (2.14, 4.28, and 8.56 g·kg-1), 10 rats per group. After 2 weeks of drug treatment, behavioral scores were observed in 6 groups of rats. Hematoxylin-eosin (HE) staining was used to observe changes in nasal mucosal tissue morphology, and Prussian blue staining was used to observe iron deposition. Enzyme-linked immunosorbent assay (ELISA) was used to detect reactive oxygen species (ROS), Fe2+ ions, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH) in each group. Immunofluorescence assay was used to detect ROS content and sirtuin 1 (SIRT1) expression in nasal mucosal tissue. Western blot was used to detect the expression of SIRT1, solute carrier family 7 member 11 (SLC7A11), p53 acyl-CoA synthetase long-chain family member 4 (ACSL4), and glutathione peroxidase 4 (GPX4) proteins in nasal mucosal tissue. ResultsCompared with the blank group, the model group exhibited obviously increased behavioral scores, severe nasal mucosal damage, obvious increase in iron deposition, significant decreases in GSH and SOD levels, obvious increases in MDA, Fe2+, and ROS fluorescence area proportions (P<0.05), decreased protein expression levels of GPX4, SLC7A11, and SIRT1, and obvious increases in p53 and ACSL4 expression (P<0.05). Compared with the model group, Xiao Qinglongtang groups of all doses showed reduced rat behavioral scores, obviously improved nasal mucosal damage, obviously reduced iron deposition (P<0.05), obviously increased GSH and SOD levels, obviously reduced MDA, Fe2+, ROS fluorescence area proportions (P<0.05), increased GPX4, SLC7A11, and SIRT1 protein expression levels, and obviously reduced p53 and ACSL4 (P<0.05). ConclusionXiao Qinglongtang may achieve the goal of treating allergic rhinitis by regulating the SIRT1/SLC7A11 signaling pathway and inhibiting lipid peroxidation and ferroptosis.
3.Airborne PM2.5 and Parkinson's disease: An updated meta-analysis
Yixian WANG ; Jianjun WU ; Rui HU ; Jingjuan JU
Journal of Environmental and Occupational Medicine 2024;41(2):168-174
Background An association between atmospheric fine particulate matter (PM2.5) exposure and Parkinson's disease (PD) has been suggested by previous studies, but the results of current epidemiological studies are still inconclusive. Objective To systematically evaluate the relationship between exposure to ambient PM2.5 and the risk of PD, as well as to explore potential influencing factors, aiming to provide scientific evidence for formulating early prevention strategies for PD. Methods Cochrane Library, PubMed, Web of Science, Medline, Embase, China National Know-ledge Infrastructure (CNKI), Wanfang Database, and VIP Chinese Science and Technology Journal Database were queried. The search terms included Parkinson's disease, particulate matter 2.5, and PM2.5 in both Chinese and English. Cohort studies examining the association between atmospheric PM2.5 exposure and the risk of PD were collected and searched from the inception of each database to June 26, 2023. The identified literature was screened, and the basic information of the included studies and their research subjects, outcome indicators, quantitative results of each study, as well as the information required by bias risk assessment were extracted. The Newcastle-Ottawa Scale was employed to assess the risk of literature bias. Meta-analysis, subgroup analysis, sensitivity analysis, and publication bias analysis were conducted in Stata 15.0 software. Results Twelve cohort studies were identified. A total of 17443136 participants with follow-up periods ranging from 3.5 to 22 years were included in the analysis. The meta-analysis, utilizing a random-effects model, revealed that PD risk was elevated by 6% after exposure to PM2.5 [HR=1.06 (95%CI: 1.02, 1.11), P=0.006]. The subgroup analysis demonstrated that exposure to PM2.5 increased PD risk by 6% in North America [HR=1.06 (95%CI: 1.00, 1.12), P=0.033] and by 17% in East Asia [HR=1.17 (95%CI: 1.02, 1.33), P=0.020]. However, the effect was not statistically significant in Europe. PD risk exhibited a 7% rise [HR=1.07 (95%CI: 1.02, 1.14), P=0.011] in individuals aged 60 years and older, which was different from that in individuals younger than 60 years. Exposure to various concentrations of PM2.5 was observed to associate with an elevated risk of PD. The inclusion of adjustments for PD-related comorbidities did not alter the conclusion that ambient PM2.5 exposure might elevate the risk of PD. The studies with a follow-up duration exceeding 5 years and reporting more than 1000 PD cases suggested a significant increase in the risk of PD due to ambient PM2.5 exposure [HR=1.06 (95%CI: 1.01, 1.12), P=0.012; HR=1.06 (95%CI: 1.01, 1.11), P=0.027, respectively]. Conversely, no significant association was identified between ambient PM2.5 exposure and the risk of PD within the cohorts with a follow-up duration of less than 5 years and reporting fewer than 1000 PD cases [HR=1.09 (95%CI: 0.95, 1.26), P=0.214; HR=1.12 (95%CI: 0.98, 1.02), P=0.092, respectively]. The sensitivity analysis showed that the results were stable. The publication bias analysis and the combined trim-and-fill method showed that the results were robust. Conclusion The risk of PD could be increased by ambient PM2.5 exposure and influenced by age and area. The research results might be affected by the duration of follow-up and the quantity of PD cases reported.
4.Comparison of different atomizing inhalation times on noninvasive ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease
Jingjuan XU ; Yan YANG ; Yan LIU ; Li YAO ; Wenxia WAN ; Nan LING
Chinese Journal of Practical Nursing 2024;40(1):20-26
Objective:To compare the dynamic changes of transcutaneous partial pressure of carbon dioxide (PtCO 2) and treatment effect of non-invasive intermittent nebulization and non-invasive simultaneous nebulization in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods:This was a randomized parallel controlled trial study. A total of 70 patients with acute exacerbation of COPD in Changzhou First People′s Hospital from October 2021 to September 2022 were selected by convenience sampling method, and divided into control group and experimental group by randomized digits table method with 35 cases in each group. The control group was given non-invasive intermittent oxygen-driven nebulization, and the experimental group was given non-invasive simultaneous oxygen-driven nebulization. The PtCO 2 values at 0, 5, 10, 15 min (the end point of atomization) of the 2 groups were observed, the daily arterial blood gas analysis indexes (mainly including PaCO 2, PaO 2 and pH) were recorded, and the clinical pulmonary infection score and the self-assessment score of COPD patients were recorded before treatment, on the 4th and 7th day of treatment. Results:Finally, 33 patients were included in both the control group and the experimental group. There were 25 males and 8 females in the control group, aged (75.33 ± 8.24) years old. There were 25 males and 8 females in the experimental group, aged (72.39 ± 8.56) years old. The PtCO 2 values at 0, 5, 10, 15 min in the control group were (63.83 ± 12.47), (64.40 ± 12.57), (65.42 ± 13.77), (66.62 ± 14.59) mmHg (1 mmHg=0.133 kPa). There were statistically significant differences in PtCO 2 at all time points ( F=8.05, P<0.01). Further pairwise comparison by Sidak method showed that there were statistically significant differences in PtCO 2 at 15 min compared with 0, 5, 10 min (all P<0.05). The PtCO 2 values at 0, 5, 10, 15 min in the experimental group were (67.62 ± 11.89), (67.15 ± 12.12), (67.82 ± 12.22), (68.15 ± 12.09) mmHg. There was no statistically significant difference in PtCO 2 at all time points ( F=2.00, P>0.05). The PaCO 2 and pH value of the two groups were improved with the treatment time, the control group had a statistically significant difference on the 4th day of treatment compared with before treatment ( P<0.05), while the experimental group on the second day of treatment compared with before treatment ( P<0.05). Conclusions:Both kinds of nebulization have achieved good therapeutic effects, but non-invasive simultaneous nebulization can better maintain the stability of PtCO 2 in the process of nebulization with higher safety, and can improve the arterial blood gas index PaCO 2 and pH value of patients earlier, which is a more suitable nebulization method for the combination of non-invasive ventilation and nebulization, especially for patients with hypercapnia.
5.Mechanism of Guangdong Shenqu in regulating intestinal flora in mice with food stagnation and internal heat based on 16S rDNA sequencing
Yani Jiang ; Zhenhong Zhang ; Han Chen ; Yanmin Wang ; Yanrui Xu ; Zijie Chen ; Yan Xu ; Jingjuan Wang
Journal of Traditional Chinese Medical Sciences 2024;11(2):232-244
Objective:
To investigate the effect of Guangdong Shenqu (GSQ) on intestinal flora structure in mice with food stagnation through 16S rDNA sequencing.
Methods:
Mice were randomly assigned to control, model, GSQ low-dose (GSQL), GSQ medium-dose (GSQM), GSQ high-dose (GSQH), and lacidophilin tablets (LAB) groups, with each group containing 10 mice. A food stagnation and internal heat mouse model was established through intragastric administration of a mixture of beeswax and olive oil (1:15). The control group was administered normal saline, and the model group was administered beeswax and olive oil to maintain a state. The GSQL (2 g/kg), GSQM (4 g/kg), GSQH (8 g/kg), and LAB groups (0.625 g/kg) were administered corresponding drugs for 5 d. After administration, 16S rDNA sequencing was performed to assess gut microbiota in mouse fecal samples.
Results:
The model group exhibited significant intestinal flora changes. Following GSQ administration, the abundance and diversity index of the intestinal flora increased significantly, the number of bacterial species was regulated, and α and β diversity were improved. GSQ administration increased the abundance of probiotics, including Clostridia, Lachnospirales, and Lactobacillus, whereas the abundance of conditional pathogenic bacteria, such as Allobaculum, Erysipelotrichaceae, and Bacteroides decreased. Functional prediction analysis indicated that the pathogenesis of food stagnation and GSQ intervention were primarily associated with carbohydrate, lipid, and amino acid metabolism, among other metabolic pathways.
Conclusion
The digestive mechanism of GSQ may be attributed to its role in restoring diversity and abundance within the intestinal flora, thereby improving the composition and structure of the intestinal flora in mice and subsequently influencing the regulation of metabolic pathways.
6.Correlation between brachial and ankle pulse wave velocity and cardiac structure and function in type 2 diabetes mellitus patients
Zhenya WU ; Hongmei MA ; Lijuan WANG ; Shengnan LIU ; Fanfan LI ; Jingjuan LI ; Ruifei YANG ; Yuanyuan LIU ; Jinyang WANG
Chinese Journal of Diabetes 2024;32(9):641-645
Objective To explore the correlation between brachial and ankle pulse wave conduction velocity(baPWV)and cardiac structure and function in patients with type 2 diabetes mellitus(T2DM).Methods A total of 443 patients with T2DM who were treated in The Endocrinology Department of Gansu Provincial People's Hospital were enrolled in this study from June 2022 to October 2023.All the patients were divided into simple T2DM group(T2DM,baPWV<1400 cm/s,n=221)and atherosclerosis group(AS,baPWV≥1400 cm/s,n=222)based on baPWV.The cardiac ultrasound diagnostic instrument was used to record left ventricular ejection fraction(LVEF),end diastolic left ventricular diameter(LVd),end diastolic interventricular septal thickness(IVSd),end diastolic left ventricular posterior wall thickness(LVPWd),ratio of early to late diastolic peak velocity of mitral valve annulus(E/A),and ratio of early diastolic peak velocity of mitral valve orifice to early diastolic peak velocity of mitral valve annulus(E/E').Results Age,DM duration,SBP,DBP,HbA1c,TG,ABI,LVEF,IVSd,LVPWd,E/A<1,E/E'>14,were higher in AS group than in T2DM group(P<0.05 or P<0.01).Spearman correlation analysis shows that E/A<1 was positively correlated with age,DM duration,BMI,SBP,DBP,and ABI(P<0.05 or P<0.01),while negatively correlated with baPWV(P<0.01).Pearson correlation analysis shows that LVPWd was positively correlated with age,DM duration,BMI,SBP,DBP,baPWV,and Scr(P<0.05 or P<0.01).Logistic regression analysis shows that baPWV,ABI,and SBP were the influencing factors for left ventricular diastolic dysfunction.The analysis of the working characteristic curve of the subjects shows that the area under the curve of baPWV,SBP and ABI for predicting left ventricular diastolic dysfunction is 0.647,0.643,and 0.624,with the best cutoff points being 1398.5 cm/s,125.5 mmHg,and 1.107.Conclusions baPWV is closely related to cardiac structure and function in T2DM patients.As baPWV increases,the risk of left ventricular diastolic insufficiency and hypertrophy rises.
7.Research progresses of PET molecular imaging for Parkinson disease complicated with levodopa-induced dyskinesia
Shuang LI ; Tianbin SONG ; Chang YANG ; Jingjuan WANG ; Chun ZHANG ; Jie LU
Chinese Journal of Medical Imaging Technology 2024;40(5):774-778
Levodopa is the standard therapy for Parkinson disease(PD),however,with the progression of the disease and long-term treatment,levodopa-induced dyskinesia(LID)can occur,greatly reducing the quality of patients'life.PET brain molecular imaging can detect the uptake and distribution of imaging agents at the molecular level in vivo,thereby reflecting the brain function and metabolism of patients with PD complicated with LID,which is helpful for early clinical diagnosis and treatment.The research progresses of PET molecular imaging for PD complicated with LID were reviewed in this article.
8.Impact of different reconstruction algorithms on PET image quality and diagnostic efficiency in patients with temporal lobe epilepsy
Kun SHANG ; Jie HU ; Zhenming WANG ; Jingjuan WANG ; Bixiao CUI ; Xiaoyin XU ; Jie LU
Chinese Journal of Nuclear Medicine and Molecular Imaging 2024;44(11):678-683
Objective:To evaluate the value of time-of-flight (TOF) combined with point spread function (PSF) reconstruction for the improvement of brain PET images and lesion localization in patients with temporal lobe epilepsy (TLE).Methods:A retrospective collection of brain 18F-FDG PET imaging data of 52 hospitalized patients with TLE (30 males, 22 females, age: (26.7±7.1) years) and 26 healthy volunteers (14 males, 12 females, age: ( 31.7±6.8) years) from Xuanwu Hospital between 2017 and 2019 was conducted. Images were reconstructed and divided into 4 groups based on different algorithms: ordered subset expectation maximization (OSEM), OSEM+ TOF, OSEM+ PSF, and OSEM+ TOF+ PSF. The image quality, clarity, noise, and the clarity of lesion display of all subjects were visually analyzed using a four-point scale. The signal-to-noise ratio (SNR), contrast, and asymmetry index (AI) of the lesions were calculated. Differences in visual scores, SNR, contrast, and AI among the 4 groups were analyzed using one-way analysis of variance. The ROC curve was used to analyze the efficiency of PET images in localization of epileptogenic foci. Results:The visual score of OSEM+ TOF+ PSF group was the highest (4.0±0.0) among healthy volunteers; compared with OSEM group, OSEM+ TOF+ PSF group showed lower SNR (decreased by 46.6%; the lower the SNR value, the better the image quality) and contrast (increased by 29.8%). Visual assessment of PET images of patients with TLE showed that the scores of OSEM+ TOF+ PSF group , OSEM+ PSF group , OSEM+ TOF group and OSEM group were decreased in order (4.0±0.0 vs 3.4±0.5 vs 2.3±0.4 vs 1.0±0.0; F=884.0, P<0.001); SNRs of those 4 groups were increased in order ((5.2±2.4)% vs (6.2±2.4)% vs (7.9±2.6)% vs (8.9±3.5)%; F=18.82, P<0.001). The contrast and AI of the lesions in 4 groups were as follows: OSEM+ TOF+ PSF (contrast: 0.81±0.03; AI: 0.28±0.05) > OSEM+ TOF (0.74±0.05; 0.23±0.06) > OSEM+ PSF (0.72±0.06; 0.22±0.07) > OSEM (0.64±0.05; 0.19±0.06) ( F values: 107.10, 19.94, both P<0.001). MRI found unilateral hippocampal sclerosis in 32 patients, and the rest 20 patients with TLE were MRI-negative. ROC curve analysis showed that visual analysis and SUV ratio (SUVR) of lesion/contralateral ROI based on OSEM+ TOF+ PSF PET image could localize epileptogenic foci efficiently, with AUC of 0.874 in MRI-positive patients, and AUC of 0.932 in MRI-negative patients. Conclusions:The application of TOF and PSF significantly improves the quality of PET images. The combined use of both techniques yields the best results and aids in the localization of epileptogenic foci in patients with TLE.
9.Pathogenesis of flunarizine-induced parkinsonism from gut-brain axis perspective
Nan DING ; Lixin PAN ; Changlin LIAN ; Zhifeng XU ; Yukai WANG ; Fen ZHANG ; Guanghua ZHAO ; Xiaojue LIANG ; Wenjie LAI ; Weiqi ZENG ; Jingjuan CHEN ; Guohua ZHANG
Chinese Journal of Neuromedicine 2024;23(4):333-339
Objective:To explore the pathogenesis of flunarizine-induced parkinsonism from gut-brain axis perspective.Methods:Thirty male C57BL/6 mice were randomly divided into control group and flunarizine group ( n=15). Mice in the control group were given 0.1 mL 50% polyethylene glycol 400+50% saline by gavage once/d for 2 weeks, while mice in the flunarizine group were given 6 mg/mL flunarizine+50% polyethylene glycol 400+50% saline by gavage at a daily dose of 30 mg/kg for 2 weeks. Body mass was recorded 1, 3, 5, 7, 10 and 14 d after drug administration, and motor function was assessed by rotarod test 14 d after drug administration; 16s RNA sequencing was performed in the feces to observe the intestinal flora; intestinal transit function was detected by Evans blue by gavage; and then, the mice were sacrificed and homogenate or frozen sections (brain and intestinal tissues) were prepared; dopamine-ergic neuron expression was detected by Western blotting; RT-qPCR was applied to detect the expressions of inflammatory factors in the substantia nigra, and immunofluorescent staining was used to detect the expressions of ZO-1 and Claudin-5 in the intestinal epithelial tissues. Results:Compared with the control group, the flunarizine group had lower body mass ratio 1, 3, 5, 7, 10 and 14 d after drug administration (ratio to body mass before drug administration). Compared with the control group, the flunarizine group had significantly shortened residence time in rod rotating and lower rotational speed when falling ( P<0.05). Compared with the control group, the flunarizine group had decreased tyrosine hydroxylase protein in the substantia nigra without significant difference ( P>0.05). Compared with the control group, the flunarizine group had significantly increased interleukin-6 and tumor necrosis factor-α in the substantia nigra (1.00±0.00 vs. 2.79±0.83; 1.00±0.00 vs. 3.39±1.37), significantly lower intestinal Evans blue propulsion rate (80.67%±4.51% vs. 50.67%±6.03%), and statistically decreased ZO-1 and Claudin-5 expressions in the colonic epithelial tissues (27.01±1.41 vs. 16.32±2.83; 37.00±2.80 vs. 24.52±2.12, P<0.05). Totally, 576 microorganisms were noted in both control group and flunarizine group, 744 in the control group alone, and 634 in the flunarizine group alone. The intestinal flora β diversity indices in the 2 groups were significantly different based on weighted Unifrac-principle coordinates analysis (PCoA, PCoA1: 39.88%; PCoA2: 30.69%). Compared with the control group, the microbial colony structure of mice in flunarizine group was dominated by phylum thick-walled bacteria and phylum warty microbacteria, and by families Muribaculaceae, Lachnospiraceae and Akkermansiaceae. Compared with the control group, the flunarizine group had significantly decreased relative abundance of Ackermannia spp. and Lactobacillus spp. in the intestinal flora ( P<0.05). Conclusion:Flunarizine may contribute to the pathogenesis of DIP by causing structural disturbances in the intestinal flora and inducing neuroinflammation based on the gut-brain axis.
10.Barriers to the Acceptance of Tuberculosis Preventive Treatment: A Multicenter Cross-sectional Study in China.
Jingjuan REN ; Fei HUANG ; Haifeng CHEN ; Huimin ZHANG ; Jianwei SUN ; Ahui ZHAO ; Zuhui XU ; Liqin LIU ; Huizhong WU ; Lanjun FANG ; Chengguo WU ; Qingya WANG ; Wenqian ZHANG ; Xinhua SUN ; Xiaoping LIU ; Jizheng YUAN ; Bohan CHEN ; Ni WANG ; Yanlin ZHAO
Biomedical and Environmental Sciences 2024;37(11):1303-1309
OBJECTIVE:
We aimed to understand the willingness and barriers to the acceptance of tuberculosis (TB) preventive treatment (TPT) among people with latent TB infection (LTBI) in China.
METHODS:
A multicenter cross-sectional study was conducted from May 18, 2023 to December 31, 2023 across 10 counties in China. According to a national technical guide, we included healthcare workers, students, teachers, and others occupations aged 15-65 years as our research participants.
RESULTS:
Overall, 17.0% (183/1,077) of participants accepted TPT. There were statistically significant differences in the acceptance rate of TPT among different sexes, ages, educational levels, and occupations ( P < 0.05). The main barriers to TPT acceptance were misconceptions that it had uncertain effects on prevention (57.8%, 517/894), and concerns about side effects (32.7%, 292/894).
CONCLUSION
An enhanced and comprehensive understanding of LTBI and TPT among people with LTBI is vital to further expand TPT in China. Moreover, targeted policies need to be developed to address barriers faced by different groups of people.
Humans
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China/epidemiology*
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Adult
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Male
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Female
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Cross-Sectional Studies
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Middle Aged
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Young Adult
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Adolescent
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Aged
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Latent Tuberculosis/prevention & control*
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Patient Acceptance of Health Care
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Tuberculosis/prevention & control*
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Antitubercular Agents/therapeutic use*
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Health Knowledge, Attitudes, Practice


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