BACKGROUND:Gradient artificial bone repair scaffolds can mimic unique anatomical features in musculoskeletal tissues,showing great potential for repairing injured musculoskeletal tissues. OBJECTIVE:To review the latest research advances in gradient artificial bone repair scaffolds for tissue engineering in the musculoskeletal system and describe their advantages and fabrication strategies. METHODS:The first author of the article searched the Web of Science and PubMed databases for articles published from 2000 to 2023 with search terms"gradient,bone regeneration,scaffold".Finally,76 papers were analyzed and summarized after the screening. RESULTS AND CONCLUSION:(1)As an important means of efficient and high-quality repair of skeletal system tissues,gradient artificial bone repair scaffolds are currently designed bionically for the natural gradient characteristics of bone tissue,bone-cartilage,and tendon-bone tissue.These scaffolds can mimic the extracellular matrix of native tissues to a certain extent in terms of structure and composition,thus promoting cell adhesion,migration,proliferation,differentiation,and regenerative recovery of damaged tissues to their native state.(2)Advanced manufacturing technology provides more possibilities for gradient artificial bone repair scaffold preparation:Gradient electrospun fiber scaffolds constructed by spatially differentiated fiber arrangement and loading of biologically active substances have been developed;gradient 3D printed scaffolds fabricated by layered stacking,graded porosity,and bio-3D printing technology;gradient hydrogel scaffolds fabricated by in-situ layered injections,simple layer-by-layer stacking,and freeze-drying method;and in addition,there are also scaffolds made by other modalities or multi-method coupling.These scaffolds have demonstrated good biocompatibility in vitro experiments,were able to accelerate tissue regeneration in small animal tests,and were observed to have significantly improved histological structure.(3)The currently developed gradient artificial bone repair scaffolds have problems such as mismatch of gradient scales,unclear material-tissue interactions,and side effects caused by degradation products,which need to be further optimized by combining the strengths of related disciplines and clinical needs in the future.

Objective:Based on the specific cleavage and non-specific "trans-cleavage" activities of the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein(CRISPR/Cas13), we established a visually amplification-free rapid detection technique of 2019-nCoV nucleic acid. This technique is easily processed with a low detection limit and good specificity.Methods:According to the 2019-nCoV gene sequence, specific CRISPR RNAs were screened and designed by bioinformatics analysis, and then synthesized as universal signal-strained RNA transcription targets in vitro to establish and optimize the reaction system. Moreover, the 2019-nCoV pseudoviral nucleic acid was used as a standard substance to evaluate the detection limit. A total of 65 positive samples were collected from various 2019-nCoV variants, while 48 negative samples included other clinically common respiratory pathogens, such as influenza A virus, influenza B virus, human parainfluenza virus, Klebsiella pneumonia, etc. All samples were tested by quantitative PCR (qPCR), digital PCR, and the method established in this study. The sensitivity and specificity of the newly established method were analyzed and evaluated. Results:With the newly established technique, the detection time for 2019-nCoV nucleic acid could be minimized to 6 minutes. In addition, the detection limit was 14 copies/μl when assisted by the displaying instrument, whereas it increased to 28 copies/μl with the naked eye. This technique had a sensitivity and specificity of 98.5% (66/67) and 100% (46/46) respectively, showing no statistically significant difference compared to the gold standard qPCR( P=1). Conclusions:This study has successfully established a CRISPR/Cas13a-based visually rapid detection technique for 2019-nCoV nucleic acid. This technique offers the advantages of a simple process, convenient operation, low environmental operating requirements, a detection limit close to qPCR, and a strong potential for on-site testing applications.

BACKGROUND:In clinical practice,the anterior superior iliac spine and posterior superior iliac spine are usually located by palpation,and the tilt of the pelvis is determined by visual observation method or photogrammetry.Among them,the visual observation method can only have qualitative conclusions,and its reliability is poor.The photogrammetry is not only more convenient and fast,but also can give more accurate quantitative data,which is one of the best clinical evaluation methods.However,there are no studies on the reliability of pelvic posture assessment using photogrammetry in China. OBJECTIVE:To evaluate the pelvic posture by visual observation method and photogrammetry,and to compare the reliability level of the two methods to guide clinical application. METHODS:Forty-five healthy subjects were selected and red marks were made at the bilateral anterior superior iliac spine and posterior superior iliac spine.Pelvic posture was photographed from the front,back(coronal plane),left,and right(sagittal plane).The left and right pelvic tilt angles(α,β angles)were selected from the front and back views,which represented the angle between the bilateral anterior superior iliac spine line or the bilateral posterior superior iliac spine line and the horizontal line.The anterior and posterior pelvic tilt angles(γ,θ angles)were selected from the side view,which represented the angle between the ipsilateral anterior superior iliac spine and posterior superior iliac spine line and the horizontal plane,indicating the sagittal plane pelvic tilt.Evaluation methods included visual observation method and photogrammetry.Two evaluators independently evaluated the pelvic α,β,γ,θ angles using the visual observation method first,and then recorded the pelvic α,β,γ,θ angles using the photogrammetry.After a one-month interval,the visual observation method and photogrammetry were performed again,and the pelvic α,β,γ,θ angles were recorded.The intraclass correlation coefficients were used to analyze the data obtained from the two evaluation methods and the before-and-after measurements:0.90-0.99 as an excellent correlation,0.80-0.89 as a good correlation,0.70-0.79 as a moderate correlation,and≤0.69 as a poor correlation.The standard error of measurement and the minimal detectable change with 95%confidence intervals were calculated to evaluate the inter-rater and intra-rater reliability. RESULTS AND CONCLUSION:(1)The interrater intraclass correlation coefficients of the visual observation method and photogrammetry were as follows:anterior view:0.682 and 0.718,posterior view:0.513 and 0.867,left view:0.739 and 0.960,and right view:0.756 and 0.971.The visual observation method showed poor correlation between the anterior and posterior views and moderate correlation between the left and right views,while the photogrammetry showed moderate correlation for the anterior view,good correlation for the posterior view,and excellent correlation for the left and right views.The standard error values of measurement were as follows:anterior view:3.266 and 1.625,posterior view:4.278 and 1.763,left view:5.935 and 1.787,and right view:5.723 and 1.698.The minimal detectable change values with 95%confidence intervals were as follows:anterior view:9.053 and 4.504,posterior view:11.858 and 4.887,left view:16.451 and 4.953,and right view:15.863 and 4.707.(2)The interrater intraclass correlation coefficients of the visual observation method and photogrammetry were as follows:anterior view:0.452 and 0.723,posterior view:0.483 and 0.904,left view:0.518 and 0.955,and right view:0.657 and 0.968.The visual observation method showed poor correlation in all four directions,while the photogrammetry showed moderate correlation for the anterior view and excellent correlation for the other three directions.The standard error values of measurement were as follows:anterior view:5.651 and 1.610,posterior view:4.237 and 1.523,left view:7.322 and 1.891,and right view:6.509 and 1.781.The minimal detectable change values with 95%confidence intervals were as follows:anterior view:15.664 and 4.463,posterior view:11.744 and 4.222,left view:20.296 and 5.242,and right view:18.042 and 4.937.(3)These results confirm that the sagittal and coronal plane photogrammetries have good intrarater and interrater reliability for evaluating pelvic posture,especially with the use of the photogrammetry,which has good data stability.This method is simple,fast,efficient,accurate,low-cost,and does not cause X-ray damage,and can qualitatively and quantitatively reflect the actual situation of the patient's pelvis,making it suitable for clinical use.

ObjectiveTo investigate the possible mechanism of Buzhong Yulin Decoction （补中愈淋汤） in the prevention and treatment of recurrent urinary tract infection. MethodsThe mouse models of recurrent urinary tract infection were established by uropathogenic Escherichia coli （UPEC） strain UTI89 by bladder perfusion， and the successful mouse models were randomly divided into a model group， an antibiotic group， and a low- and high-dose Buzhong Yulin Decoction group， with six mice in each group. In addition， 5 C57BL/6 mice without modelling were taken as blank group. The low- and high-dose Buzhong Yulin Decoction groups received 0.1 ml/10 g of decoction by gavage， with concentrations of 1.3 g/ml and 5.2 g/ml， respectively； the antibiotic group received 0.1 ml/10 g of levofloxacin hydrochloride solution with 5 mg/ml by gavage； the blank and model groups received 0.1 ml/10 g of distilled water by gavage. Each group was gavaged once a day for 7 consecutive days. The total number of urine marks， the number of central urine marks， and the total urine volume of the urine marks were observed by the urine marking test； HE staining was used to observe the histopathological changes in the bladder of mice； serum levels of the inflammatory factors interleukin 1β （IL-1β）， interleukin 6 （IL-6） and tumour necrosis factor α （TNF-α） were detected by ELISA； the morphology of the epithelial cells of bladder was observed by scanning electron microscopy； immunofluorescence assay to detect bladder tissue anti-UroPlakin 3A protein level and UPEC bacterial load； the spread plate method to detect urinary bacterial load and bacterial load of bladder epithelial cells； RT-PCR method to detect Ras-related protein Rab-11A （RAB11A） and Ras-related protein Rab-27B （RAB27B） mRNA level in bladder tissue； immunoblotting to detect microtubule-associated protein 1 light chain3 （LC3） and P62 protein levels in bladder tissue. ResultsCompared with the blank group， the bladder epithelial cell layers were lost and showed abnormal morphology in mice of the model group； bladder tissue UroPlakin 3A protein and RAB11A and RAB27B mRNA levels reduced， the total number of urine marks， the number of central urine marks， bladder tissue UPEC bacterial load， urinary bacterial load， bacterial load in bladder epithelial cells， serum IL-1β， IL-6， and TNF-α levels， and LC3 and P62 protein levels in bladder tissue all elevated （P＜0.05 or P＜0.01）. Compared with the model group， the bladder epithelial cell layers were intact and the morphology of epithelial cells were regular in the low- and high-dose Buzhong Yulin Decoction groups； the average surface area of bladder epithelial cells reduced， the levels of UroPlakin 3A protein and RAB11A and RAB27B mRNA in bladder tissues elevated， and total number of urine marks， the number of central urine marks， bladder tissue UPEC bacterial load， urinary bacterial load， bacterial load in bladder epithelial cells， serum IL-1β， IL-6， and TNF-α levels， and P62 protein levels in bladder tissue all reduced （P＜0.05 or P＜0.01）， but LC3 protein levels showed no statistically significant （P＞0.05）. In the antibiotic group， the bladder epithelial cells were partially missing and the morphology of epithelial cells was abnormal. Compared with the antibiotic group， the average surface area of the bladder epithelial cells in the mice increased in the low- and high-dose Buzhong Yulin Decoction groups， the bacterial load of the bladder epithelial cells decreased， and the P62 protein level of the bladder tissue decreased （P＜0.05）. When comparing between the low- and high-dose Buzhong Yulin Decoction groups， the differences in each index were not statistically significant （P＞0.05）. ConclusionBuzhong Yulin Decoction may prevent and treat recurrent urinary tract infection by repairing the bladder mucosal barrier， increasing RAB11A and RAB27B level and enhancing autophagy in bladder tissues， thereby facilitating bacterial clearance from bladder epithelial cells and reducing the bacterial load of bladder epithelial cells.

Objective:To analyze the efficacy and cost-effectiveness of probiotics in initial Helicobacter pylori ( H. pylori) eradication therapy. Methods:A total of 267 patients with positive H. pylori infection were randomly assigned to two groups, the control group ( n=133) received a 14-day bismuth agent quadruple therapy and the study group ( n=144) received conventional quadruple therapy plus probiotics from January 2020 to August 2021. Eradication status was assessed 4-12 weeks after treatment. The H.pylori eradication rate, adverse reactions, and cost-effectiveness were compared between the two groups. Results:The H.pylori eradication rate was higher in study group than that in the control group in intention-to-treat (ITT) (80.6%(108/134), 95% CI:73.8%-87.4% vs. 68.4%(91/133), 95% CI:60.4%-76.4%, P=0.022) and per-protocol (83.1%(108/130), 95% CI:76.5%-89.6% vs. 72.2%(91/126), 95% CI:64.3%-80.2%, P=0.037). The incidence of adverse effects in the study group was lower than that in the control group (8.2%(11/134) vs. 18.8%(25/133), χ 2=6.415, P=0.011). Cost-effectiveness analysis showed that compared with the control group, the incremental cost-effectiveness ratio (ICER) of the study group was 1 010.49 yuan. The single factor sensitivity analysis showed that the H.pylori eradication rate of the study group had a greater impact on the results, followed by that of the control group and the cost of bifidobacterium quadruplex viable tablets. The probability sensitivity analysis showed that when the willingness to pay value (WTP) was 2 500 yuan, the probability that the probiotics combined with the bismuth agent quadruple therapy group was more cost-effective than the simple bismuth agent quadruple therapy group was 91.2%. Conclusion:As initial Helicobacter pylori treatment, probiotics combined with the bismuth agent quadruple scheme has a higher eradication rate and a lower incidence of adverse events than the bismuth agent quadruple scheme.

Objective:To analyze the current status of duplicated reporting of brucellosis in China during 2005-2017, to understand the impact of duplicated reporting on the incidence of brucellosis, analyze the possible causes of duplicated reporting, and put forward propose solutions to further improve the brucellosis surveillance data quality.Methods:Data were from brucellosis case reporting cards in National Notifiable Disease Report System (NNDRS), Excel 2010 software was used to establish the database, the duplicated reporting was identified by using Spark DataFrame aggregation analysis in Python 3.2.Results:During 2005-2017, a total of 499 577 cases of brucellosis were reported, but the duplicated reporting rate was 75.76/10 000 (3 785/499 577). The duplicated reporting rate in same year was 37.21/10 000 (1 859/499 577), the duplicated reporting rate in other year was 39.87/10 000 (1 992/499 577) and the overall duplicated reporting rate increased year by year. The duplicated reporting rate in same institution was 33.59 % (1 271/3 785) and the duplicated reporting rate by other institutions was 66.41 % (2 514/3 785). Hospitals had the highest number of duplicated reporting (2 757), and community healthcare centers had the highest of duplicated reporting rate (281.27/10 000) (123/4 373). The reported incidence of brucellosis was 2.926 4/100 000 in 2017, the corrected incidence was 2.844 8/100 000 after removing the duplicated reporting, which was the maximum decrease from 2005 to 2017, the corrected incidence decreased by 2.79 %. From 2005 to 2017, the average reported incidence of brucellosis in Xinjiang Uygur autonomous region was 14.712 0/100 000, and the corrected incidence was 14.060 0/100 000 after removing the duplicate reporting, with a decrease by 4.43 %, the biggest decline in China. The average reported incidence of brucellosis in Ningxia Hui autonomous region was 13.987 1/100 000, and the corrected incidence of brucellosis was 13.662 2/100 000, with a decrease of 2.32 %, ranking second in China. The reasons for duplicated reporting of brucellosis included repeated medical care seeking in same or different medical institutions in same year or other year, including the repeated medical care seeking in other areas. Conclusions:During 2005-2017, the number of duplicated reporting of brucellosis cases was on the rise in China. Hospital and community health service centers had highest case number and rate of duplicate reporting respectively, the duplicated reporting was mainly caused by re-reporting by other institutions or in other years. The duplicated reporting of brucellosis had greatly affected the accuracy of surveillance data of brucellosis in some provinces, such as Xinjiang and Ningxia. It is recommended to further strengthen brucellosis reporting management, improve data quality of NNDRS.

Objective To investigate the effectiveness and safety of drug-eluting stent implantation following rotational atherectomy (RA)for severe coronary arteries calcification in elderly patients. Methods A total of 21 patients receiving RA and drug-eluting stent implantation were enrolled in this study in our cardiology department from Sep.2014 to Sep.2017. Twenty-one patients with 27 severe calcified lesions were treated with the stent implantation following RA . The primary endpoints of the study were the immediate operation success rate and the rate of major adverse cardiac and cerebral events (MACCE)at 6 month after surgery ,including angina recurrence ,need for target vessel revascularization ,myocardial infarction ,stent thrombosis and cardiovascular death. Results 14 patients(66.7% ,14/21)received RA by using 1.5 mm burr ,and 7 patients(33.3% ,7/21)by using both 1.25 mm and 1.5 mm burrs. The average ratio of burr to artery diameter was (0.5 ± 0.1). A total of 29 stents were successfully implanted in all patients (100% ,21/21 patients).None of the patients experienced any acute coronary artery rupture or other severe complications during percutaneous coronary intervention (PCI ) after RA. Two cases (2/21 ,9.5% ) suffered from slow flow ,and the coronary blood flow was restored to TIMI grade Ⅲ after treatment. The coronary blood flow in the other 19 cases(19/21 ,90.4% )was TIMI grade Ⅲ after RA.Intravascular ultrasonography (IVUS) showed that the stents were well adhered without stent rupture and intimal tear in 12 cases(12/21 , 57.1% ) ,and postdilation was performed in 9 cases(9/21 ,42.9% ).All patients were followed up for at least 6 months ,and target vessel revascularization and death were not found. Conclusions A drug-eluting stent implantation following rotational atherectomy is effective and safe for treating severe coronary arteries calcification in elderly coronary heart disease patients. The IVUS-guided rotational atherectomy combined with drug-eluting stent implantation can reduce the risk of MACCE ,such as under-expansion stent ,stent thrombosis ,myocardial infarction ,cardiovascular death ,and improve clinical outcomes in elderly patients with severe coronary arteries calcification.

Objective To compare different regimens of intraperitoneal injection of cyclophosphamide (CTX) to establish a rabbit model of premature ovarian failure (POF), and provide a useful experimental tool for further research of premature ovarian failure. Methods A total of twenty-one 5-6 months old rabbits were randomly divided into 4 groups. The group A (normal control group) included 3 rabbits without any treatment. The group B (the first model group) included 6 rabbits, received a single intraperitoneal injection of 50 mg/kg cyclophosphamide. Six rabbits in the group C (the second model group) were injected with 50 mg/kg cyclophosphamide once daily for 2 days. The group D (the third model group, also n=6) was injected with 50 mg/kg cyclophosphamide on the first day and then followed by 8 mg/ (kg·d) injection q.d. in the 14 consecutive days. Body weight and ovary weight of the rabbits in each group were measured, and the changes of body weight and the ovary index were analyzed. Morphological changes of the ovarian follicles were observed by HE staining and the numbers of normal and abnormal follicles at different developmental stages were counted and analyzed. Cell apoptosis was analyzed by TUNEL staining and changes in the serum levels of estradiol (E2) were detected by ELISA. Results The body weight of rabbits in both groups B and group C was not significantly changed during the experimental period (P＞ 0. 05). Rabbits in the group D showed a slight growth (P ＜ 0. 05) and high mortality. The ovary index in group C was significantly lower than that in the group A (P ＜ 0. 05). The ratios of abnormal primordial and primary follicles in groups B and C were significantly increased (P ＜ 0. 017), and the ratio of abnormal primordial follicles in the group C was increased more significantly (P ＜ 0. 017). However, there was no significant difference in the ratios of abnormal primary follicles between groups B and C (P＞ 0. 017). Among the groups A, B and C, there was no significant difference in the ratios of abnormal secondary and antral follicles (P＞ 0. 05). Apoptosis mainly occurred in granulosa cells of the ovarian follicles. The apoptosis rate of groups B and C was significantly higher than that in the group A (P ＜ 0. 05), and the apoptosis rate of group C was higher than that in the group B (P ＜ 0. 05). In the group B, the serum E2 level reached the peak value on the 7th day, significantly higher than that on the 35th day (P ＜ 0. 05), and then the level was decreased gradually. In the group C, the E2 level was continuously decreased and the level on the last day before drug injection was significantly higher than that at the 35th day (P ＜ 0. 05). Conclusions Intraperitoneal injection of 50 mg/kg cyclophosphamide once daily for 2 days is a most suitable method for the establishment of rabbit model of premature ovarian failure (POF).

Objective To evaluate the clinical improvements after autologous bone marrow mononuclear cells (BMMNCs) percutaneously injected into coronary artery in patients with heart failure due to non-ischemic cardiomyopathy using PET myocardial peffusion/metabolic imaging.Methods From February 2011 to October 2012,40 patients with heart failure due to non-ischemic cardiomyopathy were selected.The test group including 15 patients (13 males,2 females,average age (57.5±14.5) years) received the autologous BMMNCs intracoronary injection on the basis of drug treatment.The other 25 cases (21 males,4 females,average age (58.0±12.0) years) were taken as the control group and only received the drug treatment.All patients were followed up for 24 months,and the myocardial perfusion/metabolism imaging,echocardiography,brain natriuretic peptide (BNP) test,6-minute walking experiment were performed.The data were analyzed by two-sample t test.Results During the follow-up period,the test group had no ventricular arrhythmia and other serious complications,and the patients' symptoms had been improved.There was no change in myocardial perfusion after treatment of autologous BMMNCs,but the myocardial metabolic defect by volume reduced from (43.79± 17.99) cm3 to (28.19±9.27) cm3 (t =3.33,P＜0.01) 24 months after the treatment.The myocardial metabolic defect by volume at the baseline and after 24 months in the control group was (43.30±15.70) cm3,(48.51±15.77) cm3 respectively (t=1.01,P＞0.05).In the test group,the left ventricular end-diastolic diameter decreased from (64.0±8.0) mm to (59.0±7.0) mm 24 months after the treatment (t=2.04,P＜0.05),and the left ventricular ejection fraction was significantly higher than that before treatment:(45.0±4.0) ％ vs (27.0±6.0) ％ (t =10.81,P＜0.01).Conclusion PET myocardial perfusion/metabolic imaging can be used as tools in evaluating the therapeutic effect of autologous BMMNCs in patients with heart failure due to non-ischemic cardiomyopathy.

Objective To study the plasma heat shock protein 90 alpha (HSP90 α) in the diagnosis of lung cancer.Methods Chose 166 cases of patients with lung cancer,lung cancer group,the same physical examination of 20 cases of normal (control group),application of plasma concentration of HSP90 α enzyme-linked immunoassay detection,chemiluminescence detection of CEA,NSE,SCC and CYFRA21-1,of the two groups of data by t test statistical analysis,compared two groups of plasma HSP90 α level.With plasma HSP90 alpha was greater than 86 ng/ml for the critical value,calculation of HSP90 α testing sensitivity.Patients with lung cancer by histopathologic classification,compare different tumor classification in patients with plasma HSP90 α level.Used Pearman's correlation method to analyse the relationship of HSP90 α,CEA and NSE in patients with lung cancer,between SCC and CYFRA21-1 and used ROC curve to evaluate HSP90 α efficiency to the diagnosis of lung cancer.Results ① In lung cancer group and control group in the indicators HSP90 α,CEA,NSE,SCC and respectively CYFRA21-1 190.33±105.86 vs 41.02±19.73 ng/ml,8.68±5.02 vs 4.02±1.36 ng/ml,36.32±13.16 vs 8.32 ±3.96 ng/ml,6.21±1.62 vs 1.23±0.64 ng/ml,10.63±4.33 vs 3.02±1.66 ng/ml.Compared with control group (t=10.48,8.66,12.36,9.52,15.36,P＜0.01),the difference was statistically significant.② For biological reference range (HSP90 α:0～86 ng/ml,CEA 1.0～5 ng/ml,NSE:1.0～17.5 ng/ml,SCC:0.2～1.6 ng/ml,CYFRA21-1:1.0～2.6 ng/ ml) as the standard in lung cancer group,HSP90 α increased 73.49 ％,CEA increased 19.27 ％,NSE increased 19.27 ％,CYFRA21-1 (21.68％) and SCC increased 29.51％.③ Patients with lung cancer by histopathologic classification,different concentration of tumor classification HSP90 α was no difference (P＞0.05).④Spearman rank correlation analysis showed that HSP90 α levels were positively correlated with CYFRA21-1 (r,=0.44,P＜0.01).The difference was statistically significant (F=14.98,P =0.00).HSP90 α and CEA,NSE,SCC had no relevance.⑤ HSP90 α and CEA,NSE,SCC,CYFRA21-1 the area under the ROC curve (AUC) in the diagnosis of lung cancer were:0.961,0.562,0.731,0.465 and 0.632 best cutoff value were 89.3 ng/ml,6.32 ng/ml,18.63 ng/ml,1.93 ng/ml and 2.36 ng/ml.Sensitivity of 73.49％,52.3％,73.49％,59.6％ and 62.1％,specific degrees respectively.Accuracy of 98.6％,46.3％,66.3％,98.6％ and 46.3％,respectively,88.4％,80.3％,86.9％,87.2％ and 89.2％ of the five joint,the sensitivity of diagnosis of lung cancer and specific degrees respectively 100％ and 75％.Conclusion Using ROC curve analysis showed that HSP90 α plays an auxiliary role in diagnosis of lung cancer,CEA,NSE,CYFRA21-1 and SCC can significantly increase the detection rate of lung cancer.