Radiomics based on arterial-venous mixed images derived from dual-energy CT data in diagnosis of lymph nodes metastasis of papillary thyroid cancer / 中华放射学杂志

Objective:To explore the diagnostic value of radiomics based on arterial-venous mixed images derived from dual-energy CT (DECT) data in diagnosis of cervical lymph nodes (LNs) metastasis of papillary thyroid cancer (PTC).Methods:From June 2017 to December 2018, eighty-four patients with preoperatively DECT scanning and pathologically confirmed PTC (129 non-metastatic LNs and 97 metastatic LNs) in the First Affiliated Hospital of Nanjing Medical University were included in this study. The clinical and imaging data of all patients were retrospectively analyzed. The training cohort consisted of 62 PTC cases with 156 LNs (91 non-metastatic LNs and 65 metastatic LNs). An independent validation cohort consisted of 22 PTC patients with 70 LNs (38 non-metastatic LNs and 32 metastatic LNs). Semi-automatic LNs segmentation was conducted on arterial-venous mixed images derived from DECT using Syngo.via Frontier Radiomics software. Totally 1 226 radiomics features were extracted from arterial-venous mixed images for each LN. The least absolute shrinkage and selection operator (LASSO) regression was applied for radiomics features selection and signature building. The logistic regression modeling was used to construct diagnostic models based on the CT image features of LNs (model 1), the radiomics signature (model 2) and the combination of the CT image features and radiomics signature (model 3). An intuitive nomogram was plotted for model 3. The ROC curve analyses and area under the curve (AUC) were performed to evaluate the diagnostic efficiency of the three models, with the performances compared using the Delong test.Results:Model 1 was developed with LNs shape, degree of enhancement, pattern of enhancement, calcification and extra nodal extension. Three arterial phase radiomics features were selected and used to establish radiomics signature using LASSO regression (model 2). Model 3 was developed with LNs size, shape, degree of enhancement and radiomics signature. In both the training and validation cohort, model 3 showed the best diagnostic performance (AUC=0.965, 0.933), followed by model 2 (AUC=0.947, 0.910), and both these two models significantly outperformed model 1 (AUC=0.850, 0.846) (training cohort, Z=4.066 and 3.758, P both<0.001; validation cohort, Z=2.871 and 1.998, P=0.017 and 0.042) respectively. Conclusion:The radiomics model based on arterial-venous mixed images derived from DECT data can realize effective diagnosis of LNs metastasis in patients with PTC; and the combination model of radiomics signature with CT image features can further improve the diagnostic accuracy.

Collagen Peptides Improve Lymphocyte Distribution in Peripheral Blood and T Lymphocyte Proliferation in Spleen of Mice under the Condition of Simulated Weightlessness / 中国实验血液学杂志

OBJECTIVE@#To investigate whether collagen peptides can improve the immune functions of mice under the condition of simulated weightlessness.@*METHODS@#Mouse tail-suspension model was used to simulate the effects of weightlessness. Tail-suspended mice were intraperitoneally injected with 600 mg collagen peptides per kilogram body weight once a day for 10 days. Then, the mice were killed, and white blood cells were counted and classified. Lymphocyte subsets and T lymphocyte proliferations in spleens were analyzed.@*RESULTS@#Compared with normal control group, total and differential count of leukocytes, lymphocytes, T cells，CD4 and CD8 T cells, B cells and NK cells, and splenic T lymphocyte proliferation all decreased in the weightlessness simulated mice (P＜0.05). Except for NK cells, the above-mentioned parameters were increased after administration of collagen peptides, and some of the parameters were recovered to the levels of normal control mice (P＜0.05).@*CONCLUSION@#Collagen peptides can effectively improve peripheral blood lymphocyte distributions and T lymphocyte proliferations of mice under the condition of simulated weightlessness. This study nay provid the experimental basis for improvement of immune functions of astronauts.

MicroRNAs of bone marrow mesenchymal stem cell-derived exosomes regulate acute myeloid leukemia cell proliferation and apoptosis / 中华医学杂志(英文版)

BACKGROUND@#Acute myeloid leukemia (AML) is a malignant hematological disease, originating from hematopoiesis stem cell differentiation obstruction and clonal proliferation. New reagents or biologicals for the treatment of AML are urgently needed, and exosomes have been identified as candidate biomarkers for disease diagnosis and prognosis. This study aimed to investigate the effects of exosomes from bone marrow mesenchymal stem cells (BMSCs) on AML cells as well as the underlying microRNA (miRNA)-mediated mechanisms.@*METHODS@#Exosomes were isolated using a precipitation method, followed by validation using marker protein expression and nanoparticle tracking analysis. Differentially expressed miRNAs were identified by deep RNA sequencing and confirmed by quantitative real-time polymerase chain reaction (qPCR). Cell proliferation was assessed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt method, and cell cycle progression and apoptosis were detected by flow cytometry. Functional gene expression was analyzed by qPCR and Western blotting (WB). Significant differences were determined using Student's t test or analysis of variance.@*RESULTS@#BMSCs-derived exosomes effectively suppressed cell proliferation (both P < 0.0001 at 10 and 20 μg/mL) and cell cycle progression (P < 0.01 at G0-G1 stage), and also significantly enhanced cell apoptosis (P < 0.001) in KG-1a cells. There were 1167 differentially expressed miRNAs obtained from BMSCs-derived exosomes compared with KG-1a cell-derived exosomes (P < 0.05). Knockdown of hsa-miR-124-5p in BMSCs abrogated the effects of BMSCs-derived exosomes in regulating KG-1a such as the change in cell proliferation (both P < 0.0001 vs. normal KG-1a cell [NC] at 48 and 72 h). KG-1a cells treated with BMSCs-derived exosomes suppressed expression of structural maintenance of chromosomes 4 (P < 0.001 vs. NC by qPCR and P < 0.0001 vs. NC by WB), which is associated with the progression of various cancers. This BMSCs-derived exosomes effect was significantly reversed with knockdown of hsa-miR-124-5p (P < 0.0001 vs. NC by WB).@*CONCLUSIONS@#BMSCs-derived exosomes suppress cell proliferation and cycle progression and promote cell apoptosis in KG-1a cells, likely acting through hsa-miR-124-5p. Our study establishes a basis for a BMSCs-derived exosomes-based AML treatment.

Analysis of adult mosquito monitoring results from 2017 to 2019 in Tongliao City / 上海预防医学

Objective To understand the species composition, density and seasonal variation of adult mosquitoes in Tongliao City of Inner Mongolia Autonmous Region from 2017 to 2019, and to provide scientific data for risk assessment and prediction of mosquito-borne diseases, mosquito-borne control planning, precise implementation and effect evaluation. Methods The density of adult mosquitoes was monitored in parks, hospitals, residential areas, farmers and cattle sheds in Tongliao by using the light trap method. Results A total of 3 358 adult mosquitoes were captured, including Anopheles sinensis, Culex tritaeniorhynchus and Culex quinquefasciatus with Culex quinquefasciatus as the dominant species.The change curve of adult mosquito density with season showed a single peak, and the peak period was from July to September.The density of adult mosquito in cattle shed was the highest (6.71 per night), and that in hospital was the lowest (0.99 per night).The difference between urban and rural areas in seasonal distribution of adult mosquitoes was statistically significant (χ2=4.65, P < 0.05). Conclusion Culex pipiensquinquefasciatus is the dominant mosquito species in the local area, and the villages are the places with high incidence of mosquito infestation.

Advance in Physiological Ischemic Training in Cardiac Rehabilitation (review) / 中国康复理论与实践

The collateral circulation of coronary arteries can improve the cardiac function of patients with coronary heart disease, increase the blood supply of pathological ischemic myocardium, and reduce the mortality. This paper summarized the physiological ischemic training for coronary collateral circulation formation.

A new protecting method for the inferior parathyroid gland in situ: the meticulous thyrothymic ligament dissection technique / 中华内分泌外科杂志

Objective To explore the anatomical features and the dissection technique of thyrothymic ligament (TTL),and to explore the clinical significance of protecting the inferior parathyroid gland (IPTG) with this structure.Methods Patients who received the initial thyroid surgery in the Department of Thyroid Surgery of the First Affiliated Hospital with Nanjing Medical University from May.2017 to Dec.2017 were prospectively analyzed.We dissected TTL,identified and located the IPTG,described the structural features of TTL,and investigated the position relationship of TTL and IPTG to evaluate the possibility and value of protecting IPTG in situ.Results About 121 patients underwent the dissection,totally 194 sides dissected that included 96 left sides and 98 right sides.TTL was found in 143 sides (73.7％),78 left sides (81.3％) and 65 right sides (66.3％).Nearly 70.6％ IPTG can be proactively identify and located by the TTL during the operation.TTL was a kind of adipose connective tissue that was wide at the bottom and narrow at the top,accompanying with the inferior thyroid vein,from the thymus to the thyroid.76.2％ TTL were attached to the lower pole and the lower 1/3 dorsal of thyroid,containing fat and vessels.33.5％ IPTGs were located in the area surrounding around the ends of the TTL.25.3％ IPTGs were located in the TTL.4.6％ IPTGs were located in the thymus and 7.2％ IPTGs surrounding around the TTL.The incidence rate of post-operation hypoparathyroidism was 14.9％.Conclusions TTL commonly exists and has significant relationship with IPTG.TTL connects thymus and IPTG,which would be considered a complex (thymus-thyrothymic ligament-IPTG complex,TLIC).The meticulous TTL dissection technique will help proactively identify,locate and protect IPTG during operation,and reduce the incidence rate of post-operation hypoparathyroidism.

The value of individualized contrast agent injection regimen in coronary CTA imaging based on body surface area and body weight / 解放军医学杂志

Objective To explore the effect of individualized contrast agent injection regimen on coronary artery enhancement based on body surface area (BSA) and body weight (BW).Methods Totally 300 patients with suspected coronary heart disease from January to December 2016 in our hospital were randomly divided into three groups:control group (the injection volume and flow rate were fixed),BSA adjustment group and BW adjustment group.The patients were detected by CTA,and the degree and quality of coronary artery enhancement,the amount and flow rate of contrast agent,and the safety were analyzed in the three groups.Results The coronary artery enhancement value of the BSA adjustment group and the BW adjustment group was significantly higher than that of the control group (P＜0.05).The coronary enhancement in the BSA adjustment group was significantly higher than that of the BW adjustment group.Moreover,the standard deviation of the BSA adjustment group was significantly lower than that of the BW adjustment group (P＜0.05).The CTA score of the BSA adjustment group was significantly higher than that of the control group (P＜0.05).However,there was no significant difference between the BW adjustment group and BSA adjustment group or the control group (P＞0.05).The contrast agent dosage and flow rate was significantly higher in the control group than in the BSA adjustment group and BW adjustment group (P＜0.05).However,there was no significant difference between the BW adjustment group and BSA adjustment group (P＞0.05).Also,there was no significant difference in safety index between the three groups (P＞0.05).Conclusion The individualized contrast agent injection program based on BSA adjustment could not only reduce the amount of coronary imaging contrast agent and flow rate,but also improve the degree and effect of coronary artery enhancement.It could be expected to become a technical means for screening,early diagnosis,and even early intervention in early coronary heart disease.

The short-term efficacy of Crowe Ⅳ developmental dysplasia treated by total hiparthroplasty with subtrochanteric shortening osteotomy / 重庆医学

Objective To evaluate the short-term efficacy of total hip arthroplasty combined with subcutaneous osteotomy in the treatment of CroweⅣ hip dysplasia (DDH).Methods From March 2012 to March 2015,14 patients (16 hips) underwent total hip arthroplasty with femoral distraction osteotomy S-ROM femoral stem prosthesis.And we observed its recent efficacy.Results All patients underwent S-ROM prosthesis.The patients underwent transverse osteotomy of the femoral trochanter.The osteotomy length was 2.0-3.5 cm.The average follow-up time was 19 months.And no complications such as dislocation,vascular nerve injury,deep vein thrombosis and infection were observed during the follow-up.The average Harris scores improved from 42.3 preoperatively to 90.4 postoperatively at 9 months after the operation.The average lengths of preoperative limb shortening and postoperative limb shortening were 6.4 cm and 4.3 cm respectively.The X-ray films showed no dislocation of acetabulum and femoral prosthesis.Bone healing was achieved at 6 months after osteotomy.Conclusion This method could be a good choice for Crowe Ⅳ developmental dysplasia.The short-term efficacy is satisfactory.

Comparisons and reference of dental education between the United Kingdom and China / 中华医学教育探索杂志

Dental education in United Kingdom has been amongst the best in the world with years of experience.General Dental Council (GDC) is the sole competent authority for dentistry in the UK.GDC produces guidance on dental education and lead the inspections and monitoring for dental schools.Postgraduate Dental Deans are responsible for the provision and quality management of the education and training of dental graduates during 2 years' foundation training and 3-5 years' specialty training.There are similarities between UK dental education system and Chinese system in school education and continuing education.It is worthy of reference for the dental education in China in terms of the training system of dental residents and specialists in the United kingdom.

Utilization of dental services for children: a review of the influencing factors and the possible improvements / 中华口腔医学杂志

It has been reported that children's oral health conditions are correlated with their attendance to dental health services. Evaluating the influencing factors of utilization of dental services for children may give ways to improve the services per se, and furtherly the children's oral health. The present review retrieved and summarized domestic and foreign studies on the utilization of oral health services for children based on the Andersen behavior model. It was concluded that the utilization of dental services for children was affected by demographic characteristics, social structure, health belief, family factors, community factors and perceived/evaluated needs. To improve the utilization of dental services for children, effort should be made by means of changing caregivers' health belief, developing oral health insurance system, setting up regular oral health resources and increasing the financial support for oral health services by government.

Analysis of the influencing factors of strain ratio in diagnosing thyroid nodules of thyroid imaging reporting and data system 4-6 categories / 中华医学超声杂志（电子版）

Objective To analyze the influencing factors of strain ratio in diagnosing thyroid lesions of thyroid imaging reporting and data system (TI-RADS) 4-6 categories, and explore the application value of elastic strain ratio in differentiating malignant thyroid nodules from benign ones under different influencing factors.Methods A retrospective analysis was made on the pathologic data of 278 nodules undergone TI-RADS ultrasonography stratification and ultrasound elestography, and 105 nodules of TI-RADS 4-6 categories were selected as research objects. A receiver-operating characteristic (ROC) curve was used to identify the cut-off point for differential diagnosis of thyroid nodules. A logistic regression model was established to analyze the factors affecting strain ratio in the differential diagnosis on thyroid nodules of TI-RADS 4-6 categories. Analyses were made in groups to judging the sensitive, specificity, accuracy, positive predictive value and negative predictive of strain ratio under the impact of different factors. Results The best cut-off point of ROC curve for benign and malignant nodules was 0.54. It was found through the logistic regression model that the strain ratio value was closely related to the size, calcification, and thyroid diffuse disease, and strain ration was of higher value in the thyroid nodules which were less than 1 cm without calcification and thyroid diffuse disease.Conclusions Three factors including size, calcification, and diffuse lesions of the thyroid nodules can influence the elastic strain ratio of TI-RADS 4-6 thyroid nodules. Comprehensive analysis of these three influencing factors can improve the application value of elastic strain ratio in differential diagnosis of benign and malignant thyroid nodules.

Value of ultrasound-guided fine needle aspiration biopsy in diagnosing thyroid nodules of TI-RADS 4-6 categories / 中华超声影像学杂志

Objective To explore the application value of ultrasound-guided fine needle aspiration biopsy(FNAB) in diagnosing thyroid nodules of TI-RADS 4-6 categories.Methods A retrospective analysis was made on the pathologic data of 494 patients (totally 501 nodules) who underwent TI-RADS ultrasonographic stratification and ultrasound-guided FNAB.168 thyroid nodules of TI-RADS 4-6 categories were selected from 163 patients and classified into three groups:group T,TI-RADS 4A categories;group Ⅱ,TI-RADS 4B category; group Ⅲ,TI-RADS 5-6 category(the pathologically confirmed cases in category 6 had been removed).The ultimate pathologic findings were taken as golden standards to calculate the accuracy,sensitivity,specificity,positive predictive value of ultrasound-guided FNAB in the three groups.ROC curve was drawn to evaluate the diagnostic value of FNAB.Results The accuracy,sensitivity,specificity,positive predictive value of the ultrasound-guided FNAB in the three groups were listed as follows:group Ⅰ 74.4％,73.3％,75.0％,64.7％;group Ⅱ 83.9％,87.5％,71.4％,91.3％;group Ⅲ 89.3％,91.7 ％,75.0％,95.7 ％ respectively.The positive predictive values of the ultrasound-guided FNAB for group Ⅰ and group Ⅱ was higher than that of conventional TI-RADS classification criteria,so the difference was statistically significant; while the positive predictive values for group Ⅲ was close to the conventional ultrasound TI-RADS classification criteria,the difference was not statistically significant.Conclusions The combination application of TI-RADS classification criteria and FNAB can improve the accuracy of ultrasound diagnosis in group Ⅰ and group Ⅱ,and reduce the puncture rate of group Ⅲ.

Molecular epidemiology of Mycobacterium tuberculosis in Gansu province of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) and Beijing family typing based on detecting the deletion of RD105 sequence are two common genotyping methods used to study the molecular epidemiologic characteristics of Mycobacterium (M.) tuberculosis. We collected 218 strains of M. tuberculosis between 2004 and 2006 in the Linxia Hui Autonomous Prefecture of Gansu province in Northwest China.</p><p><b>METHODS</b>MIRU-VNTR analysis and Beijing family typing based on detecting the deletion of RD105 sequence were used to type the 218 strains, and their typing power was evaluated to look for practical and efficient genotyping methods suitable for the region.</p><p><b>RESULTS</b>The MIRU typing yielded 115 distinct genotypes, including 98 unique isolates and 17 different clusters containing 120 isolates (55.05%); the cluster rate was 47.25%. By detecting the deletion of RD105 sequence, 188 of 218 (86.23%) isolates belonged to Beijing family. Combination of Beijing family typing and MIRU typing yielded 118 distinct patterns, including 101 unique isolates and 17 clusters containing 117 isolates (54.13%). The largest cluster contained 58 strains with MIRU genotype of 223325173533 which contained 50 strains belonging to Beijing family and 8 strains belonging to non-Beijing family.</p><p><b>CONCLUSIONS</b>The Beijing family strains occupied a large proportion and the Beijing family MIRU genotype 223325173533 is a dominant strain in Linxia of Gansu. Combining detecting the deletion of RD105 and MIRU typing together provides a simple, fast, and effective method which is low in cost and might be practical and suitable for M. tuberculosis genotyping in China.</p>

A study on adequate margine of mastectomy of breast cancer in breast-conserving surgery / 中华普通外科杂志

ObjectiveTo study the scope of excison in breast-conserving surgery for breast carcinoma.MethodsClinical data of 275 breast cancer patients undergoing breast-conserving surgery in t he First Affiliated Hospital of Nanjing Medical University,the Affiliated Zhenjiang Hospital of Jiangsu University and Changzhou Traditional ChineseMedicine Hospital were retrospectively analyzed.The operation procedure and postoperative adjuvant therapy were carried out with the same protocol.Local and general conditions of patients were followed up regularly.Results271 out of 275 patients got follow-up.The follow-up rate was 98.5％.The follow-up time ranged from 1 month to 117 months,median follow-up time was 34 months.Six patients died of distant metastasis,2 with local recurrence.The 1-year,3-year,and 5-year overall survival rates were 99.5％,98.1％,and 95.7％,respectively.ConclusionsIt is safe to excise 1 cm normal breast tissue with clear margin confirmed by frozen section,followed by postoperative adjuvant therapy,endocrine therapy,and radiotherapy,this improves the life quality of patients with breast cancer.It is safe and effective to determine whether the disease is multicentric or multifocal by mammogram plus clinical breast examination.

Effect of insulin-like growth factor on the proliferation and early stage osteogenesis of human periodontal ligament stem cells under three-dimensional culture system / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of insulin-like growth factor-I (IGF-I) on the proliferation and osteogenesis of human periodontal ligament stem cells (hPDLC) under three-dimensional (3D) culture system.</p><p><b>METHODS</b>Human periodontal cells were isolated from the ligament of surgically extracted human teeth, and through the limiting dilution assay, got mono-clone of the cell, hPDLCs were isolated from MesenPRO RS medium. Rotary cell culture system (RCCS) was enrolled to set 3D environment. Control group and experiment groups were assigned according to the concentration of IGF-I. There were 5 level of experiment groups (0.1, 1, 10, 50, 100 µg/L). Proliferation was tested with methyl thiazolyl tetrazolium (MTT), and alkine phosphatase (ALP) level was assayed by spectrophotometer to analyze the osteogenesis of hPDLCs. Gene expression of ostetocalcin (OCN) and type I collagen (Col I) were assayed by reverse transcriptase polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>In 3D culture system, the effect of IGF-I on cell proliferation was significantly different between control group and experiment groups (P < 0.05), and there showed significant differences between the group of 0.1 µg/L (0.219 ± 0.021) IGF-I and the groups of 50, 100 µg/L (0.287 ± 0.011, 0.293 ± 0.012). However, there showed no significant differences among other groups. Significant differences of ALP activity were observed between the control group and experiment groups, and between the groups of 1, 10 µg/L (0.304 ± 0.020, 0.310 ± 0.013) and that of 50, 100 µg/L (0.347 ± 0.011, 0.344 ± 0.010) (P < 0.05). While no significant differences were detected between the group of 1 µg/L and that of 10 µg/L, nor between the group of 50 µg/L and that of 100 µg/L. Expressions of Col I and OCN in mRNA and protein level both showed dose-dependent increase.</p><p><b>CONCLUSIONS</b>In 3D culture system, in the scale of 0.1 - 100 µg/L, the effect of IGF-I on the proliferation of hPDLCs increased dose-dependently. 100 µg/L IGF-I promotes osteogenesis of the cells significantly.</p>

Oral health services utilization and influencing factors in downtown community residents older than 15 years in Beijing / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the utilization of oral health services and to analyze the factors associated with oral health services for the community residents.</p><p><b>METHODS</b>Household health interview and oral health condition survey were conducted to obtain information about oral health services. The respondents were recruited by a multi-stage random cluster sampling procedure. Multiple dummy regression analyses were performed for the assessment of the relative effect of behavioural factors on dental attendance.</p><p><b>RESULTS</b>A total of 2003 families, 4459 people participated in this study. The people seeking dental treatment accounted for 11.3% (502/4459) per year. Young people (OR = 2.072), having medical insurance system (OR = 2.835), short distance to see dentist (OR = 3.535), oral health awareness (OR = 2.595), poor self-assessment of oral health status (OR = 2.014) were the main factors which influenced dental attendance of community residents.</p><p><b>CONCLUSIONS</b>The utilization of oral health service was low, particularly for middle-aged people and the elderly. Oral health education and medical insurance system should be strengthened.</p>

The effect of insulin-like growth factor-I on the proliferation and alkaline phosphatase activity of human periodontal ligament cells under three-dimensional culture system / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of insulin-like growth factor- I (IGF- I) on the proliferation and alkaline phosphatase (ALP) activity of human periodontal ligament cells (hPDLCs) under three-dimensional (3D) culture system.</p><p><b>METHODS</b>The hPDLCs were cultured from periodontium of human teeth by the outgrowth method. Rotary cell culture system (RCCS) was enrolled to set 3D culture system. Samples were set to four groups: Negative control group, positive control group (3D group, IGF-I group), and experimental group (3D with IGF- I group). Proliferation was tested with methylthiazolyl tetrazolium (MTT), and ALP activity was assayed by spectrophotometer at 1, 3, 5, 7 d respectively.</p><p><b>RESULTS</b>Compared with that of negative control group, cell proliferation increased significantly in 3D with IGF-I group since 3 d (P < 0.05). Besides, the cell proliferation of 3D with IGF-I group was significantly higher than that of 3D group (P < 0.05). ALP activity of 3D with IGF- I group was significantly higher than that of negative control group, and 3D group at 3, 5, 7 d (P < 0.05).</p><p><b>CONCLUSION</b>IGF-I significantly promotes the proliferation and ALP activity of hPDLCs under 3D culture system.</p>

Primary study of the relationship between periodontitis and COPD / 实用口腔医学杂志

Objective:To explore the relationship between Chronic Obstructive Pulmonary Disease (COPD) and periodontitis. Methods: 498 subjects were recruited in this study and were divided into three groups: mild periodontitis group (77, 15.5%), moderate periodontitis group (143, 28.7%), and severe periodontitis group (278, 55.8%). Clinical examination indexes included probing depth (PD), attachment loss (AL), sulcus bleeding index (SBI), plaque index (PLI) and the level of the alveolar resorption. Lung function of each subjects were also examined. Results: The levels of AL, PLI and alveolar resorption in COPD group were higher than non-COPD group. Significant differences of "FEV1% pre"(F=3.59,P=0.028) and "FEV1/FVC"(F=4.84,P=0.008) were found among different degrees of periodontitis. Negative relationship was found between the level of "FEV1% pre" and the periodontal index (AL, PLI, alveolar resorption), and the same relationship was found for "FEV1/FVC". Conclusion: Correlation is found between COPD and the periodontitis index (AL, PLI, alveolar resorption).

Community diagnosis of dental caries in an urban community of Beijing / 中华全科医师杂志

Total 1188 subjects aged 35-74 in an urban community of Beijing were recruited by a multistage stratified random sampling procedure. Dental caries were examined by three dentists independently. The prevalence of dental crown caries was 79. 6% (DF), that of DMFS was 24. 39% and the root caries index (RCI) was 3.5% in this group. 22. 3% of the examinees required treatment for the crown caries and 26. 0% for root caries. Bivariate correlation analysis showed that DMFS was significantly correlated with RCI (P <0. 01 ), and there was no significant difference of DMFS and RCI between males and females. The study indicates that dental caries is a common health problem in adults and elderly population of urban Beijing, and the development of community oral health service system is necessary.

Research advances in aspirin resistance / 中国医学科学院学报

Aspirin is an important antithrombotic agent. However, its clinical benefit is impaired by aspirin resistance. The term of "aspirin resistance" usually refers to laboratory resistance. It can be identified by measuring thromboxane A2 or thromboxane-dependent platelet function. Clinical trials have shown that laboratory aspirin resistance is correlated with vascular events.