The anaerobic threshold (AT) and maximal oxygen uptake (VO_(2max)) are both important physiological foundation of the aerobic capacity for athletes. The purpose of this study was to evaluate the cross-country skiers' aerobic capacity comprehensively and to provide useful information for selecting and training skiers by using the AT and VO_(2max). The results showed that there were significant differences between men's VO_(2max) (4.4L/min, 69.09 ml/kg. min and VO_(2AT) (2.89 L/min) and women's (3.071/min, 55.33 ml/min for VO_(2max) and 2.03 L/min for VO_(2AT), respectively) (p

Designed experiment in medical functional experiment has become an important way to promote creative thinking and innovation of medical students.We applied different modes of designed experiment in undergraduates of clinical medicine and basic medicine in capital medical university,including classroom designed experiments,proposition designed experiments and free proposition designed experiments.After above reforming implements,creative thinking and innovation ability of medical students were enhanced.It also provided new ideas in future teaching reform in functional experiment.

Objective To research the effect of molecular chimeric mice pre-T cells on proliferation ability of allogeneic mouse T cells.Methods The MHC-Ⅰ gene (H-2Kband H-2Db gene) were extracted and amplified by RT-PCR,the identified pre-T cells were transfected by the constructed eukaryotic expression vector of C57BL/6mouse MHC-I (pIRES-H-2Db and pIRES-H-2Kb),non-transfected group and sham pIRES-transfected control group were set.The molecular chimeric cells were transfused back to BALB/c mouse.After 7 days,T lymphocyte cells of each group were extracted,the ability of molecular chimeric cells inducing spleen T lymphocyte response to allogeneic T cells was observed through mixed lymphocyte culture (MLC).Results Sequencing of the plasmid we have constructed showed that insertion sequence contained C57BL/6 mice H-2Kb and H-2Db series which could be retrieved from GenBank.The result of flow cytometry analysis indicated that H-2Kb and H-2Db protein had an increased expression in pre-T cells,the difference with other two groups was statistically significant (P＜0.05).The result of MLC demonstrated that the stimulation index (SI) of T lymphocyte in co-injection transfected pIRES-H-2Kb and pIRES-H-2Db pre-T cells group (0.764±0.074) were significantly decreased compared with non-transfected group(0.983±0.081)and sham pIRES-transfected group(0.994±0.142) (P＜0.05).Conclusions The molecular chimeric pre-T cells infusion can reduce spleen T lymphocyte response to allogeneic T cells and it may induce immune tolerance in vivo.

Objective:To analyze the usage intention and key issues of medical staff to use telemedicine, for improving telemedicine service system in China.Methods:From October to November 2019, medical workers of both the inviting party and invited party who experienced telemedicine in seven provinces of Fujian, Hainan, Henan, Hunan, Guizhou, Sichuan and Qinghai were selected for an online questionnaire survey. Areas covered included their usage intention, satisfaction and cognitive appraisal of telemedicine. Descriptive statistical analysis and non-parametric test were used to discuss the intention of further use, satisfaction and challenges of medical workers in various provinces and regions.Results:1 084 valid questionnaires were recovered. The data found the overall satisfaction was 98.62%, and the proportion of their intention of further use was 98.25%, and those from the eastern and western provinces presented higher intention of usage. The top challenges as reflected by these medical workers were named as follows: timeliness of consultation progress and information feedback; long latency time; low Internet speed, poor and interrupted Internet signal; inadequate system equipments and inconvenient operation; difficulties in remote physical checkup and overall understanding of patient conditions; as well as substandard, incomplete and poor medical records.Conclusions:These medical workers are satisfied with the telemedicine services and willing to continue to use telemedicine.For those existing problems, it is suggested to strengthen the infrastructure and optimize the process of telemedicine services, so as to encourage them in greater use of telemedicine.

Objective:To analyze the actual and expected incentives and key issues of telemedicine providers in China and to provide important references for optimizing telemedicine incentive policies.Methods:The sample data came from a questionnaire survey of 1 084 providers in 7 provinces of Fujian, Hainan, Henan, Hunan, Guizhou, Sichuan and Qinghai in October and November 2019 and a semi-structured interview data at 6 hospitals in Henan province in January 2020. Descriptive analysis was used to sort such data into text data for classified summation.Results:The greatest gaps were found between actual incentives and expected ones in expense subsidies, title promotion and excellence awards, with such gaps as high as 18.65, 28.26, 29.28 percentages among providers of junior, deputy senior and senior academic titles respectively. Hospitals fall short in providing adequate incentives for telemedicine providers, not to mention lack of differentiation and diversification in personnel incentives, and poor implementation of incentive policies.Conclusions:It is suggested to strengthen incentive demand analysis, break the homogenization bottleneck of incentive policies, and consolidate internal publicity and implementation of incentive policies.

Objective To investigate the feasibility and accuracy of enhanced magnetic resonance pulmonary perfusion imaging(MRPP) in the diagnosis and follow-up of pulmonary embolism(PE). Methods Sixty patients suspected of PE underwent MRPP. Twenty-seven patients also underwent radionuclide perfusion imaging. 22 patients repeated MRPP examination after 3 day to 1 month anticoagulation or thrombolytic therapy. The feasibility and accuracy of MRPP in the diagnosis and follow-up of PE were evaluated according to the transformation rate of signal (TROS), time-signal curve and some parameters of main pulmonary artery(such as peak value of flow,mean flow velocity and flow rate). The t test and rank sum test were used for the statistics. Results MRPP showed a high agreement with radionuclide perfusion imaging. TROS was (2. 86 ± 2. 48 ) vs ( 6. 72 ± 2. 54) ( t = 3. 370, P ＜ 0. 01 ), the peak time was ( 13.98 ±5.60) vs ( 12. 33 ± 3.63 ) s ( t = 3. 930, P ＜ 0. 01 ), the peak value of main pulmonary blood flow was (60.39 ± 15. 17) vs (69.93±13.22) cm/s(t=2.930, P＜0. 01) and mean flow velocity (11.68±5.46) vs ( 13.54 ± 4. 18 ) cm/s ( t = 2. 380, P ＜ 0. 05 ) before and after anticoagulation or thrombolytic therapy. The flow rate per unit was (80. 57 ± 24. 87) vs ( 85.48 ± 11.81 ) ml/s ( t = 0. 86,P ＞ 0. 05 ) . Conclusion MRPP shows a high agreement with radionuclide perfusion imaging and is a useful method for the diagnosis and follow-up of PE.

Objective To discuss the clinical application of reverse dorsal metatarsal artery perforator flap for reconstruction of forefoot soft tissue defects.Methods Since January,2008 to March,2016,43 patients with forefoot soft tissue defect due to various causes were reconstructed with the flap based on dorsal metatarsal artery perforator.Dorsal pedis was used as a donor site with dorsal metatarsal artery perforator as the donor artery.The flap size varied from 2.0 cm × 4.0 cm to 6.0 cm × 8.0 cm.Among them,27,8,4 and 4 cases were reconstructed with flap based on first,second,third and fourth dorsal metatarsal artery perforator flap respectively.Results All the patients were followed-up which ranged from 3 months to 24 months.Six flaps suffered from post operative venous congestion.Out of 6,4 survived with early emergency management while the remaining 2 suffered epidermal necrosis which survived with regular dressing change.Eventually,all the flaps survived.They had good texture and they were elastic,good-looking and very wear-resisting.Walking function was normal.Conclusion Reverse dorsal metatarsal artery perforator flap is an ideal choice in reconstruction of small to medium sized soft tissue defects of forefoot.

Objective To explore the feasibility of delineation of the atherosclerotic plaque in carotid artery using compressed sensing three dimensional motion-sensitized driven equilibrium prepared rapid gradient echo (CS-3D MERGE) technique. Methods Twenty-three patients who underwent carotid endarterectomy (CEA) were enrolled prospectively. In all patients, bilateral carotid arteries were scanned by CS-3D MERGE and contrast-enhanced MR angiography (MRA) simultaneously. Image quality of CS-3D MERGE images was scored. Images from the CS-3D MERGE sequence and contrast-enhanced MRA were used to measure the carotid stenosis, which were divided into four groups:normal group, mild stenosis group, moderate stenosis group, and severe stenosis group. The results were compared between the two methods. And images from the CS-3D MERGE sequence were compared with corresponding histology in identifying major plaque components including lipid rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and calcification (CA). Spearman rank correlation coefficient was used to compare the correlation between the CS-3D MERGE sequence and contrast-enhanced MRA in measuring the carotid stenosis. Agreement was tested comparing images from the CS-3D MERGE sequence with corresponding histology in identifying major plaque components including lipid-rich necrotic core, intraplaque hemorrhage, and calcification. Results Twenty-three CEA patients finished bilateral CS-3D MERGE scanning successfully. Image quality was 3.16±0.25. There was an excellent correlation between CS-3D MERGE and MRA in measuring stenosis (r=0.95, P<0.01). The agreement between CS-3D MERGE and histological results for LRNC detection was 76.2% (16/21). It was less sensitive for IPH detection (71.4%, 15/21). CS-3D MERGE identified all CA accurately (100.0%, 21/21). Sensitivity and specificity were 86.6% (13/15) and 50.0% (3/6) for LRNC, 73.3% (11/15) and 66.6% (4/6) for IPH, 100.0% for CA respectively(16/16, 5/5). Conclusion CS-3D MERGE, a single sequence, can be used to quantify carotid stenosis and plaque components conveniently.

PurposeTo determine the feasibility and accuracy of dual source CT (DSCT) in assessing myocardial delayed-enhancement and left ventricular wall thickness of hypertrophic cardiomyopathy (HCM) in comparison with cardiac magnetic resonance (CMR).Materials and MethodsEighty patients with HCM confirmed by clinical diagnosis were enrolled in the study. DSCT images and CMR images were acquired at the arterial and lag phases. According to 17-segment model provided by American Heart Association, the left ventricular wall thickness and location of delayed-enhancement were verified, and the correlation of these two methods were analyzed in terms of the diagnosis of myocardial delayed enhancement (MDE).Results1360 myocardial segments for 80 patients were assessed. The left ventricular wall thickness determined by DSCT was significantly correlated with MR results (r=0.88,P<0.01). DSCT and MDE showed substantial agreement on per-patient (n=74,Kappa=0.751,P<0.05) and per-segment (n=1238, Kappa=0.746,P<0.01) levels. For dense myocardial delayed enhancement, CT findings were significantly correlated with those of CMR (r=0.89, P<0.01), but CT scan slightly underestimated the lesion scope of fibrosis. Bland-Altman analysis showed that CT and MRI were different in measuring the lesion volume of myocardial delayed enhancement (mean standard deviation was 2.71%).ConclusionThe cardiac CT examination provides comprehensive information in coronary artery and myocardial assessment, and MDE-DSCT is also effective in the diagnosis of myocardial fibrosis in HCM since it can be used in assessing myocardial fibrosis.