Rheumatoid arthritis (RA) is a systemic autoimmune disease with unknown etiology.The main feature of RA is chronic,symmetrical and invasive arthritis.RA may present with severe joint deformity and functional loss,which has higher disability and fatality rates.At present,no effective measures can reverse bone damage associated with RA clinically.Therefore,early diagnosis of RA is critical to improve prognosis.In recent years,imaging increasingly plays an important role in the early diagnosis of RA.This article reviews recent advances in imaging methods for early diagnosis of RA.

The Chinese clinical medical national licensing examination is the profession ad-mittance exam, which is undertake the responsibility of selecting qualified physicians. It also promotes the medical education in China. The standard for examination, the examination content, methods for measuring the Chinese clinical medical national licensing examination as well as the reform and de-velopment, has a certaln guiding role to China's medical education and medical education reform. While reviewing the medical students' performance in the examination, we can discover the weakness in medical education, which is then conducive to the promotion of teaching reform and innovation. The competence based medical licensing examination reform in China, advocating the cultivation of clinical comprehensive ability as the core content to tralning and evaluating, is conducive to continuously im-proving the quality of medical education in China, and to tralning more qualified physicians in the country.

Objective To observe the effect of electrical stimulation on the movement of rabbits esophagus, and to promote effective esophageal peristalsis and determine the best electrical pacing parameters. Methods After anesthesia, 24 healthy rabbits underwent open surgery and the lower esophagus was exposed. The esophagus was stimulated with the multi-channel signal generator, and the changes of esophagus pressure and the length of esophageal contraction with high resolution manometry were recorded. (1) The effects on contraction pressure of esophagus body and lower esophageal sphincter (LES) after single site electrical stimulation under different parameters were observed. The stimulation modes utilized were electric current 3 mA, 5 mA and 8 mA, frequency 5 Hz, 10 Hz and 20 Hz, pulsewidth 0. 25 ms, 25 ms and 50 ms, waveform of single phase and double phase. (2) The esophagus was sequentially stimulated. The stimulation mode utilized was electric current 5 mA, frequency 20 Hz, pulsewidth 25 ms, stimulation duration 3 s, single phase square wave. Results At electrical stimulation on the esophagus body and LES, contraction delay was 13. 00±1. 54 ms and 12. 00±0. 73 ms respectively. The contraction pressure of esophageal body was significantly positively related tothe electric current (R=0. 968, P<0. 01), the pulse width(R=0. 971, P<0. 01), and the frequency (R =0. 947, P <0. 01). The length of contraction in 10 Hz group was shorter than that of the 20 Hz group(1. 33±0. 06 cm VS 1. 80±0. 00 cm, P<0. 05). The contraction pressure of LES was also significantly positively related to the electric current(R=0. 965, P<0. 01),the pulse width (R=0. 973, P<0. 01), and the frequency (R=0. 842, P<0. 01). The pressure of lower esophageal sphincter of single phase square wave was greater than that of the double phase square group (P<0. 05). Under the same parameters, the contraction pressure of LES group was lower than that of the esophageal body group (27. 33±1. 15 mmHg VS 104. 00±6. 00 mmHg, P<0. 05). Esophageal sequential contraction was induced by multi-points sequential electrical stimulation. Conclusion Single point electric stimulation can cause esophageal contraction immediately without obvious delay. Within a certain range, the esophageal contraction pressure is positively correlated with electric current, frequency and pulse width. The contraction pressure of single square phase wave is greater than that of the double square phase wave. The contraction pressure of esophageal body is greater than that of LES after electric stimulation. Multi-points sequential electrical stimulation can promote sequential movement of esophagus.

Objective To study the anatomic features of surface vasa vasorum on longissimus in thoracolumbar segments,and its protection function during the internal fixation for thoracolumbar fracture via Wiltse approach.Methods From March 2010 to October 2012,a total of 97 patients with thoracolumbar fractures underwent posterior internal fixation with pedicle screw system.The trend and distribution of surface vasa vasorum on longissimus in thoracolumbar segments were observed in the operation,and the vessels were protected during the surgical procedures by using specific devices and techniques.Operative time and intra-operative blood loss were recorded.Visual analogue scale (VAS) values were evaluated after 3 days,1 month,6 months postoperatively,and 1 month after the removal of internal fixation.MRI images of longissimus in thoracolumbar segments were compared after preoperative and postoperative 6 months.Results Surface vasa vasorum distribution on 194 longissimus and 402 inter-pedicle areas of 97 patients were observed.In 402 areas,94.3％ of surface vasa vasorum presented sarciniform,while only 5.7％ of surface vasa vasorum presented tube shape.In 379 areas of sarciniform distribution,9.8％ of blood vessel bundles were located in vertebral pedicle area;76.0％ of blood vessel bundles were located in the upper inter-pedicle areas;12.4％ of blood vessel bundles were located in middle inter-pedicle areas;1.8％ of blood vessel bundles were located in lower inter-pedicle areas.In 379 areas,87.3％ of blood vessel bundles could be completely retained;12.7％ of blood vessel bundles were treated by electro coagulation and burning.Intra-operative blood loss was 21±9.3 ml.VAS values after 3 days,1 month,6 months postoperatively,and 1 month after the removal of internal fixation were 3.3± 1.6,2.1± 1.4,1.2±0.7 and 1.1±0.7.The longissimus treated with electro coagulation demonstrated pimelosis change on MRI after postoperative 6 months.Conclusion Surface vasa vasorum on longissimus in thoracolumbar segments are generally of sarciniform,and most of them are located in upper inter-pedicle areas.The protection of vasa vasorum can reduce the intra-operative lesion and postoperative pimelosis change of longissimus.

Objective To study the effect of precise locating technique of C?arm fluoroscopy in order to reduce the radia?tion exposure during the surgical procdure for thoracolumbar fracture. Methods From March 2010 to Octorber 2012, a total of 92 cases with thoracolumbar fracture underwent postierior internal fixation procdures with pedicle instrumentation. C?arm fluoros?copy was used in 44 cases with precise locating technique, while in 48 cases with traditional methods. In precise locating group,C?arm fluoroscopy was used after anesthesia. Once an ideal view was got, the position parameters of C?arm fluoroscopy machine were recorded. The machine was positioned according to the recording for the secondary fluoroscopy. Pre?operative and intra?operative number of times of exposure, length of exposure time, time for fluoroscopy and total operating time were recorded and compared be?tween two groups. Results Pre?operative number of times of exposure, exposure time, and time for fluoroscopy in precise locating group were (5.51±2.47), (2.26±1.05) s and (9.83±3.67) min,which were higher than those of (4.02±2.42), (1.78±0.98) s and (8.29± 3.52) min in traditional group. However, intra?operative number of times of exposure, exposure time, and time for fluoroscopy in precise locating group were (5.26±3.64), (2.24±1.24) s and (10.39±4.82) min,which were lower than those of (9.74±4.38), (4.21± 2.38) s and (24.69±6.35) min in traditional group,and total number of times of exposure, exposure time, time for fluoroscopy and total operating time in precise locating group were(10.77±4.16), (4.50±1.83) s, (20.22±5.03) min and(70.52±18.33)min,which were also lower than those of (13.76±5.31), (5.99±3.27) s , (32.98±7.83) min and(81.86±21.57)min in traditional group. Conclu?sion Precise locating technique of C?arm fluoroscopy reduces the radiation exposure during the surgical procdure for thoracolum?bar fracture.

Objective To examine the expression of CD9 protein in pancreatic cancer tissues and adjacent tissues,and to analyze its relation with the progress and prognosis of pancreatic cancer.Methods From September 2005 to December 2009,surgical resected cancer tissues and adjacent tissues of 90 patients with pancreatic cancer and their clinical data were collected.The expression of CD9 protein in pancreatic cancer tissues and adjacent tissues was detected by immunohistochemistry,and its relationship with clinicopathological features was analyzed.Chi-square test was performed for comparison of ratios between groups.Overall survival (OS) analysis of 90 patients after surgery was performed.Results The high expression rate of CD9 protein (64.4％,58/90) in cancer tissue was significantly higher than that in cancer adjacent tissue (45.6％,41/90),the difference has statistically significant (χ2 =6.847,P＜0.05).CD9 protein was highly expressed in most of pancreatic cancer tissue which was well differentiated or without lymph node metastasis (74.6％ (50/67) vs 39.1％ (9/23),χz =9.554,P＜0.01; 50.0％(17/34) vs 73.2％(41/56),χ2 =5.856,P＜0.05 respectively).However,the expression of CD9 was not correlated with gender and age (both P＞0.05).OS and progression-free survival (PFS) of the patients with CD9 highly expressed were significantly longer than those with low expression of CD9 (median OS:33.0 months vs 7.0 months,χ2 =15.400 P＜0.01.Median PFS:30.5 months vs 5.0 months,χ2 =13.750,P＜0.01).Conclusion CD9 protein is a kind of protein related with the invasive ability of pancreatic cancer,which may play a role in progression and metastasis of pancreatic cancer and can help to determine the prognosis to a certain extent.

Objective To investigate the effect of norcantharidin on growth inhibition and induction of apoptosis of human rectal cancer Colo 320 cells. Methods Norcantharidin (NCTD) in different concentrations were added to rectal cancer Colo 320 cells. Morphological characteristics of apoptosis were observed using the light microscope and transmission electron microscope. The expressions of Bag-1 and Bcl-2 proteins were tested by Western blotting. The growth inhibition of Colo 320 cells on the cell cycle was observed by flow cytometry. Results The apoptosis morphological changes of Colo 320 cells were observed by the light microscope and transmission electron microscopy. Flow cytometry analysis showed that the cell count of G2/M phase in experimental group was higher than that in control group ( <0.05) but the cell counts of G0/G1 and S phases have decreased in experimental group after treatment with NCTD at the concentrations of 5μg/mL, 10μg/mL and 20 μg/mL, and presented dosage dependence relations. The expressions of Bag-1 and Bcl-2 proteins have decreased. Conclusion Norcantharidin has inhibitory effect on rectal cancer Colo 320 cells, and the effect may be related to the cell cycle arrest and apoptosis.

Objective:To evaluate the diagnostic value of coronary angiography-based fractional flow reserve(caFFR)versus a wire-based fractional flow reserve(FFR)in elderly patients with stable ischemic heart disease.Methods:A total of 168 patients(186 vessels)who underwent a pressure wire(PW)-based FFR measurement from Jan.2015 to Dec.2019 in Beijing hospital were enrolled and analyzed retrospectively.Coronary angiography images and matched steady-state aortic pressure of patients were sent to the core laboratory for caFFR measurement under the blind method.All patients were divided into the non-elderly group(<65 years, n=93)and the elderly group(≥65 years, n=75). The diagnostic value of caFFR was evaluated by using the wire-based FFR cut-off value of ≤0.80 as the reference standard.The correlation and consistency of caFFR and wire-based FFR were analyzed, and compared between the non-elderly and elderly groups.Results:The caFFR had a good correlation and consistency with wire-based FFR in the elderly group( r=0.796, P<0.01). In non-aged versus elderly groups, diagnostic accuracy of caFFR was 91.9% versus 93.1%, diagnostic sensitivity of caFFR was 91.8% vs.93.2%, diagnostic specificity of caFFR was 92.3% vs.93.0%, all P>0.05.The area under the receiver-operating characteristic curve of caFFR had no significant difference between the non-elderly and elderly patients(0.964 vs.0.972, Z=0.00823, 95% CI: -0.037-0.052, P>0.05). Conclusions:The caFFR has a good diagnostic correlation and consistency with wire-based FFR in the elderly group, and caFFR's diagnostic performance in the elderly is similar to that in the non-elderly patients.

Objective To determine the audiological characteristics in 832 deaf children with biallelic causative mutations in GJB2 ,SLC26A4 gene .Methods The 832 patients received deafness gene screening ,553 were GJB2 gene biallelic causative mutations ,279 were SLC26A4 gene biallelic causative mutations .Patients were divided into four groups according to ages of hearing loss onset :<1 ,1~3 ,3~6 ,6~12 years old ,and the audiological character-istics and prevalence of GJB2 ,SLC26A4 gene mutations at different ages of onset .Results The prevalence of GJB2 gene mutations at four groups was 37 .97% (210/553) ,38 .34% (212/553) ,16 .27% (90/553) ,7 .41% (41/553) ,re-spectively ;the prevalence of SLC26A4 gene mutations at four groups was 25 .45% (71/279) ,44 .80% (125/279) , 20 .07% (56/279) ,9 .67% (27/279) ,respectively .The difference between GJB2 and SLC26A4 gene was significant(P=0 .001) .The prevalence of profound hearing loss with GJB2 gene mutations at four groups were 66 .67% (140/210) ,61 .32% (130/212) ,47 .78% (43/90) ,41 .46% (17/41) ,respectively .The difference was significant (P=0 .004) ,while the difference in 279 patients with SLC26A4 gene mutations was not statistically significant (P= 0 . 083) .Conclusion The age of hearing loss onset in patients with biallelic causative mutations in GJB 2 or SLC26A4 gene refers to 0~3 years -old ,hearing loss in patients with GJB2 ,SLC26A4 gene mutations gives priority to pro-found .The age of hearing loss onset is smaller ,the ratio of profound hearing loss is higher .Patients with severe and profound hearing impairment should be performed the genetic testing when the age of onset under 12 .

As a common emotional and psychogenic disorder, anxiety disorder seriously threats the human physical and mental health. Ventral tegmental area (VTA) is the canter of the mesocortical limbic circuit, with extensive bidirectional connections to forebrain areas, and plays important role in regulating reward, motivation, cognition, and disgust. Besides, VTA is involved in anxiety regulation by forming functional connections with multiple brain regions and connecting external stimulus information and feedback output behaviours. This article briefly summarizes the different cell subsets of VTA and its involvement in anxiety-related neural circuits.