1.Strengthening the project management and improving the quality of continuing medical education
Chinese Journal of Medical Education Research 2002;0(01):-
This report is an overview of continuing medical education project launched and managed by Office of Continuing Education,Peking University Health Science Center.It summarized the procedure management of the continuing medical education project,the design of Internet-based continuing education information management systems,project supervision,attention to the implemen-tation of attendance system,strict issue of credit certificates,and other measures.Finally,some thoughts on continuing medical education project management were proposed to be discussed with peers.
2.Assessment of fetal lung volumes using three-dimensional ultrasonography
Chinese Journal of Ultrasonography 2009;18(11):963-965
Objective To build a nomogram of normal fetal lung volumes (left,right and total)throughout gestational age estimated by 3-dimensional ultrasonography.Methods Left and right lung volumes were assessed in 324 normal and singleton fetuses of gestational age 16-37 weeks by 3-dimensional ultrasonography using the technique of virtual organ computer-aided analysis(VOCAL) at a rotational step of 30 degrees.The relationships between left,right,and total lung volumes,and gestational age were assessed by correlation and regression analysis.Results The right,left,and total lung volumes were highly correlated with gestational age (P<0.001),and the correlation coefficient was 0.966,0.973 and 0.990respectively.The best-fit exponential curve regression equations of left lung volume was:y=0.207exp~(0.143X);right lung volume was:y=0.301 exp~(0.14X);total lung volume was:y=0.508 exp~(0.142X).Conclusions A nomogram of fetal lung volumes estimated by 3-dimensional ultrasonography from 16 to 37weeks gestation is described,and reference values may be useful for the prenatal prediction of pulmonary hypoplasia.
4.Therapeutic effect and mechanism of neuregulin on cerebral ischemia reperfusion injury in mice
Hongting MA ; Tao WANG ; Zhen LI
Chinese Journal of Pathophysiology 2009;25(3):460-466
AIM: To study the effects of neuregulin-1β (NRG-1β) on the nervous behavioral function, cerebral infarction volume, brain water content (BWC), neuroal apoptosis and aquaporin-4 (AQP-4) expression in astrocytes after cerebral ischemic reperfusion in mice. METHODS: Intraluminal thread methods were applied to establish the middle cerebral artery occlusion reperfusion (MCAO/R) model in mice. Neuregulin-1β (2 μg/kg) was injected into the internal carotid artery for treatment. The nervous behavioral function was evaluated by Bedersons test. The cerebral infarction volume was observed with tetrazolium chloride (TTC) staining. The BWC was measured by calculating the dry-wet weight ratio. The apoptotic positive cells were counted by immunofluorescence assay. The expression of AQP-4 was determined by immunohistochemical method. RESULTS: Nervous behavioral malfunction appeared in all the mice with left middle cerebral artery occlusion (MCAO) and/or reperfusion. The infarction focus showed in the ischemic hemisphere following the injury. The BWC, the numbers of neuroal apoptotic cells and AQP-4 expression in astrocytes were higher than those in sham control group. In MCAO/R+NRG-1β treatment group, the nervous behavioral function at ischemia 24 h significantly improved, the numbers of apoptotic positive cells reduced and the infarction volume decreased significantly than those in MCAO/R group (P<0.05). The BWC and AQP-4 expression in astrocytes showed no significant difference compared with MCAO/R group (P>0.05). In the reperfusion 22 h, 46 h and 70 h groups, the five indexes mentioned above were significantly different from those in the corresponding MCAO/R groups (P<0.05). CONCLUSION: NRG-1β might reduce cerebral edema and infarction volume, and improve the nervous behavioral function via down-regulating the expression of AQP-4 in astrocytes and inhibiting the neuronal apoptosis induced by ischemia reperfusion injury.
5.Study on the Nutrition Requirements of American Ginseng Ⅵ. Study on Nitrate Reductase Activity (NRA)of American Ginseng (Panax quinquefolius)
Xiaojun MA ; Zhen CHEN ; Yangjing ZHAO
Chinese Traditional and Herbal Drugs 1994;0(07):-
Two peaks were present in the NRA annual curve of Panax quinquefolius. A high peak appeared in late April and a smaller peak occured in early July. It is important to apply N2 fertilizers just before the appearance of the two peaks. Experiment on the effect of different light and pH showed that higher NRA were formed at 4000 Lx and pH 4.3~6.0.
7.The use of Apofix interlaminar clamp for the treatment of atlantoaxial instability
Lequn MA ; Wanxin ZHEN ; Liang XU
Chinese Journal of Orthopaedics 1996;0(10):-
Objective To discuss the application of Apofix interlaminar clamp for the treatment of atlantoaxial instability. Methods From April 2000 to July 2004, 30 patients with atlantoaxial instability were treated with posterior atlantoaxial fusion and Apofix fixation. There were 24 males and 6 females. The mean age of the patients was 41 years (range, 19 to 67 years). The patients included 5 with atlantoaxial dislocation, 25 with odontoid fracture (including fresh fracture for 21, old fracture and nonunion for 4; Anderson Ⅱ for 23 and Anderson Ⅲ for 2). After reducted by skull traction, atlanto-occipital space, arcus posterior atlantis and axial laminar were exposed during operation, upper and lower hooks were inserted. The iliac bone graft was inserted into the space of C1 and C2, the connecting rod of the clamp was compressed and fixed. Results The follow-up of all cases ranged from 8 months to 3 years and 10 months (with the mean of 27 months). There were 28 cases with complete reduction of fracture and dislocation, 2 cases in incomplete reduction. The operation time was 70 to 150 minutes, and the average blood loss was 65 ml. Patients could sit up 3 days (2 to 6 days) after surgery with soft collar. The mean off-bed time was 7 days (2 to 10 days) after operation in the patients without or less spinal cord injury. All cases obtained solid bony fusion 3 months postoperatively. No severe complications such as injuries of vertebral artery, nerve root and spinal cord or aggravation of spinal cord injury occurred. Conclusion Apofix interlaminar clamp has advantages of convenience in operation, provided reliable and safe stability for atlatoaxial segment. The results suggested that this technique is an efficient, reliable segmental posterior fixation.
8.STUDIES OF HEMATOPOIETIC STEM CELLS Ⅰ. OBSERVATIONS ON THE PROPERTY AND FUNCTION OF MOUSE PLURIPOTENTIAL STEM CELLS
Shengyuan WANG ; Zhen LI ; Yixing MA
Acta Anatomica Sinica 1953;0(01):-
The properties and functions of mouse pluripotential stem cells (CFU-S) were studied with spleen colony technique and other related methods. The data expressed that there is a linear relationship between the number of transplanted marrow cells and the number of spleen colonies that developed. Among various hematopoietic tissues, bone marrow is the richest source of CFU-S. Spleen and peripheral blood also contain a few of such cells. The percentages of CFU-S in these organs are 0.7%, 0.05% and 0.01% in sequence. No CFU-S can be found in thymus or lymph nodes. Under normal conditions, most of the CFU-S are in G_o phase with a small proportion (6.7%) in S phase.Self-renewing capacity, an important hematopoietic function of CFU-S, was measured by the experiments of single spleen colony retransplantation. The value of the probability of self-renewal, p, is calculated as 0.76. CFU-S has an active ability of migration. It was found that a number of CFU-S either from the marrow cell suspension injected intraperitoneally or from an entire encapsulated spleen which was placed free in the peritoneal cavity after ligation of its blood vessels can penetrate through a lot of barriers to develop spleen colonies in the lethally irradiated mice. A dose of 500~700 rad ?-irradiation apparently stimulates the CFU-S migrating from bone marrow to circulation.
9.Quantification of vascularization within spherical porous ?-TCP scaffold in vivo
Chao MA ; Zhen WANG ; Jianxi LU
Orthopedic Journal of China 2006;0(10):-
[Objective]To explore the vascularization within spherical porous ?-TCP scaffolds in vivo.[Method]Thirty adult rabbits were selected and divided into 5 groups randomly.Spherical porous ?-TCP scaffolds(the diameter was 2 cm,the pore size was 500~600?m,the interconnection size was 110~120 ?m) were harvested at 1,2,4,8 and 12 weeks after embedded into muscle-fascia lumbodorsalis pouches in each rabbit separately,in order to observe the vascularization by means of morphological and quantificational analysis.[Result]No vessel was detected at one week after surgery,and only a few immature vascular buds could be seen at the 2nd week.The first vascularization peak could be observed at 4 weeks,characterized by the growth of quantity of new blood vessels(P0.05).[Conclusion]The process of vascularization comprises two phases,the quantity increasing in the early stage and the quality enhancing in the later stage.The special architecture and biodegradation characters of scaffolds could influence the vascularization.
10.Production and Regulation of Platelet Derived Growth Factor in Keratinocytes and Dermal Fibroblasts
Jiangzhong ZHANG ; Xueyi ZHEN ; Shengqing MA
Chinese Journal of Dermatology 1995;0(04):-
Objective To evaluate the production and regulation of platelet derived growth factor (PDGF) in the skin. Methods Normal human keratinocytes (NHKs) and human dermal fibroblasts (HDFs) were cultured, PDGF peptides were measured by ELISA and PDGF B chain mRNA was detected by Northern hybridization. Results The results showed that NHKs constitutively produced PDGF molecules, phorbol 12 myristate 13 acetate (PMA) inhibited PDGF production, while 1, 25 dihydroxyvitamin D 3 enhanced its production. TNF alpha, interferon ? and interleukin 1 alpha all failed to affect PDGF production. On the other hand, HDFs produced no PDGF molecule in spite of a low level of PDGF B chain mRNA expression in Northern hybridization, suggestting a post transcriptional blocking of PDGF production in HDFs. Conclusion The results obtained above indicate that epidermal keratinocytes may be the major PDGF generating cells, whereas dermal fibroblasts the PDGF responsive cells in the skin.