After screening,the authors established a mouse model of pathomorphologically special,transplantable mammary spindle cell carcinoma SCC 891 in BALB/c mice.After 48 passages in 2.5 years,the growth of the tumor strain became stable with a 100% transplantibility.Its growth was quite active without observable spontaneous regression.The mean life span of the host mouse was 35.2?7.3 days.BALB/c mice of both sexes and of any age were susceptable to the carcinoma,and the carcinoma was sensitive to various anticancer drugs.

Objective To evaluate the curative effects and safty of contra-aperture dissection and skin bridge preservation in the treatment of low transphincteric perianal fistula.Methods Sixty subjects of low transphincteric perianal fistula were randomly divided into two groups.Thirty cases of treatment group were treated by contra-aperture dissection and skin bridge preservation,and 30 cases of control group were treated by anal fistulectomy.On the second,seventh and fourteenth day after operation,the postoperative pain,exudate and fever were recorded and scored.The curative time was observed.Anorectal dynamic changes were compared simultaneously to evaluate the curative effects and safety of contra-aperture dissection and skin bridge preservation.Results The scores of pain and exudate were significantly different between the treatment and the control group(P＜0.01).The wound-healing time was shorter in the treatment group than that in the control group((27.37±8.93) d vs.(32.73±9.45) d,P=0.000).There were significant differences in the anal resting pressure,anal maximal contraction pressure and active systolic pressure between the two groups (t =13.12,10.21,12.10;P＜0.01).There was no significant difference of total effect between the two groups(100％ and 93.3％;x2 =2.07,P＞0.05).Conclusion Contra-aperture dissection and skin bridge preservation can reduce postoperative pain,exudate and fever,shorten wound-healing time and protect anal functions in the treatment of low transphincteric perianal fistula.

Objective To reconfirm the mesangial cell differentiation potential of BMSCs and to study the mechanism of cell induction.Methods Rat BMSCs were isolated and incubated with platelet-derived growth factor(PDGF)-BB to induce the mesangial cell phenotype.At day 7,the cell morphology,mesangial cell-specific markers and cell contraction function were examined.MAPK/ERK kinase inhibitor(PD98059) was added to examine its impact on cell growth and mesangial cells marker expression.Results After cultivation under the differentiation condition for 7 days,the induced cells expressed ?-actin and Desmin,which highly resembled cultured mesangial cells in rat.The induced cells with increasing level of PDGF receptors mRNA expression changed into a wide range of shapes from spindle to stellate and were contracted in response to angiotensin Ⅱ.PD98059 perturbed the induced cells mesangial cell-specific markers mRNA expression.Conclusion BMSCs can differentiate into mesangial-like cells with PDGF-BB induction in vitro.The mechanism involved in the differentiation was mediated through MAPK/ERK1/2 signal transduction pathway.

AlM:To investigate the effect of teaching mode of problem- based learning ( PBL ) in the teaching of medical students' clinical ophthalmology.
METHODS: Five classes ( total 148 students ) were randomly selected as experimental group, using PBL method, at the same time another 5 classes ( total 151 students) were also randomly selected as control group, using lecture-based learning ( LBL) mode in 2010 grade. The scores of the experimental group were compared with control at the end of term. ln addition, students and teachers were respectively interviewed using self -administered questionnaire to obtain their evaluation for PBL practice.
RESULTS:The mean scores of PBL group (78. 35±7. 63) were significantly higher than control group (71. 68±6. 37) (P<0. 001). Most of students thought that their ability of referring, synthesizing and analyzing information was enhanced by PBL, and their skills both in written and oral were also improved. PBL made it easier to understand the contexts of course. lt was the best way to improve the effect of teaching in ophthalmology based on the increase of quality in novitiate that gives more chance to students of contacting with practice, developing the ability of clinical thinking and verifying the theory in clinical novitiate. Lots of teachers considered that the classroom atmosphere was more active, students were becoming more and more proactive on their classes and the relationship between students and teachers were more harmonious when PBL was used.
CONCLUSlON:Using PBL teaching mode can highly improve the teaching effectiveness of clinical epidemiology, which is worth popularizing.

Objective To study the relationship between tyrosine phosphorylation(TP)and protein expression of insulin receptor substrate-1(IRS-1)and insulin resistance in patients with gestational diabetes mellitus(GDM).Methods IRS-1 expression and TP in skeleton muscle tissue were determined by Western blot and immunoprecipitation in women with GDM(GDM group,n=22),normal pregnant women(normal pregnancy group,n=22)and normal nonpregnant women(normal nonpregnant group,n=13).Fasting plasma glucose(FPG)and fasting insulin(FINS)were measured by oxidase assay and immunoradioassay. Results(1)The levels of FPG,FINS,and insulin resistance index were calculated according to homeostasis model assessment [ HOMA-IR;(5.6?0.8)mmol/L,(15.4?5.1)mU/L,and 1.2?0.5 ] in GDM group were significantly higher than those in normal pregnancy group [(4.4+0.5)mmol/L,(10.6 ?3.1)mU/L,and 0.8?0.3;P

OBJECTIVE: To develop a reliable method to measure host cell protein(HCP)content of HEK293 cells in rAAV2-KAL vectors for clinic application. METHODS: The rAAV2-KAL vectors used for this study was purified by CsCl ultracentrifugation twice,then were subjected to by Western blot. The optimal linear range, minimum detection limit,and the accuracy and precision were verified by ELISA. Three batches of rAAV2-KAL were prepared by CsCl method. The change of HCP content during purification was determined to verify the method suitability and reliabilities. RESULTS: The optimal linear range of the method developed was 4-200 ng·mL-1, while the minimum detection limit of 4 ng·mL-1. The recovery rates of HEK293 cell protein at various concentrations were at range of 77.0%-115.0%,with a coefficient of variation of less than 20%. The HCP contents in three batches of rAAV2-KAL were less than 100 ng·mL-1, all data taken together indicated that HCP was effectively removed by CsCl ultracentrifugation. CONCLUSION: A reliable ELISA assay for residual host cell protein of HEK293 cells is successfully developed,which might be used for determination of HCP content in CsCl ultracentrifugation purified rAAV2-KAL for clinical application.

NSP4, as the diarrhea-related protein of rotavirus, is becoming an attractive candidate for vaccine development. To compare the immunogenicity of NSP4 from different genetic groups, we constructed eukaryotic expression plasmids comprising the NSP4 genes from four different genetic types using the pCI vector. The recombinant vectors were designated as pCI-97B6, pCI-97S36, pCI-97S34 and pCI-97SZ8, respectively. Following the conformation of the transient expression of the constructs in 293 cells, the plasmids were respectively subjected to the 5 round i. m. inoculation of BALB/c mice. The specific antibodies against NSP4 as well as the IgG1/IgG2a subclasses of immunoglobulin in mice sera were examined with indirect ELJSA after each immunization. The results showed that the immunization of plasmids expression NSP4s could elicit not only humoral but also cellular immunity, but the humoral immune response is dominant. There is a difference of immunogenecity among the NSP4 of different genetic type. Further studies were needed to focus on the relationship between the immunogenicity and protection effect.

Objective To investigate the status of rehabilitation demands of persons with speech disability in Beijing.Methods 355 persons with speech disability in Beijing in the Second National Sample Survey were involved in the study;their rehabilitation status and demands were evaluated.Results Persons with speech disability mainly needed rehabilitation in institute and in community and family,rehabilitation training and medicine service were needed mainly;persons with speech disability at different age and handicapped grade had different rehabilitation demands.Conclusion Rehabilitation awareness of persons with speech disability should be improved,a group of staffs on speech rehabilitation are base to satisfy rehabilitation training demands.

This article introduced the features and categories of emergency medicine.Combining the comprehension of teaching practices for many years,we considered that paying great attention to basic concepts is the primary problem in emergency medicine teaching.

Background The select of supporter is critical for the construction of tissue engineering cornea.Many carrier carl be utilized in the construction of tissue engineering cornea,but de-cellular corneal matrix is known to be one of optimal supporters.Objective Present study was to investigate the characteristics of de-cellular corneal matrix of porcine of structure and biocompatibility for rabbit cornea stroma and limbal epithelial ceHs. Methods The porcine cornea was prepared as de-cellular corneal matrix of porcine by the application of detergent enzyme combined process.The corneal epithelial cells,keratocyte and endothelial cells of porcine were removed completely and stored in -20℃ refrigerator after sterilization.The morphology of de-cellular corneal matrix of porcine was examined by hematoxylin-eosin staining under the light microscope.The structure characteristics of de.cellular corneal matrix of porcine under the scan electron microscope,and its physics features were investigated by the evaluation of water content,strength,expansion and transparency.The de-cellular corneal matrix of porcine were implanted to cornea stroma of rabbit and co-cultured with rabbit corneal epithelial cells for 4 weeks in vitro to assess the keracyte compatibility. Results The epithelial cells,keratocyte and endothelial cells of porcine were removed completely by trypsogen digestion.The collagen fibril network and collagen plates paralleled to corneal surface under the light microscope.The water content,strength,expansion。Ratio of light transparency of de-cellular corneal matrix of porcine were similar to normal porcine cornea.After implantation of de.cellular comeal matrix of porcine into rabbits corneal stroma,the edema of tissue was found in one week,and edema disappeared on two weeks and became clear on four weeks after surgery.The de-cellular eorneal matrix attached to rabbit cornea stroma well.No inflammatory eell and new vessel were found after surgery.The co-cultured rabbit corneal epithelial cells differentiated and proliferated on the surfaee of de-cellular corneal matrix and showed positive response for CK3.No statistically significant differences were found in the water content,strength,expansion of de-cellular cornea matrix of porcine among the normal,before dehydration,2 and 4 hours after dehydration cornea matrix(P＞0.05).However,the transparency was much better in the corneal matrix with 2-hour,4-hour dehydration in comparison with non-dehydration one(P＜0.05). Conclusion The structure features of de-cellular cornea matrix of porcine are similar to normal porcine cornea.Good biocompatibility is proved for xenogenesis of rabbit cornea.