We used epidemiological method to analyse vegetable salmonella carrier rates in six differ- ent vegetables at 12 vegetable markets in two urban districts of Kunming city from March to May 1992. Results showed the total vegetable salmonella carrier rate was 22.71%. showed no significant difference. The carrying rate of cordate houtlugnia is the highest in the six kinds of vegetables. There was a rising tendency of salmonella carrier rate in vegetables from March to May. Two hundred and seventy salmonella strains were isolated, which belonged to six groups of A, B, C, D, E, F, and 14 serum types. Among them, paramount S. Paratyhi-A bacterium took predominance and accounted for 48.89%, the next were S. tyhi and S. Paratyhi-B.

The rapid development of human micro-ecology (human microbiome) in recent years has opened up new medical prospects for revealing the close relationship between microorganism and human health and disease.As the second genome of human,the special relationship between the microorganism and the host and its important function have brought new ethical and social problems,which requires to rethink and reform the existing ethical norms.This paper focused on the seven perspectives of “identity”,ownership,informed consent,risk benefit assessment,privacy,commercialization and public health,and demonstrated the importance to construct the ethics of micro-ecological research,which would enrich and expand the connotation of bioethics in theory and better guarantee the benign development of micro-ecology research in practice.

In this experiment, the crude Fructus Crataegi, its baked product, the products baked to dark brown and baked to charcoal were compared regarding the gastrointestinal promote function of rat, the content of free acids in stomach, total acids, pepsin and nitrite as indices. As a result, the crude and the fried product possessed greater effects on the digestive ability of rats, but their nitrite content was lower. It was preliminary suggested that adding the crude and the fried product into digestant be an optimum selection

BACKGROUND: Wnt signaling pathway is a key regulator of cellular proliferation and differentiation, but its correlation with neural differentiation of bone marrow mesenchymal stem cells (BMSCs) is not very clear. OBJECTIVE: To find out the molecules of the Wnt family which are involved in differentiation of rat BMSCs into neuron-like cells. METHODS: The rat BMSCs were separated and cultured in vitro. The morphology of the BMSCs was observed. Flow cytometry analysis was performed to detect cell phenotype CD44, CD9, CD34 and CD45. Wnt3a and Wnt5a were respectively combined with basic fibroblast growth factor to induce BMSCs differentiation into neuron-like cells, and then were identified by using immunocytochemistry and RT-PCR. RESULTS AND CONCLUSION: The BMSCs were long-spindle. CD9 and CD44 were highly expressed, while CD34 and CD45 were lowly expressed. Nestin and neuron specific enolase were positive but glial fibrillary acidic protein were not obviously expressed when they were cultured with Wnt3a. In Wnt5a group, Nestin expression was weakly positive, while neuron specific enolase and glial fibrillary acidic protein were negative. RT-PCR result revealed Nestin expressed both before and after induction in the Wnt3a induced group, neuron-specific enolase exhibited apparent amplified bands 5 days after the induction, and more apparent at 10 days. A weak amplification band of glial fibrillary acidic protein could be seen at 10 days after the induction. In Wnt5a and control groups, BMSCs induced by 10 days weakly expressed Nestin, while neuron-specific enolase and glial fibrillary acidic protein were almost not expressed. It is indicated that Wnt3a molecule can promote the differentiation of BMSCs cultured in vitro to neuron-like cells.

BACKGROUND:At present, there are no studies of comparing the effect of silk fibroins from different sources in repair of osteochondral defects. OBJECTIVE:To compare the effect of mulberry silk- and tussah-derived silk fibroin scaffold materials in repair of osteochondral defect. METHODS:Totaly 20 New Zealand white rabbits were obtained to prepare osteochondral defect models on the unilateral knee joint and randomly divided into five groups: control group, experimental group 1, experimental group 2, experimental group 3 and experimental group 4. Rabbits in the control group were not implanted any materials. In the experimental group 1, 3 layers of mulberry silk protein scaffolds stuck together to fil in defects. In the experimental group 2, one mulberry silk protein scaffold coated with transforming growth factor-β3 was stuck with two mulberry silk protein scaffolds coated with bone morphogenetic protein-2 to fil in defects. In the experimental group 3, three layers of tussah protein scaffolds stuck together to fil in defects. In the experimental group 4, one tussah protein scaffold coated with transforming growth factor-β3 stuck together with two tussah protein scaffolds coated with bone morphogenetic protein-2 to fil in defects. At 8 weeks post surgery, articular cartilage repair area was observed histopathologicaly. Type I and II colagen expressions were determined. RESULTS AND CONCLUSION:The colagen fibers in experimental group 1 were widely distributed in the ful-thickness defect area. The colagen fibers in the experimental group 2 were paralely distributed on the surface of repair area, verticaly distributed from the middle and bottom to the top direction. Colagen was observed on the surface of repair area in the experimental group 3. The cartilage-like cels presented clumped distribution on the surface and at the bottom of scaffold. The type I colagen expression in the repair area was strongly positive in these four experimental groups. The type II colagen expression in the repair area of experimental 1 and experimental 2 groups was weak. The type II colagen expression in the repair area of experimental 3 and experimental 4 groups was strongly positive. These results demonstrate that these two kinds of silk fibroins can both repair osteochondral defects, in which mulberry silk proteins tend to form bone tissue, and tussah silk proteins tend to form cartilage tissue.

BACKGROUND: Concentrated growth factor (CGF) fibrin membrane is involved in metabolism regulation, which has been applied in bone remodeling. Previous Studies have found that the cytoplasts of osteoblasts, interstitial cells and osteocytes in distraction osteogenesis are positive for osteoprotegerin and receptor activator nuclear factor kappa B ligand (RANKL).OBJECTIVE: To explore the mechanism of bone orthopedic effect and the promotion effect of CGF fibrin membrane on the distraction osteogenesis of the rabbit mandible.METHODS: Twenty-four white rabbits were randomly selected. Distraction osteogenesis was performed unilaterally in the rabbit left mandible (control group); CGF fibrin membrane was fixed on the inner surface of distractor, and the distraction gap was then completely wrapped prior to distraction osteogenesis in the right mandible (experimental group).At 1, 7, 14 and 28 days of consolidation period, the rabbits were sacrificed and the bilateral mandibles were taken for hematoxylin-eosin staining, western blot assay and immunohistochemical staining to detect the expression of RANKL and osteoprotegerin in the newborn bones; the osteogenesis in the distraction gap was observed and compared between two groups.RESULTS AND CONCLUSION: The osteoprotegerin positive cells and positive area percentage in the experimental group were significantly higher than those in the control group at 1, 7 and 14 days after distraction osteogenesis (P < 0.01). The RANKL positive rate and positive area percentage in the experimental group were significantly higher than those in the control group at 1 and 14 days after distraction osteogenesis (P < 0.05 or P < 0.01). Western blot assay showed a higher ratio of RANKL/osteoprotegerin in the control group than the experimental group (P < 0.01). Our findings indicate that CGF fibrin membrane can promote osteogenesis and mineralization in the distraction gap of the rabbit mandible, which is beneficial for distraction osteogenesis in the mandible.

BACKGROUND: Mesenchymal stem cells (MSCs) are capable of differentiating into a variety of lineages, including bone, cartilage, or fat, depending on the inducing stimuli, specific growth and differentiation factors.Recombinant human bone morphogenetic protein 2 (rhBMP-2) produced by gene engineering has an obvious osteoinductive activity and can induce undifferentiated mesenchymal cells into cartilage and bone irreversibly, resulting in new bone formation. Basic fibroblast growth factor (bFGF) modulates chondrogenic and osteogenic differentiation of MSCs.OBJECTIVE: To investigate the effect of bFGF and rhBMP-2 on the differentiation and proliferation of cultured rabbit mesenchymal stem cell in order to find out an optimal way of osteogenesis instead of conventional osteogenic supplements (OS).DESIGN: A randomized and controlled trial.SETTING: General Institute of Orthopaedic Oncology, Tangdu Hospital,Fourth Military Medical University of Chinese PLA.MATERIALS: The subjects were rabbit mesenchymal stem cells cultured by the author.METHODS: This experiment was conducted at the Center of Orthopaedic Surgery, General Institute of Orthopaedic Oncology, Tangdu Hospital,Fourth Military Medical University of Chinese PLA from June 2004 to December 2004. ①Rabbit MSCs cultured in vitro were treated with different growth factor (100 μg/L rhBMP-2, 100 μg/L bFGF, 10 μg/L rhBMP-2and 100 μg/L bFGF and OS; ②The proliferation and differentiation of MSCs were observed through activity of MTT, expression of alkaline phosphatase(ALP), and von Kossa staining.MAIN OUTCOME MEASURES: the rate of proliferation and the activity of ALP.RESULTS: ①rhBMP-2 could promote the proliferation and differentiation of MSCs, especially the cell differentiation; ②bFGF could stimulate the proliferation , the cellular proliferation rate increased 100% as compared with control group, and has no effect on differentiation of MSCs , but it could enhance effect on the cell proliferation of rhBMP-2.CONCLUSION: bFGF and rhBMP-2 are effective induction factors for MSCs. Both of them can stimulate the proliferation and differentiation of MSCs in vitro. bFGF and rhBMP-2 exerted a synergetic action in speeding up the pace of osteoinduction and osteogenesis and can be used to differentiate seed cells for tissue engineering bone.

Objective To compare and evaluate the defect-repaired capabilities of human bone morphogenetic protein-2(hBMP-2) gene modified tissue engineered bone in the segmental bone defect model of rabbit's radius.Methods Rabbit's bone mesenchymal stem cells (BMSCs)were transferred with hBMP-2 gene through Adeno-XTM adenoviral expression systems,then seeded onto the compound scaffold of calcium phosphate cemept(CPC)and fibrin glue(FG)to construct a new kind of gene modified tissue engineered bone after proliferation in vitro for three weeks(Group A).Meanwhile,the compound scaffold of calcium phosphate cement(CPC)and fibrin glue(FG),which were seeded by rabbit's bone knesenchyrmal stem cells(BMSCs) after proliferation in vitro for three weeks(group B)and the compound scaffold without cells(Group C)acted as control groups.Then,three kinds of reconstructive modalities were implanted into segmental bone defect of donator rabbit's radius.Besides these three groups,bone defect model of rabbit's radius without treatment(Group D)represented blank group.The defect-repaired capabilities were assessed by gross observation,radiograph,Single Photo Emission Computed Topography (SPECT)and histological analysis in the 4th week,8th week and 12th week after operation.The rates of bone healing in the different groups were compared each other.Results All defects that had been treated with implants(Group A,B,C)exhibited new bone formation and could attain osseous tissue healing 12 weeks after operation,but defects in blank group(Group D)were repaired only by fibrous tissue.The defects in the Group A regenerated more new bone,bridged earlier and stronger than those in the Group B and Group C.The quantity and rate of new bone formation in the Group B and Group C had no significant difference and the rates of bone healing in different groups showed the same results.Conclusion hBMP-2 gene modified tissue engineerod bone have better potential to form new bone and the rate of bone healing in repairing bone defects is higher,so this way is an optimal kind of material for artificial bone graft.

A medical metrology supervision system is proposed.It analyses the composition structure including data input and print,statistic inquiry,data acception and report as well as data file management.The technological characteristics are analyzed including system classification,authorization and password control,system safety and file output.Making the military medical metrology supervision more standardized and scientific,the system remarkably improves the work efficiency.

Objective To study the spare demand rate and storage quantity probability model for military medical equipment in order to make a valuable reference to the decision-making of medical organization for the further medical support.Methods The reliability and maintainability of spare in the process of equipment maintenance were studied,and the signifi-cant factors which have influence on spare demand rate were analyzed.By using Passion theory,spare demand rate proba-bility model of medical equipment was deduced,especially for repairable components and un-repairable components spare.By calculating the probability of replaceable spare,a useful method to scientifically make out the storage quantity of mili-tary medical equipment was provided.Results The models of spare demand rate and storage quantity were made for mili-tary medical equipment maintenance.Conclusion The solution of the model is simple and convenient and the calculating results shows that the spare demand rate and storage quantity is close to the reality.It can meet the requirements of pre-diction of spare demand rate and determination of the storage quantity in maintenance support of medical equipment in peacetime.