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Objective To investigate the status of microbial contamination in domestic washing machines,and pro-vide basis for strengthening hygiene and health management.Methods On-the-spot sampling,laboratory microbial detection,and questionnaire survey were performed to investigate and analyze the hygiene treatment and microbial contamination of domestic washing machines of Beijing residents.Results Source water of 115 washing machines were collected,no bacteria were detected.The total number of bacteria and fungi in washing water from 115 washing machines was 0-135 000 CFU/mL (13 206 CFU/mL on average)and 0-690 CFU/mL (229 CFU/mL on average) respectively.There was significant difference in bacterial colony forming unit in washing water from washing ma-chines of different length of service (P <0.05).15 specimens of washing water from 15 washing machines were per-formed bacteriological detection,17 kinds of bacteria were detected,most of which were opportunistic pathogenic bacteria.The major detected bacteria was Pseudomonas aeruginosa (66.67%),followed by Staphylococcus aureus (60.00%)and Escherichia coli (53.33%).Survey showed that 32.17% of residents reflected the washing ma-chines had peculiar smell and mildew spots,48.69% of users chose to open the covers for ventilation,38.26%adopted local wiping and cleaning of filter bags,only 10.43% chose to soak with disinfectant,while 24.35% didn’t know how to deal with.Conclusion Microbial contamination of domestic washing machines is serious,improper use and maintenance of washing machine is not conducive to health.
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Objective To explore mechanics condition in artificial knee joint replacement tibial prosthesis with different shaft body shapes implanted into tibia in different inclination angle,and discuss which shaft shape in tibial prosthesis is suitable in different inserted angle.Methods Finite element model of tib-ial prosthesis with cylindrical handle,square taper shank,columns taper shank,ladder airfoil cross wing shape with column wing handle were built and assembled with bone cement and polymer polyethylene pad.The finite element software ANSYS15.0 was used to analyze the variation of stress and strain of all kinds of body shape handle prosthesis in tilting to 0° and 3°,6°under the working condition of the existing literature data.Results Different stress and strain changes were observed in the finite element models of tibial prosthesis with different shaft shapes in tilting to 0°,3°,and 6°.Conclusions For the different tibial prostheses of 6 kinds of shaft shapes,when placed in tilting to 3°,prosthesis with cylindrical taper shank and column wing were suitable to be chosen; and when placed at 0°,prosthesis with ladder airfoil handle should be avoided to use,because of stress concentration easily could lead to a fractured in bone cement; Placed in the lean 6° level,prosthesis with cylindrical,square taper shank,cylindrical handle taper shank and column wing handle were suitable to be chosen.
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BACKGROUND: Tension band suture fixation is always used in treating patellar fracture, and its modified method of Kirschner wire plus tension band steel-wire is also widely applied. But because the traditional surgery always causes massive incision and scar formation, it affects the appearance and function of knee joint.OBJECTIVE: To investigate the clinical curative effect of percutaneous puncture plus tension zone steel-wire fixation for the treatment of patella closed transverse fracture.DESIGN: Retrospective analysis:SETTING: Second Hospital of Medical College, Xi'an Jiaotong University.PARTICIPANTS: Twenty-nine patients with closed patellar transverse fracture admitted by Department of Orthopedics,Medical College of Xi'an Jiaotong University were selected from an average age of 36 years old. Only people that were diagnosed by X-ray as closed patellar transverse fracture were enrolled, and the informed consent was obtained from them.jostled until resetting, and then the fractured pieces were clamped by a clavical clamp to fix. Two incisions were made at the upper and lower ends of patella, and two were penetrated from the incision until its tip out of the lower hole of the same Kirschner wire under skin. The soft steel wire was drawn tightly and bended along the tip of Kirschner wire. The three-grading method, and the recovery of patients in 4 years after operation was evaluated according to the composite evaluation means about the knee joint established by Xu et al (pain, movement range of knee joint and reset of the fracture in patellar face. Meanwhile, the postoperative complications were observed.MAIN OUTCOME MEASURES: Wound healing, postoperative functional recovery and complications of patients.cases scored in grade 1, accounted for 93%, 2 cases in grade 2, accounted for 7%, who were recovered after change of means about the knee joint established by Xu, 26 cases were excellent, and 3 were good; in the movement range of knee joint, 27 cases were excellent and 2 were good; in the resetting of fracture, 26 cases were excellent and 3 were infection, traumatic arthritis, or other complications were found in patients.CONCLUSION: Percutaneous internal fixation with Kirchner needles combined with tension band wires for treatment of closed patella transverse fractures is featured by minimal trauma, fast recovery and beautiful outlook in the operative area. Moreover, it permits early movement in the knee joints. This method has a satisfied clinical curative effect.
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BACKGROUND:Previous animal studies have revealed that osteogenic growth peptide (OGP) applied locally or systemically could promote fracture healing. But the disadvantages of short in vivo half-life and low oral bioavailability limit its clinical application.OBJECTIVE: To study the encapsulation and delivery of synthetic OGP (sOGP) from biodegradable polymeric microspheres in vitro so as to choose better carrier for the future study.DESIGN: Grouping observation and comparative trail.SETTING: Laboratory of School of Life Science and Technology, Xi'an Jiaotong University.MATERIALS: sOGP was synthesized by Xi'an Langene Bio-science Co., Ltd. with Fmoc system. The purity of sOGP after purification was over 98 % identified by reverse phase high performance liquid chromatography, and the molecular weight of sOGP was 1 523 650, which was consistent with the theoretical value (Mr 1 523 750); the result of whole sequence analysis of sOGP was consistent with the theoretical sequence of OGP. Poly (lactic-co-glycolic acid) (PLGA,50:50, Mr 30 000; 75:25 Mr 80 000) was obtained from Shandong Medical Instrumental Institute (Ji'nan, China)METHODS: PLGA with a 50:50 or 75:25 lactide to glycolide ratio was used for microsphere preparation using a modified double emulsion solvent extraction Water-in-oil-in-water (w/o/w) technique. The surface structure and appearance of microsphere was observed under scanning electron microscope; particle size distribution of microsphere was counted by laser diffraction particle sizer; efficiency of encapsulation, release time and the structural integrity of sOGP released from PLGA were assessed using high performance liquid chromatography (HPLC).RESULTS: ①Spherical microspheres of sOG-PLGA were formulated successfully. The average particle diameter of the PLGA 50:50 microsphere was (19.6±4.5) μm, efficiency of encapsulation (83.9±4.2)% with (83.9±4.2) % drug-loading efficiency, while the PLGA 75:25 microspheres showed an average size of (35.8±3.6) μm, efficiency of encapsulation (65.6±6.8)% with (65.6±6.8)% drug-loading efficiency. ②HPLC results indicated that sOGP were not chemically altered,physically aggregated but presented a intact structure as the original sOGP. An initial burst release was observed for both PLGA microspheres, especially from PLGA 75:25. sOGP was released from PLGA 50:50 microsphere for 56 days,and from PLGA 75:25 microspheres for over 70 days. The cumulative release of sOGP from PLGA 50:50 for 35 days was significantly lower than from PLGA 75:25 (P ＜ 0.05).CONCLUSION: The controlled release of sOGP encapsulated within PLGA 50:50 is better than the delivery from PLGA 75:25. Moreover, the release time could meet the requirements for fracture or bone defect site.