BACKGROUND:Three-dimensional printing technique has been applied in medical fields since it was invented in the end of 20th century. Recently it has been widely used in manufacturing scaffolds for bone tissue engineering. OBJECTIVE:To review the basic concept of the scaffold for bone tissue engineering, the basic requirements for three-dimensional printing technique in scaffold engineering, different materials used in bone tissue engineering, the advantages and limitations of three-dimensional printing technique and the outlook of three-dimensional printing technique applied in manufacturing scaffold for bone tissue engineering. METHODS: The first author did a computer-aided retrieval of the MEDLINE database, Science Direct database, CNKI database, and CQVIP database for articles relevant to three-dimensional printing technique used in manufacturing scaffolds for bone tissue engineering published between January 1990 and February 2015. The key words were three-dimensional printing, tissue engineering, rapid prototyping technology, scaffold, materials in English and Chinese, respectively. Repetitive studies were excluded, and 33 of 52 related literatures were adopted in result analysis. RESULTS AND CONCLUSION: Three-dimensional printing technique has many advantages such as high resolution, high velocity and the freedom to build unlimited geometries. There are some requirements for the powder and binder used to construct bone tissue engineering scaffolds using the three-dimensional printing technique, such as the flowability, stability and wettability. A wide range of materials can be used: synthetic and natural polymers, ceramics, as wel as composites of the aforementioned. Various kinds of powder take responsibility of different features of scaffolds, resulting from the advantages and disadvantages of different materials. Although this technique has some limitations such as high cost and the difficulty of commercial production, its application stil has a bright future.

AIM: To observe the efficacy of high concentrations of sodium hyaluronate ( 3g/L SH ) for moderate to severe dry eye.
METHODS: Forty moderate to severe dry eye patients were included in the study according to the diagnosis criteria and randomized into two groups. The patients of the trial group received topical administration of high concentration sodium hyaluronate (3g/L), and those of the control group received sodium hyaluronate ( 1g/L ) plus recombinant human epidermal growth factor. The dry eye symptom scores, ocular surface disease index ( OSDI) scores, tear film break-up time ( BUT) , SchirmerⅠ test and corneal fluorescein staining score were evaluated. All the indexes were compared between the two groups 2wk before and after treatment.
RESULTS: There were no significant differences of the indicators between the two groups before treatment. After 2wk treatment, the differences were statistically significant compared to former except for the SchirmerⅠtest. Compared with the control group, the symptom scores and the OSDI scores were lowered. No significant differences were found in the other indicators between these two groups.
CONCLUSION: Topical usage of highconcentrations of sodium hyaluronate (3g/L) is beneficial for remitting the ocular symptoms in moderate to severe dry eyes, and also improve the quality of life of patients.

Objective To evaluate the efficacy of different doses of dezocine for decreasing the minimum alveolar concentration (MAC) of desflurane.Methods ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 50-70 yr,undergoing elective lower abdominal surgery performed under general anesthesia,were divided into 4 groups:control group (group C)and different doses of dezocine groups (D1,D2 and D3 groups).Before induction of anesthesia,in D1,D2 and D3 groups,dezocine 0.050,0.075 and 0.100 mg/kg were intravenously infused,respectively,while in group C,the equal volume of normal saline was given instead of dezocine.The adverse reactions were observed.Propofol 3 mg/kg was given for induction of anesthesia 15 min later until patient' s consciousness and spontaneous respiration disappeared.Laryngeal mask airway was inserted and the patients were mechanically ventilated.Up-and-down sequential allocation was used to determine the MAC of desflurane during maintenance of anesthesia.The end-tidal concentration of desflurane was set at 8.0％ and maintained at this level for at least 5 min before skin incision in the first patient.Each time the concentration of desflurane increased/decreased in the next patient depending on whether or not the body movement developed.The ratio between the two successive concentrations was 0.9.The point between the positive response and negative response served as a cross-over point.After at least 7 independent cross-over points were observed in each group,the experiment was stopped.The MAC and 95 ％ confidence interval of desflurane were calculated.Results No adverse reactions developed in each group.The MAC of desflurane was significantly lower in D1-3 groups than in group C,in groups D2.3 than in group D1,and in group D3 than in group D2.Conclusion Dezocine 0.100 mg/kg injected intravenously at 15 min before induction of anesthesia provides a better efficacy for decreasing the MAC of desflurane in the patients.

Debates over PBL have never stopped since its introduction to medical education in 1969 and are even becoming more heated.This paper expounds on the origin and definition of PBL,and then describes and analyzes the application of the clinical teaching in orthopedic surgery.

Objective To evatluate the effect of dexmedetomidine on intraoperative wake-up test during cerebral functional area operation performed under combined iv propofol-remifentanil anesthesia.Methods Twenty-seven ASA Ⅰ or Ⅱ patients (both sexes) aged 17-43 yr with a body mass index of 20-24 kg/m2 undergoing op-eration on cerebral functional area during which intraoperative wake-up test was performed were randomly divided into control group (group C,n =13) and dexmedetomidine group (group D,n =14).Anesthesia was induced with midazolam,sufentanil,etomidate and rocuronium and maintained with TCl of propofol (Cp =3-5 μg/ml) and remifentanil (Ce =2-6 ng/ml).BIS value was maintained at 55-65.In group D after dura of brain was opened,a loading dose of dexmedetomidine 0.3 μg/kg was administered iv over 15 min followed by continuous iv infusion at 0.2 μg· kg-1 · h-1 while TCI of propofol and remifentanil were suspended.In group C after opening of dura,Cp of propofol TCI was reduced to 0.5 μg/ml and Ce of remifentanil to 0.5 ng/ml.The wake-up time and development of hypertension,tachycardia,headache,dysphoria,delirium and awareness were recorded.Results All patients were successfully awakened.There was no significant difference in wake-up time between the 2 groups (P ＞0.05).The incidences of hypertension,tachycardia,headache and awareness were significantly lower in group D than in group C (P ＜ 0.05).Conclusion Dexmedetomidine does not affect intraoperative wake-up time during operation on cerebral functional area performed under iv propofol-remifentanil anesthesia,but can significantly reduce the incidence of adverse effects.

The efficacy of laparoscopic Dixon operation for the treatment of rectal cancer has been proven,while at the same time there are opportunities to make the procedure less invasive.From January 2010 to March 2011,9 cases of single access laparoscopic Dixon operation have been performed at the Shengjing Hospital.An incision with the length of 3 cm was created in umbilicus and 3 trocars were inserted through the fascia on the abdominal wall.The dissection and anastomosis were performed through the incision.The resected tumors were removed through the umbilical incision or anus.The operation was successfully performed on 9 patients,and one more incision with the length of 12 mm was created on the lower abdominal wall in 1 patient in order to install the stapling device.The average operation time was 202 minutes.No postoperative bleeding,intestinal obstruction or anastomosis leakage was found.

Objective: To investigate the effects of culture medium osmolarity on the proliferation of human hepatoma cell line HHCC. Methods:Cell proliferation was analyzed by MTT assay and cell cycle analysis was carried out by flow cytometry. Results:Hyperosmolarity decreased significantly the absorbance (A) of HHCC cells and cell number, and hyposmolarity have counter effects. Compared with control, hyperosmolarity blocked cell cycle progression at the G 1 phase, while hyposmolarity accelerated cells into S phase from G 1 phase, and the effect of hyposmolarity was weakened by chloride channel blocker NFA. Conclusion:Culture medium osmolarity influenced the proliferation of HHCC cells by mediating cell cycle.

Objective To investigate the change of plasma marinobufagenin (MBG) level and the expression of its receptor Na+-K+-ATPase (NKA) in renal biopsy specimens of chronic glomerulonephritis (CGN) patients. Methods Twenty-eight CGN patients and 14 healthy people were enrolled in the study. The plasma MBG concentration was measured by competitive inhibition ELISA system. Immunofluorescence and immunohistochemistry staining were applied to detect the expression of NKA in renal biopsy specimens of 28 CGN patients and analyzed by semi quantitively. Results Compared with healthy controls, CGN patients had significant lower plasma MBG concentration [(0.579±0.214) nmol/L vs (0.715±0.154) nmol/L, P＜0.05], without further significant difference between CGN patients with hypertension and with normal blood pressure [(0.595±0.231) nmol/L vs (0.557±0.197) nmol/L, P＞0.05]. Meanwhile, proximal tubular staining of NKA was decreased compared with normal controls. The NKA positive staining area of the CGN group was lower than that of normal controls [2.1% (0.5%-6.2%) vs 5.6% (3.5%-10.8%), P＜0.01] and correlated with 24-hour urinary sodium excretion (r=0.551, P＜0.01).Conclusion Decreased plasma MBG level and its receptor expression on proximal tubules may play a role in the regulation of sodium in CGN.

Objective To explore the effects of repetitive transcranial magnetic stimulation (rTMS) on the motor function of lower limbs of patients with cerebral infarction.Methods Sixty stroke survivors with lower limb dysfunctionwere randomly assigned to an rTMS treatment group or a control group,each of 30.Both groups were given routine medication and rehabilitation treatment,while the treatment group was additionally provided with 4 weeks of rTMS treatment of the contra-lesional M1 at 1 Hz and 90％ motor threshold.The Fugl-Meyer motor assessment (FMA) and maximum walking speed (MWS) were used to assess both groups before and after the treatment and 2 weeks later.Adverse reactions were also recorded.Results Before the intervention,no differences were found between the two groups.After the treatment and two weeks after that,significant improvement was observed in the average FMA and 10 m MWS of both groups,with significantly more improvement in the treatment group than among the controls.No obvious adverse reactions were observed in either group.Conclusions rTMS can improve the motor function of the affected lower limbs of stroke patients safely.

AIM:To research inhibitory effects of plumepoppy (Macleaya cordata) extract on dermophytosis. METHODS:A series of experimental methods,including agar hole method,plate dilution method and solid medium dilution method were initiated into pathogenic organism of skin disease,including Trichophyton rubrum(Tru),Trichophyton schoenleini(Ts),Trichophyton rosaceum(Tro),Trichophyton mentagrophytes(Tm),and Epidermophyton floccosum(Ep) to determinate in vitro antibacterial Minimum inhibitory concentration(MIC) by plumepoppy extract that macerated with acidic water (pH = 3). RESULTS:Macleaya cordata alkaloids had significant effect on these five kinds of skin fungi. The MIC of Tru,Ts,Ep was 1. 6 mg/mL; The MIC of Tro and Tm was 0. 8 mg/ mL. CONCLUSION:The plumepoppy extract has anti-fungus activaties,with the increasing concentration,the inhibition effect rapidly goes up.