Objective To investigate the cause of vertical root fracture in pulpless teeth, and advance the measures of prevention. Methods The clinical data of 20 vertical root fracture in pulpless teeth (17 patients) were collected. The status of the teeth and periodontium before therapy were reviewed, the position and direction of the root fracture were observed, the type and position of the restoration and the occludent station of the teeth were analyzed. Results It was revealed that vertical root fracture frequently occurred in the molars (16/20). Vertical root fracture were frequently found in front teeth(4/20) and premolars (5/20)among those with coronal integrity. Decrease of alveolar level of various degrees was found in 19 cases, among which 8 were mild, 7 moderate and 4 severe. Vertical root fracture mainly took place in molars after coronal restoration (6/7). Vertical root fracture would likely to occur no matter whether they would be worked as the abutment teeth of the removable partial denture or fixed prostheses. Early contact occurred in lateral bite (6 cases) was more susceptible to vertical root fracture than that occurred in centric bite (1 case). Conclusion The causes of vertical root fracture in pulpless teeth are complicated. Due to unfavorable outcomes, it is important to take precautions for vertical root fracture.

Objective To study the plasma antioxidant vitamin status in patients receiving enteral nutrition(EN) or parenteral nutrition(PN) after upper gastrointestinal surgery.Methods One hundred and twenty patients who underwent upper gastrointestinal cancer surgery were randomized into EN and PN group.The plasma vitamin A,vitamin E and ?-carotene levels pre-and post-operation and one week after clinical nutrition supplement were studied.Results Vitamin A and ?-carotene levels decreased significantly after surgery(P=0.03 and P=0.01,respectively).Vitamin E decreased 10 weeks after the nutrition,and it was significantly lower in the EN group than in the PN group(P0.05).Conclusions A decrease of antioxidant vitamins is induced by surgery and vitamin E is recommended to be given in nutrition supplement patients,especially in the patients receiving EN.

Objective To evaluate the intraoperative opioid-sparing effect of different frequency transcutaneous electrical acupoint stimulation (TEAS) in the patients undergoing video-assisted thoracoscopic pneumonectomy.Methods Eighty patients,aged 40-64 yr,weighing 50-90 kg,of ASA physical status Ⅰ-Ⅲ,scheduled for elective thoracoscopic pneumonectomy under general anesthesia,were randomly divided into 4 groups (n =20 each) using a random number table:control group (group Con),stimulation on Lieque (LU7)-Quchi (LI11)-Neiguan (PC6)-Hegu (LI4) at 2/100 Hz group (group 2/100 Hz),stimulation on LU7-LI11-PC6-LI4 at 2 Hz group (group 2 Hz),and stimulation on LU7-LI1 1-PC6-LI4 at 100 Hz group (group 100 Hz).The patients in group Con had the electrodes applied,but received no stimulation.In 2/100 Hz,2 Hz and 100 Hz groups,the patients received 2/100,2 and 100 Hz TEAS on LU7-LI11-PC6-LI4 acupoints ipsilateral to the surgery site,respectively,starting from 30 min before induction of anesthesia until the end of surgery,and the intensity was the maximum current that could be tolerated.Anesthesia was induced with iv midazolam,propofol,sufentanil and cisatracurim,and maintained with target-controlled infusion of remifentanil and propofol,continuous infusion of cisatracurim,and iv boluses of sufentanil when necessary.The target plasma concentration of propofol was adjusted to maintain BIS value at 40-60 during operation.The initial target effect-site concentration of remifentanil was 1 ng/ml,and adjusted to 4 ng/ml at skin incision.The concentration of remifentanil and consumption of sufentanil were adjusted to maintain Analgesia Nociception Index (ANI) at 50-70.When the concentration of remifentanil was increased to 4 ng/ml,ANI was still less than 50,and then 0.1 μg/kg sufentanil was given.The duration of operation and intraoperative consumption of remifentanil and sufentanil (the consumption of sufentanil was converted to the consumption of remifentanil producing the equivalent effect by 1:10) were recorded.Results The intraoperative consumption of remifentanil was significantly reduced in 2/100 Hz group as compared with Con,2 Hz and 100 Hz groups.There was no significant difference in the intraoperative consumption of remifentanil between Con group,2 Hz group and 100 Hz group.Conclusion The use of 2/100 Hz but not 2 and 100 Hz TEAS on LU7-LI11-PC6-LI4 significantly reduces intraoperative opioid consumption in the patients undergoing video-assisted thoracoscopic pneumonectomy.

Aim: To study the effect of Eudragit S-100, a pH-responsive polymer, on protein refolding level, using recombinant human keratinocyte growth factor-2 (rhKGF-2) as a model protein. Methods: The refolding of rh-KGF-2 was performed by directly diluting denatured rhKGF-2 into a refolding buffer containing different concentrations of Eudragit. The ability of Eudragit S-100 to enhance protein refolding level was investigated using MTT assay, reverse phase HPLC, fluorescence emission spectroscopy and circular dichroism spectroscopy. Results: The addition of Eudragit S-100 in the refolding buffer significantly increased the rhKGF-2 refolding yield to 71%, when dilution refolding was conducted at 0. 5 mg/mL rhKGF-2. The outcome from the refolding study showed possibility of a special interaction between rhKGF-2 and Eudragit, suggesting that the refolding-enhancing ability of Eudragit S-100 was due to this interaction between Eudragit S-100 and rhKGF-2. Mean while, the result showed that the concentration of urea was also an important factor for the optimization of the refolding in the presence of Eudragit. Conclusion: Eudragit S-100 can significantly increase the refolding level of rhKGF-2.

Objective To census the preoperative prevalence rate of deep venous thrombosis (DVT) and to evaluate the risk factors of DVT in senile osteoporotic hip fractured patients.Methods The object of study were patients aged 60 and above, and osteoporotic hip fracture by low energy injury in 2013.Based on medical records, all the patients with osteoporotic hip fracture were evaluated the signs and symptoms of DVT in 24 h, D-dimer test and underwent Doppler ultrasound screening of bilateral venous system in lower extremity after admission, and all the patients received preoperative prophylactic anticoagulation.Patients with popliteal and proximal level thrombus or floating thrombus underwent inferior vena cava (IVC) filter insertion.Outcome measures: age, gender, fracture type, D-dimer value in 24 h preoperatively, occurrence time of DVT and region, grade of preoperative American Society of Anesthesiologists, preoperative medical diseases.Results 702 of 946 hip fracture inpatients were comprised in this retrospective study.All were not founded any symptom or signs of DVT.All patients were took preoperative Doppler ultrasound screening and the results as follows: 36 of 302 patients (11.9％) with femoral neck fracture were proved preoperative thrombosis(13 male, 23 female), the average age was 72.7 year-old(range from 62-90 year-old), on the same side as the fractured hip in 31 patients, bilateral thrombosis in 5 patients.74 of 400 patients (18.5％) with intertrochanteric fracture were proved preoperative thrombosis(38 male, 36 female), the average age was 76 year-old (range from 60-95 year-old), on the same side as the fractured hip in 68 patients, bilateral thrombosis in 6 patients.The most prevalence rate of DVT were in the first day after osteoporotic hip fracture, 15 patients (41.7％) with femoral neck fracture and 38 patients (51.40％) with intertrochanteric fracture.There were more proximal level and multiple level involment thrombosis over 5 days after injury.The most thrombosis were proven at calf and popliteal vein.Conclusion The prophylaxis of DVT should be started even in the emergency department in senile patient with osteoporotic hip fracture.To avoid the risk factors, early surgery and early postoperative mobilization will be effective.

Objective To study the impact of physical stimulus on periosteal chondroplasia with an in- tention of reconstructing cartilage tissue that has a biomechanical function and can be created either entirely in vivo or in vitro and subsequently implanted into the patient.Methods A series of biomechanical test methods were designed in order to investigate the mechanical properties of engineered cartilage under a variety of mechanical stress stimulations.The periosteal explants were harvested from proximal medial tibias of New Zealand rabbits and secured onto poly-?-caprolactone(PCL)scaffolds.The composites(periosteum/PCL)were suspended in the spinner flask bioreactor and the spinner flask was located on the stirring machine.The stem cells were stimulated by fluid shear stress under magnetic bar stirring.Results In gross observation,the thickness and length of neo-cartilage with shear force stimulation were significantly greater than those without shear force.The direction of elongation was parallel with fluid flow direction,regardless of composite orientation.Secondary,two different zones based on various cell morphology and distribution were clearly observed.The thickness of the superficial zone was greater in samples exposed to high shear force compared with low shear force.The superficial zone protein and lubricant were found in the engineered cartilage under shear stress stimulation.Conclusion The results reveal that shear stress can not only influence proliferation and differentiation of stem cells,but also change chondrocyte morphology and increase extracellular matrix production.

Objective To investigate the effects of transcutaneous electrical acupoint stimulation (TEAS) on early postoperative lung function in patients undergoing video-assisted thoracoscopic pneumonectomy.Methods Sixty ASA physical status Ⅰ or Ⅱ patients whose preoperative forced expiratory volume in 1 second (FEV1) ＞ 1.5 L,scheduled for elective video-assisted thoracoscopic pneumonectomy under general anesthesia,were randomly divided into 3 groups (n =20 each) using a random number table:control group (group C),Lieque (LU7)-Quchi (LI11)-Neiguan (PC6)-Hegu (LI4) group (group S1),and Xinshu (BL1S)-Feishu (BL13)-PC6-LI4 group (group S2).TEAS was applied to the corresponding acupoints on the operated side for 30 min once a day starting from 30 min before induction of anesthesia until the end of surgery,and on 1 st and 2nd days after surgery in S1 and S2 groups.The frequency was 2/100 Hz,the intensity was the maximum current that could be tolerated,and the intensity was about 6-18 mA for LU7,LI11,PC6 and LI4,or about 20-35 mA for BL15 and BLI3.Patient-controlled intravenous analgesia was performed to maintain the score for the intensity of pain ＜ 4.Before and after surgery,forced vital capacity (FVC) and FEV1 were measured after the chest tube was withdrawn and the changing rate was calculated.Results FEV1 and FVC were significantly lower after surgery than before surgery in all the groups (P ＜ 0.05).There was no significant difference in FEV1 and FVC before and after surgery and the changing rate between the three groups (P ＞ 0.05).Conelusion TEAS (applied during surgery and within 2 days after surgery,30 min/d,2/100 Hz) provides no obvious improvement in early postoperative lung function for the patients undergoing video-assisted thoracoscopic pneumonectomy.

Objective To compare the intraoperative opioids-sparing effects of transcutaneous electrical acupoint stimulation (TEAS) of Lieque (LU7)-Quchi (LI11)-Neiguan (PC6)-Hegu (LI4) versus Xinshu (BL15)-Feishu (BL13)-PC6-LI4 in patients undergoing video-assisted thoracoscopic lobectomy.Methods Sixty ASA physical status Ⅰ or Ⅱ patients,aged 34-83 yr,weighing 50-93 kg,scheduled for elective video-assisted thoracoscopic lobectomy,were randomly divided into 3 groups (n =20 each):control group (group C),LU7-LI11-PC6-LI4 group (group S1),and BL15-BL13-PC6-LI4 group (group S2).TEAS was applied to the corresponding acupoints on the operated side starting from 30 min before induction of anesthesia until the end of operation in S1 and S2 groups.The wave length was 0.6 ms when the frequency was 2 Hz,and the wave length was 0.2 ms when the frequency was 100 Hz.The intensity was the maximum current that could be tolerated,and the intensity was 6-18 mA for LU7,LI11,PC6 and LI4,or 20-35 mA for BL15 and BL13.Anesthesia was induced with iv injection of midazolam,propofol,sufentanil and cisatracurium and maintained with target-controlled infusion of remifentanil and propofol,iv infusion of cisatracurium,and iv boluses of sufentanil when necessary.The plasma concentration of propofol was adjusted to maintain BIS value at 40-60 during operation.The initial effect-site concentration of remifentanil was set at 1 ng/ml and then adjusted to 4 ng/ml at skin incision,and the concentration of remifentanil and consumption of sufentanil was adjusted to maintain Analgesia Nociception Index (ANI) value at 50-70.If the concentration of remifentanil was increased to 4 ng/ml,ANI value was still less than 50,and then sufentanil 0.1 μg/kg was injected intravenously.The time of operation and intraoperative consumption ofremifentanil and propofol were recorded.Results Compared with group C,the intraoperative consumption of remifentanil was significantly decreased in S1 and S2 groups (P ＜ 0.05).There was no significant difference in the intraoperative consumption of remifentanil between group S1 and group S2 (P ＞ 0.05).There was no significant difference in the time of operation and intraoperative consumption of propofol between the three groups (P ＞0.05).Conclusion TEAS of LU7-LI1 1-PC6-LI4 provides similar opioids-sparing effects during operation as TEAS of BL15-BL13-PC6-LI4 in patients undergoing video-assisted thoracoscopic lobectomy.

OBJECTIVE:To systematically evaluate the efficacy and safety of simvastatin vs. pravastatin in the treatment of hy-perlipidemia,and provide evidence-based reference for the clinical treatment. METHODS:PubMed,Medline,EMBase,Cochrane Library and CJFD were retrieved to collect the randomized controlled trial(RCT)of efficacy and safety of simvastatin(test group) and pravastatin (control group) in the treatment of hyperlipidemia. The methodological quality of included studies was evaluated. The Rev Man 5.2 software was chosen for data analysis. RESULTS:14 RCT involving 1 019 patients were included. Meta-analysis showed that simvastatin had more significant effect in the decreasing of TC [MD=-0.34,95%CI(-0.52,-0.16),P<0.001] and LDL-C[MD=-0.31,95%CI(-0.45,-0.17),P<0.001] than pravastatin;and simvastatin and pravastatin had the similar effect in TG[MD=-0.06,95%CI(-0.18,0.05),P=0.28)] and HDL-C[MD=0.00,95%CI(-0.04,0.04),P=0.85]. Adverse drug reaction rate results showed they were similar[OR=0.70,95%CI(0.36,1.39),P=0.31]. CONCLUSIONS:Simvastatin is more effective in lipid-lowering than pravastatin with similar safety. Due to the limited number and low quality of included studies,it remains to be further verified with more reasonably designed,multi-center and large-sample studies.

The article has studied the application and the student-centered teaching mode in clinic medicine teaching and discussed how to cultivate students' self-learning ability and life-time learning skills by means of internet teaching,problem-base learning,case-studying and question-discussion.It has also pointed out that compared with the traditional teaching mode this teaching mode has advantages in cultivating innovative,pioneering and practical medical talents.