Prediction, analysis and application of learning curve of tooth preparation for all ceramic crowns of maxillary central incisors / 北京大学学报(医学版)

OBJECTIVE@#To predict the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training based on the modified Wright learning curve model, then to analyze and applicate the learning curve.@*METHODS@#Twelve graduate students participating in standardized dental resident training were selected to prepare the resin maxillary central incisors on phantom head simulators for all ceramic crowns 4 times. The results of preparation were evaluated by 3 prosthetic experts with at least 10 years' experience focusing on the reduction, contour, taper, shoulder, finish line, margin placement, adjacent tooth injury, and preparation time for tooth preparation. The learning rate of tooth preparation was calculated by scores of tooth preparation of 4 times. The learning curve of tooth preparation was predicted based on the modified Wright learning curve model. According to the criteria of standardized training skill examinations for dental residents in Beijing, 80 was taken as the qualified standard score. The minimum training times for tooth preparation to satisfy the qualified standard score (80) was calculated, to analyze the characteristics of learning curve and evaluate the effectiveness of tooth preparation.@*RESULTS@#The scores of 4 tooth preparation were 64.03±7.80, 71.40±6.13, 74.33±5.96, and 75.98±4.52, respectively. The learning rate was (106±4)%, which showed the learning curve an upward trend. There were no significant differences between the qualified standard score and the predicted scores of tooth preparation from the 5th preparation to the 13th preparation (P > 0.05). The predicted score of the 14th preparation was higher than the qualified standard score (P < 0.05).@*CONCLUSION@#The trend of the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training is upward, which predicts the minimum training times higher than the qualified standard score is 14 times.

Study of the changes in contrast sensitivity of eyes after laser in situ keratomileuses surgery among pilots / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the changes in contrast sensitivity (CS) between emmetropic pilots, glasses wearing, and after laser in situ keratomileuses ( LASIK) surgery pilots, provide the basis for the physical examination standard after operation. METHODS:The CS of 13 emmetropic pilots (26 eyes), 12 glasses wearing pilots (24 eyes) and 10 with LASIK (20 eyes) , under photopic, scotopic and scotopic with glare environments at four different spatial frequencies ( 3, 6, 12 and 18cpd ) were measured and the resluts were analyzed by statistics. RESULTS:Under photopic environments, there was no significant difference in the low spatial frequency (3cpd) among the three groups (P>0. 05). The CS of emmetropic pilots was better than that of the myopic and with LASIK, and there was significant difference (P0. 05). Under scotopic environments, there was no significant difference in the low spatial frequency (3cpd)among the three groups (P>0. 05). The CS of emmetropic and with LASIK pilots were better than that of the myopic, and there was significant difference ( P0. 05). Under scotopic with glare environments, the CS of emmetropic and myopic pilots were better than that of the with LASIK, and there was significant difference (P0. 05). CONCLUSION: The CS after LASIK is decreased compare with emmetropic pilot, specially under scotopic with glare environments. A perfect identification standard should be set up.

Anti-virus research of triterpenoids in licorice / 病毒学报

Licorice is a leguminous plant of glycyrrhiza. It is a traditional Chinese herbal medicine. Triterpenoid is one of the mainly active components of licorice. In recent years, the broad-spectrum antiviral activity of many triterpenoids in licorice was confirmed, and these findings have become a hot spot of antiviral immunity. The triterpenoids of licorice has the potential to become a novel broad-spectrum antiviral medicine and will be widely used in the clinical treatment. This review provided a summary of the recent anti-virus research progress on several triterpenoids in licorice, such as glycyrrhizic acid, glycyrrhizin, glycyrrhetinic acid and its derivatives. The antiviral roles of triterpenoids in licorice against herpes virus, HIV, hepatitis virus, SARS coronavirus and influenza virus were briefly summarized.

Induction of VEGF in human monocytes by DENV infection and the regulatory mechanism / 病毒学报

To investigate the effects of DENV infection on the expression of Vascular endothelial growth factor (VEGF) in monocytes, and to explore which innate immune signaling pathway is responsible for VEGF induction. Real-time PCR was used to determine the expression levels of VEGF in DENV-infected THP-1. We found that different serotype viruses (DENV1, DENV2, DENV3) induced the VEGF expression. Moreover, VEGF expression was significantly increased in human primary monocytes infected with DENV 2. In addition, VEGF induction by DENV2 was significantly impaired by knockdown of TLR3 and interferon-beta promoter stimulator 1 (IPS-1), or by inhibition of ERK, JNK or NF-kappaB. These results demonstrated that DENV induced VEGF expression in monocytes, and the activation of TLR3, IPS-1 signal pathways were required for DENV2-triggered VEGF induction, suggesting that VEGF might be a promising therapeutic target for DHF.

The comparative study of patients with severe polytrauma treated by damage control orthopedits in normal time and in earthquake / 中国骨伤

<p><b>OBJECTIVE</b>To compare the outcome of damage control in patients with severe polytrauma in normal time and in the earthquake of 2008 Sichuan China.</p><p><b>METHODS</b>In the retrospective study, 26 cases with severity polytrauma in peacetime and 24 cases with severe polytrauma who have mainly sustained in the earthquake of 2008 Sichuan China were involovd. The patients' demographics, the methods and effects of damage control were evaluated.</p><p><b>RESULTS</b>In the earthquake group, 24 cases succeeded in the rescuing life; among whom, 3 patients needed the further debridement and dermoplasty. In the normal time group, 26 cases succeeded in the rescuing life; among whom, 19 patients had returned to their former work and 3 patients needed the further treatment. There was no difference between two groups in therapeutic effects (P > 0.05).</p><p><b>CONCLUSION</b>Both in earthquake and in normal time, treating the severity polytrauma by damage control orthopedics can acquire satisfied effect.</p>

Repair of acutely injured spinal cord through constructing tissue-engineered neural complex in adult rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To construct tissue-engineered neural complex in vitro and study its effect in repairing acutely injured spinal cord in adult rats.</p><p><b>METHODS</b>Neural stem cells were harvested from the spinal cord of embryo rats and propagated in vitro. Then the neural stem cells were seeded into polyglycolic acid scaffolds and co-cultured with extract of embryonic spinal cord in vitro. Immunofluorescence histochemistry and scanning electron microscope were used to observe the microstructure of this complex. Animal model of spine semi-transection was made and tissue-engineered neural complex was implanted by surgical intervention. Six weeks after transplantation, functional evaluation and histochemistry were applied to evaluate the functional recovery and anatomic reconstruction.</p><p><b>RESULTS</b>The tissue-engineered neural complex had a distinct structure, which contained neonatal neurons, oligodendrocytes and astrocytes. After tissue-engineered neural complex was implanted into the injured spinal cord, the cell components such as neurons, astrocytes and oligodendrocytes, could survive and keep on developing. The adult rats suffering from spinal cord injury got an obvious neurological recovery in motor skills.</p><p><b>CONCLUSIONS</b>The tissue-engineered neural complex appears to have therapeutic effects on the functional recovery and anatomic reconstruction of the adult rats with spinal cord injury.</p>

Primary total hip arthroplasty for acetabular fracture / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore the operative indications and operative methods of primary total hip arthroplasty for acetabular fracture and to observe the clinical curative effect.</p><p><b>METHODS</b>We retrospectively summarized and analyzed the traumatic conditions, fracture types, complications, operative time, operative techniques, and short term curative effect of 11 patients (10 males and 1 female, with a mean age of 42.4 years) with acetabular fracture who underwent primary total hip arthroplasty.</p><p><b>RESULTS</b>The patients were followed up for 6-45 months (mean=28 months). Their average Harris score of postoperative hip joint was 78.</p><p><b>CONCLUSION</b>Under strict mastery of indications, patients with acetabular fracture may undergo primary total hip arthroplasty, but stable acetabular components should be made.</p>

Revision of infected total hip replacement:a report of 30 cases / 中华创伤杂志

Objective To retrospectively study revisions for infected total hip replacements in 30 cases and discuss the bacteriological characters of the infected total hip replacements,difficulties and strategies in the revision.Methods Thirty revisions of infected total hip replacements were reviewed retrospectively.There were 12 males and 18 females,with mean age of 62.5 years(31-86 years)at revi- sion surgery.Infection was presented one month to four years(mean seven months)after THA operation. The diseases for initial operation included femoral neck fractures in 12 cases,femoral head necrosis in 11,hip osteoarthritis in five and rheumatoid arthritis in two.Twelve eases were treated by one-stage revi- sion and 18 by two-stage revision.Results Before the revision operation,the hip infection were diag- nosed by bacterial culture in 18 cases including five with Staphylococcus epidermidis,four with Staphylo- coccus aureus and nine with other bacteria.Bacteria growth appeared on the specimens from 23 hip joints during the revision surgery but not on the specimens from seven hip joints.Of 12 one-stage revisions,10 cases were followed for mean 16 months,which showed infection recurrence in two eases.Of 18 two-stage revisions,13 cases were followed for mean 20 months,which showed one case with infection recurrence. The mean Harris hip score was improved from preoperative 44 to 84 at follow-up.Conclusions 1) The main bacteria in the infected hip are antibiotic resistant Staphylococcus.2)Because the revision op- eration is difficult,careful preparation before revision is important for success.The fresh surgeon should not attempt.3)The revision strategies should vary according to specific status of the cases.The infection recurrence rate is lower when using a two-stage revision strategy.4)Application of antibiotic bone cement can help improve treatment effect and facilitate functional recovery of the joints.5)The scientific rehabil- itation after operation is very important to functional recovery.

Application of microsurgical technique in joint replacement / 中华显微外科杂志

Objective To report the experience of the application of microsurgery in joint replace- ment.Methods There were 22 cases,10 cases with segmental acetabular defects treated with the pedicle sartorius muscle iliac bone grafting,5 cases with vascular repair following major vascular injury of extremity during operation,6 cases with neural repair following neural injury during operation,1 case with serious injury reconstruction by elbow joint replacement and free flap.Results The operations succeeded in 22 cases without any postoperative infection.The mean follow-up was 40.1 months (3-72 months) in 22 cases,in which the joint function improved and the operative result was satisfactory with no joint pain.Conclusion Microsurgical technique can reconstruct bone and tissue defect effectively in joint replacement.