Non-uniform model of relationship between surface strain and rust expansion force of reinforced concrete.

When operating within the environments rich with sodium chloride, steel bars of reinforced concrete structures are often subject to corrosion caused by surrounding erosive materials, and the associated rust expansion force due to corrosion takes a critical role in determining the durability of relevant reinforced concrete structures. By investigating the corrosion course of steel reinforcement with theory of elasticity, a numerical rust expansion model is established for the moment of concrete surface rupture based on non-uniform sin function. Cuboid reinforced concrete specimen with squared cross sections is tested to analyze the rust expansion when concrete cracks due to corrosive forces. The utility of the established expansion model is validated by numerical simulation with Abaqus through the comparison between the associated outcomes. The impacts of steel bar diameter and concrete cover thickness on the magnitude of rust expansion force are discussed.

Short and medium term follow-up study on the changes of spine pelvic parameters in patients with hip-spine syndrome after total hip arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the influence of total hip arthroplasty on the changes of spine pelvic parameters in patients with hip spine syndrome.@*METHODS@#From January 2013 to October 2014, 22 patients (26 hips) with hip spine syndrome accompanied by necrosis of femoral head, hip osteoarthritis and congenital dysplasia of hip were treated with total hip arthroplasty. There were 12 males and 10 females with an average age of 58.4 years (range, 45 to 76 years). The course of disease was 1.5 to 25 years with an average of 12.8 years. Before and after the operation, the anteroposterior, full length radiographs of both lower limbs, thoracolumbar spine and pelvis in standing position were routinely taken. The balance parameters of spine pelvis coronal plane and sagittal plane before and after the replacement were measured. Visual analogue scale (VAS), Oswestry Disability Index (ODI) and Harris score were performed before and after the operation.@*RESULTS@#All cases were followed up for 21 to 52 (32±8) months. No infection, prosthesis subsidence, loosening, prosthesis dislocation were found in the last follow up. After total hip arthroplasty, sagittal vertical axis(SVA), thoracic kyphosis(TK), lumbar lordosis(LL), pelvic tilt (PT) were significantly reduced(@*CONCLUSION@#After total hip arthroplasty, the coronal and historical balance parameters of spine and pelvis are significantly improved, and the short term and medium-term effects are satisfactory.

Strategy of acetabular anteversion in total hip arthroplasty with lumbar degenerative kyphosis / 中国骨伤

OBJECTIVE@#To investigate how to place the anteversion of acetabular prosthesis more reasonably in patients with lumbar degenerative kyphosis.@*METHODS@#A total of 122 patients with degenerative kyphosis of lumbar spine who underwent total hip arthroplasty from December 2017 to October 2019 were included and divided into experimental group and control group, 61 cases in each group. In experimental group, there were 25 males and 36 females, with a median age of 67.0 years;the median course of disease was 46.0 months;the functional pelvic plane with acetabular anteversion was set according to different types of pelvic anterior plane bracket. In control group, there were 27 males and 34 females, with a median age of 67.0 years;the median course was 42.0 months;in control group, the anteversion was set by the traditional method. The patients were followed up for 3 months. The operation time and blood loss were recorded. The incidence of infection and dislocation within 3 months was counted. Harris score before and 3 months after operation was recorded. Functional anteversion angle of standing position was measured 3 months after operation.@*RESULTS@#Compared with control group, there was no difference in operation time and blood loss between the two groups (P=0.918, 0.381);there was no infection between two groups within 3 months after operation;there was 1 case of hip joint dislocation in the control group and no dislocation in experimental group. There was no significant difference in Harris score before and after operation. Three months later, reexamination of pelvic standing radiographs showed that the number of patients with functional anteversion of acetabular prosthesis outside the safe area was less in experimental group thanin control group (@*CONCLUSION@#According to the preoperative evaluation and classification of patients, better functional anteversion of acetabular prosthesis can be obtained with the help of pelvic anterior plane reference bracket in hip arthroplasty with lumbar degenerative kyphosis.

A Study of LPS Mediated Inflammatory Oxidation Reaction of Three Types of Rodents / 昆明医科大学学报

Objective By comparing with the SD rats mixed glial cells, C57 mice mixed glial cells and Kunming mice mixed glial cells and exploring the expression of inflammatory factor of three mixed glial cells induced by lipopolysaccharide (LPS), the study aimed to explore the application value of three kinds of mice and find the ideal model of inflammation. Methods We used LPS as inducers, and NO, IL － 1β, COX－2and iNOS as anti－inflammatory antioxidant index. After cutting the head and taking the brain, we cultured the mixed glials. Then we used Greiss assay to detect the expression of NO and used western blot to detect the expression of protein of IL－1β, COX－2, and iNOS protein.Finally we compared the mixed glial cells from SD rats, C57 mice mixed glial cells and Kunming mouse mixed glial cells and selected the best inflammation model from three mixed glial cells. Results The results showed that the morphological changes of the mixed glial cells in SD rats were treated with N2－ free medium. Compared with the control group, the quantity of NO of LPS group of three mixed glial cells increased significantly (P＜0.01) . The LPS group of SD rats released the highest concentration of NO. Western blot was used to detect the expression of IL－1β, Cox－2 and iNOS in three kinds of rodents. Compared with the blank control group, the expression of COX－2 protein, iNOS and IL－1β in the LPS group of the three mice increased significantly. The results showed that LPS could successfully stimulate the release of inflammatory cytokines in three kinds of mice,among which the SD rats were more sensitive and it could be used in the study of AD inflammation model. Conclusion The results showed that LPS could induce the release of NO and the expression of IL－1β, iNOS and COX－2 in C57BL/6 mice,Kunming mice and SD rats to induce inflammatory response. Thus,LPS can induce the formation of inflammatory oxidation models of the original mixed glial cells of the three mice. Moreover, the SD rats were more sensitive.

Comparison of therapeutic effects of three repair methods for rotator cuff tears under arthroscopy / 中国骨伤

<p><b>OBJECTIVE</b>To retrospectively study curative effects of three repair methods for rotator cuff tears under arthroscopy, and to explore relationships between different repair methods and cuff lesions.</p><p><b>METHODS</b>From January 2009 to Jaunary 2014, a total of 353 patients with rotator cuff tears treated with surgical repair under arthroscopy were included in this study. All the patients were divided into three groups according to time of visitiny hospital and it was divided into three periods. The patients on the first period were treated with single row rivet fixation(115 cases), including 51 males and 64 females, with an average age of (57.46±9.08) years old. The patients on the second period were treated with double row rivet fixation(163 cases), including 76 males and 87 females, with an average age of (56.93±9.92) years old. The patients in the third period were treated with suture bridge fixation(75 cases), including 32 males and 43 females, with an average age of (55.90±9.15) years old. There were 29 patients with huge rotator cuff injuries, who were treated with single-row suture. The shoulders were protected by a brace for 6 weeks after operations were permit ted to perform passive movement within 6 weeks, and then perform active shoulder exercise 6 to 10 weeks after operation. Constant-Murley score, UCLA score and VAS score were recorded preoperatively and postoperatively.</p><p><b>RESULTS</b>All the patients were followed up, and the duration ranged from 12 to 62 months, with a mean of 30 months. There was no infection or nerve injury. UCLA score was improved from preoperative 10.71±2.45 to postoperative 32.07±3.16; Constant-Murley score was improved from preoperative 43.33±11.55 to postoperative 78.15±12.64; VAS score was improved from preoperative 5.81±1.27 to postoperative 0.52±0.71. There were no statistical differences among three groups in UCLA score, Constant-Murley score and VAS score. Total 337 cases were satisfied with treatment results and 16 cases were not satisfied with the results. Among the 16 cases, 3 cases had huge rotator cuff surgery, and 13 cases had no joint stiffness before operation. The main complaints that resulted in dissatisfaction were weakness of the postoperative muscles and failure to restore the labour capacity(11 cases).</p><p><b>CONCLUSIONS</b>Rotator cuff repair under arthroscopy has a reliable clinical effect for the patients with rotator cuff tears. Stable and reliable clinical results can be obtained regardless different repair methods or different rotator cuff tears. The following factors such as no stiffness before operation, too early active exercise and preoperative rotator cuff atrophy may be the risk factors for postoperative dissatisfaction of patients.</p>

Analysis of delayed diagnosis of the vertical unstable pelvic fractures / 中国骨伤

<p><b>OBJECTIVE</b>To explore the causes of delayed diagnosis of the vertical unstable pelvic fractures in patients with multiple trauma so in order to minimize these incidence.</p><p><b>METHODS</b>A retrospective study was conducted in 176 patients with the vertical unstable pelvic fractures from January 2003 to December 2008. The classification of vertical unstable pelvic fractures was recorded. Medical data were compared and statistically analyzed to identify the incidence, and the contributing factors of the delayed diagnosis of the vertical unstable pelvic fractures. Of the 176 patients, 46 (26.1%) had delayed diagnosis of the vertical unstable pelvic fractures. There were 29 males and 17 females with an average age of 34 years old.</p><p><b>RESULTS</b>Of the factors contributing to 46 cases of delayed diagnosis, 41.3% (19/46) closely related to the evaluation by the doctors and were potentially avoidable, and 58.7% (27/46) were associated with the severity of the injuries.</p><p><b>CONCLUSION</b>The patients with multiple trauma had high incidence of delayed diagnosis of the vertical unstable pelvic fractures. The recognition of pelvic fractures, careful clinical assessments, and the awareness of the orthopedic doctors, emergency doctors and ICU doctors. Most of the delayed diagnosis of the vertical unstable pelvic fractures in patients with multiple trauma are potentially avoidable.</p>

Reconstruction of posterolateral structure in knee with Müller method / 中国骨伤

<p><b>OBJECTIVE</b>To study the clinical effects of Müller method for reconstruction of posterolateral corner (PLS) of knee joint.</p><p><b>METHODS</b>From June 2005 to June 2007, 13 patients with PLS injured were treated with Müller method. Four patients complicated with injuries in anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL), 7 patients complicated with injuries in PCL, 4 patient also had injuries in ACL, 1 patient complicated with ACL injury, and 1 patient complicated with avulsions fractures of the tibial ACL insertion. Among the patients, 5 patients had chronic injuries with a duration of 2 to 7 months. After the cruciate ligament was reconstructed, the popliteus tendon was reconstructed with iliotibial band and lateral collateral ligament (LCL) reconstructed with biceps femoris tendon. All the ligaments were fixed with interface screws. The patients were encouraged to do strength and motion exercise on bed immediately after operation and permit toe-touch weight-bearing till two months after operation. The brace was used till six months after operation.</p><p><b>RESULTS</b>The average follow-up period was 13 months (ranged from 6 to 27 months). There was no restriction of range of motion. External rotation range were good compared to the normal side. One year after operation, one-grade varus instability at 30 degrees flexion was found only in 2 patients. The postoperative Lysholm scores were from 77 to 94 (average 86).</p><p><b>CONCLUSION</b>The method is easier to perform, easier to get the materiar for reconstruction and promised satisfactory clinical results.</p>

Ligaments reconstruction for the treatment of lateral ankle instability / 中国骨伤

<p><b>OBJECTIVE</b>To study therapeutic effects of lateral ankle ligaments reconstruction for the treatment of chronic lateral instability of the ankle joint.</p><p><b>METHODS</b>From July 2005 to January 2008, among 13 patients with chronic lateral instability of the ankle joint, 10 patients were male and 3 patients were female, ranging in age from 24 to 45 years,with an average of 33 years. Anterior talo-fibular ligament (ATFL) and calcanea-fibular ligament (CFL) were anatomy reconstructed with a split peroneus brevis tendon graft for all patients. The ankle scoring system was used to evaluate ankle joint function before and after operation, which including stability, pain, locomotor activity and X-ray films.</p><p><b>RESULTS</b>All the patients were followed up ranged from 6 to 32 months, averaged 16.4 months. The postoperative scores of the ankles increased in respect to stability, pain and locomotor activity. The total average score increased from preoperative (43.54+/-7.04) to postoperative (73.38+/-4.17). There was significant difference between preoperative scores and postoperative scores (P<0.01). All the patients were satisfied with the results.</p><p><b>CONCLUSION</b>Anatomy reconstruct of the ATFL and CFL with a split peroneus brevis tendon graft (Sammarco method) is a practical method for lateral ankle instability and promise good results especially for patients complained of instability.</p>

Genetically marking of natural biocontrol bacterium Bacillus subtilis strains with green fluorescent protein gene / 生物工程学报

The full length sequence of the promoter and gfp gene were obtained respectively by PCR with two pairs unique primers PxyF/R and primers gfpF/R, which were designed according to the gfp gene and promoter sequence of xylase operon from Bacillus subtilis 168, and the DNA template plasmids pHT315-xyIR and pGFPuv. Furthermore, the fused translational expression cassette PxylR-gfp was constructed using overlapping PCR technique with the primers pair PxyF/gfpR and the mixture of above PCR production. After being digested by Kpn I and Sph I , PxylR-gfp expression cassette was inserted into E. coli-B. thuringiensis shuttle vecter pHT315 and E. coli-B. subtilis shuttle vecter pRP22, and the resulted recombinant plasmids were named as pGFP315 and pGFP22 respectively. Both recombinant plasmids were transferred into B. subtilis lab strain 168 and the resulted transformants are bright green performance under 365 nm UV light. However, only pGFP22 can be introduced into the natural strain B916. The transformants containing pGFP22 have bright green performance under 365 nm UV light and was named B916-gfp. Antifungal activities testing results proved that there is no obvious difference between B916 and the engineered strains B916-gfp. Research results also showed that the stability of B916-gfp was 94% after growth about 175 generations at 37 degrees C, and the losing rate of plasmid was less than 3.5 x 10(-4) per generation.

Studies on the microwave leakage of the interphone / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To assay and study the microwave leakage of 4 types of interphones.</p><p><b>METHODS</b>The radiation intensities of four types of 199 interphones were determined by the microwave leakage measure instrument of model ML-91 made in China.</p><p><b>RESULTS</b>The average intensities of microwave leakage at a distance of 5 cm from aerial part and other parts of interphones during launching [(1 316.0 +/- 144.3), (971.0 +/- 131.6) microW/cm(2) respectively] were significantly higher than during waiting [(14.4 +/- 5.3), (13.2 +/- 4.9) microW/cm(2) respectively] (P < 0.01). The average intensities of microwave leakage at a distance of 50 cm from different parts were (357.3 +/- 27.8) microW/cm(2). The daily average intensity of microwave leakage to which the head, chest and abdomen exposed was (945.5 +/- 447.1) microW.h/cm(2) in total, that exceeded the hygienic standard of microwave in China (400 microW.h/cm(2)), during the normal communication by interphones.</p><p><b>CONCLUSION</b>The microwave leakage was higher during launching than during waiting, and was the highest at the aerial part of the interphones. The microwave radiation of most interphones was higher than the current national standard. It may lead to potential effects on the owner of interphone, so protection against it should be made.</p>