船用腹部手术牵开器高强度塑胶钩板配件的研制

目的 研制与船用腹部手术牵开器相配套的高强度一次性使用的塑胶钩板.方法 根据临床使用船用腹部手术牵开器相配套的金属钩板时测得的拉力负荷值,通过工程力学和生物力学优化设计,优选高分子塑胶材料经注塑成型制成高强度一次性使用的塑胶钩板,并对制成的钩板进行耐高温热学和拉力学试验及临床使用验证.结果 选用医用聚甲醛树脂(polyformal dehyde,POM)制成与船用腹部手术牵开器相配套的高强度一次性使用的塑胶钩板,经耐高温热学和拉力学试验及临床使用验证,完全满足实际使用要求.结论 与船用腹部手术牵开器相配套的高强度一次性使用的塑胶钩板,质量轻、可拆卸、低成本且不丧失强度,特别适合平、战时舰船上批量手术时使用,该产品具备一定的高机械强度及耐高温性能,有一定的先进性和实用性.     

船用全方位腹部手术牵开器的研制

目的 研制更适合在舰船上手术使用的船用全方位腹部手术牵开器.方法 通过设计独特的手术床轨固定器,达到与已列装各种类型船用手术床的配套连接和使用.通过U形固定架总成的研制,比较其与临床上目前普遍使用的传统L形或S形牵开器在海上航行手术中的使用效果.设计、试制一次性使用无菌高分子钩板.结果 船用全方位腹部手术牵开器能与已列装各种类型船用手术床配套使用;且与传统腹部牵开器相比,安装、操作简便,术野暴露更好,牵拉控制更稳,手术人员节省更多.结论 船用全方位腹部手术牵开器更适合在舰船上手术时使用.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

单纯腹部外伤术后发生急性肾功能衰竭的危险因素分析

Objective To investigate the risk factors associated with acute renal failure (ARF)after surgery in patients with simple abdominal trauma. Methods A retrospective case-control study was carried out in patients with simple abdominal trauma after surgery from January 2003 through May 2008 in our hospital. Twenty patients with ARF were set as study group and 68 patients without ARF as control group. Clinical data including age, gender, injury type, number of injured organs, blood transfusion volume, intra-abdominal pressure, abdominal infection, shock and related factors were analyzed by using univariate and Logistic regression to identify the independent risk factors of ARF after surgery in patients with simple abdominal trauma. Results Univariate analysis revealed statistical difference in aspects of blood transfusion volume ( ＞ 1 600 ml), operation timing ( interval between trauma and operation ＞12 h), preoperative shock duration ( ＞6 h), postoperative abdominal infection and intra-abdominal hypertension ( ＞ 12 mm Hg) between two groups ( P ＜ 0. 05 ). Logistic regression analysis showed that these five indices were the independent risk factors of ARF after surgery in patients with simple abdominal trauma ( P ＜ 0. 05 ). Conclusions Massive blood transfusion, delayed operation, long preoperative duration of shock, postoperative abdominal infection or intra-abdominal hypertension are the risk factors of ARF after surgery in patients with simple abdominal trauma. We should pay attention to these factors and take effective measures to prevent occurrence of ARF.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαof small intestine in rats

Objective To observe effects of seawater immersion combined with open abdominal injury on the expression of NF-κB,and IκBαas well as the change pattern in rats. Methods Ninety-one Wistar rats were randomly divided into 3 groups: the control group (n =7), the open abdominal injury group(n =42) and open abdominal injury combined with 1-hour seawater immersion group ( n =42). The expression of NF-κB,andIκBαin small intestine tissues was measured by Western blot and statistical analyses were also made in the study. Results The expression of NF-κB,in the seawater immersion combined with open abdominal injury group increased significantly 3 hours after injury, when compared with that of the open abdominal injury group(P<0. 05), whereas the expression of NF-κB, of the pure injury group was slightly lower than that of the control group, but no statistical differences could be seen between them(P>0.05). The change pattern in the expression of IκBαwas quite the opposite to that of NF-κB. Conclusions NF-κB seemed to be rapidly and persistently involved in the whole inflammatory response to trauma induced by opened abdominal injury and seawater immersion, when a comparison was made with the pure open abdominal injury group. Injuries for the rats in the open abdominal injury combined with seawater immersion group were serious, and the feedback mechanism for NF-κB was not established for quite a long time.     

Significance of graft tension in anterior cruciate ligament reconstruction Basic background and clinical outcome

The purpose of this paper is to review scientific evidence that graft tension affects remodelling of the autograft in ligament reconstruction. The in situ freezing model of the patellar tendon, an ideal patellar tendon autograft model, demonstrated that subsequent cellular proliferation following fibroblast necrosis reduces the mechanical properties of the autograft. Stress shielding enhances reduction of the strength in the once-frozen patellar tendon. The strength of the patellar tendon also changes depending on the degree of stress shielding. Transmission electron micrographs revealed that the number of small-diameter fibrils decreases in the stress-shielded tendons compared with non-stress-shielded tendons after in situ freezing. Restressing essentially restores the mechanical properties of patellar tendon autografts even if the strength has been much reduced by complete stress shielding. The effects of restressing may depend on the period of stress shielding applied before restressing. Unphysiologically high tension significantly reduces the mechanical properties of the in situ frozen anterior cruciate ligament (ACL). Therefore, not only stress-deprivation but also stress-enhancement significantly affect the mechanical properties of tendon autografts. Results of in vivo and in vitro studies suggest that cyclic tensile loading may inhibit the deterioration in mechanical strength of the transplanted tendon. Clinically, our prospective randomized study demonstrated that a relatively high initial tension reduces the postoperative anterior laxity of the knee joint after ACL reconstruction using the doubled autogenous hamstring tendons connected in series with polyester tapes, when the tension applied is less than 80 N. Our experimental and clinical results indicate that the initial tension is one of the significant factors that affect the results of ACL reconstruction, although the optimal initial tension for the other graft materials still remains unknown.     

Development of a signal‐inducing bone cement for magnetic resonance imaging

Purpose:

To develop a signal‐inducing bone cement for musculoskeletal procedures in magnetic resonance imaging (MRI).

Materials and Methods:

Acrylic resins were mixed with contrast agents (CAs) and water. We determined the ideal concentration of the components and assessed feasibility in cadaveric bones in an open high‐field MR scanner. The contrast‐to‐noise ratio (CNR) in air and bone was evaluated and mechanical tests were achieved. We determined the amount of water that was not incorporated and measured the amount of CA released with photometric analysis. The cement was analyzed microscopically.

Results:

Preparation and application of the CA‐water‐cement compound was feasible and its differentiation in MRI was clear. The maximal CNR^air had a value of 157.5 (SD 18.3) in an interventional fast T1W turbo‐spin echo (TSE) sequence. The compressive strength decreased with the amount of water added. Although nearly 50% of the water added was not incorporated in the cement, the CNR was sufficient for cement detection. The threshold for systemic toxicity of delivered CA was not reached and the microscopic analysis showed water bubbles in the cement.

Conclusion:

A signal‐inducing bone cement is feasible for the use in MRI. J. Magn. Reson. Imaging 2010;31:636–644. © 2010 Wiley‐Liss, Inc.     

Effects of barium concentration on the radiopacity and biomechanics of bone cement: experimental study

Purpose  This study was undertaken to evaluate the changes in the radiopacity and mechanics of polymethylmethacrylate (PMMA) bone cement with the addition of barium. Materials and methods  Barium sulfate powder was added to a PMMA bone cement with an initial 10% barium concentration. The changes in radiopacity and strength were evaluated by testing cement blocks containing four barium concentrations (10%, 20%, 30%, 40%). Radiopacity was evaluated by measuring the computed tomography (CT) values of the bone cement, and strength was evaluated by compressive, three-point bending, and impact load tests. Results  CT values increased in proportion to the barium concentration. The compressive load test showed that cement with a 40% barium concentration was significantly more fragile than cement with lower barium concentrations. The three-point bending load test showed that the cement became more fragile in proportion to the barium concentration. The impact load test showed that cement with 30% and 40% barium concentrations was significantly more fragile than cement with 10% and 20% barium concentrations. Conclusion  Radiopacity is increased and strength is reduced by adding increasing concentrations of barium powder to bone cement. The results of the present study suggest that adding barium permits the radiopacity and strength of bone cement to be adjusted in clinical practice.     

Adolescent flexibility, endurance strength, and physical activity as predictors of adult tension neck, low back pain, and knee injury: a 25 year follow up study

Objective

To examine whether adolescent flexibility, endurance strength, and physical activity can predict the later occurrence of recurrent low back pain, tension neck, or knee injury.

Methods

In 1976, 520 men and 605 women participated in a sit and reach test (flexibility) and a 30 second sit up test (endurance strength). In 1976 and 2001 (aged 37 and 42 years) they completed a questionnaire. Lifetime occurrence and risk of self reported low back pain and self reported, physician diagnosed tension neck and knee injury were calculated for subjects divided into tertiles by baseline results of strength and flexibility tests.

Results

Men from the highest baseline flexibility tertile were at lower risk of tension neck than those from the lowest tertile (odds ratio (OR) 0.51, 95% confidence interval (CI) 0.28 to 0.93). Women from the highest baseline endurance strength tertile were at lower risk of tension neck than those from the lowest tertile (OR 0.60, 95% CI 0.40 to 0.91). Men from the highest baseline endurance strength tertile were at higher risk of knee injury than those from the lowest tertile (OR 1.96, 95% CI 1.05 to 3.64). Men who at school age participated in physical activity were at lower risk of recurrent low back pain (OR 0.61; 95% CI 0.42 to 0.88) than those who did not.

Conclusions

Overall good flexibility in boys and good endurance strength in girls may contribute to a decreased risk of tension neck. High endurance strength in boys may indicate an increased risk of knee injury.     

齿科用纤维加强树脂基复合材料表面纤维走向对粘接强度的影响

目的：比较齿科用纤维加强树脂基复合材料表面纤维走向对粘接强度的影响。方法将纤维加强树脂基复合材料切割成正方体试件,LuxaCore Z-Dual树脂水门汀粘接后扫描电镜下观察试件表面的纤维走向和粘接界面微观形态;将试件按粘接面纤维走向的不同分为A（横断面对横断面）、B（横断面对纵断面）、C（纵断面对纵断面）3组,每组20个标本,LuxaCore Z-Dual树脂水门汀粘接,万能测试仪测量剪切粘接力的大小。结果试件断面纤维方向均匀一致,粘接界面无气泡和裂隙;各组剪切粘接力比较,3组间差异无统计学意义（P>0.05）。结论粘接表面纤维走向对纤维加强树脂基复合材料的粘接强度无显著影响。     

Radicular canal disinfection by photosensitizers activated by photodynamic therapy and Er,Cr: YSGG laser bonded to glass fiber post using different cement types. An Invitro study

AimTo assess the tensile bond strength (TBS) of conventional glass ionomer cement (GIC) and resin cemented fiber post to radicular dentin when disinfected with different photosensitizers methylene blue photosensitizer (MBP), curcumin photosensitizer (CP), and laser therapy Er, Cr: YSGG laser (ECYL)Material and MethodsSixty carefully extracted, non-traumatic, non-carious, closed apex human mandibular premolars were collected. Periodontal fibers, plaque, or calculi were detached. Decoration of samples was executed up till the cementoenamel junction. Samples were embedded perpendicularly in a heat cure acrylic resin. Canals of all specimens were shaped and cleaned with Protaper universal NiTi system dehydrated with paper points and obturated with gutta-percha. Post space was prepared after the removal of gutta-percha via peso reamers. Post space was disinfected with MBPv100mg/L in group 1; group 2 500 mg/L and group 3 ECL. After sequential photo-irradiation therapies, fiber post was luted with resinous cement and GIC (n = 10 each). After post-cementation, all specimens were subjected to tensile strength in the universal testing machine in Newton. Failure analysis was assessed at 30x magnification.TBS determination was statistically analyzed by one-way variance analysis (ANOVA), followed by the Tukey test (p= 0.05) by parallelizing different groups.ResultsFiber post cemented to radicular dentin with Rely X ARC resin cement and radicular canal disinfected with CP offered the highest TBS (289.25±3.27 N). Similarly, canal space disinfected with MBP and post-luted via Rely X ARC showed the lowest TBS (281.54±4.46 N). Intragroup comparison unveiled that there is no statistical difference between tensile strength sustained by two luting cement (p>0.05).ConclusionRely X ARC resinous cement bared the highest tensile bond strength for a post-dentine-cement bond with different photo-activated canal disinfectants (Methylene blue photosensitizer, Curcumin photosensitizer) and Er, Cr: YSGG then Vidrion C (GIC).     

Efficacy of chlorhexidine,photosensitizers, green tea extract,and propolis on bond integrity and microleakage of caries-affected dentin: An in-vitro study

AimThe current study aimed to evaluate the efficacy of chlorhexidine (CHX), phycocyanin photosensitizer (PC), green tea extract (GTE), and propolis (PP) on the adhesive bond integrity and microleakage of caries-affected dentin (CAD) using etch and rinse adhesive system.Material and methodsA sum of 80 extracted human mandibular molars was collected and assessed using ICDAS criteria. Randomly CAD samples were treated with different disinfectants (n = 20) each CHX, PC, GTE, and PP. After ensuring disinfection, specimens were rehabilitated with bulk-fill composite resin employing etch and rinse adhesive system. SBS testing was performed by engaging (n=10) specimens in a universal testing machine. Microleakage analysis was performed by using the dye penetration technique.A stereomicroscope under 40× magnification was utilized for analyzing failure modes. Statistical analysis was accomplished by using the ANOVA and Tukey's post hoc tests (p<0.05).ResultsHighest bond strength was displayed by CAD disinfection with CHX and bonded to resin cement (15.33 ± 0.14 MPa). Whereas, the lowest SBS bond value was presented by Group 2 dentin surface disinfection with PC. CAD disinfected with GTE, PP and CHX demonstrated comparable SBS(p>0.05). The maximum microleakage score was exhibited when CAD bonded to resin cement disinfected with PP. While the minimum microleakage score was unveiled CAD bonded to resin cement sanitized with CHXConclusionCaries-affected dentin bonded to resin cement, chlorhexidine exhibited the highest adhesive shear bond strength with a minimal microleakage score using etch and rinse adhesive system.     

The effect of nonphysiologically high initial tension on the mechanical properties of in situ frozen anterior cruciate ligament in a canine model

An experimental study was performed in 32 adult beagle dogs to clarify the effect of nonphysiologically high initial tension on the mechanical and histologic properties of in situ frozen anterior cruciate ligaments. Both anterior cruciate ligaments in each dog underwent the in situ freeze-thaw treatment. The tibial insertion of the ligament was then made free from the tibia along with a cylindrical bone block. In the right knee, an initial tension of 20 N was applied on the anterior cruciate ligament by translocating the bone block in the distal direction. In the left knee, this bone block was anatomically reduced. Each bone block was firmly fixed with an interference screw. Ten animals were sacrificed at 6 weeks and 10 at 12 weeks. The tensile strength and the tangent modulus in the highly tensioned knee were significantly less than those in the physiologically tensioned knee at 12 weeks. Histologically, cell nuclei appeared to be spindle-shaped in the physiologically tensioned knee, while oval nuclei and focal degenerative changes with a number of vacuoles were occasionally found in the matrix in the highly tensioned knee. This study demonstrated that a nonphysiologically high tension significantly deteriorates the mechanical properties of the in situ frozen anterior cruciate ligament compared with physiologic tension.