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991.
目的探讨负压封闭引流技术治疗创伤性皮肤软组织缺损的临床效果。方法对2008年5月~2011年10月临床收治的37例复杂创伤性皮肤软组织缺损行手术清创,应用持续负压封闭引流技术覆盖创面,持续吸引治疗6~10d后,拆除敷料行二期植皮术。结果 37例患者中32例患者使用VSD治疗6~10d后行二期植皮全部成活;5例患者6~10d后再次行VSD治疗后植皮全部成活。结论 VSD能彻底清除创面的分泌物和坏死组织,刺激肉芽生长,明显缩短创伤性皮肤软组织缺损的治疗时间,减轻换药痛苦,效果显著。  相似文献   
992.
Introduction  Fracture triggers a cascade of systemic and local responses including inflammatory mediator signaling, chemotaxis, osteogenic cell recruitment, differentiation and proliferation at the fracture site. Early signaling between immune cells and repair cells in fracture repair is not well understood. Caveolin-1, a 21–24 kDa membrane protein plays key roles in transmembrane signaling. This study was to investigate the expression of caveolin-1 in human peripheral blood mononuclear cells (PBMNCs) following long bone fracture. Methods  PBMNCs were obtained from healthy volunteers or fracture patients at three time points following fracture by density-gradient-centrifugation procedure. Caveolin-1 gene expression and protein characterization was examined by semi-quantitative RT-PCR, immunocytochemistry and Western blot analysis. Results  Caveolin-1 mRNA and protein was expressed at low levels in the PBMNCs of non-fracture samples. In contrast, caveolin-1 expression was greatly increased in the PBMNCs of fracture patients 9–12 days and reduced at 16–21 days following long bone fracture. Conclusion  The identification of caveolin-1 in PBMNCs and osteoblasts makes this cellular domain a new focus for further investigation. We speculate that caveolin-1 expression in PBMNCs and osteoblasts play an important role in signal transduction during the early stages of fracture healing and may be an indicator for normal or abnormal fracture repair.  相似文献   
993.
Introduction  Selective and non-selective cyclo-oxygenase (COX) inhibitors impair bone healing by inhibiting prostaglandin synthesis. The purpose of this study was to evaluate the long-term effect of parecoxib, a selective COX-2 inhibitor, on bone healing in rats, when it is applied in a pattern similar to clinical treatment patterns, that is, in a high dose and for a short period after bone fracture. Method  Closed non-displaced mid-diaphyseal fractures in the middle of the left femoral shaft were generated in each animal. In the study group, parecoxib sodium (1.06 mg/kg) was administered intra-peritoneally every day for 7 days. In the control group, normal saline was administered intra-peritoneally every day for 7 days. In both groups fracture healing (bone union and callus formation) was evaluated with X-rays 28 and 42 days after surgery. Results  Bone healing was lower in the study group (60 vs. 80% in the control group 28 days after fracture and 80 vs. 90% 42 days after fracture) but this difference was not statistically significant (P > 0.05). Conclusion  Parecoxib does not have a significant long-term effect on bone healing in rats, when it is administered in a high dose and for a short period after bone fracture. Declaration  The experiments comply with the current laws of the EU, and the protocol was approved by the Local Ethics Committee on Animal Research.  相似文献   
994.
Purpose  Intestinal anastomotic healing is a complex procedure in which several mediators and cytokines play roles. Calcitonin gene-related peptide is an important neuropeptide in inflammation. In this study we aimed to investigate the effect of calcitonin gene-related peptide on healing of intestinal anastomosis in rats with obstructive jaundice. Materials and methods  Obstructive jaundice was induced in rats by the ligation and division of the common bile duct. Four days after the operation, intestinal anastomosis was performed, and either calcitonin gene-related peptide or 0.9% NaCl was administered intraperitoneally to these jaundiced rats and controls. The concentrations of serum tumor necrosis factor-α (TNF-α) and triglyceride levels of all rats were measured, and healing of the anastomosis was evaluated by measuring the bursting pressure and hydroxyproline content on the 7th postoperative day. Results  Calcitonin gene-related peptide was found to have positive effects on healing of the anastomosis by inhibiting the effects of TNF-α and increasing the bursting pressure and hydroxyproline content of the anastomosis. Conclusion  Calcitonin gene-related peptide increases anastomotic wound healing in experimental anastomosis in the presence of obstructive jaundice in rats.  相似文献   
995.

Background

Vacuum Assisted Closure (VAC; Kinetic Concepts, Inc., San Antonio, TX) has been used to successfully treat a variety of complex wounds. This technique was investigated for use in managing Fournier's gangrene following initial debridement.

Methods

Ten patients with Fournier's gangrene were treated in this study. After initial surgical debridement, 5 were treated using conventional therapy and 5 were treated with VAC at each dressing change. The effectiveness and cost of VAC for this indication were assessed; patient and physician satisfaction were also determined.

Results

Conventional and VAC treatment were equally effective in healing the wounds. The total costs of each treatment were similar. With the use of VAC, patients had fewer dressing changes, less pain, fewer skipped meals, and greater mobility. Hands-on treatment time was decreased for physicians using VAC.

Conclusions

VAC therapy is an effective and economical way to manage Fournier's gangrene. Patients and physicians were more satisfied with VAC therapy than with conventional treatment.  相似文献   
996.
Background  A successful deep multilayered wound suture should provide a firm tension-relieving closure, good wound-edge eversion, hemostasis, and minimal intradermal extraneous materials. However, this is not always achieved with a single standard technique. The authors describe their modification of a wound closure method that can rapidly and reliably achieve these results. Methods  A wedge-shaped excision was adopted to obtain a trapezoid pattern transect, after which a modified fully buried vertical mattress suture technique was used to close the wound. These techniques were compared with the standard excision and suture techniques used for the same patient at different times after surgery. Results  The wedge-shaped excision can facilitate good wound-edge eversion, and the modified fully buried vertical mattress suture can provide firm tension relief and optimal apposition. Compared with conventional excision and suture techniques, the described techniques brought about a better outcome in terms of hypertrophic scar prevention. Conclusion  The described modified technique seems to be more efficient than conventional procedures used to prevent hypertrophic scar formation.  相似文献   
997.
Background  Wound contractures can cause severe deformities and disabilities. Recent studies have suggested that leukotriene receptor antagonists have an inhibitory effect on the healing contraction process. This study aimed to evaluate the influence of the leukotriene inhibitor montelukast on the cutaneous healing process and the wound contraction phenomenon in rats. Methods  For this study, 60 male rats were randomly divided into four groups (MK-7d, SF-7d, MK-14d, and SF-14d) according to the drug given through a rigid orogastric tube (MK group: montelukast 10 mg/kg/day; SF group: normal saline solution) and the day the animals were killed (7d: postoperative day 7; 14d: postoperative day 14). An excisional wound (2 × 2 cm) was created on the dorsum of each rat. The wounds were left open to heal spontaneously and documented by standard digital photographs on different postoperative days. Wound contraction rates were calculated with specific software, and specimens were histologically evaluated using picrosirius red stain. Results were analyzed using the Aspin-Welch, Mann–Whitney, and t tests, assuming a significance level of 5%. Results  The wound contraction rates were similar between the control and study groups (p > 0.05). On postoperative day 7, the wounds showed a marginally significant reduction in collagen maturation in the study group (40.1% ± 6.88% vs 61.2% ± 8.02%; p = 0.0607). On postoperative day 14, this reduction was statistically significant in the MK group (26% ± 5.66% vs 68.3% ± 7.76%; p = 0.0001). Conclusions  Montelukast does not alter the contraction rate of excisional wounds in rats but has a significant and progressive inhibitory effect on collagen maturation. This study was developed by the Post-Graduate Program in Surgery and Plastic and Reconstructive Surgery Unit of Federal University of Paraná, Curitiba, Brazil.  相似文献   
998.
Hypertrophic nonunion usually results from insufficient fracture stabilization. Therefore, most hypertrophic nonunions simply require the stabilization of the nonunion site. However, the reasons why union occurs without treating the nonunion site directly is not well understood biologically. In this study, we hypothesized that the intervening tissue at the hypertrophic nonunion site (nonunion tissue) could serve as a reservoir of mesenchymal progenitor cells and investigated whether the cells derived from nonunion tissue had the capacity for multilineage mesenchymal differentiation. After nonunion tissue was obtained, it was cut into strips and cultured. Homogenous fibroblastic adherent cells were obtained. Flow cytometry revealed that the adherent cells were consistently positive for mesenchymal stem cell related markers CD13, CD29, CD44, CD90, CD105, CD166, and negative for the hematopoietic markers CD14, CD34, CD45, and CD133, similar to control bone marrow stromal cells. In the presence of lineage‐specific induction factors, the adherent cells differentiated in vitro into osteogenic, chondrogenic, and adipogenic cells. These results demonstrated for the first time that hypertrophic nonunion tissue contains multilineage mesenchymal progenitor cells. This suggests that hypertrophic nonunion tissue plays an important role during the healing process of hypertrophic nonunion by serving as a reservoir of mesenchymal cells that are capable of transforming into cartilage and bone forming cells. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:208–215, 2009  相似文献   
999.
Tendon injury frequently results in the formation of adhesions that reduce joint range of motion. To study the cellular, molecular, and biomechanical events involved in intrasynovial tendon healing and adhesion formation, we developed a murine flexor tendon healing model in which the flexor digitorum longus (FDL) tendon of C57BL/6 mice was transected and repaired using suture. This model was used to test the hypothesis that murine flexor tendons heal with differential expression of matrix metalloproteases (MMPs), resulting in the formation of scar tissue as well as the subsequent remodeling of scar and adhesions. Healing tendons were evaluated by histology, gene expression via real-time RT-PCR, and in situ hybridization, as well as biomechanical testing to assess the metatarsophalangeal (MTP) joint flexion range of motion (ROM) and the tensile failure properties. Tendons healed with a highly disorganized fibroblastic tissue response that was progressively remodeled through day 35 resulting in a more organized pattern of collagen fibers. Initial repair involved elevated levels of Mmp-9 at day 7, which is associated with catabolism of damaged collagen fibers. High levels of Col3 are consistent with scar tissue, and gradually transition to the expression of Col1. Scleraxis expression peaked at day 7, but the expression was limited to the original tendon adjacent to the injury site, and no expression was present in granulation tissue involved in the repair response. The MTP joint ROM with standardized force on the tendon was decreased on days 14 and 21 compared to day 0, indicating the presence of adhesions. Peak expressions of Mmp-2 and Mmp-14 were observed at day 21, associated with tendon remodeling. At day 28, two genes associated with neotendon formation, Smad8 and Gdf-5, were elevated and an improvement in MTP ROM occurred. Tensile strength of the tendon progressively increased, but by 63 days the repaired tendons had not reached the tensile strength of normal tendon. The murine model of primary tendon repair, described here, provides a novel mechanism to study the tendon healing process, and further enhances the understanding of this process at the molecular, cellular, and biomechanical level. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 833–840, 2009  相似文献   
1000.
In this study, we hypothesize that supplementation of suture repair of the anterior cruciate ligament (ACL) with platelet‐rich plasma (PRP) will improve the biomechanics of the repair. Six 30‐kg pigs underwent bilateral suture repair of the ACL. One side was treated with suture repair alone, while the contralateral side was treated with suture repair augmented with PRP. After 14 weeks in vivo, anterior–posterior (AP) knee laxity and the tensile properties of the repaired ligament were measured. The addition of PRP to the suture repairs did not improve AP knee laxity at 30° (p = 0.73) or 60° (p = 0.65). It also did not improve the maximum tensile load (p = 0.64) or linear stiffness (p = 0.42) of the ACL repairs after 14 weeks in vivo. The model had 80% power to detect a 30% improvement of biomechanical properties with PRP; thus, we are confident that a clinically meaningful effect as a result of adding PRP is unlikely. Use of PRP alone to supplement suture repair of the ACL is ineffective in this animal model. Published by Wiley Periodicals, Inc. J Orthop Res 27: 639–645, 2009  相似文献   
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