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971.
Our objective in this study was to report on the successful clinical use of a new perforator flap obtained from the proximal quarter of the anterolateral lower leg. Eight patients had the procedure either as a result of trauma (seven patients) or to treat Marjolin's ulcer (one patient). During the procedure, a line was drawn from the anterior fibular head to the anterior lateral malleolus. Then, using Doppler, a septocutaneous perforator from the fibular head to the proximal quarter point of the line was identified. The subfascial dissection was continued to the detected perforator. Along the perforator in the anterior intermuscular (peroneal) septum, a deep dissection was performed. The perforator was then separated and the flap harvested. The septocutaneous perforator was the perforator of the superficial peroneal nerve accessory artery in three cases, the perforator of the superior lateral peroneal artery in one case, and the perforator originating directly from the anterior tibial artery in four cases. Seven of eight cases were treated successfully. The results obtained were satisfactory, both aesthetically and functionally. This flap is a valuable alternative to the various perforator flaps from the lower leg. This flap has the advantage of being very thin, which makes it suitable for reconstruction of defects in the foot, ankle, pretibial area, and knee. However, one limitation of this procedure is that the diameter of the perforator was approximately 0.6-1.2 mm.  相似文献   
972.
SD大鼠MSX-2基因真核表达载体的构建与功能鉴定   总被引:1,自引:0,他引:1  
目的 构建SD大鼠颅颌面发育相关基因MSX-2与PcDNA 3.1融合的高效真核表达载体,为研究MSX-2基因的功能奠定基础.方法 根据SD大鼠MSX-2基因的核苷酸序列,设计并合成引物,采用PCR技术,扩增编码MSX-2基因,TA克隆到PMD18-T载体上,再亚克隆到真核表达载体PcDNA 3.1的BamHI和Xhol位点.对该重组体进行酶切鉴定,以及测序验证.重组体转染HEK293细胞,RT-PCR和Western blot检测重组MSX-2基因的RNA和蛋白表达情况.结果 重组真核表达载体PcDNA3.1-MSX-2经PCR扩增、酶切鉴定均显示有476bp左右的特异性基因片断,证明MSX-2基因正向插入真核表达载体中;碱基序列的测定证明重组质粒中含有SD大鼠的MSX-2基因序列.重组体转染HEK293细胞,RT-PCR和Western blot可检测到重组MSX-2基因的mRNA和蛋白的特异表达.结论 成功构建SD大鼠MSX-2基因的高效真核表达载体,为进一步研究MSX-2基因的功能及基因治疗奠定了基础.  相似文献   
973.
Background: Carbon monoxide (CO) is produced by reaction of isoflurane, enflurane, and desflurane in desiccated carbon dioxide absorbents. The inspiratory CO concentration depends on the dryness and identity of the absorbent and anesthetic. The adaptation of existing mathematical models to a rebreathing circuit allows identification of patient factors that predispose to more severe exposures, as identified by carboxyhemoglobin concentration.

Methods: From our companion study, the authors used quantitative in vitro CO production data for 60 min at 7.5% desflurane or 1.5% isoflurane at 1 l/min fresh gas flow. The carboxyhemoglobin concentration was calculated by iteratively solving the Coburn Forster Kane equation modified for a rebreathing system that incorporates the removal of CO by patient absorption. Demonstrating good fit of predicted carboxyhemoglobin concentrations to published data from animal and human exposures validated the model. Carboxyhemoglobin concentrations were predicted for exposures of various severity, patients of different sizes, hematocrit, and fraction of inspired oxygen.

Results: The calculated carboxyhemoglobin concentrations closely predicted the experimental results of other investigators, thereby validating the model. These equations indicate the severity of CO poisoning is inversely related to the hemoglobin quantity of a subject. Fraction of inspired oxygen had the greatest effect in patients of small size with low hematocrit values, where equilibrium and not the rate of uptake determined carboxyhemoglobin concentrations.  相似文献   

974.
BACKGROUND: The fate of exudative polymorphonuclear neutrophils (PMNs) at the local site after surgery is not well understood. We evaluated the fate and functions of exudative PMNs at the local site in patients who were undergoing major surgery. We also investigated the relation between PMN apoptosis and cytokine levels at the local site during the postoperative period. METHODS: Exudative PMNs were isolated from 11 patients during the postoperative period. Apoptosis, reactive oxygen intermediates (ROI) production, CD16, and tumor necrosis factor receptor expression of the PMNs were determined by flow cytometry. Cytokine levels in the drainage fluid were measured. RESULTS: Exudative PMN apoptosis was markedly inhibited on postoperative day 1 and then increased in a time-dependent manner. IL-6 and granulocyte macrophage colony-stimulating factor were significant factors to inhibit exudative PMN apoptosis; tumor necrosis factor-alpha and IL-10 were the factors to increase apoptosis. ROI production and CD16 expression of exudative PMNs were augmented when PMN apoptosis was inhibited in the early postoperative period. CONCLUSIONS: Exudative PMN apoptosis was inhibited after surgery; PMN function was augmented after surgery. Cytokines at the local site may modulate exudative PMN apoptosis. Exudative PMN apoptosis reflected the inflammatory response after surgery. Understanding the mechanisms of PMN apoptosis and its pathophysiologic significance at local inflammatory sites in vivo may help in the design of more rational treatments.  相似文献   
975.
976.
Bone inducing agent (BIA) isolated from Saos-2 human osteosarcoma cells was added to an artificial bone substitute composed of 980 degrees C-heated carbonate apatite (CAp) and Type I atelocollagen (AtCol) extracted from bovine tail skins (88/12 in wt/wt %), and a CAp-AtCol-BIA substitute was prepared as an osteoinductive bone substitute. Rat calvaria osteoblasts treated by the isolated BIA demonstrated significantly increased alkaline phosphatase (ALP) activity after 3 days (p < 0.05). In vitro cell attachment and proliferation and ALP activity were investigated for the bone substitute combined with BIA. Osteoblasts cultured onto the surface of the CAp-AtCol-BIA substitute demonstrated remarkable morphological changes such as radial spreading, flattening, and projecting filopodia after 5 days. In comparison with the substitute without BIA, osteoblasts grown in the BIA-combined CAp-AtCol substitute expressed significantly increased proliferation and ALP activity, respectively (p < 0.05). Both the substitutes combined with and without BIA were implanted into artificial defects created in rabbit radii. After 4 weeks, the CAp-AtCol-BIA substitute implanted lesion was completely replaced by regenerated host bone in radiological observation whereas the substitute without BIA was partially resorbed. No histologic abnormalities appeared in the substitute either with or without BIA.  相似文献   
977.
Objective To investigate the effect and mechanism by which PPARγ ligand, rosiglitasone, regulates the expression of CD40 and intercellular adhesion molecule 1 (ICAM-1) in the rat peritoneal mesothelial cells (RPMCs) induced by lipopolysaccharide (LPS). Methods RPMCs were harvested from Sprague-Dawley rat peritoneal cavity and maintained under defined in vitro conditions. The cells were randomly divided into groups as follows: medium, LPS (5 mg/L), LPS (5 mg/L)+BAY11-7085(5 μmol/L, NF-κB inhibitor), rosiglitazone (10 μmol/L or 20 μmol/L, peroxisome proliferator-activated receptor γ activator), LPS (5 mg/L)+rosiglitazone (10 μmol/L)+GW9662 (3 μmol/L, peroxisome proliferator-aetivatcd receptor γ antagonist), and LPS (5 mg/L)+vehicle (DMSO 0.2 ml/L). The expressions of CD40 and ICAM-1 RNA in RPMCs were examined by RT-PCR after 3 hour treatment, and the protein expressions of CD40, ICAM-1, p-NF-κB p65 and p-IκBα were examined by Western blot or immunofluorescence after 24 hour treatment. Results Following treatment with LPS, both the expressions of CD40 and ICAM-1 protein in RPMCs were up-regulated significantly (P<0.05), and the phosphoralation of p65 was increased greatly (1.10±0.17 vs 0.55±0.06, P<0.05). BAY11-7085 (5 μmol/L) significantly decreased the protein expression of p-p65 (0.22±0.11 vs 1.10±0.17, P<0.01), CD40 (0.34±0.02 vs 0.50±0.06, P<0.05) and ICAM-1 (0.35±0.16 vs 0.74±0.03, P<0.05). Pretreated with rosiglitazone for 3 h then added with LPS for 1 h, the levels of p-p65, CD40 and ICAM-1 in RPMCs were significantly decreased compared with those of LPS group (0.77±0.08 vs 0.90±0.10, P相似文献   
978.
目的 探讨聚丙烯网塞及补片在腹股沟疝修补术(疝环充填式无张力疝修补术)中的优点,并总结经验教训。方法 采用美国巴德公司的聚丙烯锥形充填物及成型补片对102例腹股沟疝病人施行疝环充填式无张力疝修补术。观察手术时间、伤口疼痛、术后自主能力的恢复、并发症及复发率。结果 手术时间平均31.5min;术后4-6h病人能下床活动。伤口疼痛时间2-3d。术后排尿困难1例,伤口积液2例,无一例切口感染。腹股沟部异物感9例。术后获随访89例,仅1例复发。结论 锥形充填物及成型补片组织相容性好,无排异反应,具有一定的抗感染能力,是理想的疝修补材料,测环充填式无张力疝修补术手术操作简便,损伤轻,恢复快,术后复发率低,并可放宽手术指征,是较先进的疝修补术式。  相似文献   
979.
目的 :研究肢体延长过程中延长区内源性BMP、TGF β1蛋白表达情况。方法 :采用兔胫骨干骺端截骨延长模型 ,通过免疫组化方法研究延长区内源性BMP、TGF β1蛋白表达情况。结果 :BMP、TGF β1主要表达在软骨细胞、成骨细胞、成纤维细胞中。BMP在开始延长后前 2周高度表达 ,2周后表达逐渐降低 ;停止延长 1周时在延长区中央见到少量的阳性表达细胞 ,停止延长 2周时 ,随着延长中央区域纤维组织消失 ,BMP阳性表达细胞也消失。TGF β1在延长前2周表达逐渐增强 ,到 2周时最强 ,2周后逐渐减弱 ,并在延长及停止延长期间均可见阳性表达细胞。结论 :肢体延长中延长区内源性BMP、TGF β1持续表达。  相似文献   
980.
Anterior cervical discectomy   总被引:2,自引:0,他引:2  
  相似文献   
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