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21.
Sait Demirkol M.D. Ugur Kucuk M.D. Oben Baysan M.D. Sevket Balta M.D. Turgay Celik M.D. Ibrahim Halil Kurt M.D. Hilal Olgun Kucuk M.D. Uygar Cagdas Yuksel M.D. Murat Unlu M.D. Mehmet Yokusoglu M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1064-1070
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle. 相似文献
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The gluteal perforator-based flap in repair of pressure sores. 总被引:5,自引:0,他引:5
Cilingir Meltem Celik Esra Findik Hasan Duman Ali 《British journal of plastic surgery》2004,57(4):342-347
The gluteal perforator-based flap is designed according to the localisation of sacral perforator vessels. These vessels penetrate the gluteus maximus muscle and reach the intrafascial and suprafascial planes, and the overlying skin forming a rich vascular plexus. The gluteal perforator-based flaps described in this paper are highly-vascularised, have minimal donor site morbidity, do not require the sacrifice of the gluteus maximus muscle and rarely lead to post-operative complications. We believe these easy-to-perform flaps might be considered as the first choice in the repair of gluteal pressure sores. 相似文献
25.
BACKGROUND: The authors' aim is to understand the influence of human leukocyte antigen-DR positive microvascular (MV)-DR destruction on steroid and OKT3 response in acute rejection (AR). METHODS: Twenty of 40 patients had steroid-resistant AR (group 1) and received OKT3 treatment, and the other 20 patients had AR that responded to steroid treatment (group 2). A renal biopsy specimen was obtained from each subject during the AR episode. The degree of MV-DR destruction and the peritubular capillary (PTC) leukocyte infiltration were recorded in each case, using three-tiered scales. The follow-up biopsy specimens of all cases were evaluated for the development of interstitial fibrosis (IF). RESULTS: Seventy-eight percent of the cases with severe MV destruction and 45% of those with moderate MV destruction did not show response to steroid therapy, whereas 74% of the cases with mild MV destruction responded to steroid therapy. Group 1 patients showed higher frequencies of vascular rejection (80%) and high-grade PTC leukocyte infiltration (85%) than the group 2 cases (P<0.01 for both). Seventy percent of the patients in group 1 responded to OKT3 therapy. The biopsy specimens from the six individuals who were resistant to OKT3 had shown severe MV destruction, vascular rejection, and high-grade PTC leukocyte infiltration. Severity of MV destruction in the initial AR diagnostic biopsy was positively correlated with development of diffuse IF and chronic allograft nephropathy in the follow-up biopsy specimens (P<0.001) CONCLUSIONS: Analysis of MV destruction may be helpful for diagnosing rejection and predicting graft prognosis. This type of assessment may be useful for determining the immune response and thus identifying the most appropriate treatment. 相似文献
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Effect of intra-abdominal pressure level on gastric intramucosal pH during pneumoperitoneum 总被引:1,自引:0,他引:1
Celik V Salihoglu Z Demiroluk S Unal E Yavuz N Karaca S Carkman S Demiroluk O 《Surgical laparoscopy, endoscopy & percutaneous techniques》2004,14(5):247-249
The present study was designed to examine the effect of intra-abdominal pressure level on gastric intramucosal pH using gastric tonometry during pneumoperitoneum. One hundred patients were prospectively randomized into 5 equal groups (N = 20 each). Intra-abdominal pressure levels were 8, 10, 12, 14, and 16 mm Hg in groups I, II, III, IV, and V, respectively. Intramucosal pH measurement was done 2 times: 30 minutes following insufflation and 1 hour after the ending of the surgery. In the first and second measurements, intramucosal pH values were found as 7.39 +/- 0.02 and 7.36 +/- 0.03 in group I; 7.41 +/- 0.03 and 7.38 +/- 0.03 in group II; 7.37 +/- 0.03 and 7.37 +/- 0.03 in group III; 7.36 +/- 0.03 and 7.37 +/- 0.03 in group IV; and 7.39 +/- 0.03, 7.36 +/- 0.03 in group V, respectively. Statistical significance was not found in the comparison of these values within the groups and between the groups (P > 0.005, for each). In conclusion, intra-abdominal pressure between 8 and 16 mm Hg did not cause significant difference in gastric intramucosal pH. 相似文献
27.
Atilla Celik Ersin Ergun Neset Koksal Aysun Simsek Celik Ediz Altinli Mehmet Ali Uzun Ersan Eroglu Ahu Kemik 《American journal of surgery》2013
Background
The aim of this study was to examine whether treatment with montelukast, a selective leukotriene antagonist, would affect anastomotic healing in a reperfused colon rat model with remote ischemia/reperfusion injury.Methods
Rats (n = 12 per group) were intraperitoneally administered normal saline or 10 mg/kg montelukast sodium 60 minutes before and for 5 days after surgery. Ischemia was induced for 45 minutes through superior mesenteric artery occlusion. A left colon anastomosis was made. Blood and perianastomotic tissue samples were obtained on postoperative day 5.Results
Mean anastomotic bursting pressures of the control and montelukast groups were 159.17 ± 29.99 and 216.67 ± 26.40, respectively (P < .001). Compared with saline, montelukast treatment increased the mean tissue hydroxyproline level (2.46 ± .30 vs 3.61 ± .33 μmol/L) and decreased tissue caspase-3 activity (36.06 ± 5.72 vs 21.78 ± 3.87) and malondialdehyde levels (3.43 ± .34 vs 2.29 ± .34 nmol/g) (P < .001 for all). Other plasma markers of injury also showed differences.Conclusions
Montelukast prevented ischemia/reperfusion-induced damage in a rat model of colonic anastomotic wound healing. 相似文献28.
目的:研究二甲双胍(metformin,Met)联合培美曲塞(pemetrexed,Pem)对人肺腺癌A549细胞株的增殖及凋亡的影响。方法:不同浓度Met(0、2.5、5.0、10.0、20.0、40.0 mmol/L)、Pem(0、0.5、1.0、2.0、4.0、8.0 μmol/L)48 h下处理A549细胞,CCK?8法检测细胞增殖率并确定Met及Pem的半抑制浓度(IC50);Met(IC50)及Pem(IC50)单用或联用,不同时间(24、36、48 h)下处理A549细胞,CCK?8法检测细胞增殖率;流式细胞术检测细胞凋亡率;Western blot 检测Bcl?2、Bax、Mcl?1、Noxa蛋白表达。结果:①不同浓度Met及Pem对A549 细胞均有增殖抑制作用,呈剂量依赖性(P<0.05);②Met+Pem组作用A549细胞增殖抑制率优于单药组(P<0.05),呈时间依赖性(P<0.05);③Met+Pem组作用 A549细胞的凋亡率(30.6 ± 0.4)%优于Met组凋亡率(13.3 ± 0.3)%和Pem组凋亡率(12.9 ± 0.1)%(P<0.05);④与单药组相比,Met+Pem组明显下调Bcl?2、Mcl?1蛋白表达,上调Bax、Noxa蛋白表达(P<0.05)。结论:Met联合Pem可抑制A549细胞增殖、诱导凋亡,其效果优于单药,机制可能与下调Bcl?2、Mcl?1蛋白,上调Bax、Noxa蛋白的表达有关。 相似文献
29.
Incorporation of rician noise in the analysis of biexponential transverse relaxation in cartilage using a multiple gradient echo sequence at 3 and 7 tesla 下载免费PDF全文
30.
Vascular Endothelial Growth Factor Expression and Cyclosporine Toxicity in Renal Allograft Rejection 总被引:3,自引:0,他引:3
B. Handan Özdemir F. Nurhan Özdemir Nihan Haberal Remzi Emiroglu Beyhan Demirhan Mehmet Haberal 《American journal of transplantation》2005,5(4):766-774
The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term. 相似文献