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Although often viewed as detrimental, fluctuations carry valuable information about the physical system from which they emerge. Femtosecond noise correlation spectroscopy (FemNoC) has recently been established to probe the ultrafast fluctuation dynamics of thermally populated magnons by measurement of their amplitude autocorrelation. Subharmonic lock-in detection is the key technique in this method, allowing us to extract the pulse-to-pulse polarization fluctuations of two femtosecond optical pulse trains transmitted through a magnetic sample. Here, we present a thorough technical description of the subharmonic demodulation technique and the FemNoC measurement system. We mathematically model the data acquisition process and identify the essential parameters that critically influence the signal-to-noise ratio of the signals. Comparing the model calculations to real datasets allows validating the predicted parameter dependences and provides a means to optimize FemNoC experiments.

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BACKGROUND: Pain after surgery, especially on the first postoperative day, results in longer hospital stays, increased complication rates and may also cause a higher risk of pain chronification. However, the expected intensity of pain is often misjudged and therefore not adequately treated. METHODOLOGY: An Austria-wide patient survey on the pain situation on the first postoperative day and on the quality of perioperative pain management was carried out on a voluntary and anonymous basis. RESULTS: Regarding the intensity of pain a clear gender difference could be observed. Women were more prone to more severe pain than men across all age groups. This difference was most pronounced in the younger age groups (18-40 years) and in those patients showing the highest pain scores. Treatment satisfaction was correlated (high significance) with pain intensity on exercise (p < 0.01), maximum pain (p < 0.01), least pain (<0.01) and frequency of postoperative pain assessment. DISCUSSION: The risk of postoperative pain can be reduced by optimal care structures. Since patients treated in optimal care structures had significantly lower pain scores on exercise and with respect to maximum pain, the investment in the optimization of such resources should be carefully planned. Special attention should be paid to postoperative pain management in women, especially in younger female patients.

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We investigate the nanostructure, the rheology and the adhesion of soft supramolecular materials elaborated by blending monofunctional and multifunctional poly(isobutene) (PIB) chains. Monofunctional PIB chains (PIBUT) are linear and unentangled polymer chains (Mn ≈ 3 kg mol-1) functionalized in the middle by a bis-urea interacting moiety, able to self-associate by four hydrogen bonds. Covalent coupling of monofunctional PIB allows us to synthesize longer chains bearing two or three interacting moieties. These chains are then added to monofunctional PIB to prepare blends containing up to 10% of multifunctional PIB (M-PIBUT). The influence of M-PIBUT on the supramolecular nanostructure, which results from the self-assembly of stickers, is studied by Atomic Force Microscopy and Small Angle X-ray Scattering at room temperature. Multifunctional and monofunctional chains are shown to interact with each other to form bundles of rod-like aggregates. The consequences of these interactions on the rheology of the blends were studied by shear tests in the linear and non linear regimes, below and above the order-disorder transition temperature. A pronounced strengthening effect of M-PIBUT is observed at room temperature: the supramolecular blends become more elastic and are more resistant to creep with increasing concentration of M-PIBUT. The effects of M-PIBUT on the nanostructure and the rheology suggest that M-PIBUT, which can link with more than one supramolecular aggregate, plays the role of a physical cross-linker. The impact of these supramolecular cross-linkers on the adhesion of the blends is studied by probe-tack tests and discussed by analyzing the in situ deformation through the debonding images.

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PURPOSE: Open anterior release of the external oblique fascia to enable midline closure of large abdominal wall defects is associated with relevant morbidity due to extensive subcutaneous dissection. Using endoscopic techniques, wound complications can be minimized. However, identification of the correct entry point (e.g. for balloon trocar insertion) can be challenging especially in adipose patients. We therefore present a technical modification facilitating the entire procedure. METHODS: A novel technique for endoscopic anterior component separation using a trocar system allowing blunt and sharp dissection under direct vision is described. This brief communication also contains our initial experience and learning curve with this novel approach. RESULTS: Endoscopic release of the external oblique fascia was successfully performed 29 times in a total of 15 patients. Body mass index accounted for 30.8 kg/m2 (median; range 21.6-42.5). Transverse width of midline defect accounted for 7 cm (median; range 4-12). Subsequent hernia repair was successfully done using sublay mesh reinforcement (n = 13) or a laparoscopic intraperitoneal onlay mesh procedure (n = 2) with midline closure in all cases. One hematoma was seen at site of release managed conservatively. CONCLUSIONS: Using a trocar system allowing blunt and sharp dissection under direct vision may be a viable option for the endoscopic anterior component separation.

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Despite many positive developments, postoperative pain and its treatment is still not always given the necessary attention. Severe pain after surgical procedures affects a significant proportion of patients. This very fact is not only detrimental to the immediate recovery process, but can also form the basis for the development of chronic pain conditions.An adequate and effective management of perioperative pain requires appropriate organizational structures. This multidisciplinary paper which was initiated by the Austrian Society for Anaesthesiology and Intensive Care and the Austrian Pain Society and developed together with numerous specialist and professional societies dealing with the subject aims at supporting the organization of perioperative pain management structures and to make best use of proven concepts. Additional recommendations describe specific interventions for selected types of intervention.

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AIM: Preclinical studies have suggested that nitinol-based compression anastomosis might be a viable solution to anastomotic leak following low anterior resection. A prospective multicentre open label study was therefore designed to evaluate the performance of the ColonRing(™) in (low) colorectal anastomosis. METHOD: The primary outcome measure was anastomotic leakage. Patients were recruited at 13 different colorectal surgical units in Europe, the United States and Israel. Institutional review board approval was obtained. RESULTS: Between 21 March 2010 and 3 August 2011, 266 patients completed the study protocol. The overall anastomotic leakage rate was 5.3% for all anastomoses, including a rate of 3.1% for low anastomoses. Septic anastomotic complications occurred in 8.3% of all anastomoses and 8.2% of low anastomoses. CONCLUSION: Nitinol compression anastomosis is safe, effective and easy to use and may offer an advantage for low colorectal anastomosis. A prospective randomized trial comparing ColonRing(™) with conventional stapling is needed.

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BACKGROUND: Little is known about factors which trigger and/or contribute to hereditary angioedema or ACE-inhibitor-mediated angioedema including variations in bradykinin type 2 receptor (B2R) expression and activity. METHODS: Protein and mRNA expression of B2R and the increase of intracellular calcium (iCa) in response to bradykinin were monitored in porcine and murine endothelial cells in response to NO donors or bradykinin. B2R protein expression was evaluated in skin, heart, and lung of (i) mice with endothelial-specific overexpression of eNOS (eNOS(tg) ), (ii) in eNOS(-/-) mice and (iii) in C57BL/6 mice treated with the NO donor pentaerythritol tetranitrate (PETN), the NOS inhibitor l-nitroarginine (L-NA), plasma pool C1-INH, and the B2R antagonist icatibant. Aortic reactivity to bradykinin was investigated including eNOS(-/-) mice. RESULTS: B2R protein and mRNA expression remained unchanged in cells subjected to L-NA, NO donors, and bradykinin in a time- and concentration-dependent manner. Likewise, increases of iCa in murine brain endothelial cells remained unchanged. B2R protein levels were similar in eNOS(tg) and eNOS(-/-) as compared to transgene-negative littermates. Likewise, treatment of C57BL/6 mice with PETN, L-NA, C1-INH or icatibant did not change B2R protein expression. In aortic rings of C57BL/6 mice, bradykinin induced B2R-dependent constrictions which were attenuated by endothelial NO and abolished by diclofenac indicating the functional importance of B2R-induced activation of endothelial NO synthase and cyclooxygenase. CONCLUSION: These data suggest that alterations of B2R protein expression induced by NO, bradykinin, C1-INH, or icatibant unlikely contribute to bradykinin-induced angioedema. This finding does not rule out a role for NO in bradykinin-induced extravasation and/or angioedema.

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AIM: Compression anastomosis has proved to be safe for rectal reconstruction with leak rates comparable to those observed using circular stapling devices. However, there are no data on whether the metallic compression ring alters the ease of diagnosis or the treatment in cases of leakage. In this study, we present our experience with early leakage following compression anastomosis. METHOD: A prospective registry was used for data review. Patients with anastomotic leakage following compression anastomosis between November 2008 and September 2013 were included. RESULTS: In all, 197 (92 female) patients were operated using a novel compression device. Early leakage was found in 10 (5.1%) patients after a median of 5 (3-14) days. The radiologist was able to detect leakage using CT in nine out of 10 cases unequivocally. Removal of the ring was necessary in eight of the 10 cases, and salvage of the anastomosis was feasible on six occasions. In all diverted cases with a low anastomosis, a transanal repair of the defect was feasible in three cases, including a single patient with complete separation of the anastomosis. CONCLUSION: Artefacts on the CT scan caused by the compression ring did not hamper the diagnosis of anastomotic leakage. Removal of the ring in the early postoperative period is not associated with complete separation of the bowel ends. Salvage of anastomosis is feasible in most cases.

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BACKGROUND: The current study was conducted to assess long-term outcomes after primary ileocolic resection for Crohn's disease (CD) and to identify factors associated with surgical relapse in the era of immunosuppressive medications. METHODS: Data were collected retrospectively on 116 consecutive patients, who underwent primary ileocolic resection for CD at a tertiary referral center between 1997 and 2006. Medical records were reviewed, and the use of immunomodulators was noted. The cumulative probability for a second operation due to recurrent CD was described by Kaplan-Meier curves. RESULTS: Ten patients (8.6 %) developed surgical recurrence after a mean follow-up period of 8.1 (±2.6) years. The percentage of patients not requiring further surgery was 96.5% and 88.0 % at 5 and 10 years, respectively. An urgent indication for surgery was significantly associated with the necessity of repeated intestinal resection (hazard ratio 5.6, 95 % confidence interval 1.2-27.0, p = 0.0145). In addition, postoperative exposure to azathioprine/6-mercaptopurine for more than 3 months decreased the probability of surgical recurrence significantly (hazard ratio 2.5, 95 % confidence interval 0.6-9.9, p = 0.0349). CONCLUSIONS: In contrast to previous studies, we observed a significant low surgical recurrence rate after primary ileocolic resection. Additionally, maintenance treatment with azathioprine/6-mercaptopurine after surgery may reduce the necessity for repeat surgical intervention.

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BACKGROUND: Tissue oxygenation is a strong predictor of surgical site infection (SSI). Mild intraoperative hypercapnia increases peripheral, gastrointestinal, and splanchnic tissue oxygenation and perfusion. Hypercapnia also has anti-inflammatory effects. However, it is unknown whether hypercapnia reduces SSI risk. We tested the hypothesis that mild intraoperative hypercapnia reduces the risk of SSI in patients having colon resection surgery. METHODS: With institutional review board approval and subject consent, patients having elective colon resection (e.g. hemicolectomy and low-anterior resection) expected to last >2 h were randomly assigned to intraoperative normocapnia (PE'CO2 ≈ 35 mm Hg; n=623) or hypercapnia ( PE'CO2 ≈ 50 mm Hg; n=592). Investigators blinded to group assignment evaluated perioperative SSI (Center for Disease Control criteria) for 30 postoperative days. SSI rates were compared. RESULTS: Patient and surgical characteristics were comparable among the groups. The SSI rate for normocapnia was 13.3%, and for hypercapnia, it was 11.2% (P=0.29). The Executive Committee stopped the trial after the first a priori determined statistical assessment point because of much smaller actual effect compared with the projected. However, because the actual difference found in the SSI rates (15-16%) were within the 95% confidence intervals (CIs) of the projected relative difference of 33% (95% CI -43 to +24%), our results cannot be considered as 'no difference', and cannot exclude a Type II error. Time to first bowel movement was half-a-day shorter in the hypercapnia group. CONCLUSIONS: Mild hypercapnia appears to have little or-possibly-no ability to prevent SSI after colon resection. Other strategies for reducing SSI risk should thus take priority.

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Erectile dysfunction (ED) is increasingly linked to coronary heart disease risk. Aim of this study was to test the hypothesis whether this association is due to penile atherosclerosis. We evaluated the prevalence and severity of penile atherosclerosis in relation to coronary and peripheral atherosclerosis. Between January and June 2010, a consecutive series of 31 men underwent an autopsy at the Department of Pathology at the Medical University Vienna. Atherosclerosis at the following localizations were histologically classified: right coronary artery, left coronary artery, left circumflex artery, internal iliac artery, dorsal penile artery and deep penile artery (bilateral). Coronary and peripheral atherosclerosis was present in 87.1 and 77.4% of cases. Atherosclerosis of penile arteries was detectable in only 4 men (12.9%). The only factor linked to penile atherosclerosis was diabetes (P=0.03). All other parameters as assessed according to medical history, general finding from autopsy or histological results regarding arterial lesions in general were not correlated to penile arterial lesions. In contrast to the high prevalence of atherosclerosis in general, penile arterial lesions are rarely present.

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AIM: Endorectal advancement flaps are an established treatment for high transsphincteric and suprasphincteric fistulae. The outcome of a repeat procedure in the case of flap breakdown and fistula recurrence remains unclear. The aim of the study was to analyse the outcome of repeat endorectal advancement flaps. METHODS: We retrospectively analysed patients with a repeat endorectal advancement flap procedure after flap breakdown and recurrence of fistula-in-ano of cryptoglandular origin who had been treated in our unit between 1994 and 2010. RESULTS: In all, 97 patients underwent an endorectal advancement flap procedure for fistula-in-ano and, of these, nine patients (five men, four women, 9.3%) subsequently underwent a repeat procedure due to flap breakdown. Median age was 40 years (range 25-60). Median follow-up time was 85 months (range 26-136). Seven full-thickness and two mucosal flap repeat procedures were performed because of eight transsphincteric and one suprasphincteric fistulae. The repeat procedure was successful in seven (78%) patients. In one of the two patients with repeat flap failure, a third flap procedure failed again. Disturbances of postoperative faecal incontinence were observed in five (55%) patients. Overall, the median postoperative Vaizey faecal incontinence score was 1 (range 0-4). CONCLUSION: Repeat endorectal advancement flap procedures are feasible and associated with a low recurrence rate and mild postoperative faecal incontinence. Therefore, a repeat procedure is a viable option in the case of a flap breakdown and fistula recurrence.

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BACKGROUND: Ileocecal interposition (ICI) for first-line reconstruction after low anterior colorectal resection was introduced by von Flüe and Harder in 1994 (Dis Colon Rectum 37:1160-1162, 1994). We report our experience using this technique to bridge colonic gaps after significant loss of bowel length. PATIENTS AND METHODS: Between 1999 and 2009 the left-sided colon was too short for traditional isoperistaltic reconstruction in six patients treated in our hospital. Reasons for extensive bowel loss were a deficient (n = 3) or torn (n = 1) marginal artery with ischemia or repeat colorectal resections (n = 2). An ICI was done to bridge the gap and enable restoration of intestinal continuity. RESULTS: No patient died. Whenever performing a coloanal anastomosis (4/6) a loop ileostomy was raised. One patient with colonic diversion experienced graft-related complications: ischemic colitis of the interposed colonic segment, anastomotic stenosis, and a presacral sinus were observed and managed nonoperatively. Subsequent closure of the stoma was possible in all cases. A median Vaizey incontinence score of 9 (range: 4-14) was recorded in the patient with coloanal anastomosis. The average number of bowel movements per day was 1.5 (range: 0.5-6). CONCLUSIONS: When the descending colon does not reach the rectal stump or anal canal in reoperative cases or after vascular complication, ICI is a useful salvage procedure resulting in good bowel function.

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More than 10 years ago, we developed an efficient protocol for serum-free retroviral transduction of human hematopoietic stem cells derived from mobilized peripheral blood. After upscaling of the methodology, serum-free retroviral gibbon-ape leukemia virus (GALV) pseudotype PG13/LN vector supernatant produced under strict good manufacturing practice (GMP) conditions was used in the first clinical gene-marking trial in Germany. In this study, we analyzed the titer and transduction efficiency of this serum-free clinical-grade retroviral supernatant 10 years after production to evaluate the long-term stability. Long-term storage and transport on dry ice resulted in modestly decreased titers and levels of transduction efficiency in CD34+ cells ranging from 38.4 to 49.1%. We conclude that the stability of retroviral vectors in serum-free medium allows extended storage and distribution of approved clinical-grade retroviral vector stocks to distant sites in multicenter clinical trials.

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AIM: The study investigated the fate of patients with perianal sepsis of cryptoglandular origin. METHOD: All patients treated for perianal sepsis between January 1994 and December 2000 were retrospectively analysed regarding recurrence and faecal incontinence. Data collection was conducted by chart review and by telephone questionnaire using the Vaizey incontinence score. RESULTS: One hundred seventy-three (58%) of 300 patients were available for follow-up at a median period of 121 (77-171) months. Fistula-in-ano was diagnosed in 156 (90%) patients. After a single surgical procedure, 55 (32%) patients had no recurrence of perianal sepsis. In 118 (68%), recurrence required multiple procedures (median 3, range 2-19). If only a single incision and drainage was performed (n = 10, 6%), no faecal incontinence occurred. Drainage with fistulotomy (n = 45, 26%) induced mild incontinence in 9% and severe incontinence in 4%. After multiple procedures that were required in 118 (68%) patients, mild and severe faecal incontinence was found in 16% and 4% of them, respectively. CONCLUSION: Treatment of anal sepsis is associated with a high recurrence rate and a substantial risk of faecal incontinence.

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AIM: There is growing evidence that stapled anastomoses are similarly effective compared to hand-sewn anastomoses in Crohn's patients. This study was designed to assess safety and limitations of wide-lumen stapled ileocolic anastomoses. METHOD: All patients with ileocolic resections for Crohn's disease perfomed between 1998 and 2006 were studied. A stapled anastomosis was constructed whenever possible. Potential risk factors for postoperative complications were recorded, retrospectively. Univariate and multivariate analyses were performed. RESULTS: In 209 out of 220 cases (95%, 132 primary operations) stapled anastomoses were performed. Eleven patients underwent a hand-sewn anastomosis owing to massive bowel dilatation (n = 7) or increased wall thickness (n = 4). There were 10 major (4.5%; surgical: 8, medical: 2) complications including two anastomotic leaks and one anastomotic bleed (all from stapled anastomoses) and one death not related to the anastomosis. Minor complications occurred in 25 patients. In multivariate analysis, major surgical postoperative complications were significantly associated with a low level of albumin (P = 0.0113) and previous resections for Crohn's disease (P = 0.0144). CONCLUSION: Stapled ileocolic anastomosis was safe in the majority of Crohn's patients. The most important limitation was technical impracticability. A low level of albumin and a history of previous resection increased the risk of postoperative complications.

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Superparamagnetic iron oxide nanoparticles, Fe(3)O(4) and gamma-Fe(2)O(3), were produced by the so-called polyol process. In order to stabilize the particles in a physiological environment as potential contrast agents for Magnetic Resonance Imaging (MRI), the as-prepared particles were successfully transferred to an aqueous medium through ligand exchange chemistry of the adsorbed polyol species with the dopamine or the catechaldehyde. The ligands were able to participate in bidentate binding to the nanoparticles surface and to improve the stability of aqueous suspensions of the nanoparticles. Analysis was performed by various techniques including X-ray diffraction, transmission electron microscopy, infrared spectroscopy and thermal analysis. The results of magnetic measurements and initial in vitro magnetic resonance imaging essays are presented for the pre- and post-surface modified nanoparticles, respectively and discussed in relation with their structure and microstructure.

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OBJECTIVE: Patients with slow transit constipation who do not respond satisfactorily to common medical treatment are considered candidates for colectomy. The present observational long term study was designed to assess outcome after surgery. METHOD: Twenty consecutive patients were treated by colectomy for slow transit constipation between 1996 and 2004. Preoperative and postoperative data were reviewed by using our institutional database. A questionnaire including validated scoring systems and questions about complications and subsequent surgical interventions was sent to all available patients. RESULTS: Three patients (15%) died perioperatively. Median long term follow up was 84 months. Ten patients (50%) needed further operations after colectomy: Three patients (15%) had surgery during the early postoperative period, seven patients (35%) during follow up. A total of 31 operations had to be performed in these patients. Twelve patients (86%) responded to the questionnaires. Their median Wexner constipation score was 11.5 (range 8-23). Six patients fulfilled the Rome II criteria for constipation. The median Vaizey incontinence score was 7.5 (range 0-22). The median GIQLI showed 80 points (range 32-129). CONCLUSION: Morbidity and mortality rate after colectomy were inadmissibly high. Taking into account the poor functional results, we cannot recommend colectomy for slow transit constipation.

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The purpose of this trial was to investigate the efficacy of adjuvant chemotherapy with 5-fluorouracil (5-FU) and leucovorin (LV) in stage II colon cancer. Patients with stage II colon cancer were randomised to either adjuvant chemotherapy with 5-FU/LV (100 mg m(-2) LV+450 mg m(-2) 5-FU weekly, weeks 1-6, in 8 weeks cycles x 7) or surveillance only. Five hundred patients were evaluable for analyses. After a median follow-up of 95.6 months, 55 of 252 patients (21.8%) have died in the 5-FU/LV arm and 58 of 248 patients (23.4%) in the surveillance arm. There was no statistically significant difference in overall survival (OS) between the two treatment arms (hazard ratios, HR 0.88, 95% CI 0.61-1.27, P=0.49). The relative risk for tumour relapse was higher for patients on the surveillance arm than for those on the 5-FU/LV arm; however, this difference was not statistically significant (HR 0.69, 95% CI 0.45-1.06, P=0.09). Consequently, disease-free survival (DFS) was not significantly different between the two trial arms. In conclusion, results of this trial demonstrate a trend to a lower risk for relapse in patients treated with adjuvant 5-FU/LV for stage II colon cancer. However, in this study with limited power to detect small differences between the study arms, adjuvant chemotherapy failed to significantly improve DFS and OS.

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BACKGROUND: Wound infection remains a common and serious complication after colonic surgery. Although many colonic operations are performed laparoscopically, it remains unclear whether this has any impact on the incidence of wound infection. Subcutaneous tissue oxygenation is an excellent predictor of surgical wound infection. The impact of open and laparoscopic colonic surgery on tissue oxygenation was compared. METHODS: Fifty-two patients undergoing elective open and laparoscopic left-sided colonic resections were evaluated in a prospective observational study. Anaesthesia management was standardized and intraoperative arterial partial pressure of oxygen was kept at 150 mmHg in both groups. Oxygen tension was measured in the subcutaneous tissue of the right upper arm. RESULTS: At the start of surgery subcutaneous tissue oxygen tension (PsqO(2)) was similar in both groups (mean(s.d.) 65.8(17.2) and 63.7(23.6) mmHg for open and laparoscopic operations respectively; P = 0.714). Tissue oxygen remained stable in the open group, but dropped significantly in the laparoscopic group during the course of surgery (PsqO(2) after operation 53.4(12.9) and 45.5(11.6) mmHg, respectively; P = 0.012). CONCLUSION: Laparoscopic colonic surgery significantly decreases PsqO(2), an effect that occurs early in the course of surgery. As tissue oxygen tension is a predictor of wound infection, these results may explain why the risk of wound infection after laparoscopic surgery remains higher than expected.

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