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51.
A 70‐year‐old man with a history of coronary artery bypass grafting 15 years back and arteriovenous (AV) fistula creation in the left arm 1 month back presented with acute coronary syndrome (ACS). He had not received dialysis before his referral. We felt the most likely etiology for these complaints was increased cardiac oxygen demand from an increased cardiac output related to the newly formed left AV fistula. Coronary angiography was done to detect any significant stenosis in the native or grafted vessels. This revealed that the left subclavian artery was totally occluded in the ostioproximal segment and the coronary arteries did not have occlusions to explain the ACS setting. CT angiography confirmed the angiographic findings of the totally occluded left subclavian artery followed by a well‐developed and patent left internal mammary artery to left anterior descending artery. This led to the consideration of a steal syndrome from the coronary artery by the subclavian artery distal to the occlusion. A successful percutaneous endovascular intervention on the left subclavian artery occlusion was performed. Subsequently, the patient became asymptomatic and experienced a dramatic increase in left ventricular ejection fraction.  相似文献   
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Background

The aim of this trial is to prospectively evaluate the outcomes of PCL reconstruction by means of quadruple hamstring tendon autograft with a double-fixation method at minimal 3-year follow-up.

Materials and methods

Only patients who underwent PCL reconstruction without any other concomitant injury were included in this study. A hamstring tendon graft is composed of a quadruple-stranded gracilis tendon and semitendinosus tendon about 10 cm in length. An arthroscopic technique via a two incision and a double-fixation method was applied. Clinical evaluations were performed for 52 patients. Clinical assessment of patients included the Lysholm knee scores, International Knee Documentation Committee (IKDC) scores, thigh muscle evaluation, and radiographic investigation.

Results

On the Lysholm knee score, 90 % of the patients displayed good or excellent rating in the final assessment. In the IKDC rating analyses, 60 % of the patients demonstrated 3–5-mm ligament laxity. For the IKDC final rating, 81 % were normal or nearly normal. Seventy-nine percent of the cases revealed less than a 10-mm difference in thigh girth between their reconstructed and contra lateral limbs.

Conclusion

Arthroscopic PCL reconstruction using quadruple hamstring tendon autograft provides acceptable outcomes at a minimum 3-year follow-up. The four-stranded hamstring tendon graft is suitable in graft size and results in minimal harvesting morbidity. We recommend that quadruple hamstring tendon graft be chosen for PCL reconstruction to achieve good ligament reconstruction. A double-fixation method which has been applied in this trial can be used to provide rigid fixation.  相似文献   
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The liver function and perfusion following brain death is mainly influenced by the sympathetic nerves and hormones. We examined the specific influence of surgical liver denervation on systemic and hepatic perfusion parameters, bowel ischemia and oxidative stress in hemodynamically stable BD and control (living donor [LD]) pigs. Brain death was induced in 8 pigs via saline infusion into the balloon of an epidural Tieman-catheter (1 mL/15 minutes) and compared to the control group (n = 6) over 4 hours. At 2 hours postoperatively, complete liver denervation was initiated. We analyzed systemic cardiocirculatory parameters (mean arterial pressure, aortic flow, bowel ischemia (endotoxin, and endotoxin-neutralizing capacity) and oxidative stress (total glutathione in erythrocytes [tGSH(E)]) and compared them to local/hepatic perfusion parameters (hepatic artery and portal venous flow, liver blood flow index, and microperfusion), local bowel ischemia (intramucosal pH [pHi] of stomach [pHi(S)]/colon[pHi(C)]), and liver oxidative stress (glutathione [rGSH(L), GSSG(L)]). Following brain death, the parameters including mean arterial pressure, aortic flow, pHi, endotoxin, and tGSH(E) showed no significant changes at 2 hours. Portal venous flow and microperfusion were decreased significantly and hepatic arterial buffer response was ineffective. Hepatic oxidative stress was increased in BD animals (decrease rGSH(L), increase GSSG(L)). Surgical denervation/manipulation increased portal venous flow significantly, hepatic arterial buffer response became effective, and stomach pHi decreased (BD and LD groups). Hepatic oxidative stress was reduced in the BD group (increase rGSH(L)/GSSG(L); P < 0.001) while it was increased in the LD group (decrease rGSH(L)/GSSG(L); P < 0.001). In conclusion, denervation reduces hepatic oxidative stress in BD only in contrast to the LD. The reciprocal effect of denervation depends on the state of neural activation and postulates a potential benefit of surgical denervation before organ harvesting in brain death.  相似文献   
55.
Demographic projections for hip fragility fractures indicate a rising annual incidence by virtue of a multimorbid, ageing population with more noncommunicable diseases (NCDs). NCDs are characterised by slow progression and long duration ranging from ischaemic cardiovascular disease, cerebrovascular disease, diabetes, chronic obstructive pulmonary disease to various cancers. Management of this disease burden often involves commencing patients on oral anticoagulants to reduce the risk of thromboembolic events. The use of direct oral anticoagulants (DOACs) in clinical practice has increased due to their rapid onset of action, short half-life and predictable anticoagulant effects, without the need for routine monitoring. Safe and timely surgical intervention relies on reversal of anticoagulants. However, the lack of specific evidence-based guidelines for the perioperative management of patients on DOACs with hip fractures has proved challenging; in particular, the accessibility of DOAC-specific assays, justification of the cost-benefit ratio of targeted reversal agents and indications for neuraxial anaesthesia. This has led to potentially avoidable delays in surgical intervention. Following a literature review of the pharmacokinetic and pharmacodynamics of commonly used DOACs in our region including the role of surrogate markers, we propose a systematic, evidence-based guideline to the perioperative management of hip fractures DOACs. We believe this standardised protocol can be easily replicated between hospitals. We recommend that if patients are deemed suitable for a general anaesthesia, with satisfactory renal function, optimal surgical time should be 24 h following the last ingested dose of DOAC.  相似文献   
56.

Purpose

To assess the impact of perioperative blood transfusion on overall and disease-free survival in patients undergoing curative resection for cholangiocarcinoma.

Methods

In a single-center study, 128 patients undergoing curative resection for cholangiocarcinoma between 2001 and 2010 were assessed. The median follow-up period was 19 months. Transfused and nontransfused patients were compared by Cox regression and propensity score analyses.

Results

Overall, 38 patients (29.7 %) received blood transfusions. The patient characteristics were highly biased with respect to receiving transfusions (propensity score 0.69 ± 0.22 vs. 0.11 ± 0.16, p < 0.001). In the unadjusted analysis, blood transfusion was associated with a 105 % increased risk of mortality [hazard ratio (HR) 2.05, 95 % CI 1.19–3.51, p = 0.010]. In the multivariate (HR 1.14, 95 % CI 0.52–2.48, p = 0.745) and the propensity score-adjusted Cox regression (HR 1.02, 95 % CI 0.39–2.62, p = 0.974), blood transfusion had no influence on overall survival. Similarly, in the propensity score-adjusted Cox regression (HR 0.62, 95 % CI 0.24–1.58, p = 0.295), no relevant effect of blood transfusion on disease-free survival was observed.

Conclusions

To our knowledge, this is the first propensity score-based analysis providing compelling evidence that the worse oncological outcome after curative resection for advanced cholangiocarcinoma in patients receiving perioperative blood transfusions is caused by the clinical circumstances requiring the transfusions, not by the blood transfusions themselves.  相似文献   
57.
The aim of this randomized controlled trial was to assess the effect of an occupational therapy protocol of teaching the usage of adaptive devices to older individuals in Iran who have had a total hip replacement as compared with conventional occupational therapy on functional outcomes and independence. Forty individuals diagnosed with osteoarthritis and a total hip replacement aged >60 years were randomly allocated to either control group (n = 20) or experimental (n = 20) group. Pain, disability, independence and hip muscle strength were assessed with visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis and Barthel Index and dynamometer, 2 days before and 6 weeks after the hip operation. Both groups received conventional occupational therapy, but the experimental group was additionally supervised on the use of adaptive devices. Correct use of the devices was instructed during the training session. Both groups significantly improved on all variables post‐operatively. However, the experimental group showed significantly more improvement in all dependent variables post‐operatively. No data were available on the use of the devices by the control group patients. Supervision of the utilization of the adaptive devices during regular home visits by the occupational therapist is recommended. Further research is needed to clarify which aspects of this supervision were most beneficial for the patients. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this study, a glycolipid type of biosurfactant (BS) was produced, its characteristics were evaluated and several flooding tests were conducted in a micromodel to investigate its potential for enhancing oil recovery. A rhamnolipid BS producer strain was identified as a bacterium belonging to the genus Pseudomonas aeruginosa. This BS showed good stability at temperatures of 40–121 °C, pH values of 3–10 and salinity up to 10% (w/v) NaCl which is important in Microbial Enhanced Oil Recovery (MEOR). The rhamnolipid decreased the surface tension of water from 72 to 28.1 mN m−1 with a critical micelle concentration of 120 ppm. Thin layer chromatography, FTIR spectroscopy, 1H-NMR and 13C-NMR spectroscopy revealed the glycolipid structure of the BS. Response surface methodology was applied to optimize BS production. Several micromodel flooding tests were conducted to study the capability of the produced rhamnolipid in enhanced oil recovery for the first time. An oil recovery factor of 43% was obtained at 120 ppm of BS solution whereas the recovery factor obtained for water flooding was 16%. Contact angle measurements showed that BS solutions altered the wettability of a glass surface from oil wet to a strongly water wet state. Also the results illustrated that all BS solutions were impressive in microbial enhanced oil recovery (MEOR) and using the produced BS a considerable amount of trapped oil can be extracted due to interfacial tension reduction, wettability alteration towards water wet conditions and improving the mobility ratio.

In this study, a glycolipid type of biosurfactant (BS) was produced, its characteristics were evaluated and several flooding tests were conducted in a micromodel to investigate its potential for enhancing oil recovery.  相似文献   
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