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991.
Sentinel lymph node dissection (SLND) is a standard axillary staging technique in breast cancer and intraoperative sentinel lymph node (SLN) assessment is important for decision‐making regarding additional treatment and reconstruction. This study was undertaken to investigate clinicopathologic factors impacting the accuracy of intraoperative SLN evaluation. Records of patients with clinically node‐negative, invasive breast cancer who underwent SLND with frozen section intraoperative pathologic evaluation from 2004 to 2007 were reviewed. Intraoperative SLN assessment results were compared to final pathology. Patients with positive SLNs that were initially reported as negative during intraoperative assessment were considered false negative (FN) events. Primary tumor histology, grade, receptor status, size, lymphovascular invasion (LVI), multifocality, neoadjuvant chemotherapy or hormonal therapy, number of SLNs retrieved, and SLN metastasis size were evaluated. The study included 681 patients, of whom 262 (38%) received neoadjuvant therapy. There were 183 (27%) patients who had a positive SLN on final pathology, of whom 60 (33%) had FN events. On univariate analysis, lobular histology, favorable histology, absence of LVI and micrometastasis were associated with a higher FN rate. On multivariate analysis, favorable and lobular histology and micrometastasis were independent predictors of FN events whereas LVI and receipt of neoadjuvant therapy were not statistically significant predictors. The accuracy of intraoperative SLN evaluation for breast cancer is affected by primary tumor histology and size of the SLN metastasis. There was no significant association between neoadjuvant therapy and the FN rate by intraoperative assessment. This information may be helpful in counseling patients about their risk for a FN intraoperative SLN assessment and for planning for immediate breast reconstruction in patients undergoing mastectomy.  相似文献   
992.
Introduction With more than 10 million of daily users, e-cigarettes encountered a great success. But in the past few years, the number of medical reports of injuries caused by the explosion of e-cigarettes has significantly increased. This article aims at reporting our series and reviewing the literature to propose a new classification based on the mechanisms of injuries related to e-cigarettes that can guide non-specialists and specialists in the management of these patients.Method We performed a retrospective review of our institutional burn database from June 2016 to July 2017 for injuries caused by or in the context of using an e-cigarette. The patients’ demographics (age, gender), burn injury mechanisms, depth, localization, surface and interventions were described.Results Ten patients suffered from burns related to the use of e-cigarettes. The burns were located at the thigh (80%) and the hand (50%) with a mean surface of 3% of TBSA. Four different mechanisms could be described: Type A: thermal burns with flames due to the phenomenon of “thermal runaway”, Type B: blasts lesions secondary to the explosion, Type C: chemical alkali burns caused by spreading of the electrolyte solution and Type D: thermal burns without flames due to overheating. These different mechanisms suggest specific surgical and non-surgical management.Conclusion Management of injuries sustained from e-cigarettes’ explosions should be approached from the standpoint of mechanisms. Different mechanisms could be associated and should be considered in specific management.  相似文献   
993.

Background

A growing body of published research on tranexamic acid (TXA) suggests that it is effective in reducing blood loss and the risk for transfusion in total knee arthroplasty (TKA). The purpose of this network meta-analysis was to evaluate TXA in primary TKA as the basis for the efficacy recommendations of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Medicine on the use of TXA in primary total joint arthroplasty.

Methods

We searched Ovid MEDLINE, Embase, Cochrane Reviews, Scopus, and Web of Science databases for publications before July 2017 on TXA in primary total joint arthroplasty. All included studies underwent qualitative and quantitative homogeneity testing. Direct and indirect comparisons were performed as a network meta-analysis, and results were tested for consistency.

Results

After critical appraisal of the available 2113 publications, 67 articles were identified as representing the best available evidence. Topical, intravenous (IV), and oral TXA formulations were all superior to placebo in terms of decreasing blood loss and risk of transfusion, while no formulation was clearly superior. Use of repeat IV and oral TXA dosing and higher doses of IV and topical TXA did not significantly reduce blood loss or risk of transfusion. Preincision administration of IV TXA had inconsistent findings with a reduced risk of transfusion but no effect on volume of blood loss.

Conclusions

Strong evidence supports the efficacy of TXA to decrease blood loss and the risk of transfusion after primary TKA. No TXA formulation, dosage, or number of doses provided clearly improved blood-sparing properties for TKA. Moderate evidence supports preincision administration of IV TXA to improve efficacy.  相似文献   
994.
In the case of coexisting abdominal aortic aneurysm (AAA) and liver/renal failure, the controversial issue is the timing of the AAA repair and the transplantation of the affected organs. The question is whether to repair the AAA first and perform the double transplantation at a later time, or to perform all three procedures in the same operative session. This patient was affected by hepatic/renal failure and had also developed AAA. We describe the operative strategies utilized to perform the cadaver donor and recipient operations in this setting. In our patient, a combined liver/kidney transplantation with simultaneous aneurysm repair using arterial allografts was successfully performed. In a patient affected by end-stage liver, kidney, and aneurysmatic disease, a simultaneous liver/kidney transplant and AAA repair may represent the safest and most efficient treatment solution.  相似文献   
995.
Chordomas are rare bone tumors and treatment is commonly based on a combination of surgery and radiotherapy. There is no standard chemotherapy treatment for chordoma. The aim of this study was to determine the expression of cyclin‐dependent kinase 4 (CDK4) in chordoma and its therapeutic implications. We evaluated CDK4 expression both in chordoma cell lines and in chordoma tissues. Also, we investigated the functional roles of CDK4 in chordoma cell growth and proliferation. Furthermore, the therapeutic implications of targeting CDK4 in chordoma were evaluated. We found CDK4 highly expressed in chordoma cell lines and in a majority (97.7%) of chordoma tissues. Higher CDK4 expression correlated with metastasis and recurrence of chordoma. Treatment of chordoma cells using CDK4 inhibitor palbociclib could efficiently inhibit chordoma cells growth and proliferation. These data demonstrate that targeting CDK4 may be useful as a novel strategy in the treatment of chordoma. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1581–1589, 2018.
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996.
997.
998.
Little has been published on the outcomes of polyethylene liner exchanges for wear or osteolysis. We assessed 24 patients from our clinic who had an isolated polyethylene liner exchange for wear or osteolysis with retention of the acetabular shell and femoral stem. At a mean 56-month follow-up time, 6 hips (25%) had dislocated. Of these, 2 underwent repeat surgery for recurrent dislocation; 1 had 3 dislocations; 1 had 2 dislocations; and 2 had single dislocations. Seventeen of the remaining patients answered our questionnaire: 13 recovered faster from the polyethylene liner exchange than from the primary arthroplasty; 4 believed that their hips were not as stable, 4 believed the hip did not function as well; and 1 underwent revision for cup loosening. We conclude that polyethylene liner exchanges, with or without femoral head exchange for wear or osteolysis, are associated with a high risk of dislocation and possible decrease in function.  相似文献   
999.
Abstract: Our research goal is to report on method of breast cancer detection among young women from a prospective cohort study of primary breast cancer patients, aged 20–49 years, 1990–2008 (n = 2579). Clinical presentation characteristics including race, TNM stage, first degree relative family history, histologic type and method of detection by patient (PtD), physician (PhysD), or mammography (MamD) were chart abstracted. Forward conditional stepwise regression was used to for association with detection method and Kaplan‐Meier for relapse free survival (RFS) analysis. Among 20‐ to 39‐year olds (n = 602) no change in detection method occurred over time with 12% MamD, 7% PhysD, and 81% PtD. Among 40‐ to 49‐year olds, MamD BC increased over time (28% to 58%) and PtD BC decreased (63–36%) (Pearson X2= 72.72, p < .001). Among 20–39/40‐ to 49‐year old MamD cases 31%/32% were stage 0 versus 2%/6% of the PhysD/PtD cases. In two separate conditional logistic regression models, older age at diagnosis and first degree relative BC history were associated with MamD BC for 20‐ to 39‐ and 40‐ to 49‐year olds. Five‐year MamD BC RFS was superior for both age groups (20–39: 94%, 40–49: 94%) compared to PtD BC rates (20–39: 80%, p = .016; 40–49: 88%, p < .001). For PtD BC 20‐ to 39‐year olds had worse RFS (5 year 80%, 10 year 75%) than 40‐ to 49‐year olds (5 year 88%, 10 year 82%) (p = .002) but RFS was equivalent for MamD cases by age. The majority of breast cancers among women 20–49 years were patient detected and mammography detection occurred rarely among youngest women. Lower stage and superior survival among MamD patients support mammography for detecting disease in high risk women aged 30–39 years and 40–49 years.  相似文献   
1000.
In vitro activity of ciprofloxacin against 27 strains of enterococci was inoculum dependent. Using inocula of 10(5) to 10(6) or 10(7) to 10(8) CFU of enterococci per ml, the MICs for 50 and 90% of strains tested increased from 1 to greater than or equal to 128 micrograms of ciprofloxacin per ml with the higher inoculum compared with the lower inoculum. The MBC for 50% of strains tested increased from 2 to greater than 128 micrograms/ml and the MBC for 90% of strains tested increased from 8 to greater than 128 micrograms of ciprofloxacin per ml with the lower and higher inocula, respectively. The combination of penicillin-gentamicin was more effective in vitro than the combination of ciprofloxacin-gentamicin against the low or high inoculum of enterococci. Using two strains of enterococci, we studied the efficacy of ciprofloxacin in the treatment of enterococcal experimental endocarditis in rabbits. Ciprofloxacin used alone or combined with gentamicin was significantly less effective (P less than 0.01) than procaine penicillin alone or procaine penicillin combined with gentamicin for the treatment of enterococcal experimental endocarditis. The combination of ciprofloxacin-procaine penicillin was not a more effective therapy than procaine penicillin alone.  相似文献   
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