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11.
Thomas E. Dickerson Asad Ullah Sathvik Saineni Sandresh Sultan Srikar Sama Intisar Ghleilib Nikhil G. Patel Islam A. Elhelf Nagla Abdel Karim 《Current oncology (Toronto, Ont.)》2022,29(7):4625
Chordoma is a rare malignant neoplasm derived from notochordal tissue that primarily affects the axial skeleton. Almost 40% of patients have non-cranial chordoma metastases. The most common metastatic sites are the lungs, bones, lymph nodes, and subcutaneous tissue. We present a 52-year female with a history of sacral chordoma presenting with abdominal fullness, early satiety, and a palpable abdominal mass. Abdominal magnetic resonance imaging (MRI) revealed an isolated, highly vascularized, and multilobed liver mass in the left lateral segment. The mass was surgically removed using a clean surgical margin. A histological examination and immunohistochemical staining were consistent with a metastatic chordoma. Two years later, follow-up imaging studies showed a 6.5 × 4.0 × 2.0 cm right liver lesion with multiple lungs, chest wall, pleural, and diaphragmatic lesions. Microscopic- and immunohistochemical staining revealed a recurrent metastatic chordoma. Herein, we present a unique case of metastatic recurrent chordoma in the liver with the involvement of other sites. To the best of our knowledge, no other case of recurrent liver metastasis has been reported. 相似文献
12.
This paper investigated various aspects of replacing existing micro-resistance spot welding (micro-RSW) with micro-laser spot welding for joining Inconel 718 thin foils to thick 410 steel stack-up to allow faster, non-contact joining together with flexibility in spot positioning and removal of tip dressing required for RSW electrodes. The joint quality was evaluated based on the mechanical strength, microstructural characteristics and joint strength at elevated temperature as these joints are often used for high-temperature applications. Experimental investigations were performed using micro-RSW and micro-laser spot welding to obtain the 90° peel and lap shear specimens, each comprising four spots. The obtained strength from laser joints was significantly higher than that of micro-RSW joints due to larger weld nugget formation and interface width. The process map for obtaining good quality welds was also identified, and about a 17% reduction in joint strength was obtained when welded specimens were subjected to elevated temperature (i.e., 500 °C) in comparison with room temperature. This reduction was compensated for using the flexibility of laser welding to add two extra spots. The overall performance of the micro-laser spot welds was found to be better than the micro-RSW considering joint strength, flexibility in placing the spots and time to produce the welds. 相似文献
13.
Muhammad S. Sajid Nikhil Ladwa Lorain Kalra Kristian K. Hutson Krishna K. Singh Mazin Sayegh 《World journal of surgery》2012,36(11):2644-2653
Background
The objective of this study was to analyze systematically the randomized, controlled trials that compared single-incision laparoscopic cholecystectomy (SILC) and conventional laparoscopic cholecystectomy (CLC).Methods
The meta-analysis was conducted according to the Quality of Reporting of Meta-analysis (QUORUM) standards. The included studies were analyzed systematically using the statistical software package RevMan. The summated outcomes were expressed as the risk ratios (RR) for dichotomous variables and standardized mean differences (SMD) for continuous variables.Results
Eleven randomized trials encompassing 858 patients were retrieved from the electronic databases. In the random effects model, postoperative pain, postoperative complications, length of hospital stay, cosmesis score, conversion rate, and time to return to normal activities were statistically comparable between the two cholecystectomy techniques. SILC was associated with a longer operating time [SMD 0.71; 95?% confidence interval (CI) 0.38, 1.05; z?=?4.18; p?<?0.0001) and an increased requirement for additional port insertion (RR 6.54; 95?% CI 2.19, 19.57; z?=?3.36; p?<?0008). However, there was significant heterogeneity among the trials.Conclusions
SILC does not offer any advantage over CLC for treating benign gallbladder disorders. CLC may be used assiduously for this purpose. 相似文献14.
Rebecca M. Dodson Amin Firoozmand Omar Hyder Vania Tacher David P. Cosgrove Nikhil Bhagat Joseph M. Herman Christopher L. Wolfgang Jean-Francois H. Geschwind Ihab R. Kamel Timothy M. Pawlik 《Journal of gastrointestinal surgery》2013,17(12):2123-2132
Background
Assessment of patient performance status is often subjective. Sarcopenia—measurement of muscle wasting—may be a more objective means to assess performance status and therefore mortality risk following intra-arterial therapy (IAT).Methods
Total psoas area (TPA) was measured on cross-sectional imaging in 216 patients undergoing IAT of hepatic malignancies between 2002 and 2012. Sarcopenia was defined as TPA in the lowest sex-specific quartile. Impact of sarcopenia was assessed relative to other clinicopathological factors.Results
Indications for IAT included hepatocellular carcinoma (51 %), intrahepatic cholangiocarcinoma (13 %), colorectal liver metastasis (7 %), or other metastatic disease (30 %). Median TPA among men (568 mm2/m2) was greater than women (413 mm2/m2). IAT involved conventional chemoembolization (54 %), drug-eluting beads (40 %), or yttrium-90 (6 %). Median tumor size was 5.8 cm; most patients had multiple lesions (74 %). Ninety-day mortality was 9.3 %; 3-year survival was 39 %. Factors associated with risk of death were tumor size (HR?=?1.84) and Child's score (HR?=?2.15) (all P?<?0.05). On multivariate analysis, sarcopenia remained independently associated with increased risk of death (lowest vs. highest TPA quartile, HR?=?1.84; P?=?0.04). Sarcopenic patients had a 3-year survival of 28 vs. 44 % for non-sarcopenic patients.Conclusions
Sarcopenia was an independent predictor of mortality following IAT with sarcopenic patients having a twofold increased risk of death. Sarcopenia is an objective measure of frailty that can help clinical decision-making regarding IAT for hepatic malignancies. 相似文献15.
16.
Marshall Colin Enzerra Michael Rahnemai-Azar Amir Ata Ramaiya Nikhil H. 《Abdominal imaging》2019,44(3):1083-1090
Abdominal Radiology - Serum tumor markers (STMs) play a critical role in the diagnosis, staging and follow-up of both seminomatous and nonseminomatous testicular germ cell neoplasms. Levels of... 相似文献
17.
Farshid Amirabdollahian Salvatore Livatino Behrad Vahedi Radhika Gudipati Patrick Sheen Shan Gawrie-Mohan Nikhil Vasdev 《Journal of robotic surgery》2018,12(1):11-25
With the successful uptake and inclusion of robotic systems in minimally invasive surgery and with the increasing application of robotic surgery (RS) in numerous surgical specialities worldwide, there is now a need to develop and enhance the technology further. One such improvement is the implementation and amalgamation of haptic feedback technology into RS which will permit the operating surgeon on the console to receive haptic information on the type of tissue being operated on. The main advantage of using this is to allow the operating surgeon to feel and control the amount of force applied to different tissues during surgery thus minimising the risk of tissue damage due to both the direct and indirect effects of excessive tissue force or tension being applied during RS. We performed a two-rater systematic review to identify the latest developments and potential avenues of improving technology in the application and implementation of haptic feedback technology to the operating surgeon on the console during RS. This review provides a summary of technological enhancements in RS, considering different stages of work, from proof of concept to cadaver tissue testing, surgery in animals, and finally real implementation in surgical practice. We identify that at the time of this review, while there is a unanimous agreement regarding need for haptic and tactile feedback, there are no solutions or products available that address this need. There is a scope and need for new developments in haptic augmentation for robot-mediated surgery with the aim of improving patient care and robotic surgical technology further. 相似文献
18.
In up to 50 % of patients undergoing continuous flow, axial pump, left-ventricular and assist device (LVAD) placement, concomitant procedures are performed. The underlying lesions have a broad spectrum of severity, complexity, and impact on clinical outcomes. This review describes the concomitant lesions often encountered with LVAD implantation and clinical relevance of their repair. 相似文献
19.
Tai YT Dillon M Song W Leiba M Li XF Burger P Lee AI Podar K Hideshima T Rice AG van Abbema A Jesaitis L Caras I Law D Weller E Xie W Richardson P Munshi NC Mathiot C Avet-Loiseau H Afar DE Anderson KC 《Blood》2008,112(4):1329-1337
Currently, no approved monoclonal antibody (mAb) therapies exist for human multiple myeloma (MM). Here we characterized cell surface CS1 as a novel MM antigen and further investigated the potential therapeutic utility of HuLuc63, a humanized anti-CS1 mAb, for treating human MM. CS1 mRNA and protein was highly expressed in CD138-purified primary tumor cells from the majority of MM patients (more than 97%) with low levels of circulating CS1 detectable in MM patient sera, but not in healthy donors. CS1 was expressed at adhesion-promoting uropod membranes of polarized MM cells, and short interfering RNA (siRNA) targeted to CS1 inhibited MM cell adhesion to bone marrow stromal cells (BMSCs). HuLuc63 inhibited MM cell binding to BMSCs and induced antibody-dependent cellular cytotoxicity (ADCC) against MM cells in dose-dependent and CS1-specific manners. HuLuc63 triggered autologous ADCC against primary MM cells resistant to conventional or novel therapies, including bortezomib and HSP90 inhibitor; and pretreatment with conventional or novel anti-MM drugs markedly enhanced HuLuc63-induced MM cell lysis. Administration of HuLuc63 significantly induces tumor regression in multiple xenograft models of human MM. These results thus define the functional significance of CS1 in MM and provide the preclinical rationale for testing HuLuc63 in clinical trials, either alone or in combination. 相似文献
20.