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排序方式: 共有911条查询结果,搜索用时 15 毫秒
1.
Mahwash Kassi Venkateshwar Polsani Robert C. Schutt Solomon Wong Faisal Nabi Michael J. Reardon Dipan J. Shah 《The Journal of thoracic and cardiovascular surgery》2019,157(5):1912-1922.e2
Background
The purpose of this analysis is to describe the differences in cardiac magnetic resonance characteristics between benign and malignant tumors, which would be helpful for surgical planning.Methods
This was a prospective cohort study of 130 patients who underwent cardiac magnetic resonance imaging for evaluation of a suspected cardiac mass. After excluding thrombi and tumors without definitive diagnosis, 66 tumors were evaluated for morphologic features and tissue composition.Results
Of the 66 patients, 39 (59.0%) had malignant tumors and 27 (41.0%) had benign tumors. Patients with malignant tumors were younger when compared with those with benign tumors (age 51 years [42.8-60.0] vs 65 years [60.0-71.0] median). Malignant tumors more often demonstrated tumor invasion (69% vs 0% P < .001) and were more often associated with pericardial effusion (41% vs 7.4% P = .004). Presence of first-pass perfusion (100% vs 33% P < .001) and late gadolinium enhancement (100% vs 59.2%, P < .001) were significantly higher in malignant tumors. In logistic regression modeling, tumor invasion (P < .001) and first-pass perfusion (P < .001) were independently associated with malignancy. Furthermore, using classification and regression tree analysis, we developed a decision tree algorithm to help differentiate benign from malignant tumors (diagnostic accuracy ~90%). The algorithm-weighted cost of misclassifying a malignant tumor as benign was twice that of classifying a benign tumor as malignant.Conclusions
Our study demonstrates that cardiac magnetic resonance imaging is a useful noninvasive method for differentiating malignant from benign cardiac tumors. Tumor size, invasion, and first-pass perfusion were useful imaging characteristics in differentiating benign from malignant tumors. 相似文献2.
Isaac Samuel M.D. Mark A. Yorek Ph.D. Asgar Zaheer Ph.D. Rory A. Fisher Ph.D. 《Journal of gastrointestinal surgery》2006,10(7):950-959
Using a unique surgical model (the donor rat model), we showed previously that duodenal replacement of bile-pancreatic juice,
obtained fresh from a donor rat, ameliorates ligation-induced acute pancreatitis. We hypothesize that bile-pancreatic juice
exclusion from gut exacerbates Akt/nuclear factor-kB (NF-kB) pathway activation and induces chemokine production in ligation-induced acute pancreatitis. We compared rats with bile-pancreatic
duct ligation to those with duodenal bile-pancreatic juice replacement fresh from a donor rat beginning immediately before
duct ligation. Sham control rats had ducts dissected but not ligated. Rats were killed 1 or 3 hours after operation (n=7/group).
Akt activation (immunoblotting, immune-complex kinase assay, and ELISA), inhibitory protein I-kB (I-kB) activation (immunoblotting), and production of chemokines MCP-1 and RANTES (ELISA) were measured in pancreatic homogenates.
NF-kB was quantitated in nuclear fractions using electrophoretic mobility shift assay. Duct ligation produced significant increases
in pancreatic Akt, IkB, and NF-kB activation and production of MCP-1 and RANTES. Activation of the Akt/NF-kB pathway and increased MCP-1 and RANTES production in response to duct ligation were significantly reduced by bile-pancreatic
juice replacement (ANOVA, P<0.05). Bile-pancreatic juice exclusion stimulates Akt/NF-kB pathway activation and increases chemokine production in ligation-induced acute pancreatitis.
Presented at the annual meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 16, 2005 (poster). 相似文献
3.
H M al-Freihi A al-Hamdan A al-Qurain Y M al-Gindan E M Ibrahim G al-Ghassab H I Nabi 《Tropical gastroenterology》1991,12(2):77-82
The efficacy and safety of a single nocturnal dose of famotidine (40 mg) was evaluated in 30 consecutive patients of duodenal ulcer (DU). Three patients were lost for follow-up and therefore were excluded. The mean age of remaining 27 patients was 34.3 (+/- 9.9) years and male to female ratio was 8:1. The mean size of the DU was 1.21 (+/- 0.79) cm. After a 4-week therapy all patients showed significant improvement and repeat endoscopy in 24 out of 27 patients (89%, 95% confidence interval; 78% to 100%) showed healed ulcer. Clinical assessment of pain relief at 4-week showed significant drop in the mean score of baseline daytime (from 1.85 to 0.13) and baseline nocturnal pain (from 1.70 to 0.10) (p less than 0.0001 and less than 0.0001, respectively). Also shown was the significant decrease in the mean gastrointestinal symptoms score from 5.89 at baseline to only 0.89 at 4-week (p less than 0.0001). Despite that all those who failed to show ulcer healing at 4-week were smokers, logistic regression analysis could not identify smoking or any other risk factors as adverse predictors of ulcer healing. None of the patients experienced significant side effects or adverse reactions. We conclude, that a single nocturnal dose of famotidine is a practical, highly effective and safe approach for the management of DU. 相似文献
4.
Tumor autocrine motility factor (AMF) is a cytokine which stimulates both random and directed cell migration by self-producing cells. AMF has been detected in and purified from serum-free conditioned medium of murine B16-F1 melanoma cells. Under nonreducing conditions AMF migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a single band of Mr 55,000, whereas under reducing conditions it migrates as a single polypeptide of Mr 64,000. Two-dimensional polyacrylamide gel electrophoresis of the purified AMF resolved two polypeptides with isoelectric points of 6.35 (major) and 6.4 (minor). No carbohydrate side chains were detected in the B16-F1 AMF. Purified AMF stimulated B16-F1 cell migration in a dose-dependent fashion and bound directly in a protein-protein-binding assay to the AMF receptor, a cell surface glycoprotein of Mr 78,000 [glycoprotein (gp) 78]. The involvement of gp78 in AMF-stimulated function was demonstrated by motility assays. These results suggest that AMF is the natural ligand for the gp78-AMF receptor. 相似文献
5.
Radiolabeled monoclonal antibody imaging (immunoscintigraphy) of colorectal cancers: current status and future perspectives. 总被引:2,自引:0,他引:2
Over the past two decades, the role of radiolabeled monoclonal antibodies has been steadily growing in clinical practice, particularly for staging and locating a variety of neoplasms. This is due largely to the availability of these products in pharmaceutical quantities as well as the relatively low incidence of adverse reactions following the intravenous administration of antibodies to patients. One particular area of oncology where radiolabeled monoclonal antibodies are most likely to play an extremely important clinical role is in the evaluation of patients with colon and rectal carcinomas. In this report, we review the current utilization of tumor-associated monoclonal antibodies in the preoperative as well as postoperative screening of patients with colorectal carcinoma. 相似文献
6.
118 multibacillary leprosy patients with differential manifestations were studied for the antigens they expressed at MHC loci to investigate the role of human leukocyte antigens in the differential response to the same causative agent. While the lepromatous leprosy (LL) patients showed a significant increase of Bw60, DR2, DRw8 and DQw1, borderline lepromatous (BL) patients had Bw52, DR9 and DQw7 significantly more often as compared to the normal controls. A comparison of LL, BL and mid-borderline (BB) patients showed a significantly higher frequency of Bw60 in LL patients as compared to the BL. However, Bw52, Bw53, DR9 and DQw7 were found significantly more often in the BL patients as compared to the LL patients but the difference failed to reach significance after pc. A comparison of HLA antigens in BB patients with those of either the LL or BL patients did not show any significant differences. 相似文献
7.
8.
Rajni Rani S. A. Zaheer N. R. Suresh R. Walia S. K. Parida A. Mukherjee Rama Mukherjee G. P. Talwar 《Journal of clinical immunology》1992,12(1):50-55
Leprosy patients undergoing phase II trials in two hospitals of New Delhi, India, were HLA typed to see the association of HLA with differential responsiveness toMycobacterium w vaccine. The vaccine comprises an atypical, nonpathogenic mycobacterium,Mycobacterium w, which has cross-reactive antigens withM. leprae. Multibacillary patients who are lepromin negative are vaccinated at an interval of 3 months. Considerable improvement is evident in the patients in terms of a decline in bacterial indices and histopathological and immunological upgrading. But all the patients do not respond to the vaccine in the same manner; some are slow responders, while others are good responders. HLA-A28 and DQw3 (DQw8+9) were found to be associated with slow responsiveness, while DQw1 and DQw7 were found to be associated with a more rapid responsiveness to theM. w vaccine. However, these associations were not significant afterP correction for the number of antigens tested for each locus except for HLA-DQw3 (DQw8 and DQw9) and DQw7. DQw7, a new defined split of HLA-DQw3, seems to be associated with the responsiveness toM. w vaccine. 相似文献
9.
10.
We report a case of a 40-year-old man who had presented with a spontaneous suprapubic urinary leak from a well-healed suprapubic cystostomy tract scar, 20 years following a successful scrotal tube substitution urethroplasty done for a post-traumatic urethral stricture. Preoperative contrast studies suggested a recurrent bulbomembranous urethral stricture. Excision biopsy of the suprapubic fistulous tract revealed scar cancer infiltrating the bladder wall. Of 3 similar cases reported in the past, only 1 had bladder involvement. Ours is the second such case with bladder involvement. 相似文献