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101.
Mabood Qureshi Xueshu Zhang Inam ul-Haq Jim Xiang Kailash Prasad 《Experimental & Clinical Cardiology》2003,8(3):147-149
BACKGROUND:
Oxygen radicals and malondialdehyde (MDA) are tumourigenic. Homocysteine generates oxygen radicals. The possibility exists that hyperhomocysteinemia is a risk factor for cancer.OBJECTIVE:
To investigate if serum levels of homocysteine and MDA are elevated in mice with malignant tumours.METHODS:
Levels of serum homocysteine and MDA were estimated in 22 control and 22 tumour-bearing Balb/c mice.RESULTS:
Serum homocysteine levels in control and tumour-bearing mice were 3.01±0.26 μmol/L and 4.05±0.46 μmol/L, respectively. The serum levels of MDA were 6.23±0.72 nmol/mL and 11.60±1.72 nmol/mL, respectively, in control and tumour-bearing mice.CONCLUSION:
These results suggest that cancer in mice is associated with an increase in serum levels of homocysteine and the lipid peroxidation product MDA. It is, however, not known if this rise in homocysteine and MDA is due to cancer or if this rise causes cancer. 相似文献102.
Joseph C Ahn Touseef Ahmad Qureshi Amit G Singal Debiao Li Ju-Dong Yang 《World journal of hepatology》2021,13(12):2039-2051
Hepatocellular carcinoma (HCC) is among the leading causes of cancer incidence and death. Despite decades of research and development of new treatment options, the overall outcomes of patients with HCC continue to remain poor. There are areas of unmet need in risk prediction, early diagnosis, accurate pro gnostication, and individualized treatments for patients with HCC. Recent years have seen an explosive growth in the application of artificial intelligence (AI) technology in medical research, with the field of HCC being no exception. Among the various AI-based machine learning algorithms, deep learning algorithms are considered state-of-the-art techniques for handling and processing complex multimodal data ranging from routine clinical variables to high-resolution medical images. This article will provide a comprehensive review of the recently published studies that have applied deep learning for risk prediction, diagnosis, prognostication, and treatment planning for patients with HCC. 相似文献
103.
Surface treatments are normally carried out after machining. Surface treatment is a costly and time-consuming process. Hence, it makes sense to reduce the requirement of surface treatment as much as possible. Electrical Discharge Machining (EDM) is a frequently used machining process. EDM produces a recast layer on the surface of machined components. The tribological performance of this recast layer is not very well understood. The properties of the recast layer formed as a result of EDM depend upon the discharge current, electrodes and dielectrics. This work aims to study the effects of each on the tribological performance — in terms of the wear depth, friction coefficient, friction force and contact surface temperature of recast layers. Subsequent improvement in the quality of surfaces will significantly reduce the cost and time required to treat surfaces after machining. Hence, various combinations of discharge current, dielectrics and electrodes have been used to characterize and deduce their effects. The tribo-tests are performed in the boundary lubrication regime under pin-on-disc configuration to analyze sliding friction, contact surface temperature and the wear of the recast layers formed on AISI 304L. The surface morphology of the test pins has been performed by Scanning Electron Microscopy (SEM) before and after the tests. The results show that indeed it is possible to control the tribological performance of the recast layers by varying EDM parameters. This approach promises to be a useful methodology to improve the tribological performance of the layers formed after EDM and reduce the time and costs required for surface treatments post machining. 相似文献
104.
105.
Thomas J Forbes Phillip Moore Carlos A C Pedra Evan M Zahn David Nykanen Zahid Amin Swati Garekar David Teitel Shakeel A Qureshi John P Cheatham Makram R Ebeid Ziyad M Hijazi Satinder Sandhu Donald J Hagler Horst Sievert Thomas E Fagan Jeremy Ringwald Wei Du Liwen Tang David F Wax John Rhodes Troy A Johnston Thomas K Jones Daniel R Turner Robert Pass Alejandro Torres William E Hellenbrand 《Catheterization and cardiovascular interventions》2007,70(4):569-577
BACKGROUND: We report a multiinstitutional study on intermediate-term outcome of intravascular stenting for treatment of coarctation of the aorta using integrated arch imaging (IAI) techniques. METHODS AND RESULTS: Medical records of 578 patients from 17 institutions were reviewed. A total of 588 procedures were performed between May 1989 and Aug 2005. About 27% (160/588) procedures were followed up by further IAI of their aorta (MRI/CT/repeat cardiac catheterization) after initial stent procedures. Abnormal imaging studies included: the presence of dissection or aneurysm formation, stent fracture, or the presence of reobstruction within the stent (instent restenosis or significant intimal build-up within the stent). Forty-one abnormal imaging studies were reported in the intermediate follow-up at median 12 months (0.5-92 months). Smaller postintervention of the aorta (CoA) diameter and an increased persistent systolic pressure gradient were associated with encountering abnormal follow-up imaging studies. Aortic wall abnormalities included dissections (n = 5) and aneurysm (n = 13). The risk of encountering aortic wall abnormalities increased with larger percent increase in CoA diameter poststent implant, increasing balloon/coarc ratio, and performing prestent angioplasty. Stent restenosis was observed in 5/6 parts encountering stent fracture and neointimal buildup (n = 16). Small CoA diameter poststent implant and increased poststent residual pressure gradient increased the likelihood of encountering instent restenosis at intermediate follow-up. CONCLUSIONS: Abnormalities were observed at intermediate follow-up following IS placement for treatment of native and recurrent coarctation of the aorta. Not exceeding a balloon:coarctation ratio of 3.5 and avoidance of prestent angioplasty decreased the likelihood of encountering an abnormal follow-up imaging study in patients undergoing intravascular stent placement for the treatment of coarctation of the aorta. We recommend IAI for all patients undergoing IS placement for treatment of CoA. 相似文献
106.
H. Yen A. Dhana J.‐P. Okhovat A. Qureshi N. Keum E. Cho 《The British journal of dermatology》2017,177(3):696-707
Nonmelanoma skin cancer (NMSC) comprises mainly basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). The association between alcohol intake and NMSC has been inconclusive; therefore the objective of this study is to quantify the relationship between alcohol intake and NMSC using meta‐analyses. A systematic literature search of PubMed and Embase was performed on 30 October 2016. Eligible articles were case–control or cohort studies that examined alcohol intake and risk of BCC or cSCC and reported relative risks (RRs) with 95% confidence intervals (CIs). Of the 307 articles identified, 13 case–control and cohort studies were included in the systematic review, including 95 241 NMSC cases (91 942 BCC and 3299 cSCC cases). A random‐effects model was used to obtain summary RRs and 95% CIs for dose–response meta‐analyses. For every 10‐gram increase in ethanol intake per day, a positive association was found for both BCC (summary RR of 1·07; 95% CI 1·04–1·09) and cSCC (summary RR of 1·11; 95% CI 1·06–1·16). While there was evidence suggesting a nonlinear association for BCC, it may be due to the sparse data at higher alcohol intake levels. This meta‐analysis found evidence that alcohol drinking is positively associated with both BCC and cSCC risk in a dose‐dependent manner. These results should be interpreted with caution due to potential residual confounding. Nonetheless, because alcohol drinking is a prevalent and modifiable behaviour, it could serve as an important public health target to reduce the global health burden of NMSC. 相似文献
107.
Kiersten E. Norby Farhan Siddiq Malik M. Adil Saqib A. Chaudhry Adnan I. Qureshi 《Neurocritical care》2013,18(2):170-177
Background
Intracerebral hemorrhage (ICH) is an infrequent complication of intravenous recombinant tissue plasminogen activator (rt-PA) for the treatment of acute stroke. However, such ICH is an important reason for withdrawal of care because of lack of adequate data regarding long-term patient outcomes.Objective
To report the long-term outcomes in patients with post-thrombolytic ICH.Methods
We analyzed patient data from a randomized, placebo-controlled trial in patients with ischemic stroke presenting within 3 h of symptom onset. Baseline clinical characteristics and outcomes defined by modified Rankin scale (mRS) were ascertained at 3, 6, and 12 months after treatment in patients who suffered from post-thrombolytic ICH. Favorable outcome was defined by mRS of 0–3 and unfavorable outcome by mRS of 4–6 at 1 year.Results
A total of 48 patients suffered post-thrombolytic ICH in the trial. Fourteen patients had favorable outcomes and 34 patients had unfavorable outcomes. Clinical characteristics did not have an impact on patient outcomes at 12 months. Patients with unfavorable outcomes were more likely to have an National Institutes of Health Stroke Scale (NIHSS) score ≥20 at 7–10 days after treatment (64 vs. 7 %, p < 0.0009). Patients with unfavorable outcomes were more likely to have a worsening of NIHSS score of >4 points at 7–10 days from their baseline NIHSS (44 vs. 0 %, p = 0.0006).Conclusion
Approximately 30 % of patients with post-thrombolytic ICH have favorable outcomes at 1 year which does not support early withdrawal of care. Ascertainment of NIHSS score and worsening of NIHSS score at 7–10 days may be necessary for accurate prognostic stratification. 相似文献108.
Han Jo Kim Michael Steinhaus Ananth Punyala Sachin Shah Jonathan Charles Elysee Renaud Lafage Tom Riviera Guillermo Mendez Ajiri Ojadi Sharlynn Tuohy Sheeraz Qureshi Michael Urban Chad Craig Virginie Lafage Francis Lovecchio 《The spine journal》2021,21(5):753-764
BACKGROUND CONTEXTEnhanced recovery (ERAS) pathways can help hospitals maximize the incentives of bundled payment models while maintaining high-quality patient care. A key component of an enhanced recovery pathway is the ability to predictably reduce inpatient length of stay, as this is a critical component of the cost equation.PURPOSETo determine the efficacy of an enhanced recovery pathway on reducing length of stay after thoracolumbar adult deformity surgery.STUDY DESIGNSingle surgeon retrospective review of prospectively-collected data.PATIENT SAMPLEForty adult deformity patients who underwent ≥5 levels of fusion to the pelvis (two to L5) with a single surgeon before and after implementation of an ERAS pathway.METHODSThe pathway involved participation by anesthesiology, hospital medicine, and physical therapy, and was designed to achieve goals previously associated with decreased LOS (eg, EBL<1200 mL, procedure time <4.5 hours, avoidance of ICU postoperatively, and mobilization POD0-1). Patients were propensity-score matched 1:1 to a historical cohort (enhanced recovery [ER] and historical [H] cohorts), based on demographics, medical comorbidities, radiographic alignment parameters, and surgical factors. Outcomes were compared to determine the effect of the enhanced recovery pathway. Primary outcomes included LOS and 90-day complications and readmissions.RESULTSAfter matching, gender, BMI, ASA class, preoperative opioid dependence, day of surgery, sagittal alignment parameters, rate of revision surgery, three-column osteotomies, and interbody fusions were comparable between the cohorts (p>.05). In the ER cohort, there was reduced EBL (920±640 vs. 1437±555, p=.004) and no ER patient went to the ICU immediately following surgery, compared with 30% of H patients (p=.022). The ER cohort also had a greater number of patients ambulating by POD1 compared to the H cohort (100% vs. 55%, p=.010). ER patients had a shorter LOS (4.5±1.3 vs. 7.3±4.4 days, p=.010). A 90-day readmission and complications were comparable between the cohorts (p>.05).CONCLUSIONSThe creation of an ERAS pathway for patients undergoing thoracolumbar adult deformity surgery reduced length of stay without negatively affecting short-term morbidity and complications. Given the specificity of this pathway to a single surgeon and hospital, the resources and staffing changes that were instrumental in creating the pathway may not be generalizable to other centers. 相似文献
109.
Apoptosis as a form of cell death in intracerebral hemorrhage 总被引:73,自引:0,他引:73
Qureshi AI Suri MF Ostrow PT Kim SH Ali Z Shatla AA Guterman LR Hopkins LN 《Neurosurgery》2003,52(5):1041-7; discussion 1047-8
OBJECTIVE: The goals of this study were to identify and quantify the presence of programmed cell death (apoptosis) in intracerebral hemorrhage (ICH) among human subjects. Recent evidence from laboratory models suggests that cell death in the perihematoma region may involve apoptosis. METHODS: Retrospective clinical and histological analyses were performed for patients with spontaneous ICH who underwent surgical evacuation. Quantification of apoptotic cells was performed in sections obtained from the perihematoma region from 12 patients with ICH and stained with the terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling method. Necrosis was identified on the basis of morphological criteria, using hematoxylin and eosin staining. RESULTS: Evidence of apoptosis was present in surgical specimens obtained from 10 of the 12 patients. The mean number of apoptotic cells in the perihematoma region in each patient specimen was 38% (range, 0-90%). For five patients, more than one-half of the total cells observed were apoptotic. Apoptosis was observed in specimens obtained within 1 day, 2 days, and 5 days after the onset of symptoms. No terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling-positive cells were observed in specimens from the two patients with cerebellar hematomas. The mean proportion of necrotic cells in the perihematoma region in each patient specimen was 25% (range, 0-100%). There was a prominent excess of apoptotic cells, in comparison with necrotic cells, for 6 of the 12 patients who underwent hematoma evacuation. For five other patients, similar proportions of apoptotic and necrotic cells were observed. Necrosis was the predominant finding for only one patient, who underwent late surgical evacuation on Day 5. CONCLUSION: These observations suggest that apoptosis represents a prominent form of cell death associated with ICH in the perihematoma region. Further studies are required to define the mediators of apoptosis in ICH. 相似文献
110.