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排序方式: 共有598条查询结果,搜索用时 15 毫秒
21.
Jyoti Sharma Jonathan Matthew Brunson Nada Memon Aarif Y. Khakoo 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2012,39(6):890-893
A 41-year-old woman with metastatic melanoma was admitted to the hospital because of syncopal episodes, which had developed after the administration of an experimental chemotherapy agent that targeted Notch signaling, as part of a phase I clinical trial. Cardiac monitoring revealed recurrent episodes of polymorphic ventricular tachycardia correlating with the patient''s syncope. Investigations into the cause of the arrhythmia led to the discovery of metastatic lesions within the left ventricular myocardium. In presenting this case of polymorphic ventricular tachycardia as the antemortem clinical manifestation of metastatic melanoma involving the heart, we discuss the importance of recognizing that cardiac metastases can manifest themselves as arrhythmias in patients with malignant melanoma who are undergoing active anticancer treatment.Key words: Antineoplastic chemotherapy protocols/adverse effects, arrhythmias, cardiac/chemically induced/diagnosis/physiopathology/therapy, coronary disease/complications, heart neoplasms/pathology/secondary, melanoma/pathology, myocardium/pathology, receptors, notch/metabolism, recurrence/prevention & control, syncope/etiology, tachycardia, ventricular/chemically induced/etiologyA woman with metastatic melanoma was admitted to the hospital because of syncope and was diagnosed with episodes of polymorphic ventricular tachycardia (VT). The episodes developed after the administration of an experimental chemotherapy agent that targeted Notch signaling as part of a phase I clinical trial. The patient was found to have metastatic lesions in her myocardium. We present and discuss this case of polymorphic VT as a manifestation of cardiac metastasis in malignant melanoma in a patient who was undergoing active anticancer treatment. 相似文献
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The aim of this study was to develop a prediction equation for estimating the total widths of the mandibular permanent canines and premolars (TCPW) using the total widths of the mandibular first permanent molars and incisors (TWFMI). The sample comprised 288 mandibular dental casts of orthodontic patients (106 males and 182 females, average age 13.8 and 14.4 years, respectively). A digital vernier calliper was used to measure the mesiodistal tooth widths from the mandibular right to the left first permanent molar. An independent t-test was used to determine any gender difference and a multiple linear regression equation to predict TCPW using TWFMI. A paired t-test was used to compare the actual and predicted values of the canines and premolars. The results showed a statistically significant difference (P < 0.01) between the mesiodistal tooth widths of males and females. A moderate correlation and determination coefficient between TCPW and TWFMI was found (r = 0.64 to r = 0.67 and r(2) = 0.41 to r(2) = 0.44, respectively). There was no significant difference between actual and predicted values for males and females. The regression equations proposed are a good prediction method to determine TCPW. 相似文献
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Jai Kumar Roha Saeed Memon Izza Shahid Tehlil Rizwan Maryam Zaman Ritesh G. Menezes Sarwan Kumar Tariq Jamal Siddiqi Muhammad Shariq Usman 《Digestive and liver disease》2021,53(1):44-51
BackgroundThe efficacy of antidiabetic agents for the treatment of non-alcoholic fatty liver disease (NAFLD) remains unclear.AimTo conduct a meta-analysis to study the efficacy of pioglitazone and three novel anti-diabetic agents: glucagon-like peptide-1 (GLP-1) agonists, sodium-glucose co-transporter-2 (SGLT2) inhibitors, and dipeptidyl-peptidase-4 (DPP4) inhibitors in treating NAFLD.MethodsOnline databases were searched in May 2020 for randomized clinical trials. Results from random-effects meta-analysis are presented as weighted mean differences (WMDs) or standard mean differences (SMDs) and corresponding 95% confidence intervals (CIs).ResultsTwenty-six studies (n=946 NAFLD patients) were included. Reductions in ALT were seen with all four drugs: pioglitazone (MD -38.41, p<0.001), SGLT2 inhibitors (MD -16.17, p<0.001), GLP-1 agonists (MD -27.98, p=0.04) and DPP-4 inhibitors (MD -7.41, p<0.001). Pioglitazone (SMD -1.01; p<0.001) and GLP-1 agonists (SMD -2.53, p=0.03) also demonstrated significant improvements in liver steatosis. SGLT2 inhibitors (SMD -4.64, p=0.06) and DPP-4 (SMD -2.49, p=0.06) inhibitors trended towards reduced steatosis; however, these results were non-significant.ConclusionPioglitazone demonstrates significant improvements in transaminases and liver histology in both diabetic and non-diabetic NAFLD patients. Early evidence from diabetic NAFLD patients suggests that novel antidiabetics may lead to improvements in liver enzymes and hepatic steatosis, and this should encourage further research into possible utility of these drugs in treating NAFLD. 相似文献
27.
Ameer A. Memon Nawfal R. Hussein Véronique Y. Miendje Deyi Alain Burette John C. Atherton 《Journal of clinical microbiology》2014,52(8):2984-2989
The Helicobacter pylori virulence gene, cagA, and active forms of the vacuolating cytotoxin gene, vacA, are major determinants of pathogenesis. However, previous studies linking these factors to disease risk have often included patients using aspirin/nonsteroidal anti-inflammatory agents (NSAIDs) or acid-suppressing drugs, both of which may confound results. Also, particularly for gastric cancer (GC), controls have often been of quite different ages. Here, we performed a careful study in a “clean” Belgian population with gastric cancer cases age and sex matched to 4 controls and with a parallel duodenal ulcer (DU) group. As in other populations, there was a close association between the presence of cagA and the vacA s1 genotype. For GC, associations were found for vacA s1-positive (P = 0.01, odds ratio [OR], 9.37; 95% confidence interval [CI], 1.16 to 201.89), i1-positive (P = 0.003; OR, 12.08; 95% CI, 1.50 to 259.64), and cagA-positive status (P < 0.05; OR, infinity; 95% CI, 0.76 to infinity). For DU, associations were found with vacA s1 (P = 0.002; OR, 6.04; 95% CI, 1.52 to 27.87) and i1 (P = 0.004; OR, 4.35; 95% CI, 1.36 to 14.78) status but not with cagA status. Neither condition showed independent associations with the vacA m1 allele or with more biologically active forms of cagA with longer 3′ variable regions. In this Belgian population, the best markers of gastric cancer- and duodenal ulcer-associated strains are the vacA s1 and i1 genotypes. This fits with experimental data showing that the s and i regions are the key determinants of vacuolating cytotoxin activity. 相似文献
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Federica Cerri Luca Salvatore Danish Memon Filippo Martinelli Boneschi Marta Madaghiele Paola Brambilla Ubaldo Del Carro Carla Taveggia Nilo Riva Amelia Trimarco Ignazio D. Lopez Giancarlo Comi Stefano Pluchino Gianvito Martino Alessandro Sannino Angelo Quattrini 《Biomaterials》2014
Several bioengineering approaches have been proposed for peripheral nervous system repair, with limited results and still open questions about the underlying molecular mechanisms. We assessed the biological processes that occur after the implantation of collagen scaffold with a peculiar porous micro-structure of the wall in a rat sciatic nerve transection model compared to commercial collagen conduits and nerve crush injury using functional, histological and genome wide analyses. We demonstrated that within 60 days, our conduit had been completely substituted by a normal nerve. Gene expression analysis documented a precise sequential regulation of known genes involved in angiogenesis, Schwann cells/axons interactions and myelination, together with a selective modulation of key biological pathways for nerve morphogenesis induced by porous matrices. These data suggest that the scaffold's micro-structure profoundly influences cell behaviors and creates an instructive micro-environment to enhance nerve morphogenesis that can be exploited to improve recovery and understand the molecular differences between repair and regeneration. 相似文献
29.
Abdul Qayoom Mugheri Aneela Tahira Umair Aftab Muhammad Ishaq Abro Arfana Begum Mallah Gulam Zuhra Memon Humaira Khan Mazhar Ali Abbasi Imran Ali Halepoto Saleem Raza Chaudhry Zafar Hussain Ibupoto 《RSC advances》2019,9(59):34136
The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. In this study, we developed a facile approach to produce porous carbon from the dehydration of sucrose and use it for the preparation of nanocomposites with cobalt oxide (Co3O4). The nanocomposites were studied by the powder X-ray diffraction and scanning electron microscopy techniques, and they exhibited the cubic phase of cobalt oxide and porous structure of carbon. The nanocomposites showed significant OER activity in alkaline media, and the current densities of 10 and 20 mA cm−2 could be obtained at 1.49 and 1.51 V versus reversible hydrogen electrode (RHE), respectively. The impedance study confirms favorable OER activity on the surface of the prepared nanocomposites. The nanocomposite is cost-effective and can be capitalized in various energy storage technologies.The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. 相似文献