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101.
This is the 7th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at http://www.aseronline.org/curriculum/toc.htm. 相似文献
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Five new isostructural lanthanide–organic complexes, [Ln2O2(OH)(HQXD)(H2QXD)2]·H2O (Ln = Eu 1, Tb 2, Sm 3 Dy 4 and Gd 5; H2QXD = quinoxaline-2,3(1H,4H)-dione), have been synthesized under hydrothermal conditions. These complexes are characterized by powder X-ray diffraction (PXRD), infrared spectroscopy (IR), elemental analysis (EA), thermogravimetric-differential thermal analysis (TG-DTA) and photo-luminescent spectroscopy. Single crystal X-ray diffraction analysis of complex 1 revealed that the structure featured in 1D chiral “Eu2O3” chains surrounded by coordinating organic ligands. These chains are interconnected via hydrogen bonding and offset π⋯π stacking interactions of the ligands to form the 3D supramolecular frameworks. The photo-luminescence studies for complexes 1–5 disclosed that the ligand (H2QXD) showed an antenna effect to transfer energy toward the lanthanide cations. The energy transfer mechanism investigations show that the energy transition from the triplet energy level (3ππ*) of ligand H2QXD to the Tb3+ cation is more effective than to the Eu3+, Sm3+ and Dy3+ ions; therefore it has been selected as a representative to examine the potential for sensing small molecules. Complex 2′, which was obtained by the heating treatment of 2 at 150 °C, displayed a high luminescence sensitivity towards small solvent molecules. Tertiary butanol (t-butanol) was found to be an excellent sensitizer, while tetrahydrofuran (THF) was a highly quenching species. Complex 2′ could regain a higher photo-luminescence intensity after treating for 5 cycles with t-butanol, revealing a prospect for reusability.A series of isostructural lanthanide–quinoxaline-2,3(1H,4H)-dione containing 1D chiral chains shows high sensing effect toward the small solvent molecules, in which tertiary butanol was an excellent sensitizer, while tetrahydrofuran was a highly quenching species. 相似文献
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A variety of different signaling pathways are necessary for development and maintenance of the human auditory system. Normal hearing allows for the detection of soft sounds within the frequency range of 20 to 20 000 Hz, but more importantly to perceive the human voice frequency band of 250 to 6000 Hz. Loss of hearing is common, and is a clinically heterogeneous disorder that can be caused by environmental factors such as exposure to loud noise, infections and ototoxic drugs. In addition, variants of hundreds of genes have been reported to disrupt processes required for hearing. Noncoding regulatory variants and variants of additional genes necessary for hearing remain to be discovered as many individuals with inherited deafness are without a genetic diagnosis, despite the advent of whole exome sequencing. Here, we discuss in detail some of these deafness-causing variants of genes encoding a ligand or its receptor. Spotlighted in this review are three growth factor-receptor-pairs EDN3/EDNRB, HGF/MET and JAG/NOTCH, which individually are necessary for normal hearing. We also offer our perspective on unanswered questions, future challenges and potential opportunities for treatments emerging from molecular genetic and mechanistic studies of deafness due to these causes. 相似文献
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Ritu?GuptaEmail authorView authors OrcID profile Gurvinder?Kaur Lalit?Kumar Lata?Rani Nitin?Mathur Atul?Sharma Meetu?Dahiya Varun?Shekhar Sadaf?Khan Anjali?Mookerjee Om?Dutt?Sharma 《Annals of hematology》2018,97(12):2447-2454
The recently introduced Revised International Staging System (R-ISS) for multiple myeloma (MM) integrates albumin, β2 microglobulin, lactate dehydrogenase (LDH) with high-risk cytogenetic aberrations (CA), i.e., t(4;14) and t(14;16) and del17p using fluorescent in situ hybridization (FISH). We evaluated utility of nucleic acid-based tests of multiplex ligation-based probe amplification (MLPA) and quantitative real-time polymerase chain reaction (qRT-PCR) to define the CA and the R-ISS categories as per this approach were evaluated for their ability to predict outcome in terms of response, progression-free (PFS), and overall survival (OS). In this study (n?=?180), 17 (9.4%), 118 (65.6%), and 45 (25%) patients were assigned to R-ISS1, R-ISS2, and R-ISS3 categories with statistically significant differences in median PFS (p?=?0.02) and OS (p?<?0.001).On univariate analysis, serum creatinine, LDH, 17p deletion, chromosome 1q gain, and response after first induction therapy were associated with statistically significant differences (p?<?0.05) in PFS and in addition, age>?65 years and use of triplet therapy with OS. On multivariate analysis, only serum creatinine, LDH, and response after first induction therapy retained significance for predicting PFS and in addition, use of triplet therapy retained significance for the OS. The proposed nucleic acid-based algorithm using qRT-PCR and MLPA for R-ISS is resource-effective in terms of small quantities of sample required; feasibility of batch processing and reduced overall cost for the total number of regions evaluated and retained the prognostic significance of R-ISS, making it suitable for clinical practice for molecular characterization of MM. 相似文献
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Kabir Sadaf Farrokhvar Leily Russell Michael W. Forman Alex Kamali Behrooz 《Zeitschrift fur Gesundheitswissenschaften》2022,30(6):1513-1522
Journal of Public Health - The role of socioeconomic status (SES) of patients in health care outcomes has been investigated in many health care systems. The health care literature suggests that... 相似文献
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Raees Tonse Tejpal Gupta Sridhar Epari Jayant Goda Shastri Mamta Gurav Nazia Bano Rakesh Jalali 《Journal of neuro-oncology》2018,136(2):343-350
We present outcomes of pleomorphic xanthoastrocytoma (PXA) and correlate the impact of clinical, pathologic and molecular markers. Between 2006 and 2016, 37 patients with histologically verified PXA form the study cohort. All underwent maximal safe resection; those who had good resection and young age were observed. Adjuvant radiotherapy was given in patients with some atypical features such as high MIB-1 index (>?5%), residual disease or at recurrence. Patients with anaplastic PXA were administered adjuvant radiotherapy and systemic therapy. Median age at diagnosis was 20 years (range 4–45). At median follow-up of 33 months, 3-year and 5-year overall survival (OS) was 80.2 and 74% respectively. Patients who underwent GTR (23 cases, 62%) had significantly better 3-year PFS of 85.6% compared to 32.3% (p?=?0.001) achieved with STR (13 cases, 35%). PFS was significantly superior in PXA grade II as compared to anaplastic PXA group (3-year estimates 80.2 vs. 32%; p?=?0.007). 13 out of 27 patients where BRAFV600E testing was successful showed a mutation (48%). 3-year PFS and OS survival in BRAFV600E mutated patients was 51.9 and 76.9% compared to 73 and 75% in BRAFV600E non-mutated patients, respectively. No patient had IDH1 mutation. This data may provide valuable insights and act as a benchmark for future studies. 相似文献
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Nazia Darvesh Jai K. Das Tyler Vaivada Michelle F. Gaffey Kumanan Rasanathan Zulfiqar A. Bhutta for the Social Determinants of Health Study Team 《BMC public health》2017,17(4):776