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1.
Objectives. We sought to examine the relation between regional changes in intramyocardial function and global left ventricular (LV) remodeling in the first 8 weeks after reperfused first anterior myocardial infarction (MI).

Background. Because of limitations in imaging methods used to date, this relation has not been thoroughly evaluated.

Methods. We studied 26 patients (21 men, 5 women; mean age 51 years) by magnetic resonance imaging (MRI) on day 5 ± 2 (mean ± SD) and week 8 ± 1 after their first anterior MI. All patients had single-vessel left anterior descending coronary artery disease and although they had received reperfusion therapy, all had regional LV dysfunction and an initial ejection fraction (EF) ≤50%. Short-axis magnetic resonance tagging was performed spanning the LV. Percent intramyocardial circumferential shortening (%S) on a topographic basis, LV mass index, LV end-diastolic volume index (LVEDVI), LV end-systolic volume index and LV ejection fraction (LVEF) were measured.

Results. Left ventricular mass index tended to decrease, whereas the LVEDVI increased from 82 ± 24 to 96 ± 27 ml/m2 (p = 0.002). Left ventricular end-systolic volume index remained unchanged, whereas LVEF increased from 39 ± 12% to 45 ± 14% (p = 0.002). Apical %S improved from 9 ± 6% to 13 ± 5% (p < 0.0001), as it did in the midanterior (6 ± 6% to 10 ± 7%, p < 0.02) and midseptal regions (8 ± 7% to 12 ± 6%, p < 0.02). Early dysfunction in remote midinferior and basal lateral regions resolved by 8 weeks. By multivariate analysis, the only significant predictor of an increase in LVEDVI over the study period was peak creatine kinase (p = 0.04).

Conclusions. In the first 8 weeks after a large, reperfused anterior MI, %S improved in the apex, midanterior and midseptal regions and normalized in remote noninfarct-related regions, but LV end-diastolic volumes also increased. This increased LVEDVI correlated with infarct size by peak creatine kinase and was not related to changes in global and regional LV function.  相似文献   

2.
In order to find out correlations between the structure of an external donor and the obtained polymer, the effects of different external donors on the activity and stereospecificity of the MgCl2/TiCl4 catalytic system in the bulk polymerization of 4-methyl-1-pentene (4MP) were carefully studied. Different silane compounds of the structure RnSi(OR')4-n (where: n = 1–3, R = alkyl/phenyl, R = alkyl) and Al(i-Bu)3 (TIBA) were used as external donors and cocatalyst, respectively. The effect of the donor/TIBA mole ratio on the activity and stereospecificity of the catalytic system was studied. Some major effects were observed for the three different external donors, namely, Me3Si(OMe), Me2Si(OMe)2, and Me3Si(OBu)3, in the 4MP polymerization process. It was observed that the effect of the external silane donor on the polymerization strongly depends upon the size of the alkoxy and hydrocarbon (alkyl/phenyl) groups which are attached to the silicon atom. A selective deactivation of the non-stereospecific centers, as well as a transformation of the non-stereospecific into isospecific centers, is assumed to occur. On the basis of the obtained results and literature data available for the propene polymerization, the concept of structural conformity between the ligand-surrounded active center and the monomer molecule was carried forward.  相似文献   
3.
A modified technique for handsewn anastomosis after abdominoperineal pull-through resection is described. The technique is a continuous locked modification of the Gambee suture. Simplicity, rapidity, reliability, and firmness are the advantages of this technique.  相似文献   
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5.
This report describes our experience with a 5-year-old girl who had an extremely rare presentation of a right atrial aneurysm and associated Wolff-Parkinson-White syndrome. Before being referred to our department, she underwent an ineffective radiofrequency ablation for repeated episodes of paroxysmal supraventricular tachycardia that were causing dizziness, palpitations, and chest discomfort. We resected the aneurysm with good results; she was doing well and was in normal sinus rhythm at the time of her 1-year follow-up visit.  相似文献   
6.
Introduction and ObjectiveUnlike clear cell renal cell carcinoma (CCRCC), collecting duct carcinoma (CDC) and renal medullary carcinoma (RMC) are rare tumors that progress rapidly and appear resistant to current systemic therapies. We queried comprehensive genomic profiling to uncover opportunities for targeted therapy and immunotherapy.Material and MethodsDNA was extracted from 40 microns of formalin-fixed, paraffin-embedded specimen from relapsed, mCDC (n = 46), mRMC (n = 24), and refractory and metastatic (m) mCCRCC (n = 626). Comprehensive genomic profiling was performed, and Tumor mutational burden (TMB) and microsatellite instability (MSI) were calculated. We analyzed all classes of genomic alterations.ResultsmCDC had 1.7 versus 2.7 genomic alterations/tumor in mCCRCC ( = 0.04). Mutations in VHL (P < 0.0001) and TSC1 (P = 0.04) were more frequent in mCCRCC. SMARCB1 (P < 0.0001), NF2 (P = 0.0007), RB1 (P = 0.02) and RET (P = 0.0003) alterations were more frequent in mCDC versus mCCRCC. No VHL alterations in mRMC and mCDC were identified. SMARCB1 genomic alterations were significantly more frequent in mRMC than mCDC (P = 0.0002), but were the most common alterations in both subtypes. Mutations to EGFR, RET, NF2, and TSC2 were more frequently identified in mCDC versus mRMC. The median TMB and MSI-High status was low with <1% of mCCRC, mCDC, and mRMC having ≥ 20 mut/Mb.ConclusionGenomic alteration patterns in mCDC and mRMC differ significantly from mCCRCC. Targeted therapies for mCDC and mRMC appear limited with rare opportunities to target alterations in receptor tyrosine kinase and MTOR pathways. Similarly, TMB and absence of MSI-High status in mCDC and mRMC suggest resistance to immunotherapies.  相似文献   
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8.
The United States Department of Health and Human Services (HHS) leads the nation in preventing, preparing for, and responding to the adverse health effects of public health emergencies and disasters. In addition to biological, radiological and nuclear agents, the risk of a high consequence public health emergency due to the intentional and/or accidental release of chemical agents is a major growing concern of the US government. As such, the federal government is fully committed to address public health security threats posed by chemicals. To enhance chemical emergency preparedness and response, HHS oversees the interdepartmental research, advanced development, regulatory review and approval, procurement, and stockpiling of medical countermeasures (MCMs). Within the National Institute of Health (NIH/HHS), the National Institute of Allergy and Infectious Diseases (NIAID) is responsible for the fundamental research and early development of MCMs to prevent deaths and/or treat injuries during and after emergencies due to large scale chemical exposure. This commentary provides an overview of the NIAID/NIH Chemical Countermeasures Research Program (CCRP) and resources to facilitate the research, discovery, and early development of chemical MCMs. Available product development resources include research funding opportunities, expert advice from the NIH, and preclinical and efficacy service support cores to reduce opportunity costs and entry barriers for prospective developers interested in entering or accelerating the development of chemical MCMs.  相似文献   
9.
The effects of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in women on the gestation course and the health of the fetus, particularly in the first and second trimesters, remain very poorly explored. This report describes a case in which the normal development of pregnancy was complicated immediately after the patient had experienced Coronavirus disease 2019 (COVID-19) at the 21st week of gestation. Specific conditions included critical blood flow in the fetal umbilical artery, fetal growth restriction (1st percentile), right ventricular hypertrophy, hydropericardium, echo-characteristics of hypoxic-ischemic brain injury (leukomalacia in periventricular area) and intraventricular hemorrhage at the 25th week of gestation. Premature male neonate delivered at the 26th week of gestation died after 1 day 18 h due to asystole. The results of independent polymerase chain reaction (PCR), mass spectrometry and immunohistochemistry analyses of placenta tissue, umbilical cord blood and child blood jointly indicated vertical transmission of SARS–CoV-2 from mother to the fetus, which we conclude to be the major cause for the development of maternal vascular malperfusion in the studied case.  相似文献   
10.
The C-methylthio derivatives of cobalt bis(dicarbollide) were synthesized by reaction of anhydrous CoCl2 with nido-carborane [7-MeS-7,8-C2B9H11] and isolated as a mixture of rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] and meso-[1,2′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] isomers. The structures of both isomers were studied using DFT quantum chemical calculations. The most preferable geometry of rotamers and the stabilization energy of C-methylthio derivatives of cobalt bis(dicarbolide) were calculated. The (BEDT-TTF)[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] salt was prepared and its structure was determined by single crystal X-ray diffraction. The cisoid conformation of the rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] anion is stabilized by short intramolecular CH⋯S hydrogen and BH⋯S chalcogen bonds between the dicarbollide ligands, that is in good agreement with the data of quantum chemical calculations.

The C-methylthio derivatives of cobalt bis(dicarbollide) rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] and meso-[1,2′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] were synthesized and studied by DFT calculations and X-ray diffraction.  相似文献   
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