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51.
A case of a 48 year old female admitted to the hospital for further evaluation and treatment of an intracardiac tumour, is presented. The patient underwent surgical excision of the tumour localised in the right ventricular outflow tract with bioprosthetic tricuspid valve implantation and pacemaker insertion due to the procedure-related compete atrio-ventricular block. Histopathological examination revealed the presence of thyroid tissue in the excised tumour. Data published in literature dealing with this topic are reviewed. 相似文献
52.
Iwona Cygankiewicz Jerzy Krzysztof Wranicz Janusz Zaslonka Halina Bolinska Wojciech Zareba 《Annals of noninvasive electrocardiology》2003,8(4):289-295
Background: The aim of this study is to evaluate the association between heart rate turbulence (HRT) parameters and clinical characteristics of coronary artery disease (CAD) patients. Methods and Results: In 122 patients (mean age 62 ± 9 years) with angiographically documented CAD, 24‐hour Holter monitoring with HRT analysis was performed to evaluate turbulence onset (TO) and turbulence slope (TS). There was a significant correlation between TO and TS (P =?0.31; P < 0.001) . According to quartile values, TO ≥?0.37% and TS ≤ 4.25 ms/RR were considered as abnormal in this patient population. Average values of TO were higher and TS lower in patients over 60 years, in patients with a past history of myocardial infarction and in those with EF < 40%. Considering pharmacotheraphy, higher (better) values of TS were observed in patients on statins, nitrates, and beta‐blockers while lower TS values were noted in patients on calcium blockers. Patients with abnormal parameters of HRT compared to group with normal HRT values were characterized by features of more advanced CAD: age over 60 years (75% vs 49%), past history of MI (75% vs 64%), and EF < 40% (25% vs 3%). Multivariate analysis revealed age > 60 years (OR 1.27; P = 0.002) and EF < 40% (OR 1.39; P = 0.001) as independent clinical factors associated with abnormal HRT parameters. Conclusions: HRT parameters are influenced by clinical characteristics and pharmacotherapy of studied patients with TS more than abnormal TO depending on clinical characteristics of patients. Advanced age, prior myocardial infarction and left ventricular dysfunction are key factors influencing values of HRT parameters. 相似文献
53.
Immunofluorescence analysis of the primordial myosin detectable in embryonic striated muscle. 总被引:4,自引:0,他引:4 下载免费PDF全文
L J Sweeney W A Clark Jr P K Umeda R Zak F J Manasek 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(3):797-800
Immunofluorescence analysis showed that the earliest myosin detectable in both the embryonic chicken heart and somitic myotome, the precursor to skeletal muscle, was strongly reactive with two different monoclonal antibodies specific for the heavy chain of cardiac ventricular myosin, but it showed no reactivity with affinity-purified polyclonal antibodies specific for the heavy chains of either fast-twitch or slow-tonic skeletal myosins. The heart remained reactive exclusively with the antibodies to cardiac myosin throughout development, while late embryonic (day 20) skeletal muscles were strongly reactive only with their homologous skeletal myosin antibodies. Our findings suggest that the primordial myosin heavy chain detectable in both forms of embryonic chicken striated muscle, the myotome and the heart, is immunologically distinct from myosins expressed in later embryonic as well as adult skeletal muscles, but it contains antigenic determinants similar to those present in cardiac ventricular myosin. 相似文献
54.
Grzegorz Wozniak Maciej Misioek Adam Idasiak Iwona Dbosz-Suwiska Magdalena Jaworska Wieslaw Bal Boguslaw Maciejewski Leszek Miszczyk Krzysztof Skadowski Rafal Suwinski 《The British journal of radiology》2020,93(1116)
Objective:To compare the efficacy and tolerance of 7-days-a-week accelerated postoperative radiotherapy (p-CAIR) vs postoperative radio-chemotherapy (p-RTCT)Methods:Between September 2007 and October 2013, 111 patients were enrolled and randomly assigned to receive 63 Gy in 1.8 Gy fractions 7-days-a-week (n = 57, p-CAIR) or 63 Gy in 1.8 Gy fractions 5-days-a-week with concurrent cisplatin 80–100 mg per square meter of body-surface area on days 1, 22 and 43 of the radiotherapy course (p-RTCT). It represents approximately 40% of the intended trial size, that was closed prematurely due to slowing accrual. Only high-risk patients with squamous cell cancer of the oropharynx/oral cavity, considered fit for concurrent treatment were enrolled.Results:The rate of locoregional control (LRC) did not differ significantly between treatment arms (p = 0.18, HR = 0.56), 5 year LRC tended, however, to favour p-RTCT (81%) vs p-CAIR (62%). There was no difference in overall survival between treatment arms (p = 0.90, HR = 1.03).The incidence and severity of acute mucosal reactions and late reactions did not differ significantly between treatment arms. Haematological toxicity of p-RTCT was, however, considerably increased compared to p-CAIRConclusion:Concurrent postoperative RTCT tended to improve locoregional control rate as compared to p-CAIR. This, however, did not transferred into improved overall survival. Postoperative RTCT was associated with a substantial increase in haematological toxicity that negatively affected treatment compliance in this arm.Advances in knowledge:To our knowledge, this is the first trial that compares accelerated radiotherapy and radio-chemotherapy in postoperative treatment for oralcavity/oropharyngeal cancer 相似文献
55.
This paper discusses the results of studies on the transport of Ag(i) across polymer inclusion membranes (PIMs), derivatives of calixpyrroles with methyl (KP1) and carboxyl (KP2) groups, as ion carriers, o-nitrophenyl pentyl ether (o-NPPE) as a plasticizer and cellulose triacetate (CTA) as support. The influence of the pH of the source phase, metal concentration, stripping phase as well as carrier and plasticizer concentration on the efficiency of Ag(i) transport through PIM is presented. Long-term experiments with a supported liquid membrane and a plasticizer membrane demonstrate the durability of the studied PIMs. The obtained results indicate that the competitive transport of Cu(ii), Zn(ii), Ag(i) and Cd(ii) from the aqueous nitrate source phase through KP1 and KP2 is an effective separation method for Ag(i) ions. The prepared PIMs were characterized by scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques.The transport of Ag(i) across polymer inclusion membranes is reported with derivatives of calixpyrroles with methyl (KP1) and carboxyl (KP2) groups as ion carriers, o-nitrophenyl pentyl ether as a plasticizer and cellulose triacetate as support. 相似文献
56.
This study assesses whether in vitro immediate release ketorolac tablet dissolution profiles (utilizing the recently proposed USP dissolution test for ketorolac tablets) can be correlated with in vivo plasma pharmacokinetic parameters. Four batches of ketorolac tablets were utilized: a ketorolac tablet batch that demonstrated a rapid dissolution rate during USP in vitro dissolution testing, two tablet batches that were manufactured such that they dissolved at moderate rates, and a tablet batch that was manufactured such that it dissolved at a distinctly slow rate. The single-dose mean pharmacokinetic characteristics and relative bioavailability of the four different 10 mg ketorolac tromethamine tablets were evaluated in 12 healthy volunteers in a randomized study of Latin square design. The amount dissolved of the various tablets at 10, 20, and 30 min was in the order of fast-dissolving tablets > medium-1-dissolving tablets=medium-2-dissolving tablets > slow-dissolving tablets. In general, the profiles of the average plasma concentrations for ketorolac were similar for the fast- and the two medium-dissolving tablet batches (even though a statistically significant difference was found between the tmax of the fast-dissolving tablet and one of the medium-dissolving tablet batches). The mean plasma concentrations for the slow-dissolving tablet, however, reached peak levels much later, with the peak also being significantly smaller. There were no statistically significant differences in the total AUC or in the mean plasma half-lives among the four formulations. Good correlations were obtained for mean tmax versus the percentage dissolved at 20, 30, and 45 min. Correlations were generally weaker for percentage dissolved versus Cmax or percentage bioavailability. This indicates that in vitro dissolution testing for immediate release ketorolac tablets can be a useful indicator of in vivo time to maximum plasma concentration when comparing similarly formulated tablets. Further, the proposed USP dissolution test and specification would have appropriately failed the slow-dissolving tablet batch, which demonstrated a significantly slower rate of absorption as per tmax and Cmax. 相似文献
57.
Magdalena Barwiolek Dominika Jankowska Mateusz Chorobinski Anna Kaczmarek-Kdziera Iwona akomska Slawomir Wojtulewski Tadeusz M. Muzio 《RSC advances》2021,11(40):24515
Two Zn(ii) complexes, K1 and K2, obtained from the template reaction of zinc(ii) acetate dihydrate with o-phenylenediamine and 2-hydroxy-5-methylisophthalaldehyde (K1) or 2-hydroxy-5-tert-butyl-1,3-benzenedicarboxaldehyde (K2), respectively, were characterized by X-ray crystallography, spectroscopic (UV-vis, fluorescence and IR), and thermal methods. In the complex [Zn2(MeO)1.4(OH)0.6(L1)]·2H2O K1, there are two binding sites in the macrocyclic ligand and they are occupied by zinc(ii) cations found in slightly distorted square pyramidal environment. The zinc(ii) cations are connected by slightly asymmetric oxo bridges with a Zn1–O14–Zn1[−x, −y + 1, −z + 1] angle of 104.8(2)°. In the dimer [Zn2(CH3COO)2(L2)]·2EtOH K2, there are two crystallographically independent binding sites both occupied by zinc(ii) cations. There is a significant difference between both complexes, since in K1 only one site is independent and the second is occupied due to the application of symmetry rules, and the geometry of both sites is identical. Thin layers of the obtained Zn(ii) complexes were deposited on Si(111) by the spin coating method and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), fluorescence spectroscopy and ellipsometry. In the non-absorbing range, the value of the refractive index exhibits normal dispersion between 1.8 and 2.1 for K1_1–K1_3; and between 2.3 and 2.6 for the K2 series of samples established for long wavelengths (longer than 500 nm). The Zn(ii) complexes and their thin layers exhibited fluorescence between 534–573 nm and 495–572 nm for the compounds and the layers, respectively. The highest quantum yield of fluorescence was achieved for K2 in benzene and in the solid state ϕ = 0.78 and 0.58, respectively. The influence of the solvent polarity on the fluorescence properties of the obtained complexes was studied. Additionally, DFT calculations were performed to explain the structures and electronic spectral properties of the complexes.Tin fluorescent materials were obtained using a spin coating method. 相似文献
58.
Background: A well-balanced nutritional diet pattern has a significant role in the management of diet-related disorders. Currently, there are no specific dietary guidelines to refer to when advising non-diabetic patients with symptoms attributed to hypoglycemia in the postprandial period or patients with confirmed reactive hypoglycemia (RH). The aim of this study was to investigate the impact of the dietary interventions, and their sustained outcome, on the severity of hypoglycemic-like symptoms occurring in non-diabetic patients. Methods: The study group included forty non-diabetic individuals with symptoms consistent with RH. At the baseline, each patient underwent RH diagnosis and complex dietary evaluation. Over a period of six months, each patient had four appointments with a dietitian. Two sessions were focused on a dietary education about low glycemic index diet (LGID) and Mediterranean diet (MD). The said diets were to be followed for a period of three months, with two additional dietary check-ups. Once dietary supervision was completed, patients had no imposed dietary patterns. The final follow-up appointment took place twelve months later and that is when each patient underwent a detailed assessment of their current dietary habits and evaluation of the frequency of symptoms consistent with hypoglycemia. Results: There was a statistically significant reduction in the severity in eight out of the ten analyzed hypoglycemic-like symptoms after the dietary interventions. The most significant change was observed in the following symptoms: hunger (η2 = 0.66), impaired concentration (η2 = 0.61), hand tremor (η2 = 0.55), and fatigue (η2 = 0.51). The outcomes were comparable for both recommended diets, the LGID and the MD. The reduction in hypoglycemic-like symptoms continued after the twelve-month period. The individualized dietary counselling significantly improved the patients’ eating habits in comparison to those present prior to intervention in terms of healthy diet index (F(2,78) = 27.30, p < 0.001, η2 = 0.41, 90%CI [0.26; 0.51]) and unhealthy diet index (F(2,78) = 433.39, p < 0.001, η2 = 0.91, 90%CI [0.89; 0.93]). Conclusions: Healthy modifications in dietary habits may improve patient’s well-being and reduce the severity of their postprandial symptoms attributed to hypoglycemia. Therefore, dietary intervention focused on appropriate nutritional management combined with follow-up consultations may be a beneficial step towards comprehensive treatment of non-diabetic patients who present with hypoglycemic-like symptoms in the postprandial period. 相似文献
59.
Iwona Chlebicka Alicja Ryga Aleksandra A. Stefaniak Jacek C. Szepietowski 《Dermatologic therapy》2020,33(3)
This is a case presentation of successful defect repair after radical surgical excision of a moderately large basal cell carcinoma by a simple procedure taking advantage of a patient's individual face features. 相似文献
60.
Lei Yue Dan Xu Ziyu Wei Tingting Zhao Tao Lin Reshef Tenne Alla Zak Quanjun Li Bingbing Liu 《Materials》2022,15(8)
Exploring the behavior of nanocrystals with varying shapes and sizes under high pressure is crucial to understanding the relationship between the morphology and properties of nanomaterials. In this study, we investigated the compression behaviors of WS2 nanotubes (NT-WS2) and fullerene-like nanoparticles (IF-WS2) by in situ high-pressure X-ray diffraction (XRD) and Raman spectroscopy. It was found that the bulk modulus of NT-WS2 is 81.7 GPa, which is approximately twice as large as that of IF-WS2 (46.3 GPa). This might be attributed to the fact that IF-WS2 with larger d-spacing along the c-axis and higher defect density are more compressible under isotropic pressure than NT-WS2. Thus, the slender NT-WS2 possess a more stable crystal structure than the IF-WS2. Our findings reveal that the effects of morphology and size play crucial roles in determining the high-pressure properties of WS2 nanoparticles, and provide significant insight into the relationship between structure and properties. 相似文献