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41.
Athar Khalil Khalil Al Handawi Zeina Mohsen Afif Abdel Nour Rita Feghali Ibrahim Chamseddine Michael Kokkolaras 《Viruses》2022,14(7)
The rapid spread of the coronavirus disease COVID-19 has imposed clinical and financial burdens on hospitals and governments attempting to provide patients with medical care and implement disease-controlling policies. The transmissibility of the disease was shown to be correlated with the patient’s viral load, which can be measured during testing using the cycle threshold (Ct). Previous models have utilized Ct to forecast the trajectory of the spread, which can provide valuable information to better allocate resources and change policies. However, these models combined other variables specific to medical institutions or came in the form of compartmental models that rely on epidemiological assumptions, all of which could impose prediction uncertainties. In this study, we overcome these limitations using data-driven modeling that utilizes Ct and previous number of cases, two institution-independent variables. We collected three groups of patients (n = 6296, n = 3228, and n = 12,096) from different time periods to train, validate, and independently validate the models. We used three machine learning algorithms and three deep learning algorithms that can model the temporal dynamic behavior of the number of cases. The endpoint was 7-week forward number of cases, and the prediction was evaluated using mean square error (MSE). The sequence-to-sequence model showed the best prediction during validation (MSE = 0.025), while polynomial regression (OLS) and support vector machine regression (SVR) had better performance during independent validation (MSE = 0.1596, and MSE = 0.16754, respectively), which exhibited better generalizability of the latter. The OLS and SVR models were used on a dataset from an external institution and showed promise in predicting COVID-19 incidences across institutions. These models may support clinical and logistic decision-making after prospective validation. 相似文献
42.
Nehal Elkhoshkhany Samir Marzouk Mohammed El-Sherbiny Heba Ibrahim Bozena Burtan-Gwizdala Mohammed S. Alqahtani Khalid I. Hussien Manuela Reben El Sayed Yousef 《Materials》2022,15(15)
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection. 相似文献
43.
Navneet Kumar Ruchi Kant Pawan Kumar Maurya Syed Ibrahim Rizvi 《Phytotherapy research : PTR》2012,26(11):1644-1647
Although the antioxidant properties of flavonoids are well documented, it is still unclear whether these effects are dependent on radical scavenging or iron chelating activities. Oxidative stress, a state of excessive reactive oxygen species (ROS) activity, is associated with vascular disease conditions such as hypertension. Both the anti‐ and pro‐oxidant effects of tea catechins have been implicated in the alterations of cellular functions that determine their chemoprotective and therapeutic potentials in health and diseases. The present study examined the concentration dependent (10?7 to 10?4 m ) effects of (?)‐epicatechin and L‐ascorbic acid on Na+/K+‐ATPase and Ca2+‐ATPase activity in hypertensive patients and normal subjects. L‐ascorbic acid has been used as a positive control to compare the effect of (?)‐epicatechin. A significant (p < 0.0001) decrease in the activities of Na+/K+‐ATPase and Ca2+‐ATPase was observed in hypertensive patients compared with normal subjects. We report that (?)‐epicatechin shows a significant (p < 0.001) dose‐dependent protective effect against oxidative stress induced by tert‐butyl hydroperoxide (t‐BHP), which is manisfested as a decrease in the activity of erythrocyte Na+/K+‐ATPase and Ca2+‐ATPase, in hypertensive patients as well as normal subjects. The effect of L‐ascorbic acid was also significant (p < 0.001) and was comparable with that of (?)‐epicatechin. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
44.
Ibrahim M.A. Hassanin Ahmed T. Abdel-Hafeez Sherif A. El-Nashar 《International journal of gynaecology and obstetrics》2008,103(3):222-226
Objective
To assess the safety and short-term efficacy of bilateral uterine artery ligation (UAL) via minilaparotomy for the management of heavy menstrual bleeding (HMB).Methods
A prospective study of 30 women with HMB who underwent UAL. The primary outcome was cumulative treatment failure 12 months after the procedure. Treatment failure was defined as the need for hysterectomy during the follow-up period.Results
At 12 months, 6 women had undergone hysterectomy for bleeding, for a cumulative failure rate of 20% (95% CI, 9%-38%). The number of bleeding days was significantly reduced by 11.9 ± 1.5 days (P < 0.001) and hemoglobin level significantly increased by 1.3 ± 0.15 g/dL (P < 0.001). Of the 30 women, 24 (80%) were satisfied with the results. No major complications were reported during the procedure or median follow-up period of 13.2 months.Conclusion
Bilateral UAL is a safe and effective minimally invasive procedure that can provide an alternative treatment for HMB. 相似文献45.
Esinler I Aktas D Otegen U Alikasifoglu M Yarali H Tuncbilek E 《Reproductive biomedicine online》2008,16(3):356-360
The aim of this study was to assess the rates of variant alleles of cytochrome P4501A1 (CYP1A1) in patients with polycystic ovary syndrome (PCOS). It was designed as a case-control study in Hacettepe University, Faculty of Medicine, Department of Obstetrics and Gynecology and Genetics. Forty-eight patients with PCOS served as the study group. Ninety-six regularly cycling women with no clinical and biochemical evidence of hyperandrogenism and polycystic ovary appearance served as the controls. The CYP1A1 variant alleles of all patients were determined via polymerase chain reaction. The rate of the CYP1A1 isoleucine (Ile)/valine (Val) allele was significantly higher in patients with PCOS than in the controls (OR: 7.8, 95% CI: 3.45-17.52, P < 0.001). However, there was no statistically significant difference in the distribution of Val/Val genotype (OR: 4.0, 95% CI: 0.60-26.73). The rate of any Val genotype (Ile/Val or Val/Val) was significantly higher in patients with PCOS compared with the control group (OR: 7.4, 95% CI: 3.33-16.46, P < 0.001). In conclusion, the patients with PCOS had a 7.8-fold higher frequency of CYP1A1 Ile/Val genotype and a 7.4-fold higher frequency of CYP1A1 of any Val genotype (Ile/Val or Val/Val). 相似文献
46.
Yetish Sing Pratistadevi K Ramdial Tasnim Ibrahim 《International journal of gynecological pathology》2008,27(1):37-40
This report describes a 25-year-old human immunodeficiency virus- seropositive patient who initially presented with clinical features of a tuboovarian abscess. After a poor response to antibiotic therapy, laparotomy and excision of a right-sided, unilocular, pseudocystic ovarian mass measuring 140 x 80 x 60 mm were undertaken. Mucoid gelatinous material, with a glistening appearance and slimy consistency, coated the inner surface of the thick wall. The cyst contained clear, viscid fluid with a similar slimy consistency. Although the macroscopic diagnosis was that of an ovarian mucinous cystadenocarcinoma, histopathologic assessment confirmed a well-circumscribed pseudocystic cryptococcoma with a wall of granulation and fibrous tissue and compressed ovarian stroma. The inner surface was covered by large, paucireactive, extracellular "yeast lakes" of carminophilous Cryptococcus neoformans yeasts of varying shape and size. To the best of our knowledge, this is the first documentation of ovarian cryptococcosis in the English language literature. Despite their rarity in the female genital tract, fungal infections must be considered in the differential diagnosis of patients presenting with pelvic pain of obscure origin and a pelvic mass that is refractory to antibiotic therapy. 相似文献
47.
48.
Symptomatic hypocalcemia has been reported infrequently in association with magnesium sulfate (MgSO (4)) tocolytic therapy. We report a 38-year-old woman who presented in preterm labor at 24 3/7 weeks. Twenty hours after starting MgSO (4), she developed chest pain. Studies revealed therapeutic serum Mg level, total serum calcium (Ca) = 5.5 mg/dL, 24-hour urine Ca = 763.9 mg, and low serum uric acid and phosphate levels. All studies corrected day 1 postpartum; urine Ca level corrected on day 2. Even short courses of MgSO (4) can result in severe hypocalcemia, raising the question of whether Ca levels should be routinely monitored. 相似文献
49.
50.
Jack Ogilvie Raymond Zhao Sandra Camelo-Piragua Mohannad Ibrahim Remy Lobo John Kim 《Radiology Case Reports》2022,17(8):2820
Amyloidomas are focal solitary amyloid masses without systemic involvement that have been observed to occur in various body locations. When presenting intracranially, they pose a challenging diagnostic and therapeutic course given their location and rarity. We report a case of a 62-year-old man with a 4-year history of seizure and headaches. Magnetic resonance imaging was initially inconclusive but revealed an ill-defined right temporal lobe lesion. Biopsy later confirmed a cerebral amyloidoma. We also review the current literature on the pathogenesis, imaging findings, prognosis, and treatment of cerebral amyloidomas. 相似文献