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Gamma induced changes in Makrofol/CdSe nanocomposite films 被引量:1
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作者 Ali A.Alhazime M.ME.Barakat +4 位作者 Radiyah A.Bahareth E.M.Mahrous Saad Aldawood S.Abd El Aal S.A.Nouh 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期547-553,共7页
We applied an ex-situ casting procedure to prepare a nanocomposite(NCP)from Makrofol polycarbonate(PC)and CdSe nanoparticles.The CdSe nanoparticles were prepared by a thermolysis procedure in the presence of N_(2) gas... We applied an ex-situ casting procedure to prepare a nanocomposite(NCP)from Makrofol polycarbonate(PC)and CdSe nanoparticles.The CdSe nanoparticles were prepared by a thermolysis procedure in the presence of N_(2) gas flow.Rietveld refinement of x-ray data illustrated that the CdSe adopts a cubic zinc blend structure of 6.057 A lattice parameter and 2 nm typical grain size.Samples from the prepared NCP were exposed to γ dosages(20 kGy-250 kGy).The modifications induced in the NCP films owing to γ dosages have been studied.Theγirradiation(50 kGy-250 kGy)causes crosslinks that reduce the optical bandgap from 4.15 eV to 3.81 eV,associated with an increase in dielectric parameters and refractive index.This is attributed to an increase in the mass fraction of the disordered regions as specified by x-ray diffraction.The PC-CdSe NCP was found to have a reaction to color modification which makes it suitable for saleable reproduction on a printing press. 展开更多
关键词 GAMMA NANOCOMPOSITE x-ray dfraction UV spectra color changes
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Biochemical and Molecular Effects of <i>Phoenix dactylifera</i>and <i>Ziziphus spina-christi</i>Extracts on <i>Candida albicans</i>
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作者 Sara Al-Ali Awatif Al-Judaibi 《Journal of Biosciences and Medicines》 2019年第3期29-43,共15页
Our overall knowledge of the medicinal uses of plants suggests that natural compounds could be useful in the treatment of cutaneous fungal infections in tropical regions. Furthermore, the possibilities of treatment us... Our overall knowledge of the medicinal uses of plants suggests that natural compounds could be useful in the treatment of cutaneous fungal infections in tropical regions. Furthermore, the possibilities of treatment using plant extracts may be even broader than is already known when one considers plants that have not been extensively studied in this context, such as the regional species Phoenix dactylifera and Ziziphus spina-christi. This study compared the antimicrobial activity of Phoenix dactylifera and Ziziphus spina-christi extracts in terms of their biochemical and molecular effects on Candida albicans (ATCC CA 10231). These effects included altered levels of intracellular sterols, changes in the permeability of the cell membrane, and changes in the TEF1: QRTTEF1, CaERG1: ERG1, CdERG12: CdERG1, and ERG25: ERG25 genes. Scanning electron microscopy (SEM) was used to identify morphological characteristics, and energy-dispersive X-ray spectroscopy (EDAX) analyses were conducted. In treated samples, the SEM and EDAX analyses showed cell cavities and shrinkage of the cell wall, and the number of cells was reduced to only a few abnormal cells as compared with that in the untreated samples. Yttrium was detected in the cells treated with Z. spina-christi, and high levels of osmium were detected in the cells treated with P. dactylifera. Compared with control cells, cells exposed to the concentration 150 μl/ml of Z. spina-christi extract had an average sterol concentration that was nearly 3 times higher, while the concentration was 5.5 times higher for cells treated with the 150 μl/ml of P. dactylifera extract. The ethanol extracts affected the permeability of C. albicans cell membrane. Gene sequencing showed gaps and mismatches in the ERG1, ERG12, and ERG25 genes after treatment with P. dactylifera and Z. spina-christi extracts compared with that in the controls. The results were highly significant (p ≤ 0.01). We conclude that the ethanol extracts of P. dactylifera and Z. spina-christi have antimicrobial activity through several mechanisms in the yeast cell. 展开更多
关键词 Sterols Cell Permeability EDAX Analyses Phoenix dactylifera ZIZIPHUS spina-christi MOLECULAR Characterization
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Effect of Vitex agnus-castus plant extract on polycystic ovary syndrome complications in experimental rat model
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作者 Amal H.Hamza Widad M.AlBishri Mona H.Alfaris 《Asian pacific Journal of Reproduction》 2019年第2期63-69,共7页
Objective: To investigate ameliorative effects of Vitex agnus-castus (VAC) and VAC containing pharmaceutical supplement (VPS) against polycystic ovary syndrome (PCOS). Methods: PCOS in the rats was induced by daily ad... Objective: To investigate ameliorative effects of Vitex agnus-castus (VAC) and VAC containing pharmaceutical supplement (VPS) against polycystic ovary syndrome (PCOS). Methods: PCOS in the rats was induced by daily administration of letrozole at 1 mg/kg body weight concentration for 21 d. PCOS rats were then treated daily either with metformin, VAC plant extract or VPS at 70, 8 or 8 mg/kg body weight concentration for 15 d. Rats that received none of these treatments were considered as control. Blood and ovaries were collected from all the rats. Serum glucose, cholesterol, triglyceride and high density lipoprotein-cholesterol were measured spectrophotometrically. Serum insulin, estrogen, progesterone, testosterone, luteinizing hormone, follicle-stimulation hormone, catalase, superoxide dismutase, malondialdehide and reduced glutathione were measured using enzyme-linked immunosorbent assay. Results: Rats treated with letrozole demonstrated a significant increase in serum testosterone, estrogen, cholesterol, luteinizing hormone, triglycerides, glucose, insulin, and malondialdehide levels, and a significant decline in progesterone, follicle-stimulating hormone, high density lipoprotein-cholesterol, catalase and reduced glutathione levels compared to control. Contrarily, no significant change in superoxide dismutase was noted in response to letrozole treatment. Rats treated with metformin, VAC or VPS showed a remarkable reversal in the levels of parameters affected by letrozole treatment. Conclusions: Data indicate that VAC and VPS exert potential ameliorative effects against PCOS through the modulation of hormonal and lipid profile as well as oxidative stress. Moreover, the favorable effects of these compounds are comparable to that of metformin. 展开更多
关键词 POLYCYSTIC OVARY syndrome VITEX agnus-castus METFORMIN Sexual HORMONES Oxidative stress Lipid profile
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Covid-19’s Pandemic Relationship to Saudi Arabia’s Weather Using Statistical Analysis and GIS
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作者 Ranya Fadlalla Elsheikh 《Computer Systems Science & Engineering》 SCIE EI 2022年第8期813-823,共11页
The eruption of the novel Covid-19 has changed the socio-economic conditions of the world.The escalating number of infections and deaths seriously threatened human health when it became a pandemic from an epidemic.It ... The eruption of the novel Covid-19 has changed the socio-economic conditions of the world.The escalating number of infections and deaths seriously threatened human health when it became a pandemic from an epidemic.It developed into an alarming situation when the World Health Organization(WHO)declared a health emergency in MARCH 2020.The geographic settings and weather conditions are systematically linked to the spread of the epidemic.The concentration of population and weather attributes remains vital to study a pandemic such as Covid-19.The current work aims to explore the relationship of the population,weather conditions(humidity and temperature)with the reported novel Covid-19 cases in the Kingdom of Saudi Arabia(KSA).For the study,the data for the reported Covid-19 cases was secured from 11 March 2020,to 21 July 2020(132 days)from the 13 provinces of KSA.The Governorate level data was used to estimate the population data.A Geographic information system(GIS)analysis was utilised to visualise the relationship.The results suggested that a significant correlation existed between the population and Covid-19 cases.For the weather conditions,the data for the 13 provinces of KSA for the same period was utilised to estimate the relationship between the weather conditions and Covid-19 cases.Spearman’s rank correlation results confirmed that the humidity was significantly linked with the reported cases of Covid-19 in Makkah,Aseer,Najran,and Al Baha provinces.The temperature had a significant relation with the reported Covid-19 cases in Al-Riyad,Makkah,Al-Madinah,Aseer,Najran,and Al-Baha.The inconsistency of the results highlighted the variant behavior of Covid-19 in different regions of the KSA.More exploration is required beyond the weather-related variables.Suggestions for future research and policy direction are offered at the end of the study. 展开更多
关键词 Covid-19 GIS TEMPERATURE spearman correlation humidity Saudi Arabia
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Glycated Hemoglobin HbA1c:Permittivity Experimental Applications with Some Mathematical Concepts,Temperature and Frequency Variations
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作者 Soliman Abdalla Sherif Kandil +1 位作者 Waleed El-Shirbeeny Fatma Bahabri 《Journal of Renewable Materials》 SCIE EI 2022年第9期2335-2354,共20页
Diabetes disorder turns smoothly to be a global epidemic disorder and the glycated hemoglobin(HbA1c)starts to be an efficient marker of it.The dielectric spectroscopy on different human normal-and diabetic-blood sampl... Diabetes disorder turns smoothly to be a global epidemic disorder and the glycated hemoglobin(HbA1c)starts to be an efficient marker of it.The dielectric spectroscopy on different human normal-and diabetic-blood samples is used to characterize and to estimate the HbA1c concentration.“dc-”and ac-measurement of the complex conductivity in the temperature range from 280 K up to 320 K,and in the frequency range from one Hz up to 32 MHz have been performed.The thermal activation energy,ΔEσ,of dc-electric conductivity lies in the range 95 meV<ΔEσ<115 meV;while the thermal activation energy,ΔEτ,of RBCs relaxation time is aboutΔEτ=140 meV.The experimental data have been modeled by a physical-model and good fittings have been found between calculated and experimental values.The effective number of charges,nG,T,is estimated after Cole and Cole curves.One has found that nG,T increases with both temperature,T,and with the glycation rate GG.This increase may shed some light on an effective and possible way to treat(and to detect)diabetes disorders via eliminating the excess electric charges produced by glycation processes.The present work sheds the light on the possible combination of focused ultrasound with magnetic resonance imaging to study the dielectric-thermal variations of glycated-RBCs,which can lead to very precise and non-invasive monitoring of glycation concentration in vivo and in vitro via magnetic resonance-thermometry. 展开更多
关键词 Glycated-hemoglobin rate thermal characterization red blood cells RBCs relaxation of RBCs dielectric constant mathematical model
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Complete Monotonicity of Functions Related to Trigamma and Tetragamma Functions
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作者 Mona Anis Hanan Almuashi Mansour Mahmoud 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第4期263-275,共13页
In this paper,we study the completely monotonic property of two functions involving the functionΔ(x)=[ψ′(x)]2+ψ″(x)and deduce the double inequality x^(2)+3x+3/3x^(4)(2x+1)^(2)<Δ(x)<625x^(2)+2275x+5043/3x^(... In this paper,we study the completely monotonic property of two functions involving the functionΔ(x)=[ψ′(x)]2+ψ″(x)and deduce the double inequality x^(2)+3x+3/3x^(4)(2x+1)^(2)<Δ(x)<625x^(2)+2275x+5043/3x^(4)(50x+41)^(2),x>0which improve some recent results,whereψ(x)is the logarithmic derivative of the Gamma function.Also,we deduce the completely monotonic degree of a function involvingψ′(x). 展开更多
关键词 Trigamma function tetragamma function completely monotonic function completely monotonic degree INEQUALITY
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A Study on the Inj-Equitable Graph of a Graph
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作者 Hanaa Alashwali Ahmad N. Alkenani +1 位作者 A. Saleh Najat Muthana 《Applied Mathematics》 2018年第3期264-273,共10页
For any graph G, the Inj-equitable graph of a graph G, denoted by IE (G) , is the graph with the same vertices as G and for any two adjacent vertices u and v in IE (G), ≤ 1, where for any vertex w∈V (G) , degin (w)?... For any graph G, the Inj-equitable graph of a graph G, denoted by IE (G) , is the graph with the same vertices as G and for any two adjacent vertices u and v in IE (G), ≤ 1, where for any vertex w∈V (G) , degin (w)?= . In this paper, Inj-equitable graphs of some graphs are obtained, and some properties and results are established. Moreover, complete Inj-equitable graph and the Inj-equitable graph are defined. 展开更多
关键词 DOMINATION INJECTIVE Equitable GRAPH Equitable MATRIX INJECTIVE MATRIX
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A Study of Chemical, Mineral Compositions (of Some Metals) and Natural Radioactivity in Porcelain and Ceramic Dinner Ware
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作者 Safia H. Q. Hamidalddin 《Journal of Geoscience and Environment Protection》 2020年第11期209-221,共13页
Fifteen Porcelain and Ceramic Dinner Wares samples (collected from local commercial suppliers—Jeddah Saudi Arabia) were studied applying X-Ray Diffraction and Atomic Absorption techniques were used to study the Chemi... Fifteen Porcelain and Ceramic Dinner Wares samples (collected from local commercial suppliers—Jeddah Saudi Arabia) were studied applying X-Ray Diffraction and Atomic Absorption techniques were used to study the Chemical, Mineral, Compositions Concentrations (of Some Metals). In addition, the Natural Radioactivity measurements of <sup>226</sup>Ra, <sup>232</sup>Th and <sup>40</sup>K, was used by a high-purity germanium (HPGe) detector. X-ray diffraction results showed that the major mineral constituents of 15 samples were quartz (SiO<sub>2</sub>) (except one), minor and trace elements vary from sample to sample. Atomic absorption spectroscopy results of the concentrations for (Al, Pb, Bi, U, Th and K) in (ppm) showed that Al<sub>2</sub>O average was 10.3 (ppm) (10%) less than the acceptable value. PbO, its average was 1.65 ppm which was slightly greater than the allowed value 1.35 ppm. Bi concentrations for all samples were lower than (DL < 10). For most samples U, concentrations were lower than (DL < 5) except samples C9 and C11. Th concentrations ranged from LDL (<1 to 52.88) and were much greater than the acceptable value 7.24 ppm except samples P1, P2, P4. The potassium concentration average was greater than the acceptable value. The average concentrations of <sup>238</sup>U, <sup>232</sup>Th and <sup>40</sup> K were (83.83, 91.05 and 751.07) Bq/kg dry. The radium equivalent activity concentration <em>Ra</em><sub><em>eq</em></sub> (Bq/kg) (302.61) was less than recommended value (370), gamma dose rate <em>D</em> (nGy/h) average (140.15) was much higher than the recommended value (60) (UNSCEER). <em>D</em><sub><em>eff</em></sub> (mSv/year) and <em>H</em><sub><em>ix</em></sub> were below the published admissible limit ≤ 1 and the risk is negligible. This study offers needed information for consumers at exposure risk and is useful to be found in terms of radiation protection. 展开更多
关键词 X-Ray Diffraction Atomic Absorption Gamma-Ray Spectroscopy Natural Radioactivity Dinnerware
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Effects of Biochemical and Molecular Inhibitors of Plant Extracts on Pathogenic Bacteria
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作者 Ashwag Al-Zahrani Effat Al-Judaibi +1 位作者 Hanan Omar Awatif Al-Judaibi 《Journal of Biosciences and Medicines》 2017年第5期44-55,共12页
The study aimed to evaluate the effect of the green alga Ulva lactuca and medicinal plant Nigella sativa extract on the activity of Staphylococcus aureus and Pseudomonas aeruginosa. The bacteria were incubated with th... The study aimed to evaluate the effect of the green alga Ulva lactuca and medicinal plant Nigella sativa extract on the activity of Staphylococcus aureus and Pseudomonas aeruginosa. The bacteria were incubated with the crude extracts and extracellular free potassium and phosphorus ions were measured in the medium. The levels of potassium and phosphorous were the maximum in the medium of S. aureus treated with N. sativa extract. The medium of P. aeruginosa incubated with U. lactuca extract was found to have the lowest phosphorous and the greatest potassium levels. The highest activity against P. aeruginosa was noticed with U. lactuca extract, where it caused reduction in the dry weight and glucose consumption of bacteria estimated by 28.41% and 41.09%, respectively. The antibacterial activity of N. sativa extract was the greatest against S. aureus and recorded 32.59% and 39.96% reduction in the bacterial dry weight and glucose uptake, respectively. Scanning Electron Microscopy study showed morphological changes in the cell wall of treated bacteria. The treatment of bacteria with the tested extract induced gene mutations. The results assessed the possible application of U. lactuca and N. sativa as a source of pharmacological benefits. 展开更多
关键词 Natural Products ANTIBACTERIAL Activity BIOCHEMICAL Analysis MOLECULAR ANALYSES MORPHOLOGICAL Changes
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Radiological Effectual and Mineral Salts Measurements of Sandstone Used in the Construction from Al Wajh, Al Ula and North Al Ula, Az Zabirah-Saudi Arabia
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作者 Safia H. Q. Hamidalddin 《Journal of Geoscience and Environment Protection》 2022年第9期84-95,共12页
The activity concentrations of natural radionuclides <sup>226</sup>Ra, <sup>232</sup>Th and <sup>40</sup>K, were measured in (16) sandstone samples collected from two regions of Sau... The activity concentrations of natural radionuclides <sup>226</sup>Ra, <sup>232</sup>Th and <sup>40</sup>K, were measured in (16) sandstone samples collected from two regions of Saudi Arabia, Region 1 (Al Wajh on Red Sea coast and Al Ula north-East of Medina), Region 2 (North of Al Ula and Az Zabirah, North-West of Hail) by (HPGe gamma spectrometer). The activity concentration average values of the radionuclides <sup>226</sup>Ra, <sup>232</sup>Th, and <sup>40</sup>K in the sandstone samples (Region 1) ranged from 10.97 ± 0.43, 27.68 ± 0.37 and 64.56 ± 0.74 Bq/kg respectively. These values are less than the international values reported by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000), in (Region 2), average values ranged from 2465.49 ± 0.00, 2042.00 ± 0.00 and 2259.65 ± 0.64 Bq/kg respectively. These values are higher than the values reported by (UNSCEAR, 2000). Average values of radium equivalent activity Ra<sub>eq</sub> (Bq/Kg), absorbed dose rate D (nGy/h), annual effective radiation dose D<sub>eff</sub> (mSv/y), External index (H<sub>ex</sub>) and Internal index (H<sub>in</sub>) were in (region 1) 21.13, 27.22, 11.75, 0.07 and 0.10 respectively, in (region 2) 5775.19, 1787.78, 846.58, 11.57 and 15.64 respectively. These results are lower (except annual effective radiation dose) in (region 1) and higher in (region 2) than the world recommended values by (UNSCEAR, 2000). Also, samples were analyzed by Atomic Absorption spectrometer (AAS) for Al, Ca, Fe, K, Mg and Bi in % elements concentrations. Average value in (region 1) (Al Wajh and Al Ula) are 4.42, 0.41, 1.37, 0.04 and 0.03, (in region 2) (N. Al Ula and Az Zabirah) are 12.50, 10.05, 1.01, 1.19, 0.04 respectively. Classifications of sandstone depend on the content of these elements. These results are important for the safety of dwellers and user of sandstone in constructions. 展开更多
关键词 Gamma Spectrometer AA Spectrometer Natural Radioactivity Chemical Elements
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Elemental Compositions of Some Eye Shadow Products Marketed in Saudi Arabia
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作者 Faten M. Ali Zainy Fatima Bannani Ohoud A. Alotaibi 《Journal of Cosmetics, Dermatological Sciences and Applications》 2018年第4期236-243,共8页
This study focuses on the determination, as well as, the composition of some heavy metals contained in 12 eye shadow cosmetic samples. An elemental analysis of heavy metals (Ti, Cr, Fe, Ni, Cu, Co, Mn, Pb, and Zn) was... This study focuses on the determination, as well as, the composition of some heavy metals contained in 12 eye shadow cosmetic samples. An elemental analysis of heavy metals (Ti, Cr, Fe, Ni, Cu, Co, Mn, Pb, and Zn) was performed by X-ray Fluorescence. The constitution of some samples was studied by Powder X-Ray Diffraction. Heavy metals exist as zinc oxide, Titanium dioxide, Iron oxide, Bismuth oxychloride, and lead sulfide. The quantification of selected toxic heavy metals lead, copper and nickel were achieved by Inductively Coupled Plasma-Optical Emission Spectrometry after digestion with concentrated acids. In all analyzed samples lead had a concentration less than 20 ppm, which indicated good manufacturing practice. Copper and nickel levels were within acceptable concentrations, but overpasses the safe limit appeared in China samples. The prolonged use of cosmetics case an allergic problem for consumers. Therefore, quality controls are highly controlled for imported products with different regulations. 展开更多
关键词 COSMETIC Eye SHADOW HEAVY Metals ICP XRD XRF
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A GIS Tool That Provides Intelligent Solutions in Emergency Departments during COVID-19
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作者 Ranya Fadlalla Elsheikh 《Journal of Geographic Information System》 2022年第3期280-293,共14页
The response to the COVID-19 pandemic has led to a revolution in open geographic information system (GIS) sources and Web GIS, which have grown considerably. Patient handover and crowding are critical issues to addres... The response to the COVID-19 pandemic has led to a revolution in open geographic information system (GIS) sources and Web GIS, which have grown considerably. Patient handover and crowding are critical issues to address during the COVID-19 pandemic. Saudi Arabia’s Vision 2030 aims to optimise quality and resource utilisation in emergency departments (EDs). GIS technology has been used to clarify the state of COVID-19 at the country level, however, the potential of GIS technology requires ongoing investigation to support Saudi Arabia’s Vision 2030. During a pandemic, great pressure is placed on EDs, with patients waiting long periods for treatment, which can lead to great health risks. This paper aims to illustrate the rule of GIS in providing intelligent solutions in emergency services during the COVID-19 pandemic. A satisfaction questionnaire was distributed to over 180 patients who were selected randomly from the nine emergency rooms of Jeddah governorate hospitals from different priority levels. Fifteen factors are determined and grouped into five domains to reflect patients’ satisfaction: emergency department environment, emergency department staff, physician care satisfaction, and wait time satisfaction. The critical values reveal in wait time were 84% of patients from the second to the fourth level of priority had waited a long or extremely. Most of the respondents (87%) wanted to know ER wait times before arrival hospital. The website was the most preferred choice for publishing wait times outside the ER for 56.7% of them. An online ArcGIS dashboard was developed to monitor hospital wait times in Jeddah City. This dashboard can be useful to the public to guide them in determining which hospital is the most suitable regarding a minimum waiting time and can also help in considering the travel distance. 展开更多
关键词 Emergency Department Waiting time DASHBOARD GIS COVID-19
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Laryngotracheal Stenosis Following Intubation for COVID-19 Pneumonia: A Report of Two Cases
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作者 Derar Al-Domaidat Mohammed Algarni +1 位作者 Ro’a Alshaikh Hasan Hosam Amoodi 《International Journal of Otolaryngology and Head & Neck Surgery》 2022年第5期234-241,共8页
Benign laryngotracheal stenosis (LTS) is a debilitating and potentially life-threatening condition that is commonly caused by iatrogenic events as a result of endotracheal intubation or tracheostomy. Numerous cases ar... Benign laryngotracheal stenosis (LTS) is a debilitating and potentially life-threatening condition that is commonly caused by iatrogenic events as a result of endotracheal intubation or tracheostomy. Numerous cases are being published for patients with coronavirus disease 2019 (COVID-19) who end up with severe LTS after prolonged intubation or tracheostomy. Here, we presented two cases of LTS due to prolonged intubation after severe COVID-19 pneumonia. The characteristic of these two cases is that both of them needed second time intubation and were readmitted because of severe dyspnoea and all the workup for post-COVID-19 complications were investigated except the LTS which was later diagnosed after one month of suffering of these patients. 展开更多
关键词 Subglottic Stenosis Tracheal Stenosis Laryngotracheal Stenosis Prolonged Intubation COVID-19
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