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71.
Abdellah Bouchendouka Zine El Abiddine Fellah Zakaria Larbi Zineeddine Louna Erick Ogam Mohamed Fellah Claude Depollier 《Materials》2022,15(10)
The fully developed laminar flow of a viscous non-Newtonian fluid in a rough-walled pipe is considered. The fluid rheology is described by the power–law model (covering shear thinning, Newtonian, and shear thickening fluids). The rough surface of the pipe is considered to be fractal, and the surface roughness is measured using surface fractal dimensions. The main focus of this study lies in the theoretical investigation of the influence of the pipe surface roughness on the velocity profile and the Darcy friction factor of an incompressible non-Newtonian fluid. The plotted results demonstrate that shear thinning fluids are the most sensitive to the surface roughness compared with Newtonian and shear thickening fluids. For a particular value of the surface fractal dimension, there exists an intersection point where shear thinning, Newtonian, and shear thickening fluids behave the same way regarding the amplitude of the velocity profile and the friction factor. This approach has a variety of potential applications, for instance fluid dynamics in hydrology, blood flow in the cardiovascular system, and many industrial applications. 相似文献
72.
73.
Maen Abdelrahim Hadeel Al-Rawi Abdullah Esmail Jiaqiong Xu Godsfavour Umoru Fahad Ibnshamsah Ala Abudayyeh David Victor Ashish Saharia Robert McMillan Ebtesam Al Najjar Doaa Bugazia Maryam Al-Rawi Rafik M. Ghobrial 《Current oncology (Toronto, Ont.)》2022,29(5):3585
Background: The management of cholangiocarcinoma is continually reviewed on a current evidence basis to develop practice guidelines and consensus statements. However, the standardized treatment guidelines are still unclear for cholangiocarcinoma patients who are listed for liver transplantation. We aimed to validate and evaluate the potential efficacy of chemotherapy combination of Gemcitabine and Cisplatin as a neo-adjuvant treatment for cholangiocarcinoma patients before liver transplantation. Methods: In this prospective case series, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with a combination of neoadjuvant gemcitabine and cisplatin with no radiation. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center according to an open-labeled, and center-approved clinical management protocol. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. Results: Between 1 March 2016, and 15 March 2022, 10 patients (8 males and 2 females) with a median age of 62.71(interquartile range: 60.02–71.87) had a confirmed diagnosis of intrahepatic or hilar cholangiocarcinoma and underwent liver transplantation. Median days of neoadjuvant therapy for a given combination of gemcitabine and cisplatin were 181 (IRQ: 120–250). Nine patients (90%) were reported with no recurrence or metastasis, and only 1 patient had confirmed metastasis (10%); days for metastasis after transplantation were 612 for this patient. All patients received a combination of gemcitabine and cisplatin as neo-adjuvant while awaiting liver transplantation. The median days of follow-up were 851 (813–967). Overall survival was 100% (95% CI 100–100%) at both years one and two; 75% (95% CI 13–96%) at years three to five. One patient died at eight hundred and eighty-five days. No adverse events were reported after liver transplantation including the patient who was confirmed with recurrence. Conclusions: Our finding demonstrated that neo-adjuvant gemcitabine and cisplatin with no radiation prior to liver transplantation resulted in excellent outcomes for patients with cholangiocarcinoma. 相似文献
74.
Jason Doran Nabil Seyidov Samir Mehdiyev Giorgia Gon Esther Kissling Trent Herdman Javahir Suleymanova Ana Paula Couthino Rehse Richard Pebody Mark A. Katz Gahraman Hagverdiyev 《Influenza and other respiratory viruses》2022,16(4):626
IntroductionWe evaluated uptake and factors associated with COVID‐19 vaccination among health workers (HWs) in Azerbaijan.ResultsAmong 1575 HWs, 73% had received at least one dose, and 67% received two doses; all received CoronaVac. Factors associated with vaccination uptake included no previous COVID‐19 infection, older age, belief in the vaccine''s safety, previous vaccination for influenza, having patient‐facing roles and good or excellent health by self‐assessment.ConclusionThese findings could inform strategies to increase vaccination uptake as the campaign continues. 相似文献
75.
Augmentation pharyngoplasty, in which tissue filler or grafts are used to augment the posterior nasopharynx, is an accepted option to treat velopharyngeal insufficiency. It is generally well tolerated and safe with limited side effects. In this study, we describe a case of a retropharyngeal abscess and Grisel syndrome following hyaluronic acid augmentation pharyngoplasty. Grisel syndrome is a serious condition that requires early diagnosis and prompt intervention to prevent further complications. 相似文献
76.
Nils Beisemann Eric Mandelka Jan S. El Barbari Bjrn Kreher Sven Y. Vetter Paul Alfred Grützner Jochen Franke 《Journal of digital imaging》2022,35(3):514
Previous studies have demonstrated a frequent occurrence of screw/K-wire malpositioning during surgical fracture treatment under 2D fluoroscopy and a correspondingly high revision rate as a result of using intraoperative 3D imaging. In order to facilitate and accelerate the diagnosis of implant malpositioning in 3D data sets, this study investigates two versions of an implant detection software for mobile 3D C-arms in terms of their detection performance based on comparison with manual evaluation. The 3D data sets of patients who had received surgical fracture treatment at five anatomical regions were extracted from the research database. First, manual evaluation of the data sets was performed, and the number of implanted implants was assessed. For 25 data sets, the time required by four investigators to adjust each implant was monitored. Subsequently, the evaluation was performed using both software versions based on the following detection parameters: true-positive-rate, false-negative-rate, false-detection-rate and positive predictive value. Furthermore, the causes of false positive and false negative detected implants depending on the anatomical region were investigated. Two hundred fourteen data sets with overall 1767 implants were included. The detection parameters were significantly improved (p<.001) from version 1 to version 2 of the implant detection software. Automatic evaluation required an average of 4.1±0.4 s while manual evaluation was completed in 136.15±72.9 s (p<.001), with a statistically significant difference between experienced and inexperienced users (p=.005). In summary, version 2 of the implant detection software achieved significantly better results. The time saved by using the software could contribute to optimizing the intraoperative workflow. 相似文献
77.
Zuhier A. Awan Shareefa A. AlGhamdi Nabil A. Alhakamy Solomon Z. Okbazghi Mohamed A. Alfaleh Shaimaa M. Badr-Eldin Hibah M. Aldawsari Mohammed A. S. Abourehab Hani Z. Asfour Shadi A. Zakai Mohammad W. Alrabia Aya A. Negm Mohamed A. El-Moselhy Sara S. Sharkawi Waleed Y. Rizg 《Drug delivery》2022,29(1):1536
Certain anticancer agents selectively target the nucleus of cancer cells. One such drug is 2-methoxyestradiol (2ME), which is used for treating lung cancer. To improve the therapeutic effectiveness of these agents, many new methods have been devised. 2ME was entrapped into the core of hydrophobic invasomes (INVA) covered with Phospholipon 90G and apamin (APA). The Box–Behnken statistical design was implemented to enhance the composition. Using Design-Expert software (Stat-Ease Inc., Minneapolis, MN), the INVA component quantities were optimized to obtain spherical particles with the smallest size, that is, a diameter of 167.8 nm. 2ME-INVA-APA significantly inhibited A549 cells and exhibited IC50 of 1.15 ± 0.04 µg/mL, which is lower than raw 2ME (IC50 5.6 ± 0.2 µg/mL). Post 2ME-INVA-APA administration, a significant rise in cell death and necrosis was seen among the A549 cells compared to those treated with plain formula or 2ME alone. This effect was indicated by increased Bax expression and reduced Bcl-2 expression, as well as mitochondrial membrane potential loss. Moreover, the cell cycle analysis showed that 2ME-INVA-APA arrests the G2-M phase of the A549 cells. Additionally, it was observed that the micellar formulation of the drug increased the cell count in pre-G1, thereby exhibiting phenomenal apoptotic potential. Furthermore, it up-regulates caspase-9 and p53 and downregulates TNF-α and NF-κβ. Collectively, these findings showed that our optimized 2ME-INVA-APA could easily seep through the cell membrane and induce apoptosis in relatively low doses. 相似文献
78.
Meriem Haloua Nizar El Bouardi Badre Eddine Alami Youssef Alaoui Lamrani Mustapha Maaroufi Hinde El Fatemi Mohammed Ridal Meryeme Boubbou 《Radiology Case Reports》2022,17(8):2607
Hemangioma of the facial sinuses is a rare pathology, and given the lack of clinical specificity, the differential diagnosis with a malignant lesion often arises. We report the case of a 32-year-old patient who consulted for recurrent epistaxis of moderate severity. The preoperative diagnosis of a hemangioma of the left maxillary sinus was based on computed tomography and magnetic resonance imaging data, confirmed by the anatomopathological study of the surgical specimen, preceded by an embolization that facilitated the endoscopic surgical excision. 相似文献
79.
Monika Maria Biernat Jolanta Rusiecka-Ziółkowska Elżbieta Piątkowska Iwona Helemejko Paweł Biernat Grażyna Gościniak 《Japanese journal of ophthalmology》2018,62(6):628-633
Purpose
Two Demodex species (eyelash mites)—D. folliculorum and D brevis—are believed to be associated with human skin and eye diseases. However, the clinical significance of infection with Demodex species remains controversial.Study design
The aim of this study was to estimate the prevalence of ocular demodicosis in patients with blepharitis as compared with the prevalence in the healthy population in Poland.Methods
This case-control prospective study was carried out from 2007 to 2016. The enrolled patients (668) were divided into 2 groups: the study group, comprising 553 patients with blepharitis (349 women and 204 men, aged 17–88 years), and the control group, comprising 115 healthy volunteers without a history of ocular pathologies (78 women and 37 men, aged 17–88 years). A sample of 10 eyelashes was taken aseptically from each eye of the examined person and later studied under a light microscope.Results
Demodex species were found in 62.4% (345/544) of the patients in the study group and in 24.3% (28/100) of the controls (P = .001, OR = 0.006). The overall prevalence was 55.8% (373/668) in all the examined participants. The presence of Demodex infection increased with age in both groups. No association of Demodex infection with gender was found (119/204 vs 226/349; P > .05, OR 1.086). A high mean number of mites was present more frequently in patients aged older than 50 years and in those who complained especially about itching (P < .05).Conclusion
The prevalence of ocular demodicosis is significantly correlated with blepharitis and increases with age.80.
The eye is an invulnerable organ with intrinsic anatomical and physiological barriers, hindering the development of a pioneer ocular formulation. The aim of this work was to develop an efficient ocular delivery system that can augment the ocular bioavailability of the antifungal drug, terconazole. Mesoporous silica microparticles, Syloid® 244 FP were utilized as the carrier system for terconazole. Preliminary studies were carried out using different drug:Syloid® weight ratios. The optimum weight ratio was mixed with various concentrations (30 and 60%w/w) of poly (lactic-co-glycolic acid) (PLGA), ester or acid-capped and with different monomers-ratio (50:50 and 75:25) using the nano-spray dryer. Results revealed the superiority of drug:Syloid® weight ratio of 1:2 in terms of yield percentage (Y%), SPAN and drug content percentage (DC%). Furthermore, incorporation of PLGA with lower glycolic acid monomer-ratio significantly increased Y%. In contrast, increasing the glycolic acid monomer-ratio resulted in higher DC% and release efficiency percentage (RE%). Additionally, doubling PLGA concentration significantly reduced Y%, DC%, drug loading percentage (DL%) and RE%. Applying desirability function in terms of increasing DC%, DL% besides RE% and decreasing SPAN, the selected formulation was chosen for DSC, XRD and SEM investigations. Results confirmed the successful loading of amorphized terconazole on PLGA-modified Syloid® microparticles. Moreover, pharmacokinetic studies for the chosen formulation on male Albino rabbits’ eyes revealed a 2, 6.7 and 25.3-fold increase in mean residence time, Cmax and AUC0–24-values, respectively, compared to the drug suspension. PLGA-modified Syloid® microparticles represent a potential option to augment the bioavailability of ocular drugs. 相似文献