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排序方式: 共有1113条查询结果,搜索用时 31 毫秒
1.
Edel A. O'Toole MRCPI Patrick Deasy FRCPI † Rosemarie Watson FRCPI FACP 《Pediatric dermatology》1995,12(4):348-350
Abstract: We report a patient with cutis marmorata telangiectatica with the hitherto unreported anomaly of a double aortic arch. The presence of two major vascular anomalies in this patient may be secondary to a developmental defect of the mesoderm during embryogenesis. 相似文献
2.
Mathematical Models for Predicting the Epidemiologic and Economic Impact of Vaccination against Human Papillomavirus Infection and Disease 总被引:2,自引:1,他引:1
Infection with human papillomavirus (HPV) is the primary causeof cervical cancer, other anogenital cancers, genital warts,and recurrent respiratory papillomatosis. Clinical studies havedemonstrated that a prophylactic HPV vaccine can prevent infection,genital warts, and the precancerous lesions that lead to cervicalcancer. Given the absence of data on the long-term effectivenessof HPV vaccination, a number of mathematical models have beendeveloped to provide insight to policy makers by projectingthe long-term epidemiologic and economic consequences of vaccinationand evaluate alternative vaccination policies. This paper reviewsthe state of these models. Three types of HPV mathematical modelshave been reported in the literature: cohort, population dynamic,and hybrid. All have demonstrated that vaccination can significantlyreduce the incidence of cervical cancer in the long term. However,only the cohort and hybrid models have evaluated the cost-effectivenessof vaccination strategies for preventing cervical cancer. Thesemodels have generally shown that vaccinating females can becost-effective. None has accounted for the potential benefitsof vaccinating the population to reduce the burden of recurrentrespiratory papillomatosis and cancers of the vagina, vulva,anus, penis, and head/neck. Given that only the population dynamicmodel can account for both the direct and indirect (i.e., herdimmunity effects) benefits of vaccination in the population,future research should focus on further development of dynamicmodels by expanding the range of epidemiologic outcomes trackedand including the ability to assess the cost-effectiveness ofalternative vaccination policies. cost-benefit analysis economics papillomavirus, human vaccines 相似文献
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4.
S R Adair D Elamin S Tharmaratnam 《The journal of maternal-fetal & neonatal medicine》2004,15(4):275-278
Placenta increta, a rare complication of pregnancy, is associated with significant postpartum hemorrhage often requiring emergency hysterectomy. We report a case of conservative management, with a combination of parenteral methotrexate, serial ultrasound and Doppler assessment, followed by interval manual removal of placenta. 相似文献
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Kazuya Takeda Shuhei Sakakibara Kazuo Yamashita Daisuke Motooka Shota Nakamura Marwa Ali El Hussien Jun Katayama Yohei Maeda Masanobu Nakata Shigeyuki Hamada Daron M. Standley Masaki Hayama Takashi Shikina Hidenori Inohara Hitoshi Kikutani 《The Journal of allergy and clinical immunology》2019,143(3):1163-1175.e15
7.
In this study, undoped and (Erbium, Ytterbium) co-doped ZnO nanopowders were prepared using the sol-gel method and the supercritical drying of ethyl alcohol. Doping ZnO nanopowders were elaborated with 5 mol% of Er (5 Er: ZnO), 5 mol% of Er and 5 mol% of Yb (5 Er, 5 Yb: ZnO), and 5 mol% of Er and 10 mol% of Yb (5 Er, 10 Yb: ZnO) concentrations. The effects of the Yb concentration on the structural, morphological, photoluminescent, and electrical properties of the ZnO nanopowders were investigated. The main findings of this work were the crystallinization of all of the nanopowders in a hexagonal Wurtzite structure with a spheroidal morphology and a size of 60 nm. Hence, the doping concentration would affect the crystallinity and the morphology of the ZnO nanopowder. The UC (Up-Conversion) emissions were investigated under a 980 nm excitation. It was observed that (Er, Yb: ZnO) exhibited green, ranging between 525 nm and 550 nm and red up-converted emissions of 655 nm, due to the efficient energy transfer process between Er3+ and Yb3+. The absolute quantum yield percentage (QY %) of the doped nanopowders was measured as a function of power density at each up-converted emission. This would prove that (5 Er, 5 Yb: ZnO) had the highest QY percentage value of 6.31 ± 0.2% at a power density of 15.7 W/cm2. Additionally, it had the highest excited state lifetime for green and red emissions. Moreover, the Hall effect measures showed that the resistivity decreased while the electron mobility increased after doping, suggesting that most of rare earth ions were located in the interstitial positions. The carrier concentration increased after doping until (5 Er, 5 Yb: ZnO), suggesting that the Zn2+ ions substituted the RE3+ ions. Then, the carrier concentration decreased, suggesting that doping with higher concentrations would cause grain boundary defects. These findings would suggest that (5 Er, 5 Yb: ZnO) would have the best electrical properties and the lowest band gap energy (3.24 eV). Therefore, the presented preparation of the (Er, Yb: ZnO) nanopowders elaborated, using the sol-gel process would be a potential interesting material for UC applications. 相似文献
8.
Marwa A. M. Abdel-Razek Miada F. Abdelwahab Usama Ramadan Abdelmohsen Ashraf N. E. Hamed 《RSC advances》2022,12(54):35103
Corchorus olitorius L. is a nutritious green leafy vegetable that is eaten as a viscous soup in African and Middle Eastern cultures. The purpose of this review is to highlight the nutritional and nutraceutical potential of this plant. The leaves of C. olitorius are rich providers of minerals as calcium and iron in addition to vitamins B1, B2, folic acid C and E. The leaves contain numerous compounds having several biological effects including antidiabetic and antioxidant properties. Besides, the leaves comprise other phytochemicals such as cardiac glycosides, terpenes, flavonoids, fatty acids, hydrocarbons and phenolics. Various extracts of C. olitorius were shown to exhibit antioxidant, anti-inflammatory, hepatoprotective, antihyperlipidemic, immunostimulant, antitumor, antimicrobial, antidiabetic, analgesic, wound-healing properties and cardioprotective activities. Corchorus olitorius L. is a nutritious green leafy vegetable that is eaten as a viscous soup in African and Middle Eastern cultures. 相似文献
9.
Faisal K. Algethami Khaled Trabelsi Anouar Hajjaji Mohamed B. Rabha Lotfi Khezami Mohamed R. Elamin Brahim Bessais My Ali El Khakani 《Materials》2022,15(14)
The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters. 相似文献
10.
Could Argyrophilic Nucleolar Organizer Regions count mirror DNA Ploidy in Malignant Salivary Gland Tumors?
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Marwa T HussienManar Ali MohamedShima Gafar MansorDoaa F TemerikSherif Farouk ElgayarEnas Alaa El-din Abd El-Aziz 《Asian Pacific journal of cancer prevention》2022,23(6):1983-1992
Objective: Nucleolar organizer regions (NORs) are DNA coils that transcribe to ribosomal RNA. The NOR-associated protein, termed argyrophilic NOR (AgNOR), was visible within the nucleus by staining with silver nitrate examination via the light microscope. AgNOR counting is a proliferation marker and may help in the diagnosis and prognosis of various neoplastic lesions. Aneuploidy (abnormal DNA content) can predict the progression, survival and prognosis of the tumors. The aim of this study was to evaluate the role of AgNORs, DNA ploidy status, and total S-phase fraction (TSPF) as prognostic parameters in malignant salivary gland tumors (MSGTs). Methods: The current study is a retrospective study on a cohort of MSGTs (N=47), to assess AgNORs using Silver Nitrate stain, DNA index (DI), and TSPF using flow cytometry (FCM). Data including tumor size and site, lymphovascular invasion (LVI), lymph node metastasis (LNM) were collected. Results: The AgNORs count was statistically significant with MSGT type. DI was found to have a significant association with tumor site, tumor size and MSGT type. In addition, TSPF was found to be significantly associated with LVI. A moderate positive correlation was noted between AgNORs count and TSPF. LNM, tumor site, high AgNORs and low DI were all associated with short disease-free survival (DFS) and poor overall survival (OS). Conclusion: The present study revealed that high AgNORs count, DNA aneuploidy and TSPF had a poor influence on MSGTs prognosis. 相似文献