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101.
In the present study, the effects of metallic doping on the photoelectron\chemical properties of zinc oxide thin films have been studied. All films have been deposited using the spray pyrolysis technique at a constant doping level of 3 wt% whereby Cu, Ni, and Pb were used as dopants. The structure of all films was studied by X-ray diffraction which showed the grain size of all doped films to be 50 nm. The energy band gap of all films was estimated using optical transmission spectroscopy. The Ni, Cu, and Pb-doped ZnO photoelectrodes were applied for the photoelectrochemical (PEC) H2 generation from H2O. Pb doping leads to the highest photocurrent of the ZnO photoelectrodes. The current density–potential characteristics were measured under white light and monochromatic illumination. The stability of the electrode was quantified as a function of the number of H2 production runs and exposure time. Finally, the incident photon-to-current conversion efficiency, IPCE, and applied bias photon-to-current efficiency, ABPE, were calculated. The optimum IPCE at 390 nm was ∼30% whereas the ABPE was 0.636 at 0.5 V.In the present study, the effects of metallic doping on the photoelectron\chemical properties of zinc oxide thin films have been studied. 相似文献
102.
Jiadi Luo Lingjiao Chen Qiuyuan Wen Lina Xu Shuzhou Chu Weiyuan Wang Mohannad Ma Alnemah Songqing Fan 《International journal of clinical and experimental pathology》2015,8(8):9693-9697
Adrenal lipoadenoma is an extremely rare tumor. Only four cases have been reported so far. The authors reported a case of adrenal lipoadenoma in a 46-year-old man with the history of abdominal pain. The present case, manifesting as a nonfunctional adrenal tumor, is characteristically comprised of a mixture of mature adipocytes and adrenocortical cells. We also reviewed this tumor in different organs which have been published in the literature. 相似文献
103.
Sulieman Al-Johany Hamad A. Al Zoman Mohannad Al Juhaini Mohannad Al Refeai 《Saudi Dental Journal》2010,22(4):183-188
Aim
The purpose of this survey was to assess the level, sources, and need for information about dental implants among a selected sample of dental patients in Riyadh, Saudi Arabia.Materials and methods
Patients’ knowledge and awareness in using dental implants as an option in replacing missing teeth were evaluated through a standardized self- explanatory questionnaire distributed in two places in Riyadh: Military Hospital and College of Dentistry, King Saud University (Darraiyah campus). The questionnaires were handed to the patients during their regular dental visits. A total of 379 subjects were included in this survey.Results
The results of this study indicate that 66.4% of the subjects knew about dental implants. The subjects’ friends and their relatives were the main source of information about dental implants for 31.5% of the subjects, and dentists were the secondary source for 28.3% of the sample. About 82.4% of the subjects need more information about dental implants and 85.2% of them chose the dentist to be the desired source for such information, followed by the internet in 28.5% of the cases. Almost 74.4% of those surveyed did not know if their regular dentists use dental implants. High cost was the major factor in preventing patients from choosing implants in 86.5% of the cases while the long treatment time and fear of surgery was the factor in 71% and 68.6% of the subjects, respectively.Conclusion
The results of this survey showed an acceptable level of awareness about dental implants among a selected sample of dental patients in Riyadh. It also showed the need for providing more general and accurate information to the patients about this treatment modality. 相似文献104.
The association of retinitis pigmentosa with renal disease is rare and occurs mainly in two conditions: medullary cystic disease and Bardet-Biedl syndrome; here we describe a case of retinitis pigmentosa with familial focal segmental glomerulosclerosis, which to the best of our knowledge has never been reported previously. 相似文献
105.
Al Shamsi M Al Samri MT Al-Salam S Conca W Shaban S Benedict S Tariq S Biradar AV Penefsky HS Asefa T Souid AK 《Chemical research in toxicology》2010,23(11):1796-1805
A novel in vitro system was developed to investigate the effects of two forms of calcined mesoporous silica particles (MCM41-cal and SBA15-cal) on cellular respiration of mouse tissues. O(2) consumption by lung, liver, kidney, spleen, and pancreatic tissues was unaffected by exposure to 200 μg/mL MCM41-cal or SBA15-cal for several hours. Normal tissue histology was confirmed by light microscopy. Intracellular accumulation of the particles in the studied tissues was evident by electron microscopy. The results show reasonable in vitro biocompatibility of the mesoporous silicas with murine tissue bioenergetics. 相似文献
106.
107.
Thyroid ophthalmopathy is a common autoimmune, inflammatory disease involving the orbit. Diagnosis is based on the clinical presentation and findings. Imaging, mainly CT and MR imaging, are helpful to reveal the extent of disease and degree of muscle enlargement and to evaluate for complications, such as optic nerve compression. This article reviews the basic pathology and pathophysiology of the disease and describes the extensive imaging findings on CT and MR imaging. The differential diagnosis of thyroid ophthalmopathy is reviewed. 相似文献
108.
Parmar HA Ibrahim M Castillo M Mukherji SK 《Journal of computer assisted tomography》2007,31(3):329-334
In this pictorial review, we present diverse imaging features of spinal schwannomas with an idea to familiarize spine imagers with the varied spectrum of presentation of these tumors. Different types of spinal schwannomas presented include multiple schwannoma (n = 3), schwannoma with cystic degeneration (n = 3), schwannoma with hemorrhage (n = 2), melanotic schwannoma (n = 1), intraosseous schwannoma (n = 2), schwannoma growing into the foramen transversarium (n = 1), intramedullary schwannoma (n = 1), large or giant schwannoma (n = 1), malignant schwannoma (n = 2), and infarcted schwannoma (n = 1). We present imaging findings in these cases and review their differential diagnosis. Awareness of the uncommon presentations of these seemingly common tumors is important in offering a correct diagnosis. 相似文献
109.
Growth differentiation factor 15 (GDF15), a transforming growth factor (TGF)-β superfamily member, has been cloned from a placenta cDNA library as a gene product that has promoted activation of pro-matrix metalloproteinase (MMP)2 mediated by membrane type (MT)1-MMP. Expression of MT1-MMP in HEK293T cells caused cleavage of the GDF15 mature form at N252 –M253 to produce a 6-kDa C -terminal fragment. Treatment of MCF7 cells with GDF15 induced activation of p53 and enhanced expression of p21, which was abrogated by MT1-MMP expression. GDF15 mRNA synthesis was also shown to be induced by treatment of cells with GDF15. Treatment of MCF7 cells with GDF15 caused suppression of cell proliferation. However, proliferation of MCF7 cells transfected with the MT1-MMP gene was not affected by GDF15 treatment, but was suppressed in the presence of the MMP inhibitor BB94. HT1080 cells transfected with the GDF15 gene, which endogenously express MT1-MMP, synthesize a high-level GDF15 precursor form and a low-level mature form, and treatment of cells with BB94 enhanced production of the GDF15 mature form. Consistent with GDF15 production, HT1080 cells transfected with the GDF15 gene proliferated almost equally with control cells, and addition of BB94 effectively suppressed growth of HT1080 cells transfected with the GDF15 gene concomitant with the accumulation of the GDF15 mature form, but not control cells. These results suggest that MT1-MMP contributes to tumor cell proliferation through the cleavage of GDF15, which down-regulates cell proliferation by inducing activation of p53 and p21 synthesis. ( Cancer Sci 2007; 98: 1330–1335) 相似文献
110.
Mohannad Alharbi Ahmad Almarzouq Armand Zini 《Canadian Urological Association journal》2021,15(5):E272
IntroductionSeveral studies addressed the role of testicular sperm aspiration with intracytoplasmic sperm injection (ICSI) in azoospermic men, but few have included non-azoospermic men. The aim of this study was to evaluate testicular sperm aspiration (TESA) sperm retrieval rates and ICSI outcomes in men with severe oligozoospermia.MethodsData were collected retrospectively from 88 consecutive, non-azoospermic, infertile men with idiopathic severe oligozoospermia who underwent TESA between January 2011 and January 2018. Patients were categorized into four groups according to sperm concentration: <5 and >1 million/ml (group 1), <1 and > 0.1 million/ml (group 2), <0.1 million/ml (group 3), and cryptozoospermia (group 4).ResultsMean male age was 37±7 years and the mean female age was 33±4 years. Sperm was recovered successfully in 90% (79/88) of the men overall and in 100% (30/30) of the men in group 1, 97% (29/30) of the men in group 2, 88% (15/17) of the men in group 3, and 45% (5/11) of the men in group 4. Most (65%, 57/88) of the couples had an embryo transfer (ET). The overall clinical pregnancy rate per ET was 46% (26/57). The clinical pregnancy rates (per ET) were 43% (9/21) in group 1, 65% (13/20) in group 2, 36% (4/11) in group 3, and 0% (0/5) in group 4.ConclusionsOur data indicate TESA allows for high sperm retrieval rates and acceptable ICSI pregnancy rates in men with severe oligozoospermia. However, in our experience, TESA sperm retrieval rates and ICSI outcomes are poor in cryptozoospermic men. 相似文献