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排序方式: 共有909条查询结果,搜索用时 140 毫秒
41.
Hesham R. El-Seedi Rehan M. El-Shabasy Shaden A. M. Khalifa Aamer Saeed Afzal Shah Raza Shah Faiza Jan Iftikhar Mohamed M. Abdel-Daim Abdelfatteh Omri Nahid H. Hajrahand Jamal S. M. Sabir Xiaobo Zou Mohammed F. Halabi Wessam Sarhan Weisheng Guo 《RSC advances》2019,9(42):24539
Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. However, the main methods currently utilized in their production are not environmentally friendly. With the aim of promoting a green approach for the synthesis of NPs, this review describes eco-friendly methods for the preparation of biogenic NPs and the known mechanisms for their biosynthesis. Natural plant extracts contain many different secondary metabolites and biomolecules, including flavonoids, alkaloids, terpenoids, phenolic compounds and enzymes. Secondary metabolites can enable the reduction of metal ions to NPs in eco-friendly one-step synthetic processes. Moreover, the green synthesis of NPs using plant extracts often obviates the need for stabilizing and capping agents and yields biologically active shape- and size-dependent products. Herein, we review the formation of metallic NPs induced by natural extracts and list the plant extracts used in the synthesis of NPs. In addition, the use of bacterial and fungal extracts in the synthesis of NPs is highlighted, and the parameters that influence the rate of particle production, size, and morphology are discussed. Finally, the importance and uniqueness of NP-based products are illustrated, and their commercial applications in various fields are briefly featured.Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. 相似文献
42.
Amir Azarpazhooh Thuan Dao Wendy J. Ungar Faiza Chaudry Rafael Figueiredo Murray Krahn Shimon Friedman 《Journal of endodontics》2014
Introduction
To effectively engage patients in clinical decisions regarding the management of teeth with apical periodontitis (AP), there is a need to explore patients' perspectives on the decision-making process. This study surveyed patients for their preferred level of participation in making treatment decisions for a tooth with AP.Methods
Data were collected through a mail-out survey of 800 University of Toronto Faculty of Dentistry patients, complemented by a convenience sample of 200 patients from 10 community practices. The Control Preferences Scale was used to evaluate the patients' preferences for active, collaborative, or passive participation in treatment decisions for a tooth with AP. Using bivariate and logistic regression analyses, the Gelberg-Andersen Behavioral Model for Vulnerable Populations was applied to the Control Preferences Scale questions to understand the influential factors (P ≤ .05).Results
Among 434 of 1,000 respondents, 44%, 40%, and 16% preferred an active, collaborative, and passive participation, respectively. Logistic regression showed a significant association (P ≤ .025) between participants' higher education and preference for active participation compared with a collaborative role. Also, immigrant status was significantly associated with preference for passive participation (P = .025).Conclusions
The majority of patients valued an active or collaborative participation in deciding treatment for a tooth with AP. This pattern implied a preference for a patient-centered practice mode that emphasizes patient autonomy in decision making. 相似文献43.
Joseph Papiez Mumtaz V Rojiani Amyn M Rojiani 《International journal of clinical and experimental pathology》2014,7(7):4032-4038
Schwannomas or neurilemmoma are benign peripheral nerve sheath tumors, which most frequently occur at the cerebellopontine angle. This morphologic study examines vascular alterations in these tumors, comparing them to other benign spindle cell neoplasms of the nervous system, while correlating these findings with evidence of vascular permeability. Thirty-four nervous system spindle cell neoplasms, sixteen schwannomas, nine fibroblastic/transitional meningiomas and nine peripheral neurofibromas were stained with H&E, Prussian-blue stain, and immunoreacted for factor VIII-related antigen and interstitial albumin. Schwannomas had focal clusters of vascular proliferation including groups of small thin-walled vessels, as well as larger vessels with extensive hyalinization. Neurofibromas and meningiomas almost uniformly had modest numbers of well-defined, thin walled individual vessels. Free hemosiderin and hemosiderin-laden macrophages were frequently identified in schwannomas. Prussian-blue stain for iron revealed focal or fairly widespread positivity in almost all schwannomas, only one meningioma and none of the neurofibromas. Immunoreaction for albumin demonstrated leakage of vascular proteins into the interstitium confirming tumor vessel permeability in schwannomas. Neither neurofibromas nor meningiomas displayed any detectable interstitial albumin. The above findings confirm a degree of reactive proliferation of vessels in schwannoma along with functional deficits in their vascular integrity with permeability to protein and blood. The presence of hyalinized vessels, hemosiderin, both free and within macrophages, and more readily evident Prussian blue staining, may provide an additional diagnostic clue in discriminating between histologically similar spindle cell lesions. The study however raises the possibility that these changes likely precede or facilitate the degenerative ‘ancient change’ seen in some schwannoma. 相似文献
44.
Rachel L. Marsh Sean Kelly Khalid Mumtaz Jessica Kaffenberger 《The Journal of clinical and aesthetic dermatology》2021,14(12):24
ObjectivePsoriasis is associated with hepatic steatosis, fibrosis, and methotrexate-associated liver injury. There is a need for reliable methods to monitor liver disease in psoriasis. Transient elastography (TE) is a validated non-invasive method for assessing hepatic steatosis and fibrosis. Psoriasis-specific TE studies have been limited until recently. Here, we review the utility and limitations of TE to detect and monitor liver disease in the context of psoriasis.MethodsA comprehensive search using OVID, PubMed, and gray literature was conducted (2005–November 2019) to identify studies of TE use in psoriasis for assessment of hepatic steatosis and fibrosis.ResultsFifteen studies met inclusion criteria. A total of 1,536 patients with psoriasis or psoriatic arthritis were represented. TE-detected liver fibrosis is associated with age, diabetes, obesity, and severity of psoriasis. TE successfully evaluates hepatic steatosis and fibrosis. Elastography has a high negative predictive value and specificity in the context of methotrexate-associated liver fibrosis in psoriasis; however, reported associations between abnormal elastography results and cumulative methotrexate dose varied significantly despite methotrexate’s association with hepatotoxicity and fibrosis. The presence of central adiposity is associated with increased TE failure rate.LimitationThe TE studies included in this review date from 2007 to 2019, which could contribute to publication bias, as the technique of TE has improved over this time period.ConclusionTE is a useful and non-invasive modality to detect hepatic steatosis and fibrosis in psoriasis. Dermatologists might consider TE in psoriatic patients and concomitant risk factors for fibrosis with the understanding that failure rates may be higher in patients with central adiposity. 相似文献
45.
At Hines VA Hospital, three out of 38 cardiac transplant patients, who were 9, 10, and 14 mo post-surgery and treated with immunosuppressive drugs, including OKT3 prophylaxis for acute rejection, developed a solitary pulmonary nodule. Fine-needle aspiration biopsy of the nodules in these three patients revealed a hypercellular, monotonous population of large lymphoid cells. These abnormal cells were isolated, with small aggregates occasionally seen. the nuclear membranes were irregular, the chromatin was finely granular, nucleoli were prominent, and mitotic figures were frequently noted. The cells were immunoreactive to leukocyte common antigen and B-lymphocyte. Lambda light chain immunoglobulin was positive in one case, kappa in the second case, and neither light chains in the third patient. By electron microscopy in one case, the cells were large immature lymphoid cells with immunoblastic features. Subsequent tissue studies, complemented by frozen section immunostaining, flow cytometry, and phenotyping, reaffirmed the diagnosis of malignant lymphoma. It appears that OKT3 therapy increases several fold the risk of lymphoma's developing in cardiac transplant patients. Preliminary published reports have also recommended close surveillance of patients receiving OKT3 for early indications of lymphoproliferative disorder and a reevaluation of the risk vs. benefit for the prophylatic use of OKT3. 相似文献
46.
Aamir Razaq Faiza Bibi Xiaoxiao Zheng Raffaello Papadakis Syed Hassan Mujtaba Jafri Hu Li 《Materials》2022,15(3)
In the new era of modern flexible and bendable technology, graphene-based materials have attracted great attention. The excellent electrical, mechanical, and optical properties of graphene as well as the ease of functionalization of its derivates have enabled graphene to become an attractive candidate for the construction of flexible devices. This paper provides a comprehensive review about the most recent progress in the synthesis and applications of graphene-based composites. Composite materials based on graphene, graphene oxide (GO), and reduced graphene oxide (rGO), as well as conducting polymers, metal matrices, carbon–carbon matrices, and natural fibers have potential application in energy-harvesting systems, clean-energy storage devices, and wearable and portable electronics owing to their superior mechanical strength, conductivity, and extraordinary thermal stability. Additionally, the difficulties and challenges in the current development of graphene are summarized and indicated. This review provides a comprehensive and useful database for further innovation of graphene-based composite materials. 相似文献
47.
48.
Hafsah Akhtar Faiza Bukhari Misbah Nazir Muhammad Nabeel Anwar Adeeb Shahzad 《神经科学通报》2016,32(1):115-126
Depression is the most prevalent debilitating mental illness; it is characterized as a disorder of mood, cognitive function, and neurovegetative function. About one in ten individuals experience depression at some stage of their lives. Antidepressant drugs are used to reduce the symptoms but relapse occurs in ~20% of patients. However, alternate therapies like brain stimulation techniques have shown promising results in this regard. This review covers the brain stimulation techniques electroconvulsive therapy, transcranial direct current stimulation, repetitive transcranial magnetic stimulation, vagus nerve stimulation, and deep brain stimulation, which are used as alternatives to antidepressant drugs, and elucidates their research and clinical outcomes. 相似文献
49.
50.
Mariam Siala Nadia Mahfoudh Radhouane Gdoura Mohamed Younes Hela Fourati Arwa Kammoun Ilhem Chour Nihel Meddeb Lilia Gaddour Faiza Hakim Sofien Baklouti Naceur Bargaoui Sleheddine Sellami Adnene Hammami Hafedh Makni 《Rheumatology international》2009,29(10):1193-1196
The purpose of the present study is to investigate the frequency of HLA-B27 and its alleles in reactive arthritis (ReA) and
in ankylosing spondylitis (AS) in Tunisia. HLA-B27 alleles were typed by PCR amplification with sequence-specific primers.
We studied 17 patients with ReA associated with urethritis or with gastrointestinal infection; 42 HLA-B27-positive patients
with AS and 100 healthy controls. Eleven ReA patients (67.7%) were HLA-B27 positive. There was an increased frequencies of
HLA-B27 (P = 7.76 × 10−12, OR = 59.30) and a moderate increase of HLA-B51 (P = 0.015; OR = 4.91) alleles in ReA patients when compared with healthy controls. Four B27 subtypes were identified: B*2702,
05, 09 and B*2712. The distribution of these alleles in the ReA patients was 37.5% for B*2702 and B*2705. Only these two subtypes
were detected in 18 (42.8%) and 24 (57.1%), respectively, of the AS patients. B*2709 and B*2712 were relatively rare in ReA
patients and were identified in one case each. Our results showed a restricted number of HLA-B27 subtypes associated with
ReA and AS. B*2702 and 2705 were common in ReA and AS patients. 相似文献