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41.
This study describes for the first time the preparation of re-dispersible surfactant-free dry eicosane oil emulsion using cellulose nanocrystals (CNCs) using the freeze-drying technique. Surface properties of CNCs constitute a critical point for the stability of o/w emulsions and thus can affect both the droplet size and dispersion properties of the emulsion. Therefore, surface modification of CNCs was performed to understand its effect on the size of the obtained re-dispersible dry o/w eicosane emulsion. Decoration of the CNC surface with metal and metal oxide nanoparticles was conducted through the available alcoholic groups of glycosidic units of CNC, which played a dual role in reducing and stabilizing nanoparticles. Of these nanoparticles, silver (AgNPs), gold (AuNPs), copper oxide (CuO-NPs), and iron oxide (Fe3O4-NPs) nanoparticles were prepared via a facile route using alkali activated CNCs. Thorough characterizations pertaining to the as-prepared nanoparticles and their re-dispersible dry eicosane o/w emulsions were investigated using UV-vis spectroscopy, TEM, XRD, particle size, zeta potential, and STEM. Results confirmed the ability of CNCs to stabilize and/or reduce the formed nanoparticles with different sizes and shapes. These nanoparticles showed different shapes and surface charges accompanied by individual morphologies, reflecting on the stability of the re-dispersed dry eicosane emulsions with droplet sizes varying from 1.25 to 0.5 μm.Schematic diagram for the detailed preparation of dry eicosane o/w emulsions. 相似文献
42.
Sequence variants in nine different genes underlying rare skin disorders in 10 consanguineous families 下载免费PDF全文
Khadim Shah MPhil Sabba Mehmood MPhil Abid Jan PhD Izoduwa Abbe MS Raja Hussain Ali PhD Anwar Khan MPhil Muhammad S. Chishti PhD Kwanghyuk Lee MPhil Farooq Ahmad MPhil Muhammad Ansar PhD University of Washington Center for Mendelian Genomics Shaheen Shahzad PhD Deborah A. Nickerson PhD Michael J. Bamshad MD Paul J. Coucke PhD Regie L. P. Santos‐Cortez MD PhD Richard A. Spritz MD Suzanne M. Leal PhD Wasim Ahmad PhD 《International journal of dermatology》2017,56(12):1406-1413
43.
Nonsentinel node metastasis in breast cancer patients: assessment of an existing and a new predictive nomogram 总被引:12,自引:0,他引:12
Degnim AC Reynolds C Pantvaidya G Zakaria S Hoskin T Barnes S Roberts MV Lucas PC Oh K Koker M Sabel MS Newman LA 《American journal of surgery》2005,190(4):543-550
BACKGROUND: The accurate prediction of nonsentinel node (NSN) metastasis in breast cancer patients remains uncertain. METHODS: The medical records of 574 breast cancer patients from 2 different institutions (Mayo Clinic and University of Michigan) with sentinel lymph node biopsy examination and completion axillary lymph node dissection were reviewed for multiple clinicopathologic variables. The Memorial Sloan Kettering Cancer Center nomogram performance for prediction of NSN metastases was assessed. A new model was developed with clinically relevant variables and possible advantages. RESULTS: The Memorial Sloan Kettering Cancer Center nomogram predicted the likelihood of NSN metastasis with an area under the receiver operating characteristic curve of .72 and .86. For predicted probability cut-off points of 5% and 10%, the false-negative rates were 0% and 14% (Mayo), and 17% and 11% (Michigan). A new model was developed with similar area under the curve but lower false-negative rates for low-probability subgroups. CONCLUSIONS: Predictive models for NSN tumor burden are imperfect. 相似文献
44.
Ramakrishna Narra Shaheen Syed Nethula Sowjanya Satyanarayana Veeragandham 《Radiology Case Reports》2022,17(5):1506
Adrenal cortical carcinoma (ACC) is a rare, aggressive endocrine malignancy with a reported incidence of 1.0-2.0 cases per million population and a poor prognosis due to metastatic spread. About 25% of cases of ACC present with metastases at the time of diagnosis. Metastatic spread of ACC commonly involves lungs, liver, kidney, peritoneum, lymph nodes, venous extension to the renal vein or inferior vena cava and bone. We report a case of a 47-year-old male with a nonfunctioning ACC with metastases to skeletal muscle (subscapularis, paraspinal, iliacus and gluteus maximus muscle) in addition to metastasis to the lung, which was not reported in the literature. Unfortunately, the patient expired prior to the surgery due to respiratory distress. 相似文献
45.
Nanosized zeolite Y is used in various applications from catalysis in petroleum refining to nanofillers in water treatment membranes. Ball milling is a potential and fast technique to decrease the particle size of zeolite Y to the nano range. However, this technique is associated with a significant loss of crystallinity. Therefore, in this study, we investigate the effect of adding biodegradable and recyclable cellulose nanofibrils (CNFs) to zeolite Y in a wet ball milling approach. CNFs are added to shield the zeolite Y particles from harsh milling conditions due to their high surface area, mechanical strength, and water gel-like format. Different zeolite Y to CNFs ratios were studied and compared to optimize the ball milling process. The results showed that the optimal zeolite Y to CNFs ratio is 1:1 to produce a median particle size diameter of 100 nm and crystallinity index of 32%. The size reduction process provided accessibility to the zeolite pores and as a result increased their adsorption capacity. The adsorption capacity of ball-milled particles for methylene blue increased to 29.26 mg/g compared to 10.66 mg/g of the pristine Zeolite. These results demonstrate the potential of using CNF in protecting zeolite Y particles and possibly other micro particles during ball milling. 相似文献
46.
Arsenic (As) is considered to be one of the top environmental contaminants of concern worldwide. In many regions in Pakistan, there are reports of increased levels of As in the environment, and this metalloid remains a major source of contamination of soil, water and fodder. This pathway of exposure has emerged as a new threat for both wildlife and the surrounding human communities because of the mobilization and accumulation of As via the food chain. The objective of this critical review is to synthesize historical information about As levels in the environmental resources of Pakistan to better characterize the risk to livestock and humans in the region. The South Punjab and Sindh are the dominant areas which are reported to contain the highest As contamination compared to other regions. This is a concern as millions of animals as well as the human population are facing significant health issues due to As. For example, some of the population of Sindh province are potentially faced with As levels ~10–50?μg/L in drinking water, which is well above safe drinking limits of 10?μg/L outlined by the World Health Organization. These collective data on As are anticipated to be a useful source of information for decisions by the environmental protection agency in Pakistan regarding the adoption of preventive measures against its adverse impacts and toxicity. 相似文献
47.
48.
Eyada TK Farawela HM Khorshied MM Shaheen IA Selim NM Khalifa IA 《Blood coagulation & fibrinolysis》2012,23(1):64-68
Immune thrombocytopenic purpura (ITP) is an acquired autoimmune disorder caused by the production of antiplatelet antibodies. The current case-control study aimed at detecting the frequency of FcγRIIa-131H/R and FcγRIIIa-158F/V genes polymorphism in Egyptian children with ITP as genetic markers for ITP risk, and to clear out their possible role in choosing the treatment protocols of ITP. To achieve this aim, FcγRIIa genotyping was tested by PCR-restriction fragment length polymorphism (RFLP) technique, whereas FcγRIIIa genotyping was tested by nested PCR followed RFLP analysis. The current case-control study was conducted on 92 children with ITP; 12 acute and 80 chronic cases and 90 controls. The V allele and FcγRIIIa FV heterotype were significantly higher in ITP patients and conferred increased ITP risk [odds ratio (OR) = 1.96 and 2.55, respectively]. The frequency of FcγRIIa H allele was significantly higher among chronic ITP patients. In conclusion, FcγRIIIa gene polymorphism may contribute to susceptibility to ITP. Moreover, analysis of the FcγR polymorphisms in ITP patients could influence the effectiveness of medications and selection of the line of treatment. 相似文献
49.
Intravenous administration of an ethanolic extract of Haloxylon recurvum (30–300 μg/kg) caused a rise in arterial blood pressure in normotensive anaesthetized rats. Pretreatment of animals with phentolamine (1 mg/kg) abolished the vasoconstrictor response of the plant extract in a way similar to that of norepinephrine (NE). In an isolated rabbit aorta preparation, both plant extract and NE produced contractile responses which were blocked by phentolamine (0.3 μg/mL). In isolated guinea-pig atria, the plant extract caused positive inotropic and chronotropic responses similar to that of NE and was blocked by propranolol (0.3 μg/mL). These results suggest that vasoconstrictor and cardiac stimulatory effects of the plant extract are mediated through mechanisms similar to those of NE (stimulation of α-adrenergic receptors in the blood vessels and cardiac β-receptors respectively) and hence this plant contains sympathomimetic constituent(s). 相似文献
50.