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71.
P. Chakraborty Banerjee Ren Ping Woo Sam Matthew Grayson Amrita Majumder R. K. Singh Raman 《Materials》2014,7(8):6092-6104
The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution (NaCl). Electrical equivalent circuit (EEC) was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Post corrosion morphologies of the zeolite coated and the uncoated AZ91D alloy were investigated using SEM. The corrosion resistance of the zeolite coated specimen was at least one order of magnitude higher than the uncoated specimen. 相似文献
72.
Chetan P. Huded Samir R. Kapadia Jad A. Ballout Amar Krishnaswamy Stephen G. Ellis Russell Raymond Leslie Cho Conrad Simpfendorfer Chris Bajzer Joseph Martin Ravi Nair A. Michael Lincoff Kathleen Kravitz Venu Menon Scott Hantz Umesh N. Khot 《Catheterization and cardiovascular interventions》2020,96(2):E165-E173
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75.
LaBounty TM Shah M Raman SV Lin FY Berman DS Min JK 《The American journal of cardiology》2012,109(11):1594-1599
Comparative clinical outcomes after exposure to alternate low osmolar contrast media (LOCM) during invasive coronary angiography (ICA) and/or percutaneous coronary intervention (PCI) have been incompletely examined. From a retrospective multicenter observational study, we identified 107,994 adults without previous hemodialysis undergoing ICA and/or PCI with iohexol, iopamidol, or ioversol. We created a propensity score for contrast media type using age, gender, coverage status, route of hospitalization, illness severity, physician specialty, co-morbidities, and procedure type. Propensity matching was performed in a 1:1 fashion for iohexol (n = 10,204) and iopamidol (n = 10,204) and in a 1:1 fashion for iohexol (n = 19,482) and ioversol (n = 19,482). Groups were examined for differences in in-hospital mortality or subsequent hemodialysis, length of stay, and 30-day readmission for contrast-induced nephropathy (CIN). Compared to patients exposed to iohexol, no differences were observed for patients exposed to iopamidol or ioversol for in-hospital hemodialysis (0.5% vs 0.4%, p = 0.45; 0.3% vs 0.5%, p = 0.05), in-hospital mortality (0.7% vs 0.6%, p = 0.60; 0.5% vs 0.6%, p = 0.42), or composite hemodialysis or mortality (1.1% vs 1.0%, p = 0.58; 0.8% vs 1.0%, p = 0.06); for hospital length of stay (2.9 ± 2.7 vs 2.9 ± 2.7 days, p = 0.05; 2.8 ± 2.6 vs 2.9 ± 3.1 days, p = 0.35); or for 30-day readmission for CIN (0.1% vs 0.1%, p = 0.82; 0.1% vs 0.1%, p = 0.52). In conclusion, for patients undergoing ICA and/or PCI exposed to alternate LOCM, in-hospital death, need for hemodialysis, or readmission for CIN are uncommon, with no apparent clinical advantage among LOCM agents. 相似文献
76.
K. Venu Gopal Reddy 《Journal of maxillofacial and oral surgery》2012,11(3):271-275
Objectives
(1) To collect the data related to distribution of third molar impactions among rural population by clinical and radiological examinations. (2) To collect the information on distribution of third molar impactions among urban population by clinical and radiological examinations. (3) To compare the patterns of distribution of third molar impactions among rural and urban residents with respect to type of impaction, arch, gender and age.Method
A cross-sectional study was conducted in Dharwad district of Karnataka state located in South India involving 630 rural and 270 urban subjects as per demographic profile of India. A two stage sampling procedure was adopted in the selection of the sample.Statistical Analysis
Data was analyzed using STATISTICA-6.0. χ2 test was used to explore the association between different variables and third molar impactions. A P ≤ 0.05 was considered statistically significant.Results
14.92% of rural subjects and 27.40% urban subjects were reported to be suffering from third molar impactions.Conclusions
The overall prevalence of third molar impactions among the study subjects was found to be 18.67%. A significant association was noticed between the ‘different arches’ and distribution of third molar impactions in both rural and urban population. Subjects with vertical impactions were found to be most common in both the groups. 相似文献77.
Marwaha RK Tandon N Garg MK Desai A Kanwar R Sastry A Narang A Arora S Bhadra K 《Clinical endocrinology》2012,76(6):905-910
Objective Country‐wide evaluation of thyroid disorders in school children following two decades of universal salt iodization (USI) has not been carried out till date. This study was planned with aim to assess thyroid status of school children two decades after the launch of USI programme. Design Population survey. Patients We collected data from 25 schools in 19 cities across five different geographical zones of India. Those children who were evaluated for anthropometry, and goitre status by palpation formed ‘total population’. Children who consented to give blood samples were defined as ‘study population’. Measurements Serum free T3, free T4, TSH, anti‐TPO antibody and thyroid ultrasound. Results A total of 38 961 children aged 5–15 years formed total population. Goitre rate was 15·5% while thyroid hypoechogenicity was found in 4404 (11·3%) children. In the study population (13 790 children), 2258 (16·4%) had goitre, 505 (3·7%) had positive anti‐TPO antibody titres, 1001 (7·3%) had hypothyroidism (TSH > 5·2 μIU/ml) and 41 (0·3%) had thyrotoxicosis (TSH < 0·1 μIU/ml). Among goitrous children, 203 (9·0%) had anti‐TPO positivity, 365 (16·1%) had hypoechogenicity of thyroid and either of these were present in 488 (21·6%) children. Conclusions Endemic goitre in school children persisted nationwide, despite more than two decades of USI programme. Thyroid autoimmunity only partially explains the increase in goitre prevalence. 相似文献
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Rehana Khan Abhishek Sharma Raghul Ravikumar Avani Parekh Ramyaa Srinivasan Ronnie Jacob George Rajiv Raman 《Investigative ophthalmology & visual science》2021,62(7)
PurposeTo study the association between gut microbial abundance and sight-threatening diabetic retinopathy among patients with a history of type 2 diabetes mellitus.MethodsAn observational case-control study was performed using a sample population of diabetics referred to a tertiary eye institute. Sample subjects were identified as cases if they were diagnosed with sight-threatening diabetic retinopathy and controls if they were not but had at least a 10-year history of diabetes. Fecal swabs for all patients were collected for enumeration and identification of sequenced gut microbes. Statistical analyses were performed to associate the clinically relevant Bacteroidetes to Firmicutes relative abundance ratio (B/F ratio) with sight-threatening diabetic retinopathy and an optimal cutoff value for the ratio was identified using Youden''s J statistics.ResultsA sample size of 58 diabetic patients was selected (37 cases, 21 controls). No statistically significant difference in the relative abundance among the predominant phyla between the groups were found. In our univariate analysis, the B/F ratio was elevated in cases compared to controls (cases, 1.45; controls, 0.94; P = 0.049). However, this statistically significant difference was not seen in our multivariate regression model. Optimal cutoff value of 1.05 for the B/F ratio was identified, and significant clustering of cases above this value was noted in beta diversity plotting.ConclusionsNo difference in gut microbial abundance for any particular phylum was noted between the control and diseased population. Increased gut microbial B/F ratio can be a potential biomarker for the development of sight-threatening diabetic retinopathy among type 2 diabetic patients. 相似文献
80.
Malnutrition is prevalent among cirrhotic patients and is an important prognostic factor. Etiologic factors include hypermetabolism, malabsorption, altered nutrient metabolism, and anorexia. It is a challenge to manage nutrition in cirrhotic patients because of alterations to metabolic and storage functions of the liver; use of traditional assessment tools, such as anthropometric and biometric measures, is difficult because of complications such as ascites and inflammation. In addition to meeting macro- and micronutrient requirements, the composition and timing of supplements have been proposed to affect efficacy of nutrition support. Studies have indicated that branched chain aromatic acid can be given as therapeutic nutrients, and that probiotics and nocturnal feeding improve patient outcomes. 相似文献