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排序方式: 共有1871条查询结果,搜索用时 15 毫秒
31.
Vijay Kumar Rajeev Kumar Gupta Ravi Kumar Gundampati Devendra Kumar Singh Sweta Mohan Syed Hadi Hasan Manisha Malviya 《RSC advances》2018,8(2):619
The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). 相似文献
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33.
Hooman Bahrami-Motlagh Babak Salevatipour Hossein Hassanian-Moghaddam Seyyed Hadi Mirhashemi 《Clinical toxicology (Philadelphia, Pa.)》2018,56(5):348-354
Purpose: Detection of body stuffers is challenging in emergency departments. Because of the small size of baggies, plain radiograph is of little value in most suspects. On the other hand, abdomen CT scan is burdened by high cost and radiation dose. This study was performed to compare the image quality, radiation dose and accuracy of low-dose CT scan in comparison with standard dose.Material and methods: In this prospective study, suspected body stuffers who were referred to the radiology department underwent two different protocols of abdominal non-contrast CT scan simultaneously: low-dose (with equivalent dose to conventional abdominal x-ray) and standard dose. Standard dose CT scan was considered as the reference. Low-dose CT scans were evaluated for detection of baggies by two radiologists blinded to the result of standard dose CT. Image quality, noise, dose-length product (DLP) and effective dose (ED) compared between two groups.Results: The study consisted of 40 patients (33.38?±?7.4 years). Standard dose CT evaluation was positive in 22 patients (55%). In comparison with standard dose CT scan, low-dose group had a sensitivity of 86%, specificity of 100%, PPV and NPV of 100% and 86%. The accuracy of low-dose CT scan for detection of baggies larger than 1?cm was 100%. However, from the 3 cases that could not be detected with low dose protocol, one had CT features suspected for baggies rupture which was intubated and later deceased. Noise average of low-dose protocol, was approximately 7 times greater than standard dose group, while DLP and ED were 9.7 times less.Conclusion: Low dose CT scan appears to be an appropriate screening method for body stuffers, especially when the baggies are larger than one centimeter. However, in the presence of severe clinical symptoms, a standard dose CT scan will be more helpful due to better image quality especially in suspected ruptured baggies. 相似文献
34.
Brian E. Dixon Jamie Pina Hadi Kharrazi Fardad Gharghabi Janise Richards 《Online Journal of Public Health Informatics》2015,7(2)
Objective: To categorize and describe the public health informatics (PHI) and
global health informatics (GHI) literature between 2012 and 2014.Methods: We conducted a semi-systematic review of articles published between
January 2012 and September 2014 where information and communications
technologies (ICT) was a primary subject of the study or a main component of the
study methodology. Additional inclusion and exclusion criteria were used to
filter PHI and GHI articles from the larger biomedical informatics domain.
Articles were identified using MEDLINE as well as personal bibliographies from
members of the American Medical Informatics Association PHI and GHI working
groups.Results: A total of 85 PHI articles and 282 GHI articles were identified. While
systems in PHI continue to support surveillance activities, we identified a
shift towards support for prevention, environmental health, and public health
care services. Furthermore, articles from the U.S. reveal a shift towards PHI
applications at state and local levels. GHI articles focused on telemedicine,
mHealth and eHealth applications. The development of adequate
infrastructure to support ICT remains a challenge, although we identified a
small but growing set of articles that measure the impact of ICT on clinical
outcomes.Discussion: There is evidence of growth with respect to both implementation of
information systems within the public health enterprise as well as a widening of
scope within each informatics discipline. Yet the articles also illuminate the
need for more primary research studies on what works and what does not as both
searches yielded small numbers of primary, empirical articles.Conclusion: While the body of knowledge around PHI and GHI continues to mature,
additional studies of higher quality are needed to generate the robust evidence
base needed to support continued investment in ICT by governmental health
agencies. 相似文献
35.
Elevated intra-abdominal pressure in acute decompensated heart failure: a potential contributor to worsening renal function? 总被引:1,自引:0,他引:1
Wilfried Mullens Zuheir Abrahams Hadi N Skouri Gary S Francis David O Taylor Randall C Starling Emil Paganini W H Wilson Tang 《Journal of the American College of Cardiology》2008,51(3):300-306
OBJECTIVES: This study sought to determine whether changes in intra-abdominal pressure (IAP) with aggressive diuretic or vasodilator therapy are associated with improvement in renal function in acute decompensated heart failure (ADHF). BACKGROUND: Elevated IAP (>or=8 mm Hg) is associated with intra-abdominal organ dysfunction. There is potential for ascites and visceral edema causing elevated IAP in patients with ADHF. METHODS: Forty consecutive patients admitted to a specialized heart failure intensive care unit for management of ADHF with intensive medical therapy were studied. The IAP was measured using a simple transvesical technique at time of admission and before removal of the pulmonary artery catheter. RESULTS: In our study cohort (mean age 59 +/- 13 years, mean left ventricular ejection fraction 19 +/- 9%, baseline serum creatinine 2.0 +/- 0.9 mg/dl), the mean baseline IAP was 8 +/- 4 mm Hg, with 24 (60%) patients having elevated IAP. Elevated IAP was associated with worse renal function (p = 0.009). Intensive medical therapy resulted in improvement in both hemodynamic measurements and IAP. A strong correlation (r = 0.77, p < 0.001) was observed between reduction in IAP and improved renal function in patients with baseline elevated IAP. However, changes in IAP or renal function did not correlate with changes in any hemodynamic variable. CONCLUSIONS: Elevated IAP is prevalent in patients with ADHF and is associated with impaired renal function. In the setting of intensive medical therapy for ADHF, changes in IAP were better correlated with changes in renal function than any hemodynamic variable. 相似文献
36.
Eskandarifard Ebrahim Silva Rui Nobari Hadi Clemente Filipe Manuel Pérez-Gómez Jorge Figueiredo António José 《Sport Sciences for Health》2022,18(2):297-305
Sport Sciences for Health - The purposes of this study were to describe the fitness and hormonal levels according to playing time (PT) (i.e., PT during season less (PT1) or more (PT2) than 50% of... 相似文献
37.
NicholasA. Clanton Shayne D. Hastings Griffin B. Foultz Julie A. Contreras Samantha S. Yee Hadi D. Arman April L. Risinger Doug E. Frantz 《ACS medicinal chemistry letters》2020,11(12):2534
Natural products have served as inspirational scaffolds for the design and synthesis of novel antineoplastic agents. Here we present our preliminary efforts on the synthesis and biological evaluation of a new class of electrophilic steroids inspired by the naturally occurring taccalonolides. We demonstrate that these simplified analogs exhibit highly persistent antiproliferative properties similar to the taccalonolides and retain activity against resistant cancer cell lines that warrants further preclinical development. 相似文献
38.
Mohammad Afzalimoghaddam Maryam Feyiz Khademi Hadi Mirfazaelian Pooya Payandemehr Ehsan Karimialavijeh Alireza Jalali 《The Journal of emergency medicine》2021,60(1):1-7
BackgroundThe reduction of shoulder dislocation requires adequate procedural sedation and analgesia. The mixture of midazolam and fentanyl is reported in the literature, but long-acting benzodiazepines in conjunction with fentanyl are lacking.Study ObjectiveOur aim was to compar e IV diazepam with IV midazolam in moderate procedural sedation (based on the classification of the American Society of Anesthesiologists) for the reduction of shoulder dislocation.MethodsThis was a randomized controlled clinical trial conducted from April 2019 to December 2019 in the emergency department of a university-affiliated hospital in Tehran, Iran. Participants were adult patients (aged 18–65 years) with anterior shoulder dislocation. Group A (n = 42) received diazepam 0.1 mg/kg plus fentanyl 1 μg/kg IV and group B received midazolam 0.1 mg/kg plus fentanyl 1 μg g/kg IV. Main outcomes measured were onset of muscle relaxation, time taken to reduction, total procedure time, number of the reduction attempts, patient recovery time, the occurrence of the adverse effects, amount of the pain reported by the patients using visual analog scale, and patients and physicians overall satisfaction with the procedure using a Likert scale question.ResultsEighty-one patients were included. The mean ± standard deviation time of the onset of the muscle relaxation and time taken to reduction was shorter in the diazepam plus fentanyl group (p = 0.016 and p = 0.001, respectively). Adverse effects and pain relief were not statistically different between the two groups. Patient recovery time and total procedure time was shorter in the midazolam plus fentanyl group (p = 0.008 and p = 0.02, respectively). The overall satisfaction of patients and physicians was higher in the diazepam plus fentanyl group.ConclusionsAs compared with midazolam plus fentanyl, diazepam plus fentanyl was superior in terms of the onset of the muscle relaxation, patient and physician satisfaction, and time taken to reduction. 相似文献
39.
Mohammad Taherdangkoo Mohammad Hadi Bagheri Mehran Yazdi Katherine P. Andriole 《Journal of digital imaging》2013,26(6):1116-1123
Since segmentation of magnetic resonance images is one of the most important initial steps in brain magnetic resonance image processing, success in this part has a great influence on the quality of outcomes of subsequent steps. In the past few decades, numerous methods have been introduced for classification of such images, but typically they perform well only on a specific subset of images, do not generalize well to other image sets, and have poor computational performance. In this study, we provided a method for segmentation of magnetic resonance images of the brain that despite its simplicity has a high accuracy. We compare the performance of our proposed algorithm with similar evolutionary algorithms on a pixel-by-pixel basis. Our algorithm is tested across varying sets of magnetic resonance images and demonstrates high speed and accuracy. It should be noted that in initial steps, the algorithm is computationally intensive requiring a large number of calculations; however, in subsequent steps of the search process, the number is reduced with the segmentation focused only in the target area. 相似文献