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81.
Herein, we developed a novel homogeneous liquid–liquid microextraction based on liquid nitrogen-induced phase separation (HLLME-LNPS) for the extraction and determination of lead (Pb) in Pb-adulterated opium and refined opium by GFAAS analysis. In this procedure, first, 400 μl of acetonitrile (extractant) containing 7.0 μl of diethyl dithiophosphoric acid (DDTP) is injected into a sample solution and a homogeneous solution is formed. Subsequently, the homogeneous mixture is cooled using liquid nitrogen for 16 seconds. By this process, due to the difference in the freezing points of the organic and aqueous phases, the homogeneous state is broken and the Pb-DDTP species are extracted into the liquid organic phase collected on top of the frozen aqueous phase. The introduced method exhibited a good linearity with a coefficient of determination (r2) of 0.9988 and an acceptable linear range of 0.6–100 μg l−1. Accordingly, the detection limit was 0.2 μg l−1 (S/N = 3) for Pb ions, and a high enrichment factor was obtained. The proposed method was successfully utilized to determine trace levels of Pb in opium samples. The results of the sample analysis showed that 65% of the opium samples and 85% of the refined opium samples had much higher than expected levels of contaminating Pb, and this contamination poses a serious threat to drug users.Herein, we developed a novel homogeneous liquid–liquid microextraction based on liquid nitrogen-induced phase separation (HLLME-LNPS) for the extraction and determination of lead (Pb) in Pb-adulterated opium and refined opium by GFAAS analysis. 相似文献
82.
Reza Barati rashvanlou Abbas Rezaee Mahdi Farzadkia Mitra Gholami Majid Kermani 《RSC advances》2020,10(59):35718
Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. 相似文献
83.
Arwa Ibrahim Al-Mogherah Mohamed Abbas Ibrahim Maha Abdelazeem Hassan 《Saudi Pharmaceutical Journal》2020,28(11):1374-1382
Three factors, three levels (33) full factorial design was used to develop venlafaxine HCl fast dissolving oral films (FDOFs) to optimize the concentrations of the film forming polymer; hydroxypropyl methylcellulose HPMC (X1), superdisintegrant; sodium starch glycolate SSG, (X2) and glycerol as the film plasticizer (X3). Effects of the three factors on the disintegration time (Y1), swelling index (Y2), and dissolution efficiency at 15 min; DE%15 (Y3) of the prepared FDOFs were evaluated by using statistical models. The optimized film formula was characterized in term of x-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and morphological characteristics.Disintegration time was found to increase with the increase in HPMC (X1) concentration, and the shortest disintegration time (21.67 ± 2.08 s) was observed in case of F2 formula (lowest HPMC level and highest glycerol level in absence of SSG). The highest swelling index (3.64 ± 0.59) was observed in case of film formula F1 (medium concentrations of both HPMC and glycerol and highest SSG concentration. The results also indicated that as the concentration of HPMC increased the DE%15 decreased. SSG (X2), with highest value (72.33 ± 1.71%) was recorded for in case of F12 (using 2% HPMC, 5%SSG and 1.5% glycerol). The optimized FDOF formula derived by the statistical models suggested 2% HPMC, 5% SSG, and 1% glycerol.The data obtained from DSC and XRPD revealed no interaction between drug and FDOT excipients. In addition, XRPD studies proved that the venlafaxine HCl was homogeneously dispersed in the film matrix. 相似文献
84.
A Abbas K A G Garfath-Cox I W Brown J S Shambrook C R Peebles S P Harden 《The British journal of radiology》2015,88(1045)
Cardiac myxomas are the most common benign primary cardiac tumour to present in adulthood. While most patients present with symptoms of cardiac obstruction, embolic phenomena or constitutional impairment, up to a fifth of patients remain asymptomatic and are incidentally diagnosed on imaging. Although echocardiography is usually the initial imaging modality used to evaluate these patients, cardiac MRI (CMR) has emerged over the past decade as the primary imaging modality in the assessment of patients with cardiac tumours. The superior tissue characterization capability of CMR means that it is able to determine the nature of some tumours pre-operatively and performs well in differentiating myxomas from thrombus. We present a pictorial review highlighting the key CMR features of myxomas and show how these lesions can be differentiated from thrombus and other cardiac masses.Primary cardiac tumours are uncommon with a reported prevalence at autopsy of 0.002%.1 The majority are benign, with myxomas accounting for almost 50% of all primary cardiac tumours.2 Myxomas are more common in female patients, and while they can occur at any age, they usually present in adults between the fourth and seventh decades of life.3,4 Most patients typically present with at least one manifestation of the classic triad of cardiac obstructive symptoms, embolic phenomena and constitutional symptoms, but 20% are identified in asymptomatic patients as an incidental imaging finding.3Echocardiography is usually the initial imaging modality used in the assessment of a suspected cardiac mass but remains rather operator dependent with a restricted field of view and can be particularly challenging in patients with large body habitus.2,4,5 Cardiac MRI (CMR) enables accurate assessment of the location and functional impact of cardiac masses in any imaging plane without exposing patients to ionizing radiation.2,5 In particular, CMR performs better than echocardiography at determining the nature of cardiac lesions and can differentiate myxomas from thrombus.2,5 Given that most cardiac lesions are not easily amenable to catheter-directed biopsy, accurate imaging differentiation of cardiac myxomas from other types of cardiac masses is of vital importance in guiding further management. 相似文献
85.
Shirazi Mohsen Ahmad Akhoundi Mohammad Sadegh Javadi Ehsan Kamali Abbas Motahhari Pouria Rashidpour Mahsa Chiniforush Nasim 《Lasers in medical science》2015,30(2):713-718
Lasers in Medical Science - Low-level laser has been indicated to have the capability to facilitate the differentiation of the osteoclastic and osteoblastic cells which are responsible for the bone... 相似文献
86.
87.
Shimpei Yamada Ken Tomida Genichi Tanino Akira Suzuki Kenji Kawakami Shinji Kubota Ryuzo Yanohara Youhei Katoh Yosuke Wada Toshio Teranishi Abbas Orand Yutaka Tomita Shigeru Sonoda 《Journal of Physical Therapy Science》2015,27(4):1247-1250
[Purpose] The purpose of this study was to find whether a fast treadmill gait training
speed is effective for the gait training of stroke patients in the early rehabilitation
stage. [Subjects and Methods] Thirty-nine stroke patients were the subjects of our
investigation. They walked on a treadmill with handrail supports at a fast speed (130% of
their comfortable gait speed in the 2nd week). The treadmill gaits of the patients were
recorded using a 3-dimensional analysis system at two and six weeks after their
admissions. Intraclass Correlation Coefficients (ICC) of the temporal and spatial
parameters of the two periods were statistically analyzed. [Results] For all of the
patients, the ICCs of the measured parameters were greater than 0.58. In the case of
patients whose gait speeds of the two periods were close, the ICC units were greater than
0.7. [Conclusion] The fast gait speed training allowed us to expose the patients to a gait
speed that they were expected to acquire at a later stage of their rehabilitation. This
training method was found to be beneficial for the mildly paralyzed patients.Key words: Stroke, Treadmill, Fast speed 相似文献
88.
89.
Mohd Faizan Latif Zafar Jilani Mazhar Abbas Yasir Salam Siddiqui Aamir Bin Sabir M.K.A. Sherwani Saifullah Khalid 《中华创伤杂志(英文版)》2015,18(3):181-183
Inferior glenohumeral dislocation is the least common type of glenohumeral dislocations. It may be
associated with fractures of the adjacent bones and neurovascular compromise. It should be treated
immediately by close reduction. The associated neuropraxia usually recovers with time. Traction-counter traction method is commonly used for reduction followed by immobilization of the shoulder for three weeks. Here, we report a case of inferior glenohumeral joint dislocation with greater tuberosity fracture with transient neurovascular compromise and present a brief review of the literature. 相似文献
90.