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51.
52.
Elnaz Javanshir Samad Ghaffari Reza Hajizadeh Hanieh Sakha Sahar Ghodratizadeh Hadiseh Kavandi 《Journal of electrocardiology》2018,51(5):870-873
Background
Electrocardiogram (ECG) is the first available modality used in patients with chest pain and dyspnea in emergency rooms.We aimed to study differences between acute coronary syndrome (ACS) and acute pulmonary embolism (APE) in patients presented primarily with abnormal negative T waves on their admission Electrocardiogram.Methods
This research was a retrospective study in which 297 patients (97 patients with APE and 200 with ACS) were included. The patients were admitted to the emergency ward of a tertiary heart center between 2015 and 2017. In addition to the evaluation of distribution of negative T waves, the depth of the inverted precordial T waves was measured.Results
The mean age of patients was 62.0?±?11.4 in ACS group and 60.7?±?17.6 in APE group (P value?=?0.563). Total negative T in V3 and V4 in ACS and APE groups was 9.1?mm and 4.2?mm respectively (P value <0.001).Total magnitude of negative T in anterior leads divided by total magnitude of negative T in inferior leads for ACS and APE groups were 15.1?±?12.0 and 5.4?±?3.6 respectively (P value?=?0.001).ROC curves showed that total magnitude of negative T in V4 divided by negative T in V1 can be valuable. A cutoff point of 1.75 with sensitivity of 73.5% and specificity of 84.9% (95% CI 0.79–0.91 P?<?0.001) could differentiate APE patients from ACS patients.Conclusion
This study suggests that total magnitude of negative T in left precordial leads divided by right precordial leads can be valuable in differentiating APE from ACS. 相似文献53.
54.
Seyedezahra Hosseini Ghasabmahaleh Zahra Rezasoltani Afsaneh Dadarkhah Sanaz Hamidipanah Reza Kazempour Mofrad Sharif Najafi 《The American journal of medicine》2021,134(1):135-141
ObjectiveWe evaluated the efficacy of spinal manipulation for the management of nonacute lumbar radiculopathy.MethodsIn a university hospital we performed a randomized controlled trial with 2 parallel arms. Patients (n = 44) with unilateral radicular low back pain lasting more than 4 weeks were randomly allocated to manipulation and control groups. The primary outcome was the intensity of the low back pain on a visual analog scale. The secondary outcome was the Oswestry Disability Questionnaire score. We also measured spinal ranges of motion. The assessments were carried out at the baseline, immediately after intervention, and at 3 months’ follow-up. All patients underwent physiotherapy. The manipulation group received three sessions of manipulation therapy 1 week apart. For manipulation, we used Robert Maigne's technique.ResultsBoth groups experienced a decrease in back and leg pain significantly (all P ≤ 0.003). However, only the manipulation group showed significantly favorable results in the Oswestry scores (P < 0.001), and the straight leg raise test (P = 0.001). All ranges of motion increased significantly with manipulation (all P < 0.001), but the control group showed favorable results only in right and left rotations and in extension (all P < 0.001). Between-group analyses showed significantly better outcomes for manipulation in all measurements (all P ≤ 0.009) with large effect sizes.ConclusionSpinal manipulation improves the results of physiotherapy over a period of 3 months for patients with subacute or chronic lumbar radiculopathy. 相似文献
55.
56.
Mehdi Esfandyari-Manesh Seyed Hossein Mostafavi Reza Faridi Majidi Mona Noori Koopaei Nazanin Shabani Ravari Mohsen Amini Behrad Darvishi Seyed Nasser Ostad Fatemeh Atyabi Rassoul Dinarvand 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
Nanoparticles (NPs) play an important role in anticancer delivery systems. Surface modified NPs with hydrophilic polymers such as human serum albumin (HSA) have long half-life in the blood circulation system.Methods
The method of modified nanoprecipitation was utilized for encapsulation of paclitaxel (PTX) in poly (lactic-co-glycolic acid) (PLGA). Para-maleimide benzoic hydrazide was conjugated to PLGA for the surface modifications of PLGA NPs, and then HSA was attached on the surface of prepared NPs by maleimide attachment to thiol groups (cysteines) of albumin. The application of HSA provides for the longer blood circulation of stealth NPs due to their escape from reticuloendothelial system (RES). Then the physicochemical properties of NPs like surface morphology, size, zeta potential, and in-vitro drug release were analyzed.Results
The particle size of NPs ranged from 170 to 190 nm and increased about 20–30 nm after HSA conjugation. The zeta potential was about -6 mV and it decreased further after HSA conjugation. The HSA conjugation in prepared NPs was proved by Fourier transform infrared (FT-IR) spectroscopy, faster degradation of HSA in Differential scanning calorimetry (DSC) characterization, and other evidences such as the increasing in size and the decreasing in zeta potential. The PTX released in a biphasic mode for all colloidal suspensions. A sustained release profile for approximately 33 days was detected after a burst effect of the loaded drug. The in vitro cytotoxicity evaluation also indicated that the HSA NPs are more cytotoxic than plain NPs.Conclusions
HSA decoration of PLGA NPs may be a suitable method for longer blood circulation of NPs. 相似文献57.
58.
59.
Zahra Alizadeh Sani Ahmad Shalbaf Hamid Behnam Reza Shalbaf 《Journal of digital imaging》2015,28(1):91-98
Curve of left ventricular (LV) volume changes throughout the cardiac cycle is a fundamental parameter for clinical evaluation of various cardiovascular diseases. Currently, this evaluation is often performed manually which is tedious and time consuming and suffers from significant interobserver and intraobserver variability. This paper introduces a new automatic method, based on nonlinear dimensionality reduction (NLDR) for extracting the curve of the LV volume changes over a cardiac cycle from two-dimensional (2-D) echocardiography images. Isometric feature mapping (Isomap) is one of the most popular NLDR algorithms. In this study, a modified version of Isomap algorithm, where image to image distance metric is computed using nonrigid registration, is applied on 2-D echocardiography images of one cycle of heart. Using this approach, the nonlinear information of these images is embedded in a 2-D manifold and each image is characterized by a symbol on the constructed manifold. This new representation visualizes the relationship between these images based on LV volume changes and allows extracting the curve of the LV volume changes automatically. Our method in comparison to the traditional segmentation algorithms does not need any LV myocardial segmentation and tracking, particularly difficult in the echocardiography images. Moreover, a large data set under various diseases for training is not required. The results obtained by our method are quantitatively evaluated to those obtained manually by the highly experienced echocardiographer on ten healthy volunteers and six patients which depict the usefulness of the presented method. 相似文献
60.
Nafise Tabasi Mahmoud Mahmoudi Maryam Rastin Hamid Reza Sadeghnia Mojtaba HosseinPour Mashhadi Shahrzad Zamani Taghizade Rabe 《Food and Agricultural Immunology》2015,26(1):138-156
Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers. 相似文献