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351.
Mona Abdolrazaghi Mahdi Navidbakhsh 《Computer methods in biomechanics and biomedical engineering》2013,16(5):567-576
Background: Ischemic heart diseases now afflict thousands of Iranians and are the major cause of death in many industrialised countries. Mathematical modelling of an intra-aortic balloon pump (IABP) could provide a better understanding of its performance and help to represent blood flow and pressure in systemic arteries before and after inserting the pump. Methods: A mathematical modelling of the whole cardiovascular system was formulated using MATLAB software. The block diagram of the model consists of 43 compartments. All the anatomical data was extracted from the physiological references. In the next stage, myocardial infarction (MI) was induced in the model by decreasing the contractility of the left ventricle. The IABP was mathematically modelled and inserted in the model in the thoracic aorta I artery just before the descending aorta. The effects of IABP on MI were studied using the mathematical model. Results: The normal operation of the cardiovascular system was studied firstly. The pressure–time graphs of the ventricles, atriums, aorta, pulmonary system, capillaries and arterioles were obtained. The volume–time curve of the left ventricle was also presented. The pressure–time curves of the left ventricle and thoracic aorta I were obtained for normal, MI, and inserted IABP conditions. Model verification was performed by comparing the simulation results with the clinical observations reported in the literature. Conclusions: IABP can be described by a theoretical model. Our model representing the cardiovascular system is capable of showing the effects of different pathologies such as MI and we have shown that MI effects can be reduced using IABP in accordance with the modelling results. The mathematical model should serve as a useful tool to simulate and better understand cardiovascular operation in normal and pathological conditions. 相似文献
352.
Torsten Goldmann Daniel Kähler Holger Schultz Mahdi Abdullah Dagmar S Lang Florian Stellmacher Ekkehard Vollmer 《Diagnostic pathology》2009,4(1):1-5
Background
As there is no optimal treatment of non small cell lung cancer due to its resistance to common chemotherapeutics, we investigated the effect of human placenta-conditioned medium on tumor tissue. The human placenta constitutes a mixture of maternal and fetal origin and displays a variety of immunomodulatory aspects.Methods
Freshly resected non small cell lung cancer tissues were incubated with placenta-conditioned medium in a short-term tissue culture model and A549 cells were challenged, respectively. Term placenta was used for producing conditioned medium and HOPE-fixed stimulated tumor tissue was analyzed for expression of caspase-3 and Ki67 via immunohistochemistry. The effects of conditioned medium on squamous cell carcinoma were further compared to physiological concentrations of Carboplat/Gemzar.Results
Conditioned medium caused in 2 of 3 cases elevated expression of caspase-3 and reduced expression of Ki67 in 3 out of 3 cases, while the chemotherapeutic agents caused no comparable expression of caspase-3 or reduction of Ki67. In cell culture up to 50% of karyopyknosis was investigated and even sterile-filtrated medium caused widespread reduction of Ki67 on protein level.Conclusion
Human placenta releases substances that mediate apoptosis and reduce proliferation in tumor tissue and cell culture. As even sterile-filtrated medium caused the mentioned effects we hypothesize one or more soluble mediators. The detailed way of promoting apoptosis and nature of these mediators need to be elucidated in further studies. 相似文献353.
El Mahdi Bendif Ian Probert Declan C. Schroeder Colomban de Vargas 《Journal of applied phycology》2014,26(3):1617-1617
354.
Yousof Gheisari Seyed Mahdi Nassiri Ehsan Arefian Naser Ahmadbeigi Kayhan Azadmanesh Mansour Jamali Issa Jahanzad Sirous Zeinali Mohammad Vasei Masoud Soleimani 《Cytotherapy》2010,12(3):303-312
Background aimsTissue-specific stem cells are a promising target for kidney regeneration, because it has been shown that they play a primary role in kidney repair. Several methods have been developed for the isolation of stem/progenitor cells from healthy kidneys but the existence of these cells in chronically damaged kidneys has not been noticed so far.MethodsA mouse model of chronic kidney failure was developed by ligation of the left ureter for 5 months, and then isolation of stem cells from this tissue as well as normal kidneys was attempted.ResultsWe found that multipotent stem cells could be isolated from both types of tissue. In addition, the cells isolated from damaged kidneys showed potential for homing to the site of injury and a renoprotective effect in an animal model of cisplatin-induced nephropathy.ConclusionsThese results show that multipotent renoprotective stem cells exist in severely damaged kidneys, which could be a target for designing new therapies. 相似文献
355.
Faraji Fatemeh Habibi-Anbouhi Mahdi Behdani Mahdi Kazemi-Lomedasht Fatemeh Shokrgozar Mohammad Ali Zarnani Amir-Hassan Tajik Nader 《International journal of peptide research and therapeutics》2020,26(2):633-639
International Journal of Peptide Research and Therapeutics - Variable antigen-binding domain of camelid single chain antibodies (VHH, Nanobody) and its conjugates are considered among very... 相似文献
356.
Spykman Raphaela Hossaini Sayed Mahdi Peguero Daniela A. Green Ashley Heinz Volker Smetana Sergiy 《The International Journal of Life Cycle Assessment》2021,26(10):1959-1976
The International Journal of Life Cycle Assessment - The inclusion of insect protein into the food system has been proposed as a promising solution to ensure future food security and mitigate... 相似文献
357.
Mojtaba Shamsipur Seied Mahdi Pourmortazavi Ali Akbar Miran Beigi Rouhollah Heydari Mina Khatibi 《AAPS PharmSciTech》2013,14(1):287-293
Investigations on thermal behavior of drug samples such as acyclovir and zidovudine are interesting not only for obtaining stability information for their processing in pharmaceutical industry but also for predicting their shelf lives and suitable storage conditions. The present work describes thermal behaviors and decomposition kinetics of acyclovir and zidovudine in solid state, studied by some thermal analysis techniques including differential scanning calorimetry (DSC) and simultaneous thermogravimetry–differential thermal analysis (TG/DTA). TG analysis revealed that thermal degradation of the acyclovir and zidovudine is started at the temperatures of 400°C and 190°C, respectively. Meanwhile, TG–DTA analysis of acyclovir indicated that this drug melts at about 256°C. However, melting of zidovudine occurred at 142°C, which is 100°C before starting its decomposition (242°C). Different heating rates were applied to study the DSC behavior of drug samples in order to compute their thermokinetic and thermodynamic parameters by non-isothermal kinetic methods. Thermokinetic data showed that both drugs at the room temperature have slow degradation reaction rates and long shelf lives. However, acyclovir is considerably more thermally stable than zidovudine. 相似文献
358.
Peter Gyulai Mohammad Mahdi Rabieh Ali Asghar Seraj Laslo Ronkay Mehdi Esfandiari 《ZooKeys》2013,(317):17-25
A new Anagnorisma species, Anagnorisma chamrani
sp. n., is described from Binaloud Mountains of Khorasan-e-Razavi province in north-eastern Iran, and compared with its sister species, Anagnorisma eucratides (Boursin, 1960). The adults, and male and female genitalia of both species are illustrated in 11 figures. The genus Anagnorisma is recorded for the first time for the fauna of Iran. 相似文献
359.
Syed Rizwan Hussain Hena Naqvi Farzana Mahdi Cherry Bansal Sunil G. Babu 《Molecular biotechnology》2013,54(2):461-468
The KIT gene is a receptor tyrosine kinase class III expressed by early hematopoietic progenitor cells and plays a significant role in hematopoietic stem cell proliferation, differentiation and survival which is considered to be a remarkable feature in the course of growth of acute myeloid leukaemia (AML). Owing to insufficient study of mutations in the KIT gene, the diagnosis and rate of recurrence of these mutations with divergent subtypes in AML cases in India is of concern. In order to find out the frequency of mutations of KIT gene exon 8 in 109 AML cases, we have performed polymerase chain reaction–single-strand conformation polymorphism (PCR–SSCP) followed by DNA sequencing and have identified 24 mutations in exon 8 in 13 cases, including deletions at codon 418 (n = 3), 419 (n = 11) and 420 (n = 5) as well as point mutations at codon 417 (n = 1) and 421 (n = 4). In eleven AML cases, exon 8 deletion and point mutations involved the loss at codon Asp419 immoderately conserved cross species placed in the receptor extracellular domain. Frequency elevation of the KIT proto-oncogene exon 8 deletion and point mutations in AML cases allude a crucial function for this region of the receptor extracellular domain. Thus, we report the incidence of acquired mutations in exon 8, with consistent loss at codon Asp419, in 10.09 % of AML cases in a selected Indian population. 相似文献
360.
El Mahdi Bendif Kazuhiro Kogame Ian Probert Yoshihito Takano Takeo Horiguchi Colomban de Vargas Hisatake Okada 《Journal of phycology》2011,47(5):1164-1176
Emiliania huxleyi (Lohmann) W. W. Hay et H. Mohler is a cosmopolitan coccolithophore occurring from tropical to subpolar waters and exhibiting variations in morphology of coccoliths possibly related to environmental conditions. We examined morphological characters of coccoliths and partial mitochondrial sequences of the cytochrome oxidase 1b (cox1b) through adenosine triphosphate synthase 4 (atp4) genes of 39 clonal E. huxleyi strains from the Atlantic and Pacific Oceans, Mediterranean Sea, and their adjacent seas. Based on the morphological study of culture strains by SEM, Type O, a new morphotype characterized by coccoliths with an open central area, was separated from existing morphotypes A, B, B/C, C, R, and var. corona, characterized by coccoliths with central area elements. Molecular phylogenetic studies revealed that E. huxleyi consists of at least two mitochondrial sequence groups with different temperature preferences/tolerances: a cool‐water group occurring in subarctic North Atlantic and Pacific and a warm‐water group occurring in the subtropical Atlantic and Pacific and in the Mediterranean Sea. 相似文献