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排序方式: 共有1681条查询结果,搜索用时 31 毫秒
71.
Naghavi M Libby P Falk E Casscells SW Litovsky S Rumberger J Badimon JJ Stefanadis C Moreno P Pasterkamp G Fayad Z Stone PH Waxman S Raggi P Madjid M Zarrabi A Burke A Yuan C Fitzgerald PJ Siscovick DS de Korte CL Aikawa M Airaksinen KE Assmann G Becker CR Chesebro JH Farb A Galis ZS Jackson C Jang IK Koenig W Lodder RA March K Demirovic J Navab M Priori SG Rekhter MD Bahr R Grundy SM Mehran R Colombo A Boerwinkle E Ballantyne C Insull W Schwartz RS Vogel R Serruys PW Hansson GK Faxon DP Kaul S 《Circulation》2003,108(15):1772-1778
Atherosclerotic cardiovascular disease results in >19 million deaths annually, and coronary heart disease accounts for the majority of this toll. Despite major advances in treatment of coronary heart disease patients, a large number of victims of the disease who are apparently healthy die suddenly without prior symptoms. Available screening and diagnostic methods are insufficient to identify the victims before the event occurs. The recognition of the role of the vulnerable plaque has opened new avenues of opportunity in the field of cardiovascular medicine. This consensus document concludes the following. (1) Rupture-prone plaques are not the only vulnerable plaques. All types of atherosclerotic plaques with high likelihood of thrombotic complications and rapid progression should be considered as vulnerable plaques. We propose a classification for clinical as well as pathological evaluation of vulnerable plaques. (2) Vulnerable plaques are not the only culprit factors for the development of acute coronary syndromes, myocardial infarction, and sudden cardiac death. Vulnerable blood (prone to thrombosis) and vulnerable myocardium (prone to fatal arrhythmia) play an important role in the outcome. Therefore, the term "vulnerable patient" may be more appropriate and is proposed now for the identification of subjects with high likelihood of developing cardiac events in the near future. (3) A quantitative method for cumulative risk assessment of vulnerable patients needs to be developed that may include variables based on plaque, blood, and myocardial vulnerability. In Part I of this consensus document, we cover the new definition of vulnerable plaque and its relationship with vulnerable patients. Part II of this consensus document will focus on vulnerable blood and vulnerable myocardium and provide an outline of overall risk assessment of vulnerable patients. Parts I and II are meant to provide a general consensus and overviews the new field of vulnerable patient. Recently developed assays (eg, C-reactive protein), imaging techniques (eg, CT and MRI), noninvasive electrophysiological tests (for vulnerable myocardium), and emerging catheters (to localize and characterize vulnerable plaque) in combination with future genomic and proteomic techniques will guide us in the search for vulnerable patients. It will also lead to the development and deployment of new therapies and ultimately to reduce the incidence of acute coronary syndromes and sudden cardiac death. We encourage healthcare policy makers to promote translational research for screening and treatment of vulnerable patients. 相似文献
72.
73.
Taheri Mohammad Noroozi Rezvan Aghaei Kamyar Omrani Mir Davood Ghafouri-Fard Soudeh 《Metabolic brain disease》2020,35(3):497-501
Metabolic Brain Disease - Molybdenum cofactor sulfurase (MOCOS) gene encodes an enzyme which is involved in purine metabolism. Recent experiments have shown down-regulation of MOCOS in adult nasal... 相似文献
74.
Mahmood Saghali Seyyed Morteza Hoseini Seyed Abbas Hosseini Rauf Baqraf 《Bulletin of environmental contamination and toxicology》2014,92(1):57-60
The aim of the present study was to determine zinc (Zn), chromium (Cr), cadmium (Cd) and lead (Pb) content of benthic fauna in the southeast coast of the Caspian Sea, where the major fish restocking programs are conducted. Seasonal sampling was performed in three sampling sites: north Miankaleh (NM), south Miankaleh (SM) and Gharesoo coast (GC). Results showed that sampling sites, sampling seasons and sampling sites × sampling seasons interaction had a significant effect on the heavy metal levels (p < 0.05). The yearly heavy metal concentration order was as follows: Zn > Pb > Cd > Cr. Yearly Pb levels of the NM site were significantly higher than the other sites. Also, yearly Cr levels of the SM site were significantly higher than site GC. Comparison of the benthos heavy metal levels with the available reference values suggests that the benthos tissues might be highly polluted which can intoxicate the fish feeding on them. 相似文献
75.
Marina V. Pryzhkova Indrat Aria Qingsu Cheng Greg M. Harris Xingjie Zan Morteza Gharib Ehsan Jabbarzadeh 《Biomaterials》2014
We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment. 相似文献
76.
Shima Taheri Alex Cavallaro Susan N. Christo Louise E. Smith Peter Majewski Mary Barton John D. Hayball Krasimir Vasilev 《Biomaterials》2014
Infections arising from bacterial adhesion and colonization on medical device surfaces are a significant healthcare problem. Silver based antibacterial coatings have attracted a great deal of attention as a potential solution. This paper reports on the development of a silver nanoparticles based antibacterial surface that can be applied to any type of material surface. The silver nanoparticles were surface engineered with a monolayer of 2-mercaptosuccinic acid, which facilitates the immobilization of the nanoparticles to the solid surface, and also reduces the rate of oxidation of the nanoparticles, extending the lifetime of the coatings. The coatings had excellent antibacterial efficacy against three clinically significant pathogenic bacteria i.e. Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa. Studies with primary human fibroblast cells showed that the coatings had no cytotoxicity in vitro. Innate immune studies in cultures of primary macrophages demonstrated that the coatings do not significantly alter the level of expression of pro-inflammatory cytokines or the adhesion and viability of these cells. Collectively, these coatings have an optimal combination of properties that make them attractive for deposition on medical device surfaces such as wound dressings, catheters and implants. 相似文献
77.
Belal Hassanzadeh Abolghasem Nabipour Morteza Behnam Rassouli Hesam Dehghani 《Anatomical science international / Japanese Association of Anatomists》2014,89(3):129-139
Although the histological structure of ostrich testis has been studied, very little information is currently available on the embryonic development of this organ. The aim of this study was to determine the sequence of the histological changes in diverse components of the testis in ostrich embryo from embryonic day (E) 20 to E42. The main findings were categorized into four histological features, i.e., development of sex cords, interstitial tissue and rete ducts, and the appearance of defective septa. While the lumen of sex cords, tunica albuginea, capsular rete ducts and Leydig cell precursors appeared at E26, the filum-shaped defective septa were visible at E36. The emersion of the lumen in the primary sex cords and formation of capsular rete ducts in the ostrich embryo is considerably different from that in other birds. However, tunica albuginea and Leydig cell precursors appeared in a similar pattern to those of other birds. An interesting observation was that the primordial germ cell (PGC)-like cells were completely distinct, while the capsular rete ducts were formed by trapping of some Sertoli cell aggregations in the tunica albuginea. This suggests that similar to the primary sex cords, the capsular rete ducts may originate from the Sertoli cell aggregations which had corralled some PGCs. Stereological estimations in the ostrich embryo testis showed the major proportion of testis is occupied by the seminiferous tubules, which is unlike the fowl embryo testis. 相似文献
78.
Ahmad Reza Hosseini Ruholla Rahimi Ali Taheri Mirghaed 《Comparative clinical pathology》2014,23(3):775-778
In this study, the histamine concentration in the muscle tissue of whole rainbow trout (Oncorhynchus mykiss) was monitored during ice storage for a period of 18 days (0, 3, 6, 9, 12, 15 and 18th day). Results showed that the concentration of histamine increased linearly (P?<?0.05) during ice storage (except the 18th day). Histamine was not detected at the first and third day of storage. The first detection of histamine was in the sixth storage day. Initial concentration of histamine was 1.09 μg/g and finally reached to 4.30 μg/g. The maximum histamine levels was reported to be below the Australian Food Standards Code (2001) safe level (200 mg/kg), and histamine levels were low even after 18 days of storage and remained below the Food and Drug Administration (2001) tolerance level during ice storage. It seems that the levels of histamine could be a suitable freshness indicator of rainbow trout during ice storage. 相似文献
79.
Shamsa Ahmadian Morteza Khaghanizadeh Ebrahim Khaleghi Mohammad Hossein Zarghami 《Death Studies》2020,44(12):759-770
AbstractMore is known about organ donor recipients than donor families. We explored the stressors experienced by family members of brain-dead people during the process of organ donation. Seventeen family members and five organ procurers were interviewed and the data analyzed through conventional qualitative content analysis. Stressors experienced by family members fell into six themes—perceived threat of loss, decision making under conflict, painful corrosive farewell, feeling of insecurity, complexity of grief, and seeking relief. Findings highlight the necessity of developing and using standard protocols for supporting brain-dead people’s family members throughout the process of organ donation and following bereavement. 相似文献
80.
Khadijeh Hooshyari Samira Heydari Mehran Javanbakht Hossein Beydaghi Morteza Enhessari 《RSC advances》2020,10(5):2709
The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO3 perovskite nanoparticles. Nanocomposite membranes based on SPPEK and SrTiO3 perovskite nanoparticles were prepared via a casting method. The highest proton conductivity of nanocomposite membranes obtained was 120 mS cm−1 at 90 °C and 95% RH. These enhancements could be related to the hygroscopic structure of SrTiO3 perovskite nanoparticles and the formation of hydrogen bonds between nanoparticles and water molecules. The satisfactory power density, 0.41 W cm−2 at 0.5 V and 85 °C, of the nanocomposite membrane (5 wt% content of nanoparticles) confirms their potential for application in the PEM fuel cells.The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO3 perovskite nanoparticles. 相似文献