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排序方式: 共有990条查询结果,搜索用时 203 毫秒
71.
Najmeh Jaberi Atena Soleimani Mehran Pashirzad Hosein Abdeahad Fariba Mohammadi Mahdieh Khoshakhlagh Majid Khazaei Gordon A Ferns Amir Avan Seyed Mahdi Hassanian 《Journal of cellular biochemistry》2019,120(4):4757-4765
Atherosclerosis is an arterial disease associated with inflammation. Thrombin is a procoagulant and proinflammatory serine protease that contributes to the pathology of atherosclerosis by enhancing the expression of cell adhesion molecules, inducing the secretion of proinflammatory cytokines, activating inflammatory responses in atherosclerotic plaques, stimulating proliferation of aortic smooth muscle cells, and exacerbating vascular lesions at sites of injury. Hence, thrombin appears to be an important target for treatment of atherosclerosis and thrombin pharmacological inhibitors have significant therapeutic potency for suppressing inflammatory responses in cardiovascular diseases. This review summarizes the proinflammatory signaling functions of thrombin as well as the therapeutic potency of thrombin inhibitors in the pathogenesis of atherosclerosis and hence their potential therapeutic value in this condition. 相似文献
72.
73.
Bacterial diversity and function of aerobic granules engineered in a sequencing batch reactor for phenol degradation 总被引:7,自引:0,他引:7
Aerobic granules are self-immobilized aggregates of microorganisms and represent a relatively new form of cell immobilization developed for biological wastewater treatment. In this study, both culture-based and culture-independent techniques were used to investigate the bacterial diversity and function in aerobic phenol- degrading granules cultivated in a sequencing batch reactor. Denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes demonstrated a major shift in the microbial community as the seed sludge developed into granules. Culture isolation and DGGE assays confirmed the dominance of beta-Proteobacteria and high-G+C gram-positive bacteria in the phenol-degrading aerobic granules. Of the 10 phenol-degrading bacterial strains isolated from the granules, strains PG-01, PG-02, and PG-08 possessed 16S rRNA gene sequences that matched the partial sequences of dominant bands in the DGGE fingerprint belonging to the aerobic granules. The numerical dominance of strain PG-01 was confirmed by isolation, DGGE, and in situ hybridization with a strain-specific probe, and key physiological traits possessed by PG-01 that allowed it to outcompete and dominate other microorganisms within the granules were then identified. This strain could be regarded as a functionally dominant strain and may have contributed significantly to phenol degradation in the granules. On the other hand, strain PG-08 had low specific growth rate and low phenol degradation ability but showed a high propensity to autoaggregate. By analyzing the roles played by these two isolates within the aerobic granules, a functional model of the microbial community within the aerobic granules was proposed. This model has important implications for rationalizing the engineering of ecological systems. 相似文献
74.
Arya A Haghjoo M Zahra E Heydari A Ali Sadr-Ameli M 《Indian pacing and electrophysiology journal》2004,4(4):217-220
Observation of Coincident arrhythmias is not uncommon but the co-existence of idiopathic verapamil sensitive left ventricular tachycardia (ILVT) with other arrhythmias is very rare. We hereby presented a 30 year old male patient with a history of frequent episodes of palpitations and sustained narrow complex tachycardia. During electrophysiologic study two arrhythmias, one with narrow complexes which was shown to be typical atrioventricular nodal re-entrant tachycardia and the other with wide QRS complexes and right bundle branch block and left axis morphology, compatible with ILVT, were inducible. Radiofrequency catheter ablation of both arrhythmias was done at two consecutive sessions. The patient has remained asymptomatic without antiarrhythmic therapy for the past six months. 相似文献
75.
Chakir H Campos-Neto A Mojibian M Webb JR 《Microbes and infection / Institut Pasteur》2003,5(4):241-249
The cytokine IL-12 plays a critical role in inducing the production of IFN-gamma from T and NK cells and in the polarization of T cells towards the Th1 phenotype. IL-12 is comprised of two subunits (IL-12p40 and IL-12p35) that together form the biologically active p70 molecule, and IL-12 functions via binding to a heterodimeric receptor (IL-12Rbeta1 and IL-12Rbeta2). Previous studies utilizing mice deficient for either the IL-12 cytokine or the IL-12-induced signaling molecule STAT4 have established a critical role for IL-12 during infection with Leishmania major. However, these studies warrant careful re-interpretation in light of the recent discovery of the IL-12-related cytokine, IL-23, which utilizes the IL-12p40 chain in combination with an IL-12p35-related molecule, called p19, and a receptor comprised of the IL-12Rbeta1 chain plus a unique chain referred to as IL-23R. We analyzed the course of L. major infection in mice deficient for the IL-12-specific IL-12Rbeta2 subunit in order to assess the role of IL-12 signaling without disruption of the IL-23 pathway. After infection with L. major, IL-12Rbeta2KO mice of a resistant background (C57Bl/6) developed large cutaneous lesions similar to those developed by susceptible BALB/c mice. Draining lymph node cells from L. major-infected IL-12Rbeta2KO mice released the Th2 cytokines IL-4 and IL-5 after in vitro stimulation with Leishmania lysate but were completely devoid of IFN-gamma, consistent with a default towards a strong parasite-specific Th2 response. L. major-infected IL-12Rbeta2KO mice were also devoid of parasite-specific IgG2a antibodies, and interestingly, their footpad lesions ulcerated earlier than those of susceptible BALB/c mice. 相似文献
76.
Lee SH Dimock K Gray DA Beauchemin N Holmes KV Belouchi M Realson J Vidal SM 《Trends in genetics : TIG》2003,19(8):447-457
Genetic studies of host susceptibility to infection contribute to our understanding of an organism's response to pathogens at the immunological, cellular, and molecular levels. In this review we describe how the study of host genetics in mouse models has helped our understanding of host defense mechanisms against viral infection, and how this knowledge can be extended to human infections. We focus especially on the innate mechanisms that function as the host's first line of defense against infection. We also discuss the main issues that confront this field, as well as its future. 相似文献
77.
We selected two geographically close serpentine and non-serpentine populations of a Ni-hyperaccumulating plant (Alyssum inflatum) to investigate the influence of two common factors of serpentine soils: high Ni concentrations and low Ca/Mg quotients. Soils and plants were sampled from serpentine and non-serpentine substrates, and concentrations of Ca, Mg and Ni were measured. A hydroponic culture was used to compare growth and elemental composition responses of serpentine and non-serpentine plants to different Ca/Mg quotients and Ni concentrations in the nutrient solution. The Ca/Mg quotient for non-serpentine soils was 15 times higher than for serpentine soils, but there was no difference in the Ca/Mg quotient of plants from the two populations. In hydroponic culture, plants from both populations were able to survive at high Ca/Mg quotients. This result suggests that serpentine plants of A. inflatum do not necessarily need a substrate with a low Ca/Mg quotient for survival. Decreases in the Ca/Mg quotient in hydroponics decreased growth. The magnitude of this decrease was significantly greater in non-serpentine plants, suggesting a greater resistance of serpentine plants to low Ca/Mg quotients. Total Ni concentration in serpentine soils was 13 times higher than in non-serpentine soils, but ammonium nitrate-extractable concentrations of Ni in both soil types were similar. Ni concentrations in non-serpentine plants from their natural habitat were significantly lower than in serpentine plants, but there was no significant difference in Ni accumulation by plants of the two populations in hydroponic culture. However, increased concentrations of Ni in the hydroponic medium caused similar decreases in growth of both populations, indicating that Ni tolerance of the two populations was similar. 相似文献
78.
Narges Zamani Amirhossein Khoshgoftarmanesh Majid Afyuni 《International journal of phytoremediation》2015,17(5):456-463
The effect of Neotyphodium endophytes on growth parameters and zinc (Zn) tolerance and uptake was studied in two grass species of Festuca arundinacea and Lolium perenne. Plants were grown under different Zn concentrations (control, 200, 400, 800, and 1800 mg kg?1) in potted soil for 5 months. The results showed that the number of plant tillers was 85 and 51% greater in endophyte infected Festuca (FaEI) and Lolium (LpEI), respectively, compared to their endophyte free (EF) plants. Roots and shoots dry weights in infected Festuca were 87 and 9% greater than non-infected counterparts but in opposite, EF Lolium had 47 and 8% greater root and shoot dry weights than LpEI. Endophyte infected Festuca and Lolium improved chlorophyll fluorescence as Fv/Fm at high concentrations of Zn, showing their better chlorophyll functions and significant reduction of Zn stress in endophyte infected plants. Shoots of endophyte infectedFestuca had 82% greater concentration of Zn than EF Festuca when grown in soil containing 1800 mg kg?1 Zn. Festuca and Lolium may tolerate high Zn concentration in soil without reduction in shoot and root growth. Endophyte infection in Festuca may help the grass accumulate and transport more Zn in aboveground parts under Zn-stress, thereby aiding phytoremediation of contaminated soils. 相似文献
79.
A novel approach CE-Ploc is proposed for predicting protein subcellular locations by exploiting diversity both in feature and decision spaces. The
diversity in a sequence of feature spaces is exploited using hydrophobicity and hydrophilicity of amphiphilic pseudo amino
acid composition and a specific learning mechanism. Diversity in learning mechanisms is exploited by fusion of classifiers
that are based on different learning mechanisms. Significant improvement in prediction performance is observed using jackknife
and independent dataset tests. 相似文献
80.