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101.
Effect of disturbance on root colonization and vertical distribution of arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) was investigated at two adjacent sites of Lal Suhanra Biosphere Reserve, Pakistan. Disturbance clearly affected AMF and DSE colonization, vertical distribution of AMF and plant community structure. Mean colonization of AMF and DSE was slightly less at the disturbed site. Average spore densities, diversity and richness of AMF and DSE were higher at the undisturbed site. A study of the vertical distribution of AMF associated with the five plant species most common to each study site indicated that beside AMF and DSE colonization disturbance may affect AMF species composition. Correlation of AMF with DSE is also discussed.  相似文献   
102.
Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+ (n = 300) and CAD (n = 100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD and control groups. Anti-Hsp27 titers were also higher in the CAD group compared with the control group. With regard to the number of affected vessels in the CAD+ group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease.  相似文献   
103.
Predicting gene expression from sequence   总被引:36,自引:0,他引:36  
Beer MA  Tavazoie S 《Cell》2004,117(2):185-198
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104.
The frequency of in vitro callus induction and plant regeneration is influenced by several factors, including composition of culture medium, explant source, and the genotype. Crosses between regenerable and non-regenerable upland cotton cultivars were evaluated for hybrid vigour towards regeneration responses, which is consequential in recalcitrant crop species like cotton where regeneration is limited only to a few cultivars. The results indicated that regenerable and non-regenerable parental cultivars had similar potential of producing callus, but differed in producing callus weight and embryogenic calli. Mean performance of crosses, regarding callus induction, callus weight, callus growth rate, percent embryo induction, and percentage of germinating embryos, deviated considerably from the performance of their parents, signifying the presence of hybrid vigour for the expression of these traits. Magnitude of hybrid vigour varied across hormonal levels. Genetic component was evident for all the traits although of lower magnitude. The results indicated that genetic component in the phenotypic expression of callus growth, percentages of embryo induction and germinating embryos was higher than that of callus induction, callus weight and percentage of embryogenic calli. Hormonal concentration in the media had affect on the degree of gene expression responsible for regeneration in upland cotton. Over, partial- and additive-dominance types of gene effects were apparent in the expression of these traits. Genotype × growth regulator level interaction caused considerable variation in the expression of regeneration responses, suggesting that determination of specific level of growth regulator concentration in the medium was necessary for a particular genotype to obtain optimum response. Genotype × explant source interaction was, however, relatively less important. Differences among genotypes for percent embryo induction were clearly evident.  相似文献   
105.
106.
International Journal of Peptide Research and Therapeutics - Chemotherapy using drug delivery systems can target tumor cells selectively and do not affect normal cells. In this paper, a specific...  相似文献   
107.
108.
Purinergic Signalling - Recent studies have shown that mesenchymal stem cells (MSCs) and their conditioned medium (CM) have potential therapeutic effects in animal models of neuropathic pain (NP)....  相似文献   
109.
International Journal of Peptide Research and Therapeutics - Ovarian cancer is one of the most lethal gynecologic cancers. The high mortality rate is due to lack of early symptoms and developing...  相似文献   
110.
Nowadays, increased use of nanomaterials in industry and biomedicine poses potential risks to human health and the environment. Studying their possible toxicological effects is therefore of great significance. The present investigation was designed to examine the status of oxidative stress induced by nanoparticles (NPs) of ferric oxide (Fe2O 3) and titanium oxide (TiO 2) with their micro-sized counterpart on mouse lung and bone marrow–derived normal tissue cells. We assessed the induction of oxidative stress by measuring its indicators such as antioxidant scavenging activity of superoxide dismutase and catalase as well as malondialdehyde concentration. Moreover, colony formation of bone marrow cells was assayed following induction with colony stimulating factor (CSF) from lung cells. NPs had a more potent stimulatory effect on the oxidative stress status than their micron-sized counterparts. In addition, the highest level of oxidative stress derived from TiO 2 NPs was observed in both tissue types. Cotreatment with NPs and the antioxidant α-tocopherol reduced antioxidant activities and membrane lipid peroxidation (LPO) in the lung cells, but increased CSF-induced colony formation activity of bone marrow cells, suggesting that oxidative stress may be the cause of the cytotoxic effects of NPs. It is concluded that free radicals generated following exposure to NPs resulted in significant oxidative stress in mouse cells, indicated by increased LPO and antioxidant enzyme activity and decreased colony formation.  相似文献   
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