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排序方式: 共有195条查询结果,搜索用时 54 毫秒
101.
Effect of NaCl and Proline on Bean Seedlings Cultured in vitro 总被引:3,自引:0,他引:3
Effects of NaCl (150 mM), proline (10 mM) and their combination on growth and contents of chlorophyll, proline and protein of bean (Phaseolus vulgaris cv. Kizilhaç) seedlings in vitro were investigated. NaCl decreased seedling growth. Proline added to control seedlings did not change seedling growth but decreased chlorophyll and increased protein contents. When proline added to NaCl-treated seedlings growth was increased in comparison with NaCl-treated only. Thus, proline alleviated salinity stress in bean seedlings. 相似文献
102.
Atilla Cayir Hakan Doneray Nezahat Kurt Zerrin Orbak Avni Kaya Mehmet Ibrahim Turan Abdulkadir Yildirim 《Biological trace element research》2014,157(2):95-100
Obesity is a multifactorial disease developing following impairment of the energy balance. The endocrine system is known to be affected by the condition. Serum thyroid hormones and trace element levels have been shown to be affected in obese children. Changes in serum thyroid hormones may result from alterations occurring in serum trace element levels. The aim of this study was to evaluate whether or not changes in serum thyroid hormone levels in children with exogenous obesity are associated with changes in trace element levels. Eighty-five children diagnosed with exogenous obesity constituted the study group, and 24 age- and sex-matched healthy children made up the control group. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (TG), selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn) levels in the study group were measured before and at the third and sixth months of treatment, and once only in the control group. Pretreatment fT4 levels in the study group rose significantly by the sixth month (p?=?0.006). Zn levels in the patient group were significantly low compared to the control group (p?=?0.009). Mn and Se levels in the obese children before and at the third and sixth months of treatment were significantly higher than those of the control group (p?=?0.001, p?=?0.001). In conclusion, fT4, Zn, Cu, Mn, and Se levels are significantly affected in children diagnosed with exogenous obesity. The change in serum fT4 levels is not associated with changes in trace element concentrations. 相似文献
103.
Edink E Akdemir A Jansen C van Elk R Zuiderveld O de Kanter FJ van Muijlwijk-Koezen JE Smit AB Leurs R de Esch IJ 《Bioorganic & medicinal chemistry letters》2012,22(3):1448-1454
Using structure-based optimization procedures on in silico hits, dibenzosuberyl- and benzoate substituted tropines were designed as ligands for acetylcholine-binding protein (AChBP). This protein is a homolog to the ligand binding domain of the nicotinic acetylcholine receptor (nAChR). Distinct SAR is observed between two AChBP species variants and between the α7 and α4β2 nAChR subtype. The AChBP species differences are indicative of a difference in accessibility of a ligand-inducible subpocket. Hereby, we have identified a region that can be scrutinized to achieve selectivity for nicotinic receptor subtypes. 相似文献
104.
Naiki Y Sorrentino R Wong MH Michelsen KS Shimada K Chen S Yilmaz A Slepenkin A Schröder NW Crother TR Bulut Y Doherty TM Bradley M Shaposhnik Z Peterson EM Tontonoz P Shah PK Arditi M 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(10):7176-7185
Experimental and clinical studies link Chlamydia pneumoniae infection to atherogenesis and atherothrombotic events, but the underlying mechanisms are unclear. We tested the hypothesis that C. pneumoniae-induced acceleration of atherosclerosis in apolipoprotein E (ApoE)(-/-) mice is reciprocally modulated by activation of TLR-mediated innate immune and liver X receptor alpha (LXRalpha) signaling pathways. We infected ApoE(-/-) mice and ApoE(-/-) mice that also lacked TLR2, TLR4, MyD88, or LXRalpha intranasally with C. pneumoniae followed by feeding of a high fat diet for 4 mo. Mock-infected littermates served as controls. Atherosclerosis was assessed in aortic sinuses and in en face preparation of whole aorta. The numbers of activated dendritic cells (DCs) within plaques and the serum levels of cholesterol and proinflammatory cytokines were also measured. C. pneumoniae infection markedly accelerated atherosclerosis in ApoE-deficient mice that was associated with increased numbers of activated DCs in aortic sinus plaques and higher circulating levels of MCP-1, IL-12p40, IL-6, and TNF-alpha. In contrast, C. pneumoniae infection had only a minimal effect on atherosclerosis, accumulation of activated DCs in the sinus plaques, or circulating cytokine increases in ApoE(-/-) mice that were also deficient in TLR2, TLR4, or MyD88. However, C. pneumoniae-induced acceleration of atherosclerosis in ApoE(-/-) mice was further enhanced in ApoE(-/-)LXRalpha(-/-) double knockout mice and was accompanied by higher serum levels of IL-6 and TNF-alpha. We conclude that C. pneumoniae infection accelerates atherosclerosis in hypercholesterolemic mice predominantly through a TLR/MyD88-dependent mechanism and that LXRalpha appears to reciprocally modulate and reduce the proatherogenic effects of C. pneumoniae infection. 相似文献
105.
Svoboda J Kozubíková E Kozák P Kouba A Bahadir Koca S Diler O Diler I Policar T Petrusek A 《Diseases of aquatic organisms》2012,98(3):255-259
Many populations of the narrow-clawed crayfish Astacus leptodactylus in Turkey, including those inhabiting Lake E?irdir, declined drastically in the mid-1980s due to introduction of crayfish plague Aphanomyces astaci. However, unlike many other localities, there has been some recovery in the A. leptodactylus population inhabiting this lake even though crayfish plague has been suspected to have persisted since then. In support of this, DNA from 5 of 34 healthy-looking crayfish sampled recently from the lake tested positive by both conventional and real-time PCR using species-specific primers targeting the rDNA internal transcribed spacer region, and product sequence analysis confirmed the identification of A. astaci. This complies with other recent reports of coexistence of native European crayfish with this pathogen, and further research is now needed to identify the key mechanisms allowing it. 相似文献
106.
The in vitro cytotoxic potentials of Furo[3,2-c]pyran-4-one derivatives in human lymphocytes were investigated. Blood samples were obtained from six healthy donors, non-smoking
volunteers, which were incubated and exposed to increasing concentrations (0.05, 0.1, 0.5, 1 and 2 mg/mL) of Furo[3,2-c]pyran-4-one derivatives which are methyl 2-methoxy-7-(4-methylbenzoyl)-6-(4-methylphenyl)-4-oxo-4H-furo[3,2-c]pyran-3-carboxylate (1a) and methyl 2-methoxy-7-(4-methoxybenzoyl)-6-(4-methoxyphenyl)-4-oxo-4H-furo[3,2-c]pyran-3-carboxylate (1b). Compounds 1a and 1b induced micronucleus, mitotic and replication indexes in human lymphocytes
(1 and 2 mg/mL). The increases of micronucleus, mitotic and replication indexes show that compounds at high concentrations
may become cytotoxic, genotoxic and carcinogenic. 相似文献
107.
Teucrium montanum L. and T. polium L. are the two closest Teucrium L. species from sect. Polium (Mill.) Schreb in Turkey. In addition, they are sympatric for some part of their range in Turkey. In this study, comparative
anatomical and micromorphological studies of the two species are carried out. They have been investigated by their leaf and
stem anatomical features, as well as nutlet micromorphological characteristics. The results of anatomical studies show that
the anatomical characters of both taxa are observed to be similar to the general features of the family Lamiaceae anatomy,
except for lacking rich collenchyma at the corners. Both taxa are similar in stem anatomy and their leaves exhibit xeromorphy.
However, trichome morphology on the stems and the leaves appear to have a taxonomic value in segregation of the two taxa.
Light and scanning electron microscope studies on the nutlets also show that nutlet shapes, measures and surface micromorphologies
are different in the two species. Whereas nutlet surfaces are bireticulate in both species, the nutlets are larger and primary
sculpturing is more distinct in T. polium than in T. montanum. Moreover, the nutlets are oblong to oblong-ovoid and larger in T. polium, but ovoid and smaller in T. montanum. 相似文献
108.
Baak Koca
zer 《Economics & Human Biology》2007,5(2):280-301
The purpose of the study is to develop current reference growth centiles for Turkish children and adolescents. A cross-sectional growth survey was conducted on 1.427 (709 boys and 718 girls) healthy schoolchildren aged 6-17 years in Ankara, the capital city of Turkey. As an indicator of socio-economic status, the occupation of the parents was recorded. Growth references of height, weight, body mass index (BMI), sitting height, iliospinal height, relative iliospinal height and relative sitting height were constructed by the LMS method. Sex differences, association of parental occupation with height and BMI standard deviation scores were assessed by analyses of variance. Results showed significant sexual dimorphism for height, weight, sitting height and iliospinal height (p<0.001). Significant effect of socio-economic background was found on height and BMI. The prevalence of overweight and obesity was found using the International Obesity Task Force (IOTF) reference criteria 22.4% and 5.6% in boys and 21.2% and 3% in girls. Present results demonstrated an increment during the last three decades in height, leg length and weight curves which is more prominent in boys, but not in the sitting height. This positive secular change appears to be a logical outcome of the gradual changes in nutrition, health care and education, and environmental and economic conditions. 相似文献
109.
We present the results of a series of 10-ns molecular dynamics simulations on Pseudomonas aeruginosa lectin-II (PA-IIL) and its complexes with four different monosaccharides. We compare the saccharide-free, saccharide-occupied, and saccharide- and ion-free forms of the lectin. The results are coupled with analysis of the water density map and calcium coordination. The water density pattern around the binding site in the free lectin molecular dynamics was fitted with that in the X-ray and with the hydroxyl groups of the monosaccharide within the lectin/monosaccharide complexes and the best ligand was predicted based on the best fit. Interestingly, the water density pattern around the binding site in the uncomplexed lectin exactly fitted the O2, O3, and O4 hydroxyl groups of the fucose complex with the lectin. This observation could lead to a hypothesis that the replacement of these three water molecules from the binding site by the monosaccharide decreases the entropy of the complex and increases the entropy of the water molecules, which favors the binding. It suggests that the high density peaks of the solvent around the binding site in the free protein could be the tool to predict hydroxyl group orientation of the sugar in the protein/sugar complexes. The high affinity of PA-IIL binding site is also attributed to the presence of two calcium ions, each of them making five to six coordinations with the protein part and two coordinations with either water or the monosaccharide. When the calcium ions are removed from the simulated system, they are replaced by sodium ions from the solvent. These observations rationalize the high binding affinity of PA-IIL towards fucose. 相似文献
110.
Iron (Fe) deficiency is increasingly being observed in cropping systems with frequent glyphosate applications. A likely reason for this is that glyphosate interferes with root uptake of Fe by inhibiting ferric reductase in roots required for Fe acquisition by dicot and nongrass species. This study investigated the role of drift rates of glyphosate (0.32, 0.95 or 1.89 mm glyphosate corresponding to 1, 3 and 6% of the recommended herbicidal dose, respectively) on ferric reductase activity of sunflower (Helianthus annuus) roots grown under Fe deficiency conditions. Application of 1.89 mm glyphosate resulted in almost 50% inhibition of ferric reductase within 6 h and complete inhibition 24 h after the treatment. Even at lower rates of glyphosate (e.g. 0.32 mm and 0.95 mm), ferric reductase was inhibited. Soluble sugar concentration and the NAD(P)H oxidizing capacity of apical roots were not decreased by the glyphosate applications. To our knowledge, this is the first study reporting the effects of glyphosate on ferric reductase activity. The nature of the inhibitory effect of glyphosate on ferric reductase could not be identified. Impaired ferric reductase could be a major reason for the increasingly observed Fe deficiency in cropping systems associated with widespread glyphosate usage. 相似文献