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81.
On the patterns of abundance and diversity of macrolichens of Chopta-Tunganath in the Garhwal Himalaya 总被引:1,自引:0,他引:1
Negi HR 《Journal of biosciences》2000,25(4):367-378
A total of 3211 colonies of macrolichens, from twelve 50 m × 10 m plots distributed across four macrohabitat (vegetation)
types between 1500 m–3700 m in the Chopta-Tunganath landscape of the Garhwal Himalaya, yielded 13 families with 15 genera
and 85 species.Lobaria retigera stood out as a broad-niched generalist species with moderate levels of abundance in all the three major microhabitats, viz.
rock, soil and wood across 83% of all the plots sampled, whereasUmbilicaria indica emerged as an abundantly occurring specialist confined to rock substrates.Heterodermia incana andLeptogium javanicum appeared to be rare members of the community as they were encountered only once during the field survey. Woody microhabitats
turned out to be richer than rock and soil substrates for macrolichens. Amongst the macrohabitats, middle altitude (2500–2800
m)Quercus forest was richest in species and genera followed by high altitude (2900–3200 m)Rhododendron forest, higher altitude grasslands (3300–3700 m) and then the lower elevation (1500 m)Quercus forest. Species, genus and family level alphaas well as beta-diversities were significantly correlated with each other, implying
that higher taxonomic ranks such as genera may be used as surrogates for species thus facilitating cost- and time-effective
periodic monitoring of the biodiversity of macrolichens. Dynamics of the diversity of lichen communities in relation to various
forms of environmental disturbance including livestock grazing and tourism as dominant land use activities in the higher Himalaya
need further research. 相似文献
82.
83.
CC chemokine receptor 2 expression in donor cells serves an essential role in graft-versus-host-disease 总被引:5,自引:0,他引:5
Rao AR Quinones MP Garavito E Kalkonde Y Jimenez F Gibbons C Perez J Melby P Kuziel W Reddick RL Ahuja SK Ahuja SS 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(9):4875-4885
The complete repertoire of cellular and molecular determinants that influence graft-vs-host disease (GVHD) is not known. Using a well-established murine model of GVHD (B6-->bm12 mice), we sought to elucidate the role of the donor non-T cell compartment and molecular determinants therein in the pathogenesis of GVHD. In this model the acute GVHD-inducing effects of purified B6 wild-type (wt) CD4(+) T cells was inhibited by wt non-T cells in a dose-dependent manner. Paradoxically, unlike the chronic GVHD phenotype observed in bm12 mice transplanted with B6wt unfractionated splenocytes, bm12 recipients of B6ccr2-null unfractionated splenocytes developed acute GVHD and died of IFN-gamma-mediated bone marrow aplasia. This switch from chronic to acute GVHD was associated with increased target organ infiltration of activated CD4(+) T cells as well as enhanced expression of Th1/Th2 cytokines, chemokines, and the antiapoptotic factor bfl1. In vitro, ccr2(-/-) CD4(+) T cells in unfractionated splenocytes underwent significantly less activation-induced cell death than B6wt CD4(+) T cells, providing another potential mechanistic basis along with enhanced expression of bfl1 for the increased numbers of activated T cells in target organs of B6ccr2(-/-) splenocyte-->bm12 mice. Collectively, these findings have important clinical implications, as they implicate the donor non-T cell compartment as a critical regulator of GVHD and suggest that ccr2 expression in this cellular compartment may be an important molecular determinant of activation-induced cell death and GVHD pathogenesis. 相似文献
84.
Kato M Khan S Gonzalez N O'Neill BP McDonald KJ Cooper BJ Angel NZ Hart DN 《The Journal of biological chemistry》2003,278(36):34035-34041
85.
Different concentrations of ammonium molybdate (10(-7) to 10(-4)M) affected the levels of metabolites in the source and sink organs of the seedlings of C. melo and C. vulgaris and data were recorded at 7, 14 and 21 days after treatment (DAT) of molybdenum (Mo). Reducing and non reducing sugars declined with an increase in concentration of ammonium molybdate from 10(-7) to 10(-4) M. Soluble protein and dry weight of seedlings increased in source at lower concentration (10(-7) M) and gradually decreased in all other concentrations (10(-6), 10(-5) and 10(-4) M). Starch was slightly accumulated in hypocotyl and fresh weight constantly declined with an increase in ammonium molybdate concentration from 10(-7) to 10(-4) M in all the parts of seedlings viz. cotyledon, hypocotyl and roots. Thus molybdenum at higher concentration induced decline in the metabolite levels in source and sink as well as in transporting organs. 相似文献
86.
Moritz Menzel Diana Meckbach Benjamin Weide Nora C. Toussaint Karin Schilbach Seema Noor Thomas Eigentler Kristian Ikenberg Christian Busch Leticia Quintanilla‐Martinez Ursula Kohlhofer Antonia Göke Friederike Göke Rupert Handgretinger Christian Ottmann Boris C. Bastian Claus Garbe Martin Röcken Sven Perner Oliver Kohlbacher Jürgen Bauer 《Pigment cell & melanoma research》2014,27(4):671-673
87.
Andrea Slusser Chandra S. Bathula Donald A. Sens Seema Somji Mary Ann Sens Xu Dong Zhou Scott H. Garrett 《PloS one》2015,10(3)
Background
Cultures of human proximal tubule cells have been widely utilized to study the role of EMT in renal disease. The goal of this study was to define the role of growth media composition on classic EMT responses, define the expression of E- and N-cadherin, and define the functional epitope of MT-3 that mediates MET in HK-2 cells.Methods
Immunohistochemistry, microdissection, real-time PCR, western blotting, and ELISA were used to define the expression of E- and N-cadherin mRNA and protein in HK-2 and HPT cell cultures. Site-directed mutagenesis, stable transfection, measurement of transepithelial resistance and dome formation were used to define the unique amino acid sequence of MT-3 associated with MET in HK-2 cells.Results
It was shown that both E- and N-cadherin mRNA and protein are expressed in the human renal proximal tubule. It was shown, based on the pattern of cadherin expression, connexin expression, vectorial active transport, and transepithelial resistance, that the HK-2 cell line has already undergone many of the early features associated with EMT. It was shown that the unique, six amino acid, C-terminal sequence of MT-3 is required for MT-3 to induce MET in HK-2 cells.Conclusions
The results show that the HK-2 cell line can be an effective model to study later stages in the conversion of the renal epithelial cell to a mesenchymal cell. The HK-2 cell line, transfected with MT-3, may be an effective model to study the process of MET. The study implicates the unique C-terminal sequence of MT-3 in the conversion of HK-2 cells to display an enhanced epithelial phenotype. 相似文献88.
Shyam Sundar Sharma Md Aminul Islam Anoop Anand Malik Kamlesh Kumar Madan Singh Negi Shashi Bhushan Tripathi 《Physiology and Molecular Biology of Plants》2016,22(2):193-205
Phenotypic variation of important seed traits like seed length, seed breadth, seed thickness, 100 seed weight and seed oil content were recorded in a total of 157 collected accessions of Pongamia. Out of these, fatty acid profiles of 38 accessions selected based on their high and low oil content was analyzed. Fatty acid profile revealed high variability in stearic, oleic and linoleic acid which varied from 0.42 to 10.61 %, 34.34 to 74.58 %, and 7.00 to 31.28 % respectively. Variations in palmitic and linolenic acid were small. Iodine value, saponification number and cetane number (CN) of fatty acid methyl esters (FAME) of seed oil ranges from 186.99 to 201.25, 81.13 to 108.19 and 46.16 to 56.47 respectively. Fatty acid compositions, degree of unsaturation and CN are the important parameters, which are used to determine quality of FAME were used as biodiesel. Some of the Pongamia accessions identified were higher in oil content while some accessions showed higher degree of unsaturation and a few of them had CN values higher than 55. Genetic diversity analysis with six TE-AFLP primers generated a total of 334 bands out of which 174 (52.10 %) were polymorphic. The genetic similarity ranged from 0.11 to 0.47. These findings clearly showed high level of genetic diversity and all economically desirable traits were not present in a single genotype of Pongamia. All these traits could be selected from these CPTs and transfer to a single elite variety through selection and breeding programme and could be utilized for large scale multiplication and plantation to produce high quantity and quality biodiesel in future. 相似文献
89.
Gupta DK Shah P Misra A Bharadwaj S Gulati S Gupta N Sharma R Pandey RM Goel K 《PloS one》2011,6(2):e17221
The present study examines the secular trends in prevalence of overweight and obesity among urban Asian Indian adolescents in New Delhi (North India). The data were derived from cross-sectional sampling of children, 3493 in year 2006 and 4908 in year 2009, aged 14-17 years studying in privately-funded and government-funded schools. Age, gender and Asian Indian-specific cut offs of body mass index (BMI) were used to define overweight and obesity. The prevalence of obesity increased significantly from 9.8% in 2006 to 11.7% in 2009 (p<0.01), whereas underweight decreased from 11.3% to 3.9% (p<0.001). There was a significantly higher risk of being overweight (OR 1.28; 95% CI, 1.15-1.42) and obese (OR 1.44; 95% CI, 1.24-1.66) in year 2009 than 2006, after adjusting for age, gender and type of school. Males and privately-funded school children had significantly higher increase in prevalence and risk of being overweight and obese over the three years. In conclusion, this study showed an increasing trend in prevalence of overweight and obesity in urban Asian Indian adolescents. More specifically, the study showed the association of this increasing trend of overweight and obesity prevalence with male gender and high socio-economic status, calling for an urgent need for immediate and targeted preventive measures. 相似文献
90.