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11.
Kamal Laina Zarisa Mohd Adam Mowaffaq Adam Ahmed Shahpudin Siti Nurfatimah Mohd. Shuib Ahmad Naqeeb Sandai Rosline Hassan Norazian Mohd Tabana Yasser Basri Dayang Fredalina Than Leslie Thian Lung Sandai Doblin 《Mycopathologia》2021,186(2):221-236
Mycopathologia - Candida albicans has been reported globally as the most widespread pathogenic species contributing candidiasis from superficial to systemic infections in immunocompromised... 相似文献
12.
The effect of lincocin (a plastid protein synthesis inhibitor) treatment on the greening process of bean (Phaseolus vulgaris L.) leaves have been studied. In comparison with control leaves treated ones had a decreased rate of chloroplast development. They had a marked chlorophyll deficiency and a decreased chlorophyll a/b ratio. Some long and short wavelength forms of chlorophyll a were lacking as evidenced from the absorption spectra at 25°C and the fluorescence spectra at 77°K. The –14CO2 fixation was inhibited by 80–90% in treated leaves. The fluorescence induced by the measuring light was greater in the treated leaves than in the control ones, and the kinetics of the decline of the relative fluorescence intensity were also different. Electron microscopic studies showed macrogranum-like structures and incomplete membrane vesicles in the treated plastids. After longer treatment a destruction of membranes was observed. The results indicate some structural and functional membrane deficiencies and instability of the membranes. 相似文献
13.
为探讨细胞因子基因(人IL-2、IL-6)转导对于肿瘤细胞膜MHC抗原及细胞膜糖蛋白表达调控的影响,本文利用脂质体介导的方法,将含人IL-6、IL-2基因的逆转录病毒载体分别导入人乳腺癌细胞系MCF-7细胞中,采用间接免疫荧光染色流式细胞仪测定法,对基因转导的瘤细胞细胞膜糖蛋白及MHC抗原表达进行测定。结果表明经两种基因修饰的MCF-7细胞MHCⅠ型抗原表达均获得增强,此外,基因转导细胞可程度不同地表现出细胞膜多种糖蛋白表达的变化。提示肿瘤细胞膜抗原及糖蛋白表达的改变可能是细胞因子基因转导影响肿瘤细胞免疫原性的重要结构基础。 相似文献
14.
STEPHEN F. NG 《The Journal of eukaryotic microbiology》1989,36(1):74-81
Removal of the micronuclei of Paramecium tetraurelia and Paramecium jenningsi by micropipetting generates amicronucleate cell lines. These cell lines go through a period of growth depression for several dozen fissions, but they gradually recover. Amicronucleate cells in the depression period characteristically exhibit abnormal oral development, particularly reduction in the length of the buccal cavity and an abnormal pattern of the oral membranelles. To test the notion that the macronucleus is involved in the recovery of amicronucleate cell lines, DNA demethylation drugs were administered to amicronucleates in the depression period. After at least 4 fissions, the treated amicronucleates were assessed for their progress in recovery by scoring the proportion of cells with normal oral membranelles. Cvtidine analogues which demethylate cytosine specifically at the 5 position, namely 5-azacytidine, 5-aza-2'- deoxycytidine and 5-fluoro-2'-deoxycytidine. promoted recovery of the amicronucleates. Cytidine, 6-azacytidine, 2'-fluoro-2'-deoxy-cytidine and cytosine-β-D-arabinofuranoside did not. These results suggest that (i) 5-methylcytosine is present in the macronucleus of these Paramecium species, probably in small amounts and (ii) recovery of amicronucleates involves demethylation of macronuclear DNA. This implies that in normal cells the micronuclei are involved in maintaining the macronuclear DNA in a methylated state and hence the inactivation of the macronuclear sequences that are to be employed for stomatogenic recovery. A general mechanism for the control of gene expression may therefore be employed for the regulation of specific sequences. 相似文献
15.
16.
Aung Than Melvin Khee-Shing Leow Peng Chen 《The Journal of biological chemistry》2013,288(22):15520-15531
Angiotensin II (AngII), a peptide hormone released by adipocytes, can be catabolized by adipose angiotensin-converting enzyme 2 (ACE2) to form Ang(1–7). Co-expression of AngII receptors (AT1 and AT2) and Ang(1–7) receptors (Mas) in adipocytes implies the autocrine regulation of the local angiotensin system upon adipocyte functions, through yet unknown interactive mechanisms. In the present study, we reveal the adipogenic effects of Ang(1–7) through activation of Mas receptor and its subtle interplays with the antiadipogenic AngII-AT1 signaling pathways. Specifically, in human and 3T3-L1 preadipocytes, Ang(1–7)-Mas signaling promotes adipogenesis via activation of PI3K/Akt and inhibition of MAPK kinase/ERK pathways, and Ang(1–7)-Mas antagonizes the antiadipogenic effect of AngII-AT1 by inhibiting the AngII-AT1-triggered MAPK kinase/ERK pathway. The autocrine regulation of the AngII/AT1-ACE2-Ang(1–7)/Mas axis upon adipogenesis has also been revealed. This study suggests the importance of the local regulation of the delicately balanced angiotensin system upon adipogenesis and its potential as a novel therapeutic target for obesity and related metabolic disorders. 相似文献
17.
18.
C. T. LEE S. L. LEE Q. Z. FARIDAH S. S. SIRAJ K. K. S. NG B. NORLIA M. N. MAT‐ISA 《Molecular ecology resources》2006,6(4):1198-1201
This paper reports the isolation and characterization of 24 polymorphic microsatellite markers in an important tropical timber species, Koompassia malaccensis (Leguminosae). The primers were designed from a genomic library enriched for dinucleotide (CT) repeats and screened on 24 samples from a natural population. The number of alleles detected per locus ranged from two to 13 while the observed heterozygosity ranged from 0.042 to 1.000. Significant departure from Hardy–Weinberg equilibrium (P < 0.05) was detected in two loci. These microsatellite markers were tested across 13 timber species of the same family. The amplification success appeared to be associated with taxonomy classification at the genus but not subfamily levels. 相似文献
19.
Renying Wang Peijing Zhang Jingjing Wang Lifeng Ma Weigao E Shengbao Suo Mengmeng Jiang Jiaqi Li Haide Chen Huiyu Sun Lijiang Fei Ziming Zhou Yincong Zhou Yao Chen Weiqi Zhang Xinru Wang Yuqing Mei Zhongyi Sun Chengxuan Yu Jikai Shao Yuting Fu Yanyu Xiao Fang Ye Xing Fang Hanyu Wu Qile Guo Xiunan Fang Xia Li Xianzhi Gao Dan Wang Peng-Fei Xu Rui Zeng Gang Xu Lijun Zhu Lie Wang Jing Qu Dan Zhang Hongwei Ouyang He Huang Ming Chen Shyh-Chang NG Guang-Hui Liu Guo-Cheng Yuan Guoji Guo Xiaoping Han 《Nucleic acids research》2023,51(2):501
Individual cells are basic units of life. Despite extensive efforts to characterize the cellular heterogeneity of different organisms, cross-species comparisons of landscape dynamics have not been achieved. Here, we applied single-cell RNA sequencing (scRNA-seq) to map organism-level cell landscapes at multiple life stages for mice, zebrafish and Drosophila. By integrating the comprehensive dataset of > 2.6 million single cells, we constructed a cross-species cell landscape and identified signatures and common pathways that changed throughout the life span. We identified structural inflammation and mitochondrial dysfunction as the most common hallmarks of organism aging, and found that pharmacological activation of mitochondrial metabolism alleviated aging phenotypes in mice. The cross-species cell landscape with other published datasets were stored in an integrated online portal—Cell Landscape. Our work provides a valuable resource for studying lineage development, maturation and aging. 相似文献
20.
Dharap AS Sharma HS Than M 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2000,58(3):309-315
The incidence of ear lobe crease (ELC) was studied in 1576 healthy Malay subjects (566 males and 1010 females), randomly selected from the residents of Kota Bharu, Malaysia. ELC was present in 31.1% of males and in 3.6% of females; this difference in incidence between the two sexes is statistically significant (p > 0.05). In males the incidence of Type I crease was highest (10.1%) while that of Type III crease was lowest (2.3%). In females Type II crease showed the highest incidence (1.9%) and Type III the lowest. The incidence of bilateral presence of all three types of ELC showed an age-related increase in males. The ELC often starts unilaterally and later develops bilaterally and earlier in males than in females. 相似文献