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91.
WANG Lingling* MA Li * LENG Wenchuan YANG Jian ZHU Junping DONG Jie XUE Ying WAN Zhe LI Ruoyu & JIN Qi . State Key Laboratory For Molecular Virology Genetics Engineering Beijing China . Chinese National Human Genome Center Beijing Beijing China . Research Centre for Medical Mycology Beijing China 《中国科学:生命科学英文版》2004,47(5):389-395
Superficial fungi are the etiologic pathogens of various dermatophytoses, such as tinea capitis, tinea corporis, tinea inguinalis, tinea manus, tinea unguium and tinea pedis. These widespread infections affect up to 25% of the worlds population, a percentage that has continued to increase in recent years. T. rubrum is the most common superficial fungus, accounting for at least 60% of all infections of this type. T. rubrum can induce dermatophytoses in different parts of the hu-man skin, and ca… 相似文献
92.
As a large family of hydrolases, GTPases are widespread in cells and play the very important biological function of hydrolyzing GTP into GDP and inorganic phosphate through binding with it. GTPases are involved in cell cycle regulation, protein synthesis, and protein transportation. Chaperones can facilitate the folding or refolding of nascent peptides and denatured proteins to their native states. However, chaperones do not occur in the native structures in which they can perform their normal biological functions. In the current study, the chaperone activity of the conserved GTPases of Escherichia coli is tested by the chemical denaturation and chaperone-assisted renaturation of citrate synthase and α-glucosidase. The effects of ribosomes and nucleotides on the chaperone activity are also examined. Our data indicate that these conserved GTPases have chaperone properties, and may be ancestral protein folding factors that have appeared before dedicated chaperones. 相似文献
93.
The effect of antibacterial peptide CM4 of Bombyx mori against E. coli K12 was investigated using scanning electron microscopy(SEM) and transmission electron microscopy (TEM). The ultrastructural changes of E. coli K12 were observed by the challenge of the purified antibacterial peptide CM4. The results showed that the antibacterial peptide caused a series of pathological changes on E. coli. SEM and TEM revealed aggregates of bacteria and SEM revealed wrinkled bacterial surfaces in the early stage. Thereafter, plasmolysis was observed with irregular holes appearing in the two ends of bacteria and the cytoplasmic contents of the cells leaking out. Finally, bacteria became empty vesicles and disintegrated into small fragments subsequently. Comparatively, the bacterial membrane was normal and the bacterial structure remained intact in the control group. 相似文献
94.
Xiaoli Shi Xiyin Wang Zhe Li Qihui Zhu Ji Yang Song Ge Jingchu Luo 《植物学报(英文版)》2007,49(9):1393-1399
Cereal genes are classified into two distinct classes according to the guanine-cytosine (GC) content at the third codon sites (GC3). Natural selection and mutation bias have been proposed to affect the GC content. However, there has been controversy about the cause of GC variation. Here, we characterized the GC content of 1 092 paralogs and other single-copy genes in the duplicated chromosomal regions of the rice genome (ssp. indica) and classified the paralogs into GC3-rich and GC3-poor groups. By referring to out-group sequences from Arabidopsis and maize, we confirmed that the average synonymous substitution rate of the GC3-rich genes is significantly lower than that of the GC3-poor genes. Furthermore, we explored the other possible factors corresponding to the GC variation including the length of coding sequences, the number of exons in each gene, the number of genes in each family, the location of genes on chromosomes and the protein functions. Consequently, we propose that natural selection rather than mutation bias was the primary cause of the GC variation. 相似文献
95.
中国人肤纹研究 Ⅰ.汉族10项肤纹参数正常值的测定 总被引:15,自引:2,他引:15
我们的祖先对指纹早有观察,新石器时代陶器上的雷云纹即由指纹脱胎而来。在近代科学中,Galton(1892)首先提出指纹的系统分类。尔后Cummins等修订了肤纹分析方法。肤纹分析在医学上的应用首推Cummins,他最早描述了先天愚型患儿的肤纹特征。迄今大量的材料表明,异常肤纹组合可作为某些遗传病的辅助诊断指标。对我国人群的肤纹参数正常值,1933年Takeya曾有报道,近年来董悌忱、李崇高和王京美等人也进行了这方面的工作,但尚缺乏比较全面的肤纹参数正常值。本文报道1,040例汉族人10项肤纹参数正常值,为医学肤纹学和人类学研究提供基础数据。 相似文献
96.
97.
LIANG Hui CHEN Hankui SHEN Yayun FENG Qisheng JIN Wei HUANG Wei & ZENG Yixin . Cancer Center Sun Yat-sen University Guangzhou China . Chinese National Human Genome Center at Shanghai Shanghai China 《中国科学:生命科学英文版》2004,47(5):449-453
Nasopharyngeal carcinoma (NPC) is an endemic cancer with geographic and ethnic distribution within southern China and southeastern Asia, particularly in the delta area of Pearl River in Guangdong Province, where the incidence is up to 10 to 30/100000 per year. Epidemiological studies have demonstrated that the involvement of genetic factors along with Epstein- Barr virus (EBV) infections and other environmental factors are contributing to the pathogenesis of this disease in the area with … 相似文献
98.
99.
Diversity and phylogeny of bacteria on Zimbabwe tobacco leaves estimated by 16S rRNA sequence analysis 总被引:1,自引:0,他引:1
Microorganisms play important roles in the tobacco aging process. However, microbial communities on flue-cured tobacco leaves
(FCTL) remain largely unknown. In this study, the total microbial genomic DNA of unaged and aging FCTL from Zimbabwe were
isolated using a culture-independent method, and the bacterial communities were investigated through analyzing two 16S rRNA
gene libraries. Eighty-four and 65 operational taxonomic units were obtained from the libraries of the unaged and aging FCTL,
respectively. The following genera were represented more than 4% in both libraries (aging and unaged library): Sphingomonas (4.84%, 4.18%), Stenotrophomonas (4.84%, 5.23%), Erwinia (5.81%, 4.88%), Pantoea (19.35%, 18.47%), and Pseudomonas (21.29%, 24.04%). The dominant species varied between the two libraries. Specifically, several dominant species in unaged
FCTL including Pseudomonas fulva, Pseudomonas sp. (AM909658), Klebsiella sp. (HM584796), and Pantoea sp. (AY501386) were not identified in aging FCTL, while several dominant species in aging FCTL such as Pantoea sp. (GU566350), Pseudomonas sp. (EF157292), and Buttiauxella izardii were not found in unaged FCTL. The phylogenetic analysis showed that bacteria from unaged and aging FCTL were divided into
two clades, and two unique subclades were identified in aging FCTL. Our results revealed for the first time the bacterial
diversities on Zimbabwe tobacco, and provided a basis for clarifying the roles of bacteria in aging process of FCTL. 相似文献
100.
YONG LI JIAN-FENG LU CONG-JING FENG XIN KE WEN-JUN FU 《Insect Science》2007,14(2):93-100
Venom and ovarian proteins in braconid and ichneumonid wasps play an important role in the successful parasitism of their host, especially for immune suppression immediately after oviposition. In this study, we compared the effect of venom and ovarian proteins collected from the female wasps of Macrocentrus cingulum, a polyembryonic parasitoid of the larvae of Ostriniafunacalis, on the encapsulation capacity of Sephadex A- 25 beads at 4 h and 24 h post-injection both in vivo and in vitro. The results showed that the ovarian proteins significantly interfered with the encapsulation capacity of hemocytes in a dose-dependent manner. Spreading and viability of hemocytes in O. furnacalis was not disrupted by venom and ovarian proteins at various concentrations injected. It seems likely that the ovarian proteins from M. cingulum play a role in suppressing the encapsulation capacity of host hemocytes. 相似文献