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91.
The F plasmid carries an IS3 insertion within finO 总被引:4,自引:0,他引:4
DNA-DNA hybridization studies support the conclusion that coding sequences of the fertility inhibition gene, finO, are present on the F plasmid and map downstream of the transfer region, entirely within 99.19-2.0 F. In addition, the results indicate that the IS3a element at 100/0-1.26 F is inserted within the F finO coding region. This insertion may have inactivated the finO gene on the F plasmid. 相似文献
92.
Relative predispositional effects (RPEs) of marker alleles with disease: HLA-DR alleles and Graves disease. 总被引:8,自引:3,他引:5 下载免费PDF全文
H Payami S Joe N R Farid V Stenszky S H Chan P P Yeo J S Cheah G Thomson 《American journal of human genetics》1989,45(4):541-546
A method is described to reveal the relative predispositional effects (RPEs) (predisposing, protective, or neutral) of the HLA alleles or of any other marker system that is associated with a disease. When the disease is associated with two or more alleles of a locus, the RPE method identifies the associations sequentially according to their strength; thus the problem that a strong association with one allele can create misleading deviations in the frequencies of other alleles is alleviated. Using this method, we have examined the relative effects of HLA-DR alleles in susceptibility to Graves disease in the Caucasian population. The well-established positive association with DR3 was confirmed as the strongest effect. In addition, a negative association was found between DR5 and Graves disease. The reduced frequency of DR5 among patients is statistically significant and is not a result of the increase in DR3. Finally, when patients were divided according to the presence or absence of eye disease, the latter showed a significant increase in the frequency of DR4. With family data, linkage to HLA of Graves disease was established in both Caucasian and Chinese families by the sib-pair method. 相似文献
93.
94.
NO Agbenin AM Emechebe PS Marley 《Archives Of Phytopathology And Plant Protection》2013,46(4):319-326
Fusarium wilt and root-knot are important diseases of tomato. The use of chemical is becoming less appealing because of the health implications. Also, the chemicals required are often not within the reach of farmers in most of the developing part of the world. This research is aimed at finding an alternative mode of control. Tomato variety Roma VF inoculated with Meloidogyne and Fusarium were treated with 2 g/kg soil neem seed powder in the screenhouse and 2 Mg ha ? 1 in the field. An untreated and Furadan treated plot in the field served as control. Neem seed powder significantly reduced the disease severity of Fusarium and root-knot in both screenhouse and field. Results suggest the possible use of neem seed powder for control of the root-knot nematodes - Fusarium wilt disease complex. 相似文献
95.
Background
In the past years the Smith-Waterman sequence comparison algorithm has gained popularity due to improved implementations and rapidly increasing computing power. However, the quality and sensitivity of a database search is not only determined by the algorithm but also by the statistical significance testing for an alignment. The e-value is the most commonly used statistical validation method for sequence database searching. The CluSTr database and the Protein World database have been created using an alternative statistical significance test: a Z-score based on Monte-Carlo statistics. Several papers have described the superiority of the Z-score as compared to the e-value, using simulated data. We were interested if this could be validated when applied to existing, evolutionary related protein sequences. 相似文献96.
Background
It is widely accepted that genetic regulatory systems are 'modular', in that the whole system is made up of smaller 'subsystems' corresponding to specific biological functions. Most attempts to identify modules in genetic regulatory systems have relied on the topology of the underlying network. However, it is the temporal activity (dynamics) of genes and proteins that corresponds to biological functions, and hence it is dynamics that we focus on here for identifying subsystems. 相似文献97.
S-nitrosylated GAPDH initiates apoptotic cell death by nuclear translocation following Siah1 binding 总被引:10,自引:0,他引:10
Hara MR Agrawal N Kim SF Cascio MB Fujimuro M Ozeki Y Takahashi M Cheah JH Tankou SK Hester LD Ferris CD Hayward SD Snyder SH Sawa A 《Nature cell biology》2005,7(7):665-674
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) influences cytotoxicity, translocating to the nucleus during apoptosis. Here we report a signalling pathway in which nitric oxide (NO) generation that follows apoptotic stimulation elicits S-nitrosylation of GAPDH, which triggers binding to Siah1 (an E3 ubiquitin ligase), nuclear translocation and apoptosis. S-nitrosylation of GAPDH augments its binding to Siah1, whose nuclear localization signal mediates translocation of GAPDH. GAPDH stabilizes Siah1, facilitating its degradation of nuclear proteins. Activation of macrophages by endotoxin and of neurons by glutamate elicits GAPDH-Siah1 binding, nuclear translocation and apoptosis, which are prevented by NO deletion. The NO-S-nitrosylation-GAPDH-Siah1 cascade may represent an important molecular mechanism of cytotoxicity. 相似文献
98.
Chai-Hoon Khoo Yoke-Kqueen Cheah Learn-Han Lee Jiun-Horng Sim Noorzaleha Awang Salleh Shiran Mohd Sidik Son Radu Sabrina Sukardi 《Antonie van Leeuwenhoek》2009,96(4):441-457
The increased occurrence of Salmonella occurrence in local indigenous vegetables and poultry meat can be a potential health hazards. This study is aimed to detect
the prevalence of twenty different virulence factors among Salmonella enterica strains isolated from poultry and local indigenous vegetables in Malaysia via an optimized, rapid and specific multiplex
PCR assay. The assay encompasses a total of 19 Salmonella pathogenicity islands genes and a quorum sensing gene (sdiA) in three multiplex reaction sets. A total of 114 Salmonella
enterica isolates belonging to 38 different serovars were tested. Each isolate in under this study was found to possess up to 70%
of the virulence genes tested and exhibited variable pathogenicity gene patterns. Reproducibility of the multiplex PCR assay
was found to be 100% and the detection limit of the optimized multiplex PCR was tested with lowest detectable concentration
of DNA 0.8 pg μl−1. This study demonstrated various Salmonella pathogenicity island virulence gene patterns even within the same serovar. This sets of multiplex PCR system provide a fast
and reliable typing approach based on Salmonella pathogenicity islands, thus enabling an effective monitoring of emerging pathogenic Salmonella strains as an additional tool in Salmonella surveillance studies. 相似文献
99.
100.
The effect of trifluoperazine on the respiration of porcine liver and skeletal muscle mitochondria was investigated by polarographic and spectroscopic techniques. Low concentrations of trifluoperazine (88 nmol/mg protein) inhibited both the ADP- and Ca2+-stimulated oxidation of succinate, and reduced the values of the respiratory control index and the and ratio. High concentrations inhibited both succinate and ascorbate plus tetramethyl-p-phenylenediame (TMPD) oxidations, and uncoupler (carbonyl cyanide p-trifluromethoxyphenylhydrazone) and Ca2+-stimulated respiration. Porcine liver mitochondria were more sensitive to trifluoperazine than skeletal muscle mitochondria. Trifluoperazine inhibited the electron transport of succinate oxidation of skeletal muscle mitochondria within the cytochrome b-c1 and cytochrome c1-aa3 segments of the respiratory chain system. 233 nmol trifluoperazine/mg protein inhibited the aerobic steady-state reduction of cytochrome c1 by 92% with succinate as substrate, and of cytochrome c and cytochrome aa3 by 50–60% with ascorbate plus TMPD as electron donors. Trifluoperazine can thus inhibit calmodulin-independent reactions particularly when used at high concentrations. 相似文献