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961.
The nucleocaPsid Protein (49 Kd) of vesicular stomatitis virus is tightly bound to the genome rendering the latter transcriPtionally
comPetent. Controlled digestion with chymotryPsin removed a 12 Kd PePtide from the comPlex. The resulting comPlex failed to
serve as temPlate for genome transcriPtionin vitro when the Polymerase comPonents L and NS Proteins were added. A temPlate-associated Protein kinase activity was also lost
uPon chymotryPsin treatment. However, the cleaved nucleocaPsid Protein (37 Kd) was still caPable of binding tightly with the
genome temPlate and retained the ePitoPe recognized by a monoclonal antibody. These results suggest that the nucleocaPsid
Protein Possesses seParate domains that mediate binding to Polymerase comPlex and maintain the structural integrity of the
template. 相似文献
962.
963.
A Krarup P Chattopadhyay A K Bhattacharjee J R Burge G R Ruble 《Laboratory animal science》1999,49(5):545-550
BACKGROUND AND PURPOSE: When evaluating vaccines for efficacy against gram-negative endotoxemia, the challenge has historically required death of a large percentage of test subjects. We attempted to identify surrogate markers of impending death to allow for early euthanasia without interfering with experimental data collection. METHODS: Galactosamine-sensitized mice (n = 140) were inoculated intraperitoneally with various dosages of endotoxin, and development of clinical signs of disease--body temperature, body weight, hunched posture, ruffled coat, inability to ambulate, and loss of consciousness--was evaluated. RESULTS: Wide fluctuations in body temperature (+/- 4 degrees C) were observed in survivors and nonsurvivors. Posture, coat, and body weight were not accurate predictors of death. Only inability to ambulate, with a positive predictive value of 100% (11 of 11), accurately predicted death in the experimental mice of this study. CONCLUSION: Using this surrogate marker, loss of ability to ambulate, 11 of 13 mice that developed this sign could have been euthanized early, preventing anywhere from 2 to 22 h of potential distress prior to death. 相似文献
964.
Acute lanthanum chloride (250 mg/kg body wt) and neodymium chloride (200 mg/kg body wt) administrations resulted in significant enhancement of glutathione level in chick hepatic mitochondria. However, glutathione-s-transferase activity was depressed. There was no alteration in the activity of glutathione reductase. Activity of glucose-6-phosphate dehydrogenase was not altered under lanthanum and neodymium treatment. There was a significant enhancement of intramitochondrial glutathione peroxidase and superoxide dismutase. Lipid peroxidation remains the same as control group of animals. 相似文献
965.
Background
Detection of adaptive amino acid changes in proteins under recent short-term selection is of great interest for researchers studying microevolutionary processes in microbial pathogens or any other biological species. However, independent occurrence of such point mutations within genetically diverse haplotypes makes it difficult to detect the selection footprint by using traditional molecular evolutionary analyses. The recently developed Zonal Phylogeny (ZP) has been shown to be a useful analytic tool for identifying the footprints of short-term positive selection. ZP separates protein-encoding genes into evolutionarily long-term (with silent diversity) and short-term (without silent diversity) categories, or zones, followed by statistical analysis to detect signs of positive selection in the short-term zone. However, successful broad application of ZP for analysis of large haplotype datasets requires automation of the relatively labor-intensive computational process. 相似文献966.
The sinefungin producing, pock forming strain Streptomyces incarnatus was shown to be thiostrepton resistant. However, it does not produce thiostrepton and structurally related antibiotics. In this strain, five low copy plasmids of variable sizes were detected with electron microscopy. The strain S. lividans TK24 became thiostrepton resistant upon transformation by one of the plasmids of S. incarnatus. 相似文献
967.
968.
Asthma is a complex genetic disease, which arises from the interaction of multiple genes and environmental stimuli. These influences are important to asthma pathogenesis. These can be mechanically explained by the Epigenetic phenomenon, which consists of the chromatin and its modifications, as well as a covalent modification of cytosines residing at the dinucleotide sequence CG in DNA by methylation. This reaction is catalyzed by a family of DNA methyltransferase enzyme (DNMTs). DNMT1 is one of them which maintained the methylation status during replication and also critical for the development, differentiation and regulation of Th1 and Th2 cells. Therefore we studied the DNMT1 mRNA expression profiling as well as CpG methylation status in promoter region. For these studies we developed asthma mouse model, and used Flow cytometer, qRT2-PCR, Methylation specific PCR, bisulfate conversion and BiQ analyzer. We found that DNMT1 expression level was low in all the tissues (lung, trachea and BALF cells) of asthmatic in comparison to normal mice. This was due to the methylation of regulatory sites of DNMT1 promoter region at cytosine residue. As the incidence of asthma is increasing globally and in world, this study assumes greater significance in designing and developing therapeutic means. 相似文献
969.
970.
S Mukhopadhyay N Ghosh D Chattopadhyay S Mukhopadhyay D K Bhattacharya G C Chatterjee 《Indian journal of experimental biology》1989,27(1):69-71
Uptake of Cd by human RBC in vitro was studied. The uptake was found to be biphasic with a rapid initial phase followed by a slower second phase which was still increasing at the time of the last experiment (60 min). Both the phases were found to be independent of metabolically derived energy and unaffected by zinc in the incubation medium. 相似文献