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71.
The current advances in fluorescence microscopy, coupled with the development of new fluorescent probes, make fluorescence resonance energy transfer (FRET) a powerful technique for studying molecular interactions inside living cells with improved spatial (angstrom) and temporal (nanosecond) resolution, distance range, and sensitivity and a broader range of biological applications.  相似文献   
72.
V Sekar  B C Carlton 《Gene》1985,33(2):151-158
A transformant of Bacillus megaterium, VB131, was isolated which carries a 6.3-kb XbaI segment of the crystal toxin gene of Bacillus thuringiensis var. israelensis (BTI) cloned in a vector plasmid pBC16 to yield pVB131. The chimeric plasmid DNA from VB131 was introduced into a transformable Bacillus subtilis strain by competence transformation. Both the B. megaterium VB131 strain and the B. subtilis strain harboring the chimeric plasmid produced irregular, parasporal, phase-refractile, crystalline inclusions (Cry+) during sporulation. The sporulated cells as well as the isolated crystal inclusions of the pVB131-containing B. megaterium and B. subtilis strains were highly toxic to the larvae of Aedes aegypti. Also, the solubilized crystal protein preparation from VB131[pVB131] showed clear immuno cross-reaction with antiserum to the BTI crystal toxin. 32P-labeled pVB131 plasmid DNA showed specific hybridization with a 112-kb plasmid DNA of Cry+ strains of BTI, and no hybridization with other plasmid or chromosomal DNA of either Cry+ or Cry- variants. These results are in agreement with our previous findings (González and Carlton, 1984) that the 112-kb plasmid of BTI is associated with the production of the crystal toxin.  相似文献   
73.
The highest values of consanguinity was found among “Kamma” (45.0%), “Ediga” (47.5%) and “Mala” (55.7%) who occupy different strata of Indian caste hierarchy. In the way of searchout the factors influencing consanguineous marriages, the present paper finda the negative relationship between educational levels of the spouses and consanguinity. The educational levels of men has significant effect on the frequency of consanguinious marriages among “Kamma” and “Mala”. However, further analysis deplore significant differences in the mean levels consanguinity between educational groups. It divulge low level of higher education among the populations. Only 12% of men and 1.6% of women have degree level and above education in the total sample.  相似文献   
74.
Computational genomic analysis of hemorrhagic fever viruses   总被引:6,自引:0,他引:6  
A number of distinct viruses are known as hemorrhagic fever viruses based on a shared ability to induce hemorrhage by poorly understood mechanisms, typically involving the formation of blood clots (“disseminated intravascular coagulation”). It is well documented that selenium plays a significant role in the regulation of blood clotting via its effects on the thromboxane/prostacyclin ratio, and effects on the complement system. Selenium has an anticlotting effect, whereas selenium deficiency has a proclotting or thrombotic effect. It is also well documented that extreme dietary selenium deficiency, which is almost never seen in humans, has been associated with hemorrhagic effects in animals. Thus, the possibility that viral selenoprotein synthesis might contribute to hemorrhagic symptoms merits further consideration. Computational genomic analysis of certain hemorrhagic fever viruses reveals the presence of potential protein coding regions (PPCRs) containing large numbers of in-frame UGA codons, particularly in the −1 reading frame. In some cases, these clusterings of UGA codons are very unlikely to have arisen by chance, suggesting that these UGAs may have some function other than being a stop codon, such as encoding selenocysteine. For this to be possible, a downstream selenocysteine insertion element (SECIS) is required. Ebola Zaire, the most notorious hemorrhagic fever virus, has a PPCR with 17 UGA codons, and several potential SECIS elements can be identified in the viral genome. One potential viral selenoprotein may contain up to 16 selenium atoms per molecule. Biosynthesis of this protein could impose an unprecedented selenium demand on the host, potentially leading to severe lipid peroxidation and cell membrane destruction, and contributing to hemorrhagic symptoms. Alternatively, even in the absence of programmed selenoprotein synthesis, it is possible that random slippage errors would lead to increased encounters with UGA codons in overlapping reading frames, and thus potentially to nonspecific depletion of SeC in the host.  相似文献   
75.
Smoking problem is considered as one of the hot topics for many years. In spite of overpowering facts about the dangers, smoking is still a bad habit widely spread and socially accepted. Many people start smoking during their gymnasium period. The discovery of the dangers of smoking gave a warning sign of danger for individuals. There are different statistical methods used to analyze the dangers of smoking. In this study, we apply an algebraic statistical method to analyze and classify real data using Markov basis for the independent model on the contingency table. Results show that the Markov basis based classification is able to distinguish different date elements. Moreover, we check our proposed method via information theory by utilizing the Shannon formula to illustrate which one of these alternative tables is the best in term of independent.  相似文献   
76.
77.
Abstract— The isolation of brain actomyosin-like protein (neurostenin) with a Ca2+ -sensitive component is described. The addition of 1 m m EGTA results in approximately 50 per cent reduction in MgATPase activity. The inhibition can be released by a free Ca2+ concentration of 10−6 m . Dialysis of the protein complex against low ionic strength medium followed by centrifugation results in a loss of Ca2+ sensitivity in the pelleted protein. Ca2+ sensitivity can be restored by reprecipitating this desensitized complex in the presence of the 70.000 g supernatant. The protection of sulphhydryl groups during desensitization and reconstitution procedures is essential. This Ca2+ regulatory property is similar, in these respects, to other actomyosin-like proteins.  相似文献   
78.
M C Sekar  B D Roufogalis 《Life sciences》1984,35(14):1527-1533
The effects of muscarinic and alpha-adrenergic receptor stimulation on phosphoinositide turnover in rat atria have been compared. Despite the similar densities of muscarinic receptors in rat left and right atria, 0.1 mM carbachol increased [32P]phosphate incorporation into phosphatidylinositol (PI) by 35% (p less than 0.05) in left atria but had no effect in right atria. By contrast to the small muscarinic receptor effect, stimulation of alpha 1-adrenergic receptors by 0.1 mM methoxamine produced a more than two fold increase in [32P]phosphate incorporation into PI in both left and right atria, despite the reported smaller density of alpha-adrenergic receptors in rat atria compared to muscarinic receptors. Enhanced phosphate labelling by methoxamine did not occur in phospholipids other than PI, and was blocked by the alpha-adrenergic antagonist, phentolamine (20 microM). The results indicate that the majority of the muscarinic receptors in rat atria are not coupled to phosphoinositide turnover. If indeed the observed enhancement in [32P]-phosphate labelling by carbachol reflects phosphoinositide turnover, and assuming equal coupling efficiencies of muscarinic and adrenergic receptors, it is calculated that not more than 2% of the muscarinic receptors in rat left atria are coupled to this response.  相似文献   
79.
Distant repeats in protein sequence play an important role in various aspects of protein analysis. A keen analysis of the distant repeats would enable to establish a firm relation of the repeats with respect to their function and three-dimensional structure during the evolutionary process. Further, it enlightens the diversity of duplication during the evolution. To this end, an algorithm has been developed to find all distant repeats in a protein sequence. The scores from Point Accepted Mutation (PAM) matrix has been deployed for the identification of amino acid substitutions while detecting the distant repeats. Due to the biological importance of distant repeats, the proposed algorithm will be of importance to structural biologists, molecular biologists, biochemists and researchers involved in phylogenetic and evolutionary studies.  相似文献   
80.

Trees are acknowledged as most valued gift of nature and saviour of earth, enhancing and protecting landscapes, ecosystems and production systems. An authentic database of tree flora missing from local to global scale has immense value. Formulation of conservation and management policies are difficult owing to huge variation in number of species, lack of tree cover and quantification of tree diversity. To endow with a pragmatic groundwork for quantification of tree diversity of IHR, we had published an inventory of 1466 tree species (Angiosperms and Gymnosperms) along with their taxonomically vetted scientific name, distributional range, phenological attributes (leaf persistence and flower colour), use value, congruence, endemism and threatened species. One more database on tree diversity of Western Himalaya was also published with an annotated list of tree flora compiled from unrestricted literature and e-floras related to the regions. The present paper is an attempt to bring out the overall representation of tree flora of IHR, its distributional pattern, congruence, and endemism criterion in Western and Eastern Himalaya along with correlation between the regions as well as states.

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