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1.
M. Srinivasa Rao M. Chellapandian M. R. V. Krishnan 《Bioprocess and biosystems engineering》1995,13(4):211-214
Urease was immobilized onto gelatin-poly (HEMA) copolymer by covalent linkage. Maximum amount of urease was immobilized onto the support at a pH of 8.5. The optimal pH of the immobilized urease was similar to that of free urease; the optimal temperature showed an increase of 10 °C over the free enzyme. The stability of the immobilized urease for a range of pH, temperature and shelf life was greater than the corresponding values for the free enzyme. The same result was obtained for k
m
also.Grateful acknowledgement is made to CSIR, Govt. of India for the research associateship conferred on Dr. M. Chellapandian which helped the progress of this piece of research investigation. 相似文献
2.
Baris Akdemir Balaji Krishnan Tunay Senturk David G. Benditt 《Indian pacing and electrophysiology journal》2015,15(2):103-109
Syncope is among the most frequent forms of transient loss of consciousness (TLOC), and is characterized by a relatively brief and self-limited loss of consciousness that by definition is triggered by transient cerebral hypoperfusion. Most often, syncope is caused by a temporary drop of systemic arterial pressure below that required to maintain cerebral function, but brief enough not to cause permanent structural brain injury. Currently, approximately one-third of syncope/collapse patients seen in the emergency department (ED) or urgent care clinic are admitted to hospital for evaluation. The primary objective of developing syncope/TLOC risk stratification schemes is to provide guidance regarding the immediate prognostic risk of syncope patients presenting to the ED or clinic; thereafter, based on that risk assessment physicians may be better equipped to determine which patients can be safely evaluated as outpatients, and which require hospital care. In general, the need for hospitalization is determined by several key issues: i) the patient''s immediate (usually considered 1 week to 1 month) mortality risk and risk for physical injury (e.g., falls risk), ii) the patient''s ability to care for him/herself, and iii) whether certain treatments inherently require in-hospital initiation (e.g., pacemaker implantation). However, at present no single risk assessment protocol appears to be satisfactory for universal application, and development of a consensus recommendation is an essential next step. 相似文献
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A new binding assay for membrane receptor systems has been developed employing an air-driven ultracentrifuge (Beckman Airfuge). The main advantages of this method for measurement of radioligand binding in aqueous medium are (i) the rapidity (30 s) in separating the bound from the unbound fraction, (ii) the small volume (100 μl) of assay medium which permits a relatively small excess of ligand over receptor to be employed, and (iii) the simplicity of manipulations which allows a high degree of replication. The variation in a triplicate set of assays is usually less than 0.5%. By virtue of maintaining equilibrium throughout the assay the present method is especially useful for ligands exhibiting rapid reversibility in binding. Binding of [3H]ouabain to several membrane (Na+, K+)-ATPases and binding of [3H]etorphine to the oplate receptor from brain membranes are discussed here. Also the inhibition of [3H]ouabain binding by Tris is discussed. 相似文献
4.
B P Gardner F Theocleous J W Watt K R Krishnan 《BMJ (Clinical research ed.)》1985,291(6509):1620-1622
The case histories of the 37 patients of the Mersey Regional Spinal Injuries Centre who were artificially ventilated between 1968 and 1984 were reviewed. The patients and caring relatives were interviewed separately to determine their views. Of 21 patients who were still alive, 18 said that they would wish to be temporarily ventilated again if the need arose, two were undecided, and one said that she would wish to be allowed to die. Sixteen caring relatives said that they were glad that the decision to ventilate had been taken. Those who were not glad were all young mothers. The outcome from any combination of factors that existed before injury could not be predicted except that most patients over age 59 fared badly. Patients with spinal cord damage should be artificially ventilated if required, provided that this can be carried out well and that total emotional, educational, and physical support can be provided and maintained. Whether or not scarce resources should be deployed in this manner requires discussion. 相似文献
5.
The parsimony and bootstrap branching pattern of major groups of land plants derived from relevant 5S rRNA sequence trees
have been discussed in the light of paleobotanical and morphological evidences. Although 5S rRNA sequence information is not
useful for dileneating angiosperm relationships, it does capture the earlier phase of land plant evolution. The consensus
branching pattern indicates an ancient split of bryophytes and vascular plants from the charophycean algal stem. Among the
bryophytes,Marchantia andLophocolea appear to be phylogenetically close and together withPlagiomnium form a monophyletic group.Lycopodium andPsilotum arose early in vascular land plant evolution, independent of fem-sphenopsid branch. Gymnosperms are polyphyletic; conifers,
Gnetales and cycads emerge in that order with ginkgo joiningCycas. Among the conifers,Metasequoia,Juniperus andTaxus emerge as a branch independent ofPinus which joins Gnetales.
The phylogeny derived from the available ss-RNA sequences shows that angiosperms are monophyletic with monocots and dicots
diverging from a common stem. The nucleotide replacements during angiosperm descent from the gymnosperm ancestor which presumably
arose around 370 my ago indicates that monocots and dicots diverged around 180 my ago, which is compatible with the reported
divergence estimate of around 200 my ago deduced from chloroplast DNA sequences.
Since deceased. 相似文献
6.
Ramya Krishnan Rahul Ravikumar Menon Naoto Tanaka Hans-Jürgen Busse Srinivasan Krishnamurthi Natarajan Rameshkumar 《PloS one》2016,11(3)
A novel yellow colony-forming bacterium, strain P3B162T was isolated from the pokkali rice rhizosphere from Kerala, India, as part of a project study aimed at isolating plant growth beneficial rhizobacteria from saline tolerant pokkali rice and functionally evaluate their abilities to promote plant growth under saline conditions. The novel strain P3B162T possesses plant growth beneficial traits such as positive growth on 1-aminocyclopropane-1-carboxylic acid (ACC), production of indole acetic acid (IAA) and siderophore. In addition, it also showed important phenotypic characters such as ability to form biofilm and utilization of various components of plant root exudates (sugars, amino acids and organic acids), clearly indicating its lifestyle as a plant rhizosphere associated bacterium. Taxonomically, the novel strain P3B162T was affiliated to the genus Arthrobacter based on the collective results of phenotypic, genotypic and chemotaxonomic analyses. Moreover, molecular analysis using 16S rRNA gene showed Arthrobacter globiformis NBRC 12137T, Arthrobacter pascens DSM 20545T and Arthrobacter liuii DSXY973T as the closely related phylogenetic neighbours, showing more than 98% 16S rRNA similarity values, whereas the recA gene analysis displayed Arthrobacter liuii JCM 19864T as the nearest neighbour with 94.7% sequence similarity and only 91.7% to Arthrobacter globiformis LMG 3813T and 88.7% to Arthrobacter pascens LMG 16255T. However, the DNA-DNA hybridization values between strain P3B162T, Arthrobacter globiformis LMG 3813T, Arthrobacter pascens LMG 16255T and Arthrobacter liuii JCM 19864T was below 50%. In addition, the novel strain P3B162T can be distinguished from its closely related type strains by several phenotypic characters such as colony pigment, tolerance to NaCl, motility, reduction of nitrate, hydrolysis of DNA, acid from sucrose, cell wall sugars and cell wall peptidoglycan structure. In conclusion, the combined results of this study support the classification of strain P3B162T as a novel Arthrobacter species and we propose Arthrobacter pokkalii sp.nov.as its name. The type strain is P3B162T (= KCTC 29498T = MTCC 12358T). 相似文献
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