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951.
This study was undertaken to characterize the enzymatic properties of the particulate guanylyl cyclase previously shown to
be present at a high level of activity in purified rat brain myelin. Significant activation was achieved by both Lubrol-PX
and Triton X-100, the latters being somewhat more effective. A pH optimum of 7.8 was observed, compared to 7.4 for microsomes.
Employing 1.2 mM GTP with 1% Triton X-100, linearity of response was observed up to 60 min and approximately 1.2 mg of myelin
protein. Kinetic analysis revealed Km values of 0.258 mM and 0.486mM for myelin and microsomes, respectively, similar values being obtained by Lineweaver-Burke
analysis or Direct Linear Plot. Vmax values were 20 and 266 pmol/mg protein/min for myelin and microsomes, respectively. Washing of the myelin with 0.5 M NaCl
or 0.1% Na taurocholate did not remove a significant amount of guanylyl cyclase activity, indicating the enzyme to be intrinsic
to the myelin sheath.
Special issue dedicated to Dr. Marion E. Smith. 相似文献
952.
Ogelube, a small, shallow natural lake at Opi, a township near the University of Nigeria's Nsukka campus yielded 231 algal taxa. Most belonged to the Desmidiales, dominated by Cosmarium, and to the Chlorococcales dominated by Scenedesmus, giving 73 taxa new to West Africa. 相似文献
953.
954.
Activities of delta 5-3 beta- and 17 beta-hydroxysteroid dehydrogenase (delta 5-3 beta-HSD and 17 beta-HSD), Leydig cell nuclear area (LCNA) and spermatogenesis in the testis were observed after injection of lithium chloride in the 'antiserum to luteinizing hormone (LH)' treated toad. A significant decrease in the activities of steroidogenic enzymes, LCNA and spermatogenesis were noticed after the injections of 'antiserum to LH' to toads. Further decrease in the activities of the above parameters was observed in the lithium chloride--'antiserum to LH' treated toad. It is suggested that lithium chloride may inhibits testicular function without modulating the pituitary activity. 相似文献
955.
956.
Drug resistant malaria was a major factor contributing to the failure of a worldwide campaign to eradicate malaria in the last century, and now threatens the large investment being made by the global community in the rollout of effective new drug combinations to replace failed drugs. Four related papers in this issue of Malaria Journal make the case for creating the World Antimalarial Resistance Network (WARN), which will consist of four linked open-access global databases containing clinical, in vitro, molecular and pharmacological data, and networks of reference laboratories that will support these databases and related surveillance activities. WARN will serve as a public resource to guide antimalarial drug treatment and prevention policies and to help confirm and characterize the new emergence of new resistance to antimalarial drugs and to contain its spread. 相似文献
957.
Deboshikha Bhattacharjee Sanjoy Kumar Sheet Snehadrinarayan Khatua Koel Biswas Santaram Joshi Bekington Myrboh 《Bioorganic & medicinal chemistry》2018,26(18):5018-5028
A library of biologically important heterocycles, viz. pyrazolyl pyrimidine-triones, bis(heterocyclyl)methanes were successfully synthesised by the condensation of barbituric acid, pyrazolone with an aldehyde and dimedone/4-hydoxy coumarin with various substituted aldehydes in aqueous medium at room temperature catalysed by nickel nanoparticles which proved to be an efficient magnetically recyclable catalyst. The method is simple, eco-friendly and gave excellent yields of the products without taking recourse to column chromatographic separation procedures. Computational method was employed to elucidate the selective formation of uncyclised product in reaction course. The biological activity of the synthesized compounds were investigated and the results demonstrated profound antibacterial activity. 相似文献
958.
Due to staggered entries of patients during a clinical trial, the available exposure to observe the patients under a treatment is less and non-uniform while the patients with whom the trial is started initially are exposed to uniform exposures to the treatment. Because of this, the true response of the treatment gets masked. Here we have attempted to estimate the true response of the treatment in presence of staggered entries. Further, by Martingale approach the probability of acceptance/rejection has been worked out for both staggered and no staggered entry cases. The results are then compared with the help of a numerical example which shows that under staggered entries the treatment is rejected with higher probability. 相似文献
959.
Since the first discovery in the early 1990''s, the predicted and validated population of microRNAs (miRNAs or miRs) has grown
significantly. These small (~22 nucleotides long) regulators of gene expression have been implicated and associated with several
genes in the cancer pathway as well. Globally, the identification and verification of microRNAs as biomarkers for cancer cell types
has been the area of thrust for most miRNA biologists. However, there has been a noticeable vacuum when it comes to identifying
a common signature or trademark that could be used to demarcate a miR to be associated with the development or suppression of
cancer. To answer these queries, we report an in silico study involving the identification of global signatures in experimentally
validated microRNAs which have been associated with cancer. This study has thrown light on the presence of significant common
signatures, viz., - sequential and hybridization, which may distinguish a miR to be associated with cancer. Based on our analysis,
we suggest the utility of such signatures in the design and development of algorithms for prediction of miRs involved in the cancer
pathway. 相似文献
960.
Manosh Kumar Biswas Rafiul Islam Monzur Hossain 《Plant Cell, Tissue and Organ Culture》2007,90(1):49-54
Somatic embryogenesis was achieved from callus from leaf and nodal segments of strawberry clone pbgel-2000. The highest percent
of cultures with somatic embryos was achieved on MS medium supplemented with 1.0 mg/l 2,4-D, 0.5 mg/l BAP and 50% proline.
Darkness was the best condition for incubation with daily light periods over 6 h reducing the frequency of embryogenesis.
Regenerated plants (90–95%) were successfully transferred to soil, showed normal morphology and produced fruit four months
after planting. 相似文献