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711.
712.
A Husain W H Sawyer G J Howlett 《Biochemical and biophysical research communications》1983,111(2):360-365
The polymerization of actin in the presence of spectrin tetramers and band 4.1 isolated from the human erythrocyte has been measured using a fluorescence energy transfer technique. The results show that the cross-linking of spectrin-actin complexes by band 4.1 results in a limited depolymerization of actin filaments and a concomitant rise in the critical actin concentration. The phenomenon may explain in part the existence of actin in the erythrocyte cytoskeleton as short oligomers rather than as long filaments. 相似文献
713.
Using immunoblots and an affinity-purified antibody prepared against human erythrocyte protein 4.9, we have demonstrated and quantified the presence of an immunoreactive form of this protein in avian and bovine brain and lens tissues, avian heart, as well as in human platelets and mammalian, avian, piscine, and amphibian erythrocytes. Both the 48 kDa and the 52 kDa variants were observed in human erythrocytes, whereas 50 kDa and 54 kDa immunoreactive forms were observed in human platelets. As reported for erythroid protein 4.9, platelet protein 4.9 was phosphorylated in response to treatment with phorbol ester. Bovine brain showed five cross-reactive polypeptides in the 47 to 52 kDa range while avian brain and avian and bovine lens exhibited predominantly a 49-kDa band. Cross-reactivity was not observed in a number of cell lines and tissues including leukocytes, liver, kidney, pancreas, and skeletal muscle. Immunofluorescence indicated that protein 4.9 was present in cortical fiber cells of avian lens and in neurons of avian cerebrum. 相似文献
714.
Shano Shahanaj Islam Ariful Hagan Emily Rostal Melinda K. Martinez Stephanie Al Shakil Abdullah Hasan Moushumi Francisco Leilani Husain Mushtuq M. Rahman Mahmudur Flora Meerjady S. Miller Maureen Daszak Peter Epstein Jonathan H. 《EcoHealth》2021,18(4):487-499
EcoHealth - Anthropogenic land-use changes increase the frequency of interactions and habitat overlap between humans and macaques which play an important role in zoonotic disease transmission. This... 相似文献
715.
Syed Arif Kamal Khurs Eed A. Siddiqui S. A. Husain Muhammad Naeem N. U. Khan 《Journal of biological physics》1992,18(4):261-269
Effects of weak electromagnetic fields are considered on recently proposed covariant and generalized coupling models of global electrocortical activity. A method to calculate the ratio of components of signal velocities is given. First-order shift in frequencies is obtained in the presence of a weak, time-varying magnetic field. 相似文献
716.
717.
The synthetic amino acid, 3,4-dihydroxyphenylserine (DOPS) has been of great interest for many years as an adrenergic pro-drug, since the L-threo diastereomer of DOPS can be a precursor of R-(-)-norepinephrine, the natural form of this neurotransmitter. We now report bioactivation of DOPS to the potent pharmacological agent, noradrenalone (arterenone), via sequential stereoselective action by two target enzymes--dopamine beta-monooxygenase (DBM) and L-aromatic amino acid decarboxylase (AADC)--acting in tandem. Enzymatic activation is stereospecific, with only the L-erythro DOPS diastereomer producing noradrenalone; this is consistent with the known stereospecificities of AADC and DBM. These results provide a heretofore unrecognized rationale for the bioactivity of L-erythro DOPS and provide a basis for the design of new adrenergic pro-drugs. 相似文献
718.
Drechslera maydis causing severe leaf blight of Costus speciosus, produced toxic matabolites in vitro. Maximum toxin was produced in modified Fries’ medium if its carbon source was substituted with glucose and nitrogen source with asparagine. Highest toxin accumulation was found at 21 days of incubation and with the initial pH 5.0. The toxin was stable in acidic condition (pH 3.5—7.0) but unstable under alkaline conditions. 相似文献
719.
Pterocarpus marsupium (Bijasal) is a valuable multipurpose forest tree. The regeneration rate in natural habitat is low and the tree is overexploited.
An in vitro propagation protocol has been developed from nodal explants obtained from in vitro raised 18-day-old axenic seedlings.
The highest shoot regeneration frequency (85%), maximum number of multiple shoots (8.6) as well as length (4.8 cm) were induced
from nodal explants on Murashige and Skoog (MS) medium amended with 4.0 μM 6-benzyladenine (BA), 0.5 μM indole-3-acetic acid
(IAA) and 20 μM adenine sulphate (AdS). The percentage of shoot multiplication as well as the number of shoots per node remained
the same during the first two subculture, afterwards a decline was recorded. Rooting was best induced in microshoots excised
from proliferated shoot cultures on semisolid hormone-free half-strength MS medium, after a pulse (dip) treatment for 7 days
in half-strength MS liquid medium containing 100 μM indole-3-butyric acid (IBA) and 15.84 μM phloroglucinol (PG). The in vitro-raised
plantlets were potted and acclimatized under culture room conditions for 4 weeks before their transfer to a greenhouse, where
the established plants showed 75% survival. 相似文献
720.
A model for global electrocortical activity is developed by considering telencephalonic structures as mass of linked oscillators generating activity with a number of resonant modes. Equations for the signals are written in the comoving frame and then transformed into the laboratory frame. The state transition matrix is obtained in the presence of electric and magnetic fields. 相似文献