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561.
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
562.
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
563.
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
564.
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
565.
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
566.
Shanshan Li Jessica De La Cruz Steven Hutchens Somshuvra Mukhopadhyay Zachary K. Criss Rohit Aita Oscar Pellon-Cardenas Joseph Hur Patricia Soteropoulos Seema Husain Puneet Dhawan Lieve Verlinden Geert Carmeliet James C. Fleet Noah F. Shroyer Michael P. Verzi Sylvia Christakos 《Molecular and cellular biology》2021,41(1)
567.
Chin Fang Ngim Syed M. Tupur Husain Sharifah Syed Hassan Amreeta Dhanoa Siti Aisyah Abdul Ahmad Jeevitha Mariapun Wan Fadhilah Wan Ismail Nevein Philip Botross Henien Nowrozy Kamar Jahan Lian Yih Pong Hesham Elshahawi Robert D. Hontz Tyler Warkentein Norazim Mohd Yunos 《PLoS neglected tropical diseases》2021,15(5)
BackgroundDengue fever is the most common mosquito-borne infection worldwide where an expanding surveillance and characterization of this infection are needed to better inform the healthcare system. In this surveillance-based study, we explored the prevalence and distinguishing features of dengue fever amongst febrile patients in a large community-based health facility in southern peninsular Malaysia.MethodsOver six months in 2018, we recruited 368 adults who met the WHO 2009 criteria for probable dengue infection. They underwent the following blood tests: full blood count, dengue virus (DENV) rapid diagnostic test (RDT), ELISA (dengue IgM and IgG), nested RT-PCR for dengue, multiplex qRT-PCR for Zika, Chikungunya and dengue as well as PCR tests for Leptopspira spp., Japanese encephalitis and West Nile virus.ResultsLaboratory-confirmed dengue infections (defined by positive tests in NS1, IgM, high-titre IgG or nested RT-PCR) were found in 167 (45.4%) patients. Of these 167 dengue patients, only 104 (62.3%) were positive on rapid diagnostic testing. Dengue infection was significantly associated with the following features: family or neighbours with dengue in the past week (AOR: 3.59, 95% CI:2.14–6.00, p<0.001), cutaneous rash (AOR: 3.58, 95% CI:1.77–7.23, p<0.001), increased temperature (AOR: 1.33, 95% CI:1.04–1.70, p = 0.021), leucopenia (white cell count < 4,000/μL) (AOR: 3.44, 95% CI:1.72–6.89, p<0.001) and thrombocytopenia (platelet count <150,000/μL)(AOR: 4.63, 95% CI:2.33–9.21, p<0.001). Dengue infection was negatively associated with runny nose (AOR: 0.47, 95% CI:0.29–0.78, p = 0.003) and arthralgia (AOR: 0.42, 95% CI:0.24–0.75, p = 0.004). Serotyping by nested RT-PCR revealed mostly mono-infections with DENV-2 (n = 64), DENV-1 (n = 32) and DENV-3 (n = 17); 14 co-infections occurred with DENV-1/DENV-2 (n = 13) and DENV-1/DENV-4 (n = 1). Besides dengue, none of the pathogens above were found in patients’ serum.ConclusionsAcute undifferentiated febrile infections are a diagnostic challenge for community-based clinicians. Rapid diagnostic tests are increasingly used to diagnose dengue infection but negative tests should be interpreted with caution as they fail to detect a considerable proportion of dengue infection. Certain clinical features and haematological parameters are important in the clinical diagnosis of dengue infection. 相似文献
568.
The paper deals with some important medicinal plants used in human skin diseases in Uttar Pradesh, India. Fifty species of 47 genera belonging to 30 families of pteridophytes and angiosperms are reported along with dosage rate and mode of administration. 相似文献