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11.
Two new compounds G and H isolated from the roots of Costus speciosus have been characterized as 8-hydroxytriacontan-25-one and Me tritriacontanoat 相似文献
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Summary A series of factoral experiments involving the effects of gravel concentration in the subsoil horizon, the effect of inter-gravel
bulk density, the depth of the surface soil above the gravel horizon and the interaction between soil moisture regime and
gravel concentration, on growth and development of maize roots were conducted in the greenhouse. Increasing sub soil gravel
concentration decreased the total porosity and the available waterholding capacity. Though the root growth of maize seedlings
was adversely affected by gravel concentration above 20 per cent, lower concentration of gravels had a beneficial effect on
roots. The root development and the leaf concentration of N, P and K improved with increasing depth of surface soil above
the gravel horizon. The symptoms of mechanical impedance, such as thickening of root tips and profuse branching behind the
tip were commonly observed on the root axis penetrating the gravelly horizon. re]19750916 相似文献
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Rats withdrawn from continuous morphine infusion showed reliable occurrence of withdrawal body shakes. This sign of narcotic withdrawal was inhibited by the neuroleptic drug, (+) butaclamol. (?) Butaclamol was inactive. (+) Butaclamol activity was not antagonized by naloxone (5 mg/kg). The anti-withdrawal mechanism of (+) butaclamol is discussed in terms of effects on dopamine and narcotic receptors.The butyrophenone neuroleptic, haloperidol, has been used successfully to reduce signs of narcotic withdrawal in laboratory animals (1–4) and human addicts (5). Other neuroleptics of the butyrophenone type also show anti-withdrawal action (6, 7). The mechanism of action of these neuroleptics in blocking narcotic withdrawal is not understood. Butaclamol is a new neuroleptic drug that is available in two enantiomers and only (+) butaclamol possesses neuroleptic activity (8–10). Because of its demonstrated stereo-specificity in producing its pharmacological action, we employed this drug to establish specificity of action of neuroleptics in blocking narcotic withdrawal. 相似文献
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Stage-specific ribosomal RNA expression switches during sporozoite invasion of hepatocytes 总被引:2,自引:0,他引:2
J D Zhu A P Waters A Appiah T F McCutchan A A Lal M R Hollingdale 《The Journal of biological chemistry》1990,265(21):12740-12744
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Pradhan Satyabrata Singh Sanjay Kumar Srivastav Manish Prakash Jai Lal Sanjay Kumar Padaria Jasdeep Chatrath Goswami Amit Kumar Maurya Naveen Kumar 《Plant Cell, Tissue and Organ Culture》2021,145(1):155-172
Plant Cell, Tissue and Organ Culture (PCTOC) - A method for in vitro screening and selection of drought (moisture stress) tolerant mango calli was developed. Poly ethylene glycol (PEG) (Molecular... 相似文献
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In the present investigation, daily variations in plasma levels of melatonin, testosterone and estradiol-17β were analysed in the tropical freshwater catfish, Clarias batrachus during early and late-preparatory, pre-spawning, late-spawning and post-spawning phases of its annual reproductive cycle. Plasma melatonin levels exhibited a significant circadian rhythm during all the reproductive phases but peaks were invariably at night. The amplitude of melatonin was high during the early-preparatory phase and low in the pre-spawning phase. Testosterone also displayed significant rhythm during all the studied phases except post spawning phase. Estradiol-17β revealed diurnal rhythm only during preparatory and pre-spawning phases. The peak in the levels of plasma testosterone and estradiol-17β were recorded during the photophase. During the late-preparatory phase, the rhythm of testosterone coincided with the rhythm of estradiol-17β. 相似文献