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141.
Summary Wistar rats show a circadian variation in their response to stress. Pinealectomy exacerbates stress-induced gastric ulceration in rats. This effect is counteracted by melatonin administration.  相似文献   
142.
Summary The brain neurosecretory material is involved in the control of Corpora allata activity during post-embryonic development. A high concentration of neurosecretory material within the Corpora allata restrains the activity of the gland.  相似文献   
143.
Summary Removal of embryo axis before germination markedly prevents the development as well as subsequent decline in Flax cotyledon isocitritase. Cycloheximide inhibited the development and decline of the enzyme in intact cotyledons but prevented only the former in excised cotyledons.We thank Prof.W. Rahman, Head, Department of Chemistry for his interest and C.S.I.R. (India) for the award of Junior Research Fellowship to F.R.K.  相似文献   
144.
The different body fluid compartments in normally watered and 4-day water-deprived goats of Rajasthan desert, India, were measured in autumn. The goats maintained plasma volume and extracellular fluid volume, but lost gut and cell water considerably under the experimental conditions; indicating that the maintenance of the fluidity of the blood has priority over the body's other fluid requirements in this desert-adapted species during water deprivation.  相似文献   
145.
Summary The NCA 2 is dilated in about the middle of its length. Neurosecretory material is stored in this dilation. It serves as a secondary neurohaemal organ for lateral neurosecretion.  相似文献   
146.
Evidence for a modulation of the stress response by the pineal gland   总被引:2,自引:0,他引:2  
R Khan  S Daya  B Potgieter 《Experientia》1990,46(8):860-862
Wistar rats show a circadian variation in their response to stress. Pinealectomy exacerbates stress-induced gastric ulceration in rats. This effect is counteracted by melatonin administration.  相似文献   
147.
Résumé La persistance de la radioactivité incorporée dans le cholesterol et les lipides totaux de la myeline cérébrale a été mesurée pendant 200 jours après un injection i.p. de glucose U-14C chez des rats de 6 semaines ayant donc précisément dépassé la période de myelinisation active et également chez des animaux de 6 mois. La radioactivité spécifique relativement faible incorporée dans le cholesterol de la myeline des animaux les plus jeunes a décru lentement tandis que chez les animaux adultes elle est restée pratiquement constante. L'incorporation de carbone de glucose dans le cholesterol de la myeline des animaux adultes ne reflète probablement pas le «turnover» du cholesterol mais pourrait indiquer plutôt que la myeline continue à être formée lentement tout au long de la vie de l'animal.  相似文献   
148.
Zusammenfassung Die Zusammensetzung von in wässeriger Lösung gebildeten Ionenpaaren des Anions [W(CN)4(OH)4]4- mit Cr3+ bzw. Fe3+ wird amperometrisch ermittelt.

Acknowledgment. The authors are grateful to Dr.S. M. F. Rahman for providing necessary facilities and C.S.I.R. (India) for awarding a Junior Fellowship to one of them (K. U.).  相似文献   
149.
Atmospheric pressure MOCVD was used to deposit ZnO layers on sapphire and homoepitaxial template under different oxygen flow rates.Oxygen content affects the lattice constant value and texture coefficient of the films as evidenced by the θ-2θ peaks position and their intensity.Films deposited at lower oxygen flow rate possess higher value of strain and stresses.ZnO films deposited at high oxygen flow rates show intense UV emissions while samples prepared under oxygen deficient conditions exhibited defect related emission along with UV luminescence.The results are compared to the ZnO films deposited homoepitaxially on annealed ZnO samples.The data obtained suggest that ZnO stoichiometry is responsible for the structural and optical quality of ZnO films.  相似文献   
150.
Electromagnetic signals in deep reservoir are very weak so that it is difficult to predict about the presence of hydrocarbon in seabed logging(SBL) environment.In the present work,Mn0.8Zn0.2Fe2O4 nanoferrites were prepared by a sol–gel technique at different sintering temperatures of450 °C,650 °C and 850 °C to increase the strength of electromagnetic(EM) antenna.XRD,FESEM,Raman spectroscopy and HRTEM were used to analyze the phase,surface morphology and size of the nanoferrites.Magnetic properties of the nanoferrites were also measured using an impedance network analyzer.However,nanoferrites sintered at 850 °C with initial permeability of 200 and Q factor of 50 were used as magnetic feeders with the EM antenna.Lab scale experiments were performed to investigate the effect of magnetic field strength in scale tank.SPSS and MATLAB softwares were also used to confirm the oil presence in scale tank.It was observed that the magnitude of the EM waves for the antenna was increased up to 233%.Finally,the correlation values also show 208% increase in the magnetic field strength with the presence of the oil.Therefore,antenna with Mn0.8Zn0.2Fe2O4 nanoferrites based magnetic feeders can be used for deep water and deep target hydrocarbon exploration.  相似文献   
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