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41.
M. Misra 《Biologia Plantarum》1995,37(2):219-223
Patchouli (Pogostemon cablin Benth.) plants grown under shade (LI) showed an increased height due to internodal elongation, leaf area, leaf area index, and chlorophyll (Chl)b, Chl (a+b) and carotenoid (Car) contents compared to the plants grown in sunlight (HI). The number of branches and green leaves decreased under LI treatment, with a marginal variation in the patchouli oil yield. A comparison between the relative contents of photosynthetic pigments indicated that Chlb and Car accumuled preferentially over Chla in the LI grown plants. 相似文献
42.
Summary Glutamate (Glu) the major amino acid in mammalian brain and most dietary proteins possesses neurotransmitter as well as neurotoxic properties. We administered monosodium glutamate (MSG) 4 mg/g bwt, sc on postnatal day (PND) 1 through 10 to rats on alternate days or daily and sacrificed them on PND 45 or PND 90 respectively. The activities of glutamate dehydrogenase and aminotransferases were evaluated in the circumventricular organs of brain. Results show that neonatal MSG produces alterations in glutamate metabolism in blood-brain-barrier deficient regions. 相似文献
43.
Prakash C. Misra Theodore A. Craig Frederick L. Crane 《Journal of bioenergetics and biomembranes》1984,16(2):143-152
Carrot (Daucus carota L.) cells grown in suspension culture oxidized exogeneous NADH. The NADH oxidation was able to stimulate K+ (86Rb+) transport into cells, but it did not affect sucrose transport.N,N'-Dicyclohexyl-carbodiimide, diethylstilbestrol, and oligomycin, which only partially inhibited NADH oxidation, almost completely collapsed the K+ (86Rb+) transport. Vanadate, which is less effective as an ion transport inhibitor, was less effective in inhibiting the NADH-driven transport of K+ (86Rb+).p-Fluormethoxycarbonylcyanide phenylhydrazone inhibits the K+ transport over 90% including that induced by NADH. The results are interpreted as evidence that a plasma membrane redox system in root cells is closely associated with the ATPase which can drive K+ transport. Because of the inhibitor effects, it appears that membrane components common to the redox system and ATPase function in the transport of K+. 相似文献
44.
This paper is an analytical study on the pulse wave velocities in the aorta. In conformity to a physiologic state of loading,
the distensibility of the vessel wall has been accounted for. The wall material is treated by using the theory of large elastic
deformations. The orthotropicity of wall tissues and the effect of the surrounding tissues have been incorporated in the analysis
which is based on the use of the strain energy function suggested by Vaishnavet al. Numerical values of the wave velocities of the canine middle descending thoracic aorta are computed by using the derived
analytical expressions. 相似文献
45.
All four isolates of Yersinia enterocolitica and one isolate of Y. frederiksenii from pigs were found to be enterotoxigenic. Whole-cell preparations of Y. enterocolitica isolates did not induce any change in the rabbit ligated gut test after 6 and 18 h of inoculation, but Y. frederiksenii on the other hand showed a positive gut response at 18 h. Cell-free supernatant (CFS) of all five isolates induced dilatation in the rabbit gut up to 6 h, after which Y. enterocolitica became negative, while Y. frederiksenii continued to show a reaction up to 18 h. CFS of all five isolates were also found positive with the infant mouse test. Of the five isolates of Yersinia, three gave a positive reaction for the permeability factor on rabbit skin. Yersinia enterotoxin could be concentrated by methanol extraction. It was stable at 100°C for 20 min and at 120°C for 15 min. However, its activity was lost at low (2.0) and high pH (10.0). Enterotoxic preparations of Y. enterocolitica lost part of their enterotoxic activity upon dialysis. 相似文献
46.
Summary The concentration, uptake and element use efficiency of N, P and K in one C3 annual (Polypogon monspeliensis) and two C4 (Echinochloa colonum, an annual, andDichathium annulatum, a perennial) grasses were determined during winter and summer seasons in monocultures raised in field plots at three moisture
levels,viz. full, half and one-fourth of field capacity. At each moisture regime the plants were clipped thrice at moderate and severe
levels corresponding to 40 and 80% of live green. The concentration of these elements was characteristic of the growth habit
of these plants;e.g. the build up of concentration was maximum in leaf of the annuals while it was comparable in crown and leaf of Dichanthium.
The N level was maximum in Polypogon. The nutrient use effiency was comparable in the two annuals and maximum K and N use
were obtained in Polypogon and Dichanthium, respectively. 相似文献
47.
Summary Phytohormones like IAA and kinetin inhibit chlorophyll loss during aging of wheat chloroplasts duringin vivo andin vitro. GA, on the other hand, stimulates the pigment degradation during aging of attached leaves in contrast to its senescence inhibiting action in detached leaves and isolated chloroplasts. A shift in optimum concentration of hormone in inhibiting chlorophyll degradation suggests a differential pool size of endogenous hormone regulating aging of chloroplastsin vivo andin vitro. The retardation of chlorophyll loss by kinetin, IAA and GA during aging of chloroplastsin vitro would indicate that the effect of hormones in preventing yellowing of senescing leaves may be mediated through their direct action on chloroplasts. 相似文献
48.
On adsorption of some electron-acceptor molecules on the solid films of all-trans-beta-carotene, beta-apo-8'-carotenal, astacene and methylbixin a new absorption band appears on the longer-wavelength side of the spectrum in addition to the original bands. The position of this new band is dependent on the electron affinity (EA) of the acceptor molecules, and the intensity of this band increases with the amount of adsorbed acceptor molecules. A linear relationship between the vmax. of the new band and EA was observed. The value of the ionization potential of the polyenes estimated from such linear relationship agrees satisfactorily with the value obtained by other methods. It has been concluded that the polyenes behave as electron donor and first form molecular charge-transfer complexes (of type [polyene . I2] with iodine) with electron acceptors, these finally dissociating to yield ionic complexes (of type [polyene . I+] with iodine). 相似文献
49.
Superoxide dismutase: a photochemical augmentation assay. 总被引:21,自引:0,他引:21
Cell envelope vesicles containing bacteriorhodopsin, prepared from Halobacterium halobium, have previously been shown to accumulate glutamate to high concentration gradients when illuminated. This active transport is energized by a sodium gradient (Naout+ ? Nain+), which arises from Na+-efflux coupled to the light-induced H+-gradient. The oxidation of dimethyl phenylenediamine (DPD) by the vesicles also can drive uphill glutamate transport, and such transport is inhibited by KCN, azide, ionophores, or uncouplers. KT for glutamate is 1.4 × 10?7m under these conditions, as compared to 1.3 × 10?7m for light-induced transport. The respiration-induced transport of glutamate is dependent on high Na+ concentrations on the vesicle exterior and requires low Na+ concentrations in the interior. When Na+ of increasing concentrations is included in the vesicles, transport proceeds with increasing lags, similarly to the case of light-driven transport. In vesicles to which DPD is added first, and then KCN at increasing time intervals (5 to 15 min), glutamate transport occurs after the addition of KCN, with increasing rates, even though respiration is inhibited. This indicates that the energy generated by DPD-oxidation is conserved over several minutes. These results suggest that in the case of respiration-dependent glutamate transport the translocation is also driven by a Na+-gradient; thus, there is a single glutamate transport system independent of the source of energy. The generation of such an Na+-gradient during DPD-oxidation implies that the respiration component involved, cytochrome oxidase, is functionally equivalent to bacteriorhodopsin, which acts as a proton pump. 相似文献
50.
Vijai P. Misra 《Carbohydrate research》1977,59(1):35-46
The effect of various added electrolytes (sodium and potassium halides of progressively increasing molecular volume) on the viscosity behavior of aqueous sucrose solution (292mM) has been investigated. Data are presented for the concentration range 0.125–3M of the electrolytes over the temperature range of 25 to 40°. The data have been found to satisfy Moulik's equation,(η/η0)2M +K1C2, for concentrated solutions of electrolytes beyond the Einstein region. The “effective” rigid, molar volume (Ve) and apparent. Jones-Dole B-coefficient (in sucrose solution) have been computed by employing the Breslau-Miller treatment. The change in the viscosity behavior is attributed to structuring effects in solution. 相似文献