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91.
Oxygen uptake of Channa marulius was studied under water with and without access to air. There was a significant increase in the oxygen uptake through the gills when access to air was prevented. However, this value (0.863 ± 0.058 mlO2/indiv./h) was quite low in comparison to the total bimodal oxygen uptake (2.04 ± 0.14 mlO2/indiv./h) in juveniles. In adult fish the oxygen uptake per unit time increased appreciably (4.673 ± 0.404 mlO2/indiv./h). In juveniles as well as in adults the air breathing dominated over aquatic breathing. This fish showed a definite circadian rhythm in the bimodal oxygen uptake during different hours of the day.This work was performed in the Ichthyology Laboratory, P. G. Dept. of Zoology, Bhagalpur University, and was supported by a research grant from Bhagalpur University  相似文献   
92.
Reclassification of incompatibility group L (IncL) plasmids.   总被引:1,自引:0,他引:1  
H Richards  N Datta 《Plasmid》1979,2(2):293-295
Plasmids classified as IncL are shown to be incompatible with plasmids of IncM and we propose to reclassify them as IncM.  相似文献   
93.
The porphyrin photosensitizer, meso-Tetra (4-N-methylpyridyl) porphine tetraperchlorate binds to calf thymus DNA by intercalation and by external electrostatic association. This was concluded from the results of measruements involving Scatchard analysis, viscometry, thermal denaturation, and circular dichroism.  相似文献   
94.
A plasmid, derived from a naturally occurring strain of Proteus mirabilis, conferred resistance to cephalosporins, apparently mediated by a beta-lactamase indistinguishable from that determined by the chromosomal gene of Escherichia coli K-12. There was evidence for a recombination event between the wild-type plasmid and a defective F factor (Fsp) in the Escherichia coli K-12 culture in which it was stored.  相似文献   
95.
A simple apparatus was designed for simultaneous general anesthesia of a number of small laboratory animals with spontaneous respiration. Anesthesia is consistent over many hr. The apparatus consists of an oxygen tank and vaporizer, a glass distribution bottle, and a non-return circuit of separate inspiratory and expiratory valves for each animal. The equipment is inexpensive to construct and can be rapidly adjusted for exact control of gas flow and anesthetic depth.  相似文献   
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Salient sensory environments experienced by a parental generation can exert intergenerational influences on offspring. While these data provide an exciting new perspective on biological inheritance, questions remain about causes and consequences of intergenerational influences of salient sensory experience. We previously showed that exposing male mice to a salient olfactory experience, like olfactory fear conditioning, resulted in offspring demonstrating a sensitivity to the odor used to condition the paternal generation and possessing enhanced neuroanatomical representation for that odor. In this study, we first injected RNA extracted from sperm of male mice that underwent olfactory fear conditioning into naïve single‐cell zygotes and found that adults that developed from these embryos had increased sensitivity and enhanced neuroanatomical representation for the odor (Odor A) with which the paternal male had been conditioned. Next, we found that female, but not male offspring sired by males conditioned with Odor A show enhanced consolidation of a weak single‐trial Odor A + shock fear conditioning protocol. Our data provide evidence that RNA found in the paternal germline after exposure to salient sensory experiences can contribute to intergenerational influences of such experiences, and that such intergenerational influences confer an element of adaptation to the offspring. In so doing, our study of intergenerational influences of parental sensory experience adds to existing literature on intergenerational influences of parental exposures to stress and dietary manipulations and suggests that some causes (sperm RNA) and consequences (behavioral flexibility) of intergenerational influences of parental experiences may be conserved across a variety of parental experiences.  相似文献   
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Journal of Plant Biochemistry and Biotechnology - Light regulates numerous aspects of plant growth and development like seed germination, seedling de-etiolation, pigment accumulation, cotyledon...  相似文献   
100.
International Journal of Peptide Research and Therapeutics - The growth of pathogens across the globe is developing at a very fast rate, thus turning into a worldwide health problem. Since, current...  相似文献   
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