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31.
Studies on the incorporation of DL-[1- 14-C] leucine into myosin, total myofibrillar protein and total sarcoplasmic protein have shown age-dependent alterations in the rate of synthesis of these protiens in red and white skeletal muscles of chicks. During the early phase of ex ovo development white muscle synthesizes significantly higher amounts of myofibrillar proteins, especially myosin, in comparison with red muscle. The rate of sarcoplasmic protein synthesis in red and white muscles one day after hatching is almost identical. The red muscle shows a markedly higher rate of sarcoplasmic protein synthesis from 10 days after hatching. The incorporation of amino acid into various protein fractions of both the muscle types decreases with advancing age. In adult chicks red muscle displays a higher ability to synthesize sarcoplasmic and myofibrillar proteins.  相似文献   
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Incorporation of [14C]leucine into proteins of 3rd instar Culex pipiens quinquefasciatus Say larvae increases linearly with time between 1 and 4 h. Garlic oil as well as the active larvacidal principle from it, viz. diallyl disulphide, inhibits significantly synthesis of the larval proteins. The maximum reduction in incorporation is observed during the first hour of treatment. The incorporation of [14C]phenylalanine is also inhibited by garlic oil and the effect is irreversible. Garlic oil does not seem to have any effect on proteins already labelled and it does not suppress substantially oxygen uptake by the larvae.  相似文献   
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Aim:  To isolate and identify black pepper ( Piper nigrum L) associated endophytic bacteria antagonistic to Phytophthora capsici causing foot rot disease.
Methods and Results:  Endophytic bacteria (74) were isolated, characterized and evaluated against P. capsici . Six genera belong to Pseudomonas spp (20 strains), Serratia (1 strain), Bacillus spp. (22 strains), Arthrobacter spp. (15 strains), Micrococcus spp. (7 strains), Curtobacterium sp. (1 strain) and eight unidentified strains were isolated from internal tissues of root and stem. Three isolates, IISRBP 35, IISRBP 25 and IISRBP 17 were found effective for Phytophthora suppression in multilevel screening assays which recorded over 70% disease suppression in green house trials. A species closest match (99% similarity) of IISRBP 35 was established as Pseudomonas aeruginosa ( Pseudomonas EF568931), IISRBP 25 as P. putida ( Pseudomonas EF568932), and IISRBP 17 as Bacillus megaterium ( B. megaterium EU071712) based on 16S rDNA sequencing.
Conclusion:  Black pepper associated P. aeruginosa , P. putida and B. megaterium were identified as effective antagonistic endophytes for biological control of Phytophthora foot rot in black pepper.
Significance and Impact of the Study:  This work provides the first evidence for endophytic bacterial diversity in black pepper stem and roots, with biocontrol potential against P. capsici infection.  相似文献   
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In the first decade of this new millennium, health professionals are faced with a rapidly increasing need for child mental health services and changing models of service provision. This gives us a unique opportunity to make provision for services where it has not been available before, or to improve upon the existing services. This paper examines the challenges and opportunities while attempting to integrate child mental health services to primary care.  相似文献   
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Lateral exchange of water and nutrients between xylem and surrounding tissues helps to de‐couple uptake from utilization in all parts of a plant. We studied the dynamics of these exchanges, using stable isotope tracers for water (H218O), magnesium (26Mg), potassium (41K) and calcium (44Ca) delivered via a cut stem for various periods to the transpiration stream of bean shoots (Phaseolus vulgaris cv. Fardenlosa Shiny). Tracers were subsequently mapped in stem cross‐sections with cryo‐secondary ion mass spectrometry. The water tracer equilibrated within minutes across the entire cross‐section. In contrast, the nutrient tracers showed a very heterogeneous exchange between xylem vessels and the different stem tissues, even after 4 h. Dynamics of nutrients in the tissues revealed a fast and extensive exchange of nutrients in the xylem parenchyma, with, for example, calcium being completely replaced by tracer in less than 5 min. Dilution of potassium tracer during its 30 s transit in xylem sap through the stem showed that potassium concentration was up‐regulated over many hours, to the extent that some of it was probably supplied by phloem recirculation from the shoot.  相似文献   
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Nitric oxide (NO) is known to possess antiparasitic activity towards Plasmodium species. Parasite proteases are currently considered to be promising targets for antimalarial chemotherapy. In the present study, we have studied the inhibitory effect of NO on the activity of plasmepsin in Plasmodium vivax, the pepsin-like aspartic protease which is believed to be involved in the cleavage during hemoglobin degradation in Plasmodium falciparum. NO donors (+/-) (E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR-3), S-nitrosoglutathione (GSNO), and sodium nitroprusside (SNP) were found to inhibit this plasmepsin activity in a dose-dependent manner in purified P. vivax aspartic protease enzyme extracts. This inhibitory effect may be attributable to the nitrosylation of the cysteine residue at the catalytic site. However, an inhibitor of aspartic protease activity, namely pepstatin, was also found to inhibit (IC50 3 microM ) the enzyme activity, which we have used as a positive control. Our results therefore provide novel insights into the pathophysiological mechanisms, and will be useful for designing strategies for selectively upregulating NO production in P. vivax infections for antimalarial chemotherapy and also biochemical adaptations of the malaria parasite for survival in the host erythrocytes with a better understanding of the protease substrate interactions.  相似文献   
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