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Tartaric acid is synthesized on light in the leaves ofTamarindus indica L. and is translocated to the flowers during flowering seasons. The translocation of this acid to fruits keeps peace with their growth rate. The decline of the tartaric acid content per unit fresh weight in mature fruits is not due to their utilization or conversion, but largely due to the setting up of the seeds which are devoid of any tartaric acid. Tartaric acid content in both the leaves and fruits show variation in different seasons, while malic acid does not show any change excepting a small increase in March.  相似文献   
715.
Bharat Rai 《Plant and Soil》1976,44(1):233-236
Summary This study reports that the primary fungal colonizers of decaying leaves, which were rarely recorded with the last fungal colonizers in the pattern of succession in later stage of decaying, were persistent in dead tissues in the form of dormant mycelia and were unable to sporulate due to competition with last colonizers for nutrition and space in substrates. The presence of such fungi in suppressed and dormant condition in the sustrate is confirmed by transference of washed bits of leaves onto nutrient media which allowed them to grow and sporulate freely.A part of Ph.D. thesis approved by the Banaras Hindu University, 1968.  相似文献   
716.
1. Parallel determinations of the oxygen consumption by skin slices with glucose or galactose as substrate and of the concentration of DNA of the skin of various ages of rats were carried out to study the metabolic changes of the skin with age. 2. Both the oxygen consumption and the DNA content of the skin decreased rapidly till the attainment of maturity; thereafter the rate of decrease in oxygen consumption was lower whereas the concentration of DNA was constant. The decrease in the oxygen consumption during the early developmental period is thus due to the loss of cells, but the decrease in the older rats may be due to a decline in the activity of the cells of the skin as a result of aging. 3. The uptake of glucose by the skin decreased with increasing age.  相似文献   
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The present investigation reports coupling of ?- and α-amino groups of lysine (LS) with mannose (m-LS) and sodium alginate (SA), respectively, to reduce its toxicity. Prepared conjugate, m-LS-co-SA, was characterized through infra-red spectroscopy and differential scanning calorimetry. Cell viability studies were undertaken to assess the safety profile of the prepared conjugate. Microspheres, based on the conjugate, were prepared using spray drying technique and studied for targeting of isoniazid to alveolar macrophages (AMs). Pharmacokinetic studies of the optimized formulation batch were performed in Charles Foster rats.Infra-red spectral data of the synthesized conjugate were in agreement to the presumptive sequence of the conjugation process. Dispersibility, thermal stability and safety of the conjugate were conducive to its biomedical application. Microspheres, formulated from the conjugate, were of uniform size and offered satisfactory drug loading efficiency and in vitro release characteristics. X-ray diffraction studies established that drug was entrapped within the microspheres rather than being adsorbed on to the surface. Pharmacokinetic studies revealed that the conjugate could be a potential vehicle towards both active targeting of isoniazid to AMs and controlling its release rate.  相似文献   
719.
Beta‐turns in beta‐hairpins have been implicated as important sites in protein folding. In particular, two residue β‐turns, the most abundant connecting elements in beta‐hairpins, have been a major target for engineering protein stability and folding. In this study, we attempted to investigate and update the structural and sequence properties of two residue turns in beta‐hairpins with a large data set. For this, 3977 beta‐turns were extracted from 2394 nonhomologous protein chains and analyzed. First, the distribution, dihedral angles and twists of two residue turn types were determined, and compared with previous data. The trend of turn type occurrence and most structural features of the turn types were similar to previous results, but for the first time Type II turns in beta‐hairpins were identified. Second, sequence motifs for the turn types were devised based on amino acid positional potentials of two‐residue turns, and their distributions were examined. From this study, we could identify code‐like sequence motifs for the two residue beta‐turn types. Finally, structural and sequence properties of beta‐strands in the beta‐hairpins were analyzed, which revealed that the beta‐strands showed no specific sequence and structural patterns for turn types. The analytical results in this study are expected to be a reference in the engineering or design of beta‐hairpin turn structures and sequences. Proteins 2014; 82:1721–1733. © 2014 Wiley Periodicals, Inc.  相似文献   
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