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101.
The objective of this study was to determine theeffects of country liquor Toddy and its equivalentquantity of ethanol on lipid metabolism duringgestation in rats. Female rats weighing an average of125 g were exposed to Toddy (24.5 ml/body weight/day)and ethanol (0.52 ml/kg body weight/day) for 15 daysbefore conception and throughout gestation. On the19th day of gestation, altered liver function andhyperlipidemia was seen in both the treated groups.Altered liver function was evidenced by the increasedactivity of alcohol dehydrogenase, aldehydedehydrogenase, glutamic oxaloacetic transaminase oraspartate amino transferase (GOT), glutamic pyruvictransaminase or alanine amino transferase (GPT) andgamma glutamyl transpeptidase (GGT). Hyperlipidemiawas caused by increased biosynthesis and decreaseddegradation of lipids. The incorporation of 14Cacetate in lipids and activities of HMG CoA reductaseand lipogenic enzymes were elevated and activity ofLPL and bile acids contents were decreased. Toddytreated rats were more severely affected than thosereceiving an equivalent quantity of ethanol. Toddyseemed to potentiate the toxicity induced by alcoholindicating the role of the nonethanolic portion.Hepatic functions were also affected.  相似文献   
102.
103.
The efficacy of carbon fibres and plasma-preserved tendon allografts for gap repair in the superficial digital flexor tendon in the mid-metatarsal region was evaluated in 12 crossbred calves. Experimental tenectomies were performed, followed by implantation of carbon fibres in group I (12 legs) and plasma-preserved tendon allografts in group II (12 legs). Gross observations in group I showed filling of the defect with granulation tissue with more vascularity on day 7, which was less prominent at day 14. On day 30, the neotendon formed was slightly thicker and comparable to normal tendon in appearance and texture. On day 90, it exhibited all the characteristics of a fully developed tendon. Whereas, in group II increased vascularity at the site and encapsulation of the graft with connective tissue in early periods was observed. The gap between graft and host was filled with fibrous connective tissue. Peritendinous adhesions were maximum on day 7 which were gradually reduced in both groups. Microscopically, an acute inflammatory reaction in the periphery of carbon fibres was observed on day 7. Immature fibroblasts were arranged in a haphazard pattern at this stage. By day 14, numerous newly formed capillaries and comparatively more mature fibroblasts were present in between and around the carbon fibres which were aligning parallel to the longitudinal axis of the tendon. By day 30 the healing tissue exhibited longitudinal orientation of collagen fibres and was at a more advance stage of maturation. By day 90, the neotendon formed simulated the picture of normal tendon. In the grafted tendon group, there was normal healing tissue at the functional sites between host and grafted tendon. The fibroblastic activity appeared to be both extrinsic and intrinsic in origin. The connective tissue had invaded the graft to a variable distance and there was resorption of graft which was replaced by newly formed connective tissue on day 90. Scanning electron microscopic observation revealed formation of neotendon between carbon fibre strands, resulting in thickening of the implant. In later stages parallel collagen fibres resembling normal tendon were observed in both groups.  相似文献   
104.
The objective of this study was to determine the effects of an alcoholic beverage (Toddy) and the equivalent quantity of ethanol on carbohydrate metabolism in utero. Female rats were exposed to Toddy from coconut palm (24.5 ml/kg body weight/day) and ethanol (0.52 ml/kg body weight/day) for 15 days before conception and throughout gestation. On the 19th day of gestation, hypoglycemia was seen in both the treated groups, but it was more in the Toddy-treated group. Synthesis of glycogen was elevated on exposure to ethanol/Toddy but its degradation was enhanced only in alcohol-exposed rats. Key enzymes of citric acid cycle and gluconeogenesis were inhibited on administration of both alcohol and Toddy. Activity of glycolytic enzymes were increased. Toddy seemed to potentiate the toxicity induced by alcohol, indicating the additive effects of congeners.  相似文献   
105.
Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.  相似文献   
106.
Chickpea is sensitive to cold conditions (<15 °C), particularly at its reproductive phase and consequently it experiences significant decrease in the seed yield. The information about the effects of cold stress on chickpea during the seed filling phase is lacking. Moreover, the underlying metabolic reasons associated with the low temperature injury are largely unknown in the crop. Hence, the present study was undertaken with the objectives: (i) to find out the possible mechanisms leading to low temperature damage during the seed filling and (ii) to investigate the relative response of the microcarpa (Desi) and the macrocarpa (Kabuli) chickpea types along with elucidation of the possible mechanisms governing the differential cold sensitivity at this stage. At the time of initiation of the seed filling (pod size ∼1 cm), a set of plants growing under warm conditions of the glasshouse (temperature: 17/28 ± 2 °C as average night and day temperature) was subjected to cold conditions of the field (2.3/11.7 ± 2 °C as average night and day temperature), while another set was maintained under warm conditions (control). The chilling conditions resulted in the increase in electrolyte leakage, the loss of chlorophyll, the decrease in sucrose content and the reduction in water status in leaves, which occurred to a greater extent in the macrocarpa type than in the microcarpa type. The total plant weight decreased to the same level in both the chickpea types, whereas the rate and duration of the seed filling, seed size, seed weight, pods per plant and harvest index decreased greatly in the macrocarpa type. The stressed seeds of both the chickpea types experienced marked reduction in the accumulation of starch, proteins, fats, crude fibre, protein fractions (albumins, globulins, prolamins and glutelins) with a larger decrease in the macrocarpa type. The accumulation of sucrose and the activity levels of the enzymes like starch synthase, sucrose synthase and invertase decreased significantly in the seeds because of the chilling, indicating impairment in sucrose import. Minerals such as calcium, phosphorous and iron as well as several amino acids (phenylalanine, tyrosine, threonine, tryptophan, valine and histidine) were lowered significantly in the stressed seeds. These components were limited to a higher extent in the macrocarpa type indicating higher cold sensitivity of this type.  相似文献   
107.
Chickpea suffers cold stress (<10 °C) damage especially during reproductive phase resulting in the abortion of flowers and pods, poor pod set, and reduction in seed yield and seed quality. One of the ways in modifying cold tolerance involves exogenous treatment of the plants with chemicals having established role in cold tolerance. In the present study, the chickpea plants growing under optimum temperature conditions (28/12 °C, as average maximum and minimum temperature) were subjected to cold conditions of the field (10–12/2–4 °C; day/night as average maximum and minimum temperature) at the bud stage. Prior to exposure, these plants were treated exogenously with 10 μm abscisic acid (ABA) and thereafter again after 1 week of exposure. The stress injury measured in terms of increase in electrolyte leakage, decrease in 2,3,5-triphenyl tetrazolium chloride reduction %, relative leaf water content and chlorophyll content was observed to be significantly mitigated in ABA-applied plants. A greater pollen viability, pollen germination, flower retention and pod set were noticed in ABA-treated plants compared with stressed plants. The seed yield showed considerable improvement in the plants treated with ABA relative to the stressed plants that was attributed to the increase in seed weight, greater number of single seeded pods and reduction in number of infertile pods. The oxidative damage measured as thiobarbituric acid-reactive substances was lesser in ABA-treated plants that was associated with greater activities of superoxide dismutase, catalase, ascorbate peroxidase, ascorbic acid, glutathione and proline in these plants. It was concluded that cold stress effects were partly overcome by ABA treatment because of the improvement in water status of the leaves as well as the reduction in oxidative damage.  相似文献   
108.
109.
ABSTRACT

Bamboo scrimber is one of the most emerging structural materials for future building applications and it possesses properties comparable to other natural wood-based engineered materials such as glulam, laminated veneer lumber and cross-laminated timber. The goal of this work was to study the decay resistance of bamboo scrimber against white-rot (Trametes versicolor) and brown-rot fungi (Serpula lacrymans). Bamboo scrimber samples were incubated in petri dishes with the wood-decaying fungi and the weight loss after 12 weeks was measured. The surface morphology of fungal-degraded bamboo scrimber was evaluated using optical microscopy. Based on the percentage weight loss, bamboo scrimber could be classified as highly resistant against bio-deterioration by white and brown-rot fungi.  相似文献   
110.
Studies on reproductive biology are difficult but useful in species like Aegle marmelos (Linn.) Correa which is of considerable socio-economic importance and possess morphogenetic variation and qualities of wider adaptability to different soils. Cytology, phenology, pollination, breeding system and natural regeneration of wild and cultivated trees from India revealed the existence of diploid (2n = 18) and tetraploid trees (2n = 36) in Pachmarhi hills and only diploid trees in Punjab plains and Shiwalik hills. The diploid and tetraploid trees showed normal meiosis and high pollen fertility. Phenological events which included leaf fall, leaf emergence, floral bud break, flowering and fruiting are nearly the same in wild and cultivated trees. Natural pollen transfer in the species was highly efficient. Levels of fruit set following open pollination was quite high and is reduced considerably following hand pollination probably due to some injury caused to stigma during experiments. Inspite of synchronous nature of anther dehiscence and stigmatic receptivity, selfing in a flower was avoided due to herkogamy. Some selfing, however, occurred through geitonogamous mode as bagging of panicles yielded 12.21 ± 0.99 to 14.12 ± 0.91% fruit set. High pollen ovule ratio (9,250–10,600) indicated toward the obligate outbreeding nature. The species suited to insect and wind mode of pollination. High amount of air borne pollen grains deposited on glycerine smeared glass microscopic slides suggested towards the wind mode of pollination. Though flowers are dull coloured a variety of insects visited the flowers due to sweet fragrance and stamen/pollen as food reward. Among insect pollinators, honey bee (Apis dorsata) was the major and legitimate pollinator while the rest were either minor pollinators or mere visitors. Inspite of high fruit/seed set, natural regeneration through seeds was poor as fallen fruits were destroyed by fungal pathogens and white ants. The species also propagated vegetatively through coppices and root suckers. It lacks agamospermy as bagging of emasculated flowers yielded no fruit. It is inferred that ‘bael’ which lacks agamospermy reproduced successfully through gamospermy (xenogamy and geitonogamy) and vegetative mode (coppices and root suckers). We also concluded that tetraploid trees growing in the Pachmarhi hills with large sized fruits possessed better potentialities in horticulture if planted through root suckers or coppices.  相似文献   
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