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Work induced stress led to decreased cholesterol and fluctuating triglyceride levels in gastrocnemius and pectoralis muscles in rats. But the drug (clenbuterol, 2 mg kg(-1) day(-1)) treatment increased cholesterol and triglyceride levels in both the muscles. However, heart showed decreased cholesterol and increased triglyceride level in the animals under work stress, but at the same time drug treatment led to a significant increase in levels of the two lipid fractions, inferring towards deleterious effect of the drug on heart.  相似文献   
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We examined a suitable swim program of different intensities and durations that could evoke changes in the myocardial antioxidant capacity in 22-month-old rats. Male rats (Rattus norvegicus) were assigned to either a sedentary control (SE-C) group or one of six trainee groups. Animals were swim-exercised for 4 weeks with either 20 min or 40 min/day, and three intensities, low, moderate and high. Low-intensity at 20 min/day elicited maximum swim velocity (Sv) and endurance capacity (P<0.05). While serum total cholesterol, triglyceride and low-density lipoprotein (LDL-C) levels were significantly reduced, high-density lipoprotein (HDL-C) showed an increase (P<0.05) in low-intensity trained rats (20 min/day) over SE-C. Notable reduction in blood lactate was also evident. Exercise training significantly increased superoxide dismutase (Mn-SOD), decreased lipid peroxidation products, malondialdehyde and lipofuscin in the left and right ventricles. Increased Mn-SOD with concomitant decrease in lipofuscin in left ventricle was significantly greater than in right ventricle. Moderate- to high-intensity exercise was not effective in either reducing lipid peroxidation products or elevating Mn-SOD activity. These data suggest that swim training at low-intensity of 20 min/day is beneficial as a major protective adaptation against oxidative stress in old myocardium.  相似文献   
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Thirty five bacterial isolates from diverse environmental sources such as contaminated food, nitrogen rich soil, activated sludges from pesticide and oil refineries effluent treatment plants were found to belong to Bacillus, Bordetella, Enterobacter, Proteus, and Pseudomonas sp. on the basis of 16S rRNA gene sequence analysis. Under dark fermentative conditions, maximum hydrogen (H2) yields (mol/mol of glucose added) were recorded to be 0.68 with Enterobacter aerogenes EGU16 followed by 0.63 with Bacillus cereus EGU43 and Bacillus thuringiensis EGU45. H2 constituted 63–69% of the total biogas evolved. Out of these 35 microbes, 18 isolates had the ability to produce polyhydroxybutyrate (PHB), which varied up to 500 mg/l of medium, equivalent to a yield of 66.6%. The highest PHB yield was recorded with B. cereus strain EGU3. Nine strains had high hydrolytic activities (zone of hydrolysis): lipase (34–38 mm) – Bacillus sphaericus strains EGU385, EGU399 and EGU542; protease (56–62 mm) – Bacillus sp. strains EGU444, EGU447 and EGU445; amylase (23 mm) – B. thuringiensis EGU378, marine bacterium strain EGU409 and Pseudomonas sp. strain EGU448. These strains with high hydrolytic activities had relatively low H2 producing abilities in the range of 0.26–0.42 mol/mol of glucose added and only B. thuringiensis strain EGU378 had the ability to produce PHB. This is the first report among the non-photosynthetic microbes, where the same organism(s) – B. cereus strain EGU43 and B. thuringiensis strain EGU45, have been shown to produce H2 – 0.63 mol/mol of glucose added and PHB – 420–435 mg/l medium.  相似文献   
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Summary Shoot regeneration in hairy root cultures of Solanum khasianum Clarke influences root growth, solasodine production. and permeabilization of solasodine into the medium. These parameters are dependent on exogenously supplied auxin and cytokinin: the effect being both concentration-and clone-dependent. Hairy root cultures with no shoot regeneration showed high permeabilization of solasodine into the medium by the sixth week of incubation, suggesting the medium acts as a sink for the solasodine synthesized by the roots. Solasodine in the culture medium was toxic to the transformed roots and caused browning of root tips. In a separate set of experiments, the hairy root cultures showed regeneration of approximately 50–70 mm long shoots after treatment with indole-3-acetic acid and kinetin. These hairy root cultures had inereased levels of solasodine production, compared to cultures without shoot regeneration. The plantlets formed in the hairy root cultures accumulated some of the solasodine, thereby reducing its permcabilization into the medium. Transport of solasodine from root to shoot reduced the toxic effect of solasodine in the root zone and extended the exponential growth phase by 8-10d.  相似文献   
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IntroductionPresent study was aimed to analyze the impact of education, employment and financial independence in breastfeeding practices among Indian women.MethodologyPresent explorative questionnaire based survey included 256 women (128 pairs) in the final analysis. A pair means – a) pregnant lady (in her third trimester) representing younger generation and b) her mother/mother in law representing the elder generation.ResultsWe found that the overall awareness regarding ‘breast milk’ being the best food for baby was excellent (overall 97.3%; younger generation: 96.9%; elder generation: 97.7%). Overall knowledge regarding the correct technique (28.9% younger generation and 21.9% elder generation) and frequency of breastfeeding (20.3% of younger generation and 34.4% of elder generation) was very poor. Less than 60% (younger generation: 57.8%; elder generation: 58.6%) were aware that the only major contraindication for breastfeeding is a mother infected with human immunodeficiency virus (HIV). On comparing responses obtained from the two generations of women, difference was not statistically significant among most of the issues related to breastfeeding. With regards to the attitude, despite better awareness, only 94.5% women in younger generation and 89.1% women in elder generation were planning to give mother’s milk as the first feed to the newborn. Similarly, less than 75% of women were ready to breast-feed the newborn immediately after birth. This was contradictory to the fact that 86% of pregnant women were aware that the baby should be breast-fed within an hour of birth.ConclusionAwareness with regards to breastfeeding issues had not changed significantly with the educational progress of Indian women. Despite the good level of awareness in the society regarding breastfeeding, attitude to practice the same is lacking.  相似文献   
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Among computationally predicted and experimentally validated plant miRNAs, several are conserved across species boundaries in the plant kingdom. In this study, a combined experimental–in silico approach was adopted for characterization of two conserved miRNAs, miR166 and miR171, from black pepper (Piper nigrum). A PCR-based detection and cloning strategy of miRNAs from tissues of black pepper was used. Conservation analysis of miR166 and miR171 along with their corresponding targets identified from P. nigrum revealed that these miRNAs are highly conserved with their counterparts in other plant species. miRNA-mediated cleavage of the conserved targets was also verified by RLM-RACE experiments. Real-time quantitative PCR revealed the differential expression patterns of these miRNAs in black pepper tissues. Our miRNA-based phylogenetic analysis of plants belonging to the Piperaceae family was in agreement with the typical paleoherb evolutionary scheme of primitive angiosperms. This method will help in the detection of evolutionarily conserved miRNAs in other plant species and provide a strategy for a novel phylogenetic reconstruction based on the evolutionary history of miRNA genes.  相似文献   
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