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1.
A preliminary survey of the few units of the small-scale glass bangle industry in Firozabad, Agra District, Uttar Pradesh, indicated that the workers were exposed to severe degrees of heat stress during various operations in the manufacturing processes. A more detailed study in eight glass bangle units was therefore undertaken to make quantitative estimates of heat stress on exposed workers in the summer season. The thermal data collected confirmed that the heat stress on the workers was severe but measurement of certain physiological indicators revealed relatively low levels of strain amongst the exposed workers. The findings could be attributable to high degrees of acclimatization, but further observations in the field supplemented by studies on simulated exposures of volunteers in a climatic chamber seem to be warranted.  相似文献   
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In the present study the potentials of aqueous extracts of the two plants, neem (Azadirachta indica) and Tulsi (Ocimum sanctum) were examined in alleviating arsenic toxicity in rice (Oryza sativa L.) plants grown in hydroponics. Seedlings of rice grown for 8 days in nutrient solution containing 50 μM sodium arsenite showed decline in growth, reduced biomass, altered membrane permeability and increased production of superoxide anion (O2·−), H2O2 and hydroxyl radicals (·OH). Increased lipid peroxidation marked by elevated TBARS (thiobarbituric acid reactive substances) level, increased protein carbonylation, alterated levels of ascorbate, glutathione and increased activities of enzymes SOD (superoxide dismutase), CAT (catalase), APX (ascorbate peroxidase) and GPX (glutathione peroxidase) were noted in the seedlings on As treatment. Exogenously added leaf aqueous extracts of Azadirachta indica (0.75 mg mL−1, w/v) and Ocimum sanctum (0.87 mg mL−1, w/v) in the growth medium considerably alleviated As toxicity effects in the seedlings, marked by reduced As uptake, restoration of membrane integrity, reduced production of ROS, lowering oxidative damage and restoring the levels of ascorbate, glutathione and activity levels of antioxidative enzymes. Arsenic uptake in the seedlings declined by 72.5% in roots and 72.8% in shoots, when A. indica extract was present in the As treatment medium whereas with O. sanctum extract, the uptake declined by 67.2% in roots and 70.01% in shoots. Results suggest that both A. indica and O. sanctum aqueous extracts have potentials to alleviate arsenic toxicity in rice plants and that A. indica can serve as better As toxicity alleviator compared to O. sanctum.  相似文献   
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Hypertension (HTN) is a devastating disease with a higher incidence in African Americans than European Americans, inspiring searches for genetic variants that contribute to this difference. We report the results of a large-scale admixture scan for genes contributing HTN risk, in which we screened 1,670 African Americans with HTN and 387 control individuals for regions of the genome with elevated proportion of African or European ancestry. No loci were identified that were significantly associated with HTN. We also searched for evidence of an admixture signal at 40 candidate genes and eight previously reported linkage peaks, but none appears to contribute substantially to the differential HTN risk between African and European Americans. Finally, we observed nominal association at one of the loci detected in the admixture scan of Zhu et al. 2005 (p = 0.016 at 6q24.3 correcting for four hypotheses tested), although we caution that the significance is marginal and the estimated odds ratio of 1.19 per African allele is less than what would be expected from the original report; thus, further work is needed to follow up this locus.  相似文献   
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Slow-growing cowpea Rhizobium sp. S2, a pigeon pea isolate, showed excessive synthesis of exopolysaccharide (EPS) and nod factor(s) only when grown in the presence of corresponding host root exudate (RE) or naringenin (a flavonoid present in RE of pigeon pea). muc strain, a plasmid-cured derivative of the parent strain, showed negligible EPS production and failed to synthesize the nod factor(s) under similar growth conditions. The nod factor(s) was extracted and partially purified from the total EPS of the culture supernatant of S2 grown in the presence of either RE or naringenin by the butanol-soluble, ethyl acetate-insoluble method. The parent strain also showed ex-planta nitrogenase activity, whereas in muc it was not detectable. In contrast to observations of the location of nod, nif- and EPS-synthesizing genes on the chromosome in commonly studied cowpea Rhizobia and Bradyrhizobium sp. colony blot and dot blot hybridization studies revealed the presence of nod (common nod genes), nif (nif KDH); and EPS (pss) determinants to be on the large plasmid in the parent strain and therefore absent in muc, which is a plasmid-cured derivative. Received: 10 June 1997 / Accepted: 11 July 1997  相似文献   
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The 2 S seed storage protein, sunflower albumin 8, contains an unusually high proportion of hydrophobic residues including 16 methionines in a mature protein of 103 amino acids. A structural model, based on the known structure of a related protein, has been constructed as a four-helix bundle cross-linked by four disulphide bonds. This model structure is consistent with data from circular dichroism and nuclear magnetic resonance experiments. Analysis of the model's surface shows the presence of a large hydrophobic face that may be responsible for the highly stable emulsions this protein is known to form with oil/water mixtures.  相似文献   
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The aim of the present study was to evaluate the characteristics of the circadian rest‐activity rhythm of cancer patients. Thirty‐one in‐patients, consisting of 19 males and 12 females, were randomly selected from the Regional Cancer Center, Pandit Jawaharlal Nehru Medical College, Raipur, India. The rest‐activity rhythm was studied non‐invasively by wrist actigraphy, and compared with 35 age‐matched apparently healthy subjects (22 males and 13 females). All subjects wore an Actiwatch (AW64, Mini Mitter Co. Inc., USA) for at least 4–7 consecutive days. Fifteen‐second epoch length was selected for gathering actigraphy data. In addition, several sleep parameters, such as time in bed, assumed sleep, actual sleep time, actual wake time, sleep efficiency, sleep latency, sleep bouts, wake bouts, and fragmentation index, were also recorded. Data were analyzed using several statistical techniques, such as cosinor rhythmometry, spectral analysis, ANOVA, Duncan's multiple‐range test, and t‐test. Dichotomy index (I<O) and autocorrelation coefficient (r24) were also computed. The results validated a statistically significant circadian rhythm in rest‐activity with a prominent period of 24 h for most cancer patients and control subjects. Results of this study further revealed that cancer patients do experience a drastic alteration in the circadian rest‐activity rhythm parameters. Both the dichotomy index and r24 declined in the group of cancer patients. The occurrence of the peak (acrophase, Ø) of the rest‐activity rhythm was earlier (p<0.001) in cancer patients than age‐ and gender‐matched control subjects. Results of sleep parameters revealed that cancer patients spent longer time in bed, had longer assumed and actual sleep durations, and a greater number of sleep and wake bouts compared to control subjects. Further, nap frequency, total nap duration, average nap, and total nap duration per 1 h awake span were statistically significantly higher in cancer patients than control subjects. In conclusion, the results of the present study document the disruption of the circadian rhythm in rest‐activity of cancer in‐patients, with a dampening of amplitude, lowering of mean level of activity, and phase advancement. These alterations of the circadian rhythm characteristics could be attributed to disease, irrespective of variability due to gender, sites of cancer, and timings of therapies. These results might help in designing patient‐specific chronotherapeutic protocols.  相似文献   
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Kinetin, a cytokinin which promotes seed germination by inhibiting the action of abscisic acid, is an important molecule known to trigger various molecular mechanisms by interacting with an array of proteins shown from experimental observations in various model organisms. We report here the prediction of most probable protein targets of kinetin from spinach proteome using in silico approaches. Inverse docking and ligand-based similarity search was performed using kinetin as molecule. The former method prioritized six spinach proteins, whereas the latter method provided a list of protein targets retrieved from several model organisms. The most probable protein targets were selected by comparing the rank list of docking and ligand similarity methods. Both of these methods prioritized chitinase as the most probable protein target (ΔGpred = 5.064 kcal/mol) supported by the experimental structure of yeast chitinase 1 complex with kinetin (PDB: 2UY5) and Gliocladium roseum chitinase complex with 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione (caffeine; 3G6M) which bears a 3D similarity of 0.43 with kinetin. An in vitro study to evaluate the effect of kinetin on spinach seed germination indicated that a very low concentration of kinetin (0.5 mg/l) did not show a significant effect compared to control in inducing seed germination process. Further, higher levels of kinetin (>0.5 mg/l) constituted an antagonist effect on spinach seed germination. It is anticipated that kinetin may have a molecular interaction with prioritized protein targets synthesized during the seed germination process and reduces growth. Thus, it appears that kinetin may not be a suitable hormone for enhancing spinach seed germination in vitro.

Electronic supplementary material

The online version of this article (doi:10.1007/s12154-015-0135-3) contains supplementary material, which is available to authorized users.  相似文献   
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