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71.
72.
Photochemical efficiency, photosynthetic capacity, osmoprotectants, and relative water content (RWC) were recorded in saplings
of two evergreen plants (Boehmeria rugulosa Wedd. and Olea glandulifera Wall. ex G. Don) grown inside (GL) and outside (OP) a glasshouse during the winter season. The OP plants experienced 2.0–2.5 °C lower
air temperature and dew formation in comparison to GL plants. Diurnal observations indicated no change in RWC in the leaves
of GL and OP plants, while significant reduction in both transpiration and net photosynthetic (P
N) rates was observed in OP plants: the reduction in P
N was much more prominent as was also reflected by poor water use efficiency of these plants. Similarly, OP plants also showed
decrease in the apparent quantum yield and irradiance-saturated CO2 assimilation rate. The decrease in P
N was not associated with decreased stomatal conductance. However, a significant reduction in the ratio of variable to maximum
chlorophyll (Chl) fluorescence (Fv/Fm) and Chl content was recorded in the OP plants which also contained more total soluble saccharides but less proline contents.
The greater enhancement of P
N at 15 °C in comparison to measurements taken at 10 °C in OP plants over GL plants probably indicated an increase in mesophyll
capacity of the OP plants’ growth at increased temperature. Hence the enhanced growth and productivity of plants grown in
sheltered environments could be associated to their higher photosynthetic activity that may have important bearing on their
field establishment and productivity in the long run. The response varied with plant species; reduction in P
N was greater in B. rugulosa than in O. glandulifera. However, the recovery of OP plants in terms of Fv/Fm in the subsequent months revealed that photosynthetic system of these plants is revocable. 相似文献
73.
Vipin Kumar Sharma Khomendra Kumar Sarwa Bhaskar Mazumder 《Journal of liposome research》2014,24(2):83-89
Liposomes are well known lipid carriers for drug delivery of bioactive molecules encapsulated inside their membrane. Liposomes as skin drug delivery systems were initially promoted primarily for localized effects with minimal systemic delivery. Subsequently, a novel vesicular system, transferosomes was reported for transdermal delivery with efficiency similar to subcutaneous injection. The multiple bilayered organizations of lipids applied in these vesicles structure are somewhat similar to complex nature of stratum corneal intercellular lipids domains. The incorporation of novel agents into these lipid vesicles results in the loss of entrapped markers but it is similar to fluidization of stratum corneum lipids on treatment with a penetration enhancer. This approach generated the utility of penetration enhancers/fluidizing agents in lipids vesicular systems for skin delivery. For the transdermal and topical applications of liposomes, fluidity of bilayer lipid membrane is rate limiting which governs the permeation. This article critically reviews the relevance of using different types of vesicles as a model for skin in permeation enhancement studies. This study has also been designed to encompass all enhancement measurements and analytical tools for characterization of permeability in liposomal vesicular system. 相似文献
74.
75.
Bhaskar?Mukhopadhyayprivatemiaaow@rediffmail.com" title="b.mukhopadhyay@vsnl.com privatemiaaow@rediffmail.com" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《Dialectical Anthropology》2005,29(1):35-60
This article seeks to document the vernacular perceptions of ‘globalization’ in rural Bengal (India) and, in that connection,
seeks to rethink some long-held western notions concerning commodity, consumption, representation, the nature of sociality
and the politics of democratic empowerment in the third-world. In the subaltern imaginary, images seem to play a crucial role
conductive to empowerment. Also, far from resisting globalization and consumption, the rural poor seems to have assimilated
these into their vernacular cosmology.
In memoriam: Gourkishore Ghosh (1923–2001) Vernacular intellectual, publicist, crusader for free speech and democracy 相似文献
76.
Chandra M Tschirgi ML Tardiff JC 《American journal of physiology. Heart and circulatory physiology》2005,289(5):H2112-H2119
How different mutations in cardiac troponin T (cTnT) lead to distinct secondary downstream cellular remodeling in familial hypertrophic cardiomyopathy (FHC) remains elusive. To explore the molecular basis for the distinct impact of different mutations in cTnT on cardiac myocytes, we studied mechanical activity of detergent-skinned muscle fiber bundles from different lines of transgenic (TG) mouse hearts that express wild-type cTnT (WTTG), R92W cTnT, R92L cTnT, and Delta-160 cTnT (deletion of amino acid 160). The amount of mutant cTnT is approximately 50% of the total myocellular cTnT in both R92W and R92L TG mouse hearts and approximately 35% in Delta-160 TG mouse hearts. Myofilament Ca2+ sensitivity was enhanced in all mutant cTnT TG cardiac muscle fibers. Compared with the WTTG fibers, Ca2+ sensitivity increased significantly at short sarcomere length (SL) of 1.9 microm (P < 0.001) in R92W TG fibers by 2.2-fold, in R92L by 2.0-fold, and in Delta-160 by 1.3-fold. At long SL of 2.3 microm, Ca2+ sensitivity increased significantly (P < 0.01) in a similar manner (R92W, 2.5-fold; R92L, 1.9-fold; Delta-160, 1.3-fold). Ca2+-activated maximal tension remained unaltered in all TG muscle fibers. However, tension-dependent ATP consumption increased significantly in Delta-160 TG muscle fibers at both short SL (23%, P < 0.005) and long SL (37%, P < 0.0001), suggesting a mutation-induced change in cross-bridge detachment rate constant. Chronic stresses on relative cellular ATP level in cardiac myocytes may cause a strain on energy-dependent Ca2+ homeostatic mechanisms. This may result in pathological remodeling that we observed in Delta-160 TG cardiac myocytes where the ratio of sarco(endo)plasmic reticulum Ca2+-ATPase 2/phospholamban decreased significantly. Our results suggest that different types of stresses imposed on cardiac myocytes would trigger distinct cellular signaling, which leads to remodeling that may be unique to some mutants. 相似文献
77.
Chandra P. Prasad Gayatri Rath Sandeep Mathur Dinesh Bhatnagar Ranju Ralhan 《Chemico-biological interactions》2009,181(2):263-271
Abnormal activation of the Wnt/β-catenin signaling pathway and subsequent upregulation of β-catenin driven downstream targets—c-Myc and cyclin D1 is associated with development of breast cancer. The objective of our study was to determine if curcumin could modulate the key elements of Wnt pathway in breast cancer cells; an effect that might underscore its usefulness for chemoprevention/treatment of this malignancy. Curcumin showed a cytotoxic effect on MCF-7 cells with 50% inhibitory concentration (IC50) of 35 μM; while IC50 for MDA-MB-231 cells was 30 μM. Treatment with low cytostatic dose of 20 μM curcumin showed G2/M arrest in both breast cancer cells. The effect of curcumin (20 μM) treatment on expression of Wnt/β-catenin pathway components in breast cancer cells (MCF-7 and MDA-MB-231) was analyzed by immunofluorescence and Western blotting. Curcumin was found to effectively inhibit the expression of several Wnt/β-catenin pathway components—disheveled, β-catenin, cyclin D1 and slug in both MCF-7 and MDA-MB-231. Immunofluorescence analysis showed that curcumin markedly reduced the nuclear expression of disheveled and β-catenin proteins. Further, the protein levels of the positively regulated β-catenin targets—cyclin D1 and slug, were downregulated by curcumin treatment. The expression levels of two integral proteins of Wnt signaling, GSK3β and E-cadherin were also altered by curcumin treatment. In conclusion, our data demonstrated that the efficacy of curcumin in inhibition of cell proliferation and induction of apoptosis might occur through modulation of β-catenin pathway in human breast cancer cells. 相似文献
78.
M. Subhosh Chandra Buddolla Viswanath B. Rajasekhar Reddy 《Indian journal of microbiology》2007,47(4):323-328
The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory
scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports
for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days.
The peak production of the enzymes occurred within 3 days of incubation. Among solid supports used in the study, wheat bran
was the best solid matrix followed by groundnut fodder in production of cellulolytic enzymes in solid state fermentation.
Groundnut fodder supported significant production of FPase (2.09 FPU/g), CMCase (1.36 U/g) and -glucosidase activity (0.0117
U/g) in solid state fermentation. Considerable secretion of protein (5.10 mg/g) on groundnut fodder at peak time interval
1st day of incubation was recorded. 相似文献
79.