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41.
42.
K C Srivastava 《Prostaglandins, leukotrienes, and essential fatty acids》1989,35(3):183-185
The effects of onion and ginger consumption on platelet thromboxane production were examined. Volunteers, all Danish women, consumed either 70 g raw onion or 5 g raw ginger daily for a period of 7 days. Each participant in each (onion or ginger) group served as her own control. TxB2 determination was made in serum obtained after blood clotting. The following are the results. TxB2 (pmol/ml serum): (i) onion group--before consumption 910 +/- 327, after consumption 1005 +/- 713 (Mean +/- SD, N = 5); (ii) ginger consumption 782 +/- 482, after consumption 498 +/- 164 (Mean +/- SD, N = 7). 相似文献
43.
A K Srivastava C Pandey K P Dwivedi V K Singh 《Indian journal of biochemistry & biophysics》1989,26(3):199-200
QSAR studies have been performed on the homologues of 3-triazines, using molecular connectivity index and van der Waal volume as structural parameters. The regression analysis has shown good correlation between antitumour activity and the two structural parameters. 相似文献
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45.
Biochemical changes in the zona pellucida of rabbit ova induced by fertilization and sperm enzymes 总被引:2,自引:0,他引:2
46.
Avinash Chandra Srivastava Ashok Kumar Tiku Madan Pal 《Acta Physiologiae Plantarum》2006,28(2):181-188
This study was conducted to determine reciprocal effects of low to high doses of nitrogenous fertilizer (N30, N40, N50, N60 and N70 — 30, 40, 50, 60 and 70 kg ha−1 respectively) and CO2 enriched environment on C and N partitioning in soybean (Glycine max (L.) Merril cv JS-335). Plants were grown from seedling emergence to maturity inside open top chambers under ambient, AC
(350±50 mol mol−1) and elevated, EC (600±50 mol mol−1) CO2 and analyzed at seedling, vegetative, flowering, pod setting and maturity stages. Soybean responded to both CO2 enrichment and N supply. Leaves, stem and root reserves at different growth stages were analyzed for total C and N contents.
Consistent increase in the C contents of the leaf, stem and root was observed under EC than in AC. N contents in the different
plant parts were found to be decreased under EC-grown plants specially at seedling and vegetative stage despite providing
N doses to the soil. Significant increase observed for C to N dry mass ratio under EC in the root, stems and leaves at seedling
and vegetative stage was decreased in the middle and later growth stages possibly due to combined impact of N doses to the
soil and increased N2 fixing activities due to EC conditions. Critical analysis of our findings reveals that the composition and partitioning of
C and N of soybean under variable rates of N supply and CO2 enrichment alter according to need under altered metabolic process. These changes eventually may lead to alteration in uptake
of not only N but other essential nutrients also under changing atmosphere. 相似文献
47.
Erin K. Nyren-Erickson Justin M. Jones D.K. Srivastava Sanku Mallik 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
A disintegrin and metalloproteinase-12 (ADAM12) is a member of the greater ADAM family of enzymes: these are multifunctional, generally membrane-bound, zinc proteases for which there are forty genes known (21 of these appearing in humans). ADAM12 has been implicated in the pathogenesis of various cancers, liver fibrogenesis, hypertension, and asthma, and its elevation or decrease in human serum has been linked to these and other physiological/pathological conditions.Scope
In this review, we begin with a brief overview of the ADAM family of enzymes and protein structure. We then discuss the role of ADAM12 in the progression and/or diagnosis of various disease conditions, and we will conclude with an exploration of currently known natural and synthetic inhibitors.Major conclusion
ADAM12 has potential to emerge as a successful drug target, although targeting the metalloproteinase domain with any specificity will be difficult to achieve due to structural similarity between the members of the ADAM and MMP family of enzymes. Overall, more research is required to establish ADAM12 being as a highly desirable biomarker and drug target of different diseases, and their selective inhibitors as potential therapeutic agents.General significance
Given the appearance of elevated levels of ADAM12 in various diseases, particularly breast cancer, our understanding of this enzyme both as a biomarker and a potential drug target could help make significant inroads into both early diagnosis and treatment of disease. 相似文献48.
Shivani Srivastava David Pelloso Hailin Feng Larry Voiles David Lewis Zdenka Haskova Margaret Whitacre Stephen Trulli Yi-Jiun Chen John Toso Zdenka L. Jonak Hua-Chen Chang Michael J. Robertson 《Cancer immunology, immunotherapy : CII》2013,62(6):1073-1082
The antitumor activity of monoclonal antibodies is mediated by effector cells, such as natural killer (NK) cells, that express Fc receptors for immunoglobulin. Efficacy of monoclonal antibodies, including the CD20 antibody rituximab, could be improved by agents that augment the function of NK cells. Interleukin (IL)-18 is an immunostimulatory cytokine that has antitumor activity in preclinical models. The effects of IL-18 on NK cell function mediated through Fcγ receptors were examined. Human NK cells stimulated with immobilized IgG in vitro secreted IFN-γ as expected; such IFN-γ production was partially inhibited by blocking CD16 with monoclonal antibodies. IL-18 augmented IFN-γ production by NK cells stimulated with immobilized IgG or CD16 antibodies. NK cell IFN-γ production in response to immobilized IgG and/or IL-18 was inhibited by chemical inhibitors of Syk and several other kinases involved in CD16 signaling pathways. IL-18 augmented antibody-dependent cellular cytotoxicity (ADCC) of human NK cells against rituximab-coated Raji cells in vitro. IL-18 and rituximab acted synergistically to promote regression of human lymphoma xenografts in SCID mice. Inasmuch as IL-18 costimulates IFN-γ production and ADCC of NK cells activated through Fc receptors in vitro and augments antitumor activity of rituximab in vivo, it is an attractive cytokine to combine with monoclonal antibodies for treatment of human cancer. 相似文献
49.
L. T. Ellis A. K. Asthana P. Srivastava I. Omar K. K. Rawat V. Sahu 《Journal of bryology》2013,35(1):47-63
AbstractBryophyte biomass and diversity vary strongly with altitude in the tropics. Low abundance and low species numbers in lowland rain forests are most likely due to reduced diurnal activity times combined with high nocturnal respiration rates at high temperatures. This may exclude many montane species from the warm lowlands. However, an alternative hypothesis explains the observed pattern, namely a limited desiccation tolerance of montane species, precipitation being more concentrated but less frequent in most lowland forests compared to montane cloud forests. To test this hypothesis, we studied the desiccation tolerance of four montane and four lowland bryophyte species. The effects of prolonged drought were quantified with chlorophyll fluorescence (Fv/Fm) and the extent of electrolyte leakage. Both montane and lowland species survived dry periods of ≧80 days, which far exceeds the duration of dry periods in the wet lowland tropics. We can thus exclude intolerance to long dry spells as an explaination for the absence of the tested montane species in the lowlands. We should continue to focus on other mechanisms to explain the altitudinal gradient of bryophyte abundance and diversity in the tropics, in order to understand this pattern, as well as to predict future trends under climatic warming. 相似文献
50.