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81.
Agnihotri VK Thappa RK Meena B Kapahi BK Saxena RK Qazi GN Agarwal SG 《Phytochemistry》2004,65(16):2411-2413
Fresh aerial parts of Angelica glauca, growing wild in Kashmir valley in higher Himalaya (Jammu and Kashmir, India), collected at flowering stage from different locations, on hydro-distillation provided a refreshing light pale coloured essential oil with characteristic floral woody flavour. The oil was found to be a complex mixture of mono- and sesquiterpenes and 34 compounds accounting for nearly 97.4% of the oil were characterized with the help of capillary GC, GC-MS, and NMR. Major compounds of the oil were characterized as alpha-phellandrene (13.5%), trans-carveol (12.0%), beta-pinene (11.7%), thujene (7.5%), beta-caryophyllene oxide (7.2%), beta-caryophyllene (7.0%), gamma-terpinene (6.7%), nerolidol (6.5%), beta-bisabolene (5.2%) and germacrene D (4.5%). It is the first report to exploit the essential oil from Himalayan A. glauca herb collected at flowering stage. 相似文献
82.
Mandwal AK Tripathi CK Trivedi PD Joshi AK Agarwal SC Bihari V 《Biotechnology letters》2004,26(3):217-221
Conversion of benzaldehyde to L-phenylacetyl carbinol (L-PAC) was achieved with immobilized, growing cells of Saccharomyces cerevisiae in different reactors. Product formation increased (31%) with the subsequent initial reuses of the entrapped cells. Biomass production and PAC formation depleted (40 and 57%, respectively) after 4-5 continuous growth and biotransformation cycles. With the regeneration of the biocatalysts, catalytic activity of the cells was resumed. The highest yields were in a stirred tank reactor (29 g PAC) from 77 g benzeldehyde with 14 repeated uses of entrapped cells. 相似文献
83.
84.
The phenolic activity (log 1/C) of a large series of phenols against L1210 leukaemia cells was modelled using physicochemical parameters other than conventional electronic and steric parameters. Attempts have also been made to examine need or otherwise of the hydrophobic parameter, log P, in such studies. The results have shown that contribution of log P in modelling log 1/C is favourable. 相似文献
85.
S.?L.?KothariEmail author Kalpana?Agarwal Satish?Kumar 《In vitro cellular & developmental biology. Plant》2004,40(5):515-519
Summary Growth and morphogenesis of plant tissues under in vitro conditions are largely influenced by the composition of the culture media. In this study, effects of different inorganic
nutrients (ZnSO4 and CuSO4) on callus induction and plant regeneration of Eleusine coracana in vitro were examined. Primary callus induction without ZnSO4 resulted in improved shoot formation upon transfer of calluses to normal regeneration medium. CuSO4 increased to 5x the normal concentration in the media for primary seed callus induction and plant regeneration resulted in
a 4-fold increase in number of regnnerated shoots. For long-term callus cultures, 2x KNO3 or 4x Fe-EDTA could replace the requirement for α-naphthaleneacetic acid in the regeneration medium, while 60 μM ZnSO4 or 0.5 μM CuSO4 was optimal for plant regeneration from callus cultures. 相似文献
86.
Mouse peritoneal macrophages (MPM) when elicited by the antioxidant ascorbic acid have been found to be significantly stimulatory, exhibiting marked alteration at the cellular and enzyme levels. Alterations recorded were as follows--cellular yield per mouse, their protein content, lysosomal acid hydrolase levels and capability to phagocyte, all were significantly enhanced. The new stimulant was observed to produce no synergistic action on MPM when thioglycollate, BCG or endotoxin along with the same stimulated the latter. Levels of antioxidants like ascorbic acid and glutathione were found to be enhanced in elicited macrophages whereas superoxide dismutase levels varied when the three above stimulators were administered. However, the ascorbic acid elicited cells showed an increase in glutathione levels and a decrease in SOD levels but no change in total intracellular ascorbic acid levels. Further, though ascorbic acid interaction enhanced the phagocytic capability of MPM as compared to resident cells, no significant boosting of phagocytic process could be observed when each of three stimulators coupled with ascorbic acid was used for macrophage elicitation. 相似文献
87.
Alam SI Agarwal GS Kamboj DV Rai GP Singh L 《Indian journal of experimental biology》2003,41(2):177-180
A sensitive PCR based detection of Bacillus anthracis spores from environnment was standardized. Specific 1247bp amplicon could be detected with template concentration as low as 13 pg. Sensitivity was enhanced to 10 fold by nesting with second set of primers, forming 208bp amplicon. Extraction of DNA from spores purified from soil samples by aqueous polymer two-phase system followed by partial germination and freeze-thaw treatment yielded best results. Soil sample spiked with spores (8x10(2)/g of sample) could be detected with this method. 相似文献
88.
Forty-five patients presenting with high-energy open grade III tibial diaphyseal fractures were treated with the Ilizarov technique. Of these patients, 28 required plastic surgical intervention for achieving wound closure. Most of the injuries were complicated by initial neglect and inadequate primary soft-tissue coverage resulting in osteitis, sequestration, and segmental diaphyseal tibial defects, often in combination with skin-envelope deficits of various types in and around the fracture perimeter. The unique soft-tissue problems encountered while using the Ilizarov fixator have not been focused on in previous reports on the management of segmental bone defects. Four basic local flap procedures: the transposition flap, rotation flap, adipofascial turnover flap, and Z-plasty are useful and versatile for managing most types and grades of soft-tissue defects associated with a segmental bone loss with the Ilizarov technique. 相似文献
89.
90.
Cytotoxic factor-autoantibodies: possible role in the pathogenesis of dengue haemorrhagic fever 总被引:4,自引:0,他引:4
Chaturvedi UC Elbishbishi EA Agarwal R Mustafa AS 《FEMS immunology and medical microbiology》2001,31(3):181-186
During dengue virus infection a unique cytokine, cytotoxic factor (hCF), is produced that is pathogenesis-related and plays a key role in the development of dengue haemorrhagic fever (DHF). However, what regulates the adverse effects of hCF is not known. We have previously shown that anti-hCF antibodies raised in mice, neutralise the pathogenic effects of hCF. In this study we have investigated the presence and levels of hCF-autoantibodies in sera of patients with various severity of dengue illness (n=136) and normal healthy controls (n=50). The highest levels of hCF-autoantibodies (mean+/-S.D.=36+/-20 U ml(-1)) were seen in patients with mild illness, the dengue fever (DF), and 48 out of 50 (96%) of the sera were positive. On the other hand the hCF-autoantibody levels declined sharply with the development of DHF and the levels were lowest in patients with DHF grade IV (mean+/-S.D.=5+/-2 U ml(-1); P=<0.001 as compared to DF). Only one of the 13 DHF grade IV patients had an antibody level above the 'cut-off' value (mean plus 3 S.D. of the control sera). The analysis of data with respect to different days of illness further showed that the highest levels of hCF-autoantibodies were present in DF patients at >9 days of illness. Moreover, the DF patients at all time points, i.e. 1-4, 5-8 and >9 days of illness had significantly higher levels of hCF-autoantibodies (P<0.001) than patients with DHF grade I, II, III and IV. In addition DHF grade I and grade II patients had significantly more positive specimens than DHF grade III and grade IV patients at all time points. These results suggest that elevated levels of hCF-autoantibodies protect the patients against the development of severe forms of DHF and, therefore, it may be useful as a prognostic indicator. 相似文献