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811.
Shashi Dhingra B. Bhatia G. S. Chhina Baldev Singh 《International journal of biometeorology》1987,31(3):191-199
Freezing incidence and tissue loss on exposure of hind limbs of female Wistar rats to freezing mixture was reduced by demedullation 6 days prior to cold exposure (p<0.01 and p<0.001 respectively); demedullation 1 h after freezing injury had no effect on tissue loss. Noradrenaline (1 mg/kg i.p.) 5 min before exposure increased the freezing incidence in intact (p<0.05) as well as in demedullated rats (p<0.01), with no effect on tissue loss. Adrenaline (500 mg/kg i.p.) had no effect on either. A sustained fall in plasma adrenaline after demedullation leading to reduced reactivity of the blood vessels to some vasoactive agents is postulated. 相似文献
812.
S. N. Mehta P. C. Gangwar R. K. Srivastava D. P. Dhingra 《International journal of biometeorology》1981,25(3):199-203
Forty-five healthy lactating buffaloes were taken for this study in three groups: group 1 served as control. At 11:00 and 15:00 h daily the animals in group 2 were given showers and of group 3 were sent for wallowing for half an hour each time. Blood samples were taken at 14-day intervals. The overall mean values of acid phosphatase, alkaline phosphatase, total plasma ascorbic acid and plasma proteins were 2.61, 2.87, 2.89 (KA U/100ml plasma); 4.81, 4.71, 4.51 (KA U/100 ml plasma), 1.04, 1.29, 1.41 (mg/100ml plasma) and 7.05, 6.17, 6.05 (g/100 ml plasma) in control, shower and wallow groups respectively. The different parameters of reproductive efficiency-percentage of animals coming in oestrus, days-open, duration of oestrus, percent conception rate and services per conception were 40, 60, 19.09, 20, 7 in the controlgroup; 53.33, 42, 19.46, 28.50, 4.25 in the shower group and 73.33, 38.75, 23.00, 50 and 2.00 in the wallow group respectively. 相似文献
813.
K. Byju V. Anuradha Emilda Rosmine N. C. Kumar S. M. Nair 《Journal of plant biochemistry and biotechnology.》2013,22(3):304-311
The composition of the lipophilic extract from Hydrilla verticillata, the common aquatic weed collected from Sasthamkotta Lake, the largest freshwater lake in Kerala, south of the west coast of India, was investigated. The lake is a designated wetland of international importance under the Ramsar Convention since 2002. GC-MS study of the unsaponifiable lipophilic extract of H. verticillata confirmed the presence of 3,5,11,15-tetramethyl 1- hexadecen-3-ol (C20H40O) and phytol (C20H40O) as major components, and their structures were elucidated. Phytol and 3,5,11,15-tetramethyl 1- hexadecen3-ol are the two isomers of the diterpeneol (C20H40O) found in the unsaponifible lipophilic extract of H. verticillata and are formed by the hydrolysis of the alcohol moiety of chlorophyll. On quantification, an appreciable concentration of phytol (6.39 g?Kg?1) was estimated. The feasibility to utilize H. verticillata to produce phytol is to be addressed by further studies since H. verticillata is considered as one of the world’s fast widely spread aquatic weeds on account of its numerous mechanisms of vegetative reproductions. 相似文献
814.
815.
The intramolecular conformation of puromycin, a broad spectrum antibiotic, in solution has been investigated by proton magnetic resonance (PMR) spectroscopy. A comparison of the proton chemical shift and proton-proton coupling constant data of puromycin with puromycin aminonucleoside suggests that puromycin in solution exists as an equilibrium blend of extended and folded conformers. These folded conformers are the result of flexibility around the C alpha -C beta bond of the aminoacyl segment of puromycin. One of the folded conformers predicted by PMR is in excellent agreement with the x-ray data. 相似文献
816.
Michael J Moore Amit Dhingra Pamela S Soltis Regina Shaw William G Farmerie Kevin M Folta Douglas E Soltis 《BMC plant biology》2006,6(1):17-13
Background
Plastid genome sequence information is vital to several disciplines in plant biology, including phylogenetics and molecular biology. The past five years have witnessed a dramatic increase in the number of completely sequenced plastid genomes, fuelled largely by advances in conventional Sanger sequencing technology. Here we report a further significant reduction in time and cost for plastid genome sequencing through the successful use of a newly available pyrosequencing platform, the Genome Sequencer 20 (GS 20) System (454 Life Sciences Corporation), to rapidly and accurately sequence the whole plastid genomes of the basal eudicot angiosperms Nandina domestica (Berberidaceae) and Platanus occidentalis (Platanaceae). 相似文献817.
V. Thirunavukkarasu A. T. Anitha Nandhini C. V. Anuradha 《Experimental diabetes research》2004,5(4):237-244
Nonenzymatic glycation of proteins, leading to chemical
modification and cross-linking are of importance in the
pathology of diabetic complications.We studied the effect of
α-lipoic acid (LA) on the content and characteristics of the
protein collagen from skin of high-fructose fed rats. The
rats were divided into 4 groups of 6 each. Two groups of
rats were fed with a high fructose diet (60 g/100 g diet) and
administered either LA (35 mg/kg b.w., i.p) (FRU+LA) or
0.2 ml vehicle (saline) (FRU) for 45 days. The other 2 groups
were fed with control diet containing starch (60 g/100 g
diet) and administered either saline (CON) or lipoic acid
(CON+LA). The rats were maintained for 45 days and then
sacrificed. Plasma glucose, insulin, fructosamine, protein
glycation, and blood glycated hemoglobin (HbA1C) were
measured. Collagen was isolated from skin and the physicochemical
properties of collagen were studied. Fructose administration
caused accumulation of collagen in skin. Extensive
cross-linking was evidenced by enhanced glycation
and AGE-linked fluorescence. Increased peroxidation and
changes in physicochemical properties such as shrinkage
temperature, aldehyde content, solubililty pattern, susceptibility
to denaturing agents were observed in fructose-fed
rats. SDS gel pattern of collagen from these rats showed
elevated β component of type I collagen. These changes
were alleviated by the simultaneous administration of LA.
Administration of LA to fructose-fed rats had a positive
influence on both quantitative and qualitative properties of collagen. The results suggest a mechanism for the ability
of LA to delay diabetic complications. 相似文献
818.
The experimentally observed geometry of a miniature double helix of high anti (χCN fixed ? 120°) nucleic acid structure indicates substantial interstrand base stacking with little intrastrand base stacking. This geometry is consistent with the right-handed vertical double helix in which the base planes are parallel to helical axis proposed by Olson [(1977) Proc. Natl. Acad. Sci. USA 74 , 1775] from theoretical calculations. The experimental data do not agree with the left-handed model in which the base planes are perpendicular to helical axis that has been proposed by Yathindra and Sundaralingam [(1976) Nucl. Acids Res. 3 , 729]. The theoretically computed chemical shift changes for the various double-helical configurations show that for the system examined, only the vertical model can explain the experimentally observed shift trends. The melting curve for the helix–coil transition for high anti dinucleoside monophosphate has been observed for the first time. Even though the experimental data support vertical double helices when χCN is fixed at 120°, data on naturally occurring nucleic acid structures indicate that they have no proclivity to enter into vertically stabilized double-helical arrays. 相似文献
819.
Anuradha Upadhyay T. Mohapatra R. A. Pai R. P. Sharma 《Journal of plant biochemistry and biotechnology.》1996,5(1):17-22
In Brassica juncea, segregation of 44 RFLP markers generated by homologous genomic DNA clones as probes was studied in a F2 population obtained from an intervarietal cross. Linkage relationship among the markers was established using computer package ‘MAPMAKER’. Twenty five of the markers could be arranged in nine linkage groups, covering a total of 243.3 cM. Marker BJG357c showed tight linkage (3.9 cM) with yellow seed coat colour locus (r 1). Based on single factor analysis of variance,17 significant marker-trait associations could be established in respect of six quantitative traits viz. days to flowering, plant height, number of primary branches, secondary branches per primary branch, siliquea per secondary branch, and seeds per siliqua. The proportion of phenotypic variation explained by individual marker-trait association ranged from 3.0% to 33.2%. The putative gene action at majority of the marked genomic regions was found to be partial dominance to dominance. 相似文献