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81.
Irradiation with X-rays and gamma rays reduced the speed of germination of seeds of jute cultivars,viz., JRO 632, JRO 620, Sudan Green ofCorchorus olitorius and JRC 212, Fanduk, D 154 ofC. capsularis. Though the first phase of germination(i.e. seed variability) remained apparently unaffected, the second phase (i.e. the sprouting ability) and the third phase(i.e. the attainment of autotrophic status) were found to be the best indicators of radiation injury and provided dependable data for the assessment of radiosensitivity. The jute cultivars have not shown accountable intervarietal differences in radiosensitivity in respect of LD 50 and LD 100 for the second and the third phases of germination. 相似文献
82.
Morphological variability of the human chromosomes in two Indian populations - Rajputs and Punjabis.
Karotypic evaluation of 100 Rajputs and 100 Punjabis revealed different frequencies of Y chromosome polymorphism and minor chromosome variants. Long Y chromosome were observed 5% of the Rajputs and 3% of the Punjabis. The Y indices of Rajputs were consistently higher than those of Punjabis. Significant differences were noted between Rajputs and Punjabis with respect to the 5 Y indices. Significant differences were also found when those 2 populations were compared with different populations of the world. Minor chromosome variants were observed in 18% of the Rajputs and 19% of the Punjabis. 相似文献
83.
A potential enzymic mechanism for the degradation of glycosaminogly cans was characterised using enzymes found in rheumatoid synovial fluid from the knee joint. This mechanism involves a true hyluronidase together with the concerted action of beta-glucuronidase and beta-N-acetylhexosaminidase. The contribution of the exopolysaccharidases to hyaluronate degradation was demonstrated by the use of specific inhibitors, while the distinct identity of a true hyaluronidase was shown by ammonium sulphate and agarose gel column fractionations. Only the hyluronidase fraction was capable of degrading high molecular weight hyaluronate. The exopolysaccharidase activities were shown to be markedly elevated in rheumatoid as compared to osteoarthritic synovial fluid and also normal serum. On the other hand, hyluronidase was similarly active in rheumatoid and osteoarthritic synovial fluids; both these levels were lower than that of normal human serum. Hyaluronidase in synovial fluid may thus be derived by diffusion from serum, since it is of relatively low molecular weight (60 000). The pH requirements of this enzyme system and the strong inhibition of hyaluronidase by synovial fluid make it unlikely that the mechanism operates extracellularly. It is proposed that as a lysosomal mechanism, however, it is an important contributing factor in the chronic erosion process characteristic of rheumatoid arthritis. 相似文献
84.
Very low density and high density lipoproteins have been isolated from human plasma and their interaction with 1-anilin0-8-naphthalene sulfonate has been studied under different conditions of pH and added salt. Intrinsic fluorescence of bound 1-anilino-8-naphthalene sulfonate was higher for high density lipoproteins then for very low density lipoproteins, but was unaffected by salt in both systems. Binding of 1-anilino-8-naphthalene sulfonate by both these lipoproteins was saturable and was higher in the presence of added NaCl or CaCl2, Ca2+ having a greater effect than Na+ in enhancing fluorescence. The binding data were analyzed by Scatchard plots; the number of binding sites and the affinity of 1-anilino-8-naphthalene sulfonate for the site increased with increasing salt concentration. Fluorescence pH curves were similar to those published for phospholipids. From these and previous observations it is suggested that the phospholipids probably represent the major binding sites for 1-anilino-8-naphthalene sulfonate. 相似文献
85.
The effect of 3-(3,4-dihydro-6-methoxy-2-naphthyl)-2,2-dimethyl-pentanoic acid, a potent nonsteroidal antifertility compound, on the uptake of estradiol-17beta-6, 7-tritiated in vitro in the rat uterus was studied. The estradiol uptake of estrogen-primed and compound-treated groups were the same. When estradiol and the compound were present in medium at the same time, estradiol uptake was significantly (p less than .01) increased. The results indicate that the compound synergizes the effect of estradiol. 相似文献
86.
87.
Spin-lattice relaxation in the triplet state of the buried tryptophan residue of ribonuclease T1. 下载免费PDF全文
The individual spin-lattice relaxation (SLR) rate constants (Wij) between the lowest triplet sublevels of the lone tryptophan residue buried in the interior of the globular protein ribonuclease T1 have been reported in the temperature range 1.2 to 3.0 K in zero applied magnetic field. The SLR rate constants between spin sublevels exhibit marked anisotropy in their magnitudes and also show appreciable sensitivity to the glycerol content of the aqueous cryogenic matrix. The temperature dependence of SLR suggests that in the temperature range investigated a direct process contributes dominantly to the SLR in this protein. 相似文献
88.
In large multinucleate cells the nuclei enter mitosis and reach metaphase almost synchronously by interaction of the different parts of the cell, but some degrees of postmetaphase asynchrony still persist. Apart from chromosome movements, the important postmetaphase events are re-formation of the nuclear envelope, chromosome decondensation, and back-formation of the spindle. From ultrastructural studies of multinucleate cells showing asynchronous mitotic progression beyond metaphase, we observed that nuclear envelope re-formation takes place nearly synchronously in all chromosome groups as soon as one group has reached telophase and while others are still in earlier mitotic stages. This indicates that nuclear envelope re-formation is an inducible event independent of the degree of condensation or decondensation of the chromatin and may depend on a factor(s) opposite in behavior to the maturation-promoting factor. 相似文献
89.
S K Ghosh 《Steroids》1988,52(1-2):1-14
The development of highly specific monoclonal antibodies to estriol and a nonisotopic immunoassay (EIA) for unconjugated estriol based on the use of these monoclonal antibodies have been described. The monoclonal antibodies show little cross reactivity with other steroids and steroid conjugates and can be used directly in immunoassays without any purification. The EIA described here can be performed in 96-well microtiter plates or polystyrene tubes that have been coated with estriol-bovine serum albumin conjugate. In this assay, estriol in the standard or clinical samples (serum or saliva) competes with the immobilized steroid on the plate or the tube for binding with the antibody. The assay shows good agreement with radioimmunoassay (RIA) and is highly sensitive and reliable. Since no prior processing or extraction of the clinical samples is necessary, the method is potentially applicable for routine use in fetal monitoring as well as in a steroid laboratory. 相似文献
90.
Dilip Ghosh Sumit Bhose R. Manimekalai S. Gowda 《Journal of plant biochemistry and biotechnology.》2013,22(3):343-347
Phytoplasma infected acid lime plants in India develop characteristic symptoms like small chlorotic leaves, multiple sprouting and shortened internodes. Leaves drop prematurely and infected branches have distorted twigs resembling witches’ broom appearance which eventually show die-back symptoms. During its first report in 1999, witches’ broom disease identification was made on the basis of symptomatology and electron microscopy. However, molecular techniques have proved to be more accurate and reliable for phytoplasma detection than the conventional methods. During survey in the year 2010 six samples were collected from infected acid lime plants showing typical field symptoms from Vidarbha region of Maharastra. Initially, phytoplasma bodies were observed in phloem tissues of all six symptomatic samples under JEM 100S transmission electron microscope and all these six samples were subsequently screened using different set of phytoplasma specific universal primers by nested PCR, a widely recommended molecular technique for phytoplasma detection. In the present study P1/P7 “universal” phytoplasma-primer set was used for first round of PCR and amplified products were processed separately for nested PCR with three different nested primer pairs viz. R16F2n/R16R2, R16mF2/R16mR1 and fU5/rU3. The presence of phytoplasma was confirmed in all six suspected samples and one representative ~1.2 kb size amplicon was sequenced and deposited in GenBank as Candidatus Phytoplasma species AL-M (JQ808143). This is the first report of PCR based molecular detection of phytoplasma-induced witches’ broom disease of acid lime (WBDL) in India. Further molecular evaluation to determine the identity to the species level is in progress. 相似文献