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1.
V. Selvakumar P. R. Anbudurai T. Balakumar 《In vitro cellular & developmental biology. Plant》2001,37(2):280-284
Summary A protocol for rapid in vitro propagation using nodal explants obtained from 2-yr-old, field-grown medicinal plants of Plumbago zeylanica L. belonging to the family Plumbaginaceae is described. High frequency bud break and fast development of shoots were induced
on Murashige and Skoog's basal medium supplemented with 27.2 μM adenine sulfate +2.46 μM indole-3-butyric acid (IBA). Induction of rooting was achieved by transferring the shoots to the same basal medium containing
4.92 μM IBA. Using our protocol from one twig of P. zeylanica (eight responsive nodes per explant shoot) within a period of 5 mo., eight plantlets could be raised. After a hardening period
of 4 wk, there was a 90% transplantation success in the field compared to the 60–65% survival of plantlets recorded in the
experiments of previous workers. The plantlets derived through in vitro propagation mimic the growth and morphological characteristics of the donor plants. 相似文献
2.
Deglycosylation studies on tracheal mucin glycoproteins 总被引:4,自引:0,他引:4
H D Woodward N J Ringler R Selvakumar I M Simet V P Bhavanandan E A Davidson 《Biochemistry》1987,26(17):5315-5322
Following several model experiments, conditions were developed for optimal deglycosylation of tracheal mucin glycoproteins. Exposure of rigorously dried material to trifluoromethanesulfonic acid at 0 degree C for up to 8 h results in cleavage of essentially all fucose, galactose, and N-acetylglucosamine, about 80% of the N-acetylneuraminic acid (NeuNAc), and a variable amount of N-acetylgalactosamine (GalNAc), the sugar involved in linkage to protein. Residual N-acetylneuraminic acid is sialidase susceptible and apparently in disaccharide units, presumably NeuNAc2----GalNAc. The remaining N-acetylgalactosamine is mostly present as monosaccharides, and a few Gal beta 1----3GalNAc alpha units are also present; both are cleaved by appropriate enzymatic treatment. The saccharide-free proteins obtained from either human or canine mucin glycoproteins have molecular weights of about 100,000 and require chaotropic agents or detergents for effective solubilization. 相似文献
3.
4.
M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
5.
D Gopal G S Wilson R A Earl M A Cusanovich 《The Journal of biological chemistry》1988,263(24):11652-11656
The ion binding properties of horse, bovine, and tuna cytochrome c (both oxidized and reduced) have been measured using a combination of ultrafiltration, neutron activation, and ion chromatography. The ions investigated were chloride, phosphate, and Tris-cacodylate. Ion chromatography and neutron activation analysis techniques were employed to determine the concentration of free anions. Binding constants are obtained from modified Scatchard plots (in the range of 10-2000 M-1). The redox potentials for cytochrome c at different ionic strengths, pH 7.0, have been determined. In this paper we report the ionic strength and ion binding effects on the redox properties of horse, bovine, and tuna cytochrome c. Potential versus ionic strength dependence for horse, bovine, and tuna cytochrome c from the experimental data were compared with a theoretical model. 相似文献
6.
Summary Lymphocyte karyotyping of an infant girl with the clinical features of microphthalmia, iridoschisis, goiter, hip joint dysplasia, labium synechia and craniotabes revealed an Xp deletion. The lymphocyte karyotypes of the parents were normal. Bromodeoxyuridine incorporation studies showed that, in 42 out of 43 metaphases, the deleted X chromosome was late replicating. In one metaphase, the normal X chromosome was observed to be allocyclic. Using DNA markers from the Xp22 region, the breakpoint was assigned distal to DXS16 (pXUT23) and proximal to DXS143 (dic56). Dosage intensity measurements confirmed that the STS gene and the DNA marker DXS31 were involved in the deleted area. Restriction fragment length polymorphism analysis revealed that the paternally derived X-chromosome was deleted. 相似文献
7.
Tapan K. Ghosh Amita Moitra Gopal K. Kunwar Jyoti S. D. Munshi 《Ichthyological Research》1986,33(3):280-285
Measurements of bimodal oxygen uptake have been made in a freshwater air-breathing fish,Notopterus chitala at 29.0±1(S.D.)°C. xhe mean oxygen uptake from continuously flowing water without any access to air, was found to be 3.58±0.37 (S.E.) ml O2 · h?1 and 56.84+4.29 (S.E.) ml O2 · kg?1 · h?1 for a fish weighing 66.92 + 11.27 (S.E.) g body weight. In still water with access to air, the mean oxygen uptake through the gills were recorded to be 2.49 ± 0.31 (S.E.) ml O2 · h?1 and 38.78 ± 1.92 (S.E.) ml O2 · kg?1 · h?1 and through the accessory respiratory organs (swim-bladder) 6.04±0.87 (S.E.) ml O2 · h?1 and 92.32±2.91 (S.E.) ml O2 · kg?1 · h?1 for a fish averaging 66.92±11.27 (S.E.) g. Out of the total oxygen uptake (131.10 ml O2 · kg?1 · h?1), about 70% was obtained through the aerial route and the remainder 30% through the gills. 相似文献
8.
Summary Groundnut (TMV-2) seeds treated with 25 ppm boron solution germinated more quickly than the seeds supplied with deionized water. The borontreated seedlings also elongated rapidly in the initial phase of the growth even though all their different organs contained excess boron contents (with chlorosis in the leaves) than those of the control seedlings. However, the accentuation in the growth of treated seedlings was proceeded only upto a certain period (12 days after treatment); but further stimulation in the later phase of the growth was almost inhibited with ever increasing amounts of boron in the hypocotyl, plumule and leaves (which were severely chlorotic) and even brought about a deleterious effect on the total growth at the end of 21 days when compared to the controls. 相似文献
9.
Inventory and classification of wetlands in India 总被引:1,自引:0,他引:1
The Indian subcontinent has a large variety of freshwater, saline and marine wetlands. Whereas the mangroves are relatively well documented, very little is known about the other wetlands, with few exceptions. Only recently an inventory of these welands has been prepared but no effort has been made to classify them. A vast majority of the inland wetlands are temporary and/or man-made, and they have been traditionally used and managed by the local human populations. In this paper, first, we evaluate the classification schemes of the IUCN, US Fish and Wildlife Services and those of the Australian wetlands, for their applicability to Indian wetlands. Then, we propose a simple hierarchical classification of wetlands based on their location (coastal or inland), salinity (saline or freshwater), physiognomy (herbaceous or woody), duration of flooding (permanent or seasonal) and the growth forms of the dominant vegetation. We stress upon the hydrological factors which determine all the structural and functional characteristics of the wetlands. We consider that the various growth forms of wetland vegetation integrate the totality of hydrological variables and therefore, can be used as the indicators of different hydrological regimes. 相似文献
10.
Leaf architectural pattern has been studied in 27 genera and 35 species of the Acanthaceae. The major venation pattern conforms
to pinnate camptodromous with eucamptodromous or festooned brochidodromous secondaries, pinnate craspedodromous inAcanthus ilicifolius and acrodromous inLepidagathis trinervis. Intersecondary veins are common. The marginal ultimate venation is looped. The areoles are variable in size. The vein endings
are usually simple, linear or cuved or divide once or twice dichotomously. Isolated vein endings, tracheids, isolated free
vein endings and extension cells are observed. Transfusion tracheids are seen inDicliptera verticillata. Miniature vessel elements with simple perforation plates are noticed lying free in the areole or at the end of tracheids
inSeriocalyx scaber andThunbergia grandiflora.Elytraria acaulis, Nelsonia canescens andStaurogynae zeylanica exhibit venation pattern shown by majority of the taxa studied, of the Acanthaceae. 相似文献