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Siddhartha Kumar Bhaumik Manoj Kumar Singh Subir Karmakar Tripti De 《Glycoconjugate journal》2009,26(6):663-673
As compared to cutaneous leishmaniasis, vaccination against visceral leishmaniasis (VL) has received limited attention. In
this study, we demonstrate for the first time that an UDP-Galactose: N-acetylglucosamine β 1–4 galactosyltransferase (GenBank Accession No. EF159943) expressing attenuated LD clonal population (A-LD) is able to confer protection against the experimental challenge with the virulent LD AG83 parasite. A-LD was also effective in established leishmania infection. The vaccinated animals showed both cell mediated
(in vitro T-cell proliferation, and DTH response) and humoral responses (Th1 type). These results demonstrate the potential of the
attenuated clones as an immunotherapeutic and immunoprophylactic agent against visceral leishmaniasis. 相似文献
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996.
N-caffeoyl-4-amino-n-butyric acid, a new flower-specific metabolite in cultured tobacco cells and tobacco plants 总被引:1,自引:0,他引:1
PUT cells were selected from the XD line of cultured tobacco cells (Nicotiana tabacum L. cv. Xanthi-nc) for the ability to utilize putrescine as sole nitrogen source. Previous work had indicated that hydroxycinnamoylputrescines (principally caffeoylputrescine) and 4-amino-n-butyric acid (GABA) are obligatory intermediates in the assimilation of putrescine by PUT cells. The apparent absence in these cells of diamine or polyamine oxidase and pyrroline dehydrogenase, enzymes which catalyze putrescine oxidation in some plant species, led us to propose the following pathway for putrescine oxidation in PUT cells: putrescine----hydroxycinnamoylputrescine----hydroxycinnamoyl - 4-aminobutyraldehyde----hydroxycinnamoyl-GABA----GABA. We tested the hypothesis by looking for the predicted compound, caffeoyl-GABA. A chemical synthesis was developed, and chromatographic and mass spectroscopic procedures were devised for identifying the compound in extracts of cells and plant tissues. Caffeoyl-GABA was found in extracts of PUT cells in micromolar concentrations but was not present in XD cells. Thus, its occurrence in PUT cells appears to be a direct result of selection for the ability to catabolize putrescine. Caffeoyl-GABA has the same distribution in tobacco plants as caffeoylputrescine, i.e. flower buds greater than open flowers greater than floral leaves, green fruit; absent in vegetative tissues. 相似文献
997.
Energy expenditure was measured during pregnancy in seven primigravid women at 12-15, 25-28, and 34-36 weeks and after the cessation of lactation. On each occasion the resting metabolic rate and the increase in metabolic rate after ingestion of a liquid test meal were measured by indirect calorimetry. In absolute terms the resting metabolic rate increased steadily during pregnancy but when expressed per unit of body weight no change was found. The energetic response to a mixed constituent meal was significantly reduced by 28% in the middle trimester of pregnancy. These findings suggest a possible maternal adaptation to increase energetic efficiency at a time when the energy demands of the fetus are high. 相似文献
998.
P J McLeod 《CMAJ》1987,136(7):709-712
Twelve Canadian medical schools that had an organized faculty development program were surveyed to evaluate the extent to which such programs were used and to estimate their effectiveness. Common practices included sabbaticals and programs designed to improve instructional skills. The main problems included underfunding, poor participation and inadequate instructor evaluation. 相似文献
999.
The myeloarchitectonics of the specific human fields 40, 39, 37c, 37b of neocortex and also fields 17 and 19 which are the cortex end of visual analyzer has been studied with the help of neurohistological and quantitative methods. According to the character of the fibrous bundles, their diameter, the quantity of the fibrous in them and the diameter of the fibrous gradual changes from field 17 to field 19 and further to field 39 have been shown. It is an evidence of the succession between phylogenetically older and younger fields of the cortex. The peculiarities of the field quantitative myeloarchitectonics differing in the function and genesis are marked by heterochronous growth of these fields square in the process of evolution. 相似文献
1000.
A simplified method of manual calculation for inbreeding coefficient (and/or relationship) from complicated pedigree tables presented in a nongraphic mode is offered. The method is based on the use of positional dual codes of ancestors in which all genealogical links of the proband are reflected. 相似文献