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61.
Cluster Computing - Cognitive Radio Network is an emerging popular wireless network, designed for efficient spectrum utilization. It enables unlicensed users to access the unused portion of the... 相似文献
62.
Sindhu Meenakshi Kumar Anil Yadav Honey Chaudhary Darshna Jaiwal Ranjana Jaiwal Pawan K. 《Plant Cell, Tissue and Organ Culture》2019,139(3):429-453
Plant Cell, Tissue and Organ Culture (PCTOC) - Cowpea (Vigna unguiculata (L.) Walp.) is a warm-season legume crop which is widely grown by resource-poor small and marginal farmers of Sub-Saharan... 相似文献
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Neosporosis 总被引:6,自引:0,他引:6
Neospora caninum is a recently recognized protozoan parasite of animals, which, until 1988, was misdiagnosed as Toxoplasma gondii. Neospora caninum or Neospora-like parasites, here discussed by J.P. Dubey and David Lindsay, cause paralysis and death in dogs and neonatal mortality and abortion in cattle, sheep, goats and horses. 相似文献
66.
Sirakova TD Thirumala AK Dubey VS Sprecher H Kolattukudy PE 《The Journal of biological chemistry》2001,276(20):16833-16839
Multidrug-resistant tuberculosis is a major global health emergency. Cell wall lipids of Mycobacterium tuberculosis can play crucial roles in the pathogenesis. The enzymes involved in their synthesis can be ideal new drug targets against tuberculosis, because many such lipids are unique to this pathogen. A variety of multiple methyl-branched fatty acids are among such unique lipids. We have identified seven genes highly homologous to the mas gene, which is known to be involved in the production of one class of such multiple methyl-branched fatty acids. One of these mas-like genes, pks2, was disrupted using a phage-mediated delivery of the disruption construct. Gene disruption by homologous recombination was confirmed by polymerase chain reaction analysis of the flanking regions of the introduced disrupted gene and by Southern analysis. Thin-layer and radio gas-chromatographic analyses of lipids derived from [1-14C]propionic acid and gas chromatography/mass spectrometry analysis of the fatty acids and hydroxy fatty acids showed that the pks2 mutant was incapable of producing hepta- and octamethyl phthioceranic acids and hydroxyphthioceranic acids that are the major acyl constituents of sulfolipids. Consequently, pks2 mutant does not produce sulfolipids. Sulfolipid deficiency in pks2 mutant was confirmed by two-dimensional thin-layer chromatographic analysis of lipids derived from [1-14C]propionic acid and 35SO4(-2). With this sulfolipid-deficient mutant, it should be possible to test for the postulated important roles for sulfolipids in the pathogenesis of M. tuberculosis. 相似文献
67.
Dubey JP Liddell S Mattson D Speert CA Howe DK Jenkins MC 《The Journal of parasitology》2001,87(2):345-353
Neospora hughesi was isolated in cell cultures inoculated with homogenate of spinal cord from a horse in Oregon. Tachyzoites of this Oregon isolate of N. hughesi were maintained continuously by cell culture passage and tachyzoites were infective to immunosuppressed mice. Gamma interferon gene knockout (KO) mice injected with tachyzoites developed fatal myocarditis and numerous tachyzoites were seen in lesions. Gerbils (Meriones unguiculatus) inoculated with tachyzoites developed antibodies (> or = 1:500) as indicated by the Neospora caninum agglutination test but did not develop clinical signs, and Neospora organisms were not demonstrable in their tissues. Tissue cysts were not found in gerbils, nude mice, KO mice, immunosuppressed outbred Swiss Webster mice, or BALB/c mice injected with the Oregon isolate of N. hughesi. Ultrastructurally, tachyzoites of the Oregon isolate from the myocardium of infected KO mice and from cell culture were similar to N. caninum tachyzoites. Western blot analysis using NcSAG1 and NcSRS2 polyclonal and monoclonal antibodies and characterization of the internal transcribed spacer 1 sequences from the equine isolates and different isolates of N. caninum from dogs and cattle indicated that the Oregon isolate of N. hughesi is distinct from N. caninum isolates from cattle and dogs. 相似文献
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Prevalence of antibodies to Toxoplasma gondii was determined in 147 barren-ground caribou (Rangifer tarandus groenlandicus) from 5 herds in the Northwest Territories and Nunavut, northern Canada, by the modified agglutination test (MAT). In the mainland herds (Bluenose, Bathurst, and Beverly), antibodies were found in 43 (37%) of 117 caribou, and MAT titers were 1:25 in 10, 1:50 in 24, and 1:500 in 9. In the island herds, only 1 (4.3%) of 23 animals sampled from the North Baffin Island herd was positive (titer = 1:25) and no antibodies were detected in 7 caribou from the Dolphin and Union herd. The high prevalence of antibodies to T. gondii in the mainland caribou herds indicates that caribou meat may contain viable T. gondii. 相似文献
69.
Singh Anjana Pandey K.D. Dubey R.S. 《World journal of microbiology & biotechnology》1999,15(2):277-282
Reverse micelles serve as a novel tool to entrap enzymes and microbial whole cells within aqueous pockets and can be of great use in enhancing the efficiency and sustainability of the biological system. Photosynthetic bacterium Rhodopseudomonas sphaeroides entrapped inside the aqueous pool of reverse micelles prepared from benzene-sodium lauryl sulphate exhibited 25-fold enhancement of H2 photoproduction rate (1.67 ml H2 [mg protein]–1 h–1) compared to cells suspended in normal aqueous medium. Hydrogen photoproduction by the bacterium was catalysed by the nitrogenase enzyme system which was supported at a low light intensity of 12 Em–2 sec–1 photon flux energy at a wavelength of 520 nm. The optimum temperature for the process was 40 °C. 相似文献
70.
Serum samples of domestic pigs (Sus scrofa), elands (Taurotragus oryx), sable antelopes (Hippotragus niger), warthogs (Phacochoerus aethiopicus), bushpigs (Koiropotamus [Potamochoerus] koiropotamus), white rhinos (Ceratotherium simus), African buffalos (Syncerus caffer), wildebeest (Connochaetas taurinus), and African elephants (Loxodonta africana) from Zimbabwe were tested for Toxoplasma gondii IgG antibodies by the modified agglutination test (MAT) with whole formalized tachyzoites and mercaptoethanol. Sera were diluted at 1:25, 1:50, and 1:500 for MAT testing. Sera with antibodies in a 1:25 dilution were considered to have T. gondii infection. Toxoplasma gondii antibodies were found in 9.3% of 97 domestic pigs, 36.8% of 19 elands, 11.9% of 67 sables, 0 of 3 warthogs, 0 of 3 bushpigs, 50% of 2 white rhinos, 5.6% of 18 buffalos, 14.5% of 69 wildebeest, and 10.5% of 19 elephants examined. 相似文献