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61.
Chereshnev VA Iushkov BG Sumin MN Tiumentseva NV Khramtsova IuS Danilova IG 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2004,90(10):1193-1202
The formation of blood system adoptive reaction in many cases is defined by the type of action and the condition of hemopoietic inductive microenvironment: hemodynamics of hemopoietic tissue, functional conditions of bone marrow macrophages, mast cells and glycosaminoglycans content. The shift in hemodlobin fraction occurs in extreme conditions requiring an increased gas transport by the blood. In case of tissue lesion, lymphocytes stimulate their regeneration. Morphogenetic function of lymphoid cells may be alerted by immunomodulators. Blood cells participate in angiogenesis, and this property may be used for vessel grafts production. 相似文献
62.
Phenotypic and genotypic characteristics and epidemiological significance of ctx+ strains of Vibrio cholerae isolated from seafood in Malaysia 总被引:2,自引:0,他引:2
Chen CH Shimada T Elhadi N Radu S Nishibuchi M 《Applied and environmental microbiology》2004,70(4):1964-1972
Of 97 strains of Vibrio cholerae isolated from various seafoods in Malaysia in 1998 and 1999, 20 strains carried the ctx gene and produced cholera toxin. Fourteen, one, and five of these toxigenic strains belonged to the O139, O1 Ogawa, and rough serotypes, respectively. The rough strains had the rfb gene of the O1 serotype. The toxigenic strains varied in their biochemical characteristics, the amount of cholera toxin produced, their antibiograms, and the presence or absence of the pTLC plasmid sequence. DNA fingerprinting analysis by arbitrarily primed PCR, ribotyping, and a pulsed-field gel electrophoresis method classified the toxigenic strains into 3, 7, and 10 types, respectively. The relatedness of these toxigenic strains to clinical strains isolated in other countries and from international travelers was examined by using a dendrogram constructed from the pulsed-field gel electrophoresis profiles. The results of the examination of the antibiogram and the possession of the toxin-linked cryptic plasmid were consistent with the dendrogram-based relatedness: the O139 strains isolated from Malaysian seafoods could be separated into two groups that appear to have been introduced from the Bengal area independently. The rough strains of Malaysian seafood origin formed one group and belonged to a cluster unique to the Thailand-Malaysia-Laos region, and this group may have persisted in this area for a long period. The single O1 Ogawa strain detected in Malaysian seafood appears to have an origin and route of introduction different from those of the O139 and the rough strains. 相似文献
63.
Paraquat resistance of transgenic tobacco plants over-expressing the Ochrobactrum anthropi
pqrA gene
Transgenic tobacco plants over-expressing the Ochrobactrum anthropi pqrA gene, which encodes a membrane transporter mediating resistance to paraquat, were generated. Transgenic plants displayed higher resistance against paraquat than wild-type plants, as estimated by plant viability, ion leakage and chlorophyll loss, but no resistance against other active oxygen generators, such as H2O2 and menadione. Moreover, lower levels of paraquat accumulated in transgenic plants, compared to wild-type plants, indicating that the PqrA protein detoxifies paraquat either via increased efflux or decreased uptake of the herbicide, but not by removing active oxygen species. The results collectively demonstrate that the bacterial paraquat resistance gene, pqrA, can be functionally expressed in plant cells, and utilized for the development of paraquat-resistant crop plants. 相似文献
64.
Ultrafine oxidized cellulose (OC) mats were prepared by oxidation of ultrafine cellulose mats produced by electrospinning and subsequent deacetylation of cellulose acetate for potential applications in nonwoven adhesion barriers. When ultrafine cellulose mats were oxidized with a mixture of HNO3/H3PO4 - NaNO2 (2/1/1.4 v/v/wt %), their ultrafine mat structure remained unchanged. The yield and carboxyl content of OC mats were 86.7% and 16.8%, respectively. OC showed lower crystallinity than cellulose because the oxidation of cellulose proceeded via disruption of hydrogen bonds between cellulose chains. The swelling behaviors of ultrafine OC mats were dependent on the type of swelling solution. In a physiological salt solution, their degree of swelling was approximately 230%. 相似文献
65.
Purification and cDNA cloning of a cecropin-like peptide from the great wax moth, Galleria mellonella 总被引:4,自引:0,他引:4
A cecropin-like antimicrobial peptide, Gm cecropin, was purified from hemolymph of larvae of the wax moth, Galleria mellonella, immunized against E. coli, and its antibacterial activity was examined in a radial diffusion assay. The molecular mass of Gm cecropin was 4,160.69 Da by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry analysis. The full-length cDNA of the Gm cecropin precursor was cloned by a combination of RT-PCR, based on the N-terminal sequence obtained by Edman degradation, and 5'-RACE-PCR. Analysis of the cDNA showed that cecropin is synthesized as a prepropeptide, with a putative 22-residue signal peptide, a 4-residue propeptide and a 39-residue mature peptide with a calculated mass of 4,344.18 Da the difference between the calculated and measured masses suggests that Gm cecropin is a 37-residue peptide generated by removal of the C-terminal residue and amidation. 相似文献
66.
We report a prenatally diagnosed balanced de novo translocation t(6;7)(p25;q31). Physical examination of the baby born at term revealed only a posterior cleft palate. Laboratory examinations and radiologic investigations were found normal. Two years follow-up of the patient showed her mental and motor development was appropriate with her age. Our report is the first observation on balanced de novo translocation t(6;7)(p25;q31) and cleft palate. Association of this translocation and cleft palate has not been reported previously. 相似文献
67.
Excessive breakdown of extracellular matrix by metalloproteinases (MMPs) occurs in many pathological conditions. Consequently, methods for inhibiting MMP activity have therapeutic potential. In this study, we investigated the effect of G-120, a 120 kDa glycoprotein purified from the Oriental herbal plant, Ulmus davidiana Nakai (UDN), on the activity and production of several MMPs by evaluating its growth inhibitory effect on NIH 3T3 cells. Tritium uptake assays showed that proliferation of NIH 3T3 cells was strongly suppressed, and G-120-mediated inhibition of DNA synthesis proved to involve a cytostatic, rather than a cytotoxic, effect, as shown by cytotoxicity and apoptosis assays. More importantly, G-120 strongly reduced the gelatinolytic and collagenase activities of MMP proteins, as well as expression of MMP-2 and MMP-9. Electrophoretic mobility shift assays revealed that it suppressed the DNA binding activity of NF-kappaB. Collectively, our observations show that G-120 strongly inhibits the activation of MMPs and NF-kappaB. 相似文献
68.
Lee SH Lee MY Kang HM Han DC Son KH Yang DC Sung ND Lee CW Kim HM Kwon BM 《Bioorganic & medicinal chemistry》2003,11(21):4545-4549
Members of the Artemisia genus are important medicinal plants found throughout the world. Arteminolides A-D (1-4), isolated from the aerial parts of Artemisia, have an inhibitory activity on farnesyl-protein transferase (FPTase; EC 2.5.1.29) in in vitro assay. This study was carried out with the purpose of validating anti-tumor effects of the compounds in human tumor cells and mouse xenograft model. The arteminolides inhibited tumor cell growth in a dose-dependent manner. Furthermore, arteminolide C (3) blocked in vivo growth of human colon and lung tumor xenograft without the loss of body weight in nude mice. 相似文献
69.
Lee CK Lee CU Kim JH Son BC Kim DH Lee CH Kim HD Kim JW Yoon YD Kang SG Moon DH 《Molecules and cells》2003,15(1):114-121
This study was performed to investigate the effects of Aroclor 1254 (A1254), a commercial polychlorinated biphenyl mixture, on the expression of rat placental prolactin (PRL) family genes and reproductive activity. Placental lactogen-Iv and -II, and prolactin-like protein-A and -C mRNA levels were significantly decreased in the placentas of A1254-treated rats in a dose-dependent manner. The mRNA levels of Pit-1alpha and beta isotypes, which are involved in the regulation of PRL family gene expression, were also decreased in the A1254-treated rat placenta. In the rat placental junctional zone, high-dose A1254 (25 mg/kg B.W.) treatment reduced the number of spongiotrophoblasts, cells in which the PRL family genes are expressed. Finally, maternal exposure to A1254 was shown to have significant toxic effects on reproductive activity, including embryonic and placental growth retardation, delay of parturition, and reduction of the number of pups per litter. The results of the present study indicated that A1254 has an inhibitory effect on PRL family, Pit-1alpha, and beta gene expression in the rat placenta, leading to significant toxic effects on reproductive activity in rats. 相似文献
70.