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991.
992.
We describe three lymphoid tumors with the same immunophenotype characteristic for chronic lymphoid leukemia (CD19+/CD5+, clonality of the light immunoglobulin chains, CD23+ and CD10-). However, clinical picture and morphology of neoplastic cells dictate different clinical forms of these cases: chronic lymphoid leukemia, large cell transformation of chronic lymphoid leukemia and diffuse large B-cell lymphoma. Taking into account that immunophenotype reflects the origin of tumor, while clinical outcome and morphological features of cells reflect the stage of tumor progression and/or pathway of tumor formation, we discuss the approach to natural classification of lymphoid tumors based on the process of their evolution. 相似文献
993.
Expression of alcohol dehydrogenase loci was used to estimate hybridity of Lycopersicon esculentum Mill. in 1012 seeds. The banding patterns were obtained by means of vertical block electrophoresis in polyacrylamide gels.
It was established that qualitative variation of locus Adh-2 can be applied to prove hybridity of F1 tomato seeds. This genetic marker is indicative for hybrids with fertile maternal line or with position male sterility line
and not only for maternal line with pollen male sterility.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
Vernigora AN Gengin MT Bardinova ZhS Smetanin VA Petrushova OP 《Ukrainski? biokhimicheski? zhurnal》2003,75(5):99-102
It is revealed, that the activity of neuropeptide metabolism enzymes (carboxypeptidase H, phenylmethylsulfonilfluorid-inhibited carboxypeptidase) in the female rat tissues depends upon the stage of estrus cycle. The carboxypeptidase H activity in the pituitary gland is the highest in proestrus; it is almost 3 times higher in comparison with diestrus; it is a little bit higher in striatum on the stage of estrus, than in diestrus and proestrus, in adrenals on the stage of proestrus and estrus it is a little bit lower, than in diestrus; in the ovaries on the stage of proestrus it is much higher, than in estrus and diestrus. The activity of PMSF-inhibited carboxypeptidase in ovaries on the stage of proestrus and diestrus is 1.7-1.8 times higher, than at the stage of diestrus. The activity of carboxypeptidase M in adrenal tissue at the stage of proestrus is 35-40% of that at the stage of diestrus and estrus. The activity of carboxypeptidase M in the ovaries at the stage of diestrus is 45-50% of that at the stage of diestrus and estrus. The role of the investigated enzymes in cyclic changes of a level of biologically active peptides and in regulation of estrus cycle is discussed. 相似文献
995.
Vasil'eva IS Vaniushkin SA Zinov'eva SV Udalova ZhV Bolychevtseva IuV Paseshnichenko VA 《Prikladnaia biokhimiia i mikrobiologiia》2003,39(6):689-696
Adaptogenic effect of furostanol glycosides (FG) on biosynthesis of photosynthetic pigments in tomato plants (Lycopersicon esculentum Mill.) were studied under conditions of biotic stress caused by root-knot nematode (Meloidogyne incognita Kofoid et White). Treatment of plants with 5 x 10(-4) M FG was accompanied by an increase in the rate of biosynthesis of pigments (particularly, chlorophyll b and carotenoids), which was observed against the background of a decrease in the relative contribution of beta-carotene and an increase in the relative contribution of pigments of violaxanthin cycle (VXC) to the overall pool of carotenoids. It was suggested that FG stimulated phytoimmunity by shifting metabolism of carotenoids toward enhanced biosynthesis of VXC pigments. These pigments play a protective role and facilitate stabilization of photosynthetic apparatus, which is particularly important under stress conditions. 相似文献
996.
The results of studies on the role of plant superoxidesynthase signal system in elicitation of antimicrobial phytoalexin (PA) synthesis in cultured Allium cepa cells are presented. Exogenic application of O2- and H2O2 generators results in formation of PA--Tcibulins 1D and 2 [symbol: see text] in A. cepa cells. The mechanism of PA elicitation does not require peroxidase activity. However, the inhibition of one of the possible sources of the reactive oxygen, HADPH oxidase, suppresses elicitor-stimulated PA production. "Oxidative burst" modulation by different chemical compounds in A. cepa cells results in changes of PA synthesis elicitation. The results obtained suggest the tough correlation between "oxidative burst" and elicitation of defense responses, PA synthesis in particular. 相似文献
997.
Masalimov ZhK Malakhova LV Bruskov VI Bogatova VS Gaziev AI 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2003,43(6):658-661
8-oxoguanine (8-OG) is a biological marker of oxidative damage to DNA by reactive oxygen species. With the help of monoclonal antibodies to 8-OG, by the method of chemiluminescence enzyme immunoassay essential distinctions were found in formation and elimination of this damage to DNA in a liver and brain of mice exposed to 20 Gy of gamma-radiation. A spontaneous level of 8-OG in DNA of brain is much higher than in DNA of liver. Registered immediately after the exposure, the induction of 8-OG in DNA was approximately 3 times greater in brain than in liver. Elimination of 8-OG from DNA of both tissues proceeds more actively only during 30 min after the exposure, and the significant percentage (26-30%) of these damage is kept in DNA of the tissues for 3 hours after the exposure. The levels of lipidsoluble antioxidants, determined by the reaction with a stable free radical, in tissues of mice do not correlate with a quantity of 8-OG, arising in DNA spontaneously and under irradiation. 相似文献
998.
Sereikaitė J. Bassus D. Bobnis R. Dienys G. Bumelienė Zh. Bumelis V.-A. 《Russian Journal of Bioorganic Chemistry》2003,29(3):227-230
The kinetics of the nucleophilic addition reactions of divinyl sulfone to amino groups of glycine and model proteins was studied in aqueous solution at 30°C. The rate constants for glycine, bovine serum albumin, and 1-casein were (4.84 ± 0.58) × 10–1, (2.97 ± 0.31) × 10–2, and (2.38 ± 0.49) × 10–2 M–1 s–1, respectively. Divinyl sulfone was proposed as a crosslinking reagent for the qualitative detection of protein association in solution. The crosslinking capacity of divinyl sulfone was compared to that of 1,3,5-triacryloylhexahydro-s-triazine. 相似文献
999.
Song M Hang TJ Zhang ZhX Du R Chen J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,827(2):205-209
A sensitive and selective LC-MS-MS method has been developed and validated for the determination of cryptotanshinone (CTS) and its active metabolite tanshinone II A (TS II A) in rat plasma using fenofibrate (FOFB) as internal standard. Liquid-liquid extraction was used for sample preparation. Chromatographic separation was achieved on a Waters symmetry ODS column using methanol and water (85:15) as mobile phase delivered at 1.0 mL/min. LC-MS-MS analysis was carried out on a Finnigan LC-TSQ Quantum mass spectrometer using atmospheric pressure chemical ionization (APCI) and positive multiple reaction monitoring. Ions monitored were m/z 297.0--> 251.0 for CTS, m/z 295.0--> 249.0 for TS II A, and m/z 361.1--> 233.0 for FOFB with argon at a pressure of 0.2 Pa and collision energy of 25 eV for collision-induced dissociation (CID). The assay was linear over the range 0.1-20 ng/mL for CTS and 0.2-15 ng/mL for TS II A. The average recoveries of CTS and TS II A from rat plasma were 93.7 and 94.7%, respectively. The established method has been applied in a pharmacokinetic study of CTS in rats. 相似文献
1000.