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101.
The changes of bioelectric activity of the brain hemispheres were studied under the influence of an alternating magnetic field (AMF), directed on the hand of 20 epileptic patients and 18 healthy normals. Under AMF influence there was intensification of epileptic activity--elevation of the focal bioelectric characteristics and of the processes of generalization. It permitted to apply AMF for diagnosis of epileptic focus. Under AMF influence more stable changes in posterio-parietal areas of the right hemisphere occur. The authors came to the conclusion that AMF effects were mainly realized with participation of right hemisphere. 相似文献
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An immune complex selective affinity column utilizing site-specific attachment of bovine conglutinin
Established leukemic cell lines have been useful models for studying the biology of leukemia. Analysis of the actions of differentiating agents on leukemic cell lines in vivo has been limited by an inability to unambiguously distinguish host hematopoietic elements from differentiated leukemic cells. In order to identify and quantify leukemic cells during in vivo studies, a derivative of the murine myelomonocytic leukemia cell line WEHI-3B D+, which stably expresses beta-galactosidase, was constructed utilizing retroviral vector gene transfer. This cell line, termed WEHI-3B D+/lacZ 2.8, demonstrated in vitro growth and differentiation properties similar to the parental cell line. WEHI-3B D+/lacZ 2.8 expressed high levels of beta-galactosidase following prolonged in vitro growth and following differentiation in suspension cultures and clonogenic assays. In vivo, WEHI-3B D+/lacZ 2.8 was leukemogenic and high level expression of beta-galactosidase was maintained. Quantification of tissue involvement with WEHI-3B D+/lacZ 2.8 leukemia was performed utilizing staining with the fluorogenic beta-galactosidase substrate fluorescein di-beta-galactoside and fluorescence-activated cell sorting analysis. In vivo differentiation efficiency following granulocyte colony-stimulating factor (G-CSF) administration was determined using a simultaneous nuclear and cytoplasmic staining procedure. Results indicate that treatment of mice inoculated with WEHI-3B D+/lacZ 2.8 cells with G-CSF administration causes detectable but limited differentiation. 相似文献
104.
AB Abou-Samra H Jüppner A Khalifa H Karga XF Kong D Schiffer-Alberts LY Xie GV Segre 《Canadian Metallurgical Quarterly》1993,132(2):801-805
Complementary DNA encoding a rat bone PTH/PTHrP receptor was stably expressed in the murine corticotroph cell line, AtT-20. Several clones, expressing variable numbers of PTH/PTHrP receptors, were developed. In contrast to the relatively low binding affinity (apparent Kd = 15 nM) observed in COS-7 cells transiently expressing the PTH/PTHrP receptor, all AtT-20 stable transfectants bound [Nle8,18,Tyr34]bPTH(1-34)NH2 (NlePTH) with an affinity that was indistinguishable from that observed in ROS 17/2.8 cells expressing native PTH/PTHrP receptors. Additionally, NlePTH dramatically increased cAMP accumulation and ACTH release in AtT-20 cells expressing the PTH/PTHrP receptor with an ED50 of 0.6 +/- 0.3 and 0.3 +/- 0.1 nM, respectively. The high binding affinity and the high efficacy of NlePTH in stimulating cAMP accumulation and ACTH release indicate that the PTH/PTHrP receptor is efficiently coupled to the intracellular signalling system responsible for stimulation of ACTH release in AtT-20 cells. No additivity of cAMP accumulation or of ACTH release was observed when these cells were treated with maximally active concentrations of both NlePTH and CRF. This suggests that the receptors for both of these hormones share the same intracellular effectors, and that intracellular signaling in AtT-20 cells is not compartmentalized. Additionally, the ability of NlePTH to stimulate ACTH release in AtT-20 cells, a function that is normally performed by CRF, demonstrates promiscuity between activated receptors and distal biological functions. 相似文献
105.
VA Nikolaev AN Surovaia NIu Sidorova SL Grokhovski? AS Zasedatelev GV Gurski? AL Zhuze 《Canadian Metallurgical Quarterly》1993,27(1):192-210
An analogue of netropsin has been synthesized consisting of two N-propylpyrrolcarboxamide units linked covalently to a copper-chelating tripeptide Gly-Gly-L-His by means of two and three glycine residues. Binding to DNA and synthetic polynucleotides of netropsin analogue containing three glycine residues between Gly-Gly-L-His tripeptide and the N-end of netropsin analogue (His-Nt) has been studied. It is shown that this netropsin analogue chelates a copper ion with 1:1 stoichiometry, similar to a free Gly-Gly-L-His peptide. It is found that this netropsin analogue occupies 3 to 4 base pairs upon binding to poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers, irrespective of whether it binds in Cu(2+)-ligated or unligated forms. Binding constants and binding site sizes have been calculated for netropsin analogue complexes with DNA, poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers at the [Cu2+]/[His-Nt] ratio equal to 0 and 1.0. In the three-component system including His-Nt and Cu(2+)-His-Nt, cooperative effects are recognized which can be explained by heterodimer generation on interaction of His-Nt and Cu(2+)-His-Nt at adjacent binding sites. 相似文献
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GV Seledtsova VI Seledtsov DM Samarin VIa Taraban SV Sennikov EA Kashchenko VA Kozlov 《Canadian Metallurgical Quarterly》1997,124(11):550-553
The bio-psycho-social model was used in the presented study to observe the course of chronic diseases. An attempt was undertaken to correlate the psychosocial situation of 165 women with no presence of disease following breast cancer or genital cancer with their present organic status. The open discussion, a half standardized interview and the gynecological-oncological physical examination were implemented using predetermined parameters. The results of the general well-being scores from the interview and the results of organic status for all 165 patients were related using a rank-correlation between the objective and subjective score. A discrepancy between the psychosocial situation and the objective physical finding was found in the majority of women. The goal of the treatment of chronically ill patients especially following oncological tumors should thus have equal emphasis on the psychosocial and organic dimensions of the disease. 相似文献
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K Triantafyllou GV Papatheodoridis GA Paspatis TH Vasilakaki I Elemenoglou DG Karamanolis 《Canadian Metallurgical Quarterly》1997,44(14):533-538
BACKGROUND/AIMS: In order to reduce the number of colonoscopies performed for the surveillance of patients after polypectomy, suitable predictors of adenomas recurrence are needed. The aim of this study was to find predictors of the early development of metachronous adenomas and specifically of advanced ones. MATERIALS AND METHODS: Forty-four patients underwent total colonoscopy 24-26 months after initial endoscopic polypectomy. All polyps were endoscopically removed and an adenoma was considered as advanced if the diameter was > 1 cm and/or villous component and/or severe dysplasia were present. RESULTS: Metachronous adenomas were detected in 16 (36.4% patients. Five (11.4%) of them had advanced metachronous adenomas. Early recurrence of adenomas was significantly correlated with the total number of indices adenomas (p = 0.027). On the contrary, the presence of metachronous adenomas was not related to any of the patients' characteristics nor to the site and the histology of the indices adenomas. The development of advanced metachronous adenomas during the same period was significantly correlated with patients' age, as it was observed only in patients aged > or = 60 years (5/21 or 23.8%) and in none of the patients aged < 60 years (Odds ratio: 15.7, p = 0.02). Logistic regression analysis revealed that patient's age was the only significant predictor of the early development of advanced metachronous adenomas (beta = 0.40, p = 0.02) and that the number of the indices adenomas was the only significant predictor for the recurrence of all adenomas (beta = 1.59, p = 0.02). CONCLUSIONS: 1. Only patients aged > or = 60 years seem to develop advanced metachronous adenomas two years after polypectomy and 2. The likelihood for developing metachronous adenomas during the same period is related to the number of indices adenomas. 相似文献