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41.
J Nikolakopoulos C Zachariah D Mota de Freitas EB Stubbs R Ramasamy MC Castro CF Geraldes 《Canadian Metallurgical Quarterly》1998,71(4):1676-1684
Lithium has been used clinically in the treatment of manic depression. However, its pharmacologic mode of action remains unclear. Characteristics of Li+ interactions in red blood cells (RBCs) have been identified. We investigated Li+ interactions on human neuroblastoma SH-SY5Y cells by developing a novel 7Li NMR method that provided a clear estimation of the intra- and extracellular amounts of Li+ in the presence of the shift reagent thulium-1,4,7,10-tetrazacyclododecane-N,N',N',N'-tetramethylene phosphonate (HTmDOTP4-). The first-order rate constants of Li+ influx and efflux for perfused, agarose-embedded SH-SY5Y cells in the presence of 3 mM HTmDOTP4- were 0.055 +/- 0.006 (n = 4) and -0.025 +/- 0.006 min(-1) (n = 3), respectively. Significant increases in the rate constants of Li+ influx and efflux in the presence of 0.05 mM veratridine indicated the presence of Na+ channel-mediated Li+ transport in SH-SY5Y cells. 7Li NMR relaxation measurements showed that Li+ is immobilized more in human neuroblastoma SH-SY5Y cells than in human RBCs. 相似文献
42.
Assessment of gestational age is one of the most important aims of ultrasonography in obstetrics. As pregnancy progresses, influences of factors which makes the growth of the fetuses different, cumulates. It has been revealed that the earlier in pregnancy ultrasound examination was performed, the better precision in the assessment of gestational age was obtained. The best precision is encountered when Crown-rump length is measured between 7-9 weeks of gestation. Until the end of the half of pregnancy, biparietal measurement allows for better assessment of gestational age than the date of the last menstrual period. As pregnancy progresses the variability of the measurements increases, reaching 7 week variation at term. The aim of this study is the assessment of fetal sacral length ultrasonographic measurements in the calculation of gestational age. The investigated group consists of 453 pregnant women between 16-41 weeks of physiological gestation. 相似文献
43.
EB Nikol'skaia OV Iagodina BA Grinberg MM Dianova 《Canadian Metallurgical Quarterly》1998,70(3):50-56
Isolation of highly purified and highly molecular monoamine oxidase (MAO) from pig liver mitochondria have been worked out. Specific activity of isolated preparation is 2700 times higher than of original mitochondria homogenate. Enzyme solubilization by digitonin, affinity chromatography purification and ultrafiltration underlie this method. MAO catalytic properties changing during the process of purification by different methods have been investigated. Substrate specificity was studied; kinetic parameters of enzymatic desemination were calculated. 相似文献
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WC Buijs JG Tibben OC Boerman CF Molthoff LF Massuger EB Koenders CP Schijf JA Siegel FH Corstens 《Canadian Metallurgical Quarterly》1998,25(11):1552-1561
In this study the potential of intraperitoneal (i.p.) and intravenous (i.v.) administration of chimeric iodine-131-labelled MOv18 IgG for radioimmunotherapy was determined. The dosimetry associated with both routes of administration of cMOv18 IgG was studied in patients. Eight patients suspected of having ovarian carcinoma received 150 MBq 131I-cMOv18 IgG i.p. Blood and urine were collected and serial gamma camera images were acquired. Another group of four patients received 7.5 MBq 131I-cMOv18 IgG i.v. For all patients, tissue biopsies were obtained at surgery. Activity in the blood after i.p. administration was described by a bi-exponential curve with a mean uptake and elimination half-life of 6.9+/-3.2 h and 160+/-45 h, respectively. For i.v. infusion the mean half-life for the elimination phase was 103+/-12 h. Cumulative excretion in the urine was 17%+/-3% ID and 21%+/-7% ID in 96 h for i.p. and i.v. administration, respectively. Scintigraphic images after i.p. administration showed accumulation in ovarian cancer lesions, while all other tissues showed decreasing activity with time. Tumour uptake determined in the ovarian cancer tissue specimens ranged from 3.4% to 12.3% ID/kg for i.p. administration and from 3.6% to 5.4% ID/kg for i.v. administration. Dosimetric analysis of the data indicated that 1.7-4.3 mGy/MBq and 1.7-2.2 mGy/MBq can be guided to solid or ascites cells after i.p. and i.v. administration, respectively. Assuming that an absorbed dose to the bone marrow of 2 Gy will be dose limiting, a total activity of 4.1 GBq 131I-cMOv18 IgG can be administered safely via the i.p. route and 3.5 GBq via the i.v. route. At this maximal tolerated dose, a maximum absorbed dose to 1-g tumours in the peritoneal cavity of 18 and 8 Gy can be reached after i.p. and i.v. administration, respectively. For the i. p. route of administration, dose estimates for the tumour are even higher when the electron dose of the peritoneal activity is also taken into account: total doses to the tumour of 30 Gy and 22 Gy will be absorbed at the tumour surface and at 0.2 mm depth, respectively. In conclusion, therapeutic tumour doses can be achieved with 131I-cMOv18 IgG in patients with intraperitoneal ovarian cancer lesions with no normal organ toxicity. The i.p. route of administration seems to be preferable to i.v. administration. 相似文献
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48.
JM Paramio S Laín C Segrelles EB Lane JL Jorcano 《Canadian Metallurgical Quarterly》1998,17(8):949-957
Terminal differentiation requires cell cycle withdrawal, suggesting the involvement of negative cell cycle controllers in the process. We have analysed the involvement of the retinoblastoma family of proteins (pRb, p107 and p130) in epidermal proliferation and differentiation. These proteins play key roles as inhibitors of cell cycle progression and are involved in muscle and neuron differentiation. We found that during in vitro differentiation of human HaCaT keratinocytes, pRb, p107 and p130 are sequentially expressed, in contrast to the co-expression observed during cell cycle progression in the same cells. Immunofluorescence studies on skin sections revealed the presence of pRb and p107 in basal and suprabasal cell layers, whilst p130 is restricted to cells already committed to differentiation in the suprabasal compartments. To explore the functional significance of the differential expression of these proteins, transfection experiments were performed in HaCaT keratinocytes. We observed that the forced over-expression of pRb, p107 or p130 individually did not induce differentiation of the transfected cells. However, the co-transfection of pRb and p107 induced the expression of early differentiation markers (keratin k10) and triple transfectants pRb+p107+p130 expressed markers representative of later stages of epidermal differentiation (involucrin). Finally, we observed that these three proteins repress keratinocyte proliferation, although to a different extent (p107>pRb> or =p130). These results indicate that the members of the pRb family play specific, yet coordinated roles during epidermal differentiation, and that the ordered progression along the different stages of this process results from the effects of different combinations of these proteins. 相似文献
49.
Karyotypes were prepared from peripheral blood leukocytes in 77 couples in whom there was no apparent cause for recurrent spontaneous abortion. In addition to conventional staining, chromosomes were stained by the new technics for Q-, G-, or C-banding. Translocations were found in 5 of 154 persons (3.25% or 1:31 individuals). The frequency of translocations in the general adult population is 0.4% (1:255). Two translocations were apparent only with the new technics for banding. The incidence of chromosomal microanomalies was 7.79% (2.6% in the general population). Karyotyping of couples with recurrent abortion is recommended, with use of the new staining technics. 相似文献
50.