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101.
LS Cherkasova GG Vereshchako TM Mironova VA Novik MIu Ta?ts GF Tsykhun VG Fomichenko 《Canadian Metallurgical Quarterly》1977,49(4):15-18
Intensity of glycolysis was studied under conditions of immobilization stress and adrenalectomy as well as with administration of adrenaline and hydrocortisone. The processes of aerobic glycolysis, activity of enzymes of the tricarboxylic acid cycle and mitochondria respiratory chain, content of total, free and protein-bound glycogen, glucose-I-phosphate, glucose-6-phosphate, pyruvate, alpha-ketoglutarate, cytrate and macroergs in the brain are shown to depend on the level of adrenal hormones producing a multilateral effect on a series of energy metabolism links. 相似文献
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Video rate confocal laser scanning microscopy at the highest spatial and temporal resolution of backscattered light (BSL) imaging allowed for regular observation of fast intracellular motion (FIM) first revealed in living neoplastic cells. However, the absence of an objective evaluation has hampered further study of the mechanisms and biological significance of FIM. Particularly, a quantification of apparent differences in velocities that would complement and improve the current demonstration of FIM by color coding using the combination of red-green-blue (RGB) images had been missing. Standard methods of tracking or pattern recognition could not be applied because of the fuzzy nature of images of FIM. A search for a suitable method led to correlation analysis. It was calibrated on Brownian motion and a known type of motion, such as cell marginal ruffling, compared with FIM. Results approved its explanatory potential. Therefore, several crucial incidences of FIM could be analyzed. Apart from an argument against viewing FIM as a manifestation of simple Brownian motion, the correlation analysis of FIM in the adjacent peripheries of a rat fibroblast and a K4 rat sarcoma cell confirmed the notion of higher and uneven distribution of velocity of FIM in a tumor cell so far shown in color-coded images only. This result and other yet unpublished observations indicate that the velocity and topology of FIM can also contribute to a biological distinction between neoplastic and normal cells. Regular application of the correlation analysis should further expand the study of FIM for its mechanisms and predictive value. Such an approach should be thoroughly examined for a contribution to the knowledge of cancer cells. 相似文献
104.
TM Yoshida 《Canadian Metallurgical Quarterly》1999,39(1):65-72; quiz 103-4
OBJECTIVE: To describe assisted reproductive technology (ART) and use of medications during these procedures. DATA SOURCES: Recent clinical literature. STUDY SELECTION: Not applicable. DATA EXTRACTION: Not applicable. DATA SYNTHESIS: ARTs are procedures used in treatment of infertility that involve removal of oocytes and their manipulation outside the woman's uterus. The simplest form of ART, in vitro fertilization, involves aspirating eggs from the ovaries, fertilizing them outside the body, and transferring the embryos into the uterus at the four- to eight-cell stage. Experimental regimens for in vitro fertilization include use of various medications (gonadotropin-releasing hormone agonists, human menotropins, follicle-stimulating hormone, growth hormone) at varying points in the menstrual cycle and after introduction of the embryo into the uterus. Human chorionic gonadotropin has been used to increase implantation of embryos during the woman's luteal phase. Gamete intrafallopian transfer (GIFT) involves transfer of oocytes and sperm into the fallopian tubes, where fertilization takes place. This technique has the advantage of causing the zygote to enter the uterus at the time it would during natural conception. Zygote intrafallopian transfer is similar to GIFT, except that fertilization occurs in vitro, with embryos placed in the fallopian tubes at the two-cell stage. Various micromanipulation techniques and innovative sperm aspiration procedures are currently under development. CONCLUSION: Many advancements have been made in ART, and pharmacists who understand these procedures can serve patients by providing medication information in an empathetic and supportive manner. 相似文献
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Y Luo X Chen TM Downs WC DeWolf MA O'Donnell 《Canadian Metallurgical Quarterly》1999,162(4):2399-2405
Combination therapy with intravesical bacillus Calmette-Guérin (BCG) plus IFN-alpha for superficial bladder cancer has been demonstrated to be more effective than either single agent alone in animal studies and of suggested greater efficacy in clinical studies. However, the mechanism by which IFN-alpha enhances BCG-mediated antitumor activity is poorly understood. Using PBMCs from bladder cancer patients, IFN-alpha was found to substantially enhance the efficacy of BCG to induce IFN-gamma production. Among 34 patients tested, 80% showed >4-fold increase. This effect of IFN-alpha was observed in both initial and memory responses to BCG. In addition, IFN-alpha up-regulated BCG-induced IL-12 and TNF-alpha and down-regulated BCG-induced IL-10. Neutralizing endogenous IL-10 or adding exogenous IL-12 provided further synergy for IFN-gamma production. In clinical practice, intravesical IFN-alpha 2B (50 million units (MU)/dose) was observed to accelerate urinary IFN-gamma production to low-dose BCG (one-tenth or one-third of a full dose) in patients treated with combination therapy compared with BCG alone. These results suggest that IFN-alpha is a potent BCG enhancer that polarizes the BCG-induced immune response toward the cellular immune pathway by promoting Th1 cytokine expression and reducing Th2 cytokine expression. This study provides an immunological basis for future rational use of IFN-alpha in conjunction with intravesical BCG for bladder cancer immunotherapy. 相似文献
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Northern blot analysis revealed that atrial natriuretic peptide (ANP) gene expression occurs in heart, hematocytes and gills of the invertebrate Limulus polyphemus, the horseshoe crab. In low salinity and on land ANP prohormone messenger RNA in Limulus' heart was 32-fold less compared to that in a vertebrate heart (i.e., rat, Rattus norvegicus). ANP gene expression doubled (P < 0.05) in Limulus' heart and gills with change from land and low salinity to medium salinity and osmolality. ANP gene expression was 10-fold higher in Limulus' gills in seawater (i.e., high salinity). The products of this ANP gene expression (i.e., ANP, long acting natriuretic peptide, vessel dilator and kaliuretic peptide) were released and increased in the circulation, i.e., hemolymph, of Limulus proportional to the increase in salinity and osmolality (P = <0.01). These results suggest that modification of ANP gene expression enables animals to adapt to freshwater, seawater, and land. 相似文献
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We have developed a new detection method for measuring distributions of energy depositions from particles characterized by low linear energy transfers (LETs). In particular, we have developed a detection system to measure energy depositions produced by electrons and photons on nanometer scales. The detector is based upon the operational principles of the superheated drop detector (SDD). SDDs consist of tiny droplets of superheated liquid suspended within a gel-like emulsion. The SDDs in this study are fabricated using Freon-115 and a glycerol-based gel as the superheated liquid and host medium. This SDD configuration is operated as a threshold temperature-dependent detector for measuring nanoscopic distributions of energy depositions from low-LET particles. Measured results are compared to the calculated distributions of energy depositions along an electron track. A new electron track code, ESLOW3.1, is used to perform the computational study. Measurements show good agreement with computational results in the energy deposition range of 40-200 eV. 相似文献