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331.
332.
OM Aboul-Dahab MM el-Sherbiny R Abdel-Rahman M Shoeb 《Canadian Metallurgical Quarterly》1994,40(1):653-656
The percentage of gingival tissue and peripheral T, T Subsets and B lymphocytes were assessed in ten pregnant women during the first, second and third trimesters. Clinically the gingival index (GI) was found to be higher during pregnancy than in the control group. The percentage of the T3, T4 and B cells appeared to decrease in peripheral blood and gingival tissues during pregnancy as compared to control group. 相似文献
333.
334.
OM Jolobe 《Canadian Metallurgical Quarterly》1997,349(9054):809-810
335.
OM Za?chenko LM Kyrylova IH Rubezhniak OV Andriienko 《Canadian Metallurgical Quarterly》1997,59(3):33-41
The comparative study of sporulation intensity, change of medium pH, yield of biomass and ethanol soluble fraction (ESF) of extracellular metabolites as well as antibiotic and toxigenic properties of 106 fungi strains which were the potential producers of macrocyclic trichothecenes has been carried out under the conditions of stationary cultivation. It was shown that all the studied Dendrodochium strains were characterized by moderate growth, variations of biomass were within 3.5-4.5 g/l. Variations of ESF level in different strains were rather essential (from 8 to 241.6 mg/l). High antibiotic activity correlated with high or moderate toxicity (on the basis of rabbit skin test) in most cases. Dendrodochium strains with intensive sporulation were as a rule characterized by high efficiency of toxin production (40% of studied strains) and only 3 strains (5.5%) with low level of sporulation were characterized by high rate of toxin production. The toxigenic activity for Myrothecium cinctum, M. commune and M. ukrainicum has been shown for the first time. The toxigenic activity of the studied strains depending on the source of isolation and possible correlative connections between sporulation, toxin formation and other properties are discussed. 相似文献
336.
L Sivaraman LC Stephens BM Markaverich JA Clark S Krnacik OM Conneely BW O'Malley D Medina 《Canadian Metallurgical Quarterly》1998,19(9):1573-1581
One of the most consistent results in the epidemiology of human breast cancer is the inverse relationship of risk and early full-term parity. The goal of this study was to investigate the molecular mechanisms through which early full-term pregnancy protects the breast from cancer development. We used Wistar-Furth (WF) rats as our experimental system and mimicked pregnancy using estrogen and progesterone (E/P). Sexually mature female rats were treated with steroid hormones for 21 days and after 28 days of gland involution, the rats were administered MNU. Rats that received a high dose of 20 microg E and 20 mg P exhibited an 82% reduction in the incidence of mammary adenocarcinomas as compared to the rats receiving only blank pellets. Decreasing doses of E/P were partially protective suggesting that complete differentiation of the gland was not required for refractoriness. We measured the RNA expression levels of several target genes involved in the regulation of mammary cell proliferation and/or differentiation including estrogen receptor (ER) and progesterone receptor (PR), cyclins D1 and D2, the cell cycle inhibitors p16, p21 and p27, and the tumor suppressor p53. At the time of MNU treatment we found no significant differences in the expression of these genes, with the possible exception of p21, indicating that hormone treatment did not result in constitutive changes in expression levels. The numbers of apoptotic cells were low and comparable in the hormone exposed and age-matched virgin gland (AMV) at the time of carcinogen challenge and remained low for 8 days after MNU treatment. The number of BrdU-labeled cells at the time of carcinogen challenge were also low in both the AMV (1.8%) and hormone exposed (0.8%) animals. In contrast, cell proliferation in the AMV (5.7%) was significantly different from both the parous involuted (1.2%) and the E/P-treated involuted (1.5%) animals 8 days after MNU treatment. We interpret these data to indicate that hormone treatment results in mammary epithelial cells that have persistent alterations in intracellular pathways governing proliferation responses to carcinogens. 相似文献
337.
OM Grindel'' IuM Koptelov EL Masherov IN Pronin 《Canadian Metallurgical Quarterly》1998,48(4):671-686
This article discusses the following aspects of the management of the N+ neck: evolution of neck dissection; specificity of staging of the clinically N+ neck; limitations of neck dissection in patients with adverse histologic features; management of bilateral nodal metastases, fixed nodes, and nodes with involvement of skin, nerves or the carotid artery; retropharyngeal nodes; and salvage treatment of the N+ neck following prior irradiation. A summary of the author's own approach is then presented. 相似文献
338.
A 5-month-old female was found with a 16q- trisomy; her mother was the carrier of a balanced translocation 46,XX,t(15p+;16q-)(15p12;16q11). This is the first report in the literature of a liveborn with this chromosome abnormality. 相似文献
339.
Pattern Analysis and Applications - Count data are commonly exploited in machine learning and computer vision applications; however, they often suffer from the well-known curse of dimensionality,... 相似文献