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Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
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Sabri Acarturk Emrah Arslan Ferit Demirkan Sakir Unal 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(4):409-16; discussion 417-8
Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed. 相似文献
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Neurons are terminally post-mitotic cells that utilize their microrubule arrays for the growth and maintenance of axons and dendrites rather than for the formation of mitotic spindles. Recent studies from our laboratory suggest that the mechanisms that organize the axonal and dendritic microtubule arrays may be variations on the same mechanisms that organize the mitotic spindle in dividing cells. In particular, we have identified molecular motor proteins that serve analogous functions in the establishment of these seemingly very different microtubule arrays. In the present study, we have sought to determine whether a non-motor protein termed NuMA is also a component of both systems. NuMA is a ~230 kDa structural protein that is present exclusively in the nucleus during interphase. During mitosis, NuMA forms aggregates that interact with microtubules and certain motor proteins. As a result of these interactions, NuMA is thought to draw together the minus-ends of microtubules, thereby helping to organize them into a bipolar spindle. In contrast to mitotic cells, post-mitotic neurons display NuMA both in the nucleus and in the cytoplasm. NuMA appears as multiple small particles within the somatodendritic compartment of the neuron, where its levels increase during early dendritic differentation. A partial but not complete colocalization with minus-ends of microtubules is suggested by the distribution of the particles during development and during drug treatments that alter the microtubule array. These observations provide an initial set of clues regarding a potentially important function of NuMA in the organization of microtubules within the somatodendritic compartment of the neuron. 相似文献
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Our objective was to compare the relationship between age, basal follicle stimulating hormone (FSH) level and ultrasound-measured mean ovarian volume (MOV) and mean antral follicle counts (MFC) in a group of infertile and fertile women between the ages of 35 and 45 years. Menstrual cycle day 3 serum FSH, MOV and MFC were analyzed in 62 infertile and 53 fertile women. Basal FSH and MFC did not differ between infertile and fertile women, whereas MOV was significantly smaller in infertile women (p < 0.05). In the infertile group, there was a negative correlation between MOV and age (rho = -0.389, p < 0.05), between MOV and basal FSH (rho = 0.495, p < 0.01), and between MFC and age (rho = -0.553, p < 0.01). In the fertile group, there was a strong negative correlation between MOV and basal FSH (rho = -0.631, p < 0.01), and between MFC and basal FSH (rho = -0.710, p < 0.01). Mean basal FSH, MOV and MFC did not differ between subgroups of patients with different causes of infertility. In the infertile group, patients with small ovaries of volume less than 1.8 cm(3) (mean volume -1 SD) had higher mean basal FSH (p < 0.05) and lower MFC (p < 0.01) levels than patients with normal ovarian volume. In conclusion, transvaginal ultrasound (TVU) indices and indirect hormonal parameters of ovarian reserve were similar in infertile and fertile women aged between 35 and 45 years. It is suggested that, in infertile women above 35 years of age, TVU rather than hormonal parameters be preferred, based on our data showing a stronger association between age and TVU indices of ovarian reserve than between age and increase in basal FSH level. Thus, TVU assessment of ovarian volume and antral follicle counts is a practical and cost-effective, if not better, technique for ovarian reserve testing. 相似文献
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The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report 总被引:1,自引:1,他引:0
Arslan N Ozturk E Ilgan S Narin Y Dundar S Tufan T Pekcan M Bayhan H 《Annals of nuclear medicine》2000,14(1):39-46
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI. 相似文献