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排序方式: 共有620条查询结果,搜索用时 15 毫秒
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Roni T. Falk JoAnn E. Manson Vanessa M. Barnabei Garnet L. Anderson Louise A. Brinton Thomas E. Rohan Jane A. Cauley Chu Chen Sally B. Coburn Ruth M. Pfeiffer Kerryn W. Reding Gloria E. Sarto Nicolas Wentzensen Rowan T. Chlebowski Xia Xu Britton Trabert 《International journal of cancer. Journal international du cancer》2019,144(4):730-740
The WHI found an unexpected reduced breast cancer risk in women using CEE alone. We hypothesized CEE alone induces estrogen hydroxylation along the 2-pathway rather than the competing 16-pathway, a pattern linked to reduced postmenopausal breast cancer risk. One thousand eight hundred and sixty-four women in a WHIOS case–control study of estrogen metabolism and ovarian and endometrial cancer were studied of whom 609 were current E + P users (351 used CEE + MPA), while 272 used E alone (162 used CEE). Fifteen EM were measured, and analyses were conducted for each metabolite, hydroxylation pathway (2-, 4-, or 16-pathway) and ratios of pathway concentrations using inverse probability weighted linear regression. Compared to E + P users, all EM were higher in E alone users (significant for unconjugated estrone, total/conjugated estradiol, total/unconjugated 2-methoxyestrone, 4-methoxyestrone and unconjugated estriol). The relative concentrations of 2- and 4-pathway EM did not differ between the MHT users (2-pathway EM comprised 15% and 4-pathway EM <2% of the total), but 16-pathway EM were lower in E alone users (p = 0.036). Ratios of 2- and 4-pathway EM compared to 16-pathway EM were significantly higher in E alone compared to E + P users. Similar but not significant patterns were observed in CEE-alone and CEE + MPA users. Our data suggest that compared to E + P users, women using E alone have more extensive metabolism via the 2- vs. the competing 16-pathway. This is consistent with epidemiologic evidence of reduced postmenopausal breast cancer risk associated with this metabolic profile and may provide a clue to the breast cancer risk reduction in CEE alone users during the WHI. 相似文献
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Bonifaci N Palafox M Pellegrini P Osorio A Benítez J Peterlongo P Manoukian S Peissel B Zaffaroni D Roversi G Barile M Viel A Mariette F Bernard L Radice P Kaufman B Laitman Y Milgrom R Friedman E Sáez ME Climent F Soler MT Diez O Balmaña J Lasa A Ramón y Cajal T Miramar MD de la Hoya M Pérez-Segura P Caldés T Moreno V Urruticoechea A Brunet J Lázaro C Blanco I Pujana MA González-Suárez E 《Breast cancer research and treatment》2011,129(3):947-954
Intracellular signaling mediated by the receptor activator of nuclear factor-κB [Rank, encoded by the tumor necrosis factor receptor superfamily, member 11a (Tnfrsf11a) gene] is fundamental for mammary gland development in mice, regulating the expansion of stem and progenitor cell compartments. Conversely, Rank overexpression in mice promotes abnormal proliferation and impairs differentiation, leading to an increased incidence of tumorigenesis. Here, we show that a common genetic variant near the 5'-end of TNFRSF11A, rs7226991, is associated with breast cancer risk in the general population and among carriers of mutations in the breast cancer 2, early onset (BRCA2) gene. Akin to the results of the Cancer and Genetics Markers of Susceptibility initiative, combined analysis of rs7226991 in two Spanish case-control studies (1,365 controls and 1,323 cases in total) revealed a significant association with risk: odds ratio (OR) = 0.88, 95% confidence interval (CI) 0.78-0.98, P (trend) = 0.025. Subsequent examination of BRCA1 (n = 1,017) and BRCA2 (n = 885) mutation carriers revealed a consistent association in the latter group: weighted hazard ratio ((w)HR) = 0.70; 95% CI 0.55-0.88; and P (trend) = 0.003; compared to BRCA1 mutation carriers, (w)HR = 0.91; 95% CI 0.76-1.10; and P (trend) = 0.33. The results of this study need to be replicated in other populations and with larger numbers of BRCA1/2 mutation carriers. 相似文献
95.
Ori Shen MD Simcha Yagel MD Dan V. Valsky MD Roni Rabinowitz MD Yaron Zalel MD 《Journal of ultrasound in medicine》2011,30(6):827-831
Prenatal imaging of the fetal cerebellar vermis is challenging even for experienced examiners. We found that by aiming the ultrasound beam through the mastoid fontanel and then rotating the data set in a multiplanar reconstruction and applying volume contrast imaging in the C plane, we were consistently able to obtain images of the vermis in the standard midsagittal plane. Images of the fetal vermis suitable for morphologic evaluation were obtained in 408 of 414 cases (98.5%) at gestational ages of 18 weeks to 31 weeks 6 days; the examination time was only minimally increased. 相似文献
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Background and aims
Occult hepatitis B virus infection (OBI) poses a challenge to the safety of blood donation. The prevalence of OBI is not well documented in Indonesia, although this information in such an endemic country is needed. This study was aimed to evaluate the prevalence of occult hepatitis B in blood donors from two cities of Indonesia, and to study the genetic variation and its effect on the predicted antigenicity of HBsAg. 相似文献99.
Sheiner E Peleg R Levy A 《European journal of obstetrics, gynecology, and reproductive biology》2006,129(1):41-45
OBJECTIVE: Celiac disease is a permanent intolerance to gluten, probably induced by an autoimmune mechanism. Controversy exists regarding the association between celiac disease and infertility, abortions, intra-uterine growth restriction (IUGR) and stillbirths. The present study was designed to investigate pregnancy outcome of patients with celiac disease. METHODS: A retrospective comparison between all pregnancies of women with and without known celiac disease, delivered during the years 1988-2002, was conducted. RESULTS: During the study period there were 48 deliveries of patients with celiac disease and 143,663 pregnancies of patients without known celiac disease. No statistically significant differences were noted between the groups regarding maternal or perinatal outcomes, including fertility treatments (0% among patients with known celiac versus 2.5% among patients without known celiac sprue; p=0.267), recurrent abortions (0 versus 5.2%; p=0.103), perinatal mortality (2.1 versus 1.4%; p=0.668). However, higher rates of labor induction (29.2 versus 11.9%; p<0.001) and IUGR (6.3 versus 2.1%; p=0.042) were found among patients with celiac disease as compared to patients without known celiac disease. CONCLUSION: The course of pregnancy of patients with celiac disease including perinatal outcomes is favorable. Since we found higher rates of IUGR, careful surveillance should be performed for early detection of IUGR. Further, prospective studies should focus on screening for celiac disease among patients presenting with IUGR of an unknown etiology. 相似文献
100.
Falk RT Gentzschein E Stanczyk FZ Garcia-Closas M Figueroa JD Ioffe OB Lissowska J Brinton LA Sherman ME 《Breast cancer research and treatment》2012,131(1):287-294
Elevated levels of circulating estrogens and androgens are linked to higher breast cancer risk among postmenopausal women;
however, little is known about hormone levels within the breast. Hormone concentrations within the breast may not be reflected
in the blood and are likely important contributors to breast carcinogenesis. We used a previously validated method to measure
levels of estrone, estradiol, androstenedione, and testosterone in adipose tissue removed as part of breast excisions performed
for cancer in 100 postmenopausal women (69 ER/PR +/+ and 31 ER/PR −/−) participating in a breast cancer case–control study.
We also measured the same steroid hormones, as well as estrone sulfate, and sex hormone-binding globulin (SHBG) in serum from
these patients and 100 controls matched on ages at blood collection and on menopause. Overall, concentrations of serum hormones
did not vary significantly between controls and cases. However, women with ER−/PR− breast cancers had lower circulating levels
of all measured sex steroid hormones and higher SHBG levels than women with ER+/PR+ breast cancers and controls. Similarly,
hormone concentrations in breast adipose tissue were higher among women with ER+/PR+ compared to ER−/PR− breast cancer, although
differences were only significant for testosterone. These data demonstrate that high sex steroid concentrations in both serum
and adipose tissues are more strongly related to ER+/PR+ than ER−/PR− breast cancers. Measurement of sex hormones in serum
and in the microenvironment may help in understanding the hormonal etiology of breast cancer, suggest methods for prevention,
and have value in gauging treatment response and prognosis. 相似文献